ABSTRACT
Aim: Spathodea campanulata is a medicinal plant useful in traditional medicine for the treatment and prevention of some diseases of bacterial and non microbial origins. As a result of this, it becomes very important to investigate the phytochemical and antioxidant (in vitro and in vivo) activities of the plant leaf extracts by chemical methods to ascertain its potential role in folklore medicine. Study Design: In vitro and in vivo by chemical methods. Methodology: 1.5 kg each of S. campanulata air dried leaves ground to powder was extracted separately with ethanol, methanol and petroleum ether at room temperature (25±2°C). Results: The leaf extracts showed qualitatively the presence of saponin, steroid, flavonoids, glycoside, alkaloids, phenol, tannin, terpenoids, phlobatanin and antraquinone. Amount of quantitative phytochemicals screened from the extracts was more in ethanol followed by aqueous, methanol and was least in petroleum ether. Valuable in vitro antioxidant activities were exhibited by the aqueous, ethanol, methanol and petroleum ether extracts in free radical (DPPH), hydroxyl scavenging activities and ferric reducing antioxidant properties. Decrease in values was observed in the in vivo antioxidant assay of glutathione and catalase levels in group of mice infected with Salmonella typhi for three days while there was increase in lipid peroxidation on comparison with negative control value. However improvement in enzymatic antioxidant levels of mice was observed when treated with the plant ethanol leaf extract. The recorded data in the study proposed the use of leaf extract of S. campanulata in traditional medicine hence its inhibition potentials and barrier to generation of free radicals.
ABSTRACT
Production of certain substances that inhibit other microorganisms in the microbial environment of the oral cavity could serve as aggressive by product that may eliminate competitors and pathogens. Hence, this study was carried out to isolate and identify microorganisms from the oral cavity (lower palate of the mouth) and challenge these organisms with some selected strains of pathogenic fungi. The samples were aseptically collected using sterile swab sticks and transported to the Microbiology laboratory, for morphological, biochemical, and antagonistic tests in vitro. Nutrient Agar (NA) and MacConkey Agar (MCA) were used for the isolation of bacteria, Potato Dextrose Agar (PDA) for fungi and Malt Extract Agar (MEA) for antagonistic test. The isolated oral bacteria were Bacillus sp., Lactobacillus sp., Staphylococcus aureus and Streptococcus salivarius. Antagonistic effect was measured by zone of inhibition between the fungal plug and bacterial streak. The inhibition varied with different fungi. Results revealed that there were considerable variations in inhibitory activity. The zone of inhibition was more apparent in Bacillus sp. against Fusarium oxysporum (57.2±0.1: P = .05). There was no inhibition/antagonistic activity with S. aureus and S. salivarius against all the selected fungi (0.0 - 0.1±0.1: P = .05). Antibiotics susceptibility test was carried out on the isolated oral microorganisms. The highest zone of inhibition was found in cotrimoxazole against Lactobacillus (23 mm), while the lowest zone of inhibition was found in ciprofloxacin against Lactobacillus sp. S. salivarius exhibited resistance to all antibiotics (0-12 mm). Bacillus sp., Lactobacillus sp. and S. aureus showed susceptibility to gentamycin. None of the bacterial isolates showed susceptibility to perfloxacin and streptomycin. Hence, gentamycin could be used to treat oral/dental infections caused by these bacterial isolates. Result from preliminary antagonistic studies showed that Bacillus sp. and Lactobacillus sp. could prove to be potent against all selected pathogenic fungi. Therefore, the metabolites produced by these isolates could be further studied for use as biocontrol agents of diseases caused by these fungi.
ABSTRACT
The organic phase of a wide spectrum, antimycotic and diffusable toxin from Erwinia herbicola showed a highly significant inhibitory activity against Pyricularia oryzae spores in spore well bioassay. Germ tube lengths were inhibited more in wells containing 5 microliters equivalent of bacterial toxin than 1 microliter. No significant difference between the germ tube in an equal mixture of Dimethyl sulphoxide: ethanol and controls. Thin layer chromatography using the chloroform extraction of the organic phase showed a significant antagonism on Cladosporium cucumerinum. The retardation factor values for inhibitory zones in solvent 1 were 0.07 for lower spot and 0.26 for upper spot.