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- ItemOpen AccessThe amino acid profiles of the yolk and albumen of domestic duck (Anas platyrhynchos) egg consumed in Nigeria(Elixir Food Sciences, 2012-11-06) Adeyeye, E.I; Adebayo, W.B; Ayejuyo, O.OThe amino acid composition of the yolk and albumen of the egg of domestic duck was determined on a dry weight basis. The total essential amino acid ranged from (g/100 g crude protein, cp): 40.9-41.3 or from 43.5-47.8 % respectively of the total amino acid. The amino acid scores showed lysine ranged from 1.26 -1.27 (on provisional essential amino acid scoring pattern) and 1.19-1.21 (on suggested requirement of the essential amino acid of a pre-school child). The predicted protein efficiency ratio was 2.33-2.52, the essential amino acid index range was 1.31-1.32 and the calculated isoelectric point range was 4.90-5.53. The Leu/Ile ratio range was 1.80-1.38. The correlation coefficient (rxy) was positive and significant at r = 0.05 for the amino acids, amino acid scores (on suggested requirement of the essential amino acid of a pre-school child) and the isoelectric point in the two samples. Domestic duck yolk and albumen amino acids were compared with yolk and albumen of domestic guinea fowl and domestic chicken eggs.
- ItemOpen AccessAnalysis of Antibiotics in poultry wastewater and droppings using solid phase extraction and High Performance Liquid Chromatography(Chemical Society of Nigeria, 2016) Oluseyi, T.O.; Oyeyiola, A.O.; Rabiu, B.; Mbadiwe, N.; Olayinka, K.O.; Silva, B.O.A method was developed for the extraction, pre-concentration and analysis of two antibiotics Amoxicillin (AMOX) and Oxytetracycline (OXY)) in poultry waste water and droppings. The method was based on solid phase extraction (SPE) and high performance liquid chromatography with ultraviolet detection (HPLC-UV). Optimization of the chromatographic conditions and the conditioning of the SPE sorbents were carried out to obtain the optimal condition for the analysis. Three eluting solvents were tested to establish the optimum conditions for the SPE procedure and pH values of samples were varied prior to HPLC analysis. Methanol gave the best percentage recoveries of 67.61% and 30.98%, followed by acetone with recoveries of 66.32% and 24.31% while acetonitrile had the poorest percentage recoveries of 64.23% and 19.05% for Amoxicillin and Oxytetracycline respectively. In the analysis of poultry waste water and droppings, the matrix components in the samples reduced the extraction efficiency leading to a decrease in the percentage recoveries of samples. The decrease in percentage recoveries obtained for the poultry waste water samples followed the same trend as the standard with methanol giving the best percentage recoveries of 60.27% and 23.04%, followed by acetone with recoveries of 45.37% and 21.65% while acetonitrile gave the poorest percentage recoveries of 29.12% and 16.21% for Amoxicillin and Oxytetracycline respectively.
- ItemOpen AccessAnalysis of antibiotics in poultry wastewater and droppings using solid phase extraction and high performance liquid chromatography(journals.chemsociety.org.ng, 2016-04-30) Oluseyi, T. O.; Oyeyiola, A. O.; Rabiu, B; Mbadiwe, N.; Olayinka, K. O.; Silva, B. O.A method was developed for the extraction, preconcentration and analysis of two antibiotics Amoxicillin (AMOX) and Oxytetracycline (OXY)) in poultry waste water and droppings. The method was based on solid phase extraction (SPE) and high performance liquid chromatography with ultraviolet detection (HPLC-UV). Optimization of the chromatographic conditions and the conditioning of the SPE sorbents were carried out to obtain the optimal condition for the analysis. Three eluting solvents were tested to establish the optimum conditions for the SPE procedure and pH values of samples were varied prior to HPLC analysis. Methanol gave the best percentage recoveries of 67.61% and 30.98%, followed by acetone with recoveries of 66.32% and 24.31% while acetonitrile had the poorest percentage recoveries of 64.23% and 19.05% for Amoxicillin and Oxytetracycline respectively. In the analysis of poultry waste water and droppings, the matrix components in the samples reduced the extraction efficiency leading to a decrease in the percentage recoveries of samples. The decrease in percentage recoveries obtained for the spiked poultry waste water samples followed the same trend as the standard with methanol giving the best percentage recoveries of 60.27% and 23.04%, followed by acetone with recoveries of 45.37% and 21.65% while acetonitrile gave the poorest percentage recoveries of 29.12% and 16.21% for Amoxicillin and Oxytetracycline respectively. The non-spiked poultry wastewater at pH 2.5 had the highest concentration of 19.00 ppm for the AMOX, while at pH 7.0, the lowest concentration of 10.04 ppm was observed, while for the OXY, the only detectable concentration was at pH 9.0, with a value of 6.16ppm.
