Two novel polysaccharides from Huangshui: Purification, structure, and bioactivities

Area of Science:

• Food Science and Technology
• Biochemistry
• Materials Science

Background:

• Huangshui (HS) is a traditional fermented product with potential sources of bioactive compounds.
• Polysaccharides are known for their diverse biological activities and applications.
• Understanding the structure-activity relationship of novel polysaccharides is crucial for their utilization.

Purpose of the Study:

• To purify and characterize two novel polysaccharides, HSP-0 M and HSP-0.1 M, from Huangshui (HS).
• To investigate the structural properties, including molecular weight, monosaccharide composition, and linkage analysis.
• To evaluate the bioactivities, specifically cryoprotective effects on Lactococcus lactis and antioxidant properties.

Main Methods:

• Polysaccharide purification from Huangshui (HS) using chromatographic techniques.
• Structural characterization involving molecular weight determination, monosaccharide analysis (GC-MS), and methylation/2D NMR spectroscopy.
• Bioactivity assays including freeze-drying tolerance tests for Lactococcus lactis and DPPH radical scavenging assays for antioxidant activity.

Main Results:

• HSP-0 M (493.87 kDa) comprised arabinose, galactose, glucose, xylose, and mannose, with a primary chain of T-Glcp-(1→4)-Glcp-(1→2)-Glcp-(1→3)-Glcp.
• HSP-0.1 M (157.6 kDa) contained fructose, arabinose, galactose, glucose, xylose, mannose, ribose, galacturonic acid, and glucuronic acid, with a complex backbone structure.
• HSP-0 M protected Lactococcus lactis during low-temperature and freeze-drying processes, while HSP-0.1 M exhibited significant antioxidant activity.

Conclusions:

• The distinct structural features of HSP-0 M and HSP-0.1 M correlate with their observed bioactivities.
• HSP-0 M demonstrates potential as a cryoprotective agent for probiotics and other sensitive biomolecules.
• HSP-0.1 M shows promise as a natural antioxidant, with potential applications in food, cosmetics, and pharmaceuticals.