Browsing by Author "Usman, L.A"
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Item Bioactive Metabolites in improved cowpea seeds(2005-06) Ameen, O.M; Fatope, O.M.; Usman, L.A; Adebayo, S.AThe International Institute of Tropical Agriculture (IITA) has developed some pest and disease resistant cowpeas. From these, the seeds of 8 cowpea cultivars were extracted with ethanol, and partitioned into chloroform and water-soluble fractions, the water-soluble fraction was further extracted with ethyl acetate. Residues from ethanol, chloroform and ethyl acetate soluble fractions for each of the 8 cowpea cultivars were screened against brine shrimp larvae. The see extracts of cowpea cultivars IT93K-596-9-12, IT90K-277-2 and IT93K – 452 – 1 were found to be most active, indicating that they contain cytotoxic compound(s).Item Chemical Composition of Leaf Essential Oil of Annona senegalensis Pers. (Annonaceae) growing in North Central Nigeria(2010) Ameen, O.M; Usman, L.A; Oganija, F.S.; Hamid, A.A.; Muhammed, N.O; Zubair, M.F.; Adebayo, S.ALeaf essential oil of Annona senegalensis Pers. obtained by hydrodistillation was analysed using GC and GC/MS. The analyses revealed the abundance of oxygenated monoterpenes (65.0%). The major constituents were citronellal (30.0%), citronellol (14.8%), geranial (17.2%), thymol (8.1%), β-caryophyllene (7.8%) and carvacrol (6.92).Item Chemical Constituentss of Leaf Essential Oil of North-central Nigerian Grown Vitex Agnus-castus I(American-Eurasian Network for Scientific Information, 2010) Hamid, A. A.; Usman, L.A; Adebayo, S.A.; Zubair, M.F; Elaigwu, S.EPulverized leaf of vitex agnus-castus on hydrodistillation, afforded oil in the yield of 0.8%v/w. GC, GC/MS analyses of the oil revealed the abundance of hydrocarbon and oxygenated monoterpenes (53.2 and 24.5% respectively). The major constituents of the oil were; β-pinene (20.0%), viridiflorol (9.8%), α-pinene (9.1%), cis-ocimene (8.4%), 1,8-cineole (6.7%), β-farnesene (5.4%), terpinen-4-ol (4.2%), α-terpineol (4.1%) and β-phellandrene (4.1%).Item Effect of drying on yield, chemical composition, and insecticidal activity of leaf essential oil of sweet orange (Citrus sinensis).(Turkish Chemical Society, Turkey, 2016) Usman, L.APulverized fresh and dried leaves of citrus sinensis (500g) that were dried for five consecutive days during dry season were separately hydro-distilled for 3 hours. Oil yields from samples ranged from 0.1 - 0.37% (w/w). Characterization of the oils using Gas Chromatography-Mass Spectrometry showed that the oil was predominated by monoterpenoids (5.7 - 90.2%). Car-3-ene was the most abundant compound in the oils from fresh and the leaves dried for four days. The insecticidal activity of oils against Callosobruchus maculatus was also determined via contact toxicity bioassay. Regardless of the level of dryness, the oils were observed to be toxic to C. maculatus. Oils obtained from the leaves dried for five days were found to be more active against the insect than other oils.Item Effect on germination and nutrient composition of storing cowpea [Vigna unguiculata(L.) Walp.] seeds in a hermetic atmosphere modified with essential oil vapour from leaves of sweet basil [Ocimumbasilicum(L.)](Faculty of Food and Agriculture, University of the West Indies, Trinidad and Tobago., 2018) Ojumoola, A.O.; Adesiyun, A.A.; Usman, L.ACowpea represents an important staple crop in Sub Saharan Africa and can play significant roles in ensuring food security in that part of the world. During storage, the grains are attacked and decimated by the cowpea bruchid, Callosobruchus maculatus (F). Methods such as hermetic storage and treatment with botanical insecticides have been recommended as safer and cheaper protection alternatives for cowpea grain, than conventional insecticides. When used in combination, these two prove to be faster and more effective in killing resident C. maculatus adults at the commencement of storage and also adults that may later emerge from any parasitized seed in the course of storage. Grains so protected will however be of little value if the germination and nutrient composition of the cowpea seeds are adversely affected by the botanically modified storage atmosphere. In this study, an insecticidal atmosphere within hermetic plastic structures was created using essential oil from leaves of Ocimum basilicum (L.) on filter papers. Cowpea seeds stored hermetically for 30 and 60 days in the presence or absence of the botanically modified atmosphere were subjected to germination tests and proximate analyses. Results showed that the presence of the insecticidal atmosphere during storage did not negatively affect the germination and nutrient composition of the seedsItem Effects of Seasonal Variation on Chemical Constituents and Insecticidal Activity of Leaf Essential Oil of Citrus limonium(Nigerian Society of Biochemistry and Molecular Biology, 2015) Usman, L.A; Olanipekun, B.E; Ismaeel, R.O.; Oguntoye, S.O.; Ojumoola, A.OLeaves (500g) of Citrus limonium harvested in the morning (7.00 am) during dry and rainy seasons were separately hydrodistilled and yielded 0.46 and 0.30 % (w/w) of essential oils. GC and GC-MS analysis revealed that the oils obtained from dry and rainy season harvests were predominated by monoterpenoids (84.2% and 77.2%). The most abundant constituent of the oils from dry and rainy season harvests was; limonene (17.9% and 15.3%). Other principal constituents of the oils were; β-pinene (8.0% and 1.5%), terpinolene (7.0% and 7.1%), citronellal (12.9% and 8.3%), carveol (8.0% and 9.0%), neral (7.9% and 8.5%). citronellol (4.4% and 5.9%) and β-caryophyllene (3.3% and 5.2%). Contact toxicity bioassay was used to investigate the insecticidal activity of the oils against Callosobruchus maculatus. Irrespective of the season of harvest the oils were active against the insect. Interestingly, oils from the two harvests had comparable activity against the adult C. maculatus. Hence, seasonal variation has no significant effect on insecticidal activity of the oil on the postharvest insect pest.Item Fumigant effect of sweet basil (Ocimumbasilicum L) leaf essential oil on the longevity and fecundity of adult cowpea bruchid Callosobruchus maculatus (F) and on germination.