P30: Carbohydrate composition and potential fermentation inhibitors in hydrolysates from Agave atrovirens bagasse

Thermochemical and enzymatic treatments of lignocellulosic materials, result in fermentable hydrolysates, with sugar yields depending on both the source of plant material, and the method of hydrolysis employed. Fermentation efficiency relies on the type of sugar produced (hexoses or pentoses), as well as in the type and relative concentration of fermentation inhibitors.

One of the most interesting sources for lignocellulosic biomass is Agave atrovirens, the largest of agave plants, exclusive to the highlands of central and northern Mexico, a species which can grow successfully in marginal lands and with very low water requirements.

Thermo-chemical treatments were made to biomass materials from Agave atrovirens. Chromatographic analysis revealed strong differences in the content of syringaldehyde, furfural, 5-HMF, acetic, formic and levulinic acid, from different hydrolysis conditions. Glucose and xylose were the most abundant monosaccharides present in the hydrolysates. After adjusting the fermentable sugar concentration, and the nutrient content, the alcoholic fermentation parameters were registered for 2 commercial yeast cultures.

Agave lignocelluloses provided high sugar yield, low concentration of inhibitors, and high fermentability by the yeast strains tested.