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Quinoa stalks glucuronoarabinoxylan (QSGAX) has been extracted by alkali and further utilized for production of two-types of xylooligosaccharides (XOs): i) enzymatically produced glucuronosylated-XOs (GXOs), and ii) a dilute acid produced mixture of non-substituted/substituted XOs of different degree of polymerization (DP). The respective mixtures were then separately evaluated as prebiotics by analysis of their consumption by two phylogenetically different potential probiotic bacterial strains (Bifidobacterium adolescentis ATCC15703 and Weissella cibaria strain 92), from which release of short chain fatty acids (SCFA) was also monitored. The GXOs mixture was produced using a glucuronosyl-requiring family 30 glycoside hydrolase (GH) Bacteroides ovatus (BoXyn30A), while the XOs mixture was produced by a 30 min acid treatment of QSGAX with H2SO4 [24.5 g/L] at 90 °C. B. adolescentis consumed both GXOs and XOs (DP 2–6), in both cases releasing acetate, lactate, propionate, formate and butyrate as metabolic products. W. cibaria only consumed XOs (DP 2–4), releasing acetate, lactate and minor amounts of butyrate. This is the first study reporting the ability of GXOs consumption by B. adolescentis and shows the potential of GXOs to selectively stimulate B. adolescentis, while XOs stimulated both types of potential probiotics (B. adolescentis ATCC15703 and W. cibaria strain 92).

The genotoxic potential of solutions of the textile dye “Reactive Black 5” that were subjected to decolorizing treatments with the fungal strains Coriolopsis polyzona MUCL33483 , Penicillium sp. MUBA001 and Pycnoporus sp. MUBA002 was tested. The genotoxicity of the solutions was determined by evaluation of micronuclei formation in Vicia faba root cells and calculation of a damage index (MN ID ). Non-treated Reactive Black 5 solutions (50–1000 ppm) caused a statistically significant increase in micronuclei formation and, by then, in damage index. Solutions of dye treated with C. polyzona MUCL33483 and Pycnoporus sp. MUBA002 showed color loss, probably due to enzymatic breakdown of the colorant, but maintenance or even an increase in genotoxicity. On the other hand, the Penicillium sp. strain MUBA001 caused decolorization of the dye, apparently by adsorption on mycelia, and, for solutions that initially contained 50 ppm of colorant, an elimination of the genotoxicity was observed after three weeks of treatment.