(Faculty of Agriculture, University of Ilorin, Nigeria., 2015) Ojumoola, A.O.; Adesiyun, A.A.; Usman, L.AFresh pulverised leaves (00g) of Ocimum basilicum (L) were harvested in July 2014. Essential oil yield from the hydro-distilled leaves after 3 hours was 0.3(w/w) %. GC_MS analysis revealed the predominance of oxygenated monoterpenes (41.0%) in the oil. Terpinen-ol was the major oil constituent accounting for 29.8%. The essential oil (EO) vapour was used to generate an insecticidal atmosphere within airtight fumigation chambers (130mL). Each chamber contained 2 pairs of adult C. maculatus and ten seeds of Ife Brown cowpea variety. The EO was tested at 10, 20, 30 and 40 uL/130mL air. After 24 hours of exposure, the control had the lowest percentage mortality (0.00) while complete mortality was observed in both the 30uL and 40ul doses.Item Influence of three legume seed types on development of Callosobruchus maculatus (F.) and its suceptibility to Azadirachta indica aqueous extracts(Faculty of Agriculture, University of Ilorin, Nigeria, 2018) Ojumoola, A.O.; Bamidele, D.A.; Usman, L.AIn the absence of effective protection, grains of legumes may be completely decimated when attacked in storage by the cowpea bruchid, Callosobruchus maculatus. The use of botanical insecticides has been reported as ecologically innocuous alternatives to conventional insecticides for the control of C. maculatus in stored legume grains. This study thus investigated how legume type influenced the emergence of C. maculatus and its susceptibility to the aqeous extract of neem leaf (a botanical based insecticide). Thirty (30) C. maculatus adults from the same population were reared for 4 generations on improved varieties of cowpea (IT89KD391), mung bean (NM 92) and soybean (TGX 1448) seeds under laboratory conditions. While both cowpea and mung bean supported the emergence of adult C. maculatus in all the four filial generations studied, emergence in soybean terminated after first filial generation. Susceptibility of fourth filial generation adult beetles from cowpea and mung bean to neem leaves aqueous extracts was subsequently tested by contact application. Treated adult C. maculatus of the mung bean line were found to be significantly (P<0.05) more susceptible to the botanical extract than those of the cowpea line. It was thus concluded that cowpea and mung bean seeds are more suitable for the emergence of adult C. maculatus than soybean seeds and that its management in storage with neem leaves aqueous extract should be done bearing in mind that the type of legume being treated might influence the effectiveness of the botanical insecticide.Item Levels of ammonia-nitrogen, carbo dioxide, dissolved oxygen, and biochemical oxygen demand in Asa river, Ilorin, Nigeria(Faculty of Pure and Applied Sciences, LAUTECH., 2009) Adebayo, S. A.; Usman, L.AThe impact of municipal and industrial waste discharges into Asa river in Ilorin, Kwara State, Nigeri was investigated. Section of the river along its course within the metropolis were studied by collecting water samples from five different points; Asa Dam, Unity Bridge, Station Bridge, Amilengbe Bridge and Kangile Village. Sample analyses were carried out at monthly interval (April 2008 to March 2009) for a period of twelve months covering both the rainy and dry seasons. Concentrations of ammonia-nitrogen (NH3 - N), carbon dioxide (CO2), dissolved oxygen (DO) and biochemical oxygen demand (BOD5) were determined at each sampling point as measure of organic pollution in the river. The results indicate that the quality of Asa river water was acceptable before entering and after leaving the town but pollution sets in as the river flows through the town indication that the river receives significant inputs of wastes from both domestic and industrial sources. Also, the level of pollution was found to be season dependent. Key: Pollution, river, waste, domestic, industrialItem Susceptibility of the life stages Callosobruchus maculatus (Fabr.) in stored cowpea grains to fumigation with essential oil vapour of Ocimumbasilicum L. leaves.(Faculty of Food and Agriculture, University of the West Indies, Trinidad and Tobago., 2016) Ojumoola, A.O; Adesiyun, A.A.; Usman, L.AThis study was carried out to investigate the susceptibility of the life stages of Callosobruchus maculatus (F.) in stored cowpea to the essential oil vapour of sweet basil, Ocimum basilicum, L.leaves when applied as a fumigant. The extracted and analysed essential oil of O. basilicum leaves in this study was made up mainly of monoterpenoids and sesquiterpenoids with ϒ-terpinene (12.2%), and β-caryophyllene (10.4%) predominating. In separate bioassays, cowpea seeds harbouring the different life stages of C. maculatus were exposed to the oil vapour within a hermetic structure. The essential oil vapour had insecticidal effects on the adults of C. maculatus. Mortality was observed to significantly (P<0.05) increase from 14.8% to 100% as dosage increased from 10μl/80ml air to 60μl/80ml air. Significantly high percentage mortality (98.48%) of C. maculatus eggs was observed after three days of seed fumigation with the essential oil vapour. The percentage mortality caused by the oil vapour to the larval and pupal stages within fumigated cowpea seeds was not significantly different from the control at P=0.05 after three days of fumigation. It was thus concluded that the egg and adult stages of C. maculatus were more susceptible to the essential oil vapour of O. basilicum leaves than the larvae and pupae stages within stored cowpea.