Gastrointestinal metabolism of monomeric and polymeric polyphenols from mango (Mangifera indica L.) bagasse under simulated conditions

Sensory evaluation and in vitro prebiotic effect of (poly)phenols and dietary fiber-rich mango bagasse-enriched confections

Mango bagasse (MB) is a (poly)phenols and fiber (DF)-rich agroindustrial by-product exhibiting health-beneficial properties. This research aimed to design and characterize an MB-added confection and evaluate its prebiotic effect in vitro. A sensory analysis involving 51 children was conducted to select the most accepted formulation. Nine formulations (3k factorial design) were screened through texture profile analysis to select an MBC formulation that was hydrated (1:4 and 1:5 MBC:water) to reduce its hardness, where 1:4 was chosen. Compared to MB, 1:4 formulation showed a higher protein (+1.20-fold) but less DF (-0.62-fold). The confections contained gallic acid, mangiferin, quercetin, and (+)-catechin (234.82-479.69 g/100 g sample) but displayed a lower in vitro accessibility than those from MB. Selected bacterial strains exhibited fermentative activity using MBC as a substrate, which was even better than using MB fiber-only. The results showed the potential of MB to DF and (poly)phenol-rich confections with prebiotic potential.

Identification, Bioaccessibility, and Antioxidant Properties of Phenolic Compounds in Carob Syrup

Carob syrup is a brown, thick syrup produced from carob pulp that can be directly consumed or used as a sweetener, which also finds applications in folk medicinal practices. In this work, the quali-quantitative phenolic profile of five different carob syrups was elucidated before and after in vitro gastro-intestinal digestion. Moreover, the anti-oxidant properties of undigested and digested carob syrups were investigated. A total of 75 phenolic compounds were identified in undigested carob syrups. The most important phenolic compound in all the samples was gallic acid, the concentration of which ranged between 54.28 and 117.73 mg/100 g. Additional compounds belonging to the classes of hydroxybenzoic acids (in particular glycosylated gallic acid derivatives), hydroxycinnamic acids, and flavonoids (especially flavonols) were also identified. During in vitro gastric digestion, gallic acid mono- and di-hexosides were diglycosylated, releasing gallic acid, which was further degraded in ellagic acid through oxidative polymerization in the intestinal phase of the digestion. Ellagic acid was the major compound detected after in vitro gastro-intestinal digestion of carob syrups. With few exceptions, the anti-oxidant properties of carob syrup were preserved even after digestion. Carob syrup can be considered an important source of phenolic compounds with demonstrated positive effects on human health.