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The aim of this study was to model the extraction of phenolic antioxidants and identify the principal individual phenolic compounds of white tea by LC-DAD-MS/MS. A Box-Behnken design was applied to evaluate the effects of time, temperature and ethanol concentration in the extraction of phenolics and in vitro antioxidant activity. All mathematical models proposed by multiple regression analysis were significant (P < 0.001) and could explain up to more than 85% of the variance (R 2 adj > 0.80). A simultaneous optimization was performed using DPPH, ABTS, FRAP, (−)-epigallocatechin gallate, and (−)-epicatechin gallate to maximize the phenolic extraction and suggested optimum conditions of 10 min, 66 °C and 30% ethanol solution, with absolute error lower than 7%. The suggested optimum conditions were confirmed by external validation. The principal individual compounds identified by mass spectrometry were gallic acid, 5-galloylquinic acid, caffeine, theobromine, gallocatechin, epigallocatechin, epicatechin, epigallocatechin gallate, and epicatechin gallate. [ABSTRACT FROM AUTHOR]

The nutritional and antioxidant activity of two species of leafy vegetable Basella were investigated. The moisture content of Basella alba and Basella rubra leaves was 928 and 930 g/kg, respectively. The dietary fibre content constitutes 32 g, 10 g and 22 g total, soluble and insoluble dietary fibre, respectively, in 100 g of dry B. alba leaves. The leaves of Basella spp. are very low in calories (95–110/100 g) and fats, but holds a good amount of vitamins, minerals, and antioxidants. The betalains content in B. rubra was highest in 20 weeks old leaves (80 mg) and vitamin C content of B. alba was more (74 mg) than B. rubra (67 mg) in 100 g fresh leaves. The EC 50 values were found high in BAW extract (3.4 mg/mL) for DPPH radical scavenging activity. BAW extract (1.04) at 50 mg/mL showed high ferric reducing antioxidant power and least in BAM extract. Various extracts from leaves with different constituents were shown dose dependent antioxidant and high scavenging abilities which play a key role in combating the reactive oxygen species. In view of this, Basella spp. could be an excellent example of 'functional food' that aims at lowering the risk of various diseases. [ABSTRACT FROM AUTHOR]

Nowadays, in the food it is common market to develop healthier products aiming at health benefits. Among the alternatives, there are products with the addition of aromatic herbs, since, throughout the storage period, they enhance the preservation of the desirable properties of these foods by preventing/delaying oxidative processes. In this work the efficiency of three concentrations (0.50, 1.00, and 1.50%) of Salvia officinalis powder in salmon hamburgers were investigated. The results showed that Salvia officinalis was able to stop the oxidation process of the meat matrix under analysis, presenting a good antioxidant and antimicrobial potential under the conditions of raw and grilled hamburgers. Therefore, through the analyzes performed, it was possible to predict that Salvia officinalis is a good strategy for the food industry when it comes to preserving salmon meat for a long period of storage, in this case being studied for 90 days. • The Salmon is a rich fish in polyunsaturated fatty acids beneficial to health. • The Salvia officinalis contributed to higher antioxidant and antimicrobial activity in salmon. • The raw and grilled hamburgers were preserved by the herb. [ABSTRACT FROM AUTHOR]

Açaí seed extracts are reported for containing polyphenols with pharmacological properties against inflammation, hypertension, and metabolic syndrome. However, presently, those seeds accumulate as waste, causing environmental problems. Therefore, we aimed to characterize the polyphenol profile of açaí seed extracts to investigate its composition and biological effects. Multiple techniques were used for the identification of the extract's metabolites, such as HPLC, mass spectrometry, and mass spectrometry imaging (MALDI-IMS). The extract was majorly composed of B-type and A-type oligomeric procyanidins with a mean degree of polymerization of 11.4 (>3000 Da), formed by catechin and epicatechin as starter and extension subunits, respectively. MALDI-IMS confirmed, for the first time, the presence of A-type procyanidins in the seed's tegument. The extract was not cytotoxic to THP1 (macrophage cell line) and LLC-MK2 (epithelial cell) and, moreover, it efficiently protected macrophages from oxidative stress, which correlated to its high antioxidant capacity, confirmed by DPPH, TEAC and ORAC methods. Additionally, the extract presented antimicrobial activity against gram-positive bacterial strains and Candida albicans. These data indicate the potential use of seed extracts for cosmetic and pharmaceutical formulations. Image 1 • The extract is composed of B- and A-types oligomeric procyanidins (>3000 Da). • MALDI-IMS was used to identify procyanidins in situ for the first time. • Procyanidins were active against gram-positive bacteria and C. albicans. • The extract was not cytotoxic for mammalian cells. • Açaí seed extract has a high antioxidant activity that prevents oxidative stress. [ABSTRACT FROM AUTHOR]