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An efficient pressurized liquid extraction (PLE) technique was employed in extracting chromones from the roots of Saposhnikovia divaricata (Radix Saposhnikoviae). Chromones were quantified and analyzed by LC-ESI/MS. The PLE procedure was optimized, validated and compared with the other conventional extraction techniques. PLE gained the best result due to the highest extraction efficiency within the shortest extraction time. The optimal conditions of PLE were employing 50% ethanol as the extraction solvent at a temperature of 140°C and an extraction pressure of 1500 psi, using one extraction cycle with a static extraction time of 8 min. A good LC separation was achieved using a Hypersil ODS2 column and methanol/water as the mobile phase at a flow rate of 0.8 mL/min. MS coupling with an ESI interface in the positive ion mode was used as the detection technique. This is the first report on combining PLE with LC-ESI/MS for the extraction and quantification of chromones in Radix Saposhnikoviae. The elaborated PLE method also provided a good alternative for the chromone extraction from other plant substances.

The fresh fruit (Japanese name, Tonburi) of Kochia scoparia has been used as a food garnish in Japanese-style dishes from ancient times, and may prevent metabolic syndromes such as hyperlipidemia, hypertension, obesity and atherosclerosis. This study was performed to clarify whether an ethanol extract of K. scoparia fruit prevented obesity induced in mice by a high-fat diet for 9 weeks. The ethanol extract of K. scoparia fruit prevented the increases in body weight and parametrial adipose tissue weight induced by the high-fat diet. Furthermore, consumption of a high-fat diet containing 1% or 3% K. scoparia extract significantly increased the fecal content and the fecal triacylglycerol level at day 3 compared with those in the high-fat diet group. The ethanol extract (250 mg/kg) and total saponins (100 mg/kg) of K. scoparia inhibited the elevation of the plasma triacylglyccerol level 2 or 3 h after the oral administration of the lipid emulsion. Total saponins, momordin Ic, 2′-O-β-d-glucopyranosyl momordin Ic and 2′-O-β-d-glucopyranosyl momordin IIc isolated from K. scoparia fruit inhibited the pancreatic lipase activity (in vitro). These findings suggest that the anti-obesity actions of K. scoparia extract in mice fed a high-fat diet may be partly mediated through delaying the intestinal absorption of dietary fat by inhibiting pancreatic lipase activity. Copyright © 2006 John Wiley & Sons, Ltd.

In preliminary experiments, polyphenol fractions prepared from the leaves of Salix matsudana reduced the elevation of the rat plasma triacylglycerol level at 3 and 4 h after oral administration of a lipid emulsion containing corn oil, at a dose of 570 mg/kg. The present study examined the anti-obesity action of polyphenol fractions of S. matsudana leaves by testing whether the polyphenol fractions prevented the obesity induced by feeding a high-fat diet to female mice for 9 weeks. Body weights at 2-9 weeks and the fi nal parametrial adipose tissue weights were significantly lower in mice fed the high-fat diet with 5% polyphenols of S. matsudana leaves than in those fed the high-fat diet alone. The polyphenols of S. matsudana leaves also significantly reduced the hepatic total cholesterol content, which was elevated in mice fed the high-fat diet alone. In addition, the polyphenol fractions of S. matsudana leaves inhibited palmitic acid uptake into brush border membrane vesicles prepared from rat jejunum and alpha-amylase activity, and their fractions enhanced norepinephrine-induced lipolysis in fat cells. In conclusion, it is suggested that the inhibitory effects of the flavonoid glycoside fraction of S. matsudana leaves on high-fat diet-induced obesity might be due to the inhibition of carbohydrate and lipid absorption from small intestine through the inhibition of alpha-amylase and palmitic acid uptake into small intestinal brush border membrane or by accelerating fat mobilization through enhancing norepinephrine-induced lipolysis in fat cells.

Previously, it was reported that polyphenol fractions prepared from the leaves of Salix matsudana reduced the elevation of the rat plasma triacylglycerol level at 3 and 4 h after oral administration of a lipid emulsion containing corn oil, at a dose of 570 mg/kg. Moreover, body weights at 2-9 weeks and the fi nal parametrial adipose tissue weights were significantly lower in mice fed the high-fat diet with 5% polyphenol fractions of S. matsudana leaves than in those fed the high-fat diet alone. The polyphenol fractions of S. matsudana leaves also significantly reduced the hepatic total cholesterol content, which was elevated in mice fed the high-fat diet alone. In addition, the polyphenol fractions of S. matsudana leaves inhibited palmitic acid uptake into brush border membrane vesicles prepared from rat jejunum and alpha-amylase activity, and their fractions enhanced norepinephrine-induced lipolysis in fat cells. To clarify the active substances inhibiting the palmitic acid uptake into small intestinal brush border membrane, the alpha-amylase activity or enhancing the norepinephrine-induced lipolyis in fat cells, the isolation of the active substances from polyphenol fraction was attempted using the above three assay systems. Compounds 1, 2 and 3 were isolated from the polyphenol fractions and identified as apigenin-7-O-d-glucoside, luteolin-7-O-d-glucoside and chrysoeriol-7-O-d-glucoside, respectively. Among three flavonoids, apigenin-7-O-d-glucoside inhibited alpha-amylase activity, and luteolin-7-O-d-glucoside and chrysoeriol-7-O-d-glucoside inhibited palmitic acid uptake into small intestinal brush border membrane. Furthermore, three flavonoid glucosides enhanced norepinephrine-induced lipolysis in fat cells.