| Propolis has been attracted much attention in recent years as an useful substance applied in medicine, it possessed various biological activities, such as antioxidant, antibacterial, antiinflammatory, antitumor and so on. And these activities were strongly related to the complex chemical composition, thus it had high value to investigate the chemical composition and biological activities of propolis to the academic field. On account of China comprehended large areas, which crossed from tropical and sub-tropical to temperate zones, the characteristics of propolis were extremely diverse. The influences of the season and geographic area to propolis were always the emphasis on propolis research, thus we worked on the influences of the season and geographic area to Chinese propolis.Our work was focused on the investigation of the Chemical composition, antioxidant activity and antimicrobial activity against 9 microbe strains of Chinese different season propolis from tropical, sub-tropical and temperate zones, for the purpose of getting the message of the influence factors on Chinese propolis and establishing foundation of Chinese propolis researches. Spectrophotography was used to determine color intensity, E1cm 1% , total phenol, total flavonoids, flavone-flavonol and flavanone of ethanolic extract of propolis (EEP), HPLC method was used and then we analyzed the similarity of EEP; prussian blue spectrophotometry was used to examine total antioxidant activity, and DPPH was utilized to evalue its free radical scavenging activity. Antimicrobial activity was tested against three Gram positive bacterias (Staphilococcus aureu, Bacillus subtilis, Clostridium perfringens), two Gram negative bacterias (Escherichia col, proteusbacillus vulgaris) and four fungus cultures (Penicillium glaucum, Aspergillus niger, Mucor racemosu, Rhizopus nigricans), and was investigated by the determination of inhibition zones and MIC of EEP.Antimicrobial activities of EEP of 29 propolis from 20 provinces of China were also researched by the means of determining the inhibition zones and MIC of EEP. It would helpful for deeply and widely analyzing Chinese propolis.Results were as followed.1. There was significant difference with regards to the seasonal effect on the chemical components of EEP, the contents of total phenol, total flavonoids, flavone-flavonol and flavanone reached maximum percentage in June and July, minimum in September, moreover, the disparity in the contents of total phenol and total flavonoids of EEP from different months was strongly significant. The maximum value of total phenol and total flavonoids contents were 243.87±152.13 mg/g and 189.34±107.51 mg/g respectively, the minimum of them were 187.25±146.45 mg/g and 122±81.02 mg/g respectively. The content of flavone-flavonol and flavanone seemed to be change a little with the change of season.The geographic area significantly influenced the chemical components of EEP, too. The contents of total phenol, total flavonoids and flavone-flavonol of tropical zone propolis were significant different with the contents of sub-tropical and temperate zones, especially total phenol and total flavonoids contents, the contents of them in tropical zone propolis were 1/6～1/4 of them in sub-tropical and temperate zones. The correlation between E1cm 1% and total flavonoids was significant.2. Prussian blue spectrophotometry was utilized to examine the total antioxidant activity of EEP from different seasons and areas, and DPPH was used to determine the free radical scavenging ability. The results showed that the geographic area significantly influenced the antioxidant activity. The total antioxidant activity of tropical zone propolis was the weakest, it ranged from 0.32～0.51, sub-tropical zone propolis had strong total antioxidant activity, and ranged from 1.33～1.48, and temperate zones propolis had the best total antioxidant activity, ranged from 2.28～2.62, the free radical scavenging activity of EEP had the same tendency with the total antioxidant activity, tropical zone propolis had the weakest free radical scavenging activity, AAI values were less than 0.5, and AAI value of sub-tropical zone propolis ranged from 1.87～2.47, and temperate zones propolis had the best free radical scavenging activity, AAI value ranged from 4.61-6.29. In a word, that the propolis from the tropical zone of China had the weakest antioxidant activity, the antioxidant activity of sub-tropical zone propolis of China was better than the tropical zone, and temperate zones propolis had the best antioxidant activity. There was also significant difference with regards to the seasonal effect on the antioxidant activity, moreover, the correlation among E1cm 1% , total flavonoids, flavone-flavonol and the free radical scavenging activity were significant.3. The antimicrobial activities against 9 microbe strains of EEP from different seasons and geographic areas were researched by the means of determining of inhibition zones and MIC of EEP. The results of the associativity between the inhibition zones and MIC of EEP showed strong negative correlation between them, which means the bigger inhibition zones, the smaller MIC, and betters the antimicrobial activity. Then we analyzed the influence of season on the antimicrobial activity, and found there had no different among the antimicrobial activity of different seasons propolis.The geographic area significantly influenced the antimicrobial activity against Gram positive, the antimicrobial activity against Gram positive bacteria of temperate zone EEP was the best, sub-tropical zone EEP was weaker than the temperate zone and tropical zones EEP had the weakest antimicrobial activity, it had the same tendency with the contents of chemical components, but the associativity between the antimicrobial activity and the chemical components contents is not good. The geographic area didn't significantly influenced the antimicrobial activity against Gram negative bacteria and fungus culture, but fungus culture were shown to be more sensitive to tropical zone EEP than Gram positive bacteria and Gram negative bacteria, the antimicrobial activity of it was almost equal with the antimicrobial activity against fungus culture of sub-tropical zone and temperate zone EEP.4. The chemical composition of EEP from different seasons and geographic areas were detected by HPLC. The similarity was analyzed, and we found that the chemical composition of tropical zone EEP was much different with the other area EEP, the sub-tropical zone EEP had the similar chemical composition with temperate zone EEP, the season significantly influenced the chemical composition of tropical zone EEP, but not for the sub-tropical zone and temperate zone EEP.5. The antimicrobial activities of EEP of 29 propolis from 20 provinces of China were also researched by the means of determining the inhibition zones and MIC of EEP, we classified the propolis according to the climate areas, the results showed that fungus culture, Gram positive bacteria and Gram negative bacteria were all shown to be sensitive to Chinese EEP, but the climate area didn't significantly influenced the antimicrobial activity. The average of the inhibition zones against Gram positive bacteria of EEP was 9.88±1.47 mm, The average of the inhibition zones against Gram negative bacteria was 8.75±1.56 mm, and the average of the inhibition zones against the fungus culture was 10.01±0.65 mm, so the antimicrobial activities of Chinese EEP against fungus culture was best, and weakest was against Gram negative bacteria. Moreover, EEP had the weakest antimicrobial activity against proteusbacillus vulgaris, and had the best antimicrobial activity against Rhizopus nigricans in 9 microbe strains.
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