A screening method of oil-soluble synthetic dyes in chilli products based on multi-wavelength chromatographic fingerprints comparison.

A multi-wavelength HPLC fingerprint comparison method was proposed for the screening of oil-soluble synthetic dyes in chilli products. The screening was based on the fingerprint differences of normal unadulterated chilli sample with tested chilli samples. The samples were extracted with acetone and fingerprinted by HPLC under four visible light wavelengths (450 nm, 490 nm, 520 nm, and 620 nm). It was found that the fingerprints of different chilli product samples had a relatively fixed number of peaks and stable retention time. When 16 kinds of known synthetic dyes were used as model analytes to assess the screening efficiency, 14 of them could be screened using fingerprint comparison method, with LOD of 0.40-2.41 mg/kg. The new screening method was simple and had the possibility of finding existence of the adulterated dyes which could not be identified using known standard analytes as control.

Simultaneous determination of 14 oil-soluble synthetic dyes in chilli products by high performance liquid chromatography with a gel permeation chromatography clean-up procedure.

A method was developed for the simultaneous determination of 14 fat-soluble dyes in chilli products. The samples were extracted with hexane/acetone. The cleanup was performed with gel permeation chromatography (GPC) cleanup system. A HPLC separation was performed using variable wavelength detector and a gradient elution with 0.1% formic acid and methanol-acetonitrile (1:1, v/v) as the mobile phases. Good linearity (R² ≥ 0.995) was observed between 0.1 and 5.0 µg/mL. Detection limits of the investigated dyes, which were evaluated at signal to noise ratio of 3, were in the ranges of 11-71 µg/kg. The recoveries of the 14 synthetic colourants in three matrices ranged from 73.4% to 103.5%. Relative standard deviations ranged from 3.7% to 12.3%. The method has been successfully used for the determination of banned dyes in real samples.

Hypoglycemic and hypocholesterolemic effects of Coptis chinensis franch inflorescence.

Hypocholesterolemic and hypoglycemic activities of Coptis chinensis franch inflorescence (Coptis inflorescence) were studied using animal models. Serum total and LDL cholesterol of rats fed a diet containing 1% cholesterol and 0.5% cholic acid increased, as compared with those of rats fed a normal diet. The level of total and LDL cholesterol were reduced markedly in a dose dependent manner, in rats given Coptis inflorescence extract orally at doses of 0.25, 0.5 g/kg.day for 4 weeks. In diabetic rats induced by alloxan, Coptis inflorescence extract showed a significant (p < 0.05) blood sugar lowering activity at all experimented doses (0.125, 0.25 and 0.5 g/kg.day). The highest reduction of blood sugar was about 58% when the rats were given Coptis inflorescence extract orally at a dose of 0.5 g/kg.day for 3 weeks. The 100 g dried water extract of Coptis inflorescence contained 8.11 g total alkaloid, 3.34 g berberin, 1.08 g palmatine and 0.66 g jatrorrhizine, which had long been identified as active compounds in Coptis chinensis franch root (Coptis root). Thus, the results suggest that Coptis inflorescence would be effective in the prevention and management of coronary artery disease by lowering serum cholesterol and blood sugar.