Pouteria ramiflora extract inhibits salivary amylolytic activity and decreases glycemic level in mice.

In this study, extracts of plant species from the Cerrado biome were assessed in order to find potential inhibitors of human salivary alpha-amylase. The plants were collected and extracts were obtained from leaves, bark, and roots. We performed a preliminary phytochemical analysis and a screening for salivar alpha-amylase inhibitory activity. Only three botanical families (Sapotaceae, Sapindaceae and Flacourtiaceae) and 16 extracts showed a substantial inhibition (>75%) of alpha-amylase. The ethanolic extracts of Pouteria ramiflora obtained from stem barks and root barks decreased amylolytic activity above 95% at a final concentration of 20 µg/mL. Thus, adult male Swiss mice were treated orally with P. ramiflora in acute toxicity and glycemic control studies. Daily administration with 25, 50 and 100 mg/kg of aqueous extract of P. ramiflora for eight days can reduce significantly body weight and blood glucose level in mice. These data suggest that the crude polar extract of P. ramiflora decreases salivary amylolytic activity while lowering the blood levels of glucose.

Determination of short-chain fatty acids in dietary fiber extracts using ion-exclusion chromatography with suppressed conductivity detection.

A new chromatographic method for the sequential determination of short-chain fatty acids is described. Acetic, propionic and butyric acids were determined in dietary fiber extracts using ion-exclusion chromatography equipped with inverse chemical suppression and conductivity detection. The best optimization of the chromatographic conditions were achieved when a 100 mm x 7.8 mm ion-exclusion column with a solution of 0.5 mmol L(-1) sulfuric acid as eluent in a flow rate of 0.6 mL min(-1) were employed. The organic acids were sequentially separated in less than 10 min with limits of detection ranging from 1 up to 7.5 micromol L(-1) and limits of quantification from 5 up to 25 micromol L(-1). The linearity of the analytical response was studied in the range of 0.005-10 mmol L(-1) for acetic acid and 0.025-10 mmol L(-1) for propionic and butyric acids with coefficients of determination (R(2)) ranging between 0.9985 and 0.9999. The method was tested and proved to be selective, precise, accurate, reproducible and highly sensitive. Finally, the method was applied in the analysis of biological samples.