排序方式: 共有19条查询结果,搜索用时 15 毫秒
1.
2.
Faramarzi MA Tabatabaei Yazdi M Amini M Zarrini G Shafiee A 《FEMS microbiology letters》2003,222(2):183-186
Microbial hydroxylation of progesterone occurred in the culture of Acremonium strictum PTCC 5282 to produce two hydroxylated pregnene-like steroids. The metabolites were purified and characterized using spectroscopic methods and identified as 15alpha-hydroxyprogesterone and 15alpha-hydroxydeoxycorticosterone. 相似文献
3.
Mojtaba Tabatabaei Yazdi Gholamreza Zarrini Elham Mohit Mohammad Ali Faramarzi Neda Setayesh Navid Sedighi Farzaneh Aziz Mohseni 《World journal of microbiology & biotechnology》2006,22(4):325-330
Summary One hundred and sixty-five strains of microorganisms with the ability to grow in a medium containing uric acid as a major
source of nitrogen were isolated from soil samples during a screening program. Among them, a zygomycete fungus with well-developed
columellae was recognized to produce high levels of the enzyme in a short time. Classification of the isolated fungus was
carried out according to the morphological and culture characteristics of the organism, and it was identified as Mucor hiemalis. The fungus was able to produce an intracellular urate oxidase in a fermentation medium mainly containing uric acid. Optimized
composition of the medium consisted of (l−1 of distilled water) uric acid, 7.0 g; maltose, 6.0 g; Vogel stock solution, 20 and 1 ml of 0.5 M copper sulphate. The optimum
pH and temperature for uricase production in the optimized medium were pH 6 and 30 °C, respectively. 相似文献
4.
The ability of a genus of cephalosporium-like fungus isolated from soil, Acremonium strictum PTCC 5282, for hydrocortisone biotransformation has been investigated. This potential had not been previously examined. The fermentation yielded 11beta,17beta-dihydroxyandrost-4-en-3-one, 11beta,17alpha,20beta,21-tetrahydroxypregn-4-en-3-one and 21-acetoxy-11beta,17alpha,20-trihydroxypregn-4-en-3-one. Each microbial metabolite was purified and characterized using spectroscopic methods. 相似文献
5.
Mahsa Moshfegh Ahmad Reza Shahverdi Gholamreza Zarrini Mohammad Ali Faramarzi 《Extremophiles : life under extreme conditions》2013,17(4):677-687
An extracellular haloalkaliphilic thermostable α-amylase producing archaeon was isolated from the saltwater Lake Urmia and identified as Halorubrum xinjiangense on the basis of morphological, biochemical, and molecular properties. The enzyme was purified to an electrophoretically homogenous state by 80 % cold ethanol precipitation, followed by affinity chromatography. The concentrated pure amylase was eluted as a single peak on fast protein liquid chromatography. The molecular mass of the purified enzyme was about 60 kDa, with a pI value of 4.5. Maximum amylase activity was at 4 M NaCl or 4.5 M KCl, 70 °C, and pH 8.5. The K m and V max of the enzyme were determined as 3.8 mg ml?1 and 12.4 U mg?1, respectively. The pure amylase was stable in the presence of SDS, detergents, and organic solvents. In addition, the enzyme (20 U) hydrolyzed 69 % of the wheat starch after a 2-h incubation at 70 °C in an aqueous/hexadecane two-phase system. 相似文献
6.
Coumarins are a well-known group of natural products distributed in the plant kingdom especially in the family Apiaceae with various biological activities. Isoarnottinin 4'-glucoside is a simple glycosylated coumarin found previously in a few genera of Apiaceae, and its biological activities have not been previously described in details. In the present paper, the compound was isolated from Prangos uloptera (Apiaceae) leaves using HPLC techniques. Antimicrobial, phytotoxic and cytotoxic activities of the compound were evaluated by disk diffusion, lettuce assay and MTT method. Our results indicated that the compound has high antibacterial effect against Erwinia carotovora, a common plant pathogen with MIC value of 100 microg/mL. The compound also exhibited significant phytotoxic activity against lettuce and modest cytotoxic activity against HeLa cell line with IC50 of 0 .84 mg/mL. It could be concluded that isoamottinin 4'-glucoside may play phytoalexin or allelopathic role for plant and may be a candidate for an antibacterial agent or a bioherbicide. 相似文献
7.
