Abstract:
The main goal of this investigation is to determine the main flavonoid which is the main activity of Thai propolis by using spectrophotometric method and high-performance liquid chromatography (HPLC). Additionally, the antioxidant and antimicrobial activity of the propolis from different location in China, Korea and Northern Thailand are also determinated. The result shows that the total flavonoids in all 17 propolis from the different geographic locationin Thailand are lower than 2% and lower than the propolis samples from UK, Korea, Brazil and China. However, one sample (CM1) from Chiang Mai province of Thailand is higher (13.34%) and closer to the other countries. The contents of 8 major flavonoids in Thailand propolis are as follows:rutin ranges (w/w) 0.01–0. 28%, myricetin 0.00–0.08%, quercetin 0.00–0.92%, kaempferol 0.00–0.36% , apigenin 0.00–0.25%, pinocembrine 0.00–0.09%, chrysin 0.00–1.81% and galangin 0.00–1.81%. Only one propolis sample ( CM1 ) from Chiang Maiidentified all 8 main flavonoids, rutin(0.06%), myricetin (0.08%), quercetin (0.92%), kaempferol (0.36%), apigenin (0.25%), pinocembrine (0.01%), chrysin (1.81%) and galangin (1.81%), and had many peaks in the HPLC figure.The antioxidant activity test showed that propolis had a strong reducing power and strong DPPH radical scavenging activity, indicating that the antioxidant activity of the propolis samples from Chiang Mai (CM), Chinag Rai (CR), Lamphun (LP) and Nan (N) of Thailand were all good. The result of study on MIC50 from various propolis extracts against Staphylococcus aureus. demonstrates that all the propolis extracts show the antimicrobial effect to Staphylococcus aureus, the sequence from low to high of MIC50 against S.aureus is Brazil<N4<N2<CR1<N1<CR-MFU<CR7<CR3<CR4<CM3<LP. For the antimicrobial activity against Candida albicans,among the 11 kinds of propolis samples, only three kinds of propolis, Brazil, Chiang Rai (CR4), and Nan4 (N4), show a weak antimicrobial activity against Candida albicans.