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Highlights • The structure of a pectin polysaccharide LBP1C-2 was characterized. • The backbone of the polysaccharide LBP1C-2 was alternate 1, 4-α-Gal p A and 1, 2-α-Rha p. • LBP1C-2 inhibited Aβ 42 production in a dose-dependent manner with no cytotoxicity. • LBP1C-2 decreases Aβ 42 production through mediating BACE1 and ADAM10 as well as IDE expression. Abstract Here, a pectin LBP1C-2 with the molecular weight of 99.8 kDa was purified from fruits of Lycium barbarum L. Its structure was elucidated as a backbone of alternate 1, 2-linked α-Rha p and 1, 4-linked α-Gal p A, with branches of terminal (T) -, 1, 3-, 1, 6- and 1, 3, 6-linked β-Gal p , T-, 1, 5- and 1, 3, 5-linked α-Ara f and T-linked β-Rha p substituted at C-4 of 1, 2, 4-linked α-Rha p. The cell-based experiments indicated that LBP1C-2 suppressed Aβ 42 production in a dose-dependent manner with no cytotoxicity. Further study showed that expression of β-site APP cleaving enzyme 1 (BACE1) was attenuated by LBP1C-2, while expression of ADAM10 was up-regulated by LBP1C-2. Moreover, LBP1C-2 promoted the expression of insulin-degradation enzyme (IDE). These results suggested that LBP1C-2 might be a leading compound for anti-Alzheimer’s disease therapy by decreasing Aβ 42 production through mediating BACE1 and ADAM10 as well as IDE expression. [ABSTRACT FROM AUTHOR]

An acidic polysaccharide, named as p -LBP, was isolated from Lycium barbarum L. by water extraction and purified by decoloration, ion exchange chromatography, dialysis and gel chromatography, successively. The primary structure analysis was determined by HPAEC-PAD, HPSEC, FT-IR, GC–MS, and NMR. The results showed p -LBP was a homogeneous heteropolysaccharide as a pectin molecule with an average molecular weight of 64 kDa p -LBP was an approximately 87 nm hollow sphere in 0.05 mol/L sodium sulfate solution determined by HPSEC-MALLS, DLS and TEM. A discussion of degradation patterns gave the detailed structural information of p -LBP. Therefore, the results from degraded fragments elucidated that the backbone of p -LBP was formed by → 4-α-Gal p A-(1 →, repeatedly. Partial region was connected by → 4-α-Gal p A-(1 → and → 2-α-Rha p -(1 →, alternatively. On the C-4 of partial → 2-α-Rha p -(1 → residues existed branches forming by → 4-β-Gal p -(1 →, → 3-β-Gal p -(1 → or → 5-α-Ara f -(1 →, while on the C-6 of partial → 3-β-Gal p -(1 → residues existed secondary branches forming by terminal-α-Ara f , terminal-β-Gal p or → 3-α-Ara f -(1 →. [ABSTRACT FROM AUTHOR]

In this study, an efficient drying process of Lycium barbarum L. polysaccharide (LBP) suitable for industrial production was developed and optimized. Three drying methods, including hot air drying (40–80 °C), vacuum drying (40–60 °C) and spray drying were test and compared. Hot air drying and vacuum drying cost long time and produced a brown product which needs further process due to the agglomeration or alveolation form. The condition of spray drying (without any excipient) was optimized by orthogonal experiment, which gave different optimum conditions based on LBP recovery rate (LBP solution concentration 1.06 g/mL, inlet air temperature 170 °C, sample flow rate 15 mL/min and air speed 4.2 m 3 /min) or LBP transparency (LBP solution concentration 1.04 g/mL, inlet air temperature 170 °C, sample flow rate 20 mL/min and air speed 2.8 m 3 /min). Pilot scale experiments showed preferable stability of LBP product quality and process parameters. Sample of spray drying (SD) had the highest scavenging free radical effects, the best appearance (LBP transparency), and uniform morphology with hollow sphere which are important properties for the reconstitution of the powder product. Considering the product appearance and product activity, the spray drying was selected to apply in industrial production. [ABSTRACT FROM AUTHOR]

The antidiabetic effect and potential mechanisms of the polysaccharides from the fruits of Lycium barbarum L. (LBPs) by the mouse model of high-fat diet/streptozotocin-induced diabetes were investigated. Six-week oral administration of LBPs (200 mg/kg/day) resulted in improvement in the levels of fasting blood glucose (13.51% decrease) and glycated hemoglobin and β-cell function in diabetic mice, and simultaneously induced a 3.3-fold increment in one taxon belonging to genus Allobaculum in gut bacterial community. The experiments of fecal microbiota transplantation and antibiotics treatment confirmed that the LBPs-mediated gut microbiota participated in the glycemic control of the diabetes management. Moreover, LBPs intervention guarded the intestinal barrier function via upregulating the expression of zonula occludens 1 both in vivo (analyzing the gut permeability in diabetic mice) and in vitro (using intestinal-like Caco-2/RAW264.7 cells co-culture inflammation model). Collectively, our study showed that LBPs could confer anti-diabetic effect through modifying gut microbiota and intestinal barrier. [Display omitted] [ABSTRACT FROM AUTHOR]