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Carl E Cerniglia - One of the best experts on this subject based on the ideXlab platform.
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Biotransformation of 1-nitrobenzo[e]pyrene by the fungus Cunninghamella elegans
Journal of Industrial Microbiology & Biotechnology, 1999Co-Authors: J V Pothuluri, Peter P. Fu, James P Freeman, Carl E CernigliaAbstract:Biotransformation of 1-nitrobenzo[e]pyrene (1-nitro-BeP), an environmental pollutant derived from the nitration of a non-carcinogen, benzo[e]pyrene, was studied using the fungus Cunninghamella elegans ATCC 36112. After 72 h incubation, 89% of 1-nitro-[3H]BeP added had been metabolized to two major metabolites. These metabolites were separated by reversed-phase high performance liquid chromatography and identified by 1H NMR, UV-visible, and mass spectral techniques as 1-nitro-6-benzo[e]pyrenylsulfate and 1-nitrobenzo[e]pyrene 6-O-β-glucopyranoside. Comparison of the Fungal Metabolism patterns of 1-nitro-BeP and BeP indicates that the nitro group at the C-1 position of BeP altered the regioselectivity of Metabolism.
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Fungal Metabolism of nitrofluoranthenes.
Journal of Toxicology and Environmental Health, 1998Co-Authors: J V Pothuluri, Daniel R. Doerge, Mona I. Churchwell, Peter P. Fu, Carl E CernigliaAbstract:Metabolism of 2-nitrofluoranthene (2-NFA), one of the most abundant and genotoxic environmental pollutants in air, and of a mixture of 2-nitrofluoranthene and 3-nitrofluoranthene (3-NFA) was studied using (1) the fungus Cunninghamella elegans ATCC 36112 and (2) rat liver microsomes. The Fungal metabolites were separated by reversed phase high-performance liquid chromatography (HPLC) and identified by 'H nuclear magnetic resonance (NMR) spectrometry, ultraviolet (UV)-visible spectroscopy, and online atmospheric-pressure chemical ionization/mass spectrometry (APCI/MS). The fungus metabolized 82% of 2-nitro-( 3 H)-fluoranthene to 2-nitrofluoranthene 8-sulfate and 2-nitrofluoranthene 9-sulfate. Metabolism of a mixture of 2- and 3-nitrofluoranthene by C. elegans similarly produced 2-nitrofluoranthene 8- and 9-sulfate and 3-nitrofluoranthene 8- and 9-sulfate as major metabolites. In addition, a glucoside conjugate of 3-hydroxy-2-nitrofluoranthene was tentatively identified by APCl/MS analysis. When rat liver microsomes were incubated with a mixture of 2- and 3-nitrofluoranthene for 1 h, in addition to the trans-7,8- and 9,10-dihydrodiols reported previously for 2-nitrofluoran-thene, several novel metabolites were produced including 2-nitrofluoranthene trans-4,5-dihydrodiol and 2-nitrofluoranthene trans-8,9-dihydrodiol, the trans-4,5-dihydrodiol of 3-nitrofluoranthene, and phenolic products of both 2- and 3-nitrofluoranthene. The Fungal Metabolism of the 2- and 3-nitrofluoranthene mixture was similar to the Metabolism of individual nitrofluoranthenes; however, the mammalian Metabolism of the nitrofluoranthene mixture showed differences in regioselectivity at positions C4, C5, C8, and C9.
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Fungal Metabolism of polycyclic aromatic hydrocarbons past present and future applications in bioremediation
Journal of Industrial Microbiology & Biotechnology, 1997Co-Authors: Carl E CernigliaAbstract:This article examines the importance of non-ligninolytic and ligninolytic fungi in the bioremediation of polycyclic aromatic hydrocarbon contaminated wastes. The research from the initial studies in Dave Gibson’s laboratory to the present are discussed.
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Fungal Metabolism of 3 nitrofluoranthene
Journal of Toxicology and Environmental Health, 1994Co-Authors: J V Pothuluri, Frederick E Evans, Thomas M Heinze, Carl E CernigliaAbstract:We investigated the Metabolism of 3‐nitrofluoranthene by filamentous fungus, Cunning‐hamella elegans ATCC 36112. Cunninghamella elegans metabolized about 72% of the 3‐nitro[3,4‐14C]fluoranthene added during 144 h of incubation to 2 major metabolites. These metabolites were separated by reversed‐phase high‐performance liquid chromatography and identified as 3‐nitrofluoranthene‐8‐sulfate and 3‐nitrofluoranthene‐9‐sulfate by ‘H nuclear magnetic resonance, UV‐visible, and mass spectral techniques. These results, in conjunction with previous studies on the Fungal Metabolism of fluoranthene, indicate that the nitro substituent at the C‐3 position of fluoranthene sterically hinders epoxidation and shifts Metabolism to the C‐8 and C‐9 positions. Since the phenolic microsomal metabolites of 3‐nitrofluoranthene are mutagenic, the formation of sulfate conjugates of 8‐ and 9‐hydroxy‐3‐nitrofluoranthene by C. elegans suggests that the Fungal metabolic pathways may be beneficial for detoxification of this ubiquitous po...
