Optimization of exopectinase activity of the fungus Monilia isolated from tangerine in submerged fermentation

Diverse groups of microscopic fungi are able to degrade polymeric plant tissues such as pectin. Biodegradation of these materials are mostly applicable in food industries. In the present study، the exopectinase producing fungus was isolated from decaying tangerine and its exopectinase activity was studied in submerged fermenting condition. Also، the enzyme production of the isolated fungus was compared to the industrial fungus، Aspergillus niger PTCC 5013. The exopectinase production and activity of the extracted enzyme solution with respect to pH، temperature، activity timing and substrate concentration were scrutinized. According to the morphological macroscopic and microscopic features، the isolated fungus was identified as the genus Monilia in the Moniliaceae family. The best exopectinase production was in pH 7 and the best enzyme activity achieved at 50°C، in 30 to 40 minute، 1. 5% substrate and the 1:1 of the enzyme solution to the substrate solution ratio. The isolated fungus، Monilia، was fast growing and produced highly active exopectinase enzyme. In optimum condition، its exopectinase activity was 20 units higher than the fungus Aspergillus niger PTCC 5013. Discussion and The exopectinase enzyme was active in a wide ranges of pH and temperatures. As Monilia does not produce toxic compounds، it is proposed for pectinase production، especially in the food industries.