Study On Extracting And Bacteriostatic Effects Of Volatile Composition Of Dendrobium Officinale

Dendrobium officinale Kimura et Migo as a kind of natural medicinal and edible food,have good health care function,therefore,more and more people concern about it.At home and abroad,there are a lot of study on the chemical composition and the efficacy of Dendrobium officinale,but the researches on Dendrobium officinale's bacteriostatic composition are rare.Therefore,this paper chosed the dried Dendrobium officinale from Yunan?dried Dendrobium officinale?as raw material,studied the extraction technologies of Simultaneous Distillation-Extraction Method and Soxhlet Extraction Method of Dendrobium officinale,used GC-MS to analysis the volatile composition of Dendrobium officinale on Simultaneous Distillation-Extraction Method and analysis Dendrobium officinale crude extract on Soxhlet Extraction Method.Then,this paper took the bacteriostatic experiments on volatile composition of Dendrobium officinale and Dendrobium officinale crude extract of two extraction technologies,so as to explore and analyze the bacteriostatic effects of volatile composition of Dendrobium officinale,in order to provide scientific evidence and technical support for developing Dendrobium officinale resources.The main results were as follows:1.The study on the extraction technologies of the volatile composition of Dendrobium officinaleThis paper selected Simultaneous Distillation-Extraction Method to extract the volatile composition of Dendrobium officinale,used Soxhlet Extraction Method to extract Dendrobium officinale crude extract as a contrast test.This paper took water-bath temperature,solid-liquid rate,extraction time as reference factors,designed single factor test and L₉?3⁴?orthogonal test.The result of Simultaneous Distillation-Extraction Method shows that its'optimized technological condition is water bath temperature 50?,solid-liquid rate1:25g/mL,and extraction time 3.5h.The extraction rate of volatile composition of Dendrobium officinale is 1.63%.The Order of the influence of various factors is extraction time>solid-liquid rate>water bath temperature.The result of optimized technological conditions of Soxhlet Extraction Method is water bath temperature 45?,solid-liquid rate1:45g/mL and extraction time 4h.The extraction rate of Dendrobium officinale crude extract is 3.98%.In terms of the influence of extraction,the order of three factors is extraction time>water bath temperature>solid-liquid rate.2.Analysis on GC-MS of chemical composition of the volatile composition of Dendrobium officinaleThis paper used GC-MS to analyze the volatile composition of Dendrobium officinale on Simultaneous Distillation-Extraction Method,and Dendrobium officinale crude extract on Soxhlet Extraction Method.The result shows there are identified 51 compounds of the volatile composition of Dendrobium officinale on Simultaneous Distillation-Extraction Method,which main composition include:phytosterol?21.79%?,2,6-BHT?10.13%?,stigmasterol?8.57%?,vitamin E?8.38%?,eugenol?6.46%?,tocopherylacetate?5.26%?and campesterol?4.89%?,?E?-2-hexenal?2.98%?,linalool?1.95%?,terpineol?1.92%?,phenol?0.32%?.There are identified 44 compounds of Dendrobium officinale crude extract on Soxhlet Extraction Method.Its'main composition are Dibutyl phthalate?53.01%?,phytosterol?20.20%?,2,6-BHT?13.09%?,azulene?2.41%?,eugenol?1.21%?.And analyzed the main kinds and relative content of compositions of Dendrobium officinale extract of the two extraction technologies.3.Bacteriostatic effects of the volatile composition of Dendrobium officinale and analysis its'bacteriostatic compositionThis paper chosed four of the most common pathogenic bacterium as the test of bacterium,they are gram-positive bacterium:Staphylococcus aureus,gram-negative bacterium:Escherichia coliFigure,Salmonella typhimurium and Enterobacter sakazakii.This paper adopted filter paper method,according to the bacteriostatic circle diamete,it can be concluded that the bacteriostatic effects of four kinds of bacterium of the volatile composition of Dendrobium officinale and its'crude extract of two methods respectively.The result shows that the order of bacteriostatic effects of four kinds of bacterium of the volatile composition of Dendrobium officinale on Simultaneous Distillation-Extraction Method and the order of bacteriostatic effects of four kinds of bacterium Dendrobium officinale crude extract on Soxhlet Extraction Method is Staphylococcus aureus>Enterobacter sakazakii>Escherichia coli>Salmonella typhimurium.This paper used double dilution method to measure the minimal inhibition concentration of four bacterium of Dendrobium officinale extract on two extraction technologies.The result shows that the MIC of the volatile composition of Dendrobium officinale and its'crude extract of two extraction methods of Escherichia coliFigure,Salmonella typhimurium,Enterobacter sakazakii,and Staphylococcus aureus are 10mg/mL,10mg/mL,5mg/mL and 2.5mg/mL respectively.The minimum MIC is Staphylococcus aureus.The bacteriostatic effects of the volatile composition of Dendrobium officinale onSimultaneous Distillation-Extraction Method are stronger than the bacteriostatic effects of Soxhlet Extraction Method.Bacteriostatic effects to gram-positive bacterium of volatile composition of Dendrobium officinale and its'crude extract stronger than bacteriostatic effects to Gram-negative bacterium.Through the test results,it is concluded that the possible bacteriostatic compositions of volatile composition of Dendrobium officinale and its'crude extract of two extraction method are phytosterol,eugenol,2,6-BHT,terpineol,linalool,?E?-2-hexenal and phenol.