- ItemOpen AccessAnalysis of Environmental Pollution in a Major Petroleum Depot(Nigerian Journal of Industrial and Systems Studies, 2006) Olowu, R.A; Asapo, E.S; Ayejuyo, O.OThis paper presents a study and possible relationships between some selected heavy metals in Petroleum products, soil, water and plant samples collected from different points around the Nigerian National Petroleum Corporation (NNPC) satellite depot, Ejigbo with samples from Ojo campus of the Lagos State University as the control samples. Cadmium was not detected in water, Ireland control sample but was detected in soil, which ranges from 0.04 ug/g and N.D to 0.80 g in plant samples. Lead was detected in the range of 0.082 ug/L to1.43 mg/L in petroleum products, soil, 0.070 ug/g to 3.2 ug/g and plant, N.D to 0.5 ug/g. The range of Iron in the soil sample was 58.11 ug/g to 122 ug/g, plant 18.72 ug/g to 96.5 ug/g water N.D to 58.11 mg/L as against the control soil 26.0 ug/g to 60.0 ug/g plant 22.4 ug/g to 64.0 ug/g and water N.D to 0.24 mg/l. Zn was detected in the range 14.2 ug/g to 62.0 ug/g in soil samples, plant sample 24.3 ug/g to 88.4 ug/g as against control soil 10.00 ug/g to 21.25 ug/g, plant 11.8 ug/g to 31.6 ug/g and water. These results implied that consumption of food and water within and around such areas might be under threat as there is a gradual accumulation of heavy metals with possible displacement of essential minerals in bio-activities within the consuming organisms which eventually will impact negatively on health and well-being as most of the metals are considered carcinogenic.
- ItemOpen AccessAnalysis of essential oil constituents in hydro-distillates of Calotropis procera(Research Journal of Phytochemistry, 2009) Okiei, W.O.; Ogunlesi, M.; Ofor, E.; Osibote, E.A.The essential oil from the dried leaves of Calotropis procera was analyzed by GC-MS. The three major components in the oil are phytol and its isomers 3, 7, 11, 15-tetramethyl-2-hexadecene-1-ol (37.59%) and 6, 10, 14-trimethyl-2-pentadecanone (15.31%). The essential oil was collected in two modes: one mode is a continuous distillation for 4 h and another mode involves hourly collection of fractions over a period of 4 h, thus providing fractionated samples. This novel procedure makes it possible to identify other components which might not have been detected in the unfractionated sample. Such other components include tetradecanal, isophytol and 1-docosanol. The usefulness of phytol in the management of inflammatory diseases suggests that the plant may be useful in the management of arthritis. 6, 10, 14-trimethyl-2-pentadecanone, a mosquito repellent may be useful for malaria control.
- ItemOpen AccessAnalysis of essential oil constituents in hydro-distillates of Calotropis procera (Ait.) R. Br(Research Journal of Phytochemistry, 2009) Okiei, W.O.; Ogunlesi, M.; Ofor, E.; Osibote, E.A.The essential oil from the dried leaves of Culvtropis procera was analyzed hy GC-MS-The three majot components in the oil are phytol and its isomers 3, 7, 11, 15-teirameihyl-2-hexadecene-l-ol (37.59%) ando, 10J4-trirrœihyl-2-pentadecanone (15, 31%). Tlie essential oil was collected in two modes: one mode is a continuous distillation for 4 h and another mode involves hourly collection of fractions over a period of 4 li, thus providing fractionated samples. This novel procedure makes it possi hie to identify other components which might not have been delected in the utifraclionated sample. Such other components inelude tetradecanal, isophytol and 1-docosanol, The usefulness of phytol in the management of inflammatory diseases suggests that the plant may be useful in the management оГ arthritis, 6, 10, 14-trimethyl-2-peniadecanone. a mosquito repellent may be useful for malaria control.
