H. Zare; F. Meiguni; G. D. Najafpour
Abstract
Alkaline proteases are the most important groups of commercial enzymes, which have been broadly used in industrial processes. In this study, Bacillus sp. PTCC 1538 was selected as a biological agent to produce alkaline protease. Enzyme production under submerge fermentation using industrial waste effluent ...
Read More
Alkaline proteases are the most important groups of commercial enzymes, which have been broadly used in industrial processes. In this study, Bacillus sp. PTCC 1538 was selected as a biological agent to produce alkaline protease. Enzyme production under submerge fermentation using industrial waste effluent was investigated. Since the costs of the raw material plays an important role in the cost of enzyme production, corn steep liquor (CSL) was selected as a low-cost substrate to reduce the cost of enzyme production. Various carbon sources were used as the auxiliary substrates to enhance enzyme production. Results showed that maximum enzyme activity was obtained when wheat bran was used as an auxiliary substrate. Optimal media composition and growth conditions for alkaline protease production were defined. The optimum conditions were found to be pH 8, incubation temperature of 37 °C, CSL inoculum size of 5 v/v %, yeast extract and wheat bran concentrations of 2 and 6 g/l, respectively. CaCl2 was used as an activator to enhance proteolytic activity of the enzyme. Under optimum condition, enzyme activity of 100.7 U/ml was obtained at CaCl2 concentration of 1.5 g/l.
J. M. Patra; S. S. Panda; N. K. Dhal
Abstract
Citrus fruits world production is estimated to be over 88 million tons per year, and oranges alone account for about 55% of such amount. Orange peel waste (OPW) is the solid residue of membranes, cores, juice sacs, etc which represents over 50% of the processed fruits. Its disposal is of great concern ...
Read More
Citrus fruits world production is estimated to be over 88 million tons per year, and oranges alone account for about 55% of such amount. Orange peel waste (OPW) is the solid residue of membranes, cores, juice sacs, etc which represents over 50% of the processed fruits. Its disposal is of great concern from the environmental point of view. Due to the large availability and composition rich in the present investigation was focused on the production of ethanol from OPW which will be an economic, environmental friendly and efficient approach. Strains of Aspergillus niger and Saccharamyces cerevisiae was used for hydrolysis and fermentation of pretreated orange waste, respectively. Spectrometry scanning electron microscopy (SEM) and Fourier transformation infrared (FTIR) were used to characterize the sample. Sugar percentage was found to be 3.64 in pretreated sample after 24 hours, which is responsible for the yield of ethanol (6.17 v/v). The results indicated that orange peel can be used as a good low cost alternative feedstock for ethanol production.