ABSTRACT
Objective:To characterize the structure of polysaccharide isolated from Linggui Zhugan Tang（LGZGT）,including monosaccharide composition and functional group detection, investigate the difference of the antioxidant activities of crude polysaccharide（CP） and pure polysaccharide（PP）, and provide the basis for the quality evaluation of LGZGT by in vitro bioassay. Method:The average molecular weight of CP was analyzed by high performance gel chromatography（HPGPC）. Gas chromatography-mass spectrometry（GC-MS） and fourier transform infrared（FT-IR） were employed to determine the structure of the polysaccharide. The antioxidant activities of CP and PP samples were evaluated on the basis of 1-diphenyl-2-picrylhydrazyl（DPPH） radical scavenging activity and OH radical scavenging activity. Result:The total polysaccharide was composed of single peaks, with a molecular weight of 3 689 Da. It was mainly composed of arabinose, mannose, glucose, galactose and fructose with a molar ratio of 6.85∶1.00∶109.21∶1.04∶21.82. Among them，glucose and fructose were the predominant components. In addition， IR study indicated the presence of pyranose and anomeric configurations in glycan structure, with two stereoisomers of glycosidic bond (α-glycosidic bond and β-glycosidic bond). It was found that the total polysaccharide had the ability of scavenging DPPH and hydroxyl radicals, and the activity of crude polysaccharide was better than that of refined polysaccharide. It was found in antioxidant research that the total polysaccharide had the ability of scavenging DPPH and hydroxyl radicals, and the activity of CP was better than that of PP. Furthermore, LC-Q-TOF-MS was used to qualitatively analyze the other components in CP, which indicated that it was related to the adsorption of pentacyclic triterpenoids in Glycyrrhiza uralensis. Conclusion:The polysaccharides and pentacyclic triterpenoids in LGZGT are the material basis for the antioxidative effect of LGZGT. The antioxidative activity determined by in vitro bioassay can be used as an evaluation index for the overall quality control of LGZGT.
ABSTRACT
In order to study the influence of ecological environment regarding the synthesis and accumulation of metabolites in Eucommiae Cortex, LC-QTOF MS/MS method combined with multivariate statistical analysis was used to analyze the differences of chemical constituents in Eucommiae Cortex from different habitats. Through the analysis of the multistage tandem mass spectrometry, the characteristic peaks were extracted with mass spectrometry data peak matching, peak alignment, and noise filtering. Principal component analysis (PCA) and partial least-squares discriminant analysis (PLS-DA) were used for data processing. The chemical constituents were identified or tentative presumed according to MS accurate mass and MS/MS spectrometry fragmentation information, combined with the software of database search, comparison with reference standards and literature. The results show the differences among samples of Eucommiae Cortex from different habitats are distinguishable. A total of 23 chemical constituents in Eucommiae Cortex were identified or tentative presumed. Among of them, 14 kinds of common differential chemical constituents (aucubin, geniposidic acid, neochlorogenic acid, syringin, olivil-4',4'-di-O-β-D-glucopyranoside, chlorogenic acid, cryptochlorogenic acid, 1-hydroxypinoresinol- 4',4'-di-O-β-D-glucopyranoside, caffeic acid, pinoresinol-di-O-β-D-glucopyranoside, syringaresionl-di-O-β-D-glucopyranoside, pinoresinol-4'-O-β-D-glucopyranoside, eucommiol, isochlorogenic acid C and asiatic acid) presented different changing laws. This study provides basic information for revealing the influence law of ecological environment on the biosynthesis of metabolites in Eucommiae Cortex.
ABSTRACT
<p><b>OBJECTIVE</b>To evaluate a microarray-based mutation screening method for genetic deafness and its application in prenatal diagnosis.</p><p><b>METHODS</b>Mutation screening of common deafness genes was performed in pregnant women and volunteers spouses. Nine common mutations in four major deafness genes, GJB2, GJB3, SLC26A4 and mitochondrial 12S rRNA, were detected simultaneously by a microarray-based method. Genetic counseling was given based on their testing results.</p><p><b>RESULTS</b>5.11% of pregnant women carried at least one mutation. Among them, seven carried mutation in the mitochondria 12S rRNA gene and were offered aminoglycoside-induced ototoxicity warning. For other mutation carriers of GJB2 or SLC26A4 genes, additional mutation screening was performed in their husbands by direct sequencing. A total of 20 couples were at risk of giving birth to children with genetic deafness. Of five couples who selected to undergo prenatal diagnostic testing of the fetus, four were diagnosed as wild type or heterozygous for the tested genes and one as p.V37I/c.235delC compound heterozygous for GJB2.</p><p><b>CONCLUSIONS</b>DNA microarray is a quick, easy and reliable method to screen mutations in genetic deafness genes. Application of this method in prenatal screening and diagnosis might effectively reduce the occurrence of genetic deafness.</p>