Sengoloa sena ke karolo ea sehlooho sa lipatlisiso "Mahlale a tsoetseng pele a bioremediation le mekhoa ea ho sebelisa hape metsoako ea tlhaho ea maiketsetso (SOC). Sheba lingoloa tsohle tse 14
Li-hydrocarbon tse nang le aromatic hydrocarbons tse nang le boima bo tlase ba limolek'hule (li-PAH) tse kang naphthalene le naphthalene tse nkeloang sebaka (methylnaphthalene, naphthoic acid, 1-naphthyl-N-methylcarbamate, jj.) li sebelisoa haholo liindastering tse fapaneng 'me li na le chefo ea geno, li fetoha le ho baka kankere linthong tse phelang. Metsoako ena ea tlhaho ea maiketsetso (li-SOC) kapa li-xenobiotics li nkoa e le litšila tse tlang pele 'me li beha kotsing e kholo tikolohong ea lefats'e le bophelong ba sechaba. Matla a mesebetsi ea batho (mohlala, khase ea mashala, ho hloekisa oli, mosi o tsoang likoloing le lits'ebetso tsa temo) a khetholla mahloriso, qetello le lipalangoang tsa metsoako ena e fumanehang hohle le e sa feleng. Ntle le mekhoa ea phekolo/ho tlosa 'mele le ea lik'hemik'hale, mahlale a tala le a tikoloho a kang bioremediation, a sebelisang likokoana-hloko tse khonang ho senya li-POC ka ho feletseng kapa ho li fetola lihlahisoa tse seng chefo, a hlahile e le mokhoa o mong o sireletsehileng, o theko e tlaase le o tšepisang. Mefuta e fapaneng ea baktheria e leng ea phyla Proteobacteria (Pseudomonas, Pseudomonas, Comamonas, Burkholderia, le Neosphingobacterium), Firmicutes (Bacillus le Paenibacillus), le Actinobacteria (Rhodococcus le Arthrobacter) mobung oa microbiota li bontšitse bokhoni ba ho senya metsoako e fapaneng ea lintho tse phelang. Lithuto tsa metabolism, genomics, le tlhahlobo ea metagenomic li re thusa ho utloisisa ho rarahana ha catabolic le mefuta-futa e teng mefuteng ena e bonolo ea bophelo, e ka sebelisoang hape bakeng sa biodegradation e sebetsang hantle. Boteng ba nako e telele ba li-PAH bo bakile ho hlaha ha li-phenotypes tse ncha tsa ho senyeha ka phetiso ea liphatsa tsa lefutso tse otlolohileng ho sebelisoa likarolo tsa liphatsa tsa lefutso tse kang plasmids, transposons, bacteriophages, lihlekehleke tsa genomic, le likarolo tse kopaneng tse kopaneng. Baeloji ea litsamaiso le boenjiniere ba liphatsa tsa lefutso ba libaka tse ikhethileng kapa metse ea mohlala (consortia) li ka nolofalletsa bioremediation e felletseng, e potlakileng le e sebetsang ea li-PAH tsena ka litlamorao tsa tšebelisano. Tlhahlobong ena, re shebana le litsela tse fapaneng tsa metabolism le mefuta-futa, sebopeho le mefuta-futa ea liphatsa tsa lefutso, le likarabo/liphetoho tsa sele tsa naphthalene le libaktheria tse senyang naphthalene tse nkeloang sebaka. Sena se tla fana ka tlhahisoleseling ea tikoloho bakeng sa ts'ebeliso ea tšimo le ntlafatso ea khatello bakeng sa phekolo e sebetsang hantle ea bioremediation.
Nts'etsopele e potlakileng ea liindasteri (lik'hemik'hale tsa petrochemical, temo, meriana, lidae tsa masela, litlolo, jj.) e kentse letsoho katlehong ea moruo oa lefats'e le ho ntlafatsa maemo a bophelo. Nts'etsopele ena e kholo e bakile tlhahiso ea palo e kholo ea metsoako ea tlhaho ea maiketsetso (li-SOC), e sebelisoang ho etsa lihlahisoa tse fapaneng. Metsoako ena ea kantle ho naha kapa li-SOC e kenyelletsa li-hydrocarbon tse nkhang hamonate tsa polycyclic (li-PAH), chefo e bolaeang likokoanyana, li-herbicide, li-plasticizer, lidae, meriana, li-organophosphate, li-lake retardants, li-solvents tse feto-fetohang tsa tlhaho, jj. Li ntšoa sepakapakeng, libakeng tsa metsing le tsa lefats'e moo li nang le litlamorao tse ngata, tse bakang litlamorao tse mpe ho li-bioform tse fapaneng ka ho fetola thepa ea fisik'hemik'hale le sebopeho sa sechaba (Petrie et al., 2015; Bernhardt et al., 2017; Sarkar et al., 2020). Ditshila tse ngata tse nkhang hamonate di na le ditlamorao tse matla le tse senyang hodima dibaka tse ngata tse sa senyehang tsa tikoloho/dibaka tse nang le mefutafuta ya diphedi (mohlala, mafika a dikorale, maqhoa a Arctic/Antarctic, matsha a dithaba tse telele, dithaba tse tebileng, jj.) (Jones 2010; Beyer et al. 2020; Nordborg et al. 2020). Diphuputso tsa moraorao tsa geomicrobiological di bontshitse hore ho bewa ha dintho tse entsweng ka tlhaho (mohlala, ditshila tse nkhang hamonate) le dintho tse tswang ho tsona hodima meaho ya maiketsetso (tikoloho e hahiloeng) (mohlala, dibaka tsa lefa la setso le diemahale tse entsweng ka granite, lejwe, lehong le tshepe) ho potlakisa ho senyeha ha tsona (Gadd 2017; Liu et al. 2018). Mesebetsi ya batho e ka matlafatsa le ho mpefatsa ho senyeha ha diemahale le meaho ka tshilafatso ya moya le phetoho ya tlelaemete (Liu et al. 2020). Ditshila tsena tsa tlhaho di arabela mouwane wa metsi sepakapakeng mme tsa dula hodima moaho, di baka ho senyeha ha mmele le dikhemikhale tsa thepa. Ho bola ha diphedi ho tsebahala haholo e le diphetoho tse sa batleheng ponahalong le thepa ya dintho tse bakwang ke dintho tse phelang tse amang poloko ya tsona (Pochon le Jaton, 1967). Ketso e eketsehileng ya dikokwana-hloko (metabolism) ya dikokwana-hloko tsena e ka fokotsa botsitso ba sebopeho, katleho ya paballo le boleng ba setso (Gadd, 2017; Liu et al., 2018). Ka lehlakoreng le leng, maemong a mang, ho ikamahanya le dikokwana-hloko le karabelo ya tsona meahong ena ho fumanwe ho le molemo ha di bopa di-biofilm le makgapetla a mang a sireletsang a fokotsang sekgahla sa ho bola/ho bola (Martino, 2016). Ka hona, ntshetsopele ya maano a sebetsang a paballo e tsitsitseng ya nako e telele bakeng sa diemahale tsa majwe, tshepe le lehong e hloka kutlwisiso e tebileng ya ditshebetso tsa bohlokwa tse amehang tshebetsong ena. Ha ho bapiswa le ditshebetso tsa tlhaho (tshebetso ya jeoloji, mello ya meru, ho phatloha ha seretse se chesang, dikarabelo tsa dimela le dibaktheria), mesebetsi ya batho e fella ka ho lokollwa ha bongata bo boholo ba di-hydrocarbon tse nkhang hamonate tsa polycyclic (PAHs) le khabone e nngwe ya organic (OC) dibakeng tsa tikoloho. Li-PAH tse ngata tse sebelisoang temong (likokonyana tse bolaeang likokoanyana le chefo e bolaeang likokoanyana tse kang DDT, atrazine, carbaryl, pentachlorophenol, jj.), indasteri (oli e tala, seretse/litšila tsa oli, polasetiki e entsoeng ka peterole, li-PCB, li-plasticizer, sesepa, li-disinfectant, fumigants, monko o monate le li-preservative), lihlahisoa tsa tlhokomelo ea botho (li-sunscreen, li-disinfectant, li-repellent likokoanyana le li-musk tsa polycyclic) le lithunya (liqhomane tse kang 2,4,6-TNT) ke li-xenobiotic tse ka bang teng tse ka amang bophelo bo botle ba polanete (Srogi, 2007; Vamsee-Krishna le Phale, 2008; Petrie et al., 2015). Lethathamo lena le ka atolosoa ho kenyelletsa metsoako e entsoeng ka peterole (oli ea mafura, li-lubricant, asphaltenes), bioplastics e boima bo phahameng ba limolek'hule, le li-ionic liquids (Amde et al., 2015). Tafole ea 1 e thathamisa litšila tse fapaneng tse nkhang hamonate le ts'ebeliso ea tsona liindastering tse fapaneng. Lilemong tsa morao tjena, mesi e tsoang ho batho ea metsoako ea lintho tse phelang e feto-fetohang, hammoho le carbon dioxide le likhase tse ling tse futhumatsang lefatše, e qalile ho eketseha (Dvorak et al., 2017). Leha ho le joalo, litlamorao tsa batho li feta tsa tlhaho haholo. Ho phaella moo, re fumane hore li-SOC tse 'maloa li ntse li tsoela pele libakeng tse ngata tsa tikoloho' me li khethollotsoe e le litšila tse hlahang tse nang le litlamorao tse mpe ho li-biome (Setšoantšo sa 1). Mekhatlo ea tikoloho e kang United States Environmental Protection Agency (USEPA) e kenyelelitse tse ngata tsa litšila tsena lenaneng la tsona la lintho tse tlang pele ka lebaka la thepa ea tsona ea cytotoxic, genotoxic, mutagenic, le carcinogenic. Ka hona, melaoana e thata ea ho lahla le maano a sebetsang a ho phekola/ho tlosa litšila tikolohong e silafetseng ea hlokahala. Mekhoa e fapaneng ea kalafo ea 'mele le ea lik'hemik'hale joalo ka pyrolysis, kalafo ea oxidative thermal, moea o kenang, ho tlatsa lithōle, ho chesa, jj. ha e sebetse ebile e bitsa chelete e ngata 'me e hlahisa lihlahisoa tse senyang, tse chefo le tse thata ho li phekola. Ka temoso e ntseng e eketseha ea tikoloho lefatšeng ka bophara, likokoana-hloko tse khonang ho senya litšila tsena le lintho tse tsoang ho tsona (tse kang halogenated, nitro, alkyl le/kapa methyl) li hohela tlhokomelo e ntseng e eketseha (Fennell et al., 2004; Haritash le Kaushik, 2009; Phale et al., 2020; Sarkar et al., 2020; Schwanemann et al., 2020). Tšebeliso ea likokoana-hloko tsena tsa tlhaho tse khethiloeng feela kapa litsong tse tsoakiloeng (likolone) bakeng sa ho tlosa litšila tse nkhang hamonate e na le melemo mabapi le polokeho ea tikoloho, litšenyehelo, katleho, katleho le botsitso. Bafuputsi ba boetse ba hlahloba kopanyo ea lits'ebetso tsa likokoana-hloko le mekhoa ea redox ea electrochemical, e leng litsamaiso tsa bioelectrochemical (BES), e le theknoloji e tšepisang bakeng sa kalafo/ho tlosa litšila (Huang et al., 2011). Theknoloji ea BES e hohetse tlhokomelo e ntseng e eketseha ka lebaka la bokhoni ba eona bo phahameng, litšenyehelo tse tlase, polokeho ea tikoloho, ts'ebetso ea mocheso oa kamore, lisebelisoa tse lumellanang le lintho tse phelang, le bokhoni ba ho khutlisa lihlahisoa tsa bohlokoa (mohlala, motlakase, mafura le lik'hemik'hale) (Pant et al., 2012; Nazari et al., 2020). Ho fihla ha tatellano ea liphatsa tsa lefutso tse nang le throughput e phahameng le lisebelisoa/mekhoa ea omics ho fane ka leseli le lengata le lecha mabapi le taolo ea liphatsa tsa lefutso, proteomics, le fluxomics ea liketso tsa likokoana-hloko tse fapaneng tse senyehang. Ho kopanya lisebelisoa tsena le baeloji ea litsamaiso ho ntlafalitse kutloisiso ea rona ea khetho le ho lokisa litsela tse reriloeng tsa catabolic ka har'a likokoana-hloko (ke hore, moralo oa metabolism) ho fihlela biodegradation e sebetsang hantle le e sebetsang. Ho rala maano a sebetsang a bioremediation ho sebelisa likokoana-hloko tse loketseng tse khethiloeng, re hloka ho utloisisa bokhoni ba biochemical, mefuta-futa ea metabolism, sebopeho sa liphatsa tsa lefutso, le tikoloho (autoecology/synecology) ea likokoana-hloko.
