Fibernodes in flax and other bast fibers

Abstract

Fibernodes in flax, hemp and stinging nettle fibers were studied using light microscopy(1). The fibers were prepared both mechanically and chemically. The observations showed that flax, hemp and stinging nettle fibers carry numerous unevenly distributed disturbances that we name fibernodes, visible as single or double lines in ca 60-90degrees angle from the fiber direction. Fibernodes were not present on the seed hair fibers of cotton and kapok. This structure represents a weak point in pulling, at least for flax fiber. The fibernodes in flax were highly affected by cellulases, while these enzymes did not visually affect cotton fibers. Pectinases and xylanases had no detectable effect on fibernodes. The fibernodes in hemp seemed to be more resistant to cellulase than in flax. The high sensitivity of fibernodes in flax indicates that cellulase should be avoided in any enzymatic retting process of flax, since this will be harmful for the strength of the fibers.