Abstract:

In this study, the antimicrobial activity of physalins from Calyx seu Fructus Physalis (persistent calyx of Physalisalkekengi L. var. franchetii (Mast.) Makino) against several common spoilage and pathogenic microbes as a function oftemperature, pH, visible light and ultraviolet (UV) was investigated. The physalins significantly inhibited gram-positivebacteria and showed an inhibitory effect on some of the molds tested but had no inhibitory effect on yeast. The minimuminhibitory concentrations (MIC) against Staphylococcus aureus and Byssochlamys fulva were 31.3 and 62.5 μg/mL,respectively. The antimicrobial stability of the physalins was most significantly by pH, followed by temperature, but onlymarginally by visible light and UV illumination. The strongest antimicrobial activity was observed at 20－35 ℃ and affectedonly slightly at higher temperatures. The antimicrobial activity of the physalins was stable under acidic, neutral and weakalkaline conditions, but promptly damaged under strong alkali condition.

Key words: persistent calyx of Physalis alkekengi L. var. franchetii (Mast.) Makino, physalin, antibacterial properties, stability