Abstract

Himalayas are the natural reservoir of complex and diversified gene pool. Three Shiwalik Himalayan intracellular phytase producing budding yeasts were assayed for in vitro degradation of natural animal feed substrates. Phosphorus availability was found to enhance upto 70% yeast cultures during in vitro biodegradation of natural animal feed substrates. A direct correlation between intracellular phosphate concentration and phytase activity suggested the use of  whole cell preparations in place of purified enzymes. Zymogram analysis revealed the presence of single high molecular weight isoform of the enzyme phytase. Based on 5.8S-ITS-rDNA sequencing, using ITS1 and ITS4 primers, the cultures were identified as Candida tropicalis (B4), Issatchenkia orientalis (PA4) and Pichia gluermondii (SS1). Indigenous I. orientalis strain PA4 was found superior  among all the yeasts strains and therefore can be developed as successful inoculant for animal nutrition as well as environmental management under Himalayan ecosystems.  

Key words: Phytase, Shiwalik Himalaya, phytase biodegradation, 5.8S-ITS rDNA, Yeast identification.