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1.
2.
Microbial transformation of zaluzanin-D   总被引:2,自引:0,他引:2  
Microbial transformation of zaluzanin-D using different fungi gave 11,13-dihydrozaluzanin-C, zaluzanin-C, 4,16,11,13 - tetrahydro zaluzanin-C, estafiatone, dihydroestafiatol and dihydroestafiatone.  相似文献   

3.
The microbial transformation of mesterolone (= (1alpha,5alpha,17beta)-17-hydroxy-1-methylandrostan-3-one; 1), by a number of fungi yielded (1alpha,5alpha)-1-methylandrostane-3,17-dione (2), (1alpha,3beta,5alpha,17beta)-1-methylandrostane-3,17-diol (3), (5alpha)-1-methylandrost-1-ene-3,17-dione (4), (1alpha,5alpha,15alpha)-15-hydroxy-1-methylandrostane-3,17-dione (5), (1alpha,5alpha,6alpha,17beta)-6,17-dihydroxy-1-methylandrostan-3-one (6), (1alpha,5alpha,7alpha,17beta)-7,17-dihydroxy-1-methylandrostan-3-one (7), (1alpha,5alpha,11alpha,17beta)-11,17-dihydroxy-1-methylandrostan-3-one (8), (1alpha,5alpha,15alpha, 17beta)15,17-dihydroxy-1-methylandrostan-3-one (9), and (5alpha,15alpha,17beta)-15,17-dihydroxy-1-methylandrost-1-en-3-one (10). Metabolites 5-10 were found to be new compounds. All metabolites, except 2, 3, 6, and 7, exhibited potent anti-inflammatory activity. The structures of these metabolites were characterized on the basis of spectroscopic studies, and the structure of 5 was also determined by single-crystal X-ray-diffraction analysis.  相似文献   

4.
El Sayed KA 《Phytochemistry》2000,53(6):675-678
Preparative-scale fermentation of papaveraldine (1), the known benzylisoquinoline alkaloid, with Mucor ramannianus 1839 (sih) has resulted in a stereoselective reduction of the ketone group and the isolation of S-papaverinol (2) and S-papaverinol N-oxide (3). The structure elucidation of both metabolites was based primarily on 1D-, 2D-NMR analyses and chemical transformations. The absolute configuration of 2 was determined using Horeau's method of asymmetric esterification. These metabolism results were consistent with the previous plant cell transformation studies on papaverine and isopapaverine.  相似文献   

5.
При помощи ?ерменентации со 191 штаммом 94 видов рода Penicillium исследовались превращения прогестерона. Качественный анализ метаболитов при помощи хроматогра?ии на бумаге с различной детекцией при сравнении со стандартными образцами обнаружил З основных типа превращений, а именно, отщепление боковой цепи прогестерона на С17 при образовании. с другой сторны, тестололактона, а с другой стороны, тестостерона в качечестве конечного метаболита и гидроксилирование лрогестерона в положении 11, а также в положении 15 стероидного скелета. У некоторых видов рода Penicillium была установлена неспособность превращать молекулу прогестерона в другое стероидное соединение. Отдельные виды Penicillium были разделены на 5 групп по способности их ?ерментных систем вызывать превращения стероидной молекулы прогестерона.  相似文献   

6.
Microbial transformation of xanthohumol   总被引:1,自引:0,他引:1  
Microbial transformation of xanthohumol using the culture broth of Pichia membranifaciens afforded three metabolites, (E)-2"-(2"'-hydroxyisopropyl)-dihydrofurano[2",3":4',3']-2', 4-dihydroxy-6'-methoxychalcone, (2S)-2"-(2"'-hydroxyisopropyl)-dihydrofurano[2",3":7,8]-4'-hydroxy-5-methoxyflavanone and (E)-2"-(2"'-hydroxyisopropyl)-dihydrofurano[2",3":2',3']-4'-hydroxy-5-methoxychalcone.  相似文献   

7.
Summary We tested 163 strains of fungi and bacteria for their ability to (–)-1-(3R, 4R)-tetrahydrocannabinol (= 1-THC) in vivo. In the experiments 51 strains were found to be active and were further tested under varying conditions. The screening is described and the metabolites of 1-THC obtained from the incubations are characterized by their two-dimensional thin-layer Rf values and the color of the azo dyes formed by reacting the cannabinoids with Fast Blue B Salt reagent on the thin-layer plates. Cell-free systems were prepared from four strains of fungi and tested for in vitro conversion of 1-THC. In two of these systems conversion of 1-THC to metabolites could be demonstrated.Part 1, see Binder (1976)  相似文献   

8.
Pyridine and its derivatives have been found as pollutants in the environment. Although alkylpyridines constitute the largest class of pyridines contaminating the environment, little information is available concerning the fate and transformation of these compounds. In this investigation ethylpyridines have been used as model compounds for investigating the biodegradability of alkylpyridines. A mixed culture of ethylpyridine-degrading microorganisms was obtained from a soil that had been exposed to a variety of pyridine derivatives for several decades. The enrichment culture was able to degrade 2-, 3-, and 4-ethylpyridine (100 mg/L) at 28° C and pH 7 within two weeks under aerobic conditions. The degradation rate was greatest for 2-ethylpyridine and least for 3-ethylpyridine. Transformation of ethylpyridines was dependent on substrate concentration, pH, and incubation temperature. Studies on the metabolic pathway of 4-ethylpyridine revealed two products; these chemicals were identified by MS and NMR analyses as 4-ethyl-2(1H)-pyridone and 4-ethyl-2-piperidone. 6-Ethyl-2(1H)-pyridone was determined to be a product of 2-ethylpyridine degradation. These results indicate that the transformation mechanism of ethylpyridines involves hydroxylation and reduction of the aromatic ring before ring cleavage.  相似文献   

