| The paper researched the following contents: purification and identification of ricinine in castor bean meal, separation and identification of relative bacteria, primary degradation mechanism, and optimization of conditions for degradation of ricinine by biological method.Ethanol concentration, and ratio of materials to extracting liquid were significant (p<0.05) to the extracting technology. A simple and direct method for ricinine qualitative analysis was established by using TLC. It was found that macroporous adsorption resin 4# was the best for separating ricinine, and the purified product contained 98.55% (W/W) ricinine. Comparing with conventional extracting method, yield of ricinine significantly increased, and extracting duration greatly reduced.The strains of T1 and B31 were isolated and enriched from castor-planting soil, and screened with ricinine as the sole carbon and nitrogen source. These two strains were observed by modality and their characteristics of physiology and biochemistry was determined, then the mechanism and the rate of degradation had been studied. The results showed that the strains of T1 and B31 belong to Pseudomonas, aerobe, and their growth temperature range from 35 to 37℃and pH 7.5 to 8.2, respectively. The degradation experiment showed that they both produced endocelluar enzymes, and the degradation products were found by the way of TLC and HPLC. Fe3+ had promoting effect on growth and enzyme-producing of the two strains. But cell extracts of T1 contained activities corresponding to nitrile hydratase and amidase, while B31 contained activities corresponding to nitrilase. They were different in degradation mechanism. Their degradation rates reached to 86% and 87% under the optimized conditions. The experimental results of fermentation indicated that these two strains exhibited good growth in castor bean meal, and their degradation rates reached to 84% and 85%, while the gross content of crude protein had not decreased.
|
PDF Full Text Request