- ItemOpen AccessAnalysis of Essential Oil from the Stem of Chasmathera dependens.(Journal of Natural Products., 2010) Ogunlesi, M.; Wesley, O.; Ademoye, M.; Osibote, E.A.The essential oil from the stems of Chasmanthera dependens was obtained by hydro-distillation and collected into hexane. Analysis of the oil was carried out on a combined gas chromatograph.mass spectrometer equipped with an HP-5 MS (5% phenylmethsiloxane) capillary column at a temperature programme of 1200C (5 min) increased at 50C /min to 320oC and held for 5 min. Two components n-hexadecanoic acid and oleic acid eluted at retention times 21.413 and 24.308 min respectively amounted to a total concentration of 56.92%. Some other minor components, namely, tetradecanoic acid, 1, 2 benzenedicarboxylic acid butyl-8-methylnonylester, heptadecanoic acid and estra-1, 3, 5(10)-trien-17á-ol, a steroid, were identified. Some of these components have been reported to have antibacterial, antifungal, antiviral and anti-inflammatory activities.
- ItemOpen AccessAnalysis of Locally produced Soap using Sheabutter Oil (SBO) Blended with PalmKernel Oil (PKO)(Nigeria Journal of Science, 2004) Eke, U.B.; Dosumu, O.O.; Oladipo, E.; Agunbiade, F.O.Elevendifferentblends of sheabutter oil (SBO) and palin kernel oil (PKO) were employedin soap production. The 150:350 blend gave best soap judging by TFM while the 350: 150 blend gave a better soap than the former in terms of foam stability. The saponification values of the oils 173.30 (SBO) and 249.18 (PKO), and the iodine values 65.04 (SBO) and 18.58 (PKO) agreed with those found in literature. The unsaponified matter, free fatty acid (FFA) and acid value were found to be 1.23%. 1.713 and 3.60 for PKO and for SBO the corresponding values were 3.60%. 5.4'19 and 11.76 respectively. The results showed that PKO is a purer oil than SBO.
- ItemOpen AccessAnalysis of the essential oil from the dried leaves of Euphorbia hirta Linn (Euphorbiaceae), a potential medication for asthma(African Journal of Biotechnology, 2009-10-23) Ofor, E.; Okiei, W.O.; Ogunlesi, M.; Osibote, E.A.Essential oil was obtained from the dried leaves of Euphorbia hirta, commonly called asthma plant.Analysis of the oil was carried out on a combined gas chromatograph-mass spectrometer fitted with an HP-5 MS (5% phenylmethyl siloxane) column at a temperature programme of 120°C (5 min) increased at 5°C/min to 320°C and held for 5 min. The major components identified include 3,7,11,15-tetramethyl-2-hexadecen-1-ol, 6,10,14-trimethyl-2-pentadecanone, hexadecanal, phytol and n-hexadecanoic acid adding up to 61.01%. Minor constituents include 2-butoxyethanol, tetradecane, phthalic acid, butyl tetradecyl ester, oleic acid, 13-heptadecyn-1-ol, 2-methyl-1-hexadecanol and 1,2-benzene dicarboxylic acid diisooctylester. The possible roles of the components in the treatment of asthma and other diseases are discussed. The oil may function as a repellent against Anopheles species and thus useful for malaria control
- ItemOpen AccessAnalysis of the essential oil from the leaves of Sesamum radiatum, a potential medication for male infertility factor, by gas chromatography - mass spectrometry(African Journal of Biotechnology, 2010-01-14) Ogunlesi, M.; Okiei, W.O.; Osibote, E.A.Essential oil was extracted from the dried leaves of Sesamum radiatum by hydro-distillation and analyzed by combined gas chromatography-mass spectrometry. n-Hexadecanoic acid was found to be the major constituent and with three other fatty acids namely, 9,12,15-octadecanoic acid-(Z,Z,Z), dodecanoic acid and tetradecanoic acid constitute 40.64% of the oil. Other constituents include heptatriacontanol, estra–1,3,5(10)–trien-17á-ol, 1-(+)–ascorbic