Based on factual scientific health claims, prebiotics has gained significant importance in ever-growing food and pharmaceutical industries. The diverse nature of distinct prebiotics influences the host differently in distinguishable patterns. Functional oligosaccharides are either plant-derived or commercially prepared. Raffinose, stachyose, and verbascose are three types of raffinose family oligosaccharides (RFOs) that have been extensively used as medicine, cosmetic, and food additives. These dietary fiber fractions avert the adhesion and colonization by enteric pathogens and add nutrition metabolites for a healthy immune system. Enrichment of RFOs in healthy foods should be promoted as these oligosaccharides augment gut microecology by enhancing the health conferring microbes i.e. Bifidobacteria and Lactobacilli. RFOs influence the host’s multiorgan systems due to their physiological and physicochemical properties. For example, the fermented microbial products of such carbohydrates affect neurological processes, including memory, mood, and behavior in humans. Raffinose-type sugar uptake is thought to be a ubiquitous property of Bifidobacteria. This review paper summarizes the source of RFOs and their metabolizing entities highlighting bifidobacterial carbohydrate utilization and health benefits.

The immunomodulatory and antioxidant activities of crude polysaccharides extracted from Gynostemma pentaphyllum Makino (GPMPP) were investigated. GPMPP was composed of rhamnose, arabinose, xylose, mannose, glucose and galactose in the molar ratio of 1.39:3.76:1.00:1.64:4.98:5.88. In vivo studies showed GPMPP significantly increased the spleen and thymus indices, activated the macrophage phagocytosis and NK cells, and exhibited activity on none or Con A/LPS-stimulated splenocytes in a dose-dependent manner in C57BL/6 mice. Moreover, GPMPP elevated CD4⁺ T lymphocyte counts as well as the CD4⁺/CD8⁺ ratio dose-dependently, and it increased IL-2 level in the sera and spleen of Cy-immunosuppressed mice. Furthermore, GPMPP significantly increased the SOD, GSH-Px, T-AOC, GSH and CAT level, and decreased the MDA level. The results showed that GPMPP might play an important role in prevention of oxidative damage in immunological system. These findings indicate GPMPP has immunomodulatory activity in vivo and seems to be an effective natural immunomodulatory agent.

Antimicrobial peptides represent an emerging category of therapeutic agents with remarkable structural and functional diversity. Modified vasoactive intestinal peptide (VIP) (VIP analogue 8 with amino acid sequence “FTANYTRLRRQLAVRRYLAAILGRR”) without haemolytic activity and cytotoxicity displayed enhanced antimicrobial activities against Staphylococcus aureus (S. aureus) ATCC 25923 and Escherichia coli (E. coli) ATCC 25922 than parent VIP even in the presence of 180 mM NaCl or 50 mM MgCl₂, or in the range of pH 4–10. VIP analogue 8 was expressed as fusion protein thioredoxin (Trx)-VIP8 in E. coli BL21(DE) at a yield of 45.67 mg/L. The minimum inhibitory concentration (MIC) of the recombinant VIP analogue 8 against S. aureus ATCC 25923 and E. coli ATCC 25922 were 2 μM. These findings suggest that VIP analogue 8 is a promising candidate for application as a new and safe antimicrobial agent.