title: Plant compounds that induce polychlorinated biphenyl biodegradation by Arthrobacter sp. strain B1B.
abstract: Plant compounds that induced Arthrobacter sp. strain B1B to cometabolize polychlorinated biphenyls (PCBs) were identified by a screening assay based on the formation of a 4,4'-dichlorobiphenyl ring fission product. A chemical component of spearmint (Mentha spicata), l-carvone, induced Arthrobacter sp. strain B1B to cometabolize Aroclor 1242, resulting in significant degradation of 26 peaks in the mixture, including selected tetra- and pentachlorobiphenyls. Evidence for PCB biodegradation included peak disappearance, formation of a phenylhexdienoate ring fission product, and chlorobenzoate accumulation in the culture supernatant. Carvone was not utilized as a growth substrate and was toxic at concentrations of greater than 500 mg liter-1. Several compounds structurally related to l-carvone, including limonene, p-cymene, and isoprene, also induced cometabolism of PCBs by Arthrobacter sp. strain B1B. A structure-activity analysis showed that chemicals with an unsaturated p-menthane structural motif promoted the strongest cometabolism activity. These data suggest that certain plant-derived terpenoids may be useful for promoting enhanced rates of PCB biodegradation by soil bacteria.
authors.affiliation: Environmental Toxicology Graduate Program, University of California, Riverside 92521, USA.
authors.forename: E S
authors.initials: ES
authors.lastname: Gilbert
authors.forename: D E
authors.initials: DE
authors.lastname: Crowley
mesh_terms: D001140:Aroclors / Q000378:metabolism*; D001173:Arthrobacter / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism*; D001673:Biodegradation, Environmental; D002070:Butadienes / Q000378:metabolism / Q000494:pharmacology; D002723:Chlorobenzoates / Q000378:metabolism; D002849:Chromatography, Gas; D003470:Culture Media / Q000032:analysis; D000081005:Cyclohexane Monoterpenes; D053138:Cyclohexenes; D000081007:Cymenes; D045782:Hemiterpenes; D000077222:Limonene; D039821:Monoterpenes; D010420:Pentanes; D010936:Plant Extracts / Q000032:analysis* / Q000494:pharmacology*; D011078:Polychlorinated Biphenyls / Q000378:metabolism; D012987:Soil / Q000032:analysis; D013729:Terpenes / Q000378:metabolism / Q000494:pharmacology* / Q000633:toxicity
chemical_list: D001140:Aroclors; D002070:Butadienes; D002723:Chlorobenzoates; D003470:Culture Media; D000081005:Cyclohexane Monoterpenes; D053138:Cyclohexenes; D000081007:Cymenes; D045782:Hemiterpenes; D039821:Monoterpenes; D010420:Pentanes; D010936:Plant Extracts; D012987:Soil; D013729:Terpenes; C005059:isoprene; C007210:4-cymene; C027423:aroclor 1242; C006923:carvone; D000077222:Limonene; D011078:Polychlorinated Biphenyls