Strain improvement of Trichoderma reesei Rut C-30 for increased cellulase production
The strain of Trichoderma reesei Rut C-30 was subjected to mutation after treatment with N-methyl-N′-nitro-N-nitrosoguanidine (NG) for 6 h followed by UV irradiation for 15 min. Successive mutants showed enhanced cellulase production, clear hydrolysis zone and rapid growth on Avicel-containing plate. Particularly, the mutant NU-6 showed approximately two-fold increases in activity of both FPA and CMCase in shake flask culture when grown on basal medium containing peptone (1%) and wheat bran (1%). The enzyme production was further optimized using eight different media. When a mixture of lactose and yeast cream was used as cellulase inducer, the mutant NU-6 yielded the highest enzyme and cell production with a FPase activity of 6.2 U ml−1, a CMCase activity of 54.2 U ml−1, a β-glucosidase activity of 0.39 U ml−1, and a fungal biomass of 12.6 mg ml−1. It deserved noting that the mutant NU-6 also secreted large amounts of xylanases (291.3 U ml−1). These results suggested that NU-6 should be an attractive producer for both cellulose and xylanase production.
KeywordsCellulase Trichoderma reesei NTG and ultraviolet mutation Fermentation
Unable to display preview. Download preview PDF.
- 2.Galante Y, De Conti A and Monteverdi R (1998) Application of Trichoderma enzymes in the textile industry. In: Harman G. and Kubicek C.(eds.) Trichoderma and Gliocladium. Enzymes, biological control and commercial applications, Vol. 2. pp. 311–326Google Scholar
- 3.Nierstrasz V and Warmoeskerken M (2003) Process engineering and industrial enzyme applications. In: Cavaco-Paulo A. and Gubitz G. (eds.) Textile processing with enzymes. Woodhead Publishing Ltd., England. pp. 120–157Google Scholar
- 7.Zaldivar M, Velasquez JC, Contreras I and Perez LM (2001) Trichoderma aureoviride 7-121, a mutant with enhanced production of lytic enzymes: its potential use in waste cellulose degradation and biocontral. Ele J Biotechnol 1–7Google Scholar
- 9.Pothiraj C, Balaji P and Eyini M (2006) Enhanced production of cellulases by various fungal cultures in solid state fermentation of cassava waste. Afr J Biotechnol 5:1882–1885Google Scholar
- 11.Muthuvelayudham R and Viruthagiri T (2006) Fermentative production and kinetics of cellulose protein on Trichoderma reesei using sugar cane bagasse and rice straw. Afri J Biotechnol 5:1873–1881Google Scholar
- 14.Mendels M, Weber J and Parizek R (1971) Enhanced cellulase production by a mutant of Trichoderma viride. Appl Microbiol 21:152–154Google Scholar
- 15.Johnwesly B, Virupakshi S, Patil GN and Ramalingam Naik GR (2002) Cellulase-free thermostable alkaline xylanases from thermophillic and alkalophillic Bacillus sp. JB-99. J Microbiol Biotechnol 12:153–156Google Scholar
- 29.Mandels M (1975) Cellulose as a chemical and energy source. Biotechnol Bioeng Symp NY 5:81Google Scholar
- 30.Muthuvelayudham R, Viruthagiri T and Selvapandian T (2005) Biosynthesis of cellulase protein on substrates like cellulose, xylose and lactose using Trichoderma reesei. Annamalai Univeristiy. J Eng Technol 118–121Google Scholar