| Myrica rubra Sieb.et Zucc belongs to the branch of Myrica, genus of Myrica. It is widely distributed in Zhejiang, Jiangsu, Fujian. Jiangxi, Hunan and Guangdong province of China. The people in the Bijie, Shuicheng of Guizhou province who belong to nationality of Wu, Buyi and Miao not only has been used the root, stem, fruit of Myrica nana Ceval to cure enteritis, hemoslasia, arthralgia, but also use the leaf to cure scald, carbuncle and bellyache etc. The leaf of Myrica rubra Sieb.et Zucc contains high content of phenolic compound, which mainly consists of flavonoid and proanthocyanin. Both of the two kinds of compounds have apparent bioactive activity. In order to probe into the bioactive activity of the leaf and its application, this paper focuses on the optimum extraction technology of flavonoid from Myrica rubra leaf and the antimicrobial property of the extraction. It would serve as a basis for the development and utilization of Chinese traditional medicine. The main results were as follows:1. The extraction of antimicrobial compound from Myrica rubra leaf and the antimicrobial property including temperature and pH influence to the leaf extraction was investigated. The result showed that the leaf extraction had obvious antimicrobial actions especially to Gram + bacteria such as Staphylococcus aureus and Bacillus subtilis. It is not very effective to Gram "such as Escherichia coli. As for the common spoiage mould including Penicilium citainum and Aspcrgillus niger, it is also very effective. The minimai inhibition concentration (MIC) was as follows: Escherichia coli 5%, Bacillus subtilis 2.5%, Staphy lococcus aureus 1.25%, Penicilium citainum 2.5%, Pcnicillium cyclopium 1.25%, Aspcrgillus niger 1.25%. And it was proved that the more the concentration of the extraction, the more the antimicrobial activity it has. It was also proved that the extraction has very good temperature stability and it can be effective from pH 5-9. Besides, the addition of sugar or salt can improve the antimicrobial activity. The antimicrobial of extraction by different solvent is quite different. 60% ethanol gave the best results followed by 95% ethanol > aether > ethyl acetate > n-butanol> acetone > 30 % ethanol > distilled water. The antimicrobial effect of the leaf extraction is a little weaker than common antimicrobial sodium such as benzoate and Potassium Sorbic Acid. In the same action time, the higher the concentration of the extraction, the higher of the inhibition rate is. With the same concentration of extraction, the longer the action time will bring higher inhibition rate.2. The optimum extracting condition of flavonoids from Myrica ruba /caf were studied in this article. With the assistance of ultrasonic treatment, we use ethanol to soak the myrica ruba leaf and distill the flavonoid. And the main factors which effect the distill rate were also discussed. The result from Lg (34) table shows that 45:1 of 40% ethanol to douse the dried Myrica ruba leaf for 24 hours, ultrasonic treatment lasts for 45 min twice. The extraction average rate was as high as 99.30%. The content of flavonoid in the extraction liquid was as high as 8.16%3. The flavonoid and phenol content of the leaf extraction of four seasons (May, July, Sept. and Dec.) were mensuratcd and the antimicrobial ability to bacterial and mould was studied. Obvious difference is found between the bioactive compound and antimicrobial ability. The leaf of Sept. has the highest content of phenol and flavonoid at 22.6% and 11.5% respectively. And the leaf of Dec. is the lowest at 11.2% and 5.3% respectively. And all four season's extraction has good antimicrobial ability. The inhibition rate to bacterial ranges from 41.5% to 72.3% and vhe inhibition rate to mould ranges from 48.6% to 79.5%. The antimicrobial activity has some connection with the phenol and flavonoid content.4. Using liquid-liquid extraction, the ethanolic extraction was subsequently fractionated into four parts: petroleum ether ( I ), carbon tetrachloride( I... |
PDF Full Text Request