Extraction, Purification and Characterisation of Plant Enzyme (Calotropain) from the Unripe Pods and Bark of Sodom Apple (Calotropis procera (AIT))
Amoah Ofori Obed
Department of Biochemistry and Biotechnology, KNUST, Kumasi, Ghana.
Hilary D. Zakpaa
Department of Biochemistry and Biotechnology, KNUST, Kumasi, Ghana.
Amoah Theophilus *
Department of Civil and Environmental Engineering, University of Energy and Natural Resources, Sunyani, Ghana.
Saeed Ibn Idris Kofi Yeboah
Department of Civil and Environmental Engineering, University of Energy and Natural Resources, Sunyani, Ghana.
Essandoh Prince
Department of Biochemistry and Biotechnology, KNUST, Kumasi, Ghana.
*Author to whom correspondence should be addressed.
Abstract
Aims: This study was conducted to determine the potential Extraction, Purification and Characterisation of Calotropain from the unripe pods and stem bark of Calotropis procera for establishing its applications in food industry.
Methodology: Crude extracts were purified by ammonium sulphate precipitation and two-step salt precipitation. A One-way ANOVA analysis was used to determine the significant difference between the two methods at 5% significance level.
Results: The results obtained from the study inferred that proteolytic activity was present in both plant part extracts. The protein concentrations of the sample crude extracts were 0.86 mg/ml and 0.92 mg/ml for stem bark and pods respectively. The protein concentrations after ammonium sulphate precipitation were 0.57 mg/ml and 0.69 mg/ml for stem bark and pods respectively. The protein concentrations after two-step salt precipitation were 0.51 mg/ml and 0.61 mg/ml for stem bark and pods respectively. Proteolytic activities of the crude enzyme extracts were 0.038 µmol/min/ml for stem bark and 0.02 µmol/min/ml for pods. Higher values of 0.075 µmol/min/ml and 0.05 µmol/min/ml were calculated for the enzyme extracts for stem bark and unripe pods respectively after ammonium sulphate precipitation and after two-step salt precipitation. The enzyme extracts for stem bark and pods respectively recorded proteolytic activities of 0.099 µmol/min/ml and 0.07 µmol/min/ml.
Conclusion: The outcome of this study showed how the proteolytic activities of the plant parts could be enhanced for protein hydrolytic processes in the production of food.
Keywords: Calotropis procera, calotropain, proteolytic activity, ammonium sulphate precipitation, two-step salt precipitation