Preparation And Mechanism Of Controlled-release Granular Formulation Of Zhongshengmycin

Zhongshengmycin was a new kind of agricultural antibiotic.lt was produced by Streptomyces lavendulae var. Hainanenisis. The formulations now in market were water formulation and dust powder. Because much of the Zhongshengmycin had to be put in to soil in order to control the pathogen. Furthermore, the experiments have showed that the duration time of the standard formulations was seven days, while the period of on disease to plants was more than seven days. According to the characteristics of Zhongshengmycin, we have tried to make it to be a new formulation-controlled release granular (CR)formulation. This would enable smaller quantities of antibiotic to be used over a longer duration, with lower run-off. Now we have prepared CR granual formulation of Zhongshengmycin through various methods. The results as follows:1. Sodium carboxymethyl cellulose (NaCMC) was a major fator that affected the release rate of CR formulaton of Zhongshengmycin. And the concentration of CMC was more, the release rate was slower.2. According to the several important factors that affected the release rate of CR formulaton of Zhongshengmycin. The final combination and percentage of each ingredient was 10% of CMC, 50% of Zhongshengmycin(DP), 40% of Peat moss, diameter of granules was 6mm, Mol concentration of aluminum ion was 0.6M.3. Experiments carried out in water showed that the release of Zhongshengmycin from CR formulations in water was three times more than dust formulation.4. Experiments carried out in soil have showed that the effect of Zhongshengmycin CR formulations was very obvious in soil. Zhongshengmycin couldn't be detected after nine days through bioassay methods in dust formulations, while Zhongshengmycin still could be detected after twenty-five days in CR formulaton.5. Release kinetics in water and in soil was studied. Whatever in water or in soil, the release kinetics of Zhongshengmycin from the CR formulation was evaluated, fitting the data to the generalised model.y = k1e-k2ty was the quantity of Zhongshengmycin released at time t; ki and kz were constants.6. When adjuvant was put into CR formulation of Zhongshengmycin , an even longer time release of Zhongshengmycin was successfully achieved. Among the adjuvants that were choosen, C8-10 was the best, TX-10 and QUICK T took the second place.7. The stability of CR formulation of Zhongshengmycin was also tested, the titre of CR formulation of Zhongshengmycin was almost equal to dust formulation,the discrepancy wasless than 6%, when put CR formulation at normal temperature about half a year and at 50centigrade about one month.8. The technics flow of Zhongshengmycin granular controlled-release formulation wasmade.In conclusion, it was possible to construct Zhongshngmycin containing CMC granules that prolongd the availability of the antibiotic through controlled release. These results hold out the hope that waste caused by excessive application of the commercial formulations of Zhongshengmycin may be significantly decreased.