Fermented Corn Waste Liquor as a Potential Source for Probiotic Lactic Acid Bacteria

Abstract

Probiotic bacteria offer potential beneficial uses to man. The most common types are the Lactic Acid Bacteria (LAB) which is sourced mostly from fermented diary and vegetable products such as yoghurt, cheese and sauerkraut. Although some fermented cereals are known to contain LAB, limited information is available on the massive production of LAB from low cost fermented meals such as corn mash waste. Hence the efficiency of 72h- corn waste liquor as a rich source for probiotic LAB was evaluated. The liquor aseptically recovered from sieved, wet-milled 72h-fermented corn mash wastes was cultured into DeMan Rogosa Sharpe (MRS) medium, Yeast extract agar, MacConkey agar, Nutrient agar and Sabouraud dextrose agar, to obtain their mean microbial counts. The most common LAB colonies from MRS plates were identified as Lactococcus lactis, Pediococcus acidilactici and Lactobacillus plantarum by morphological and physiological tests. Equal concentrations of the LAB isolates at their determined peak growth periods (14h, 18h &22h), were screened for antibacterial potentials against 1x103mgml-1 concentration of the test pathogenic organisms using cross-streak method. Results obtained revealed a much higher LAB counts (>2.40x107cfuml-1) than that of other organisms that ranged from 2.4x101 to 2.1x103cfuml-1. Coliforms were scantily recovered (<3cfuml-1). The degree of susceptibility of the pathogens to the test LAB varies. However, the order of antibacterial potentials determined by the zone of inhibition was Lactobacillus plantarum> Lactococcus lactis > Pediococcus acidilacti which had slight antibacterial effect (<0.58mm) on the test pathogens. This gave an indication that corn waste liquor is a potential source of probiotics that can be utilized for the prevention of diseases that are caused by the susceptible pathogens.

Key Words: Probiotics, Lactic acid bacteria, Fermentation, Corn waste-liquor.