Synbiotic Sapota-do-Solimões (Quararibea cordata Vischer) Juice Improves Gut Microbiota and Short-Chain Fatty Acid Production in an In Vitro Model.

Sapota-do-Solimões (Quararibea cordata Vischer) is Amazon South América fruit found in Brazil, Colombia, Ecuador, and Peru. The orange-yellow fruit is usually eaten out of hand or as juice. Despite being a source of carotenoids and dietary fibers (pectin) that can reach the colon and act as an energy source for intestinal microbiota, the fruit is rarely known outside of South America. The symbiotic juice was prepared by fermenting the fruit juice with Lacticaseibacillus casei B-442 and adding prebiotic fructooligosaccharides (FOS, 7% w/v). This study evaluated the functional juice immediately after L. casei fermentation (SSJ0) and after 30 days of cold storage (SSJ30) regarding its effect on human colonic microbiota composition after in vitro fermentation. Fecal samples were collected from two healthy female volunteers, and the 16s rRNA gene sequencing analyzed the fecal microbiota composition. In vitro, colonic fermentation was performed using a batch bioreactor to simulate gastrointestinal conditions. The L. casei viability did not change significantly after 30 days of the synbiotic juice cold storage (4 °C). After the colonic fermentation, the relative abundance of Firmicutes decreased while Proteobacteria and Actinobacteria increased. Regarding short-chain fatty acid (SCFA) production by fecal colonic microbiota, the butyric acid was higher after sample SSJ0 fecal fermentation. In contrast, propionic, isobutyric, and acetic acids were higher after SSJ30 sample fecal fermentation. This study contributes to understanding the interactions between specific foods and the gut microbiota, which can affect human health and well-being.

An overview on the conversion of glycerol to value-added industrial products via chemical and biochemical routes.

Glycerol is a common by-product of industrial biodiesel syntheses. Due to its properties, availability, and versatility, residual glycerol can be used as a raw material in the production of high value-added industrial inputs and outputs. In particular, products like hydrogen, propylene glycol, acrolein, epichlorohydrin, dioxalane and dioxane, glycerol carbonate, n-butanol, citric acid, ethanol, butanol, propionic acid, (mono-, di-, and triacylglycerols), cynamoil esters, glycerol acetate, benzoic acid, and other applications. In this context, the present study presents a critical evaluation of the innovative technologies based on the use of residual glycerol in different industries, including the pharmaceutical, textile, food, cosmetic, and energy sectors. Chemical and biochemical catalysts in the transformation of residual glycerol are explored, along with the factors to be considered regarding the choice of catalyst route used in the conversion process, aiming at improving the production of these industrial products.

Different strategies to co-immobilize dextransucrase and dextranase onto agarose based supports: Operational stability study.

Co-immobilization is a groundbreaking technique for enzymatic catalysis, sometimes strategic, as for dextransucrase and dextranase. In this approach, dextranase hydrolytic action removes the dextran layer that covers dextransucrase reactive groups, improving the immobilization. Another advantage is the synergic effect of the two enzymes towards prebiotic oligosaccharides production. Thus, both enzymes were co-immobilized onto the heterobifunctional support Amino-Epoxy-Glyoxyl-Agarose (AMEG) and the ion exchanger support monoaminoethyl-N-ethyl-agarose (Manae) at pH 5.2 and 10, followed or not by glutaraldehyde treatment. This work is the first attempt to immobilize dextransucrase under alkaline conditions. The immobilized dextransucrase on AMEG support at pH 10 (12.78 ± 0.70 U/g) presents a similar activity of the biocatalyst produced at pH 5.2 (14.95 ± 0.82 U/g). The activity of dextranase immobilized onto Manae was 5-fold higher than the obtained onto AMEG support. However, the operational stability test showed that the biocatalyst produced on AMEG at pH 5.2 kept >60% of both enzyme activities for five batches. The glutaraldehyde treatment was not worthwhile to improve the operational stability of this biocatalyst.