Zahra Vaseghi - Faculty of Chemical Engineering, Biotechnology Research Lab,Noshirvani University of Technology, Babol, Iran
Ghasem D. Najafpour - Faculty of Chemical Engineering, Biotechnology Research Lab,Noshirvani University of Technology, Babol, Iran
Samaneh Mohseni, - Faculty of Chemical Engineering, Biotechnology Research Lab,Noshirvani University of Technology, Babol, Iran
Soleiman Mahjoub - Department of Biochemistry and Biophysics, Faculty of Medicine,Babol University of Medical Sciences, Babol, Iran Fatemeh Zahra Infertility and Reproductive health Research Center, Babol University of Medical Sciences, Babol, Iran

Lipase was produced under desired growth conditions in a novel tray bioreactor using the fungus strain of Rhizopus oryzae. Several agricultural residues/products including sugarcane bagasse, wheat bran,corn meal, barely bran and equal mixtures of sugarcane bagasse with agricultural residues were applied as solidsubstrate. Lipase produced from the pure sugarcane bagasse showed higher activities than other substrates; which resulted enzyme activities of 155.76 and 138.37 U/gds for the top and middle trays respectively. Furthermore, the influence of carbon and nitrogen supplements was investigated. Addition of carbon sourcesas substrate was found to be ineffective, while lipase activity remarkably increased by supplementation ofbagasse with adequate amount of nitrogen source. Among the nitrogen supplements, urea as a suitable nitrogen source was considered; as a result the average lipolytic activity of 229.355 U/gds was achieved. In addition, various concentrations of vegetable oils including canola oil, soybean oil, olive oil and castor oilwere applied. The inducing effect of vegetable oil on lipase activity was investigated. Among them, olive oiland canola oil increased lipolytic activity of lipase with an average value of 192.26 and 183.57 U/gds, respectively.

Lipase; Enzyme activities; Solid state fermentation; Nitrogen sources; Rhizopus oryzae;Ttray bioreactor