Purification, Characterization, and Prebiotic Properties of Pectic Oligosaccharides from Orange Peel Wastes

Abstract

Pectic oligosaccharides (POS) were obtained by hydrothermal treatment of orange peel wastes (OPW) and purified by membrane filtration to yield a refined product containing 90 wt % of the target products. AraOS (DP 3-21), GalOS (DP 5-12), and OGalA (DP 2-12, with variable DM) were identified in POS mixtures, but long-chain products were also present. The prebiotic potential of the concentrate was assessed by in vitro fermentation using human fecal inocula. For comparative purposes, similar experiments were performed using orange pectin and commercial fructo-oligosaccharides (FOS) as substrates for fermentation. The dynamics of selected microbial populations was assessed by fluorescent in situ hybridization (FISH). Gas generation, pH, and short-chain fatty acid (SCFA) production were also measured. Under the tested conditions, all of the considered substrates were utilized by the microbiota, and fermentation resulted in increased numbers of all the bacterial groups, but the final profile of the microbial population depended on the considered carbon source. POS boosted particularly the numbers of bifidobacteria and lactobacilli, so that the ratio between the joint counts of both genera and the total cell number increased from 17% in the inocula to 27% upon fermentation. SCFA generation from POS fermentation was similar to that observed with FOS, but pectin fermentation resulted in reduced butyrate generation.

In vitro fermentation of lupin seeds (Lupinus albus) and broad beans (Vicia faba): dynamic modulation of the intestinal microbiota and metabolomic output

“…9,19 However, to the best of our knowledge, this is the first evidence showing the stimulatory effect on intestinal lactobacilli and Atopobium populations after in vitro fermentation with broad beans and lupin seeds. This is an important observation to uphold the robustness of our results since FOS has previously been reported by other authors to enhance the growth of lactobacilli and Atopobium.…”

“…2 Prebiotics are non-digestible by digestive enzymes in the human gut and enter the gut without modifying their structure. 1,[7][8][9] However, few studies have been carried out using food sources rich in prebiotic components without the need to extract these compounds. The beneficial health effects of prebiotics are related to their influence on the gut microbiota composition, to the stimulation of growth, metabolism and activities of lactic acid bacteria, bifidobacteria and other emergent strains such as Roseburia intestinales and Faecalibacterium prausnitzii 3,4 in the human intestine, exerting several functional properties, such as prevention of pathogen adhesion and colonization, modulation of bowel habits, regulation of lipid and glucose metabolism, and the influence of the intestinal metabolome.…”

Extraction optimization and profile analysis of oligosaccharides in banana pulp and peel

“…As expected, the total oligosaccharide content in banana peel was lower than the edible part of fruits (Jovanovic‐Malinovska et al, ). However, the banana peel is rich in soluble and insoluble fibers (pectin, cellulose, and hemicellulose) and can be used to obtain valuable oligosaccharides by appropriate physical and biological processes (Carvalho et al, ; Gómez et al, ).…”

A Novel Non-Cumbersome Approach Towards Biosynthesis of Pectic-Oligosaccharides by Non-Aflatoxigenic Aspergillus sp. Section Flavi Strain EGY1 DSM 101520 through Citrus Pectin Fermentation

“…At most, pectin-containing materials that are good candidates for POS' preparation are pectin-containing feedstocks (e.g., orange peels, lemon peels, apple pomace, sugar beet pulp, etc) [13]. Processing of such materials for synthesis of POS is a multistep procedure, cumbersome, tedious, time consuming and probably expensive.…”