冷风干燥制备高活菌的恶臭假单胞菌菌粉

Preparation of high viable count Pseudomonas putida bacteria powder by cold blast drying

摘要:

【目的】获得高活菌恶臭假单胞菌菌粉，提高菌体干燥及保藏存活率。【方法】选用冷风干燥法制备活菌粉，并优化吸附载体与保护剂。【结果】冷风干燥制备恶臭假单胞菌菌粉干燥存活率普遍达到65%以上，显著优于喷雾干燥(24%)；对载体与保护剂进行正交试验优化，确定了载体为混合的硅藻土和碱处理玉米芯粉，混合比为1:2，保护剂(质量比)为甘露醇7%、谷氨酸钠5%、甘油1%，制得菌粉活菌数为1.03×1011 CFU/g，室温保藏30 d和4 °C保藏60 d存活率分别达到40.54%和71.67%。【结论】冷风干燥温度相对较低(10?40 °C)，对菌体损伤小，碱处理玉米芯粉、甘露醇和谷氨酸钠是提高菌粉保藏存活率的重要因子，此法克服了革兰氏阴性菌菌粉不易制备和不耐保藏的瓶颈。

Abstract:

[Objective] This study aimed to prepare high viable count Pseudomonas putida bacteria powder, and improve the viability of drying and elongate the preservation period. [Methods] We selected cold blast drying technology to prepare bacteria powder, and optimized carriers and protective agents. [Results] Viability of drying was 65% on behalf of cold blast drying, which was significantly superior to spray drying (24%). Carriers and protective agents with orthogonal experiments were applied to obtain optimal formulation of preparation bacteria powder. The result was?as follows: as bacterial cell carriers, diatomite and corncob powder pretreated by Ammonia were mixed with ratio of 1:2. 7% mannitol, 5% sodium glutamate and 1% glycerin were mixed as protectives (W/W). Viable cell count was 1.03×1011 CFU/g in instant preparation. The viability was 71.67% and 40.54% after 60 d storage at 4 °C and 30 d storage at room temperature (RT) respectively. [Conclusion] Cold blast drying had little damage to bacteria because of its relatively low temperature (10?40 °C). Corncob powder pretreated by Ammonia, mannitol and glutamate had positive effect on preservation of bacteria powder. This method was successfully applied to resolve the difficulties of long-term preservation of gram negative non sporing bacteria.