Effect of enzymatic treatment of citrus by-products on bacterial growth, adhesion and cytokine production by Caco-2 cells

Citrus by-products are inexpensive sources of polyphenols, important bioactive compounds with wide pharmaceutical and food applications. This study aimed to investigate the effect of enzymatic treatment of citrus by-products on the polyphenolic profile of extracts and assess the influence of extracts on the growth and adhesion of probiotics and foodborne pathogenic bacteria and on the inflammatory response of epithelial cells. Enzyme-assisted extraction altered the polyphenolic profile (as assessed by HPLC-DAD), increasing the content of aglycone flavanones (naringenin and hesperetin). Enzymatic extracts and aglycone flavanones exhibited higher antibacterial and prebiotic activities than non-enzymatic extracts and glycoside flavanones. However, a higher content of aglycones was not associated with higher anti-adhesion activity. Citrus extracts significantly (P ≤ 0.05) decreased the inflammatory response of Caco-2 cells to Salmonella Typhimurium adhesion. These results support the sustainable reuse of citrus agroindustrial wastes and indicate the potential of citrus extracts in preventing infection by foodborne pathogenic bacteria and inducing proliferation of probiotics in foods and the gut environment.

Passion fruit (Passiflora edulis) leaf aqueous extract ameliorates intestinal epithelial barrier dysfunction and reverts inflammatory parameters in Caco-2 cells monolayer

The aqueous extract of Passiflora edulis leaves is rich in bioactive polyphenolics, with antioxidant and anti-inflammatory properties. In this study, the recovery of barrier dysfunction and the anti-inflammatory effect of P. edulis leaf aqueous extract (PELE) were evaluated using a Caco-2 monolayer model challenged with IL-1β and LPS. After inflammatory stimuli, it was observed a 28% reduction in transepithelial electrical resistance (TER) and 78% increase of LY permeability. After 48-h treatment with PELE (10 mg mL^-1), the monolayer showed 35% increase in TER after inflammatory decreases, and 67% lower LY paracellular permeability, showing a recovery of the monolayer integrity. The treatment also suppressed IL-8 production in 65%. Our results suggest that PELE is a potent source of antioxidants that may promote a protective effect by repairing the intestinal epithelial integrity.

Biotransformation processes in soymilk isoflavones to enhance anti-inflammatory potential in intestinal cellular model

The present study investigated, in in vitro cellular model, the modulation of intestinal inflammation by biotransformed soymilk with tannase and probiotic strains. The ability to reduce the generation of intracellular reactive oxygen species (ROS) and the antioxidant power of soy extracts were also evaluated. The results showed changes in isoflavones profile after biotransformation processes, with a significative enhancement in aglycones content. Reduction in intracellular ROS production and improvement in antioxidant capacity were observed. Anti-inflammatory responses in Caco-2 cells were also expressive. A significative decrease in interleukin 8 (IL-8) level was detected for all biotransformed samples, especially for extracts with tannase. The biotransformed soy extracts by tannase have a great potential to improve health conditions, defending the intestinal cells of oxidative damage, and acting as a possible adjuvant in inflammatory process. PRACTICAL APPLICATIONS: Soy isoflavones have been explored owing to health benefits. Only glycosylated forms are found in high concentrations in soybeans. So, microbial and enzymatic biotransformation processes aiming to increase aglycones and metabolites appear as an attractive option to enlarge the bioactivity of soy products. The present study showed a positive impact of biotransformed soymilk on antioxidant defenses systems and modulation of intestinal inflammation and could act as a nutraceutical agent.

Antioxidant Potential and Modulatory Effects of Restructured Lipids from the Amazonian Palms on Liver Cells

Enzymatic interesterification is used to manipulate oil and fat in order to obtain improved restructured lipids with desired technological properties. However, with raw materials containing significant amounts of bioactive compounds, the influence of this enzymatic process on the bioactivity of the final product is still not clear. Thus, the aim of this study is to evaluate the antioxidant potential and modulatory effects of two raw materials from the Amazonian area, buriti oil and murumuru fat, before and after lipase interesterification, on human hepatoma cells (HepG2). The results indicate that minor bioactive compounds naturally found in the raw materials and their antioxidant capacity are preserved after enzymatic interesterification, and that the restructured lipids modulate HepG2 endogenous antioxidant enzyme.

Influence of rye flour enzymatic biotransformation on the antioxidant capacity and transepithelial transport of phenolic acids

Enzymatic biotransformation enhanced the release of phenolic acids and Caco-2 transepithelial transport of vanillic acid.

Immobilized tannase treatment alters polyphenolic composition in teas and their potential anti-obesity and hypoglycemic activities in vitro

The aim of this work was to assess the effect of immobilized-tannase treatment on black, green, white and mate tea components and on their bioactivities relevant to obesity. Tannase treatment caused predictable changes in polyphenol composition with substantial reduction in galloylated catechins in green, white and black tea. Mate tea, which is rich in chlorogenic acids, was much less affected by tannase treatment although some degradation of caffeoyl quinic acid derivatives was noted. The original tea samples were effective in inhibiting digestive enzymes in vitro. They inhibited amylase activity, some with IC50 values ∼70 μg mL(-1), but were much less effective against α-glucosidase. They also inhibited lipase activity in vitro and caused dose-dependent reductions in lipid accumulation in cultured adipocytes. The bio-transformed tea samples generally matched the effectiveness of the original samples but in some cases they were markedly improved. In particular, tannase treatment reduced the IC50 value for amylase inhibition for green tea and white tea by 15- and 6-fold respectively. In addition, the bio-transformed samples were more effective than the original samples in preventing lipid accumulation in adipocytes. These in vitro studies indicate that bio-transformed tea polyphenols could assist in the management of obesity through improvement in energy uptake and lipid metabolism and also indicate that biotechnological modification of natural food molecules can improve the benefits of a common beverage such as tea.

Molecular markers for genetic diversity, gene flow and genetic population structure of freshwater mussel species

Freshwater mussel species are in global decline. Anthropogenic changes of river channels and the decrease of autochthonous fish population, the natural hosts of mussels larval stages (glochidia), are the main causes. Therefore, the conservation of mussel species depends not only on habitat conservation, but also on the availability of the fish host. In Portugal, information concerning most of the mussel species is remarkably scarce. One of the most known species, Unio pictorum is also in decline however, in the basins of the rivers Tua and Sabor (Northeast of Portugal), there is some indication of relatively large populations. The aforementioned rivers can be extremely important for this species conservation not only in Portugal, but also in the remaining Iberian Peninsula. Thus, it is important to obtain data concerning Unio pictorum bioecology (distribution, habitat requirements, population structure, genetic variability, reproductive cycle and recruitment rates), as well as the genetic variability and structure of the population. Concomitantly, information concerning fish population structure, the importance of the different fish species as “glochidia” hosts and their appropriate density to allow effective mussel recruitment, will also be assessed. The achieved data is crucial to obtain information to develop effective management measures in order to promote the conservation of this bivalve species, the conservation of autochthonous fish populations, and consequently the integrity of the river habitats.