Brosimum Alicastrum as a Novel Starch Source for Bioethanol Production

Abstract

Ramon (Brosimum alicastrum) is a forest tree native to the Mesoamerican region and the Caribbean. The flour obtained from Ramon seeds is 75% carbohydrate, of which 63% is starch, indicating its potential as a novel raw material for bioethanol production. The objective of this study was to produce ethanol from Ramon flour using a 90 °C thermic treatment for 30 min and a native yeast strain (Candida tropicalis) for the fermentation process. In addition, the structure of the flour and the effects of pretreatment were observed via scanning electron microscopy. The native yeast strain was superior to the commercial strain, fermenting 98.8% of the reducing sugar (RS) at 48 h and generating 31% more ethanol than commercial yeast. One ton of flour yielded 213 L of ethanol. These results suggest that Ramon flour is an excellent candidate for ethanol production. This is the first report on bioethanol production using the starch from Ramon seed flour and a native yeast strain isolated from this feedstock. This alternative material for bioethanol production minimizes the competition between food and energy production, a priority for Mexico that has led to significant changes in public policies to enhance the development of renewable energies.

Keywords

• bioethanol production
• starch
• Brosimum alicastrum
• Candida tropicalis