[Orthogonal Experiment for Optimization of the Sample Pretreatment Conditions for the Serum Cholesterol and Markers Determination by GC-MS].

The objective is to use orthogonal experiment to optimize the pretreatment on the determination of serum cholesterol and its markers by GC-MS. And then the method is evaluated in a methodological perspective. The methodis to Use L16(211) orthogonal experiment design to observe the influence of three key steps，althogether seven factors of pretreatment, which are saponification (KOH ethanol solution concentration, temperature and time), extraction (dose) and derivatization (temperature , time and dose). As for the results，the conditions of optimal pretreatment are as follows：the ethanol solution is 1 mol·L-1 KOH, the saponification temperature is 70 ℃;the saponification time is 60 min;the Solvent quantity is 2 mL;the derivatization temperature is 70 ℃;the derivatization time is 60 min，and the derivatization agent is 100 µL. Through the optimization by orthogonal design and methodological evaluation, the determination of serum cholesterol and its markers by GC-MS is excellent in terms of accuracy and precision, and methodological evaluation indexes are better than those reported in other papers.

Effect of Berberine on promoting the excretion of cholesterol in high-fat diet-induced hyperlipidemic hamsters.

BACKGROUND: Berberine (BBR), as a new medicine for hyperlipidemia, can reduce the blood lipids in patients. Mechanistic studies have shown that BBR activates the extracellular-signal regulated kinase pathway by stabilizing low-density-lipoprotein receptor mRNA. However, aside from inhibiting the intestinal absorption of cholesterol, the effects of BBR on other metabolic pathways of cholesterol have not been reported. This study aimed to investigate the action of BBR on the excretion of cholesterol in high-fat diet-induced hyperlipidemic hamsters. METHODS: Golden hamsters were fed a high-fat diet (HFD) for 6 weeks to induce hyperlipidemia, followed by oral treatment with 50 and 100 mg/kg/day of BBR or 10 and 30 mg/kg/day of lovastatin for 10 days, respectively. The levels of total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), transaminases, and total bile acid in the serum, liver, bile and feces were measured using an enzyme-linked immunosorbent assay. The cholesterol (as well as coprostanol) levels in the liver, bile and feces were determined by gas chromatography-mass spectrometry. RESULTS: The HFD hamsters showed significantly hyperlipidemic characteristics compared with the normal hamsters. Treatment with BBR for 10 days reduced the serum TC, TG and LDL-C levels in HFD hamsters by 44-70, 34-51 and 47-71%, respectively, and this effect was both dose- and time-dependent. Initially, a large amount of cholesterol accumulated in the hyperlipidemic hamster livers. After BBR treatment, reductions in the liver cholesterol were observed by day 3 and became significant by day 7 at both doses (P < 0.001). Meanwhile, bile cholesterol was elevated by day 3 and significantly increased at day 10 (P < 0.001). BBR promoted cholesterol excretion from the liver into the bile in hyperlipidemic hamsters but not in normal hamsters, and these results provide a link between the cholesterol-lowering effect of BBR with cholesterol excretion into the bile. CONCLUSIONS: We conclude that BBR significantly promoted the excretion of cholesterol from the liver to the bile in hyperlipidemic hamsters, which led to large decreases in the serum TC, TG and LDL-C levels. Additionally, compared with lovastatin, the BBR treatment produced no obvious side effects on the liver function.

Identification of the anti-oxidants in Flos Chrysanthemi by HPLC-DAD-ESI/MS(n) and HPLC coupled with a post-column derivatisation system.

INTRODUCTION: Flos Chrysanthemi (Jiju) is a traditional Chinese medicine (TCM) that is known to have anti-oxidant activity; in this study, on-line HPLC-DAD-ESI/MS(n) and HPLC-DAD-DPPH methods have been developed for rapidly screening and identifying free-radical scavengers in Jiju extract. OBJECTIVE: To develop an efficient method for the simultaneous identification and detection of the anti-oxidant components in Flos Chrysanthemi (Jiju). METHODOLOGY: A concentrated methanol extract of Flos Chrysanthemi from Jiaxiang County (Jiju) was first separated into phases soluble in water, petroleum ether and n-butanol. The off-line 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging method was then used to evaluate the anti-oxidant activity of each phase in vitro. The results showed that the n-butanol extract had the highest anti-oxidant activity, and its anti-oxidant compounds were analysed by HPLC-DAD-ESI/MS(n) and HPLC coupled with a post-column derivatisation (PCD) system supplied with DPPH, aluminium chloride or sodium acetate solutions. RESULTS: A total of 17 compounds were separated and identified, three of which were identified in Jiju for the first time, and seven active compounds serve as the chemical basis of the anti-oxidant efficacy of Jiju. CONCLUSION: The methods described here allow rapid separation and convenient identification of the multiple constituents in Jiju, and may be applied to other complex natural matrices.