ABSTRACT
@#To investigate the effect and possible mechanisms of triterpenic acid-enriched fraction from Cyclocarya paliurus(TAE)on glucagon secretion in insulin-resistance pancreatic α cells, the model of insulin resistance in αTC1-6 cells was induced by long term exposure to high glucose. Experimental groups were divided as follow: control(5. 5 mmol/L glucose), model(25 mmol/L), TAE(1, 5, 10 μg/mL), and TAE(10 μg/mL)plus wortmannin(10 nmol/L)group. The supernatant and lysate of treated cells were collected to determine glucagon secretion by ELISA kit. The mRNA and protein abundance of IRS-1, PI3K and Akt were measured by qPCR and Western blot analysis. Results showed that TAE could not only significantly reduce glucagon secretion induce by high glucose in a dose-dependent manner, but also remarkably increased the mRNA and protein abundance of IRS-1, PI3K and Akt in αTC1-6 cells. However, these effects of TAE were reversed by PI3K inhibitor wortmannin. In conclusion, it suggested that TAE could improve the insulin resistance induced by high glucose in pancreatic α cells which may be related with the activation of IRS-1/PI3K/Akt signaling pathway.
ABSTRACT
This study was designed to investigate triterpenoids from the roots of Rosa laevigata Michx. The silica gel column chromatography was used to separate the chemical constituents from the roots of Rosa laevigata Michx. HPLC was used to analyze its purity and chemical constitution. Spectroscopy methods were used to determine their structures. Five constituents were isolated and identified as19α-OH-3β-E-feruloyl corosolic acid (1), 23-hydroxy-tormentic acid (2), 2α, 3β, 19α, 23-tetrahydroxy-12-en-28-oleanolic acid (3), 2α, 3α, 20β-trihydroxyurs-13 (18)-en-28-oic-acid (4), 2α, 3β, 20β-trihydroxyurs-13 (18)-en-28-oic-acid (5). Compound 1 was assigned as a new compound, compounds 4, 5 were obtained from the genus Rosa for the first time.
ABSTRACT
Objective: To develop a method for the simultaneous determination of several triterpenic acids in Jujubae Fructus and provide the technical support for the quality control of Jujubae Fructus. Methods: Betulinic acid was used as the internal reference substance, and the relative correlation factors (RCF) of oleanolic acid, ursolic acid, betulonic acid, oleanonic acid, and ursonic acid were determined by HPLC-ELSD. The contents of the five components were calculated according to the RCF, respectively. The contents of these six triterpene acids in 15 batches of Jujubae Fructus were determined by the external standard method. The rationality, feasibility, and repeatability for the method of quantitative analysis of multi-components by single-marker (QAMS) were verified by comparing with the results obtained from the external standard method. Results: The reproducibility of the RCF was acceptable. For the six triterpene acids, there was no significant difference between the quantitative results with the two different methods in the 15 batches of Jujubae Fructus. Conclusion: The method established in this research is accurate and feasible that it just needs to assay single-marker (betulinic acid) for the determination of six triterpenic acids in Jujubae Fructus simultaneously. Therefore, this method is helpful for the quality control of Jujubae Fructus and could provide a new reference for the quality assess of multi components in Chinese materia medica.
ABSTRACT
Oleanolic acid (OA) and ursolic acid (UA) are isomeric triterpenic acids and only one methyl's position is different between them.OA and UA always exist in the same plant,so it is difficult to separate them when determining contents by RP-HPLC.In this study,a very simple mobile phase for HPLC was developed to simultaneously determine UA and OA,and the factors affecting separation were also discussed.The mobile phase is methanol:water (95∶5) with flow rate 0.4mL/min.The retention time for OA and UA was 20.58 and 21.57 min,respectively,the resolution was 1.61.The average contents of OA and UA of three Loquat leaves sets were 1.4 mg/g and 5.6 mg/g,respectively.Regarding the HPLC,we found that changing mobile phase,adjusting the pH value or adding ion-pairing agent could not affect the separation between UA and OA greatly.While adjustment of the flow rate and column temperature could improve the resolution greatly.
ABSTRACT
Objective To study the chemical constitutents of Fomes officinalis and their inhibiting (effect) on thrombin. Methods Compounds were separated by column chromatography with silica gel and polyamide, whose structures were elucidated by spectral analysis and chemical evidence. Results Seven compounds were isolated from the chloroform extract. Their structures were identified as: 3-keto-dehydrosulfurenic (Ⅰ), dehydroeburicoic acid (Ⅱ), eburicoic acid (Ⅲ), sulphurenic acid (Ⅳ), dehydrosulphurenic acid (Ⅴ), dehydroeburiconic acid (Ⅵ), versisponic acid D (Ⅶ). The inhibitory rate of compound Ⅶ on thrombin was 45.36% but others were not obvious. Conclusion Compounds Ⅴ, Ⅶ are isolated from the fungus for the first time. Compound Ⅶ is effective to anti-thrombin at higher concentration, while the remainders are not obvious.
ABSTRACT
Object To study the chemical constituents from the root of Rubus innominatus S. Moore (Rosaceae). Methods Twelve compounds were isolated from the methanol extract by repeated column chromatography over normal and reversed phase silica gels. Their structures were identified by analysis of their spectral data and comparing TLC with authentic samples. Results Ten triterpenic acids and two steroids were isolated and identified. The antibacterial test indicated some triterpenic acids had antibacterial activity. Conclusion All compounds were obtained from the plants of Rubus L. for the first time.
ABSTRACT
Two isomeric pentacyclic-triterpenic acids were isolated from the root of Ampelosis brevipedunculata var hancei Rhed for the first time. One acid was identified as oleanolic acid by means of physico-chemical properties and spectral analysis. The other one was acetylatcd and confirmed by X-ray diffraction analysis. This acid was proved to be betulinic acid.