No abstract

Grape pomace (GP) is a polyphenolic-rich byproduct of wine production. As most polyphenolics are either bound to cellular matrices or present as free polymeric forms, treatment with hydrolytic enzymes may act to increase GP functionalities. The aim of this study was to examine the impact of tannase alone (T), pectinase plus cellulase (PC) or a mixture of them (TPC) on the hydrolysis of polyphenolics in red GP (RGP), white GP (WGP), and mixed GP (MGP) from Brazilian wine production, as well as antioxidant activity of the products. T was the most potent in increasing total polyphenols in GP by liberating gallic acid, caffeic acid, quercetin, and trans-resveratrol. PC increased the catechin content in RGP and TPC increased the procyanidin B2 in WGP. T treatment of GP was most effective in increasing antioxidant activity. In conclusion, the enzymatic treatment, particularly with T, increases the polyphenolic content and antioxidant activity of GP.

Grape pomace (GP) is rich in polymeric polyphenolics and glycosides which have lower bioefficacy than monomeric and aglycone counterparts. The aim of this study was to determine whether tannin acyl hydrolase [tannase (TNS)] can improve the antioxidant and anti-inflammatory actions of GP in Caco-2 cells treated with IL-1β. TNS increased quercetin content by 45% and decreased quercetin-3-O-rutinoside by 71% as compared to untreated GP. Further, TNS increased total phenols and DPPH, ORAC, and FRAP values by 39, 57, 215, and 12%, respectively. However, GP and GPTNS at 100 and 200 µg/mL (dry extract wt/v) displayed comparable efficacy in the reduction of ROS in Caco-2 cells. After 24 h pre-treatment, GPTNS (200 µg/mL) decreased IL-1β-induced PGE 2 and IL-8 secretion by 107 and 83% respectively, and down-regulated NF-κB activation by 63%. Thus, TNS appears to enhance antioxidant and anti-inflammatory activities of GP polyphenolics and suggests their use as a value-added agroindustrial residue.

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.

No abstract

RESUMO O efeito de doses em cobertura de adubação nitrogenada foi avaliado sobre o rendimento do beneficiamento, a incidência de grãos gessados e barriga branca, os teores ABSTRACT The effect of nitrogen (N) fertilization levels was assessed by the industrial yield, the incidence of chalky and white belly grains as well as protein and amylose content of IRGA 422CLcultivar polished grains. The experiment was consisted with N levels applied in coverage using urea as a N source. The first application (0, 40, 63, 80 and 120kg ha -1 of N) was carried out on a main plot (10x5m) and the second application (0, 25, 50 and 75kg ha -1

No abstract