Ultrasonic Degradation Improves the In Vitro Utilization of Oolong Tea Pectic Polysaccharides: Structure...

Area of Science:

• Food Science and Technology
• Microbiology
• Biochemistry

Background:

• Pectic polysaccharides from tea residues are valuable prebiotic dietary fibers.
• Oolong tea polysaccharides (FCTP) show potential as prebiotics.
• Optimizing FCTP extraction and modification is key for enhanced probiotic utilization.

Purpose of the Study:

• To optimize FCTP extraction from Oolong tea (Camellia sinensis 'Foshou').
• To investigate structural changes in FCTP after ultrasonic degradation.
• To evaluate the in vitro prebiotic potential of modified FCTP using Lactobacillus salivarius BXP5.

Main Methods:

• Enzyme-assisted extraction for FCTP yield optimization.
• Ultrasonic treatment to modify FCTP structure and molecular weight.
• Fourier-transform infrared spectroscopy (FTIR), methylation, and nuclear magnetic resonance (NMR) for structural analysis.
• In vitro fermentation assays with L. salivarius BXP5.
• Non-targeted metabolomics and proteomics for mechanistic insights.

Main Results:

• Enzyme-assisted extraction yielded 11.10% FCTP, higher than conventional methods.
• Ultrasonic treatment reduced FCTP molecular weight, increased uronic acid content, and altered its structure to be more accessible.
• Ultrasonically degraded FCTP (uFCTP) significantly enhanced L. salivarius BXP5 proliferation compared to native FCTP.
• uFCTP modulated nucleotide and carbon metabolism, and ribosomal biogenesis in L. salivarius BXP5.
• Key metabolites and proteins correlated with enhanced probiotic growth and carbohydrate utilization were identified.

Conclusions:

• Ultrasonic degradation is an effective strategy to modify tea-derived pectic polysaccharides.
• Modified FCTP exhibits improved prebiotic activity, enhancing probiotic L. salivarius BXP5 utilization.
• Tailoring polysaccharide structure through physical methods can optimize prebiotic functionality and host-microbe interactions.