Production of enzyme mixture from Penicillium funiculosum for converting cottonseed hulls to lignin and sugars

Numerous types of enzymes are produced by Penicillium funiculosum under submerged fermentation. Many of these enzymes are utilized in both animal food preparation and biomass conversion industries to convert biopolymers to sugars and allow better access to starch and other nutrients that are bound. Our work was to optimize the submerged enzyme mixture production of the Penicillium sp. and to apply the plethora of enzyme types produced to cottonseed hull conversion in an effort to recover lignin, C5 and C6 sugars. We identified fermentation parameters of carbon and nitrogen substrates along with agitation speed and gassing volumes which led to the greatest yield of enzyme protein in the shortest amount of process time. Thirty-two enzyme activities were identified in the production ferment liquor. The total protein yield was 4.8% in the raw ferment prior to any downstream recovery concentration. When the enzyme mixture was applied in a conversion scheme for hydrolyzing cottonseed hulls to lignin and sugars; it was observed that lignin was recovered at a purity of greater than 98%.