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Resumen del trabajo presentado al XII Congreso Internacional Nutrición, Alimentación y Dietética, celebrado en Madrid el 11 y 12 de abril de 2018., [Introducción] Inhibitors of α-glucosidase and α-amylase like acarbose provides an approach in the management of the diabetes by delaying carbohydrate digestion, prolonging the overall carbohydrate digestion time, and consequently reducing the rate of glucose absorption. Extracts of olive leaves containing multifunctional bioactive compounds may reduce the postprandial rise in blood glucose, secretion of insulin and the risk for suffering associated infections. Therefore, the extracts are good candidate for treating diabetes and its complications. To the best of our knowledge, no previous studies on the inhibitory effect of Olivactive® on α-glucosidase and α-amylase have been conducted., [Objetivos] The present research aimed to study the inhibitory effects of Olivactive®, a commercial olive (Olea europaea L) leaves extract, on the enzymatic activity of α-glucosidase and α-amylase; as well as, to identify major bioactive compounds contributing to these properties., [Métodos] Bioactive components analyses: Oleuropein and flavonoids in Olivactive® samples were analyzed by high performance liquid chromatography coupled to diode array and mass detectors (HPLC-PAD/MS) according to the method proposed by Inarejos et al., 2009. Quantification of oleuropein and total flavonoids (including Luteolin and Luteolin-7-o-glucoside) were performed by the respective calibration standard curves of Oleuropein (280 nm) and rutin (355 nm). Enzymatic inhibition assay: The study of the inhibition of α-glucosidase by Olivactive® was performed according to Berthelot et al. (1999). Alpha-amylase inhibition assay was performed using the Ultra Amylase Assay Kit - EnzCheck from Thermo Fisher Scientific. Acarbose was employed as inhibitor of reference., [Resultados] Bioactive profile: Oleuropein is the major bioactive component present in Olivactive®, concentrated at 20% (dry weight), whereas total bioflavonoids were about 2% (as rutin equivalents, dry weight). Luteolin and Luteolin-7-glucoside were identified and quantified in Olivactive® in concentrations of 100μg/g and 6mg/g, respectively. Enzymatic inhibition assay: Olivactive® inhibited the activity of α-glucosidase and α-amylase. Acarbose showed IC50 values of 0.012 mg/mL and 19.83 mg/mL for α-glucosidase and α-amylase, respectively. Similar trend was observed for Olivactive® which inhibitory effect was more effective for α-glucosidase (IC50=0.32 mg/mL) than that observed for α-amylase (IC50=57.08 mg/mL)., [Discusión] The presence of Luteolin and Luteolin-7-glucoside in Olivactive® may contribute to the observed inhibitory effect by forming Hbonds between functional groups at the activity sites of α-glucosidase and α-amilase enzymes and the hydroxyl groups forming the B-ring of their flavonoid skeleton (De Sales et al., 2002)., [Conclusiones] Olivactive®, the commercial olive leaf extract standardized to oleuropein and flavonoids by HPLC, may be a good candidate for a better control of diabetics reducing their risk of complications. Further in vivo studies should be conducted to confirm the in vitro preliminary results reported in the present work.

Cocoa bean shells (CBS) is one of the main by-products of the cocoa roasting process, which represents 10% of total weight after the husking and grinding1. CBS is a potential source of dietary fibre and polyphenols recognized as dietary factors responsible for potential beneficial effects on human health. Therefore it could be used as functional ingredient in order to create novel foods with enhanced nutritional value minimizing the volume of agro-industrial wastes. The objective of this research was to evaluate the feasibility of using CBS as a source of antioxidants in yogurt production. CBS powders of different origins (Mexico and São Tomé) were added to yogurt at different concentration (2%, 4% and 6%) and the effect on physico-chemical and microbiological characteristics, total phenolic content and radical scavenging activity were evaluated during storage (21 days). Furthermore in vitro digestion of the different yogurts was performed in order to evaluate the bioaccessibility of phenolic compounds and the antioxidant activity after gastrointestinal digestion as well as to evaluate the effect of food matrix on the bioaccessibility of these active compounds., Journal of International Society of Antioxidants in Nutrition & Health, Vol 3, No 1 (2016): Special Volume of ISANH Conference/Congress