Dados do Trabalho

Título

DYNAMICS OF MODULATION OF THE HUMAN INTESTINAL MICROBIOTA IN VITRO FROM POTENTIAL PREBIOTIC OLIGOSACCHARIDES OBTAINED FROM LIGNOCELLULOSIC WASTES

Introdução

Lignocellulosic agro-industrial wastes are considered materials with low added value, often discarded by industries. However, studies have demonstrated its high potential for application in the production of potentially prebiotic oligosaccharides such as xylo-oligosaccharides (XOS) and cello-oligosaccharides (COS). The objective and differential of this study is to evaluate the effect of XOS and COS obtained from the enzymatic hydrolysis of sugarcane bagasse (SB) and corn husks (CH), on the modulation dynamics of the human intestinal microbiota in vitro.

Material e Métodos

Sugarcane bagasse and corn husks were subjected to the alkaline process (5% KOH, 10% solids load, 121 ºC, 1 atm, 15 min). The hemicelluloses and celluloses were subjected to the enzymatic hydrolysis process (pH 5.0, 50 ºC, 2% solids load, 200 rpm), applying the Shearzyme and Celluclast cocktails (Novozymes ®) to produce XOS and COS respectively, during 48 h. The concentrated and standardized hydrolysates containing XOS and COS of SB and CH were fermented in vitro (static, 37 ºC, 24 h) in anaerobic flasks using the fecal microbiota of five healthy volunteers. Genomic DNA (gDNA) was extracted and purified from the NZY Tissue gDNA Isolation kit. Taxonomic analysis of microbial communities was analyzed using Illumina 16S rRNA sequencing.

Resultados e Discussão

The best tests for obtaining XOS were achieved after 48 h, reaching 7.47 and 4.41 g/L for SB and CH respectively. Similarly, the best COS productions occurred after 48h, reaching 0.27 and 0.46 g/L for SB and CH respectively. During the initial 12 h of colonic fermentation, a rapid increase in relative optical density was observed, in addition to a reduction in pH, especially for COS from SB and CH, in addition to XOS from SB. The XOS and COS of SB and CH significantly stimulated the growth of probiotic strains of Lactobacillus and Bifidobacterium, triggering a beneficial effect on the composition of the intestinal microbiota. A greater amount of short-chain fatty acids was produced by the microbial fermentation of COS and XOS of SB and CH, highlighting mainly lactate, acetate, propionate, and isobutyrate.

Conclusão

Results indicate that XOS and COS of lignocellulosic wastes exhibit promising potential as nutraceutical ingredients for positive human gut microbiota modulation.