Isolation of Microorganisms from Fermenting Parkia biglobosa in Kuje Market, Abuja

Abstract

Lactic acid bacteria constitute one of the most abundant groups of microorganisms in most fermented food products across Nigeria. The biochemical signatures of these species make the ideal catalysts for a range of processing events with the food industry. This study was undertaken to isolate and screen for lactic acid bacteria strains obtainable from fermented Parkia biglobosa seeds purchased at a rural seed market in Abuja. Data obtained revealed that seven morphologically distinct bacteria isolates were obtained using antifungal induced (0.3 mg/ml Fluconazole) yeast extract, malt extract, peptone, glucose, agar media. The seven bacterial isolates were given the designations TEA, TEB, TEC, TED, TEF, TEJ, and TEL respectively. The obtained all but two isolates (TEB and TEL) were all capable of fermenting fructose, glucose, lactose, sucrose and trehalose as the sole carbon source in the broth. Morphological examination revealed that the isolates obtained were non-spore forming gram positive colonies ranging from creamy to white, clear, cocci and rod-shaped, smooth textured and flat elevation with transparent opacity. Their Growth measurements were determined by measuring the optical density of the cells in broth using spectrophotometer at 600nm over a 96 hour incubatory period in nutrient broth at 37oC. Isolate TEC displayed the highest overall growth pattern over the 24 hour period via optical density readout 1.85, 2.40, 2.65, 2.80. All isolates except TEB were negative for catalase and citrate, thereby suggesting that TEB was a specie of the Citrobacter family. All isolates tested negative for coagulase, indole and motility tests. Suggestions from the data obtained lean towards the use and suitability of the isolated bacteria as ideal cultures for commercial fermentation.