Comparative study of killer and sensitive yeast strains and to isolate killer toxins

Maninder Kaur Dhaliwal; Varsha Patnaik; Lata Patnaik

Volume : IX, Issue : VI, June - 2019

Comparative study of killer and sensitive yeast strains and to isolate killer toxins

Maninder Kaur Dhaliwal, Varsha Patnaik, Lata Patnaik

Abstract :

Various yeasts were isolated from samples such as rotten, fermented food & fruit juices. Among 19 yeast strains isolated only 4 had killer activity. Isolated yeast was examined for killer activity by using standard sensitive strain of Candida stellata NCIM 3433 procured from NCIM Pune. The isolate which presented to have highest killer activity was identified as Candida lipolytica by VITEK method. The antibacterial activity was highest for Escherichia coli and Pseudomonas aeruginosa with reduced activity for Staphylococcus aureus and Klebsiella pneumoniae. The effect of pH, temperature and additives on toxin production was studied. The crude toxin was estimated by Lowry’s method & SDS –PAGE study was also carried out. Killer toxin was further purified using ammonium sulfate precipitation & characterized for few properties