In Vitro Inhibitory Effect on Pancreatic Lipase Activity of Subfractions from Ethanol Extracts of Fermented Oats (Avena sativa L.) and Synergistic Effect of Three Phenolic Acids

Abstract

The purpose of the present work is to study the pancreatic lipase inhibitory effects of different subfractions (n-hexane, ethyl acetate (EA), n-butanol, and water) from ethanol extracts of nonfermented and fungi-fermented oats and to delineate the interactions of three primary phenolic acids in the EA subfractions. The EA subfraction showed the highest inhibitory effect on pancreatic lipase activity at 1.5 mg/mL compared to the other subfractions, regardless of whether the oats were fermented. Meanwhile, both of the EA subfractions of two fungi-fermented oats demonstrated more effective inhibitory activity than that of nonfermented oats. A positive correlation between the total phenolics content and inhibitory activity was found. The inhibitory ability of the EA subfraction from nonfermented or fermented oats also displayed a dose-dependent effect. The standards of caffeic, ferulic, and p-coumaric acids, mainly included in EA subfractions of fermented oats, also displayed a dose-dependent inhibitory effect. A synergistic effect of each binary combination of p-coumaric, ferulic, and caffeic acids was observed, especially at 150.0 μg/mL. Those results indicate that fungi-fermented oats have a more effective inhibitory ability on pancreatic lipase and polyphenols may be the most effective component and could be potentially used for dietary therapy of obesity.

Synergistic interactions of apigenin, naringin, quercetin and emodin on inhibition of 3T3-L1 preadipocyte differentiation and pancreas lipase activity

“…Measurement of lipase activity was adapted from previous reports [20]. Lipase of porcine pancreas type 2 was dissolved in ultrapure water at 5 mg/mL.…”

Inhibition of chrysin on xanthine oxidase activity and its inhibition mechanism

“…The interaction analysis of chrysin with apigenin on XO activity was carried out according to a previous report [16] with slight modifications. V a and V b represent the relative remaining enzymatic activity of XO in the presence of chrysin and apigenin, respectively.…”

“…Theoretically, the possible favorable outcomes for synergism include: increasing the efficacy of the therapeutic effect, decreasing the dosage but increasing or maintaining the same efficacy to avoid toxicity, and providing efficient synergism against target [15]. Cai et al have investigated the synergistic effect of the three phenolic acids in fermented oats, their results indicated that each binary combination of p-coumaric, ferulic and caffeic acid has a synergistic effect [16]. Earlier studies have also shown that hesperidin and diazepam have the synergy in terms of sedative and sleeping, the use of hesperidin may thus decrease the effective therapeutic doses of diazepam [17].…”

Mode of pancreatic lipase inhibition activity in vitro by some flavonoids and non-flavonoid polyphenols

“…The inhibition ability of these agricultural products are generally correlated to the phenolic content of their solvent extracts; for example, in our earlier study vigna species of legumes extracts with high polyphenol content showed PL inhibitory activity (Sreerama, Takahashi & Yamaki, 2012). Other studies characterized the lipase inhibitory activity specifically correlated to their content of anthocyanins A C C E P T E D M A N U S C R I P T ACCEPTED MANUSCRIPT 4 (Yao, Xu, Zhang & Lu, 2013), proanthocyanodins (Gu, Hurst, Stuart, & Lambert, 2011;Nakai et al, 2005), flavan-3-ols (catechins) (Grove, Sae-Tan, Kennett & Lambert, 2012;Nakai et al, 2005), and phenolic acids (Cai et al, 2012). In fact polyphenols represent the major class for the PL inhibitors (reviewed by Lunagariya, Patel, Jagtap & Bhutani, 2014).…”