Abstract:

In order to solves the problems biodegumming on low efficiency and instable quality, using Apocynum as the subject, Biorecalcitrance of Apocynum bast fibers was investigated from the aspects of composition and structure. The results show that the gum ration of gum substance in Apocynum bast is 45%~55%,  which the  higher than that to ramie, hemp, flax, jute, et al. The colloid laver is thicker and the fiber bundles are arranged in an orderly manner in Apocynum bast. The outer and inner layer in textura epidermoidea of Apocynum bast, which are in direct contact with liquid containing enzymes, are cuticle and lignin, respectively. These compact structures result in high hydrophobicity and low accessibiliyt. Apocynum bast has certain antibacterial activities against E.coli  and S. aureus of 22% and 14%. So, a multi-level recalcitrance structure of Apocynum bast to biodegumming puocess is constituted by high gum substance proportion, special ultrastructure and the existence of antibacterial component.

Key words: Apocynum, biodegumming, bio-recalcitrance, phloem tissue, antibacterial rate