INTERNATIONAL JOURNAL OF AGRICULTURAL TECHNOLOGY

Volume 16, No. 06, Month NOVEMBER, Year 2020, Pages 1373 - 1384

Effect of prewashing silages of panicum virgatum l. on carbohydrate composition, enzyme hydrolysis and yeast fermentation

Florendo, P. DC. and Sharma-Shivappa, R. R.

Abstract Download PDF

Ensilages of Panicum virgatum L. prewashed with hot water and limewater solution were evaluated for carbohydrates composition, efficiency of enzymes hydrolysis and products of yeast fermentation. Samples of three switchgrass varieties prewashed with and without limewater solution, rinsed with hot water, analysed for reducing sugar, glucans, xylan, arabinan and acid soluble lignin,, subjected to 1:4 ratio of Cellulase Cellobiase enzyme hydrolysis and fermentation by common yeast. Composition analysis revealed Bomaster variety contains reducing sugars and glucan significantly higher than varieties of Performer and Colony but it was equally comparable in xylan, arabinan and lignin contents. Enzyme hydrolysis converted xylan into solubles in silages prewashed with limewater solution with 62.21% efficiency compared to 48.47% in hot water washed silages. Fermentate of switchgrass produced low amount of ethanol which was attributed to lack of sufficient glucan, while the high yiled of acetate was attributed to high contents of xylan and arabinan. Prewashing silages with limewater washout and neutrilize silages, enhances enzyme hydrolysis pretreatment and impact yeast fermentation. Recommendation is to select yeast with ethanol fermentation from both glucan and xylan and arabinan, improvement in the conditions of fermentation of pentose sugars in the absence of sufficient glucan. Information generated in this study is useful in the process of prewashing as complement of ensiling as preservation of feedstock intended for ethanol production.

Keywords

Panicum virgatum L., Variety, Cellulose, Hydrolysis, Carbohydrates, Fermentation

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