Abstract:Lonicera japonica, obtained from Shandong and Guangdong, was used as the raw material in this study. The volatile oil was separated by CO2 supercritical fluid extraction, and afterwards the water-soluble and the water-insoluble subfraction were prepared from the residue after volatile oil isolation. The chemical composition of volatile oil was analyzed by GC-MS and high performance liquid chromatography was used to determine the content of chlorogenic acid and galuteolin in residue extract of Lonicera japonica. The anti-bacterial activities of volatile oil and extract were investigated by disk diffusion assay and minimum inhibitory concentration (MIC). The main components of Lonicera japonica volatile oil were fumaronitrile (61.5%) and amyl acetate (37.7%), and the content of lorogenic acid and galuteolin in water-soluble residue extract from Shandong province was the highest among the 4 residue extracts. The Lonicera japonica volatile oil and subfractions of ethanol extract exhibited different inhibitory effects on the six pathogens. The antimicrobial effect of the two extracts on gram-positive bacteria was better than that of gram-negative bacteria. The antibacterial effect of the volatile oil in Lonicera japonica from Shandong was the strongest with the MIC of 64 μL/mL and the diameter of inhibition zone of 9.3 mm. Meanwhile, the water-soluble subfraction of Lonicera japonica from Guangdong showed a significantly high antibacterial effect on bacillus subtilis with the diameter of inhibition zones above 15mm and MIC value of 16 μL/mL. There was no significant difference in the antibacterial activity of the extract in Lonicera japonica from Guangdong and Shandong.
