Isolation and characterization of amylase from fermented cassava (<i>Manihot esculenta</i> Crantz) wastewater

Abstract

The processing of cassava tubers for the production of nutrient enriched cassava flour, gari and farinha madioca, is usually accompanied with the production of stinking wastewater which usually constitute nuisance to both terrestrial and aquatic life. Thus, this study sought to assess the potential utilization of the wastewater as a source of industrial amylase. Wastewater from cassava mash fermented with pure strains of Saccharomyces cerevisae together with Lactobacillus delbruckii and Lactobacillus coryneformis for 3 days was assayed for amylase activity. The result of the study indicated that the fermentation wastewater had amylase activity, the unit activity and the specific activity of the amylase in the wastewater was 0.22 ìmole/min and 0.06 ìmole/min/mg, respectively. The amylase was purified using gel filtration (Sephadex- G150). The purified enzyme was maximally active at pH 6.0 and 60°C temperature. It had is maximum stability between pH 6 – 7 for 4 h, and 30°C for 50 min. NaCl, NH4Cl, FeCl3, KCl, NaNO3 activates the enzyme activity while CuSO4 and HgCl2 inhibit the activity of the
amylase. It could therefore be concluded that these amylases from the fermented cassava waste water are active at wide temperature and pH ranges. This quality could be explored in the industrial sector
(most especially food industry) as a source of industrial amylase that require a wide range of conditions (temperature and pH).