Date wastes as substrate for the production of alpha-amylase and invertase

ABSTRACT

In Algeria the date wastes production is estimated at least 85.000 tones. Date wastes is an economic source of carbohydrates for conversion to industrial enzymes because it is readily available and relatively low priced. The aim of the present study was to investigate the potential of using date wastes as a substrate for the production of alpha-amylase and invertase. Thirty strains of A. niger were isolated from the saline soils collected from five arid locations in Algeria. The process parameters; time, temperature, sugar content, initial pH, nitrogen source, nitrogen and phosphorus content, in the production of these enzymes were optimized. The obtained results showed the potential of the Aspergillus niger for level productions of these enzymes. For alpha- amylase production, the cumulative effect of fermentation period of 96 h, temperature of 30[degree sign]C, sugar content of 20 g/L, initial pH 5.5, supplemented with yeast extract as nitrogen source, and yeast extract and potassium phosphate at 5.0 g/L, content during the fermentation process of date wastes syrup produced alpha-amylase levels up to 285.6 U/ml. Invertase was produced up to 195.56 U/ml were produced under optimum conditions of 96 h, temperature of 30[degree sign]C, initial pH 6.0, sugars content of 40.0 g/L and the utilization of yeast extract and potassium phosphate at concentrations of 11.0 and 3.5 g/L, respectively. The results obtained, provided evidences, supporting the potential of date waste as suitable source for production of alpha-amylase and invertase at industrial scale