| Propolis (bee glue) is a resinous or sometimes wax-like bee hive product collected by honeybees from buds and leaves of plants, mixed with pollen as well as enzymes secreted by bees. It has been used by man since ancient for its pharmaceutical properties. It is still used as remedy in folk medicine. Research shows it possesses antiseptic, antibacterial, antifungal, antiinflammatory, hepatoprotective and antitumor et al. properties. The chemical constituent of propolis is very complex, more than 300 compounds had been detected in it, such as polyphenols, terpenoids, steroids, sugars and amino acids, et al.. Among them, the volatile compounds are great important due to their potent biological activities. In general, crude propolis contains 10% volatile oils and their chemical constituents are relatively complex, too. But there is little literature about volatile of Chinese propolis.China has diverse vegetation and original plants of propolis. So the chemical constituents of Chinese propolis are complex and different with propolis from other place. To understand the properties of Chinese propolis and analysis their chemical compositions, antioxidant and antimicrobial activity systematically, it is meaningful to collected propolis from different areas of China and study them.1 To study the volatile components in propolis collected in Inner Mongolia and get the optimized sampling method, we extracted the volatile components in the propolis by three methods, traditional hydrodistillation (HD), simultaneous distillation extraction (SDE) and dynamic headspace sampling (DHS), and analyzed the components by GC/MS. By searching the database, we got high similarity results with the reported compounds. The relative content of the components were calculated by peak area normalization method.12 kinds of volatile components can be measured by HD-GC/MS. The major components are 3-methyl-2-buten-l-ol (26.81%), phenylethyl alcohol (17.06%), eudesmol (14.53%),2-methoxy-4-vinylphenol (9.47%), a-bisabolol (4.29%).40 kinds of volatile components are identified by SDE-GC/MS. The main of them are a-bisabolol (20.19%), 2-methyl-3-buten-2-ol(10.76%),3-methyl-2-buten-l-ol (8.28%), azulene (5.21).70 kinds of volatile components are identified by DHS-GC/MS. The main of them are heptadecane (6.96%), phennathrene (3.99%), ar-tumerone (3.80%), 1-(1,5-dimethyl-4-hexenyl)-4-methyl-benzene (3.14%), octadecane (3.23%), 1-(1,5-dimethyl-4-hexenyl)-4-methyl-benzene (3.14%), hexadecane (2.47%). Among the three methods, the most volatile components can be detected by DHS. It is the best way to analytic, but the volatile components can not be obtained for further biological activity experiment. For that reason, SDE is the best way.2. The volatile components of 23 propolis samples from 17 provinces of China were analyzed by dynamic headspace sampling with gas chromatography and mass spectrometry (DHS-GC-MS). Eighty-four volatile components were identified from the propolis samples, includes sesquiterpenoids (13), monoterpenoids (2), phenolic and alcohols (19), aldehydes and ketones (12), organic acids and esters (12), hydrocarbons(12) and various other substances(14). The major components wereα-cedrene (0.08-8.12μg/μL),γ-eudesmol (0.04-4.33μg/μL),3-methyl-3-buten-l-ol (0.42-24.74μg/μL),α-terpineol (0.02-1.31μg/μL), acetic acid (2.23-21.99μg/μL), benzyl dehyde(0.13-10.23μg/μL), benzyl alcohol (0.01-7.65μg/μL), cedrol (0.03-0.90μg/μL), butanoic acid, ethyl ester (0.10-4.64μg/μL), y-cadinene (0.05-2.58μg/μL), phenylethyl alcohol (0.02-5.60μg/μL) and styrene (0.06-5.81μg/μL), et al.. The samples were subjected to principal component analysis (PCA) and hierarchical cluster analysis (CA) according to the composition corresponding essential oils in order to model their pattern. Different significant relationship was found between volatile composition and climatic characteristics and colors of the 23 populations, differences in the subtropical and temperate zones of samples from different samples, but nearly no significant relationship on volatile composition and propolis colors.3. The volatile components of 25 propolis samples from 18 provinces of China were analyzed by steam-distillation extraction with gas chromatography and mass spectrometry (SDE-GC-MS).406 volatile components were identified from the propolis samples, includes sesquiterpenoids (94), monoterpenoids (30), phenolic and alcohols (31), aldehydes and ketones (56), organic acids and esters (90), hydrocarbons (81) and various other substances (24). The major components were guaiol (0.56-13.61%), benzaldehyde (0.07-8%), benzyl alcohol (0.08-17.67%), cedrol (0.48-37.46%),γ-eudesmol (1.81-21.48%), benzeneethanol (0.03-14.43%), 2-methoxy-4-vinylphenol(0.31-14.06%), a-curcumene (0.23-5.9%), benzyl benzoate (0.06-6.59%), acetophenone (0.08-2.05%),4-ethenyl-1,2-dimethoxy-benzene (0.31-14.06%), nonanal (0.1-1.48%), a-cedrene (0.05-1.98%),β-eudesmol (6.1-27.89%). The samples were subjected to principal component analysis (PCA) and hierarchical cluster analysis (CA) according to the composition corresponding essential oils in order to model their pattern. The results obtanined, differences in the tropical, subtropical and temperate zones of samples from different samples, but maybe have no significant relationship about propolis colors.4. Reducing power was utilized to examined the total antioxidant activity of propolis extracts, and DPPH (1,1-diphenyl-2-picrylhydrazyl) was used to determined the free radical scavenging ability. Antioxidant activity varied with different samples. Reducing power of all samples are from 0.0102 to 0.0649. AAI (Antioxidant activity index) are from 0.19 to 2.533. Shandong propolis exhibited greatest reducing power and strongest free radical scavenging effect. All samples have been compared by the climatic characteristics and propolis colors, temperate zones or yellow propolis have stronger reducing power and free radical scavenging effect.5. The agar diffusion method using filter paper disks was employed. Antibacterial activity was measured by measure diameters of inhibition zones. The minimum inhibitory concentration (MIC) values obtained using the microdilution broth susceptibility assay. Propolis samples exhibited significant antibacterial and antifungal activities, affecting a wider apectrum of microorganisms and presenting lower or no activity against several bacterial and fungal.In contrast, the propolis samples are different in type and content of the chemical compositions. The differences manifest suggest to the volatile chemical composition in relation to different climates and original plants. The experiment demonstrated that the content of volatile oils in Chinese propolis was abundance, and it showed to process antioxidant activity and antimicrobial activity. It could been predicted that propolis is useful as a natural antioxidant and antimicrobial agents in medicine, chemical engineering and food industry.
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