保护剂对费氏弧菌冻干粉复苏及毒性检测的影响

Influence of cryoprotectants on resuscitation and toxicity test of Vibrio fischeri freeze-dried powder

通过正交试验探究不同浓度脱脂乳、甘油和海藻糖组成的复合保护剂对费氏弧菌的保护作用,确定最佳保护剂配比,并进一步研究保护剂对冻干粉发光复苏特性和毒性检测准确性的影响。结果表明,15%脱脂乳、5%甘油和12.5%海藻糖组成的复合保护剂保护效果最好。添加保护剂后,干粉发光复苏稳定时间从传统的15 min缩短至5～10 min,并能准确检测4种金属的毒性大小。在最佳冷冻保护剂的保护下,费氏弧菌冻干粉在缩短了复苏时间的同时对金属的毒性检测没有影响,有利于费氏弧菌在环境监测中使用。

In order to improve the resuscitation quality of photobacterium freeze-dried powder, the orthogonal experiment was used in the study for optimizing freeze-drying cryoprotectants. In the experiment, Vibrio fischer/ was chosen to be the object of study and skimmed milk, glycerol, trehalose were mixed in different ratio as different freeze-drying cryoprotectants （ Vibrio fcheri freeze-dried powder with no cryoprotectants set as the blank experiment）. The resuscitation rate of each kind of Vibrio fischeri freeze-dried powder which were under the protection of different freeze-drying cryoprotecrants and the luminescence characteristic was measured. At the end, with the aim of knowing if the addition of the cryoprotectants might have some imquence on the accuracy when the freeze-dried powder was used in environmental monitoring, the toxicity of four metals was test. According to the resuscitation rates of each kind of freeze-dried powder we got that different cryoprotectants had different protective results, the freeze-drying cryoprotectants which was made up of 15 % skimmed milk, 5 % glycerol, 12.5 % trehalose gotthe highest resuscitation rate 99%, and the blank experiment just got the lowest rate 1% , so it was concluded that the former was the the optimize freezedrying cryprotectants of Vibrio fischeri, and the freeze-drying cryoprotectants has great influence on the resuscitation of Vibr/o fischeri freeze-dried powder. After analyzing the luminescence characteristic of the freeze-dried powder with the optimized cryoprotectants, it turned out that the resuscitated time was reduced from 15 min in the standard method to 5 - 10 min, and the luminescence was steady. Especially the kind of freeze-dried powder with initial relative luminescence unit（RLU） between 100- 200, the resuscitation time of which just 5 min and had higher stability. The toxicity test of four metals had the same result of the standard method, so we can predicate the cryoprolectants had little influence on the useness of freezedried powder in mental test. In all, under the protection of the optimized freeze-drying cryoprotectants, the Vibrio fischeri freeze-dried powder made it possible to improve the efficiency of environmental monitoring without any influence on toxitoy test.