Adaptation of some yeasts to pentose rich vineplant wood rods hydrolysate and ethanol production

Due to the increasing World population and changing consuming habits, the need for energy is rising sharply. However, repository sources of energy are limited and the demand for the renewable sources are continually increasing. All the plant or animal based matters which contains carbohydrates as their main components are termed as Biomass Energy Source. And this energy, is a kind of sustainable energy that is obtained from the agricultural –organic wastes. At the first part of this study according to their positiveness for pentose utilization, 13 strains were submitted to fermantation on defined media as pre process. At this stage, by the five strains that have higher than others in terms of activity, fermentation on hydrolysate medium that was prepared by the hydrolysation of the bunches with weak acid pretreatment were carried. Their productiveness and yields were compared on both fermantation conditions. The strain belong to P. kudriavzevii species was determined as superior than others. By using this strain, sequential fermentation studies for the adaptation were carried on hydrolysate medium. During the all fermentation processes, growth of the strains were monitored by counting the cells and measuring the reducing sugar and alcohol concentrations, daily. As the results of the fermentation by P. kudriavzevii on defined media and on hydrolysate media were compared; 63% increase in ethanol concentration (g/L) and 1.6 fold (g/g) increase in ethanol productiveness were obtained. As conclusion, the hydrolysate medium which was prepared totally from organic based waste could be used for the production of energy as an alternative/sustainable by the adapted yeasts due to fermantation is shown.