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排序方式: 共有429条查询结果,搜索用时 31 毫秒
81.
The ability of Rhizobium sp., isolated from Lablab purpureus to survive in soil containing a phenolic derivative catechol was investigated. It survived for 9 months in soil containing
catechol. In synthetic medium, Rhizobium sp. utilized catechol up to 10 mM as sole carbon source and catechol 1, 2-dioxygenase was present in the catechol grown cells. In the presence of organic acids
and sugars, catechol was co-metabolized; but catechol 1, 2-dioxygenase induction was inhibited. The ability of Rhizobium sp. to utilize various phenolic substances provides potential advantage to overcome the phenolic toxicants present in soils. 相似文献
82.
77 Ascomycetous, basidiomycetous as well as imperfect yeast strains of 46 different species and 20 genera were tested for growth with the substrates n-octane, n-hexadecane, and phenol. Of 59 yeast strains with ascomycetous cell wall structure 33 grew on hydrocarbons and 32 on phenol. No yeast strain out of 26 which are unable to use n-alkanes as a source of carbon and energy grew on phenol. In comparison with the latter 32 out of 33 n-hexadecane assimilating yeasts were also capable of using phenol. All n-octane utilizing yeasts of this group also assimilate phenol as a carbon source for growth.The correlation of the hydrocarbon assimilation with the phenol assimilation seems to be not so strong in the basidiomycetous yeasts. 7 out of 18 strains from this group grew on n-hexadecane and 13 on phenol.Furthermore, it could be shown that the use of hydrocarbons and phenol (as well as methanol) is strongly correlated with the coenzyme Q structure of the respective yeast strain.The results are discussed with respect to the particular chemical properties of the substrates used and the fact that coenzyme Q structure is considered to be an important marker of evolutionary relationships among yeasts. 相似文献
83.
Hamna Saleem Khadeeja Rehman Muhammad Afzal 《International journal of phytoremediation》2018,20(7):692-698
Phenol is a commonly found organic pollutant in industrial wastewaters. Its ecotoxicological significance is well known and, therefore, the compound is often required to be removed prior to discharge. In this study, plant-bacterial synergism was established in floating treatment wetlands (FTWs) in an attempt to maximize the removal of phenol from contaminated water. A common wetland plant, Typha domingensis, was vegetated on a floating mat and augmented with three phenol-degrading bacterial strains, Acinetobacter lwofii ACRH76, Bacillus cereus LORH97, and Pseudomonas sp. LCRH90, to develop FTWs for the remediation of water contaminated with phenol. All of the strains are known to have phenol-reducing properties, and grow well in FTWs. Results showed that T. domingensis was able to remove a small amount of phenol from the contaminated water; however, bacterial augmentation enhanced the removal potential significantly, i.e., 0.146 g/m2/day vs. 0.166 g/m2/day, respectively. Plant biomass also increased in the presence of bacterial consortia; and inoculated bacteria displayed successful colonization/survival in the rhizosphere, root interior and shoot interior of the plant. Similarly, highest reduction in chemical oxygen demand (COD), biochemical oxygen demand (BOD5), and total organic carbon (TOC) was achieved by the combined application of plants and bacteria. The study demonstrates that the plant-bacterial synergism in a FTW may be a more effective approach for the remediation of phenol-contaminated water. 相似文献
84.
Yusuke Amino Hidehiko Wakabayashi Satoko Akashi Yutaka Ishiwatari 《Bioscience, biotechnology, and biochemistry》2018,82(3):383-394
The structures, flavor-modifying effects, and CaSR activities of γ-glutamyl peptides comprising sulfur-containing amino acids were investigated. The chemical structures, including the linkage mode of the N-terminal glutamic acid, of γ-L-glutamyl-S-(2-propenyl)-L-cysteine (γ-L-glutamyl-S-allyl-L-cysteine) and its sulfoxide isolated from garlic were established by comparing their NMR spectra with those of authentic peptides prepared using chemical methods. Mass spectrometric analysis also enabled determination of the linkage modes in the glutamyl dipeptides by their characteristic fragmentation. In sensory evaluation, these peptides exhibited flavor-modifying effects (continuity) in umami solutions less pronounced but similar to that of glutathione. Furthermore, the peptides exhibited intrinsic flavor due to the sulfur-containing structure, which may be partially responsible for their flavor-modifying effects. In CaSR assays, γ-L-glutamyl-S-methyl-L-cysteinylglycine was most active, which indicates that the presence of a medium-sized aliphatic substituent at the second amino acid residue in γ-glutamyl peptides enhances CaSR activity. 相似文献
85.
Osamu Koiwai Kayo Hasada Yoshihiro Yasui Yuka Sakai Hiroshi Sato Tomomasa Watanabe 《Biochemical genetics》1995,33(3-4):111-122
The mouse gene for phenol UDP-glucuronosyltranferase (UDPGT;Ugtla1) was mapped at 42 cM on chromosome 1, a position identical to that of the gene for bilirubin UDPGT (Ugtla1), from linkage analysis of a three-point cross test withIdh-1, En-1, andUgtlal as marker genes. The cDNAs for mouse phenol and bilirubin UDPGTs, isolated after amplification by PCR, shared an identical 3-half region. Our results strongly suggest that mouse bilirubin and phenol UDPGTs are expressed from a single gene and involve alternative splicing events. We also detected duplication of the gene for phenol UDPGT in all mouse strains examined with the exception of MOL-MIT and SUB-SHH. 相似文献
86.
