Study On Antibacterial Activity Of Lavender Angustifolia

Objective In order to explore an efficient,low toxic and environmentally friendly plant source antibacterial agent,the extracts of lavender stem and leaf planting in Heilongjiang Jiamusi region should be taken as a substitute for traditional chemical pesticides to control the diseases caused by fungus in fruit and vegetable products.The optimum extraction conditions of the composition in lavender stem and leaf have been discussed.The chemical compositions of the extracts extracted from the lavender stem and leaf were analyzed with gas chromatography-mass spectrometry?GC-MS?.The antibacterial activity of the extracts of lavender stem and leaf were studied,which could provide the basic experimental data and theoretical support for the development of medicinal value and practical value of lavender stem and leaf.Methods According to orthogonal test,the optimal extraction conditions of the components of lavender stem and leaf were optimized.The chemical structure and content of the various components of the extracts extracted from the lavender stem and leaf were determined using GC-MS technique obtained by soxhlet extraction.In accordance with the double dilution method and growth rate method,the antibacterial activity of the extracts of lavender stem and leaf were authenticated,and its minimal inhibitory concentration?MIC?were calculated,which have been compared with that of dimethyl fumarate,dehydroacetic acid sodium,chlorothalonil,eugenol and guaiacol.The antimicrobial stability of the extracts of lavender stem and leaf were studied,in which the influence of different temperature,pH value,ultraviolet ray exposure time and storage time on the inhibition of plant pathogens were also studied.Results Extraction yield of the components of lavender stem and leaf was the highest by the ultrasonic assisted ethanol solution method.The best extraction condition were that the volume fraction of ethanol solution,the solid liquid ratio(g?mL^-1),operation time and temperature of ultrasonic cleaning machine were 70%,1:15,40 min and 60?C,respectively.There were 34 species components with the highest matching coefficient in the extracts of lavender stem and leaf,accounting for 94.24%of the total content.The main components were linalool?16.66%?,linalyl acetate?12.01%?,endo-Borneol?8.67%?,caryophyllene oxide?7.72%?and tau-Cadinol?5.61%?.It can be seen through antibacterial test,the extracts of lavender stem and leaf had antibacterial activity on Colletotrichum Capsici,Phytophthora Capsici Leonian,Fusarium Oxysporum.f.sp.Cucmrium,Botrytis Cinerea Pers.,Phomopsis Vexans?Sacc.Et Syd.?Harter.and Phytophthora Infestans.The bactericidal capacity of lavender stem and leaf were lower than that of dimethyl fumarate,dehydroacetic acid sodium and chlorothalonil,but compared to eugenol and guaiacol,it was higher.Antibacterial stability of the extracts of lavender stem and leaf had been studied.The results showed that the inhibitory action of the extracts of lavender stem and leaf on indicative pathogen had no significant changes under certain conditions such as different temperature,pH value,ultraviolet ray exposure time,and storage time,but had a certain effect on the antibacterial stability of the extracts of lavender stem and leaf by a change of ultraviolet ray exposure time and pH value.Conclusions The lavender stem and leaf planted in Heilongjiang Jiamusi region are used as experimental material in this study.The antibacterial activity of the extracts of lavender stem and leaf have been proved on six kinds of phytopathogen.And it is expected to be a new,harmless and environmentally friendly plant source antibacterial agent to replace the highly toxic and highly residual traditional chemical pesticides.In combination with its antibacterial activity,its antiseptic and fresh effect could be developed subsequently to meet the demand of people's real life.And it has certain reference value for its future using in the antisepsis and preservation on fruit and vegetable products.The guidance for further development and deep processing are provided.