PECTINOLYTIC ENZYMES FROM ACTINOMYCETES FOR THE DEGUMMING OF RAMIE BAST FIBERS

Actinomycetes isolated from 10 different soil and compost samples were screened for production of pectinolytic enzyme activities when grown on pectin-containing solid and liquid media. Pectinolytic enzymes, det ected by using plate diffusion tests with a medium containing ramie (B oehmeria nivea) plant material as the sole carbon source, were mainly pectate lyases, but low activities of pectinesterases were also observ ed. Polygalacturonases and polymethylgalacturonases were not produced. Multiple forms of pectate lyases were detected in the culture superna tants of some of the strains by using the zymogram technique of isoele ctric focusing gels. Xylanolytic and cellulolytic activities were alwa ys found to be associated with pectinolytic activities. None of the pe ctinolytic enzymes were produced in a medium with glucose as the sole carbon source. Treatment of ramie bast fibers with crude enzyme prepar ations from a selection of strains showed a good correlation between t he pectate lyase activity applied and the degumming effect, resulting in good separation of the bast fibers.