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351.
352.
Conversion of zearalenone to zearalenone glycoside by Rhizopus sp   总被引:2,自引:0,他引:2  
The microbial conversion of zearalenone by various species of fungi was studied. Among them, Rhizopus sp. was the sole fungus which produced a new metabolite from zearalenone in addition to alpha- and beta-zearalenol. The structure of the new metabolite was determined to be zearalenone 4-beta-D-glucopyranoside on the basis of mass, infrared, and nuclear magnetic resonance spectroscopies. The results suggest that the mycelium of Rhizopus sp. catalyzes the glycosidation at the C-4 position of zearalenone.  相似文献   
353.
Two methods have been developed for the simultaneous determination of griseofulvin and its major metabolite 6-desmethylgriseofulvin in plasma using electron-capture gas chromatography. The first method was based on the quantitative reversion of the 6-desmethyl metabolite to griseofulvin by diazomethane. Plasma extract was chromatographed both before and after treatment with diazomethane, the former being the measure of griseofulvin and the latter representing the sum of the two compounds. In the second method, plasma extract was treated with diazobutane and griseofulvin and the butylated metabolite were separated by gas chromatography. The sensitivity for griseofulvin was 20 ng/ml by both methods and that for the metabolite was 20 ng/ml and 40 ng/ml by the first and the second method, respectively. The concentrations of the metabolite as well as griseofulvin were determined in dog and human plasma after oral administration of griseofulvin.  相似文献   
354.
The evolution of a female penis is an extremely rare event and is only known to have occurred in a tribe of small cave insects, Sensitibillini (Psocodea: Trogiomorpha: Prionoglarididae). The female penis, which is protrudable and inserted into the male vagina‐like cavity during copulation to receive semen, is thought to have evolved independently twice in this tribe, in the Brazilian Neotrogla and the African Afrotrogla. These findings strongly suggest that there are some factors unique to Sensitibillini that have facilitated female penis evolution. Here, several hypothetical factors are presented that may have enabled the evolution of the female penis in Sensitibillini. The female–female competition for nutritious semen, the oligotrophic environment, and the twin insemination slots with switching valve are considered to be the driving factors for female penis evolution. Additionally, the following factors are considered responsible for relaxing the constraint against female penis evolution: preexistence of the female‐above mating position, the elongated duct connecting the female pre‐penis with the sperm storage organ, and the small male genital cavity accepting the female genital tubercle bearing the opening of this duct. Understanding the factors enabling female penis evolution may also shed light on the evolution of the male penis.  相似文献   
355.
Journal of Industrial Microbiology & Biotechnology - Microbial production of cis,cis-muconate (ccMA) from phenolic compounds obtained by chemical depolymerization of lignin is a promising...  相似文献   
356.
357.
In other to examine the binding ability of the 5'-terminal part of eukaryotic mRNA to 80S ribosome, several kinds of oligoribonucleotides, pA-U-G, m7G5'pppA-U-G, m7G5'pppG-U, m7G5'pppA-U-G-A-C-C, were synthesized chemically. The binding experiments of oligonucleotides to 80S ribosome showed that the capped structure as well as AUG are essential for ribosome binding, and the efficiency is enhanced by the 5'-leader sequence if it would include complementary sequence to the 3'-terminal part of 18S rRNA.  相似文献   
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