Microbial transformation of the sesquiterpenoid (-)-maalioxide by Mucor plumbeus

Microbial transformation of the sesquiterpenoid (-)-maalioxide by the fungus Mucor plumbeus gave three metabolites, 9beta-hydroxymaalioxide, 1beta-hydroxymaalioxide and 7beta-hydroxymaalioxide. 9beta-hydroxymaalioxide and its structure was established on the basis of its spectroscopic properties and chemical reactions.     

Microbial transformation of (-)-isolongifolol and butyrylcholinesterase inhibitory activity of transformed products

The microbial transformation of (-)-isolongifolol (1) by using the standard two-stage fermentation technique with Fusarium lini afforded polar oxygenated metabolites: 10-oxoisolongifolol (2), 10alpha-hydroxyisolongifolol (3), and 9alpha-hydroxyisolongifolol (4). Metabolites 3 and 4 were also formed with the incubation of 1 with Aspergillus niger. All three metabolites were found to be new. Compounds 3 and 4 inhibited butyrylcholinesterase enzyme in a concentration-dependent manner with IC50 values 13.6 and 299.5 microM, respectively. Compound 3 showed un-competitive mode of inhibition against butyrylcholinesterase with Ki value 15.0 microM. The structures of metabolites 2-4 were deduced on the basis of spectroscopic techniques and single-crystal X-ray diffraction techniques.     

Microbial transformation of delta 9(15)-africanene

Incubation of delta 9(15)-africanene with fungi Aspergillus niger and Rhizopus oryzae for 8 days yielded two oxidized derivatives, 10 alpha-hydroxy-delta 9(15)-africanene and 9 alpha,15-epoxyafricanane. The structure of the two products were assigned by interpretation of their spectral data.     

Influence of the chirality of (R)-(-)- and (S)-(+)-carvone in the central nervous system: a comparative study

Many terpenes are used therapeutically, and as flavor and fragrance materials. (R)-(-)-Carvone, the main constituent of spearmint oil, and (S)-(+)-carvone, found as major component of caraway and dill seed oils, have several applications and are used in cosmetic, food, and pharmaceutical preparations. In this study, the effect of enantiomers of carvone on the central nervous system (CNS) was evaluated in mice. The LD50 value was 484.2 mg/kg (358.9-653.2) for (S)-(+)-carvone, and 426.6 (389.0-478.6) mg/kg for (R)-(-)-carvone. Both enantiomers caused depressant effects, such as decrease in the response to the touch and ambulation, increase in sedation, palpebral ptosis, and antinociceptive effects. (S)-(+)- and (R)-(-)-carvone caused a significant decrease in ambulation. (R)-(-)-Carvone appeared to be more effective than its corresponding enantiomer at 0.5 and 2.0 h after administration. However, (S)-(+)-carvone was slightly more potent at 1 h. In potentiating pentobarbital sleeping time, (R)-(-)-carvone was more effective than (S)-(+)-carvone at 100 mg/kg, but was less potent at 200 mg/kg compared to the (+)-enantiomer, indicating a sedative action. (S)-(+)-Carvone at the dose of 200 mg/kg increased significantly the latency of convulsions induced by PTZ and PIC, but (R)-(-)-carvone was not effective against these convulsions. These results suggest that (S)-(+)-carvone and (R)-(-)-carvone have depressant effect in the CNS. (S)-(+)-Carvone appears to have anticonvulsant-like activity.     

Microbial transformation of neoandrographolide by Mucor spinosus (AS 3.2450)

Microbial transformation of neoandrographolide (1), was performed by Mucor spinosus (AS 3.2450). Ten metabolites were obtained and identified as 14-deoxyandrographolide (2), 17,19-dihydroxy-8,13-ent-labdadien-16,15-olide (3), 3,14-dideoxyandrographolide (4), 7β-hydroxy-3,14-dideoxyandrographolide (5), 17,19-dihydroxy-7,13-ent-labdadien-16,15-olide (6), 8(17),13-ent-labdadien-16,15-olid-19-oic acid (7), 8α,17β-epoxy-3,14-dideoxyandrographolide (8), 8β,17,19-trihydroxy-ent-labd-13-en-16, 15-olide (9), phlogantholide-A (10), 19-[(β-d-glucopyranosyl)oxy]-19-oxo-ent-labda-8(17),13-dien-16,15-olide (11) by spectroscopic and chemical means. Among them, products 3, 5, 6, 8 and 9 were characterized as new compounds. The inhibitory effects of compounds 1–11 on nitric oxide production in lipopolysaccharide-activated macrophages were evaluated and their preliminary structure–activity relationships (SAR) were discussed.     

