Effects of Moringa oleifera and Ficus exasperata on Bacteria in Water Samples from Selected Wells in Iworoko-Ekiti, Nigeria

Abstract

This project was designed to assess the effects of Moringa oleifera and Ficus exasperata extracts on pathogenic bacteria associated with selected well waters in Iworoko Ekiti, Nigeria. Well water samples were collected from privately owned students’ hostels at Iworoko-Ekiti, a community located at the fringe of Ado-Ekiti beside Ekiti State University, Ado-Ekiti. Routine bacteriological analyses of the water samples were carried out to determine the load and types of the bacteria present in them. Antibiotic sensitivity pattern of the isolated bacteria was also determined using agar well diffusion method. Assessment of physicochemical parameters (pH, temperature, total dissolved solids, conductivity, turbidity, biochemical oxygen demand , dissolved oxygen) and mineral constituents (Ca2+, Na+, Mg2+, Pb2+, Cu2+ and Cr+) was carried out on the water samples using standard chemical methods. Pathogenic bacterial isolates were challenged with Moringa oleifera and Ficus exasperata leaf extracts in vitro. Extracts with proven efficacy on the bacterial isolates were subsequently tested on them in vivo. The crude extracts were purified using column chromatography and the functional groups of the active phytochemicals were studied using infra-red spectroscopy. The healing effects of the leaf extracts were tested using albino rats. The rats were infected with Escherichia coli and Salmonella typhi and symptoms of their infections namely: loss of appetite, stooling and weakness were watched out for. The infected rats were thereafter treated with specific doses (37.5mg/ml and 75mg/ml) of Moringa oleifera extracts. The blood samples and vital organs (liver, kidney and the intestine) of the experimental rats were subjected to haematological and histopathological analyses. The results of bacterial water analyses revealed that the mean values of total bacterial count and the coliform count ranged from 1.83× 104 cfu/ml to 4.50 × 104 cfu/ml and 1.00 × 104 cfu/ml to 3.17 × 104 cfu/ml respectively. Besides Escherichia coli and Salmonella typhi, other bacterial pathogens isolated 3 from the water samples include Proteus mirabilis, Klebsiella pneumoniae, Staphylococcus aureus, Bacillus substilis and Pseudomonas aeruginosa. Physicochemical tests revealed that total dissolved solids and electrolyte conductivity conformed to the set limits (500mg/ml and 1000us/cm) by World Health Organization. Antibiotics susceptibility test showed zones of inhibition that ranged from 3.33±0.33mm to 28.67+1.15 mm. Crude M. oleifera showed various antibacterial activities against the test pathogenic isolates at different concentrations with zones of inhibition ranging from 1.00±0.0 mm to 10.00±0.58 mm. The purified extracts revealed the presence of OH-/phenol, C-Ostretch and C=Ostretch. The haematological test results showed that infections were established in the experimental rats by the test bacteria as there were increases in lymphocytes and white blood cells (WBC) with a corresponding decrease in packed-cell volume (PCV) in the groups infected but not treated when compared with the control group. However, in the groups infected and treated with different concentrations of the extracts, there was increase in packed-cell volume indicating a sign of health improvement. Histopathological changes such as necrosis of liver hepathocytes, normal intestinal villi with point heamorrhage, and normal renal tubules with point tubular necrosis in the vital organs of the animals were observed in the groups of rats treated with M. oleifera extract. Since the physicochemical assay revealed that water samples are void of heavy chemical pollutants, it is therefore potential chemically good but microbiological unsafe source of water for the populace. The M. oleifera is a medicinal plant that has therapeutic properties that could be harnessed to treat infections caused by E. coli and Sal. typhi in man.