9.
Summary Arthrobacter simplex, Serratia marcescens, Fusarium and Mycobacterium were tested for their ability to transform phytosterol to Androsta 1, 4 diene 3, 17 dione (ADD). Arthrobacter simplex ATCC 6946 was found to be more efficient than the other species tested.  相似文献   

10.
A systematic study of transformation reactions of Actinomycetes with respect to the progesterone molecule was undertaken. The results obtained, i.e. the types of transformation reactions in different actinomycete species, were evaluated from the point of view of taxonomy. The actinomycetes tested were divided according to the transformation types into three groups: (1) a group of species transforming progesterone in the 16α-position; (2) a group of species transforming progesterone in the β-position; (3) a group of species in which no capacity to transform progesterone into another steroid derivative was established. From the point of view of Actinomycete classification the transformation reactions on the steroid molecule fulfil all the requirements of taxonomic features of Actinomycetes. They appear to be specific properties, independent of strictly cultivation conditions and common to all the strains of individual actinomycete species tested.  相似文献   

11.
It has been shown that resting cells of Agrobacterium radiobacter catalyze a sequence of two stereospecific hydrolytic reactions leading to the complete transformation of racemic hydantoins to D -amino acids. This report describes some properties of this new biocatalyst and its potential application for the production of some D -amino acids, which are used as intermediates in the preparation of semisynthetic penicillin and cephalosporins.  相似文献   

12.
Summary Abietic acid was quantitatively converted into methyl abietate in a shaken culture of Mycobacterium MB 3683 within 144 hours at the concentration of 200 mg/l.  相似文献   

13.
When studying the transformation reactions of Δ4-3-ketosteroids of the pregnane series by strains ofStreptomyces fradiae, 6β-hydroxy-or 6β, 11α-dihydroxy-derivatives were found to be the main metabolites. From the aspect of the taxonomy of Actinomycetes, these reactions can be utilized in classification of the species, since study of different strains ofStreptomyces fradiae showed that this property is stable and that it is characteristic for the given species.  相似文献   

14.
Microbial transformation of alkaloids   总被引:6,自引:0,他引:6  
Alkaloids continue to provide mankind with a plethora of medicines, poisons and potions. Because many valuable drugs are derived from such natural compounds, there is much interest in their transformation to provide new compounds or intermediates for the synthesis of new or improved drugs. This review aims to provide a survey of alkaloid transformations, and concerns microbial transformations and microbially expressed recombinant plant enzymes and their biotechnological applications.  相似文献   

15.
Differential cryoprotection is afforded to chloroplast thylakoids against freeze-induced uncoupling of cyclic photophosphorylation by equimolar concentrations of glucose, sucrose, and raffinose. This differential protective effect appears to be due to nonideal activity-concentration profiles exhibited by the sugars during freezing. When cryoprotection is analyzed as a function of the mole fraction of NaCl to which the membranes are exposed during freezing, the pattern of protection to cyclic photophosphorylation and its component reactions is not dependent upon the chemical identity of the protective solute. Cryoprotective efficiency of glucose, sucrose, and raffinose can be accounted for by proposing an activity dependent alteration in the freezing environment rather than specific solute-membrane interactions.  相似文献   

16.
As a result of microbial transformation of baicalin and baicalein the products of 4′-hydroxylation of the B ring, O-methylation at C-6, and both O-methylation at C-6 and hydroxylation at C-4′ were obtained. Transformations of baicalin were accompanied by the reaction of hydrolysis.  相似文献   

17.
Candida magnoliae and its mutants were analyzed to produce erythritol from glucose with high yield and productivity. One mutant, M2, showed higher erythritol conversion yield and productivity than the wild strain. The osmophilic mutant produced 25 g erythritol l–1 after 83 h of a flask culture in a medium containing 10% (w/v) glucose, corresponding to a 25% increase in erythritol and a 30% increase in erythritol productivity compared with the wild type. The fermentation properties were further improved by cultivating the osmophilic mutant in a fermenter containing 20% (w/v) glucose medium with 0.54 g l–1 h–1 of erythritol productivity and 43% of erythritol conversion yield based on glucose.  相似文献   

18.
Microbial transformation of zearalenone to a zearalenone sulfate.   总被引:2,自引:0,他引:2       下载免费PDF全文
The conversion of zearalenone by various microorganisms was studied. A new polar metabolite was formed in addition to alpha- and beta-zearalenols. The structure of the new metabolite was determined as zearalenone-4-O-sulfate conjugate on the basis of enzymatic and acid hydrolysis, followed by mass spectrometry, nuclear magnetic resonance, and infrared spectroscopic analysis. The results obtained demonstrate that Rhizopus arrhizus catalyzes sulfation of zearalenone at the C-4 hydroxyl group.  相似文献   

19.
The conversion of zearalenone by various microorganisms was studied. A new polar metabolite was formed in addition to alpha- and beta-zearalenols. The structure of the new metabolite was determined as zearalenone-4-O-sulfate conjugate on the basis of enzymatic and acid hydrolysis, followed by mass spectrometry, nuclear magnetic resonance, and infrared spectroscopic analysis. The results obtained demonstrate that Rhizopus arrhizus catalyzes sulfation of zearalenone at the C-4 hydroxyl group.  相似文献   

20.
Summary 3-Desoxymorphinanes should be transformed by microbial hydroxylation of the aromatic ring to morphinanes. Instead of this reaction the investigated N-derivatives (H, CH3, COCH2OH and COCH2OCH2CH3) are reduced by several fungi to the 6-(R)-hydroxy structures. Rhizopus achlamydosporus cleaved additionally the ethoxy-acetyl-group to a hydroxy-acetate.  相似文献   

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