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A clear gap with respect to the potential biological properties of wheat flavonoids exists in the available literature. This information is crucial for breeding programs aiming to produce new varieties presenting improved health benefits. Accordingly, advanced breeding lines of whole durum wheat were evaluated in this contribution. The highest recovery of phenolics was achieved using aqueous acetone (50:50, v/v), as verified by multi-response optimization, thus showing that phenolics could be largely underestimated by employing an inappropriate extraction. The concentration of derivatives of apigenin, the main phenolics present, ranged from 63.5 to 80.7%, as evaluated by LC–ESI-QTOF-MS. Phenolics from the breeding line 98 exhibited the highest ability in scavenging peroxyl radicals, reducing power as well as in terms of inhibition of pancreatic lipase activity, a key enzyme regulating the absorption of triacylglycerols. In contrast, none of the samples exhibited a significant anti-diabetic potential. Despite their high concentration compared to that of phenolic acids, results of this work do not support a significant antioxidant and pancreatic lipase inhibitory effect of durum wheat flavonoids. Therefore, breeding programs and animal and/or human trials related to the effect of durum wheat flavonoids on oxidative stress and absorption of triacylglycerols are discouraged at this point.

The Brazilian Food Supplement Law recently recognized that guarana (Paullinia cupana) contains bioactive substances, hence supporting its role as a functional food ingredient. The health benefits of guarana are associated, at least in part, to its phenolic compounds. However, to the best of our knowledge, there is no literature addressing the presence of phenolic compounds in the fraction containing insoluble-bound compounds and its contribution in terms of alpha-glucosidase inhibition. The concentration of phenolic extracts released from the insoluble-bound fraction required to inhibit 50% of alpha-glucosidase (IC50) activity was 5.8-fold lower than that present in the soluble counterpart. Both fractions exhibited a mixed inhibition mode. Fourteen proanthocyanidins (dimers to tetramers) present in the insoluble-bound fraction were tentatively identified by MALDi-TOF-MS. Future studies aiming at increasing the concentration of the soluble counterpart are deemed necessary. The results presented here enhance the phenolic database of guarana and have a practical impact on the procurement of nutraceuticals and functional ingredients related to the prevention and/or management of type 2 diabetes. The Brazilian normative on food supplements has been recently revised. This study lends support to the future inclusion of guarana powder in the list of sources of proanthocyanidins for the industry of food supplements.

The aim of this study was to evaluate the effects of the processing stages of yerba maté (Ilex paraguariensis) on the moisture content of the leaves and the efficiency of the aqueous extraction of some bioactive substances. Samples of yerba maté were analyzed for caffeine, phenolic acids (caffeic acid, 5-caffeoilquinic acid) and flavonoids (quercetin, kaempferol and myricetin) by HPLC equipped with a diode array detector. Processing widely influenced the caffeine and 5-caffeoilquinic acid content of the aqueous extract (p < 0.05), which was related to the moisture content of the leaves. Caffeic acid was present in 45% of the in infusions from dried mate leaves. Quercetin, myricetin and kaempferol were not detected.A erva mate (Ilex paraguariensis) é a matéria prima para três tipos de bebidas largamente consumidas na América do Sul. Substâncias bioativas presentes neste produto como a cafeína e os ácidos clorogênicos têm recebido especial atenção da comunidade científica. O objetivo deste trabalho é avaliar o efeito do processamento da erva mate no teor de umidade das folhas e a eficiência da extração aquosa de algumas substâncias bioativas. Amostras de erva mate coletadas no Paraná, Brasil foram objeto deste estudo. Cafeína, ácidos fenólicos (ácido cafeico e ácido 5-cafeoilquinico) e flavonóides (quercitina, miricetina e caempferol) foram analisados por HPLC equipado com detector de arranjo de diodos. Os teores de ácido 5-cafeoilquinico e cafeína do extrato aquoso variam em função da etapa do processamento (p0,9). O ácido cafeico foi determinado em 45% das infusões obtidas das folhas secas e quercitina, miricetina e caempferol não foram detectados nesses extratos.

Peanut skin is a rich source of bioactive compounds which may be able to reduce the risk factors associated with metabolic syndromes. This study aimed to characterize bio-compounds from peanut skin (Arachis hypogaea) and their bioactivity (antioxidant activity, inhibition of lipase, and carbohydrase enzymes) and to evaluate their anti-proliferative properties in colorectal cancer cells (HCT116) upon in vitro digestion. Peanut skin was digested in two sequential phases, and the final content, named phase-1 (P1) and phase-2 (P2) extracts, was evaluated. Several bioactive compounds were positively identified and quantified by liquid chromatography, including quinic acid, released especially after in vitro digestion. The total phenolic content and, regardless of the method, the antioxidant activity of P1 was higher than P2. P1 also showed a lower enzyme inhibitory concentration IC50 than P2, lipase, and α-glucosidase. For cell viability in HCT116 cells, lower concentrations of P1 were found for IC50 compared to P2. In conclusion, bioactive compounds were released mainly during the first phase of the in vitro digestion. The digested samples presented antioxidant activity, enzyme inhibitory activity, and cancer cell cytotoxicity, especially those from the P1 extract. The potential applications of such a by-product in human health are reported.