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Information × Registration Number 0201U004502, 0198U009006 , R & D reports Title The development of effective means of obtaining new forms of vitamins, protein-vitamin preparations on the base of current biotechnological methods and studying of physiological and biochеmical ground their utilization. popup.stage_title Head Stenchuk Mykola Mykolajovych, Registration Date 11-06-2001 Organization Institute of Animal Biology Ukrainian Academy of Agrarian Science popup.description2 The effectiveness of nitrosoguanidine (NTG) in generating flavinogenic mutants of the yeast Candida famata was studied. It is found that the mutagenic effect of NTG on C.famata yeast is more intensive at pH 6.0 than at pH 8.0. Over 1 % of the surviving cell population were mutants with elevated flavinogenic activity or auxotrophic strains after 30 min -long treatment of yeast with 0,02 % solutions of NTG at pH 6.0.We applied an four-step selection procedure using NTG to achieve a 300-fold increase in riboflavin production ( 75-100 mg/l ) as compared to the parent strain. One of them can synthesize up to 200 mg/l of riboflavin in the medium containing wheat wort and distillery refuse (1:9 ). In this study, we evaluated also the effectiveness of NTG in generating auxotrophic and pigmented mutants of the Phaffia rhodozyma yeast. It is found that 0,5% of the surviving cell population were mutants with elevated concentrations of carotenoids and auxotrofic strains. NTG mutagenesis generated some strains th a t contained 300% more carotenoids that the parents ( e.g., 330 g/g compared with 88 g/g in the parent strain). A study was made of biological efficiency of their biomass in the rations of broiler chicks. The increase of glutationperoxidase activity in blood plasma of chicks has been established. The improvement strains can be used for futher development of knowledgе about mechanisms of overproduction of vitamine B2 and carotenoids and their biological efficiency in the rations of animals. Product Description popup.authors popup.nrat_date 2020-04-02 Close