Setšoantšo sa 1. Mehloli le litsela tsa li-PAH tse nang le limolek'hule tse tlase ho pholletsa le libaka tse fapaneng tsa tikoloho le lintlha tse fapaneng tse amang biota. Mela e ferekantsoeng e emela likamano lipakeng tsa likarolo tsa tikoloho.
Tlhahlobong ena, re lekile ho akaretsa lintlha tse mabapi le ho senyeha ha li-PAH tse bonolo tse kang naphthalene le naphthalene tse nkeloang sebaka ke li-isolate tse fapaneng tsa baktheria tse akaretsang litsela tsa metabolism le mefuta-futa, li-enzyme tse amehang ho senyeheng, sebopeho/likarolo tsa liphatsa tsa lefutso le mefuta-futa, likarabo tsa sele le likarolo tse fapaneng tsa ho lokisoa ha liphatsa tsa lefutso. Ho utloisisa maemo a biochemical le a limolek'hule ho tla thusa ho khetholla mefuta e loketseng ea moamoheli le boenjiniere ba tsona bo eketsehileng ba liphatsa tsa lefutso bakeng sa ho lokisoa ha likokoana-hloko tse joalo tsa bohlokoa. Sena se tla thusa ho nts'etsapele maano a ho theha sehlopha sa libaktheria tse ikhethileng sebakeng seo bakeng sa ho lokisoa ha likokoana-hloko ka katleho.
Boteng ba palo e kholo ea metsoako e chefo le e kotsi ea monko o monate (e khotsofatsang molao oa Huckel 4n + 2π lielektrone, n = 1, 2, 3, …) e baka tšokelo e kholo mecheng e fapaneng ea tikoloho joalo ka moea, mobu, sediment, le bokaholimo le metsi a ka tlas'a lefatše (Puglisi et al., 2007). Metsoako ena e na le masale a benzene a le mong (monocyclic) kapa masale a benzene a mangata (polycyclic) a hlophisitsoeng ka mokhoa o otlolohileng, o kobehileng kapa oa sehlopha 'me a bontša botsitso (botsitso/ho se tsitse) tikolohong ka lebaka la matla a phahameng a resonance a negative le ho se tsitse (ho se tsitse), e leng se ka hlalosoang ke ho se tsitse ha bona ka metsi le boemo bo fokotsehileng. Ha lesale la monko o monate le nkeloa sebaka ke lihlopha tsa methyl (-CH3), carboxyl (-COOH), hydroxyl (-OH), kapa sulfonate (-HSO3), le tsitsitse haholoanyane, le na le kamano e matla le limolek'hule tse kholo, 'me le bokellana ka har'a litsamaiso tsa baeloji (Seo et al., 2009; Phale et al., 2020). Li-hydrocarbon tse ling tse nang le boima bo tlase ba limolek'hule tse nang le polycyclic aromatic (LMWAHs), tse kang naphthalene le lintho tse tsoang ho eona [methylnaphthalene, naphthoic acid, naphthalenesulfonate, le 1-naphthyl N-methylcarbamate (carbaryl)], li kenyelelitsoe lethathamong la lintho tse silafatsang tsa tlhaho tse ka sehloohong ke US Environmental Protection Agency e le tse chefo ea genotoxic, mutagenic, le/kapa tse bakang kankere (Cerniglia, 1984). Ho lokollwa ha sehlopha sena sa di-NM-PAH tikolohong ho ka fella ka ho bokellana ha metsoako ena maemong ohle a ketane ya dijo, ka hona ho ama bophelo bo botle ba ditikoloho (Binkova et al., 2000; Srogi, 2007; Quinn et al., 2009).
Mehloli le litsela tsa li-PAH ho ea ho biota ke haholo-holo ka ho falla le likamano pakeng tsa likarolo tse fapaneng tsa tikoloho joalo ka mobu, metsi a ka tlas'a lefatše, metsi a holim'a lefatše, lijalo le sepakapaka (Arey le Atkinson, 2003). Setšoantšo sa 1 se bontša likamano le kabo ea li-PAH tse fapaneng tse boima bo tlase ba limolek'hule tikolohong ea tikoloho le litsela tsa tsona tsa ho pepesehela biota/batho. Li-PAH li behoa holim'a libaka ka lebaka la tšilafalo ea moea le ka ho falla (ho kheloha) ha mesi e tsoang likoloing, likhase tsa mosi oa indasteri (khase ea mashala, ho tuka le tlhahiso ea coke) le ho li beha. Mesebetsi ea indasteri e kang ho etsa masela a maiketsetso, lidae le lipente; paballo ea patsi; ts'ebetso ea rabara; mesebetsi ea tlhahiso ea samente; tlhahiso ea chefo e bolaeang likokoanyana; le lits'ebetso tsa temo ke mehloli e meholo ea li-PAH lits'ebetsong tsa lefatše le tsa metsing (Bamforth le Singleton, 2005; Wick et al., 2011). Lithuto li bontšitse hore mobu o libakeng tsa litoropo le tsa litoropo, haufi le litsela tse kholo, le metseng e meholo o kotsing e kholo ea li-hydrocarbon tse nkhang hamonate tsa polycyclic (PAHs) ka lebaka la mesi e tsoang lifemeng tsa motlakase, ho futhumatsa matlo, meroalo ea sephethephethe sa moea le litsela, le mesebetsi ea kaho (Suman et al., 2016). (2008) e bontšitse hore li-PAH tse mobung o haufi le litsela New Orleans, Louisiana, USA li ne li le holimo ho 7189 μg/kg, athe sebakeng se bulehileng, li ne li le 2404 μg/kg feela. Ka ho tšoanang, maemo a PAH a holimo ho 300 μg/kg a tlalehiloe libakeng tse haufi le libaka tsa khase ea mashala metseng e 'maloa ea US (Kanaly le Harayama, 2000; Bamforth le Singleton, 2005). Mobu o tswang metseng e fapaneng ya India jwalo ka Delhi (Sharma et al., 2008), Agra (Dubey et al., 2014), Mumbai (Kulkarni le Venkataraman, 2000) le Visakhapatnam (Kulkarni et al., 2014) o tlalehilwe hore o na le maemo a hodimo a di-PAH. Metswako e monko o monate e monyela habonolo hodima dikarolwana tsa mobu, dintho tse phelang le diminerale tsa letsopa, ka hona e ba dikotsi tse kgolo tsa khabone dibakeng tsa tikoloho (Srogi, 2007; Peng et al., 2008). Mehlodi e meholo ya di-PAH dibakeng tsa tikoloho tsa metsing ke pula (pula e metsi/e omileng le mouwane wa metsi), metsi a tswang ditoropong, metsi a ditshila, ho tjhaja metsi a ka tlasa lefatshe jj. (Srogi, 2007). Ho hakanngwa hore hoo e ka bang 80% ya di-PAH dibakeng tsa tikoloho tsa lewatle di tswa ho pula, ho tjhesehela mobu, le ho tsholoha ha matlakala (Motelay-Massei et al., 2006; Srogi, 2007). Maemo a hodimo a di-PAH metsing a ka hodima metsi kapa leachate e tswang dibakeng tsa ho lahla matlakala a tiileng a qetella a dutla ka metsing a ka tlase ho lefatshe, e leng se bakang kotsi e kgolo bophelong ba setjhaba kaha baahi ba fetang 70% ba Asia Borwa le Borwa-Botjhabela ba nwa metsi a ka tlase ho lefatshe (Duttagupta et al., 2019). Phuputso ya morao tjena ya Duttagupta et al. (2020) ya ditlhahlobo tsa noka (32) le metsi a ka tlase ho lefatshe (235) tse tswang West Bengal, India, e fumane hore ho hakanngwa hore 53% ya baahi ba ditoropong le 44% ya baahi ba mahaeng (kakaretso ya baahi ba dimilione tse 20) ba ka pepesehela naphthalene (4.9–10.6 μg/L) le dihlahiswa tsa yona. Mekgwa e fapaneng ya tshebediso ya mobu le keketseho ya ho ntshwa ha metsi a ka tlase ho lefatshe di nkwa e le mabaka a ka sehloohong a laolang ho tsamaiswa ha di-PAH tse boima bo tlase ba dimolek'hule ka tlase ho lefatshe. Ho tsholoha ha metsi a ditshila a temo, a masepala le a diindasteri, le ho tsholoha ha matlakala/ditshireletso ho fumanwe ho angwa ke di-PAH diboteng tsa dinoka le ditshila tse ka tlase ho lefatshe. Pula ea sepakapaka e mpefatsa tšilafalo ea PAH le ho feta. Maemo a phahameng a li-PAH le li-alkyl derivatives tsa tsona (ka kakaretso tse 51) a tlalehiloe linōkeng/libakeng tsa metsi lefatšeng ka bophara, joalo ka Noka ea Fraser, Noka ea Louan, Noka ea Denso, Noka ea Missouri, Noka ea Anacostia, Noka ea Ebro, le Noka ea Delaware (Yunker et al., 2002; Motelay-Massei et al., 2006; Li et al., 2010; Amoako et al., 2011; Kim et al., 2018). Libakeng tsa Noka ea Ganges, naphthalene le phenanthrene li fumanoe e le tsa bohlokoa ka ho fetisisa (li fumanoe ho 70% ea lisampole) (Duttagupta et al., 2019). Ho feta moo, lithuto li bontšitse hore chlorine ea metsi a nooang e ka lebisa ho thehoeng ha li-PAH tse chefo tse nang le oksijene le chlorine (Manoli le Samara, 1999). Li-PAH li bokellana ka har'a lijo-thollo, litholoana le meroho ka lebaka la ho monngoa ke limela mobung o silafetseng, metsing a ka tlas'a lefatše le pula (Fismes et al., 2002). Libōpuoa tse ngata tsa metsing tse kang litlhapi, li-mussels, li-clam le li-shrimp li silafalitsoe ke li-PAH ka lebaka la ho ja lijo tse silafetseng le metsi a leoatle, hammoho le ka lisele le letlalo (Mackay le Fraser, 2000). Mekhoa ea ho pheha/ho sebetsana le lijo tse kang ho halika, ho besa, ho tsuba, ho hadika, ho omisa, ho baka le ho pheha ka mashala le tsona li ka lebisa ho bongata ba li-PAH lijong. Sena se itšetlehile haholo ka khetho ea thepa ea ho tsuba, tekanyo ea phenolic/aromatic hydrocarbon, mokhoa oa ho pheha, mofuta oa hitara, tekanyo ea mongobo, phepelo ea oksijene le mocheso oa ho chesa (Guillén et al., 2000; Gomes et al., 2013). Li-polycyclic aromatic hydrocarbons (li-PAH) le tsona li fumanoe ka lebese ka maemo a fapaneng (0.75–2.1 mg/L) (Girelli et al., 2014). Ho bokellana ha li-PAH tsena lijong ho boetse ho itšetlehile ka thepa ea fisik'hemik'hale ea lijo, ha litlamorao tsa tsona tse chefo li amana le mesebetsi ea 'mele, ts'ebetso ea metabolism, ho monya, kabo le kabo ea 'mele (Mechini et al., 2011).
Chefo le litlamorao tse kotsi tsa li-hydrocarbon tse nkhang hamonate tsa polycyclic (li-PAH) li 'nile tsa tsejoa ka nako e telele (Cherniglia, 1984). Li-hydrocarbon tse nkhang hamonate tsa polycyclic tse boima bo tlase ba limolek'hule (li-LMW-PAH) (masale a mabeli ho isa ho a mararo) li ka tlama ka kopanelo ho limolek'hule tse fapaneng tse kang DNA, RNA le liprotheine 'me li baka kankere (Santarelli et al., 2008). Ka lebaka la tlhaho ea tsona ea ho se tšabe metsi, li aroloa ke li-membrane tsa lipid. Ho batho, li-monooxygenase tsa cytochrome P450 li kopanya li-PAH le li-epoxide, tseo tse ling tsa tsona li arabelang haholo (mohlala, baediol epoxide) 'me li ka lebisa phetohong ea lisele tse tloaelehileng hore e be tse kotsi (Marston et al., 2001). Ho phaella moo, lihlahisoa tsa phetoho ea li-PAH tse kang li-quinone, li-phenols, li-epoxide, li-diols, jj. li chefo ho feta metsoako ea motsoali. Li-PAH tse ling le metsoako ea tsona ea metabolism li ka ama lihormone le li-enzyme tse fapaneng metabolism, ka hona li ama kholo hampe, tsamaiso ea methapo e bohareng, tsamaiso ea ho ikatisa le ea ho itšireletsa mafung (Swetha le Phale, 2005; Vamsee-Krishna et al., 2006; Oostingh et al., 2008). Ho pepesehela li-PAH tsa boima bo tlase ba limolek'hule nako e khuts'oane ho tlalehiloe hore li baka ts'ebetso e mpe ea matšoafo le thrombosis ho batho ba nang le asthma le ho eketsa kotsi ea mofetše oa letlalo, matšoafo, senya le mala (Olsson et al., 2010; Diggs et al., 2011). Lithuto tsa liphoofolo li boetse li bontšitse hore ho pepesehela PAH ho ka ba le litlamorao tse mpe ts'ebetsong ea ho ikatisa le nts'etsopele 'me ho ka baka cataract, tšenyo ea liphio le sebete, le jaundice. Lihlahisoa tse fapaneng tsa PAH biotransformation tse kang diols, epoxides, quinones le free radicals (cations) li bontšitsoe li etsa li-adducts tsa DNA. Ho bontšitsoe hore li-adduct tse tsitsitseng li fetola mechine ea ho ikatisa ha DNA, athe li-adduct tse sa tsitsang li ka ntša DNA (haholo-holo ho adenine 'me ka linako tse ling ho ea ho guanine); ka bobeli li ka hlahisa liphoso tse lebisang liphetohong tsa lefutso (Schweigert et al. 2001). Ho phaella moo, li-quinone (benzo-/pan-) li ka hlahisa mefuta ea oksijene e arabelang (ROS), e bakang tšenyo e bolaeang ho DNA le limolek'hule tse ling, ka hona li ama ts'ebetso/bophelo ba lisele (Ewa le Danuta 2017). Ho pepesehela nako e telele ho maemo a tlase a pyrene, biphenyl le naphthalene ho tlalehiloe hore ho baka mofetše liphoofolong tsa liteko (Diggs et al. 2012). Ka lebaka la chefo ea tsona e bolaeang, ho hloekisa/ho tlosa li-PAH tsena libakeng tse amehileng/tse silafetseng ke ntho ea bohlokoa.
