Sprouting and Hydrolysis as Biotechnological Tools for Development of Nutraceutical Ingredients from Oat Grain and Hull

Oat consumption has increased during the last decade because of the health benefits associated with its soluble dietary fiber (β-glucan), functional proteins, lipids, and the presence of specific phytochemicals, such as avenanthramides. Oat is consumed mainly as whole grain, and the hull (seed coat), comprising 25–35% of the entire grain, is removed, generating a large amount of waste/by-product from the milling industry. The objective of this study was to evaluate the use of biotechnological strategies, such as sprouting for oat grain (OG) and hydrolysis for oat hull (OH), to enhance antioxidant and anti-inflammatory properties and lower the glycemic index (GI). Sprouting produced significant (p ≤ 0.05) increases in free (32.10 to 76.62 mg GAE (100 g)−1) and bound phenols (60.45 to 124.36 mg GAE (100 g)−1), increasing significantly (p ≤ 0.05) the avenanthramide (2c, 2p and 2f) soluble phenolic alkaloid content and anti-inflammatory properties of OG. On the other hand, the hydrolysis of OH using Viscoferm (EH2-OH) and Ultraflo XL (EH21-OH) increased by 4.5 and 5-fold the release of bound phenols, respectively; meanwhile, the use of Viscoferm increased the 4.55-fold soluble β-glucan content in OH, reaching values close to those of OG (4.04 vs. 4.46 g (100 g)−1). The study shows the potential of both strategies to enhance the nutritional and bioactive properties of OG and OH and describes these processes as feasible for the industry to obtain an ingredient with high antioxidant and anti-inflammatory activities. Single or combined biotechnological tools can be used on oat grains and hulls to provide nutraceutical ingredients.

Chemical and Biological Properties of Peach Pomace Encapsulates: Chemometric Modeling

Background: Bioactive compounds need to resist food processing, be released from the food matrix, and be bioaccessible in the gastrointestinal tract in order to provide health benefits. Bioactive compounds isolated from peach pomace (PP) were encapsulated using four different wall materials to improve their stability and to evaluate the effects of in vitro gastrointestinal digestion, as well as chemometric modeling among obtained encapsulates. Methods: Phenolics and carotenoids content, antioxidant, antihyperglycemic, anti-inflammatory, and cell growth activities were evaluated after gastric and intestinal digestion steps. Chemometrics classification analysis–principal component analysis and hierarchical cluster analysis revealed grouping among encapsulates. Results: The encapsulation of PP bioactive compounds showed a protective effect against pH changes and enzymatic activities along digestion, and thereby contributed to an increase in their bioaccessibility in gastric and intestinal fluids. Conclusions: The obtained results suggest protein and polysaccharide carriers and the freeze-drying technique, as an efficient method for the encapsulation of bioactives from PP, could find use in the food and pharmaceutical industry.

A Comparative Analysis of Different Varietal of Fresh and Dried Figs by In Vitro Bioaccessibility of Phenolic Compounds and Antioxidant Activities

Varietal and sun-drying effects on phenolic compounds and their antioxidant activity were investigated during the in vitro gastrointestinal digestion of fresh and dried figs. The total phenolic compounds (phenolic, flavonoids, and proanthocyanidin) and their antioxidant activity (ferric reducing power; free radical scavenging activity DPPH, and phosphomolybdenum test) were evaluated before and after digestion. The total phenolic compounds and the antioxidant capacities of fresh and dried figs obtained before digestion were significantly (p < 0.05) higher than those obtained after digestion. A significant decrease (p < 0.05) of phenolic compounds and their antioxidant activity was observed during different digestion phases (oral phase > gastric phase > intestinal phase). A positive correlation was found between the total phenolic compounds and the antioxidant activity tested for both fresh and dried figs. Furthermore, the results showed that the digestion has no effect on the total phenolic compounds; however, a negative influence of the pH and the enzymes was observed on these compounds and their antioxidant activity. During in vitro gastrointestinal digestion, the varietal and the sun-drying has no significant effect on the phenolic compounds and their antioxidant activity. Likewise, the fresh or dry variety kept a high content before and after the digestion.

Effect of in Vitro Gastrointestinal Digestion on Encapsulated and Nonencapsulated Phenolic Compounds of Carob (Ceratonia siliqua L.) Pulp Extracts and Their Antioxidant Capacity

To determine the effect of in vitro gastrointestinal digestion on the release and antioxidant capacity of encapsulated and nonencapsulated phenolics carob pulp extracts, unripe and ripe carob pulp extracts were microencapsulated with polycaprolactone via double emulsion/solvent evaporation technique. Microcapsules' characterization was performed using scanning electron microscopy and Fourier transform infrared spectrometry analysis. Total phenolics and flavonoids content and antioxidant activities (ORAC, DPPH, and FRAP) were evaluated after each digestion step. The release of phenolic acids and flavonoids was measured along the digestion process by HPLC-MS/MS analysis. The most important phenolics and flavonoids content as well as antioxidant activities were observed after gastric and intestinal phases for nonencapsulated and encapsulated extracts, respectively. The microencapsulation of carob polyphenols showed a protective effect against pH changes and enzymatic activities along digestion, thereby promoting a controlled release and targeted delivery of the encapsulated compound, which contributed to an increase in its bioaccessibility in the gut.

Bacillus cereus Response to a Proanthocyanidin Trimer, a Transcriptional and Functional Analysis

Proanthocyanidins are abundant in peanut skin, and in this study, the antibacterial effects of a peanut skin extract (PSE) against food-borne bacteria were investigated to find its minimum inhibitory concentration. Food-borne gram-positive bacteria, and in particular Bacillus cereus, was more sensitive to PSE. In particular, the inhibitory activity of epicatechin-(4β → 6)-epicatechin-(2β → O→7, 4β → 8)-catechin (EEC), a proanthocyanidin trimer from peanut skin, against B. cereus was stronger than that of procyanidin A1, a proanthocyanidin dimer. DNA microarray analysis of B. cereus treated with EEC was carried out, with a finding that 597 genes were significantly up-regulated. Analysis of the up-regulated genes suggested that EEC disrupted the normal condition of the cell membrane and wall of B. cereus and alter its usual nutritional metabolism. Moreover, treatment of B. cereus with EEC inhibited glucose uptake, suggesting that EEC affects the cell-surface adsorption.