~ 38 ~ The Pharma Innovation Journal 2015; 3(11): 38-42 ISSN: 2277- 7695 TPI 2015; 3(11): 38-42 © 2015 TPI www.thepharmajournal.com Received: 05-11-2014 Accepted: 15-12-2014 Jatindra Nath Mohanty Centre of Biotechnology, Siksha O A nusandhan University Bhubaneswar, Odisha – 751003, India. Pratyush Kumar Das Centre of Biotechnology, Siksha O A nusandhan University Bhubaneswar, Odisha – 751003, India. Sonali Nanda Centre of Biotechnology, Siksha O A nusandhan University Bhubaneswar, Odisha – 751003, India. Priyanka Nayak Centre of Biotechnology, Siksha O A nusandhan University Bhubaneswar, Odisha – 751003, India. Puspita Pradhan Centre of Biotechnology, Siksha O A nusandhan University Bhubaneswar, Odisha – 751003, India. Correspondence: Pratyush Kumar Das Centre of Biotechnology, Siksha O Anusandhan University Bhubaneswar, Odisha – 751003, India. Comparative analysis of crude and pure lactic acid produced by Lactobacillus fermentum and its inhibitory effects on spoilage bacteria. Jatindra Nath Mohanty, Pratyush Kumar Das, Sonali Nanda, Priyanka Nayak and Puspita Pradhan Abstract Lactic Acid is one of the most industrially important acids which have a wide spread application. It is mostly present in two forms i.e. L-form and D-form. In this work the aim was to produce lactic acid from Lactobacillus fermentum via three different production medium viz. MRS Broth, Whey Basal Broth and Skimmed Milk Broth and optimization of these mediums to maximize the production, followed by purification of the crude lactic acid by Ion exchange chromatography. Titrimetric assay was carried out at each & every step to determine the level of purity along with the checking of anti-bacterial activity. High purity as much as 85 percent was achieved. Finally the purified elutes were subjected to Thin layer Chromatography (TLC) and their Rf Values were determined. Keywords: Lactobacillus fermentum, Lactic acid, Ion exchange chromatography, Antimicrobial activity, MRS Medium, Whey Basal Medium, Skimmed Milk Medium. 1. Introduction Lactic acid, also called α-hydroxypropanoic acid or 2-hydroxypropanoic acid, has a wide range of application in different fields and in general in preservation of human food stuffs [1] . Discovered by Scheele in 1780 and was considered as a milk component and in 1789 was named as “acide lactique” by Lavoisier. Later in 1857, Louis Pasteur discovered that it was a fermentation metabolite released by certain microorganism rather than being a milk component [2] . When glycogen is broken down in muscle, lactic acid occurs in the blood in the form of salt called – “Lactates” and can be again be converted back to glycogen in the liver [3] . Lactic acid has two optical isomers: L(+)-lactic acid and D(-)-lactic acid (see figure -1 below). US FDA (Food and Drug Administration) has classified lactic acid as GRAS (Generally Recognized as Safe) for use as a food additive. But at times D(-)-lactic acid is harmful to humans and results in acidosis and decalcification of bones [4] . Although the racemic DL-lactic acid is produced by chemical synthesis from petrochemical resources, but still, optically pure L (+) and D (-) lactic acid can be obtained from microbial fermentation and can be polymerized to high crystalline Poly Lactic Acid (PLA) [5, 6] . Thus, the production of lactic acid by microbial fermentation provides a better alternative to the environmental pollution caused by the petrochemical industries during the production of the racemic one. Fig 1: Stereoisomers of Lactic Acid