Newborn-derived Lactiplantibacillus plantarum HLPL03: environmental tolerance and metabolism of functional oligosaccharides

Abstract:

[Objective] To analyze the probiotic functions of Lactiplantibacillus plantarum HLPL03 derived from the stool of healthy newborns and evaluate the environmental tolerance and metabolism of functional oligosaccharides of this strain. [Methods] The tolerance of L. plantarum HLPL03 to extreme conditions was evaluated by treatments with the gastrointestinal environment, hydrogen peroxide, and antibiotics. The modified media were used to evaluate the metabolism of functional oligosaccharides by L. plantarum HLPL03. Furthermore, the effects of functional oligosaccharides on the antibacterial activities, hydrophobicity, and adhesion of L. plantarum HLPL03 were investigated. [Results] The viable count was above 10⁴ CFU/mL when L. plantarum HLPL03 was cultured at pH 2.5 for 3 h and close to 10⁷ CFU/mL after the strain was cultured in 0.30% bile salt for 6 h. The viable count increased significantly when L. plantarum HLPL03 was cultured with 1.0 mmol/L H₂O₂for 6 h (P<0.001). L. plantarum HLPL03 metabolized different functional oligosaccharides (except xylooligosaccharides) and inhibited common food-borne pathogens. Raffinose was the best oligosaccharide to improve the biological activity of L. plantarum HLPL03. It enhanced the surface hydrophobicity of the strain by 36.1% and increased the adhesion rate of the strain on Caco-2 cells from 16.78% to 42.11%. [Conclusion] L. plantarum HLPL03 from healthy newborns has good resistance to environmental stress, with the biological activities effectively promoted by functional oligosaccharides such as raffinose, serving as characteristic lactic acid bacteria for research and development.

Key words:newborn;Lactiplantibacillus plantarum;tolerance;functional oligosaccharides;antibacterial;adhesion