Biodegradation Of Cinnamon Oil And Its Products Analysis

Natural benzaldehyde is an important spice because of its superior quality and wide application, but the yield of natural benzaldehyde was so low that it couldn't meet market demand. New technique of producing natural benzaldehyde has become research hotspots. Recently, preparing spice with biotechnology has been drawn more and more attention of researchers. Guangxi province is rich in cinnamon resource, so studies on biodegradation of cinnamon oil into natural benzaldehyde have important significance.In this thesis, analytical methods by high performance liquid chromatography and UV spectrophotometry were established, which can be used for products detecting in the system of biodegradation of cinnamon oil. Using cinnamaldehyde or cinnamic acid as precursors, experiments of screening biodegradable strains were taken at the same time. The results we got are:(1) A simultaneous quantitative analytical method of cinnamaldehyde, cinnamic acid, benzaldehyde and benzoic acid in biodegradation mixture system was set up by HPLC. The best chromatographic conditions were methanol-water-acetic acid (55:45:0.05) as the mobile phase, and the UV detection wavelength was 246nm. In addition, the method is validated by accuracy and recovery experiments. The results showed that the method was accurate and reliable and it can be used for process monitor of cinnamaldehyde or cinnamic acid's biodegradation. (2) The UV-absorption characteristics of benzaldehyde and benzoic acid were studied. It was proved that the absorption value of benzaldehyde, benzoic acid and the mixture were always related to their total concentration at the wavelength of 234nm with ethanol as solvent, and the linear relation between total absorption and concentration was found. With these UV-absorption characteristics, the simple, fast quantitative analysis method was established. This method has important theoretical research meaning and higher practical value.(3) According to different geology and different climate, many soil samples were collected. The experiments of strains' separation and biodegradable strains' screen were taken. One higher transformation ability strain was taken to cinnamaldehyde's biodegradation experiment and the transformation conditions were optimized.(4) A filamentous fungus strain named Mucor sp JX23 which can transformed cinnamic acid into acetophenone with high efficiency and selectivity was isolated from soil sample. The optimization conditions' experiments were taken. The results showed that the highest yield can reach 3.6g/L of acetophenone when concentration of cinnamic acid was 5.0g/L. The conversion rate of cinnamic acid was 89.2%; the yield of acetophenone was 83.4%.