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Fungal Metabolism of acenaphthene by cunninghamella elegans
Applied and Environmental Microbiology, 1992Co-Authors: J V Pothuluri, Frederick E Evans, J P Freeman, Carl E CernigliaAbstract:The filamentous fungus Cunninghamella elegans ATCC 36112 metabolized within 72 h of incubation approximately 64% of the [1,8-14C]acenaphthene added. The radioactive metabolites were extracted with ethyl acetate and separated by thin-layer chromatography and reversed-phase high-performance liquid chromatography. Seven metabolites were identified by 1H nuclear magnetic resonance, UV, and mass spectral techniques as 6-hydroxyacenaphthenone (24.8%), 1,2-acenaphthenedione (19.9%), trans-1,2-dihydroxyacenaphthene (10.3%), 1,5-dihydroxyacenaphthene (2.7%), 1-acenaphthenol (2.4%), 1-acenaphthenone (2.1%), and cis-1,2-dihydroxyacenaphthene (1.8%). Parallel experiments with rat liver microsomes indicated that the major metabolite formed from acenaphthene by rat liver microsomes was 1-acenaphthenone. The Fungal Metabolism of acenaphthene was similar to bacterial and mammalian Metabolism, since the primary site of enzymatic attack was on the two carbons of the five-member ring.
J V Pothuluri - One of the best experts on this subject based on the ideXlab platform.
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Biotransformation of 1-nitrobenzo[e]pyrene by the fungus Cunninghamella elegans
Journal of Industrial Microbiology & Biotechnology, 1999Co-Authors: J V Pothuluri, Peter P. Fu, James P Freeman, Carl E CernigliaAbstract:Biotransformation of 1-nitrobenzo[e]pyrene (1-nitro-BeP), an environmental pollutant derived from the nitration of a non-carcinogen, benzo[e]pyrene, was studied using the fungus Cunninghamella elegans ATCC 36112. After 72 h incubation, 89% of 1-nitro-[3H]BeP added had been metabolized to two major metabolites. These metabolites were separated by reversed-phase high performance liquid chromatography and identified by 1H NMR, UV-visible, and mass spectral techniques as 1-nitro-6-benzo[e]pyrenylsulfate and 1-nitrobenzo[e]pyrene 6-O-β-glucopyranoside. Comparison of the Fungal Metabolism patterns of 1-nitro-BeP and BeP indicates that the nitro group at the C-1 position of BeP altered the regioselectivity of Metabolism.
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Fungal Metabolism of nitrofluoranthenes.
Journal of Toxicology and Environmental Health, 1998Co-Authors: J V Pothuluri, Daniel R. Doerge, Mona I. Churchwell, Peter P. Fu, Carl E CernigliaAbstract:Metabolism of 2-nitrofluoranthene (2-NFA), one of the most abundant and genotoxic environmental pollutants in air, and of a mixture of 2-nitrofluoranthene and 3-nitrofluoranthene (3-NFA) was studied using (1) the fungus Cunninghamella elegans ATCC 36112 and (2) rat liver microsomes. The Fungal metabolites were separated by reversed phase high-performance liquid chromatography (HPLC) and identified by 'H nuclear magnetic resonance (NMR) spectrometry, ultraviolet (UV)-visible spectroscopy, and online atmospheric-pressure chemical ionization/mass spectrometry (APCI/MS). The fungus metabolized 82% of 2-nitro-( 3 H)-fluoranthene to 2-nitrofluoranthene 8-sulfate and 2-nitrofluoranthene 9-sulfate. Metabolism of a mixture of 2- and 3-nitrofluoranthene by C. elegans similarly produced 2-nitrofluoranthene 8- and 9-sulfate and 3-nitrofluoranthene 8- and 9-sulfate as major metabolites. In addition, a glucoside conjugate of 3-hydroxy-2-nitrofluoranthene was tentatively identified by APCl/MS analysis. When rat liver microsomes were incubated with a mixture of 2- and 3-nitrofluoranthene for 1 h, in addition to the trans-7,8- and 9,10-dihydrodiols reported previously for 2-nitrofluoran-thene, several novel metabolites were produced including 2-nitrofluoranthene trans-4,5-dihydrodiol and 2-nitrofluoranthene trans-8,9-dihydrodiol, the trans-4,5-dihydrodiol of 3-nitrofluoranthene, and phenolic products of both 2- and 3-nitrofluoranthene. The Fungal Metabolism of the 2- and 3-nitrofluoranthene mixture was similar to the Metabolism of individual nitrofluoranthenes; however, the mammalian Metabolism of the nitrofluoranthene mixture showed differences in regioselectivity at positions C4, C5, C8, and C9.
