Role of magnesium ions on Improvement of Fermentative activity of local yeast isolates Saccharomyces cerevisiae for ethanol production

The interest in bio-ethanol increase as biofuel, it seems to be a good alternative for fossil fuels. The growth of yeast Saccharomyces cerevisiae is influence in micronutrient like ions. This research aims to evaluate the influence different amount of magnesium as co-enzyme in growth and fermentation of yeast S. cerevisiae which isolated from different local sources. The batch fermentation process was followed at different magnesium concentrations as magnesium chloride at incubation temperature 30C○ and pH 4.5, best supplement concentration was 1.25 gm/l by measuring the mass of the released carbon dioxide. Supplement media with magnesium prolonged exponential growth, reduced the decline in fermentation activity resulting in reduced the time required for the conversion glucose into ethanol.