Enzymatic processing of plant fibres for diversified uses

Harsh fibre production processes contributing to challenges in the ecosystem have rekindled the interest on green fibres and eco-friendly products globally. This interest has propelled some developing countries, including Swaziland, to explore value addition of naturally available resources for economic gains using eco-friendly processes. Objectives that guided the study were to: determine the effect of enzymes on sisal, century plant and pineapple fibres, determine tensile strength of treated fibres, determine colour of fibres dyed with indigenous dyes, compare the structures of the nonwoven fabrics made from sisal fibres, and to determine the texture of jewelry after applying resins on the product surface. A participatory rural appraisal technique was used to gain insight of the practices and inherent problems in producing craft items. Enzymatic experiments were then conducted to alter fibre physical properties. Findings revealed that crude tedious decortication methods were still used by the fibre processors, and there was a need for product development training to offer different products to what is currently being sold in the market, particularly by the rural associations. When enzymatic treatment was compared with alkali treatment on removal of cementing layers in fibres, alkali performed better than enzymes in removing the lignin, hemicellulose and waxes and lowering the fibre strength. Stress at break for sisal was 0.06 MPa using NaOH and 0.07 MPa when using enzymes. Conversely, pineapple fibres are naturally soft, thus the enzyme treatment did not have a significant effect on the fibre strength. Application of epoxy resin on the sisal jewelry mats did not yield desirable results, thus other resins are to be explored for an acceptable effect to consumers. Subjective assessment of the nonwoven structures showed a softer texture of enzyme treated structures than the control and untreated sisal nonwoven fabrics. Trials on the development of different prototypes showed a great potential if serious efforts are to be made in refining the prototypes. In conclusion, enzymes release fibres from cementing layers although the optimal level is to be ascertained. Fibre strength is reduced with enzyme treatment but pineapple fibres are naturally soft and may not need chemical treatment for craft items. Colour fixation of indigenous dyes on fibres was enhanced with enzyme and alkali treatment. There is a potential for diversifying uses of the investigated leaf fibres but there is need to use intermediate technologies for making a meaningful improvement to products made by rural associations that can infiltrate the current markets.