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Fungal Metabolism of 2-nitrofluorene
Journal of Toxicology and Environmental Health, 1996Co-Authors: J V PothuluriAbstract:Nitrated polycyclic aromatic hydrocarbons (nitro-PAHs) are direct-acting mutagens and carcinogens that are considered a risk to human health. We investigated the Metabolism of 2- nitrofluorene by the fungus Cunninghamella elegans ATCC 36112. At 144 h of incubation, C. elegans had metabolized about 81% of the [9-14C]-2-nitrofluorene, resulting in 6 metabolites. The major metabolites were separated by reversed-phase high-performance liquid chromatography and identified by 1H NMR, ultraviolet (UV)-visible, and mass spectral analyses as 2-nitro-9-fluorenol, 2-nitro-9-fluorenone, 6-hydroxy-2-nitrofluorene, and sulfate conjugates of 7-hydroxy-2-nitro-9-fluorenone and 7-hydroxy-2-nitrofluorene. 2-Nitro-9-fluorenol accounted for about 62% of the total Metabolism. For comparison with the microbial system, experiments with liver microsomes of rats pretreated with 3-methylcholanthrene were conducted. Microsom al incubations indicated formation of phenolic and ring-hydroxylated products of 2-nitrofluorene. 2-Nitroflu...
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Fungal Metabolism of 3 nitrofluoranthene
Journal of Toxicology and Environmental Health, 1994Co-Authors: J V Pothuluri, Frederick E Evans, Thomas M Heinze, Carl E CernigliaAbstract:We investigated the Metabolism of 3‐nitrofluoranthene by filamentous fungus, Cunning‐hamella elegans ATCC 36112. Cunninghamella elegans metabolized about 72% of the 3‐nitro[3,4‐14C]fluoranthene added during 144 h of incubation to 2 major metabolites. These metabolites were separated by reversed‐phase high‐performance liquid chromatography and identified as 3‐nitrofluoranthene‐8‐sulfate and 3‐nitrofluoranthene‐9‐sulfate by ‘H nuclear magnetic resonance, UV‐visible, and mass spectral techniques. These results, in conjunction with previous studies on the Fungal Metabolism of fluoranthene, indicate that the nitro substituent at the C‐3 position of fluoranthene sterically hinders epoxidation and shifts Metabolism to the C‐8 and C‐9 positions. Since the phenolic microsomal metabolites of 3‐nitrofluoranthene are mutagenic, the formation of sulfate conjugates of 8‐ and 9‐hydroxy‐3‐nitrofluoranthene by C. elegans suggests that the Fungal metabolic pathways may be beneficial for detoxification of this ubiquitous po...
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Fungal Metabolism of acenaphthene by cunninghamella elegans
Applied and Environmental Microbiology, 1992Co-Authors: J V Pothuluri, Frederick E Evans, J P Freeman, Carl E CernigliaAbstract:The filamentous fungus Cunninghamella elegans ATCC 36112 metabolized within 72 h of incubation approximately 64% of the [1,8-14C]acenaphthene added. The radioactive metabolites were extracted with ethyl acetate and separated by thin-layer chromatography and reversed-phase high-performance liquid chromatography. Seven metabolites were identified by 1H nuclear magnetic resonance, UV, and mass spectral techniques as 6-hydroxyacenaphthenone (24.8%), 1,2-acenaphthenedione (19.9%), trans-1,2-dihydroxyacenaphthene (10.3%), 1,5-dihydroxyacenaphthene (2.7%), 1-acenaphthenol (2.4%), 1-acenaphthenone (2.1%), and cis-1,2-dihydroxyacenaphthene (1.8%). Parallel experiments with rat liver microsomes indicated that the major metabolite formed from acenaphthene by rat liver microsomes was 1-acenaphthenone. The Fungal Metabolism of acenaphthene was similar to bacterial and mammalian Metabolism, since the primary site of enzymatic attack was on the two carbons of the five-member ring.
J Augustin - One of the best experts on this subject based on the ideXlab platform.
