Rapid determination of paeoniflorin from Paeonia sinjiang K. Y. Pan. by rapid resolution liquid chromatography
A rapid, effective, binary reverse phase rapid resolution liquid chromatographic method has been developed for the determination of Paeoniflorin extracted from Paeonia sinjiang K. Y. Pan. with short run time. RRLC separation was achieved by using Agilent (Zorbas XDB-C18 4.6 mm × 50 mm, 1.8 μm) column with mobile phase complosed of methanol and 0.05 mol/l potassium phosphate monobasic. Flow rate was at 1.0 ml/min. Retention time was at about 1.16 min. Recovery rate was 99.8% and relative standard deviation of three replicate samples tested was 1.8%. RRLC method has been applied to both in vitro studies of paeoniflorin formulation and drug estimation in biological samples.
[Quality evaluation of prepared slices of Paeonia lactiflon--determination of paeoniflorin by HPLC].
OBJECTIVE
To establish the quality criteria of the prepared slices of Paeonia lactiflon.


METHOD
RP-HPLC was used for the determination of paeoniflorin in 10 lots of samples by ultrasound-assisted extraction.


RESULT
The samples were extracted with 50% methanol. Seperation of the solution was performed on an ODS column with a mobile phase of acetonitrile-water (18:82), detected at 230 nm.


CONCLUSION
The method is simple, repeatable, accurate and applicable.
Effect of a new inhibitor of cholesterol biosynthesis (AY 9944) on serum and tissue sterols in the rat.
AY 9944 is a novel inhibitor of cholesterol biosynthesis which appears to act on the Delta 7-reductase enzyme, interfering with the conversion of 7-dehydrocholesterol to cholesterol. In all tissues studied, with the exception of the lens, there was a reduction in cholesterol and a marked accumulation of 7-dehydrocholesterol. Isotope studies showed a reduced uptake of acetate into cholesterol, and an increased uptake into 7-dehydrocholesterol, in various tissues in vivo and by skin samples in vitro. There was no apparent accumulation of lanosterol or of the methostenols in the rat skin.