Extraction and Characterization of Bacteriocin from Cucumber (Cucumis Sativum) Extract

Lactic acid bacteria are a group of Gram positive non – sporulating rods or Cocci, which produce lactic acid as one of the main fermentation products of the metabolism of carbohydrate. Bacteriocins are ribosomally synthesized extra cellularly released low molecular mass peptide. The present study aimed to isolate lactic acid bacteria (LAB) extract bacteriocin from cucumber (Cucumis sativum) extract. LAB was identified using conventional biochemical test and by sugar fermentation using API50CHL as Lactobacillus plantarum and Lactobacillus acidophilus. Bacteriocin extracted from the isolated LAB was tested for antibacterial activity on S. cereus and E. coli highest activity zone of inhibition of 9.3+0.33mm on Staphylococcus aurues was obtained. Characterization of the bacteriocin extract shows that they are thermo stable (40oC – 121oC) active over a wide range of pH (3 – 11) inactivated by the enzyme trypsin and addition of sodium dodecylsulfate (SDS), Tween 80 and urea reduced the antibacterial activity, while addition of EDTA enhanced the antibacterial activity.