Degradation of rice straw by Pleurotus flabellatus.

Rajarathnam, S. and Wankhede, D. B. and Zakia, Bano. (1987) Degradation of rice straw by Pleurotus flabellatus. Journal of Chemical Technology and Biotechnology, 37. pp. 203-214.

PDF J. Chem. Tech. Biotechnol. 1987,31, 203-214.pdf - Published Version Restricted to Registered users only Download (743kB)

Abstract

Degradative changes in the constituents of rice straw substrate during the growth and commercialproduction of fruit bodies by Pleurotus flabellatus were investigated. There was a continuous increase in the free sugars from the time of inoculation until the end of harvesting of the fruit bodies, whereas the free amino acids reached a maximum at the end of mycelial growth and showed a slight decrease after fructification. Glucose, xylose, arabinose, cellobiose and a higher oligosaccharide represented the spectrum of sugars produced. Of the 12 amino acids (apart from two peptides) identified, aspartic acid, histidine and tyrosine were the major components, Solubilities and spectral characteristics of lignin degraded in the straw substrate were studied using alkali-extracted lignin. Laccase and protease activities in the straw substrate at different stages of fungal ‘degradation could be correlated to the decreases in the staw lignin and protein contents, respectively. Colour reactions of the fungus on several phenolic media, demonstration of phenolic oxidases in the straw substrate, and ability of the fungus to degrade lignin conclusively proved that the fungus under study is a typical ‘white rot’ fungus. Degradation of the straw substrate by the fungus reached a maximum at the end of harvest of the fruit bodies. The spent straw substrate (left over after harvesting the fruit bodies) contained free sugars and amino acids, respectively 5 and 2 times the concentration of those in the undegraded straw substrate, and lignin decreased to about 25% of the level in the straw before fermentation. Potential applications of the spent straw substrate as an upgraded form of rumen feed and for the production of single-cell protein are discussed.

Item Type:	Article
Uncontrolled Keywords:	Pleurotus flabellatus, rice straw, single-cell protein, lignin degradation, phenolic oxidases, spent straw utilisation.
Subjects:	500 Natural Sciences and Mathematics > 07 Life Sciences > 04 Microbiology > 04 Fungi 600 Technology > 05 Chemical engineering > 04 Fermentation Technology
Divisions:	Fruit and Vegetable Technology
Depositing User:	Food Sci. & Technol. Information Services
Date Deposited:	26 May 2016 06:50
Last Modified:	11 Jun 2019 10:35
URI:	http://ir.cftri.res.in/id/eprint/3683

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