METHODS FOR PRESERVATION OF ALKANE-UTILIZING RHODOCOCCUS SPP EXPEDIENT FOR CULTURE COLLECTION PRACTICE

The following conditions were found to be optimal for the preservation of pure cultures of alkane-utilizing rhodococci: storage on deficient agar, in distilled water, in a 0.5% NaCl solution, and in a lyophiliz ed state at 4 degrees C in sealed ampules. The highest survival rate w as achieved through lyophilization of suspensions with an initial tite r of 10(8) - 10(9) cells/ml in the presence of sucrose-gelatin agar an d rehydration by a 0.5% NaCl solution. Long-term preservation in lyoph ilized state was most efficiently endured by representatives of Rhodoc occus ruber. Alkane-utilizing organisms were shown to be tolerant to a dverse conditions of lyophilization and prolonged storage. After 3-yea r-long storage in a lyophilized state, the respiration activity of hyd rocarbon-utilizing rhodococci was about 3.8 mu l O-2/h/mg dry biomass. We believe that the increased content of unsaturated fatty acids in R . ruber cells grown on propane contributed to their survival rate, whi ch was as high as 31.6% and remained constant during a long period of storage.