Vol. 8, Issue 10 (2019)

Author(s):
Pooja Thapak, Dr. Ravi Upadhyay and Dr. Neelam Tripathi

Abstract:
Citric acid is the most versatile and widely used organic acid in the field of food and pharmaceutical industries which is non-toxic GRAS compound with pleasant sour taste. Its a natural constituent and common primary metabolite of plants and animals formed during tricarboxylic acid cycle or Krebs cycle. The production of citric acid have been evaluated upon variety of bacteria, fungi & yeast. The conventional methods have proved to be complex, expensive, and not eco-friendly but microbial production is supposed to be feasible & cost effective. Thus, in present investigation citric acid production by Aspergillus niger and Saccharomyces cerevisiae is comparatively estimated by using kitchen waste as a source of nutrition. Indigenously isolated A. niger and S. cerevisiae were inoculated in the homogenized and partially sterilized organic mixture prepare from kitchen waste. The standard peak generated in HPLC chromatogram for pure citric acid marker showed ad retention time of 9.732±0.3min. When compared to the standard, the percentages estimation of citric acid produced due to fermentation activity of A. niger on kitchen waste was observed to be 0.569%, while the activity of S. cerevisiae results into the yield of 0.325% citric acid in sample extract within 15 days at ambient temperature. Citric acid production by A. nigerby using homogenized mixture of kitchen waste observed to be higher compared to the yield due to activity of S. cerevicea on same substrate. The improvement in yield of organic acid production using such substrate could be further worked out by modifying the nutritional quality of organic substrate by addition of mineral supplements which is matter of further investigation.