The inhibitory activity and binding characteristics of caffeic acid, p-coumaric acid, quercetin and capsaicin, four phenolic compounds found in hot pepper, against porcine pancreatic lipase activity were studied and compared to hot pepper extract. Quercetin was the strongest inhibitor (IC50=(6.1±2.4) µM), followed by p-coumaric acid ((170.2±20.6) µM) and caffeic acid ((401.5±32.1) µM), while capsaicin and a hot pepper extract had very low inhibitory activity. All polyphenolic compounds showed a mixed-type inhibition. Fluorescence spectroscopy studies showed that polyphenolic compounds had the ability to quench the intrinsic fluorescence of pancreatic lipase by a static mechanism. The sequence of Stern-Volmer constant was quercetin, followed by caffeic and p-coumaric acids. Molecular docking studies showed that caffeic acid, quercetin and p-coumaric acid bound near the active site, while capsaicin bound far away from the active site. Hydrogen bonds and π-stacking hydrophobic interactions are the main pancreatic lipase-polyphenolic compound interactions observed.
1 January 2009 in International Journal of Food Sciences and Nutrition
The objective of this research was to study the biochemical composition and physicochemical properties of three different flours prepared from broccoli crop remains. Florets, leaves and stalks of broccoli were dried at 60°C, and the flours obtained were analysed for proximate composition, amino acid profile, fatty acid composition, and physicochemical properties. The florets flour showed the highest protein content (22.41 g/100 g dry weight); ash was higher in leaves flour (14.67 g/100 g dry weight), and the lipid content was similar in the flours of leaves and stalks. The stalks flour had high crude fibre content and low protein content. All flours presented a high water absorption index. Tyrosine, aspartic acid, glutamic acid, proline and valine were found in larger concentration. The most abundant fatty acids in the lipids were linolenic acid (C18:3n3), palmitic acid (C16:0) and linoleic acid (C18:2n6). Broccoli flours prepared in this study are good source of nutrients and could be utilized as dietary supplements.
Semen cryopreservation damages sperm due to oxidative stress. This study evaluated the antioxidant capacity of Moringa oleifera seed extract in cryopreserved ram semen and the impact of the extract on sperm characteristics. Semen from eight hair rams (four rams per sampling) was allocated into four groups, according to their treatment prior to cryopreservation: Control (no extract), 0.5 (M0.5), 5.0 (M5.0), and 10.0 (M10) mg/mL of M. oleifera extract. The antioxidant activity (ferric reducing antioxidant power, FRAP) and the spermatic characteristics (sperm viability; progressive motility; fast motility; slow motility; acrosome damage; membrane damage; and mitochondrial activity) were assessed post-thawing. Variables were evaluated with analysis of variance followed by Tukey test. While no significant differences were detected in acrosomal damage, mitochondrial activity, fast-, or slow motility, the antioxidant activity was higher (P < 0.05) in M0.5 and M5 treatments. Viability and progressive motility increased in the M0.5 group (P < 0.05), whereas sperm membrane damage was lower (P < 0.05) in the same treatment. In conclusion, supplementation of ram semen with M. oleifera seed extract enhances antioxidant activity, sperm membrane integrity, viability, and progressive motility after thawing. This suggests that M. oleifera extract could be used as an antioxidant to improve the outcome of semen cryopreservation.