Characterisation and antifungal activity of extracellular chitinase from a biocontrol fungus, Trichoderma asperellum PQ34 Article Swipe
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· 2019
· Open Access
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· DOI: https://doi.org/10.1080/21501203.2019.1703839
· OA: W2996678343
<i>Trichoderma</i> species were known as biological control agents against phytopathogenic fungi because they produce a variety of chitinases. Chitinases are hydrolytic enzymes that break down glycosidic bonds in chitin, a major component of the cell walls of fungi. The present study shows that extracellular chitinase activity reached a maximum value of approximately 22 U/mL after 96 h of <i>T. asperellum</i> PQ34 strain culture. The optimal temperature and pH of enzyme are 40°C and 7, respectively, whereas the thermal and pH stability range from 25°C to 50°C and 4 to 10, respectively. Chitinase at 60 U/mL inhibited nearly completely <i>in vitro</i> growth of <i>Colletotrichum</i> sp. (about 95%) and <i>Sclerotium rolfsii</i> (about 97%). In peanut plants, 20 U/mL of chitinase significantly reduced the incidence of <i>S. rolfsii</i> infection compared to controls. The fungal infection incidence of seeds before germination and 30 days after germination was only 2.22% and 2.38%, while the control was 13.33% and 17.95%. Besides, chitinase from <i>T. asperellum</i> PQ34 can also prevent anthracnose that is caused by <i>Colletotrichum</i> sp. on both mango and chilli fruits up to 72 h after enzyme pre-treatment at 40 U/mL. In mango and chilli fruits infected with anthracnose, 40 U/mL dose of chitinase inhibited the growth of fungi after 96 h of treatment, the diameter of lesion was only 0.88 cm for mango and 1.45 cm for chilli, while the control was 1.67 cm and 2.85 cm, respectively.
