Chemical Composition And Biological Activity Of Essential Oils And Ethanol Extracts Of Three Juniperus Species

There are about 10 species of Juniperus,and three species are mainly produced in China,namely Juniperus rigida Sieb.et Zucc.、Juniperus formosana Hayata and Juniperus sibirica Burgsd.Three species of Juniperus were systematically studied.The results obtained provide a basis for the development of Juniperus germplasm resources and have important guiding significance.The main research results are as follows:1.（1）The contents of total phenolic contents（17.43±0.78 mmol equiv.GAE/g）and total contents of 10 phenolic compounds（323.84 mg/g）in J.rigida were the highest.The contents of flavonoids in J.sibirica（24.24±4.39 mmol equiv.QUE/g）were the highest,while the contents of 10 phenolic compounds（118.96 mg/g）were the lowest.（2）The contents of total phenols（17.43±0.78 mmol equiv.GAE/g）,total flavonoids（18.84±0.90 mmol equiv.QUE/g）and 10 phenolic compounds（323.84 mg/g）in wild species of J.rigida were higher than those in cultivated species.（3）In Yijun and Fugu,the total contents of 10 phenolic compounds in J.rigida female（479.15 mg/g,720.06mg/g）were higher than that in J.rigida male’s.2.（1）Among the essential oils of J.rigida,J.formosana and J.sibirica,the essential oils of J.sibirica has the most abundant compounds,and 38 compounds have been identified,of which 8 are common.（2）A total of 30 different compounds were detected in essential oils of wild and cultivated species of J.rigida,of which 27 were common components.（3）A total of 36 different compounds were detected in essential oils of J.rigida female and male in Yijun and Fugu,and 14 common components were identified.3.（1）In general,the ethanol extracts showed the higher radical scavenging capacity in DPPH,ABTS and FRAP assay than essential oils.（2）Ethanol extracts of J.rigida and J.formosana have shown strong antioxidant activity.（2）The antioxidant ability of essential oils of J.rigida wild species is stronger than that of cultivated species,however,the antioxidant ability of ethanol extracts of J.rigida cultivated species is stronger than that of wild species.（3）The antioxidant activities of essential oils and ethanol extracts of J.rigida male and female were determined,and the J.rigida male and female showed different antioxidant effects.4.（1）Both Juniperus essential oils and ethanol extracts showed bacteriostatic effects against Gram-negative bacteria and Gram-positive bacteria.（2）The inhibition zone of J.rigida,J.formosana,J.sibirica and wild and cultivated species of J.rigida were tested for their putative antibacterial activity,and the results showed that Juniperus had better bacteriostatic effect on S.typhimurium,E.coli and S.enteritidis.The half inhibition rate(EC₅₀)further showed that antibacterial effect of J.rigida was the best,and the bacteriostatic effect of cultivation of J.rigida was better than that of wild species’ s.（3）The results of inhibition zone of J.rigida male and female in Yijun and Fugu areas of Shaanxi Province showed that the J.rigida showed better bacteriostasis effect on S.aurous,E.coli and B.subtilis.In order to judge the bacteriostasis ability of J.rigida male and female more accurately,half inhibition rate(EC₅₀)experiment was carried out.The results showed that the bacteriostasis ability of J.rigida male were better than that of J.rigida female’s.5.（1）On the whole,Juniperus plants have certain inhibitory activities of acetylcholinesterase and butyrylcholinesterase.（2）J.formosana have shown better inhibitory activity of acetylcholinesterase and butyrylcholinesterase.（3）Both wild and cultivated species of J.rigida showed certain cholinesterase inhibitory activities.（3）The inhibiting effect of cholinesterase was different between J.rigida male and female in different regions.