Abstract:
Fungi were isolated from agricultural soil and plant specimens. Twenty three isolates from 44 fungal isolates were found to produce cutinase by using PCL-plate clearing assay and their cutinase activity were investigated. All the cutinase-producing fungi were cultured in liquid mineral medium (LMM) containing PCL or crude cutin extracted from papaya peels, which was a carbon source for cutinase production. Cutinase activity was assayed base on the hydrolysis of paranitrophenyl butarate (p-NPB). It was found that PBURU-T5 gave the highest cutinase activity. The isolate PBURU-T5 was selected for identification based on morphology together with comparative nucleotide sequencing from internal transcribed spacer region of the ribosomal RNA gene (rDNA-ITS) and it was identified as Fusarium falciforme. The optimum conditions for the production of cutinase from F. falciforme PBURU-T5, showed that the culture medium with initial pH at 7.0, incubation temperature 30 °C at 150 rpm with the optimal medium composition consisting of 2.5 g/L cutin extract from papaya peels as a carbon source, 4 g/L peptone as nitrogen source by harvesting on 4 days of incubation provided the highest cutinase activity of 4±0.15 U/ml. The crude cutinase showed the highest enzyme activity at pH 9.0 and temperature 35 °C. For the detergent application, cutinase enzyme (powder form) from F. falciforme PBURU-T5 was mixed with a commercial detergent and was used for oily stain and pill/fuzz removal from spun-polyester fabrics through laundry. Then, the fabric was measured for color values, analyzed for pilling rate, and tested for weight loss and bursting strength loss. When the weight ratio of detergent: enzyme at 1:0.1 was used for fabric washing, oily stain could be completely removed in one washing cycle while fuzzy hair and pill was removed to the acceptable pilling rate of 3-4 (from pilling rate of 1 before washing) in eight washing cycles. After washing, fabric lost 2.68 % of its weight and 8 % of its bursting strength which was not a big concern for polyester wearers.
