Structure and In Vitro Fermentation Characteristics of Polysaccharides Sequentially Extracted from Goji Berry (Lycium barbarum) Leaves

Abstract

Herein, the chelating agent-soluble fraction (CA), sodium carbonate-soluble fraction (SC), and sodium hydroxide-soluble fraction (SH) were sequentially extracted from the cell wall of goji berry (Lycium barbarum) leaves. Furthermore, SC was purified with Q-Sepharose fast flow resin to obtain the neutral sugar fraction (SC-I) and acid sugar fraction (SC-II). Physicochemical properties of polysaccharides were characterized by high-performance anion-exchange chromatography with pulsed amperometry detection, size exclusion chromatography–multi-angle laser light scattering, Fourier transform infrared spectroscopy, nuclear magnetic resonance, and atomic force microscopy analysis. Additionally, the impact of polysaccharides on modulating human gut microbiota was investigated by in vitro fermentation. A high amount of galacturonic acid (GalA) in CA showed that it was an aggregation of linear homogalacturonan. SC was the main pectic polysaccharide fraction and rich in neutral sugars. SC-I was the neutral sugar fraction with an extremely high molecular weight (2.055 × 106 Da), while SC-II was the acid sugar fraction with a low molecular weight (1.766 × 105 Da). SH seemed like a mixture of pectin and hemicellulose. All the five polysaccharides significantly (P < 0.05) increased the abundance of Bacteroides, Bifidobacteria, and Lactobacilli. To the best of our knowledge, this is the first report on the structure and fermentation characteristics of goji berry leaf polysaccharides, which is meaningful to provide a structural basis for further bioactivity research.

Extensive Analysis of Mulberry (Morus rubra L.) Polysaccharides with Different Maturities by Using Two-Step Extraction and LC/QqQ-MS

“…The lyophilized sample was ground into powder (100 mesh), and the powder was stirred with five volumes of ethanol for 30 min three times to remove soluble sugar and pigments, followed by 50% ethanol twice to prepare the mulberry alcohol insoluble solids (AISs). 14 Sequential Extraction. After pretreatment, mulberry powder was disrupted by bead blasting with stainless steel magnetic beads at 60 Hz for 2 min using a Bead Mill Homogenizer for cell wall disruption (JXFSTPRP-24L, Shanghai JingXin, China).…”

“…Based on a comprehensive analysis of existing literature and our laboratory research, it has been indicated that a more efficient and thorough extraction of plant polysaccharides can be achieved through a two-step extraction method involving the use of EDTA followed by NaOH. 9,14,15 Analyzing the presence of multiple monosaccharides and glycosidic linkages in plant polysaccharides is another significant challenge. There have been more than 30 monosaccharides and 80 glycosidic linkages reported in plant polysaccharides by traditional methods, involving gas chromatography coupled with mass spectrometry (GC−MS), capillary electrophoresis (CE), high-performance liquid chromatography (HPLC), and high-pH anion-exchange chromatography (HPAEC).…”

“…There are various extraction procedures for extraction plant polysaccharides, such as hot water, acid, alkali, and chelating agent treatments with varying temperature and condition, which result in inconsistent structural information on plant polysaccharides, even from the same plant species within the same laboratory. , The sequential extraction technique is commonly employed to investigate the structure of plant polysaccharides. , However, the sequential extraction steps are cumbersome for batch processing, and the workflow needs to be improved. Based on a comprehensive analysis of existing literature and our laboratory research, it has been indicated that a more efficient and thorough extraction of plant polysaccharides can be achieved through a two-step extraction method involving the use of EDTA followed by NaOH. ,, …”

Effects of Lycium barbarum Polysaccharides on Immunity and Metabolic Syndrome Associated with the Modulation of Gut Microbiota: A Review

“…These polysaccharide utilizers contain various GHs and PLs which are responsible for the degradation of polysaccharides [ 7 ]. We found that the various types of LBPs in similar experimental models could increase the level of Bacteroides , such as in the fermentation of arabinogalactan-type [ 25 ] and pectin-type [ 87 ] LBPs by the human gut microbiota in vitro. Similarly, Akkermansia , hailed as an emerging “second generation” probiotic, was also markedly elevated in Kunming mice with a normal diet [ 81 ] and in C57BL/6J mice with a normal diet [ 88 ] by different LBPs.…”

Functional Properties of Soluble Fibers from Artichoke Agroindustrial Wastes Isolated through Convective or Microwave Heating and Enzymatic Hydrolysis

“…4,9 Pectin is a family of complex polysaccharides from the primary cell walls of plants consisting mainly of polymers rich in galacturonic acid (GalA) with significant amounts of rhamnose, arabinose, and galactose as well as other monosaccharides. 10 Pectin is considered a soluble dietary fiber and is widely used in the food industry as a gelling and thickening agent.…”