Mekhoa e fapaneng ea 'mele le ea lik'hemik'hale e sebelisitsoe ho tlosa li-PAH libakeng/tikolohong tse silafetseng. Mekhoa e kang ho chesa, ho tlosa chlorination, ho oxidation ea UV, ho lokisa le ho ntša solvent e na le mathata a mangata, ho kenyeletsoa ho thehoa ha lihlahisoa tse chefo, ho rarahana ha ts'ebetso, litaba tsa polokeho le taolo, katleho e tlase, le litšenyehelo tse phahameng. Leha ho le joalo, biodegradation ea likokoana-hloko (e bitsoang bioremediation) ke mokhoa o mong o tšepisang o kenyelletsang tšebeliso ea likokoana-hloko ka mokhoa oa litso tse hloekileng kapa likolone. Ha ho bapisoa le mekhoa ea 'mele le ea lik'hemik'hale, ts'ebetso ena e mosa tikolohong, ha e hlasele, e theko e tlaase, 'me e tšoarella. Bioremediation e ka etsoa sebakeng se amehileng (in situ) kapa sebakeng se lokiselitsoeng ka ho khetheha (ex situ) 'me ka hona e nkoa e le mokhoa o tsitsitseng oa tokiso ho feta mekhoa ea setso ea 'mele le ea lik'hemik'hale (Juhasz le Naidu, 2000; Andreoni le Gianfreda, 2007; Megharaj et al., 2011; Phale et al., 2020; Sarkar et al., 2020).
Ho utloisisa mehato ea metabolism ea likokoana-hloko e amehang ho senyeheng ha litšila tse nkhang hamonate ho na le litlamorao tse kholo tsa saense le moruo bakeng sa botsitso ba tikoloho le tikoloho. Khakanyo ea 2.1 × 1018 digrama tsa khabone (C) e bolokoa ka har'a sediment le metsoako ea tlhaho (ke hore, oli, khase ea tlhaho, le mashala, ke hore, mafura a mesaletsa) lefatšeng ka bophara, e leng se etsang monehelo o moholo potolohong ea khabone ea lefats'e. Leha ho le joalo, indasteri e potlakileng, ho ntšoa ha mafura a mesaletsa, le mesebetsi ea batho li felisa matamo ana a khabone a lithospheric, li lokolla khabone ea tlhaho ea 5.5 × 1015 g (e le litšila) sepakapakeng selemo le selemo (Gonzalez-Gaya et al., 2019). Bongata ba khabone ena ea tlhaho bo kena tikolohong ea lefats'e le ea leoatle ka ho sedimenta, ho tsamaisoa le ho phalla ha metsi. Ho phaella moo, litšila tse ncha tse entsoeng ka maiketsetso tse tsoang mafura a mesaletsa, joalo ka polasetiki, li-plasticizer le li-stabilizer tsa polasetiki (li-phthalates le li-isomer tsa tsona), li silafatsa tikoloho ea leoatle, mobu le ea metsing le biota ea tsona ka botebo, ka hona li mpefatsa likotsi tsa boemo ba leholimo ba lefats'e. Mefuta e fapaneng ea li-microplastic, li-nanoplastic, likotoana tsa polasetiki le lihlahisoa tsa tsona tsa monomer tse chefo tse tsoang polyethylene terephthalate (PET) li bokelletsoe Leoatleng la Pacific pakeng tsa Amerika Leboea le Asia Boroa-bochabela, li etsa "Great Pacific Garbage Patch", e leng se senyang bophelo ba leoatle (Newell et al., 2020). Lithuto tsa mahlale li pakile hore ho ke ke ha khoneha ho tlosa litšila/litšila tse joalo ka mekhoa efe kapa efe ea 'mele kapa ea lik'hemik'hale. Moelelong ona, likokoana-hloko tse thusang haholo ke tse khonang ho fetola litšila ka oxidative ho ba carbon dioxide, matla a lik'hemik'hale le lihlahisoa tse ling tse seng chefo tse qetellang li kena lits'ebetsong tse ling tsa potoloho ea limatlafatsi (H, O, N, S, P, Fe, jj.). Kahoo, ho utloisisa tikoloho ea likokoana-hloko ea mineralization ea tšilafalo e nkhang hamonate le taolo ea eona ea tikoloho ho bohlokoa bakeng sa ho lekola potoloho ea carbon ea likokoana-hloko, tekanyetso ea carbon e hloekileng le likotsi tsa boemo ba leholimo ba nakong e tlang. Ka lebaka la tlhoko e potlakileng ea ho tlosa metsoako e joalo tikolohong, ho hlahile liindasteri tse fapaneng tsa tikoloho tse shebaneng le mahlale a hloekileng. Ka tsela e 'ngoe, ho ananela litšila tsa indasteri/lik'hemik'hale tse bokelletsoeng tikolohong (ke hore mokhoa oa ho sebelisa litšila ho ea leruong) ho nkoa e le e 'ngoe ea litšiea tsa moruo o chitja le lipheo tsa nts'etsopele e tsitsitseng (Close et al., 2012). Ka hona, ho utloisisa likarolo tsa metabolism, enzyme le liphatsa tsa lefutso tsa bakhethoa bana ba ka senyehang ke habohlokoa haholo bakeng sa ho tlosoa le ho lokisoa ha lintho tse silafatsang tse joalo tse nkhang hamonate ka katleho.
Har'a lintho tse ngata tse silafatsang tse nkhang hamonate, re ela hloko ka ho khetheha li-PAH tse nang le boima bo tlase ba limolek'hule tse kang naphthalene le naphthalene tse nkeloang sebaka. Metsoako ena ke likarolo tse kholo tsa mafura a tsoang peteroleng, lidae tsa masela, lihlahisoa tsa bareki, chefo e bolaeang likokoanyana (libolo tsa tšoele le lintho tse lelekang likokoanyana), li-plasticizer le li-tannins 'me ka hona li atile libakeng tse ngata tsa tikoloho (Preuss et al., 2003). Litlaleho tsa morao tjena li totobatsa ho bokellana ha naphthalene metsing a leoatle, mobung o ka tlas'a lefatše le mobung o ka tlas'a lefatše, libaka tsa vadose le libetheng tsa noka, e leng se bontšang ho bokellana ha eona tikolohong (Duttagupta et al., 2019, 2020). Tafole ea 2 e akaretsa thepa ea fisik'hemik'hale, lits'ebetso le litlamorao tsa bophelo bo botle ba naphthalene le lintho tse tsoang ho eona. Ha e bapisoa le li-PAH tse ling tse nang le boima bo phahameng ba limolek'hule, naphthalene le lintho tse tsoang ho eona ha li tšabe metsi haholo, ha li qhibilihe metsing 'me li ajoa haholo libakeng tsa tikoloho, kahoo hangata li sebelisoa e le mehlala ea ho ithuta metabolism, liphatsa tsa lefutso le mefuta-futa ea metabolism ea li-PAH. Palo e kholo ea likokoana-hloko li khona ho fetola naphthalene le metsoako ea eona, 'me tlhahisoleseling e felletseng e fumaneha mabapi le litsela tsa tsona tsa metabolism, lienzyme le likarolo tsa taolo (Mallick et al., 2011; Phale et al., 2019, 2020). Ho phaella moo, naphthalene le metsoako ea eona li khethiloe e le metsoako ea mohlala bakeng sa tlhahlobo ea tšilafalo ea tikoloho ka lebaka la bongata ba tsona le ho fumaneha ha tsona. Setsi sa Tšireletso ea Tikoloho sa US se hakanya hore maemo a tloaelehileng a naphthalene ke 5.19 μg ka mithara ea li-cubic ho tsoa mosing oa sakerete, haholo-holo ho tsoa ho cheso e sa fellang, le 7.8 ho isa ho 46 μg ho tsoa mosing o ka thoko, ha ho pepesehela creosote le naphthalene ho le holimo ka makhetlo a 100 ho isa ho a 10,000 (Preuss et al. 2003). Ka ho khetheha Naphthalene e fumanoe e na le chefo ea phefumoloho le kankere ea mofuta, sebaka le bong. Ho latela lithuto tsa liphoofolo, Setsi sa Machaba sa Lipatlisiso tsa Kankere (IARC) se khethile naphthalene e le "kankere e ka bang teng ho batho" (Sehlopha sa 2B)1. Ho pepesehela naphthalene e nketsoeng sebaka, haholo-holo ka ho hema kapa ho tsamaisoa ka molomo (ka molomo), ho baka kotsi ea lisele tsa matšoafo 'me ho eketsa ho ata ha lihlahala tsa matšoafo ho likhoto le litoeba (Lenaneo la Naha la Toxicology 2). Litlamorao tse matla li kenyelletsa ho nyekeloa ke pelo, ho hlatsa, bohloko ba mpa, letšollo, hlooho e opang, pherekano, ho fufuleloa ho hoholo, feberu, tachycardia, jj. Ka lehlakoreng le leng, carbamate antisecticide carbaryl (1-naphthyl N-methylcarbamate) e tlalehiloe e le chefo ho liphoofolo tse se nang lesapo la mokokotlo metsing, liphoofolo tse phelang metsing, linotši tsa mahe a linotši le batho 'me ho bontšitsoe hore e thibela acetylcholinesterase e bakang ho holofala (Smulders et al., 2003; Bulen le Distel, 2011). Ka hona, ho utloisisa mekhoa ea ho senyeha ha likokoana-hloko, taolo ea liphatsa tsa lefutso, lik'hemik'hale le liketso tsa sele ke habohlokoa bakeng sa ho nts'etsapele maano a ho lokisa likokoana-hloko libakeng tse silafetseng.
Tafole ea 2. Tlhahisoleseling e qaqileng mabapi le thepa ea fisik'hemik'hale, ts'ebeliso, mekhoa ea ho khetholla le mafu a amanang le naphthalene le lintho tse tsoang ho eona.
Libakeng tse silafetseng, litšila tse nkhang hamonate tse sa rateheng le tse nang le lipophilic li ka baka litlamorao tse fapaneng tsa sele holim'a microbiome ea tikoloho (sechaba), joalo ka liphetoho mokelikeling oa lera, ho kenella ha lera, ho ruruha ha lipid bilayer, tšitiso ea phetisetso ea matla (ketane ea lipalangoang tsa elektrone/matla a proton), le ts'ebetso ea liprotheine tse amanang le lera (Sikkema et al., 1995). Ho phaella moo, lintho tse ling tse qhibilihang tse kang li-catechol le li-quinone li hlahisa mefuta ea oksijene e arabelang (ROS) 'me li theha li-adducts tse nang le DNA le liprotheine (Penning et al., 1999). Kahoo, bongata ba metsoako e joalo tikolohong ea tikoloho bo fana ka khatello e khethiloeng ho lichaba tsa likokoana-hloko hore e be li-degrade tse sebetsang hantle maemong a fapaneng a fisioloji, ho kenyeletsoa ho monya/ho tsamaisa, phetoho ea ka hare ho sele, ho monya/ho sebelisa, le ho arola.
