Probiotic fermentation modifies the structures of pectic polysaccharides from carrot pulp

Abstract

Polysaccharides from fermented carrot pulp (WSP-p) show better anti-diabetic effects than those from un-fermented carrot pulp (WSP-n), and functional properties of polysaccharides depend on their structure. In this study, both WSP-p and WSP-n were separated into three homogeneous fractions as WSP-p-1, WSP-p-2, WSP-p-3, WSP-n-1, WSP-n-2 and WSP-n-3.The weight-average molecular weight of all of fractions from WSP-p showed a downward trend compared with the corresponding fraction from WSP-n. The functional groups in WSPp and WSP-n were similar. The morphologies of WSP-p-2 and WSP-p-3 from SEM were similar to those of WSP-n-2 and WSP-n-3, but there were more fragmented particles adhered to WSP-n-1 than to WSP-p-1. Monosaccharide composition and methylation analysis confirmed that WSP-p-1, WSP-p-2, WSP-n-1 and WSP-n-2 were typical rhamnogalacturonan I-type polysaccharides with 1,4-linked -D-galacturonic acid residues, but WSP-p-3 and WSPn-3 contained predominantly homogalacturonan regions with 1,4-GalpA linkages. 1 H and 13 C NMR of fractions from WSP-p showed the similar spectra to those from WSP-n. These findings suggest that probiotic fermentation mainly cleaved the linkages between repeating units within polysaccharides during fermentation, and not only reduced their molecular weight but also improved the homogeneity in their molecular size distribution, which improves their biofunctions.

Applications of infrared spectroscopy in polysaccharide structural analysis: Progress, challenge and perspective

“…Bands in this region can be assigned to stretching vibrations of double bonds. The COO– doublet which is characteristic for pectic polysaccharides is located in this region ( Wan, Hong, Shi, Yin, Koev, Nie, et al, 2021 ). In addition, a water band appears at about 1635 cm −1 in this region and can shift depending on the strength of interactions.…”

Structural Characterization of a Low Molecular Weight HG-Type Pectin From Gougunao Green Tea

“…The hydrolyzate was diluted to be 20 μg/ml and analyzed by a high-performance anion-exchange chromatography with pulsed amperometric detection (Dionex ICS-5000, Thermo Fisher, Waltham, MA, United States). A CarboPac™ PA20 Guard Column (Ø3 mm × 30 mm, Thermo Fisher, Waltham, MA, United States) and CarboPac™ PA20 Analytical Column (Ø3 mm × 150 mm, Thermo Fisher, Waltham, MA, United States) were equipped in series and eluted with the mobile phase at 0.5 ml/min ( 23 ).…”

“…After hydrolysis and acetylation, the partially methylated alditol acetates (PMAAs) were obtained. The PMAAs were analyzed by an Agilent 7890B/7000D GC-MS system (Agilent, Santa Clara, CA, United States) equipped with an SP-2330 column (Sigma-Aldrich, St. Louis, MO, United States) ( 23 ).…”

Effects of Lactobacillus plantarum Fermentation on the Chemical Structure and Antioxidant Activity of Polysaccharides from Bulbs of Lanzhou Lily

“…Previous studies have shown that there are some changes in plant polysaccharides before and after fermentation, which are demonstrated in the monosaccharide composition and biological activity. The changes were found to be related to the changes of carbohydrate active enzymes during fermentation. , In the carrot water-soluble polysaccharide, fermentation by probiotics led to enhanced immune regulation function and anti-diabetic effects. , The soybean soluble polysaccharide fermented by mixed bacteria was better able to promote the growth of microorganisms, and the monosaccharide composition, surface area, functional groups, and crystal structure therein were changed …”

“…9,10 In the carrot water-soluble polysaccharide, fermentation by probiotics led to enhanced immune regulation function and anti-diabetic effects. 11,12 The soybean soluble polysaccharide fermented by mixed bacteria was better able to promote the growth of microorganisms, and the monosaccharide composition, surface area, functional groups, and crystal structure therein were changed. 13 T h i s c o n t e n t i s Lanzhou lily (Lilium davidii var.…”