Effect of harvesting age of plant and pectinolytic selected-fungi in biodegumming ramie performance

Ramie is one of the long natural fiber has strong mechanical properties. To improve the quality of ramie fiber, this study developed a bio degumming method from superior isolates of pectinolytic fungi Rhizopus sp. and optimization of raw fiber based on harvesting time. The results of the pectinolytic fungi selection were used as a bio degumming bio starter under optimum conditions of pH and temperature. Also, fiber material harvested at 50-day and 60- day to obtain an increase in the physical quality. The bio degummed fiber was analysed to determine the tenacity and fineness, the functional groups contained, thermal analysis, moisture regain and content, material polymers, and degree of crystallinity. Based on the results, the finest ramie properties with 50-day harvested fiber are as follows: strength 24.54 ± 0, 02 g/tex, elongation 12.04 ± 2,90%, fineness 1.33 ± 0,17 tex, moisture regain 8.23 ± 0,18 %, and moisture content 8.96 ± 0,21 %. Ramie fibers at initial conditions and after bio degumming at 50 and 60-day harvested had the same pattern of thermal stability. The dyeability test showed that the degummed 60-day harvested fibers has the greatest dye fixing ability. The bio degumming process with this method can improve the quality and dyeability of the rami fiber which can be used for future applications.