Table of Contents
Biotechnology Research International
Volume 2017, Article ID 1925820, 10 pages
https://doi.org/10.1155/2017/1925820
Research Article

Selection and Characterization of Potential Baker’s Yeast from Indigenous Resources of Nepal

1Department of Biotechnology, Kathmandu University, Dhulikhel, Nepal
2Biotechnological Research and Development Center Pvt., Ltd., Bharatpur, Nepal

Correspondence should be addressed to Tika B. Karki; pn.ude.uk@akitk

Received 12 July 2017; Accepted 20 November 2017; Published 13 December 2017

Academic Editor: Yau Hung Chen

Copyright © 2017 Tika B. Karki et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

The study aims to isolate the yeast strains that could be used effectively as baker’s yeast and compare them with the commercial baker’s yeast available in the market of Nepal. A total of 10 samples including locally available sources like fruits, Murcha, and a local tree “Dar” were collected from different localities of Bhaktapur, Kavre, and Syangja districts of Nepal, respectively. Following enrichment and fermentation of the samples, 26 yeast strains were isolated using selective medium Wallerstein Laboratory Nutrient Agar. From the differential tests which included morphological and microscopic observation and physiological and biochemical characterization such as nitrate reduction and lactose utilization tests, 8 strains were selected as possible Saccharomyces strain. The selected strains were further assessed for their efficient leavening ability by tests such as ethanol tolerance, osmotolerance, invertase test, and stress exclusion test. The three most potent strains ENG, MUR3B, and SUG1 isolated from grape, Murcha, and sugarcane, respectively, were used in the fermentation and baking of dough. These strains also carried a possibility of being used as industrial baker’s yeast.