Patlisiso ea Ribosomal Database Project-II (RDP-II) e senotse hore mefuta eohle ea libaktheria tse 926 e ne e arotsoe ho tsoa mefuteng ea mecha ea litaba kapa ea ntlafatso e silafalitsoeng ke naphthalene kapa lintho tse tsoang ho eona. Sehlopha sa Proteobacteria se ne se e-na le palo e phahameng ka ho fetisisa ea baemeli (n = 755), se lateloa ke Firmicutes (52), Bacteroidetes (43), Actinobacteria (39), Tenericutes (10), le libaktheria tse sa khetholloang (8) (Setšoantšo sa 2). Baemeli ba γ-Proteobacteria (Pseudomonadales le Xanthomonadales) ba ne ba laola lihlopha tsohle tse mpe tsa Gram tse nang le G+C e phahameng (54%), ha Clostridiales le Bacillales (30%) e ne e le lihlopha tse ntle tsa Gram tse nang le G+C e tlase. Ho tlalehiloe hore li-Pseudomonas (palo e phahameng ka ho fetisisa, mefuta e 338) li khona ho senya naphthalene le metsoako ea eona ea methyl libakeng tse fapaneng tse silafetseng tsa tikoloho (sekontiri sa mashala, peterole, oli e tala, seretse, ho tšoloha ha oli, metsi a litšila, litšila tsa tlhaho le libaka tsa ho lahla lithōle) hammoho le libakeng tse sa senyehang tsa tikoloho (mobu, linoka, marotholi le metsi a ka tlas'a lefatše) (Setšoantšo sa 2). Ho feta moo, lithuto tsa ntlafatso le tlhahlobo ea metagenomic ea libaka tse ling li senotse hore mefuta ea Legionella le Clostridium e sa lengoang e ka ba le bokhoni ba ho senya, e leng se bontšang tlhoko ea ho lema libaktheria tsena ho ithuta litsela tse ncha le mefuta-futa ea metabolism.
Setšoantšo sa 2. Mefuta-futa ea taxonomic le kabo ea tikoloho ea baemeli ba baktheria libakeng tse silafalitsoeng ke naphthalene le lintho tse tsoang ho naphthalene.
Har'a likokoana-hloko tse fapaneng tse senyang hydrocarbon e nkhang hamonate, boholo ba tsona li khona ho senya naphthalene e le mohloli o le mong oa khabone le matla. Tatellano ea liketsahalo tse amehang metabolism ea naphthalene e hlalositsoe bakeng sa Pseudomonas sp. (mefuta: NCIB 9816-4, G7, AK-5, PMD-1 le CSV86), Pseudomonas stutzeri AN10, Pseudomonas fluorescens PC20 le mefuta e meng (ND6 le AS1) (Mahajan et al., 1994; Resnick et al., 1996; Annweiler et al., 2000; Basu et al., 2003; Dennis le Zylstra, 2004; Sota et al., 2006; Metabolism e qalwa ke dioxygenase e nang le dikarolo tse ngata [naphthalene dioxygenase (NDO), e leng lesale le etsang dioxygenase e hydroxylating] e susumetsang oxidation ya e nngwe ya masale a monko o monate a naphthalene ho sebediswa oksijene ya molek'hule jwalo ka karolo e nngwe, e fetolang naphthalene ho ba cis-naphthalenediol (Setshwantsho sa 3). Cis-dihydrodiol e fetolelwa ho 1,2-dihydroxynaphthalene ka dehydrogenase. Dioxygenase e kgaolang lesale, 1,2-dihydroxynaphthalene dioxygenase (12DHNDO), e fetola 1,2-dihydroxynaphthalene ho ba 2-hydroxychromene-2-carboxylic acid. Enzymatic cis-trans isomerization e hlahisa trans-o-hydroxybenzylidenepyruvate, e kgaolwang ke hydratase aldolase ho ba salicylic aldehyde le pyruvate. Organic acid pyruvate e ne e le motsoako wa pele wa C3 o tswang masapong a naphthalene carbon mme o lebiswa tseleng e bohareng ya carbon. Ho phaella moo, salicylaldehyde dehydrogenase e itshetlehileng ka NAD+ e fetola salicylaldehyde ho ba salicylic acid. Metabolism mokgahlelong ona e bitswa "tsela e ka hodimo" ya ho senyeha ha naphthalene. Tsela ena e atile haholo dibaktheriang tse ngata tse senyang naphthalene. Leha ho le jwalo, ho na le mekhelo e mmalwa; mohlala, ho Bacillus hamburgii 2 e phelang mochesong, ho senyeha ha naphthalene ho qalwa ke naphthalene. 2,3-dioxygenase ho theha 2,3-dihydroxynaphthalene (Annweiler et al., 2000).
Setšoantšo sa 3. Litsela tsa naphthalene, methylnaphthalene, naphthoic acid, le ho senyeha ha carbaryl. Linomoro tse selikalikoe li emela lienzyme tse ikarabellang bakeng sa phetoho e latellanang ea naphthalene le lihlahisoa tsa eona hore e be lihlahisoa tse latelang. 1 - naphthalene dioxygenase (NDO); 2, cis-dihydrodiol dehydrogenase; 3, 1,2-dihydroxynaphthalene dioxygenase; 4, 2-hydroxychromene-2-carboxylic acid isomerase; 5, trans-O-hydroxybenzylidenepyruvate hydratase aldolase; 6, salicylaldehyde dehydrogenase; 7, salicylate 1-hydroxylase; 8, catechol 2,3-dioxygenase (C23DO); 9, 2-hydroxymuconate semialdehyde dehydrogenase; 10, 2-oxopent-4-enoate hydratase; 11, 4-hydroxy-2-oxopentanoate aldolase; 12, acetaldehyde dehydrogenase; 13, catechol-1,2-dioxygenase (C12DO); 14, muconate cycloisomerase; 15, muconolactone delta-isomerase; 16, β-ketoadipatenollactone hydrolase; 17, β-ketoadipate succinyl-CoA transferase; 18, β-ketoadipate-CoA thiolase; 19, succinyl-CoA: acetyl-CoA succinyltransferase; 20, salicylate 5-hydroxylase; 21 – gentisate 1,2-dioxygenase (GDO); 22, maleylpyruvate isomerase; 23, fumarylpyruvate hydrolase; 24, methylnaphthalene hydroxylase (NDO); 25, hydroxymethylnaphthalene dehydrogenase; 26, naphthaldehyde dehydrogenase; 27, 3-formylsalicylic acid oxidase; 28, hydroxyisophthalate decarboxylase; 29, carbaryl hydrolase (CH); 30, 1-naphthol-2-hydroxylase.
Ho latela sephedi le sebopeho sa sona sa lefutso, salicylic acid e hlahang e ntse e fetoloa ka tsela ea catechol ho sebelisoa salicylate 1-hydroxylase (S1H) kapa ka tsela ea gentisate ho sebelisoa salicylate 5-hydroxylase (S5H) (Setšoantšo sa 3). Kaha salicylic acid ke eona e bohareng bo boholo ba metabolism ea naphthalene (tsela e ka holimo), mehato e tlohang ho salicylic acid ho ea ho TCA intermediate hangata e bitsoa tsela e ka tlase, 'me liphatsa tsa lefutso li hlophisitsoe hore e be operon e le' ngoe. Ho tloaelehile ho bona hore liphatsa tsa lefutso tse tseleng e ka holimo ea operon (nah) le tsela e ka tlase ea operon (sal) li laoloa ke lintlha tse tloaelehileng tsa taolo; mohlala, NahR le salicylic acid li sebetsa e le li-inducer, tse lumellang li-operon ka bobeli ho fetola naphthalene ka botlalo (Phale et al., 2019, 2020).
Ho phaella moo, catechol e kgaolwa ka potoloho ho 2-hydroxymuconate semialdehyde ka tsela ya meta ke catechol 2,3-dioxygenase (C23DO) (Yen et al., 1988) mme e hydrolyzed hape ke 2-hydroxymuconate semialdehyde hydrolase ho etsa 2-hydroxypent-2,4-dienoic acid. 2-hydroxypent-2,4-dienoate ebe e fetolelwa ho pyruvate le acetaldehyde ke hydratase (2-oxopent-4-enoate hydratase) le aldolase (4-hydroxy-2-oxopentanoate aldolase) ebe e kena tseleng e bohareng ya khabone (Setshwantsho sa 3). Ka tsela e nngwe, catechol e kgaolwa ka potoloho ho cis,cis-muconate ka tsela ya ortho ke catechol 1,2-oxygenase (C12DO). Muconate cycloisomerase, muconolactone isomerase, le β-ketoadipate-nollactone hydrolase li fetola cis, cis-muconate ho 3-oxoadipate, e kenang tseleng e bohareng ea khabone ka succinyl-CoA le acetyl-CoA (Nozaki et al., 1968) (Setšoantšo sa 3).
Tseleng ea gentisate (2,5-dihydroxybenzoate), lesale la monko o monate le petsoha ka gentisate 1,2-dioxygenase (GDO) ho etsa maleylpyruvate. Sehlahisoa sena se ka hasoa ka ho toba ho pyruvate le malate, kapa se ka hasoa ho etsa fumarylpyruvate, e ka hasoang ka hydrolyze ho pyruvate le fumarate (Larkin le Day, 1986). Khetho ea tsela e 'ngoe e bonoe libaktheria tsa Gram-negative le Gram-positive maemong a biochemical le a liphatsa tsa lefutso (Morawski et al., 1997; Whyte et al., 1997). Libaktheria tsa Gram-negative (Pseudomonas) li khetha ho sebelisa salicylic acid, e leng ntho e susumetsang metabolism ea naphthalene, e e tlosa carboxylating ho catechol ho sebelisoa salicylate 1-hydroxylase (Gibson le Subramanian, 1984). Ka lehlakoreng le leng, ho dibaktheria tse nang le Gram-positive (Rhodococcus), salicylate 5-hydroxylase e fetola salicylic acid ho gentisic acid, athe salicylic acid ha e na phello e inductive hodima phetolelo ya dijini tsa naphthalene (Grund et al., 1992) (Setshwantsho sa 3).
Ho tlalehiloe hore mefuta e kang Pseudomonas CSV86, Oceanobacterium NCE312, Marinhomonas naphthotrophicus, Sphingomonas paucimobilis 2322, Vibrio cyclotrophus, Pseudomonas fluorescens LP6a, mefuta ea Pseudomonas le Mycobacterium e ka senya monomethylnaphthalene kapa dimethylnaphthalene (Dean-Raymond le Bartha, 1975; Cane le Williams, 1982; Mahajan et al., 1994; Dutta et al., 1998; Hedlund et al., 1999). Har'a tsona, tsela ea ho senyeha ha 1-methylnaphthalene le 2-methylnaphthalene ea Pseudomonas sp. CSV86 e ithutiloe ka ho hlaka maemong a biochemical le enzyme (Mahajan et al., 1994). 1-Methylnaphthalene e sebelisoa ka litsela tse peli. Taba ea pele, lesale la monko o monate le hydroxylated (lesale le sa nkeloang sebaka la methylnaphthalene) ho etsa cis-1,2-dihydroxy-1,2-dihydro-8-methylnaphthalene, e ntšetsoang oxidized ho methyl salicylate le methylcatechol, ebe e kena tseleng e bohareng ea carbon kamora ho arohana ha lesale (Setšoantšo sa 3). Tsela ena e bitsoa "tsela ea mohloli oa carbon". "Tsela ea bobeli ea ho tlosa chefo", sehlopha sa methyl se ka ntšetsoa hydroxylated ke NDO ho etsa 1-hydroxymethylnaphthalene, e ntšetsoang oxidized ho 1-naphthoic acid 'me ea ntšoa sebakeng sa temo e le sehlahisoa se sa feleng. Lithuto li bontšitse hore mofuta oa CSV86 ha o khone ho hola ho 1- le 2-naphthoic acid e le mohloli o le mong oa carbon le matla, e tiisang tsela ea eona ea ho tlosa chefo (Mahajan et al., 1994; Basu et al., 2003). Ho 2-methylnaphthalene, sehlopha sa methyl se feta hydroxylation ka hydroxylase ho theha 2-hydroxymethylnaphthalene. Ho phaella moo, lesale le sa nkeloang sebaka la lesale la naphthalene le feta hydroxylation ea lesale ho etsa dihydrodiol, e kenngoang oxidized ho 4-hydroxymethylcatechol letotong la liketso tse entsoeng ke enzyme mme e kena tseleng e bohareng ea khabone ka tsela ea meta-ring cleavage. Ka mokhoa o ts'oanang, S. paucimobilis 2322 e tlalehiloe e sebelisa NDO ho hydroxylate 2-methylnaphthalene, e kenngoang oxidized ho etsa methyl salicylate le methylcatechol (Dutta et al., 1998).
Li-acid tsa Naphthoic (tse nketsoeng sebaka/tse sa nkeloang sebaka) ke lihlahisoa tse entsoeng ka chefo/phetoho ea bio tse entsoeng nakong ea ho senyeha ha methylnaphthalene, phenanthrene le anthracene 'me li lokolloa sebakeng sa temo se sebelisitsoeng. Ho tlalehiloe hore mobu o arolang Stenotrophomonas maltophilia CSV89 o khona ho fetola 1-naphthoic acid e le mohloli oa khabone (Phale et al., 1995). Metabolism e qala ka dihydroxylation ea lesale le monko o monate ho theha 1,2-dihydroxy-8-carboxynaphthalene. Diol e hlahisoang e oxidized ho ea catechol ka 2-hydroxy-3-carboxybenzylidenepyruvate, 3-formylsalicylic acid, 2-hydroxyisophthalic acid le salicylic acid 'me e kena tseleng e bohareng ea khabone ka tsela ea meta-ring cleavage (Setšoantšo sa 3).
