Studies of Bioethanol Production from Some Carbohydrate Sources by Gram Positive Bacteria

Abstract

Fermentation is a process by which large organic molecules are broken down in to simpler molecules as the result of the activity of microorganisms. Bioethanol is produced by the activity of some bacteria, and yeast, and their actions on substrates containing carbohydrates. Biofuels are a wide range of fuels that are in some way derived from biomass. Biofuels are gaining increased public and scientific attention, due to factors such as oil price spikes and the need for increased energy security.
It was observed that nutrients play a vital role in the process of fermentation. During the present study, seven bacteria were isolated from rotten fruits, out of which four bacteria (A, B, X and Y) all bacteria were gram positive and rod-shaped. They were able to ferment carbohydrate and produce bioethanol. The different substrates barley, oat, maize and sugar beet were used for bioethanol production. During the present investigation, the effects of different macro- and micro-nutrients on bioethanol production were also assessed.
It was observed that after supplementation of 5 ml and 10 ml of macronutrients (carbon, nitrogen, sulfur and phosphorus) in all four substrate solutions (barley, oat, maize and sugar beet), the barley had produced the most bioethanol. Thus, it was observed that macronutrients had a relevant effect on bioethanol production. On the contrary, large amounts of production were not seen when micronutrients (aluminum, copper, chromium and zinc) were added in pure form.