Biosoftening of arecanut fiber for value added products

The arecanut husk fibers are predominantly composed of cellulose and varying proportions of hemicellulose, lignin, pectin and protopectin. Microbes that selectively remove lignin without loss of appreciable amounts of cellulose and fiber strength properties are extremely attractive for the biosoftening of arecanut fiber. The fungal growth occurs during the first 72 h of incubation and by one week, enzyme production reaches the maximum level, thereby improving color and softness of the fiber. Maximum MnP production of 233.2 IU ml(-1) was observed at pH 7.0 for Phanerochaete chrysosporium and a maximum activity of 221.8 IU ml(-1) was observed at pH 5.0 for Phanerochaete strain. Maximum improvement of color (brightness) and softness and maximum MnP production of 321.3 IU ml(-1) was achieved in a medium lacking both carbon and nitrogen for R chrysosporium whereas maximum improvement in color and softness and MnP production of 341.2 IU ml(-1) was achieved in a medium lacking only carbon for Phanerochaete sp. The fiber treated with P. chrysosporium showed 35.1% and Phanerochaete sp. showed 25.7% increase in strength when compared to the untreated fiber. Elongation of the fiber treated with R chrysosporium was 5.0% and that treated with Phanerochaete sp. was 4.2% compared to the control fiber which had an elongation of 3.7%. The biosoftened arecanut fibers can be exploited commercially for the production of furnishing fabrics, textiles etc by blending with cotton, viscose and polyester. (c) 2005 Elsevier B.V. All rights reserved.