Carbaryl ke chefo e bolaeang dikokwana-hloko ya naphthyl carbamate. Ho tloha Phetohelong ya Botala India ka bo-1970, tshebediso ya manyolo a dikhemikhale le dibolaya dikokwana-hloko e lebisitse keketsehong ya mesi e tswang ho polycyclic aromatic hydrocarbon (PAH) e tswang mehloding ya temo e seng ya ntlha (Pingali, 2012; Duttagupta et al., 2020). Ho hakanngwa hore 55% (dihekthere tse 85,722,000) ya masimo ohle a dijalo India e phekolwa ka chefo e bolayang dikokwana-hloko ya dikhemikhale. Dilemong tse hlano tse fetileng (2015–2020), lekala la temo la India le sebedisitse karolelano ya ditone tse 55,000 ho isa ho tse 60,000 tsa dibolaya dikokwana-hloko selemo le selemo (Lefapha la Dikoporasi le Boiketlo ba Balemi, Lefapha la Temo, Mmuso wa India, Phato 2020). Thoteng ya Gangetic e ka leboya le bohareng (dinaha tse nang le baahi ba bangata le bongata ba baahi), tshebediso ya chefo e bolayang dikokwana-hloko dijalong e atile haholo, mme dibolaya dikokwana-hloko di atile haholo. Carbaryl (1-naphthyl-N-methylcarbamate) ke sebolaya-dikokwana-hloko sa carbamate se nang le mahlakore a mangata, se nang le chefo e itekanetseng ho isa ho e matla haholo se sebediswang temong ya India ka karolelano ya ditone tse 100–110. Hangata se rekiswa tlasa lebitso la kgwebo la Sevin mme se sebedisetswa ho laola dikokonyana (di-aphid, bohlwa ba mollo, di-fleas, dikokonyana, di-spider le tse ding tse ngata tse senyang dikokwana-hloko tsa kantle) tse amang mefuta e fapaneng ya dijalo (poone, soya, k'hothone, ditholwana le meroho). Dikokwana-hloko tse ding tse kang Pseudomonas (NCIB 12042, 12043, C4, C5, C6, C7, Pseudomonas putida XWY-1), Rhodococcus (NCIB 12038), Sphingobacterium spp. (CF06), Burkholderia (C3), Micrococcus le Arthrobacter le tsona di ka sebediswa ho laola dikokonyana tse ding tse senyang dikokwana-hloko. Ho tlalehiloe hore RC100 e ka senya carbaryl (Larkin le Day, 1986; Chapalamadugu le Chaudhry, 1991; Hayatsu et al., 1999; Swetha le Phale, 2005; Trivedi et al., 2017). Tsela ea ho senyeha ha carbaryl e ithutiloe ka botlalo maemong a biochemical, enzymatic le a liphatsa tsa lefutso linthong tse arohaneng tsa mobu tsa Pseudomonas sp. Strains C4, C5 le C6 (Swetha le Phale, 2005; Trivedi et al., 2016) (Setšoantšo sa 3). Tsela ea metabolism e qala ka hydrolysis ea ester bond ke carbaryl hydrolase (CH) ho theha 1-naphthol, methylamine le carbon dioxide. 1-naphthol ebe e fetoloa ho ba 1,2-dihydroxynaphthalene ke 1-naphthol hydroxylase (1-NH2), e fetoloang hape ka tsela e bohareng ea khabone ka salicylate le gentisate. Ho tlalehiloe hore libaktheria tse ling tse senyang carbaryl li e fetola salicylic acid ka ho petsoha ha lesale la catechol ortho (Larkin le Day, 1986; Chapalamadugu le Chaudhry, 1991). Haholo-holo, libaktheria tse senyang naphthalene li fetola salicylic acid haholo-holo ka catechol, athe libaktheria tse senyang carbaryl li khetha ho fetola salicylic acid ka tsela ea gentisate.
Naphthalenesulfonic acid/disulfonic acid le naphthylaminesulfonic acid derivatives di ka sebediswa e le di-intermediate tlhahisong ya azo daes, di-wetting agents, dispersants, jj. Le hoja metsoako ena e na le chefo e tlase ho batho, ditekolo tsa cytotoxicity di bontshitse hore di kotsi ho ditlhapi, daphnia le algae (Greim et al., 1994). Baemedi ba mofuta wa Pseudomonas (mefuta ya A3, C22) ba tlalehilwe hore ba qala metabolism ka ho kopanya habeli lesale la aromatic le nang le sehlopha sa sulfonic acid ho theha dihydrodiol, e fetolelwang hape ho 1,2-dihydroxynaphthalene ka ho arohana ha sehlopha sa sulfite ka boithatelo (Brilon et al., 1981). 1,2-dihydroxynaphthalene e hlahang e kenngwa ka tsela ya naphthalene ya kgale, ke hore, tsela ya catechol kapa gentisate (Setshwantsho sa 4). Ho bontšitsoe hore aminonaphthalenesulfonic acid le hydroxynaphthalenesulfonic acid li ka senyeha ka ho feletseng ke sehlopha se kopaneng sa baktheria se nang le litsela tse tlatsanang tsa catabolic (Nortemann et al., 1986). Ho bontšitsoe hore setho se seng sa sehlopha se kopanyang se tlosa aminonaphthalenesulfonic acid kapa hydroxynaphthalenesulfonic acid ka 1,2-dioxygenation, ha aminosalicylate kapa hydroxysalicylate e lokolloa sebakeng sa temo e le metabolite e sa feleng 'me hamorao e nkuoa ke litho tse ling tsa sehlopha. Naphthalenedisulfonic acid e batla e le polar empa e ka senyeha hampe 'me ka hona e ka fetoloa ka litsela tse fapaneng. Desulfurization ea pele e etsahala nakong ea regioselective dihydroxylation ea lesale la aromatic le sehlopha sa sulfonic acid; ho tlosoa ha sulfurization ya bobedi ho etsahala nakong ya hydroxylation ya 5-sulfosalicylic acid ke salicylic acid 5-hydroxylase ho theha gentisic acid, e kenang tseleng e bohareng ya khabone (Brilon et al., 1981) (Setshwantsho sa 4). Dienzyme tse ikarabellang bakeng sa ho senyeha ha naphthalene le tsona di ikarabella bakeng sa metabolism ya naphthalene sulfonate (Brilon et al., 1981; Keck et al., 2006).
Setšoantšo sa 4. Litsela tsa metabolism bakeng sa ho senyeha ha naphthalene sulfonate. Lipalo tse ka hare ho li-circles li emela li-enzyme tse ikarabellang bakeng sa metabolism ea naphthyl sulfonate, tse tšoanang/tse ts'oanang le li-enzyme tse hlalositsoeng ho Setšoantšo sa 3.
Li-PAH tse boima bo tlase ba limolek'hule (LMW-PAHs) lia fokotsoa, ​​ha li rate metsi 'me ha li qhibilihe hantle, ka hona ha li kotsing ea ho senyeha/ho senyeha ha tlhaho. Leha ho le joalo, likokoana-hloko tsa aerobic li khona ho e oxida ka ho monya oksijene ea limolek'hule (O2). Li-enzyme tsena haholo-holo ke tsa sehlopha sa li-oxidoreductase 'me li ka etsa liketso tse fapaneng tse kang aromatic ring hydroxylation (mono- kapa dihydroxylation), dehydrogenation le aromatic ring cleavage. Lihlahisoa tse fumanoang liketsong tsena li boemong bo phahameng ba oxidation 'me li fetoloa habonolo ka tsela e bohareng ea khabone (Phale et al., 2020). Li-enzyme tse tseleng ea ho senyeha li tlalehiloe li sa khone ho inducite. Mosebetsi oa li-enzyme tsena o tlase haholo kapa ha o na thuso ha lisele li holisoa mehloling e bonolo ea khabone joalo ka glucose kapa li-acid tsa organic. Tafole ea 3 e akaretsa li-enzyme tse fapaneng (oxygenases, hydrolases, dehydrogenases, oxidases, jj.) tse amehang metabolism ea naphthalene le lihlahisoa tsa eona.
Tafole ea 3. Litšobotsi tsa lik'hemik'hale tsa li-enzyme tse ikarabellang bakeng sa ho senyeha ha naphthalene le lintho tse tsoang ho eona.
Lithuto tsa radioisotope (18O2) li bontšitse hore ho kenngoa ha molek'hule O2 ka har'a masale a monko ke li-oxygenase ke mohato oa bohlokoa ka ho fetisisa ho qaleng ho bola ha motsoako (Hayaishi et al., 1955; Mason et al., 1955). Ho kenngoa ha athomo e le 'ngoe ea oksijene (O) ho tsoa oksijeneng ea molek'hule (O2) ka har'a substrate ho qalisoa ke li-monooxygenase tse tsoang tlhahong kapa tse tsoang kantle ho naha (tseo hape li bitsoang hydroxylases). Athomo e 'ngoe ea oksijene e fokotsoa hore e be metsi. Li-monooxygenase tse tsoang kantle ho naha li fokotsa flavin ka NADH kapa NADPH, athe ho li-endomonooxygenase flavin e fokotsoa ke substrate. Boemo ba hydroxylation bo fella ka mefuta-futa ea ho thehoa ha sehlahisoa. Mohlala, salicylate 1-hydroxylase hydroxylates salicylic acid boemong ba C1, e etsa catechol. Ka lehlakoreng le leng, salicylate 5-hydroxylase e nang le likarolo tse ngata (e nang le reductase, ferredoxin, le oxygenase subunits) e etsa hydroxylates salicylic acid boemong ba C5, e leng se etsang gentisic acid (Yamamoto et al., 1965).
Dioxygenases di kenyelletsa diathomo tse pedi tsa O2 ka hara substrate. Ho itshetlehile ka dihlahiswa tse entsweng, di arotswe ka di-ring hydroxylating di-diooxygenase le di-ring cleaving di-diooxygenase. Di-ring hydroxylating di-diooxygenase di fetola di-aromatic substrates hore e be di-cis-dihydrodiols (mohlala, naphthalene) mme di atile hara dibaktheria. Ho fihlela jwale, ho bontshitswe hore diphedi tse nang le di-ring hydroxylating di-diooxygenase di kgona ho hola mehloding e fapaneng ya khabone e nkhang hamonate, mme di-enzyme tsena di arotswe e le NDO (naphthalene), toluene dioxygenase (TDO, toluene), le biphenyl dioxygenase (BPDO, biphenyl). NDO le BPDO ka bobedi di ka susumetsa ho kenngwa ha oxidation habeli le hydroxylation ya ketane ya lehlakore ya di-hydrocarbon tse fapaneng tsa aromatic tsa polycyclic (toluene, nitrotoluene, xylene, ethylbenzene, naphthalene, biphenyl, fluorene, indole, methylnaphthalene, naphthalenesulfonate, phenanthrene, anthracene, acetophenone, jj.) (Boyd le Sheldrake, 1998; Phale et al., 2020). NDO ke sistimi ya dikarolo tse ngata e nang le oxidoreductase, ferredoxin, le karolo e sebetsang e nang le oxygenase (Gibson le Subramanian, 1984; Resnick et al., 1996). Yuniti ya catalytic ya NDO e na le subunit e kgolo ya α le subunit e nyane ya β e hlophisitsoeng ka sebopeho sa α3β3. NDO ke ea lelapa le leholo la li-oxygenase 'me α-subunit ea eona e na le sebaka sa Rieske [2Fe-2S] le tšepe e seng ea heme ea mononuclear, e khethollang ho hlaka ha substrate ea NDO (Parales et al., 1998). Ka tloaelo, potolohong e le 'ngoe ea catalytic, lielektrone tse peli tse tsoang phokotsong ea pyridine nucleotide li fetisetsoa ho ion ea Fe(II) sebakeng se sebetsang ka reductase, ferredoxin le sebaka sa Rieske. Lintho tse fokotsang tse lekanang li kenya oksijene ea limolek'hule tšebetsong, e leng ntho ea bohlokoa bakeng sa substrate dihydroxylation (Ferraro et al., 2005). Ho fihlela joale, ke li-NDO tse 'maloa feela tse hloekisitsoeng le ho khetholloa ka botlalo ho tsoa mefuteng e fapaneng' me taolo ea liphatsa tsa lefutso ea litsela tse amehang ho senyeheng ha naphthalene e ithutiloe ka botlalo (Resnick et al., 1996; Parales et al., 1998; Karlsson et al., 2003). Dioxygenase tse kgaolang lesale (dienzyme tse kgaolang lesale kapa ortho-ring le dienzyme tse kgaolang lesale kapa meta-ring) di sebetsa hodima metsoako ya aromatic e nang le hydroxylated. Mohlala, dioxygenase e kgaolang lesale kapa meta-ring ke catechol-1,2-dioxygenase, athe dioxygenase e kgaolang lesale ke catechol-2,3-dioxygenase (Kojima et al., 1961; Nozaki et al., 1968). Ntle le di-oxygenase tse fapaneng, ho boetse ho na le di-dehydrogenase tse fapaneng tse ikarabellang bakeng sa ho kgaola ha dihydrodiols tse aromatic, dialcohols le aldehydes mme di sebedisa NAD+/NADP+ e le diamoheli tsa dielektrone, e leng tse ding tsa dienzyme tsa bohlokwa tse amehang metabolism (Gibson le Subramanian, 1984; Shaw le Harayama, 1990; Fahle et al., 2020).
