Sugar-Rich Hydrolysates of Palm Oil Empty Fruit Bunch Production Through Two Step Solid State Fermentations and Its Conversion to Ethanol

Abstract

An improvement hydrolysis to produce a sugar-rich palm oil empty fruit bunches (POEFB) through a two-step solid state fermentation using Aspergillus niger and Tricodhermaviride has been investigated. Initial solid state fermentation was done in a hundred grams of water saturated POEFB medium in the 5L flaskwithout the addition of any nutrient. The medium was sterilized, inoculated with A. niger, and incubated at 30 C for 5 days. The sugar-rich hydrolysates in POEFB medium were harvested through filtration by adding 100 ml distilled water. Then POEFB sugar-rich free hydrolysates were subsequent re-sterilized, inoculated with T. viride and at the same temperature. After for 4 days incubation,sugar-rich hydrolysates also extracted and pooled. The analysis proves that the sugar-rich hydrolysates containing 6.52% (33.4 g sugar in a total volume of 512 ml or 65.2 mg/ml) as a reducing sugar. Further analysis by Gas Chromatograph (GC)astransmethylated sugar as alditol acetates revealed that 63% of POEFB hydrolysates are monosaccharides (41.1 mg/ml). Anaerobic fermentation of sugarrich hydrolysates using Saccharomyces cerreviseae at 30 C for 36 hours gave yield maximum 19.1 mg/ml ethanol concentration with efficiency 46.5%, respectively.