Microbial transformation of deoxynivalenol (vomitoxin).

Microbial inocula from rumen fluid, soil, and contents of the large intestines of chickens (CLIC) and of swine (SLIC) were tested for their ability to transform deoxynivalenol (vomitoxin) in vitro. Microorganisms in (CLIC) completely transformed pure vomitoxin, and this activity was retained through six serial subcultures. No alteration of the toxin by incubation with SLIC was detected, whereas 35% of the vomitoxin was metabolized in the original culture of rumen fluid and 50% was metabolized by the soil sample, though metabolism was decreased in subsequent subcultures of either sample. A single metabolite was isolated and identified as deepoxy vomitoxin. The increase in concentration of deepoxy vomitoxin in the culture medium corresponded with the decrease in vomitoxin concentration. The vomitoxin transformation rate was not affected by either the ratio of CLIC to vomitoxin (5 to 0.2 g of CLIC per mg of vomitoxin) or the initial concentration of vomitoxin (14 to 1,400 ppm) in the medium. Biotransformation of vomitoxin was completely inhibited when the pH in the medium was lowered to 5.20. Sodium azide at a 0.1% (wt/vol) concentration in the medium blocked the transformation of vomitoxin, suggesting that the deepoxidation of vomitoxin is an energy-dependent process. About 50% of the vomitoxin in moldy corn in culture medium was transformed by microorganisms from CLIC. The vomitoxin transformation rate in moldy corn was not affected when the concentration of CLIC changed from 0.2 to 0.8 g/ml of medium. Vomitoxin in the moldy corn was not transformed when CLIC were added to corn without culture medium.(ABSTRACT TRUNCATED AT 250 WORDS)     

Microbial transformation of deoxynivalenol (vomitoxin).

Microbial inocula from rumen fluid, soil, and contents of the large intestines of chickens (CLIC) and of swine (SLIC) were tested for their ability to transform deoxynivalenol (vomitoxin) in vitro. Microorganisms in (CLIC) completely transformed pure vomitoxin, and this activity was retained through six serial subcultures. No alteration of the toxin by incubation with SLIC was detected, whereas 35% of the vomitoxin was metabolized in the original culture of rumen fluid and 50% was metabolized by the soil sample, though metabolism was decreased in subsequent subcultures of either sample. A single metabolite was isolated and identified as deepoxy vomitoxin. The increase in concentration of deepoxy vomitoxin in the culture medium corresponded with the decrease in vomitoxin concentration. The vomitoxin transformation rate was not affected by either the ratio of CLIC to vomitoxin (5 to 0.2 g of CLIC per mg of vomitoxin) or the initial concentration of vomitoxin (14 to 1,400 ppm) in the medium. Biotransformation of vomitoxin was completely inhibited when the pH in the medium was lowered to 5.20. Sodium azide at a 0.1% (wt/vol) concentration in the medium blocked the transformation of vomitoxin, suggesting that the deepoxidation of vomitoxin is an energy-dependent process. About 50% of the vomitoxin in moldy corn in culture medium was transformed by microorganisms from CLIC. The vomitoxin transformation rate in moldy corn was not affected when the concentration of CLIC changed from 0.2 to 0.8 g/ml of medium. Vomitoxin in the moldy corn was not transformed when CLIC were added to corn without culture medium.(ABSTRACT TRUNCATED AT 250 WORDS)     

Microbial transformation of xanthohumol

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.     

Microbial transformation of cannabinoids

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)     

Microbial transformation of steroids

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.     

Microbial transformation of mesterolone

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.     

Microbial transformation of papaveraldine

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.     

Microbial transformation of zaluzanin-D

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.     

Microbial transformation of ethylpyridines

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.     

Microbial transformation of sterols

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.     

Microbial transformation of steroids

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.     

Microbial transformation of steroid

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.     

Microbial transformation of alkaloids

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.