Li-enzyme tse kang li-hydrolase (li-esterase, li-amidase) ke sehlopha sa bobeli sa bohlokoa sa li-enzyme tse sebelisang metsi ho arola maqhama a covalent le ho bontša ho hlaka ho pharaletseng ha substrate. Carbaryl hydrolase le li-hydrolase tse ling li nkoa e le likarolo tsa periplasm (transmembrane) ho litho tsa libaktheria tsa Gram-negative (Kamini et al., 2018). Carbaryl e na le khokahano ea amide le ester; ka hona, e ka hydrolyzed ke esterase kapa amidase ho theha 1-naphthol. Carbaryl ho Rhizobium rhizobium strain AC10023 le Arthrobacter strain RC100 li tlalehiloe li sebetsa e le esterase le amidase, ka ho latellana. Carbaryl ho Arthrobacter strain RC100 le eona e sebetsa e le amidase. Ho bontšitsoe hore RC100 e hydrolyze meriana e mene e bolaeang likokoanyana ea sehlopha sa N-methylcarbamate joalo ka carbaryl, methomyl, mefenamic acid le XMC (Hayaatsu et al., 2001). Ho tlalehiloe hore CH ho Pseudomonas sp. C5pp e ka sebetsa ho carbaryl (mosebetsi oa 100%) le 1-naphthyl acetate (mosebetsi oa 36%), empa eseng ho 1-naphthylacetamide, e leng se bontšang hore ke esterase (Trivesi et al., 2016).
Lithuto tsa biochemical, mekhoa ea taolo ea enzyme, le tlhahlobo ea liphatsa tsa lefutso li bontšitse hore liphatsa tsa lefutso tsa naphthalene tse senyehang li na le li-unit tse peli tse laoloang tse ka inducible kapa "operons": nah ("tsela e holimo", e fetolang naphthalene ho ba salicylic acid) le sal ("tsela e tlase", e fetolang salicylic acid ho ea tseleng e bohareng ea khabone ka catechol). Salicylic acid le li-analogue tsa eona li ka sebetsa e le li-inducer (Shamsuzzaman le Barnsley, 1974). Ha ho na le glucose kapa li-acid tsa organic, operon ea hatelloa. Setšoantšo sa 5 se bontša mokhatlo o felletseng oa liphatsa tsa lefutso oa ho senyeha ha naphthalene (ka sebopeho sa operon). Mefuta/mefuta e 'maloa e reheletsoeng ea liphatsa tsa lefutso tsa nah (ndo/pah/dox) e hlalositsoe' me ea fumanoa e na le homology e phahameng ea tatellano (90%) har'a mefuta eohle ea Pseudomonas (Abbasian et al., 2016). Liphatsa tsa lefutso tsa tsela e holimo ea naphthalene ka kakaretso li hlophisitsoe ka tatellano ea tumellano joalo ka ha ho bontšitsoe Setšoantšong sa 5A. Jini e 'ngoe, nahQ, le eona e tlalehiloe e ameha metabolism ea naphthalene 'me hangata e ne e le pakeng tsa nahC le nahE, empa mosebetsi oa eona oa 'nete o ntse o sa hlakisoe. Ka mokhoa o ts'oanang, jini ea nahY, e ikarabellang bakeng sa chemotaxis e utloang naphthalene, e fumanoe pheletsong e ka thoko ea nah operon ho litho tse ling. Ho Ralstonia sp., jini ea U2 e kenyang glutathione S-transferase (gsh) e fumanoe e le pakeng tsa nahAa le nahAb empa ha ea ka ea ama litšobotsi tsa ts'ebeliso ea naphthalene (Zylstra et al., 1997).
Setšoantšo sa 5. Tlhophiso ea liphatsa tsa lefutso le mefuta-futa e bonoang nakong ea ho senyeha ha naphthalene har'a mefuta ea baktheria; (A) Tsela e ka holimo ea naphthalene, metabolism ea naphthalene ho ea ho salicylic acid; (B) Tsela e ka tlase ea naphthalene, salicylic acid ka catechol ho ea tseleng e bohareng ea khabone; (C) salicylic acid ka gentisate ho ea tseleng e bohareng ea khabone.
"Tsela e ka tlase" (sal operon) hangata e na le nahGTHINLMOKJ mme e fetola salicylate ho ba pyruvate le acetaldehyde ka tsela ya catechol metaring cleavage. Jini ya nahG (e ngotseng salicylate hydroxylase) e fumanwe e bolokilwe pheletsong e haufi ya operon (Setshwantsho sa 5B). Ha e bapiswa le mefuta e meng e senyang naphthalene, ho P. putida CSV86 nah le sal operon di kopane mme di amana haufi haholo (hoo e ka bang 7.5 kb). Dibaktheria tse ding tse se nang Gram, tse kang Ralstonia sp. U2, Polaromonas naphthalenivorans CJ2, le P. putida AK5, naphthalene e metabolitwa e le metabolite e bohareng ya carbon ka tsela ya gentisate (ka sebopeho sa sgp/nag operon). Khasete ea liphatsa tsa lefutso hangata e emeloa ka mokhoa oa nagAaGHabAcAdBFCQEDJI, moo nagR (e kenyang khoutu ea taolo ea mofuta oa LysR) e leng pheletsong e ka holimo (Setšoantšo sa 5C).
Carbaryl e kena potolohong ea khabone e bohareng ka metabolism ea 1-naphthol, 1,2-dihydroxynaphthalene, salicylic acid, le gentisic acid (Setšoantšo sa 3). Ho latela lithuto tsa liphatsa tsa lefutso le metabolism, ho 'nile ha etsoa tlhahiso ea ho arola tsela ena ka "holimo" (phetoho ea carbaryl ho salicylic acid), "bohareng" (phetoho ea salicylic acid ho ea gentisic acid), le "tlase" (phetoho ea gentisic acid ho ea lipakeng tsa tsela ea khabone e bohareng) (Singh et al., 2013). Tlhahlobo ea genomic ea C5pp (supercontig A, 76.3 kb) e senotse hore gene ea mcbACBDEF e ameha phetohong ea carbaryl ho ea ho salicylic acid, e lateloa ke mcbIJKL phetohong ea salicylic acid ho ea ho gentisic acid, le mcbOQP phetohong ea gentisic acid ho ea ho central carbon intermediates (fumarate le pyruvate, Trivedi et al., 2016) (Setšoantšo sa 6).
Ho tlalehiloe hore li-enzyme tse amehang ho senyeheng ha li-hydrocarbon tse nkhang hamonate (ho kenyeletsoa naphthalene le salicylic acid) li ka susumetsoa ke metsoako e tsamaellanang le eona 'me tsa thibeloa ke mehloli e bonolo ea khabone joalo ka glucose kapa li-acid tsa organic (Shingler, 2003; Phale et al., 2019, 2020). Har'a litsela tse fapaneng tsa metabolism ea naphthalene le li-derivative tsa eona, litšobotsi tsa taolo tsa naphthalene le carbaryl li ithutiloe ho isa bohōleng bo itseng. Bakeng sa naphthalene, liphatsa tsa lefutso litseleng tse holimo le tse tlase li laoloa ke NahR, molaoli oa trans-acting positive oa mofuta oa LysR. E hlokahala bakeng sa ho kenngoa ha gene ea nah ka salicylic acid le tlhahiso ea eona ea boemo bo holimo e latelang (Yen le Gunsalus, 1982). Ho feta moo, lithuto li bontšitse hore integrative host factor (IHF) le XylR (sigma 54-dependent transcriptional regulator) le tsona li bohlokoa bakeng sa ho kenngoa tšebetsong ha gene ka transcriptional metabolism ea naphthalene (Ramos et al., 1997). Lithuto li bontšitse hore li-enzyme tsa tsela ea ho bula ea catechol meta-ring, e leng catechol 2,3-dioxygenase, li hlahisoa boteng ba naphthalene le/kapa salicylic acid (Basu et al., 2006). Lithuto li bontšitse hore li-enzyme tsa tsela ea ho bula ea catechol ortho-ring, e leng catechol 1,2-dioxygenase, li hlahisoa boteng ba benzoic acid le cis,cis-muconate (Parsek et al., 1994; Tover et al., 2001).
Mofuteng oa C5pp, liphatsa tsa lefutso tse hlano, mcbG, mcbH, mcbN, mcbR le mcbS, li kenya melaoana ea taolo ea lelapa la LysR/TetR la balaoli ba transcriptional ba ikarabellang bakeng sa ho laola ho senyeha ha carbaryl. Lefu la lefutso le tšoanang la mcbG le fumanoe le amana haufi-ufi le PhnS ea taolo ea mofuta oa LysR (58% amino acid identity) e amehang metabolism ea phenanthrene ho Burkholderia RP00725 (Trivesi et al., 2016). Lefu la lefutso la mcbH le fumanoe le ameha tseleng e mahareng (phetoho ea salicylic acid ho ea ho gentisic acid) 'me ke la taolo ea transcriptional ea mofuta oa LysR NagR/DntR/NahR ho Pseudomonas le Burkholderia. Litho tsa lelapa lena li tlalehiloe li hlokomela salicylic acid e le molek'hule e itseng ea effector bakeng sa ho kenngoa ha liphatsa tsa lefutso tsa ho senyeha. Ka lehlakoreng le leng, liphatsa tsa lefutso tse tharo, mcbN, mcbR le mcbS, tse leng tsa balaoli ba phetolelo ba mofuta oa LysR le TetR, li ile tsa fumanoa tseleng e theohelang (metabolite ea carbon pathway ea gentisate-central).
Ho prokaryotes, mekhoa ea phetisetso ea liphatsa tsa lefutso tse otlolohileng (ho fumana, ho fapanyetsana, kapa ho fetisetsa) ka li-plasmid, li-transposon, li-prophage, lihlekehleke tsa genomic, le likarolo tse kopaneng tsa motsoako (ICE) ke lisosa tse kholo tsa ho ba plasticity li-genome tsa baktheria, e leng se lebisang ho fumaneng kapa ho lahleheloa ke mesebetsi/litšobotsi tse itseng. E lumella libaktheria ho ikamahanya ka potlako le maemo a fapaneng a tikoloho, e fana ka melemo e ka bang teng ea metabolism e ikamahanyang le moamoheli, joalo ka ho senyeha ha metsoako ea monko o monate. Liphetoho tsa metabolism hangata li finyelloa ka ho lokisa li-operon tsa ho senyeha, mekhoa ea tsona ea taolo, le li-enzyme tse ikhethang, tse nolofalletsang ho senyeha ha mefuta e mengata ea metsoako ea monko o monate (Nojiri et al., 2004; Phale et al., 2019, 2020). Li-cassette tsa liphatsa tsa lefutso bakeng sa ho senyeha ha naphthalene li fumanoe li le holim'a mefuta e fapaneng ea likarolo tse tsamaeang joalo ka li-plasmid (tse kopantsoeng le tse sa kopaneng), li-transposon, li-genome, li-ICE, le metsoako ea mefuta e fapaneng ea libaktheria (Setšoantšo sa 5). Ho Pseudomonas G7, di-operon tsa nah le sal tsa plasmid NAH7 di ngotswe ka tsela e tshwanang mme ke karolo ya transposon e nang le sekoli e hlokang transposase Tn4653 bakeng sa ho sisinyeha (Sota et al., 2006). Mofuteng wa Pseudomonas NCIB9816-4, jini e fumanwe ho conjugative plasmid pDTG1 e le di-operon tse pedi (tse ka bang 15 kb tse arohaneng) tse ngotsweng ka mahlakoreng a fapaneng (Dennis le Zylstra, 2004). Mofuteng wa Pseudomonas putida AK5, plasmid pAK5 e sa kopanyeng e kenya enzyme e ikarabellang bakeng sa ho senyeha ha naphthalene ka tsela ya gentisate (Izmalkova et al., 2013). Mofuteng oa Pseudomonas PMD-1, nah operon e fumaneha ho chromosome, athe sal operon e fumaneha ho conjugative plasmid pMWD-1 (Zuniga et al., 1981). Leha ho le joalo, ho Pseudomonas stutzeri AN10, liphatsa tsohle tsa lefutso tsa naphthalene degradation (nah le sal operon) li fumaneha ho chromosome 'me ho ka etsahala hore li amoheloe ka transposition, recombination, le rearrangment events (Bosch et al., 2000). Ho Pseudomonas sp. CSV86, nah le sal operon li fumaneha ho genome ka mokhoa oa ICE (ICECSV86). Sebopeho se sirelelitsoe ke tRNAGly se lateloa ke ho pheta-pheta ka ho toba ho bontšang libaka tsa ho kopanya/ho hokela (attR le attL) le integrase e kang phage e fumanehang lipheletsong ka bobeli tsa tRNAGly, kahoo e tšoana ka sebopeho le karolo ea ICEclc (ICEclcB13 ho Pseudomonas knackmusii bakeng sa ho senyeha ha chlorocatechol). Ho tlalehiloe hore liphatsa tsa lefutso ho ICE li ka fetisetsoa ka ho kopana ka maqhubu a tlase haholo a phetisetso (10-8), ka hona li fetisetsa thepa ea ho senyeha ho moamoheli (Basu le Phale, 2008; Phale et al., 2019).
