Ethanol fermentation for main sugar components of brown-algae using various yeasts

The conversion of marine biomass to renewable energy was widely considered an alternative to fossil fuel, especially with regards to bio-ethanol blending in gasoline. Due to the absence of carbohydrate content, brown algae was expected to be possible organism for achieving ethanol production, but the selected microorganism needs to effectively ferment. We carried out experiments with 8 types of yeast affiliated with each different family for ethanol production and tested the effects of different carbon sources. Low concentrations of substrate were found to mostly increase the cell growth from all different substrates, but a significant increase in ethanol production was detected on the mannitol substrate. Saccharomyces cerevisiae (KCCM50550) was found to produce the highest result among all yeast strains, and ethanol production reached 2.59 g/L from 10.0 g/L of mannitol. A higher content of ethanol production in the fermentation was evident when the carbon source concentration increased.