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Fungal Metabolism and detoxification of polycyclic aromatic hydrocarbons a review
Bioresource Technology, 1994Co-Authors: D Muncnerova, J AugustinAbstract:Abstract The polycyclic aromatic hydrocarbons (PAH) are highly hazardous pollutants found in soil, sediments and air, and which are produced in the process of organic matter combustion. Some of them are acutely toxic, mutagenic or carcinogenic. The group of fungi which includes Aspergillus ochraceus, Cunninghamella elegans, Cunninghamella echinulata, Phanerochaete chrysosporium, Bjerkandera sp., Trametes versicolor and the yeast Saccharomyces cerevisiae have the ability to oxidize or transform polycyclic aromatic hydrocarbons and render them non-toxic.
Satoshi Tahara - One of the best experts on this subject based on the ideXlab platform.
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A Journey of Twenty-Five Years through the Ecological Biochemistry of Flavonoids
Bioscience Biotechnology and Biochemistry, 2007Co-Authors: Satoshi TaharaAbstract:The ecological biochemistry of flavonoids, in which I have been engaged for 25 years, is summarized in this review article. The review covers (1) a survey of rare bio-active flavonoids in higher plants; (2) the Fungal Metabolism of prenylated flavonoids; (3) flavonoids antidoting against benzimidazole fungicides; (4) dihydroflavonol ampelopsin in Salix sachalinensis as a feeding stimulant towards willow beetles; and (5) flavones as signaling substances in the life-cycle development of the phytopathogenic Peronosporomycete Aphanomyces cochlioides, a cause of spinach root rot and sugar beet damping-off diseases. Finally recent trends in the ecological biochemistry of flavonoids are briefly described.
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Fad-dependent epoxidase as a key enzyme in Fungal Metabolism of prenylated flavonoids
Phytochemistry, 1997Co-Authors: Mitsuharu Tanaka, Satoshi TaharaAbstract:Crude protein extracts from Botrytis cinerea preincubated with 6-prenylnaringenin (6-PN) for 20 hr catalysed the prenyl epoxidation of 7-O-methyl-luteone. The resulting epoxide was non-enzymatically and slowly converted into the corresponding dihydrofurano derivative in a buffer solution at pH 7.5. Preparation of cell-free extracts in the presence of 6-PN from the mycelia without preincubation with 6-PN hardly showed the epoxidizing activity. These facts revealed that the substrate analogue 6-PN has a role as an enzyme inducer rather than stabilizer. The enzyme reaction depends on molecular oxygen and NADPH. Low amounts of FAD were necessary for maximal enzyme activity. The enzymatic activity was not inhibited by various inhibitors of cytochrome P-450 tested, in addition to carbon monoxide and cytochrome c. The results indicated that this enzyme does not belong to the monooxygenases dependent on cytochrome P-450, but to those dependent on FAD. About half of the total enzyme activity was found in the 125 000 g supernatant, but the specific activity for the epoxidation reaction in the 125 000 g pellet was 3.7-fold higher than in the soluble fraction. The enzyme showed high specificity to monoprenyl isoflavones. Finally, a preliminary experiment using a cell-free system from white lupin hypocotyls resulted in formation of small amounts of an epoxide corresponding to 7-O-methyl-luteone used as the substrate.
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Fungal Metabolism of prenylated flavonoids
Phytochemistry, 1997Co-Authors: Satoshi Tahara, Mitsuharu Tanaka, Wolfgang BarzAbstract:Abstract When incubated in liquid culture with Aspergillus flavus , the prenylated flavanone 6-prenylnaringenin [(2 S )-6-(3,3-dimethylallyl)-5,7,4′-trihydroxyflavanone] was converted into 2,3-dihydrodihydroxy-prenyl-substituted naringenin, 6-prenylnaringenin hydrate, and dihydrofurano-substituted naringenin. The latter metabolite was also found as the major metabolite of 6-prenylnaringenin in Botrytis cinerea culture. Further experiments using a strain of Ascochyta rabiei pathogenic to chickpea, which can metabolize non-planar isoflavonoid pterocarpans, revealed that 6-prenylnaringenin gave only a minute amount of metabolites, whilst the prenylated isoflavone luteone [6-(3,3-dimethylallyl)-5,7,2′,4′-tetrahydroxyisoflavone] was slowly converted into the corresponding dihydrofuranoisoflavone.
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Substrate specificity in the Fungal Metabolism of prenylated flavonoids
Zeitschrift für Naturforschung C, 1991Co-Authors: Satoshi Tahara, John L. Ingham, Junya MizutaniAbstract:Isolation and identification of compounds resulting from the Fungal Metabolism of topazolin, piscerythrone and piscidone. The fourth substrate, lupinifolinol was recovered unchanged from cultures of both Aspergillus flavus and Botrytis cinerea
Frederick E Evans - One of the best experts on this subject based on the ideXlab platform.