Furanocoumarins are well-known natural products that occur in the most evolved genera of Apiaceae family. This compounds were
found to have cytotoxic, phytotoxic, photosensitizing, insecticidal, antibacterial and high antifungal effects. Aviprin is
considered as a linear furanocoumarin substituted at C8 with an oxygenated prenyl residue. In this study we found that aviprin
is a bioactive compound that exhibits high antibacterial, antifungal and phytotoxic activity. The compound stunted the germination
of lettuce seeds with IC50 value of 0.270 mg/ml. The compound also inhibited the mycelia growth of Sclerotinia sclerotiorum. Aviprin indicated antibacterial activity against tested gram negative and positive bacteria with inhibition zone of 19–23.5
mm. Our results shown that aviprin can play an allelopatic role for plant. 相似文献
8.
Abdollah Ghasemian Mojtaba Tabatabaei Yazdi Zargham Sepehrizadeh Zohreh Tabatabaei Yazdi Gholamreza Zarrini 《World journal of microbiology & biotechnology》2009,25(5):773-779
A 1.6 kb gene encoding a cholesterol oxidase (choR) from a local isolate, Rhodococcus sp. PTCC 1633 was cloned into pET23a and the highly expressed recombinant enzyme was purified from the cell lysate of IPTG-induced
Escherichia coli BL21(DE3)pLysS with one-step absorption on cholesterol. The purified protein had a molecular mass of 55 kDa, isoelectric
point at about pH 9.0 and absorption peaks at 280, 380 and 460 nm, indicating that the enzyme is a flavoprotein. The optimum
pH and temperature for the recombinant enzyme were 7.0 and 50°C, respectively. Steady-state kinetic revealed that the cholesterol
oxidase had a K
m
of 32 μM. This study is the first report concerning expression and one-step purification of a gene encoding cholesterol oxidase
from Rhodococcus spp. This study revealed that this enzyme is a type II cholesterol oxidase. 相似文献
9.
Mohammad Ali Faramarzi Mojtaba Tabatabaei Yazdi Mohsen Amini Farzaneh Aziz Mohseni Gholamreza Zarrini Amir Amani Abbas Shafiee 《World journal of microbiology & biotechnology》2004,20(7):657-660
Two metabolites were obtained by microbial transformation of androstendione in the culture of Aspergillus terreus PTCC 5283, a fungus isolated from soil. Their structures were established as testosterone and testololactone on the basis of the spectral data including 1H NMR, 13C NMR, FTIR, MS and physical constants such as melting point and optical rotation. Aspergillus terreusproduced both metabolites after 3 days incubation at 27 °C. The bioconversion reactions observed were 17-carbonyl reduction and biological Baeyer–Villiger oxidation. 相似文献
10.
Fakhimi A Iranshahi M Emami SA Amin-Ar-Ramimeh E Zarrini G Shahverdi AR 《Zeitschrift für Naturforschung. C, Journal of biosciences》2006,61(9-10):769-772
In this study the enhancement effect of Sophora pachycarpa roots' acetone extract on the antibacterial activity of gentamycin was evaluated against Staphylococcus aureus. Disc diffusion and broth dilution methods were used to determine the antibacterial activity of gentamycin in the absence and presence of plant extract and its various fractions separated by TLC. A clinical isolate of S. aureus was used as test strain. The active component of the plant extract involved in enhancement of gentamycin's activity had Rf = 0.72 on a TLC plate. The spectral data (1H NMR, 13C NMR) of this compound revealed that this compound was 5,7,2',4'-tetrahydroxy-8-lavandulylflavanone (sophoraflavanone G), previously isolated from Sophora exigua. In the presence of 0.03 microg/ mL of sophoraflavanone G the MIC value of gentamycin for S. aureus decreased from 32 to 8 microg/mL (a four-fold decrease). These results signify that the ultra-low concentration of sophoraflavanone G potentiates the antimicrobial action of gentamycin suggesting a possible utilization of this compound in combination therapy against Staphylococcus aureus. 相似文献