Structural Characteristics, Antioxidant, and Immunostimulatory Activities of an Acidic Polysaccharide from Raspberry Pulp

Abstract

The extraction and characterization of new bioactive plant-derived polysaccharides with the potential for use as functional foods and medicine have attracted much attention. In the present study, A novel acidic polysaccharide (RPP-3a) with a weight-average molecular weight (Mw) of 88,997 Da was isolated from the raspberry pulp. RPP-3a was composed of rhamnose, arabinose, galactose, glucose, mannose, and galacturonic acid at a molar ratio of 13.1:28.6:16.8:1.4:6.2:33.9. Structural analysis suggested that the RPP-3a backbone was composed of repeating units of →4)-β-Galp-(1→3,4)-α-Rhap-(1→[4)-α-GalAp-(1→4)-α-GalAp-(1→]n with branches at the C-4 position of rhamnose. The side chain of RPP-3a, containing two branch levels, was comprised of α-Araf-(1→, →5)-α-Araf-(1→, →3,5)-α-Araf-(1→, →3)-β-Galp-(1→, →3,6)-β-Galp-(1→, →4)-β-Glcp-(1→, and →2,6)-α-Manp-1→ residues. RPP-3a exhibited moderate reducing power and strong hydroxyl and superoxide anion radical scavenging abilities. RPP-3a significantly promoted the viability of RAW264.7 macrophages by increasing the production of nitric oxide (NO), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β) at both the expression and transcriptional levels. In summary, the immunostimulatory and antioxidant activities make RPP-3a a viable candidate as a health-beneficial functional dietary supplement.

The Isolation, Structural Characterization and Anti-Inflammatory Potentials of Neutral Polysaccharides from the Roots of Isatis indigotica Fort.

“…The mRNA expression was measured by qPCR under the following reaction conditions: 40 cycles of PCR amplification, pre-denaturation at 95 °C for 2 min, denaturation at 95 °C for 15 s and annealing and extension at 60 °C for 30 s. By normalizing the Ct data to GAPDH expression, the comparative CT (2 −ΔΔCt ) approach was used to assess the relative gene expression. Table 3 contains a list of the primer set sequences employed for amplification [ 76 ].…”

Chemical composition, pharmacological activity and development strategies of Rubus chingii: A review

“…The homogeneous acid polysaccharide RPP-2a was composed of rhamnose-arabinose, galactose, glucose, xylose, galacturonic acid, and glucuronic acid, and the molar ratio of the above components was 15.4: 9.6: 7.6: 3.2: 9.1: 54.3: 0.8. As a potential natural immune enhancer, RPP-2a exhibits significant macrophage activation activity by increasing the production of nitric oxide, tumor necrosis factor- α , interleukin-6, and interleukin-1 β ( Yang et al, 2022 ). A novel acidic polysaccharide (RPP-3a) significantly promoted the viability of RAW264.7 macrophages by increasing the production of NO, tumor necrosis factor- α (TNF- α , interleukin-6 (IL-6), and interleukin-1 β (IL-1 β ) at the expression and transcription levels.…”

“…RPP-3a showed moderate reducing power and strong hydroxyl and superoxide anion radical scavenging ability. Immunostimulatory and antioxidant activities enable RPP-3a to be developed as a health-beneficial functional dietary supplement ( Yang et al, 2022 ). A new immature raspberry polysaccharide, pRCP ( 26 ), is an acidic heteropolysaccharide that acts as a potential prebiotic to improve gut health by regulating gut flora, colonic inflammation, and oxidative stress induced by high-fat diet (HFD) in mice alleviated with pRCP ( Luo et al, 2023 ).…”

Micronized Powder of Raspberry Pomace as a Source of Bioactive Compounds

“…Red raspberries ( Rubus idaeus L.) contain a variety of nutrients and phytochemicals important to human health [ 1 , 2 , 3 ]. Raspberry consumption is effective in reducing the levels of oxidative and inflammatory stress that promote heart morphological changes in old age, thereby preventing or delaying heart disease [ 4 ].…”