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Fungal Metabolism of 3 nitrofluoranthene
Journal of Toxicology and Environmental Health, 1994Co-Authors: J V Pothuluri, Frederick E Evans, Thomas M Heinze, Carl E CernigliaAbstract:We investigated the Metabolism of 3‐nitrofluoranthene by filamentous fungus, Cunning‐hamella elegans ATCC 36112. Cunninghamella elegans metabolized about 72% of the 3‐nitro[3,4‐14C]fluoranthene added during 144 h of incubation to 2 major metabolites. These metabolites were separated by reversed‐phase high‐performance liquid chromatography and identified as 3‐nitrofluoranthene‐8‐sulfate and 3‐nitrofluoranthene‐9‐sulfate by ‘H nuclear magnetic resonance, UV‐visible, and mass spectral techniques. These results, in conjunction with previous studies on the Fungal Metabolism of fluoranthene, indicate that the nitro substituent at the C‐3 position of fluoranthene sterically hinders epoxidation and shifts Metabolism to the C‐8 and C‐9 positions. Since the phenolic microsomal metabolites of 3‐nitrofluoranthene are mutagenic, the formation of sulfate conjugates of 8‐ and 9‐hydroxy‐3‐nitrofluoranthene by C. elegans suggests that the Fungal metabolic pathways may be beneficial for detoxification of this ubiquitous po...
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Fungal Metabolism of acenaphthene by cunninghamella elegans
Applied and Environmental Microbiology, 1992Co-Authors: J V Pothuluri, Frederick E Evans, J P Freeman, Carl E CernigliaAbstract:The filamentous fungus Cunninghamella elegans ATCC 36112 metabolized within 72 h of incubation approximately 64% of the [1,8-14C]acenaphthene added. The radioactive metabolites were extracted with ethyl acetate and separated by thin-layer chromatography and reversed-phase high-performance liquid chromatography. Seven metabolites were identified by 1H nuclear magnetic resonance, UV, and mass spectral techniques as 6-hydroxyacenaphthenone (24.8%), 1,2-acenaphthenedione (19.9%), trans-1,2-dihydroxyacenaphthene (10.3%), 1,5-dihydroxyacenaphthene (2.7%), 1-acenaphthenol (2.4%), 1-acenaphthenone (2.1%), and cis-1,2-dihydroxyacenaphthene (1.8%). Parallel experiments with rat liver microsomes indicated that the major metabolite formed from acenaphthene by rat liver microsomes was 1-acenaphthenone. The Fungal Metabolism of acenaphthene was similar to bacterial and mammalian Metabolism, since the primary site of enzymatic attack was on the two carbons of the five-member ring.
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stereoselective Fungal Metabolism of methylated anthracenes
Applied and Environmental Microbiology, 1990Co-Authors: Carl E Cerniglia, J P Freeman, Peter P. Fu, Warren L Campbell, Frederick E EvansAbstract:The Metabolism of 9-methylanthracene (9-MA), 9-hydroxymethylanthracene (9-OHMA), and 9,10-dimethylanthracene (9,10-DMA) by the fungus Cunninghamella elegans ATCC 36112 is described. The metabolites were isolated by high-performance liquid chromatography and characterized by UV-visible, mass, and 1H nuclear magnetic resonance spectral techniques. The compounds 9-MA and 9,10-DMA were metabolized by two pathways, one involving initial hydroxylation of the methyl group(s) and the other involving epoxidation of the 1,2- and 3,4- aromatic double bond positions, followed by enzymatic hydration to form hydroxymethyl trans-dihydrodiols. For 9-MA Metabolism, the major metabolites identified were trans-1,2-dihydro-1,2-dihydroxy and trans-3,4-dihydro-3,4-dihydroxy derivatives of 9-MA and 9-OHMA. 9-OHMA was also metabolized to trans-1,2- and 3,4-dihydrodiol derivatives. The absolute configuration and optical purity were determined for each of the trans-dihydrodiols formed by Fungal Metabolism and compared with previously published circular dichroism spectral data obtained from rat liver microsomal Metabolism of 9-MA, 9-OHMA, and 9,10-DMA. Circular dichroism spectral analysis revealed that the major enantiomer for each dihydrodiol was predominantly in the S,S configuration, in contrast to the predominantly R,R configuration of the trans-dihydrodiol formed by mammalian enzyme systems. These results indicate that C. elegans metabolizes methylated anthracenes in a highly stereoselective manner that is different from that reported for rat liver microsomes.