In polluted soil or ground water, inorganic nutrients such as nitrogen may be limiting, so that Monod kinetics for carbon limitation may not describe microbial growth and contaminant biodegradation rates. To test this hypothesis we measured14CO2 evolved by a pure culture ofAcinetobacter johnsonii degrading 120 µg14C-phenol per ml in saturated sand with molar carbon:nitrogen (CN) ratios ranging from 1.5 to 560. We fit kinetics models to the data using non-linear least squares regression. Phenol disappearance and population growth were also measured at CN1.5 and CN560.After a 5- to 10-hour lag period, most of the14CO2 evolution curves at all CN ratios displayed a sigmoidal shape, suggesting that the microbial populations grew. As CN ratio increased, the initial rate of14CO2 evolution decreased. Cell growth and phenol consumption occurred at both CN1.5 and CN560, and showed the same trends as the14CO2 data. A kinetics model assuming population growth limited by a single substrate best fit the14CO2 evolution data for CN1.5. At intermediate to high CN ratios, the data were best fit by a model originally formulated to describe no-growth metabolism of one substrate coupled with microbial growth on a second substrate. We suggest that this dual-substrate model describes linear growth on phenol while nitrogen is available and first-order metabolism of phenol without growth after nitrogen is depleted. 相似文献
87.
A crucial step in plant xanthone biosynthesis is the cyclization of an intermediate benzophenone to a xanthone. In cultured
cells of Centaurium erythraea RAFN, 2,3′,4,6-tetrahydroxybenzophenone (THBP) was shown to be intramolecularly coupled to 1,3,5-trihydroxyxanthone, whereas
in cell cultures of Hypericum androsaemum L. it was coupled to form the isomeric 1,3,7-trihydroxyxanthone. These regioselective cyclizations that occur ortho and para, respectively, to the 3′-hydroxy group of the benzophenone depend on cytochrome P
450, as shown by the effectiveness of established P
450 inhibitors and blue-light-reversible carbon monoxide inhibition. Furthermore, the reactions absolutely require NADPH and
O2. The underlying reaction mechanism is probably an oxidative phenol coupling that is catalyzed regioselectively by xanthone
synthases. These enzymes are proposed to be cytochrome P
450 oxidases. The intramolecular cyclizations of THBP to 1,3,5- and 1,3,7-trihydroxyxanthones catalyzed by the two xanthone synthases
represent an important branch point in the plant xanthone biosynthetic pathway.
Received: 24 March 1997 / Accepted: 28 May 1997 相似文献
88.
Maria Leja Anna Mareczek Renata Wojciechowska Stanisław Rożek 《Acta Physiologiae Plantarum》1997,19(3):319-325
Carrot root slices, stored for 4 days at 20 °C reacted with a strong accumulation of total phenols, especially chlorogenic
acid. A significant accumulation of isocoumarin content within the peel was observed in stored slices. Synthesis of phenols
was accompanied by an increase in phenylalanine ammonia lyase activity, wound induced respiration and ethylene production.
The great variability among the studied four cultivars was found concerning isocoumarin synthesis, PAL activity, respiration
rate and ethylene evolution, but less distinct in the case of chlorogenic acid accumulation.
The carrot slices obtained from freshly harvested roots were more sensitive to mechanical damage and short-term storage than
those prepared from roots previously stored. 相似文献
89.
Cem Yamali Mehtap Tugrak Muhammet Tanc 《Journal of enzyme inhibition and medicinal chemistry》2016,31(6):1678-1681
Phenolic mono Mannich bases [2-[4-hydroxy-3-(aminomethyl)benzylidene]-2,3-dihydro-1H-inden-1-one (8–15)] and bis Mannich bases [2-[4-hydroxy-3,5-bis(aminomethyl)benzylidene]-2, 3-dihydro-1H-inden-1-one (2–7)] were synthesized starting from 2-(4-hydroxybenzylidene)-2, 3-dihydro-inden-1-one (1). This study was designed in order to investigate the carbonic anhydrase (CA, EC 4.2.1.1) inhibitory properties of a library of compounds incorporating the phenol functional group. All prepared compounds showed a low inhibition percentages on both human (h) isoforms hCA I and hCA II compared to the reference sulfonamide acetazolamide. Mannich bases 2–15 had lower inhibition percentages than the compound 1 on hCA I and hCA II, except compound 14, which is a Mannich base derivative of dipropylamine, which had a similar inhibitory power as compound 1 on hCA II. All compounds synthesized 1–15 were 1.3–1.9 times more effective on hCA II comparing with the effectivenes of the compounds on hCA I. 相似文献
90.
David L. Dreyer 《Phytochemistry》1974,13(12):2883-2884