Effect of fertilizer treatment on the antimicrobial activity of the leaves of Ocimum gratissimum (L.) and Gongronema latifolium (Benth)

The effect of fertilizer treatment on the antimicrobial activity of the leaves of Ocimum gratissimum (L.) and Gongronema latifolium (Benth) was investigated. Cultivated O. gratissimum (L) and G. latifolium were applied with NPK (15:15:15) fertilizer at 100, 200, 300, 400 and 500 kg/ha treatment levels in planting buckets derived using the furrow slice method two months after seedling emergence. No fertilizer treatment served as control. Leaves were harvested one month after treatment. The ethanolic extracts of the harvested leaves were used to determine the sensitivity of the extracts on Klebsiella pneumonia, Escherichia coli, Staphylococcus aurues, Pseudomonas aeruginosa, Salmonella typhi,Streptococcus faecalis, Candida albicans and Aspergillus niger. The result obtained showed that the antimicrobial activity of the leaves of O. gratissimum and G. latifolium was significantly (P < 0.05) increased by fertilizer treatment. The inhibition zone increased with increase in the level of fertilizer treatment. The ethanolic extracts of both plants whether treated or not had no antimicrobial effect on A. niger. This research revealed that fertilizer treatment might have increased the phytochemical content of the leaves of the plants which in turn enhanced their antimicrobial potential.Keywords: Pathogens, NPK fertilizer, ethanolic extracts, inhibition zon

Chemical composition of Hyptis suaveolens and Ocimum gratissimum hybrids from Nigeria

Four medicinal plants belonging to the family Lamiaceae were chemically screened for their chemical constituents including alkaloids, tannins, saponins, flavonoids and phenols. The medicinal plants investigated were Hyptis suaveloens and three putative hybrids of Ocimum gratissimum (Hybrid A, B and C). All the plants contains high percentage yield of crude alkaloids and flavonoids ranging from 10.44 to 14.32% and 9.28 to 12.54%, respectively. Only H. suaveloens is devoid of saponins. Tanninsand phenols were present in all plants. The nutritional values of the phytochemicals were also assessed with a view of establishing and understanding their nutritional uses. The plants contained crude protein(9.19 to 17.94%), crude fibre (4.88 to 9.04%), ash (5.68 to 6.88%), carbohydrate (66.24 to 75.87%), crude lipid (3.48 to 4.90%) and food energy (357.68 to 373.26 mg/cal). The significance of the plants in traditional medicine and the importance of the chemical constituents in the pharmaceutical industries were discusse

Potential use of the Bushmint, Hyptis suaveolens, for the Control of Infestation by the Pink Stalk Borer, Sesamia calamistis on Maize in Southern Benin, West Africa

Maize production in Benin, especially in resource-poor farmers' fields, is constrained by stemborers among other factors. One of the major stemborers in southern Benin is Sesamia calamistis Hampson (Lepidoptera: Noctuidae). African farmers cannot afford to use commercial insecticides for controlling stemborers - they are expensive and unsuitable for durable pest management systems due to eco-toxicity. There is therefore a need for cheaper and environmentally friendly methods and botanicals offer an attractive alternative. The bushmint, Hyptis suaveolens (L.) Poit. (Lamiales: Lamiaceae), was compared with the commercial insecticide Furadan (carbofuran) for the control of S. calamistis on maize Zea mays L. (Poales: Poaceae). Trials were conducted in the screenhouse and in the field during the minor cropping season in 2004 at the International Institute of Tropical Agriculture (IITA)-Benin station. The variables measured included numbers of egg masses per plant, eggs per egg mass (in the screenhouse study), population density of S. calamistis, percentage of infested plants and/or ears, and deadhearts in the field. Irrespective of the variable considered, the aqueous extract of H. suaveolens compared favorably with Furadan while maize surrounded by live H. suaveolens plants had lower S. calamistis densities