Potentially Bioaccessible Phenolic and Antioxidant Potential of Fresh and Stored Lentil Sprouts—Effect of Lactobacillus plantarum 299v Enrichment

The phenolic and antioxidant potential of potentially bioaccessible fractions of lentil sprouts was studied. Sprouts were cocultivated with a probiotic to obtain a new functional product and further stored in cool conditions. The fraction obtained after buffer extraction and gastric digestion had higher content of phenolics compared to the control (by 20% and 46%, respectively); however, a 9% decrease was observed in samples obtained after gastrointestinal digestion. After gastrointestinal digestion, the highest content of phenolics (278 µg/g d.w.) was determined in the fresh control sprouts. Compounds neutralizing ABTS and hydroxyl radicals, chelating metal ions, and exhibiting strong reducing power were effectively released after gastrointestinal digestion (e.g., the values of the gastrointestinal digestibility index for chelating power and ability to quench hydroxyl radicals significantly exceeded 1 in all studied samples). It was proved that the enrichment of sprouts with a probiotic and further storage significantly improved the antioxidant potential; compared to the fresh control sprouts, an increase by 45% and 10% was determined after the gastric and gastrointestinal digestion, respectively. Lentil sprouts enriched with L. plantarum 299v may be a new functional product characterized by the high antioxidant capacity of the potentially bioaccessible fraction.

AVALIAÇÃO DA CONCENTRAÇÃO TOTAL E DA FRAÇÃO BIOACESSÍVEL DE METAIS EM AMOSTRAS DE CASCA DE UVA DE CULTIVARES TANNAT E CABERNET SAUVIGNON POR MIP OES

EVALUATION OF THE TOTAL CONCENTRATION AND THE BIOACCESSIBLE FRACTION OF METALS IN SAMPLES OF GRAPE SKINS OF CULTIVARS TANNAT AND CABERNET SAUVIGNON BY MIP OES. This paper describes the evaluation of the total concentration of Ba, Bi, Ca, Cd, Co, Cr, Cu, Fe, K, Mn, Pb e Zn and the bioaccessible fraction of Ba, Cu, Fe, Mn, Pb and Zn in samples of grape skins from different cultivars (Vitis Viníferas Tannat and Cabernet Sauvignon) by MIP OES. For the determination of total concentration, acid decomposition with a reflux system adapted to the digestion tubes in the oxidizing medium of HNO3 and H2O2 were used. The accuracy of the method was verified by recovery tests, whose values ranged from 80 to 120%, as well as through a comparative method in closed system. Bi, Cd and Cr showed values for total content below the LOD or below the values acceptable for health while Pb is higher than 0.2 mg kg-1, for both cultivars. To evaluate the bioacessible fraction, the gastrointestinal system was simulated using an in vitro procedure, and its performance was assessed considering the bioaccessible fraction (supernatant) and the non-bioaccessible fraction, whose sum should be closed to the total concentration, and the results obtained were between 81 and 120%. Both cultivars showed similar values for the bioaccessible fractions (~13.5 – 53% of the total content).

Nitrated monoaromatic hydrocarbons (nitrophenols, nitrocatechols, nitrosalicylic acids) in ambient air: levels, mass size distributions and inhalation bioaccessibility

Nitrated monoaromatic hydrocarbons (NMAHs) are ubiquitous in the environment and an important part of atmospheric humic-like substances (HULIS) and brown carbon. They are ecotoxic and with underresearched toxic potential for humans. NMAHs were determined in size-segregated ambient particulate matter collected at two urban sites in central Europe, Ostrava and Kladno, Czech Republic. The average sums of 12 NMAHs (Σ12NMAH) measured in winter PM10 samples from Ostrava and Kladno were 102 and 93 ng m−3, respectively, and 8.8 ng m−3 in summer PM10 samples from Ostrava. The concentrations in winter corresponded to 6.3–7.3% and 2.6–3.1% of HULIS-C and water-soluble organic carbon (WSOC), respectively. Nitrocatechols represented 67–93%, 61–73% and 28–96% of NMAHs in PM10 samples collected in winter and summer at Ostrava and in winter at Kladno, respectively. The mass size distribution of the targeted substance classes peaked in the submicrometre size fractions (PM1), often in the PM0.5 size fraction especially in summer. The bioaccessible fraction of NMAHs was determined by leaching PM3 samples in two simulated lung fluids, Gamble’s solution and artificial lysosomal fluid (ALF). More than half of NMAH mass is found bioaccessible, almost complete for nitrosalicylic acids. The bioaccessible fraction was generally higher when using ALF (mimics the chemical environment created by macrophage activity, pH 4.5) than Gamble’s solution (pH 7.4). Bioaccessibility may be negligible for lipophilic substances (i.e. log KOW > 4.5).