Abstract:

Objective: To optimize the extraction processing of antibacterial substances from Jasminum nudiflorum Lindl flowers. Methods: On the basis of antibacterial activity as an index, orthogonal experiments were used to investigate the effects of solvent concentration, extraction temperature and extraction time on extraction rate of antibacterial substances from Jasminum nudiflorum Lindl flowers. Results: The optimal extraction conditions were 90% ethanol, extraction temperature of 60 ℃ and extraction time of 2 h. The extract from Jasminum nudiflorum Lindl flowers had the minimum inhibitory concentration of 0.125g/mL and the minimum bactericidal concentration of 0.25 g/mL for Staphylococlus aureus, Sarcina lutea, Bacillus subitilis, Proteusbacillus vulgaris and Escheichia coli. Strong acid and heating treatments of the extract could result in the loss of antibacterial effect. On the other hand, antibacterial activity of the extract was not affected by UV, oxidants and reductants in alkaline environments. Antibacterial substances were existed in ethyl acetate and n-butanol phase during extraction process. Conclusion: The extraction processing in this study is feasible to extract bioactive substances with antibacterial activity from Jasminum nudiflorum Lindl flowers.

Key words: flower of Jasminum nudiflorum Lindl, extract, bacteriostatic activity