Bongata ba liphatsa tsa lefutso tse ikarabellang bakeng sa ho senyeha ha carbaryl li fumaneha ho plasmids. Arthrobacter sp. RC100 e na le li-plasmids tse tharo (pRC1, pRC2 le pRC300) tseo ho tsona li-plasmids tse peli tse kopanetsoeng, pRC1 le pRC2, li kenyang lienzyme tse fetolelang carbaryl ho gentisate. Ka lehlakoreng le leng, lienzyme tse amehang phetohong ea gentisate ho metabolites ea carbon e bohareng li fumaneha ho chromosome (Hayaatsu et al., 1999). Libaktheria tsa mofuta oa Rhizobium. Strain AC100, e sebelisetsoang ho fetola carbaryl ho 1-naphthol, e na le plasmid pAC200, e jereng gene ea cehA e kenyang CH e le karolo ea transposon ea Tnceh e pota-potiloeng ke tatellano e kang ea element (istA le istB) (Hashimoto et al., 2002). Ho mofuta oa Sphingomonas CF06, jini ea ho senyeha ha carbaryl ho lumeloa hore e teng ho li-plasmid tse hlano: pCF01, pCF02, pCF03, pCF04, le pCF05. Ho tšoana ha DNA ea li-plasmid tsena ho phahame, ho bontša boteng ba ketsahalo ea ho pheta-pheta ha liphatsa tsa lefutso (Feng et al., 1997). Ho mofuta oa carbaryl-degrading symbiont o entsoeng ka mefuta e 'meli ea Pseudomonas, mofuta oa 50581 o na le plasmid pCD1 (50 kb) e kenyang jini ea mcd carbaryl hydrolase, athe plasmid e kopanyang ho mofuta oa 50552 e kenya enzyme e senyang 1-naphthol (Chapalamadugu le Chaudhry, 1991). Ho mofuta oa Achromobacter WM111, jini ea mcd furadan hydrolase e fumaneha ho plasmid ea 100 kb (pPDL11). Jini ena e bontshitswe e le teng ho di-plasmid tse fapaneng (100, 105, 115 kapa 124 kb) dibaktheriang tse fapaneng tse tswang dibakeng tse fapaneng tsa jeokrafi (Parekh et al., 1995). Ho Pseudomonas sp. C5pp, dijini tsohle tse ikarabellang bakeng sa ho senyeha ha carbaryl di fumaneha ka hara genome e nkang 76.3 kb ya tatellano (Trivesi et al., 2016). Tlhahlobo ya genome (6.15 Mb) e senotse boteng ba di-MGE tse 42 le di-GEI tse 36, tseo ho tsona di-MGE tse 17 di neng di le ka hara supercontig A (76.3 kb) ka karolelano ya dikahare tsa G+C tse sa lekanang (54–60 mol%), e leng se bontshang diketsahalo tse ka bang teng tsa phetisetso ya dijini tse rapameng (Trivesi et al., 2016). P. putida XWY-1 e bontsha tokisetso e tshwanang ya dijini tse senyang carbaryl, empa dijini tsena di fumaneha ka hara plasmid (Zhu et al., 2019).
Ntle le bokgoni ba metabolism maemong a biochemical le genomic, dikokwana-hloko di boetse di bontsha thepa kapa dikarabelo tse ding tse kang chemotaxis, thepa ya phetoho ya bokahodimo ba sele, ho arolwa ha dikarolo, tshebediso e kgethehileng, tlhahiso ya biosurfactant, jj., tse di thusang ho sebedisa ditshila tse nkhang hamonate ka katleho dibakeng tse silafetseng (Setshwantsho sa 7).
Setšoantšo sa 7. Maano a fapaneng a karabelo ea lisele tsa libaktheria tse ntle tse senyang hydrocarbon tse nkhang hamonate bakeng sa ho bola ha metsoako e litšila ea kantle ho naha ka katleho.
Likarabelo tsa chemotactic li nkoa e le mabaka a ntlafatsang ho senyeha ha litšila tse phelang libakeng tse silafetseng tse sa tšoaneng. (2002) li bontšitse hore chemotaxis ea Pseudomonas sp. G7 ho naphthalene e ekelitse sekhahla sa ho senyeha ha naphthalene lits'ebetsong tsa metsing. Mofuta oa mofuta oa tlhaho oa G7 o ile oa senya naphthalene ka potlako haholo ho feta mofuta oa phetoho o haelloang ke chemotaxis. Protheine ea NahY (li-amino acid tse 538 tse nang le topology ea lera) e fumanoe e kopantsoe le liphatsa tsa lefutso tsa metacleavage ho plasmid ea NAH7, 'me joalo ka li-transducer tsa chemotaxis, protheine ena e bonahala e sebetsa e le chemoreceptor bakeng sa ho senyeha ha naphthalene (Grimm le Harwood 1997). Phuputso e 'ngoe ea Hansel et al. (2009) e bontšitse hore protheine ke chemotactic, empa sekhahla sa eona sa ho senyeha se holimo. (2011) o bontšitse karabelo ea chemotactic ea Pseudomonas (P. putida) ho naphthalene e nang le khase, moo ho hasana ha mokhahlelo oa khase ho ileng ha fella ka phallo e tsitsitseng ea naphthalene ho ea liseleng, e neng e laola karabelo ea chemotactic ea lisele. Bafuputsi ba sebelisitse boitšoaro bona ba chemotactic ho bopa likokoana-hloko tse neng li tla ntlafatsa sekhahla sa ho senyeha. Lithuto li bontšitse hore litsela tsa chemosensory li boetse li laola mesebetsi e meng ea sele joalo ka karohano ea sele, taolo ea potoloho ea sele, le ho thehoa ha biofilm, ka hona li thusa ho laola sekhahla sa ho senyeha. Leha ho le joalo, ho sebelisa thepa ena (chemotaxis) bakeng sa ho senyeha ka katleho ho sitisoa ke mathata a 'maloa. Mathata a maholo ke: (a) li-receptor tse fapaneng tsa paralogous li lemoha metsoako/ligand tse tšoanang; (b) boteng ba li-receptor tse ling, ke hore, tropism ea matla; (c) liphapang tse kholo tsa tatellano libakeng tsa kutlo tsa lelapa le le leng la li-receptor; le (d) khaello ea tlhahisoleseling mabapi le liprotheine tse kholo tsa sensor ea baktheria (Ortega et al., 2017; Martin-Mora et al., 2018). Ka linako tse ling, ho bola ha di-hydrocarbon tse nkhang hamonate ho hlahisa di-metabolite/mefuta-tshebetso tse ngata, tse ka bang chemotactic bakeng sa sehlopha se seng sa dibaktheria empa di nyonyeha ho tse ding, e leng se thatafatsang tshebetso le ho feta. Ho hlwaya dikamano tsa di-ligand (di-hydrocarbon tse nkhang hamonate) le di-receptor tsa dikhemikhale, re hahile diprotheine tsa sensor tse kopantsweng (PcaY, McfR, le NahY) ka ho kopanya di-sensor le di-signal domains tsa Pseudomonas putida le Escherichia coli, tse shebaneng le di-receptor bakeng sa di-aromatic acid, di-intermediate tsa TCA, le naphthalene, ka ho latellana (Luu et al., 2019).
Tlas'a tšusumetso ea naphthalene le li-hydrocarbon tse ling tse nang le aromatic tse ngata (li-PAH), sebopeho sa lera la baktheria le botšepehi ba likokoana-hloko li fetoha haholo. Lithuto li bontšitse hore naphthalene e sitisa tšebelisano ea ketane ea acyl ka likamano tsa hydrophobic, ka hona e eketsa ho ruruha le ho phalla ha lera (Sikkema et al., 1995). Ho loantša phello ena e mpe, libaktheria li laola ho phalla ha lera ka ho fetola karolelano le motsoako oa asiti ea mafura pakeng tsa iso/anteiso branched-chain fatty acids le isomerizing cis-unsaturated fatty acids ho li-trans-isomers tse tsamaellanang (Heipieper le de Bont, 1994). Ho Pseudomonas stutzeri e lengoang kalafong ea naphthalene, karolelano ea asiti ea mafura e saturated ho ea ho e saturated e eketsehile ho tloha ho 1.1 ho ea ho 2.1, athe ho Pseudomonas JS150 karolelano ena e eketsehile ho tloha ho 7.5 ho ea ho 12.0 (Mrozik et al., 2004). Ha di hodiswa ho naphthalene, disele tsa Achromobacter KA tsa 3-5 di bontshitse ho kopana ha disele ho potoloha dikristale tsa naphthalene le phokotseho ya tjhaja ya bokahodimo ba sele (ho tloha ho -22.5 ho isa ho -2.5 mV) e tsamaellanang le ho kobeha ha cytoplasm le vacuolization, e leng se bontshang diphetoho sebopehong sa sele le thepa ya bokahodimo ba sele (Mohapatra et al., 2019). Le hoja diphetoho tsa sele/bokahodimo di amana ka ho toba le ho nkuwa ha ditshila tse nkhang hamonate hamolemo, maano a amehang a bioengineering ha a so ntlafatsoe ka botlalo. Ho tshwarwa ha sebopeho sa sele ha ho a sebediswa hangata ho ntlafatsa ditshebetso tsa baeloji (Volke le Nikel, 2018). Ho ntshwa ha dijini tse amang karohano ya sele ho baka diphetoho sebopehong sa sele. Ho ntshwa ha dijini tse amang karohano ya sele ho baka diphetoho sebopehong sa sele. Ho ntshwa ha dijini tse amang karohano ya sele ho baka diphetoho sebopehong sa sele. Ho Bacillus subtilis, protheine ya septum ya sele SepF e bontshitswe e ameha ho thehweng ha septum mme e a hlokahala bakeng sa mehato e latelang ya karohano ya sele, empa ha se jini ya bohlokwa. Ho hlakoloa ha liphatsa tsa lefutso tse kenyang peptide glycan hydrolases ho Bacillus subtilis ho bakile ho hola ha sele, keketseho ea sekhahla sa kholo e itseng, le ntlafatso ea bokhoni ba tlhahiso ea li-enzyme (Cui et al., 2018).
Ho aroloa ha tsela ea ho senyeha ha carbaryl ho sisintswe ho fihlella ho senyeha ho sebetsang hantle ha mefuta ea Pseudomonas C5pp le C7 (Kamini et al., 2018). Ho sisintswe hore carbaryl e iswe sebakeng sa periplasmic ka septum ea lera le ka ntle le/kapa ka li-porins tse hasang. CH ke enzyme ea periplasmic e susumetsang hydrolysis ea carbaryl ho 1-naphthol, e tsitsitseng haholoanyane, e sa tšabeng metsi le e chefo haholoanyane. CH e fumaneha sebakeng sa periplasm 'me e na le kamano e tlase bakeng sa carbaryl, kahoo e laola ho thehoa ha 1-naphthol, ka hona e thibela ho bokellana ha eona liseleng le ho fokotsa chefo ea eona liseleng (Kamini et al., 2018). 1-naphthol e hlahang e isoa cytoplasm ho pholletsa le lera le ka hare ka ho arola le/kapa ho hasana, ebe e fetoloa hydroxylated ho 1,2-dihydroxynaphthalene ke enzyme ea high-affinity 1NH bakeng sa metabolism e eketsehileng tseleng e bohareng ea carbon.
