(482e) Flash Hydrolysis for Producing Algal Hydrolysate and Its Application in Enzymatic Saccharification of Lignocellulosic Biomass

Flash hydrolysis using subcritical water is a novel and versatile process for selectively hydrolyzing polymeric components of algae biomass. In this study, our objective is to use high water content of algal biomass advantageously for extracting proteins and carbohydrates in a short residence time (few seconds). The present study was focused on the extraction of proteins from Scenedesmus spp. using subcritical water in a continuous flow reactor. The effect of temperature and residence time on the yield of peptides and free amino acids in liquid hydrolyzate are studied. About 60-80 wt% of proteins in microalgae could be extracted within few seconds in the temperature range of 200-325˚C under subcritical water conditions. The algal samples were first characterized for biochemical compositions and then optimal conditions for protein extraction using subcritical water were determined.

Algal hydrolysate obtained via flash hydrolysis at different temperatures was investigated for its use as reaction medium during saccharification of lignocellulosic biomass. The objective was to replace conventionally used buffer solutions and optimize the enzymatic hydrolysis of biomass in the presence of nutrient rich algal hydrolyzate. It is understood that algal hydrolyzate is an additional protein source to the reaction medium that are irreversibly absorbed by lignin present in lignocellulosic biomass. This helps in increasing the hydrolysis rate by reducing the interference in cellulase activity.