The Efficacy of the Seeds of Adansonia digitata L. as a Biocoagulant and Disinfectant in Water Purification

Abstract

Context: Water is an essential commodity for the sustenance of life, yet its availability is drastically reducing due to pollution. The conventional methods used for the treatment of water is relatively expensive and not readily available and hence the need for alternative sustainable means of water treatment. Aim: The aim of the study was to evaluate the efficacy of Adansonia digitata L. seeds as a biocoagulant and disinfectant in the purification of water. Materials and Methods: Dried fruits of A. digitata were collected from the Department of Biological Sciences, Ahmadu Bello University, Zaria. The seeds were excised, washed, sun-dried, powdered and defatted using n-hexane. Synthetic turbid water used for the biocoagulant study was prepared using beneficiated kaolin while that used for disinfection studies was prepared using Escherichia coli isolate. Surface water was also used for the study and was obtained from the Kubanni Reservoir, Ahmadu Bello University, Zaria. The experimental design was complete randomized design (CRD). Experiments were performed in triplicates using 0 mg/L (control), 50 mg/L, 100 mg/L, 150 mg/L and 200 mg/L of A. digitata seed extract. Statistical Analysis: One-way analysis of variance (ANOVA) was used to compare the means of the various parameters measured. Duncan Multiple Range Test (DMRT) was used in separating means where significant. The level of significance was taken at P < 0.05. Results: Results revealed that as a biocoagulant, an optimum dose of 150 mg/L was able to reduce turbidity of synthetic water significantly (P < 0.05) by 96.7% while there was no significant reduction in the turbidity of surface water. As a disinfectant, a dose of 200 mg/L was able to significantly reduce (P < 0.05) the concentration of E. coli of synthetic water from 1.65 × 104 cfu/mL to 5.00 × 102 cfu/mL (97.0%) and that of surface water from 4.27 × 102 cfu/mL to 6.67 × 101 cfu/mL (84.4%). Conclusion: From the investigations done, A. digitata seeds possess biocoagulant and disinfectant potentials, which may be harnessed for water purification.