Leha dikokwana-hloko di na le bokgoni ba lefutso le metabolism ba ho senya mehlodi ya khabone ya xenobiotic, sebopeho sa maemo a tshebediso ya tsona (ke hore, tshebediso e kgethehileng ya mehlodi e bonolo ho feta e rarahaneng ya khabone) ke tshitiso e kgolo ho bola ha diphedi. Boteng le tshebediso ya mehlodi e bonolo ya khabone e fokotsa dijini tse kenyang dienzyme tse senyang mehlodi ya khabone e rarahaneng/e sa kgethwang jwalo ka di-PAH. Mohlala o ithutwang hantle ke hore ha glucose le lactose di fepuwa hammoho ho Escherichia coli, glucose e sebediswa ka katleho ho feta lactose (Jacob le Monod, 1965). Ho tlalehilwe hore Pseudomonas e senya mefuta e fapaneng ya di-PAH le metswako ya xenobiotic e le mehlodi ya khabone. Tatellano ya tshebediso ya mehlodi ya khabone ho Pseudomonas ke di-organic acid > glucose > metswako e nkhang hamonate (Hylemon le Phibbs, 1972; Collier et al., 1996). Leha ho le jwalo, ho na le mokhelo. Ho thahasellisang ke hore, Pseudomonas sp. CSV86 e bonts'a sebopeho se ikhethang sa maemo se sebelisang ka ho khetheha li-hydrocarbon tse nkhang hamonate (benzoic acid, naphthalene, jj.) ho fapana le glucose mme se kopanya li-hydrocarbon tse nkhang hamonate le li-acid tsa organic (Basu et al., 2006). Baktheria ena, liphatsa tsa lefutso tsa ho senyeha le ho tsamaisoa ha li-hydrocarbon tse nkhang hamonate ha li fokotsoe esita le ha ho na le mohloli oa bobeli oa khabone joalo ka glucose kapa li-acid tsa organic. Ha li holisoa ka har'a glucose le aromatic hydrocarbons medium, ho ile ha hlokomeloa hore liphatsa tsa lefutso tsa ho tsamaisoa ha glucose le metabolism li fokotsoe, li-hydrocarbon tse nkhang hamonate li sebelisitsoe mohatong oa pele oa log, 'me glucose e sebelisitsoe mohatong oa bobeli oa log (Basu et al., 2006; Choudhary et al., 2017). Ka lehlakoreng le leng, boteng ba li-acid tsa organic ha boa ka ba ama tlhahiso ea metabolism ea aromatic hydrocarbon, kahoo baktheria ena e lebelletsoe ho ba mofuta o ka khethoang bakeng sa lithuto tsa ho bola ha bio (Phale et al., 2020).
Ho tsebahala hantle hore phetoho ya hydrocarbon e ka baka kgatello ya oxidative le ho eketseha ha dienzyme tsa antioxidant dikokwana-hlokong. Ho senyeha ha naphthalene ka tsela e sa sebetseng hantle diseleng tsa mohato o sa sisinyeheng le boteng ba metsoako e chefo ho lebisa ho thehweng ha mefuta ya oksijene e arabelang (ROS) (Kang et al. 2006). Kaha dienzyme tse senyang naphthalene di na le dihlopha tsa tshepe le sebabole, tlasa kgatello ya oxidative, tshepe e ka hara diprotheine tsa heme le tshepe le sebabole di tla oxidized, e leng se lebisang ho se sebetseng ha protheine. Ferredoxin-NADP+ reductase (Fpr), hammoho le superoxide dismutase (SOD), e buella karabelo ya reversible redox pakeng tsa NADP+/NADPH le dimolek'hule tse pedi tsa ferredoxin kapa flavodoxin, ka hona e tlosa ROS mme e tsosolosa setsi sa tshepe le sebabole tlasa kgatello ya oxidative (Li et al. 2006). Ho tlalehiloe hore Fpr le SodA (SOD) ka bobeli ho Pseudomonas li ka bakoa ke khatello ea oxidative, 'me keketseho ea mesebetsi ea SOD le catalase e bonoe mefuteng e mene ea Pseudomonas (O1, W1, As1, le G1) nakong ea kholo tlas'a maemo a ekelitsoeng ke naphthalene (Kang et al., 2006). Lithuto li bontšitse hore ho eketsoa ha li-antioxidants tse kang ascorbic acid kapa tšepe ea ferrous (Fe2+) ho ka eketsa sekhahla sa kholo ea naphthalene. Ha Rhodococcus erythropolis e hola mofuteng oa naphthalene, phetisetso ea liphatsa tsa lefutso tsa cytochrome P450 tse amanang le khatello ea oxidative ho kenyeletsoa le sodA (Fe/Mn superoxide dismutase), sodC (Cu/Zn superoxide dismutase), le recA e ile ea eketseha (Sazykin et al., 2019). Tlhahlobo ea protheine ea bongata e bapisang ea lisele tsa Pseudomonas tse lengoang ka har'a naphthalene e bontšitse hore ho eketsa liprotheine tse fapaneng tse amanang le karabelo ea khatello ea oxidative ke leano la ho sebetsana le khatello ea maikutlo (Herbst et al., 2013).
Ho tlalehiloe hore likokoana-hloko li hlahisa li-biosurfactants tlas'a ts'ebetso ea mehloli ea khabone e sa hlokeng metsi. Li-surfactants tsena ke metsoako e sebetsang ea holim'a metsi a leoatle e ka etsang li-aggregates libakeng tsa oli-metsi kapa tsa moea-metsi. Sena se khothalletsa ho qhibiliha ho sa lokelang 'me se nolofatsa ho monngoa ha li-hydrocarbon tse nkhang hamonate, e leng se fellang ka ho bola ha biogradation ka katleho (Rahman et al., 2002). Ka lebaka la litšobotsi tsena, li-biosurfactants li sebelisoa haholo liindastering tse fapaneng. Ho eketsoa ha li-surfactants tsa lik'hemik'hale kapa li-biosurfactants litso tsa baktheria ho ka ntlafatsa bokhoni le sekhahla sa ho senyeha ha hydrocarbon. Har'a li-biosurfactants, li-rhamnolipide tse hlahisoang ke Pseudomonas aeruginosa li ithutiloe ka botlalo 'me li khetholloa (Hisatsuka et al., 1971; Rahman et al., 2002). Ho phaella moo, mefuta e meng ea li-biosurfactants e kenyelletsa lipopeptides (li-mucin tse tsoang ho Pseudomonas fluorescens), emulsifier 378 (e tsoang ho Pseudomonas fluorescens) (Rosenberg le Ron, 1999), trehalose disaccharide lipids tse tsoang ho Rhodococcus (Ramdahl, 1985), lichenin e tsoang ho Bacillus (Saraswathy le Hallberg, 2002), le surfactant e tsoang ho Bacillus subtilis (Siegmund le Wagner, 1991) le Bacillus amyloliquefaciens (Zhi et al., 2017). Li-surfactants tsena tse matla li bontšitsoe li fokotsa tsitsipano ea bokaholimo ho tloha ho 72 dynes/cm ho ea ho ka tlase ho 30 dynes/cm, e leng se lumellang ho monngoa ha hydrocarbon hamolemo. Ho tlalehiloe hore Pseudomonas, Bacillus, Rhodococcus, Burkholderia le mefuta e meng ea baktheria li ka hlahisa li-biosurfactants tse fapaneng tsa rhamnolipid le glycolipid ha li lengoa ka har'a naphthalene le methylnaphthalene media (Kanga et al., 1997; Puntus et al., 2005). Pseudomonas maltophilia CSV89 e ka hlahisa biosurfactant ea extracellular Biosur-Pm ha e lengoa ka metsoako ea aromatic joalo ka naphthoic acid (Phale et al., 1995). Kinetics ea ho thehoa ha Biosur-Pm e bontšitse hore tlhahiso ea eona ke ts'ebetso e itšetlehileng ka kholo le pH. Ho fumanoe hore bongata ba Biosur-Pm bo hlahisoang ke lisele tse pH e sa nke lehlakore bo ne bo le holimo ho feta ba pH 8.5. Lisele tse holisitsoeng ho pH 8.5 li ne li le hydrophobic haholo 'me li ne li e-na le kamano e phahameng bakeng sa metsoako ea aromatic le aliphatic ho feta lisele tse holisitsoeng ho pH 7.0. Ho Rhodococcus spp. N6, karolelano e phahameng ea khabone ho ea ho naetrojene (C:N) le moeli oa tšepe ke maemo a matle bakeng sa tlhahiso ea li-biosurfactants tse tsoang kantle ho naha (Mutalik et al., 2008). Ho entsoe boiteko ba ho ntlafatsa biosynthesis ea li-biosurfactants (li-surfactin) ka ho ntlafatsa mefuta le ho belisoa. Leha ho le joalo, tekanyo ea surfactant sebakeng sa temo e tlase (1.0 g/L), e leng se bakang phephetso bakeng sa tlhahiso e kholo (Jiao et al., 2017; Wu et al., 2019). Ka hona, mekhoa ea boenjiniere ba liphatsa tsa lefutso e sebelisitsoe ho ntlafatsa biosynthesis ea eona. Leha ho le joalo, phetoho ea eona ea boenjiniere e thata ka lebaka la boholo bo boholo ba operon (∼25 kb) le taolo e rarahaneng ea biosynthesis ea sistimi ea ho lemoha quorum (Jiao et al., 2017; Wu et al., 2019). Liphetoho tse 'maloa tsa boenjiniere ba liphatsa tsa lefutso li entsoe libaktheria tsa Bacillus, haholo-holo tse reretsoeng ho eketsa tlhahiso ea surfactin ka ho nkela sebaka sa promoter (srfA operon), ho hlahisa protheine ea surfactin e tsoang kantle ho naha YerP le lintlha tsa taolo ComX le PhrC (Jiao et al., 2017). Leha ho le joalo, mekhoa ena ea boenjiniere ba liphatsa tsa lefutso e fihletse phetoho e le 'ngoe kapa tse' maloa tsa liphatsa tsa lefutso 'me ha e so fihle tlhahiso ea khoebo. Ka hona, ho hlokahala thuto e eketsehileng ea mekhoa ea ntlafatso e thehiloeng tsebong.
Lithuto tsa ho bola ha PAH di etswa haholo-holo tlasa maemo a tlwaelehileng a laboratori. Leha ho le jwalo, dibakeng tse silafetseng kapa dibakeng tse silafetseng, mabaka a mangata a abiotic le a biotic (mocheso, pH, oksijene, ho fumaneha ha dikotla, ho ba teng ha substrate, di-xenobiotic tse ding, thibelo ya ho qetela ya sehlahiswa, jj.) a bontshitswe a fetola le ho susumetsa bokgoni ba ho bola ha dikokwana-hloko.
Mocheso o na le phello e kholo ho bola ha PAH. Ha mocheso o ntse o eketseha, mahloriso a oksijene e qhibilihisitsoeng aa fokotseha, e leng se amang metabolism ea likokoana-hloko tsa aerobic, kaha li hloka oksijene ea limolek'hule e le e 'ngoe ea li-substrate tsa oksijene tse etsang liketso tsa hydroxylation kapa ring cleavage. Hangata ho hlokomeloa hore mocheso o phahameng o fetola li-PAH tsa motsoali hore e be metsoako e chefo haholo, ka hona o thibela bola ha biogradation (Muller et al., 1998).
Ho hlokometsoe hore libaka tse ngata tse silafetseng tsa PAH li na le boleng bo feteletseng ba pH, joalo ka libaka tse silafetseng tsa drainage ea merafo ea asiti (pH 1-4) le libaka tsa khase ea tlhaho/mashala tse silafalitsoeng ke alkaline leachate (pH 8-12). Maemo ana a ka ama ts'ebetso ea ho bola ha biogradation ka botebo. Ka hona, pele ho sebelisoa likokoana-hloko bakeng sa ho lokisa bioremediation, ho khothalletsoa ho fetola pH ka ho eketsa lik'hemik'hale tse loketseng (tse nang le bokhoni ba ho fokotsa oxidation bo itekanetseng ho isa ho bo tlase haholo) joalo ka ammonium sulfate kapa ammonium nitrate bakeng sa mobu oa alkaline kapa kalaka ka calcium carbonate kapa magnesium carbonate bakeng sa libaka tse nang le asiti (Bowlen et al. 1995; Gupta le Sar 2020).
Phepelo ea oksijene sebakeng se amehileng ke ntlha e fokotsang sekhahla bakeng sa ho bola ha PAH. Ka lebaka la maemo a redox a tikoloho, lits'ebetso tsa ho lokisa lintho tse phelang sebakeng seo hangata li hloka ho kenngoa ha oksijene ho tsoa mehloling e kantle (ho lema, ho fokotsa moea, le ho eketsoa ha lik'hemik'hale) (Pardieck et al., 1992). Odenkranz et al. (1996) ba bontšitse hore ho eketsoa ha magnesium peroxide (motsoako o lokollang oksijene) ho aquifer e silafetseng ho ka lokisa metsoako ea BTEX ka katleho. Phuputso e 'ngoe e batlisisitse ho senyeha ha phenol le BTEX sebakeng seo ka aquifer e silafetseng ka ho enta sodium nitrate le ho haha ​​​​liliba tsa ho ntša metsi ho fihlela bioremediation e sebetsang (Bewley le Webb, 2001).