GA3 was identified as a major GA in Neurospora crassa by gas chromatography/selected ion monitoring (GC/SIM) and its content was measured at various stages (0~96 hr after inoculation) of conidial germination and mycelial growth. The GA3 content in the fungus was 190ng/g dry weight at the initial stage and then decreased rapidly; that per liter culture decreased soon after the inoculation, and then increased to 17.6 ng 96 hr after inoculation. The GA3 concentration in the culture medium was around 10?11m throughout the 96-hr incubation. The physiological role of endogenous GA in Neurospora crassa is also discussed. 相似文献
Steviol (ent-13-hydroxykaur-16-en-19-oic acid)* is metabolized by Gibberella fujikuroi in the presence of inhibitors of gibberellin biosynthesis, such as quaternary ammonium salt-type growth retardants, to afford 7β-Miydroxy- and 6β,7β-dihydroxysteviol, gibberelhns A1, A18, A19, A53 and 7β,13-dihydroxykaurenolide. Steviol acetate (ent-13-acetoxykaur-16-en-19-oic acid) is also metabolized to the 6β,7β-dihydroxy-derivative and to the 13-acetyl derivatives of gibberellins A17 and A20 and steviol methyl ester (methyl ent-13-hydroxykaur-16-en-19-oate) into the monohydroxy-, dihydroxy- and hydroxyoxo-derivatives. These results indicate a low substrate specificity of the enzymes in the fungus and provide a useful preparative methodology of several important plant gibberellins carrying the 13-hydroxyl group. 相似文献
The female sex pheromone of the oriental corn borer, Ostrinia furnacalis Guenée, was presumed to be composed of (Z)-12-tetradecenyl acetate and its geometrical isomer using electroantennogram technique. From the extracts of female moths, the presence of these compounds in a ratio of ca. 3:2 was confirmed by gas-liquid chromatography and gas-liquid chromatography combined with mass spectrometry in selected ion monitoring mode. Since the male moths were not attracted to mixtures of the two synthetic compounds, the presence of minor component(s) was suggested. 相似文献
The rice lamina inclination test indicated the presence of brassinosteroid-like active substances in immature Vicia faba seeds. Two of these were identified as castasterone and brassinolide by GC/MS and GC/SIM, respectively. Another active principle was identified as methyl 4- chloroindole-3-acetate by GC/MS and HPLC. 相似文献
The 1C conformation was estimated for α-d-galactopyranosiduronic acid moiety of pectic acid in the permethylated derivative dissolved in 1 n NaOD-D2O and in the peracetylated derivative dissolved in dimethyl sulfoxide-d6, and the C1 conformation was estimated for some derivatives of d-galactopyranuronic acid in chloroform-d by NMR spectroscopy.
Random conformation of the whole macromolecule was estimated for pectic acid in water on the basis of no appearance of any induced Cotton effects in the 200 ~ 700 mμ region in the ORD spectra of pectic acid-anionic dye complexes.
The conformation was supported by the fact that the rate of periodate oxidation of pectic acid at 5° was slightly decreased in comparison with that of amylase in 7 m urea solution.
Oligosaccharides terminated by radioactive sucrose at the reducing end of maltooligosaccharides have been used in the oligosaccharide mapping procedure for characterizing α-amylases. The action patterns of ten α-amylases from various origins were investigated with this mapping method and compared with the results with normal maltooligosaccharides. The experimental results indicated that Bacillus subtilis saccharifying, Endomycopsis and pancreatic α-amylases had similar action patterns toward oligosaccharides with or without fructose at the reducing end. However, the action patterns of other seven α-amylases were somewhat different. 相似文献
Molecular formula C25H37–39NO4 was assigned to Piericidin A. Through the examination of the ultraviolet, infrared and n.m.r. spectra and of chemical evidences, it was shown that Piericidin A contains one secondary alcohol, one acidic hydroxyl group, two methoxyl groups, tri- and tetra-substituted conjugated dienes and one polysubstituted heteroaromatic ring. 相似文献