acid, 2,6-dihexadecanoate, ethyl isoallocholate, 18,19–secoyohimban–19-oic acid, 16,17,20,21-tetrahydro-16-(hydroxymethyl)-methyl ester, (15á, 16E)-trans-(2,3-diphenylcyclopropyl) methylphenyl sulfoxide, 1,1-[2-methyl-2-(phenylthio) cyclopropylidene]bis-benzene and phenolics. The presence of some of these constituents in the essential oil provides the scientific evidences for the observed cardiovascular and estrogenic activity as well as curative properties of the plant for male infertility factor, constipation, fungal and bacterial infections and bruises
- ItemOpen AccessAnalysis of the essential oil from the leaves of Sesamum radiatum, a potential medication for male infertility factor, by gas chromatography-mass spectrometry(2010) Okiei, W.O.; Osibote, E.A.; Ogunlesi, M.Essential oil was extracted from the dried leaves of Sesamum radiatum by hydro-distillation and analyzed by combined gas chromatography-mass spectrometry. n-Hexadecanoic acid was found to be the major constituent and with three other fatty acids namely, 9,12,15-octadecanoic acid-(Z,Z,Z), dodecanoic acid and tetradecanoic acid constitute 40.64% of the oil. Other constituents include heptatriacontanol, estra–1,3,5(10)–trien-17á-ol, 1-(+)–ascorbic acid, 2,6-dihexadecanoate, ethyl iso- allocholate, 18,19–secoyohimban–19-oic acid, 16,17,20,21-tetrahydro-16-(hydroxymethyl)-methyl ester, (15á, 16E)-trans-(2,3-diphenylcyclopropyl) methylphenyl sulfoxide, 1,1-[2-methyl-2-(phenylthio) cyclopropylidene]bis-benzene and phenolics. The presence of some of these constituents in the essential oil provides the scientific evidences for the observed cardiovascular and estrogenic activity as well as curative properties of the plant for male infertility factor, constipation, fungal and bacterial infections and bruises.
- ItemOpen AccessAnalysis of the watery exudate from the stilt roots of the Umbrella tree, Musanga cercropoides(2003) Ogunlesi, M.; Orebamjo, W.Physico-chemical tests on samples of of the watery exudates collected from the stilt roots of the Umbrella tree, Musanga cercropoides , collected from three locations as well as potable water from Iju Water Works, Lagos during both wet and dry seasons were carried out. Several physicochemical parameters of the exudates were within the W.H.O. limits for potable water and this finding justifies the use of the exudates as drinking water on the farms.
- ItemOpen AccessAnalysis of the watery exudate obtained from the stilt roots of the Umbrella tree Musanga cecropoides(Nigerian Journal of Science, 2003) Ogunlesi, M.; Okiei, W.O.; Kasumu, R.; Orebamjo, T.O.This report contains the results of chemical analysis and phytochemical tests on samples of the watery exudates collected from the stilt roots of Umbrella trees, Musanga cecropoides, at three different locations as well as potable water from Iju Water Works, during both were and dry seasons. The values obtained for the potable water were all within the W.H.O limits. The parameters of the exudates within the W.H.O limits include colour, acidity, conductivity, chloride, sulphate, phosphate, silica, copper and lead while the values for turbidity , pH, total alkalinity, free carbon dioxide, manganese, oxygen, oxygen absirbed KMnO4, salinity and total dissolved solids were outside the limit. A notable feature is the absence of hardness in the exudates. Copper and lead were not detected in all the samples. On freeze-drying the exudates, the brownish residue obtained was found to contain alkaloids
- ItemOpen AccessAnalysis of Underground Water Samples from Polluted Wells in Baruwa Community of Lagos, Nigeria(2009) Ogunlesi, M.; Okiei, W.O.Water is the source of potable water in Baruwa, a suburb of Lagos, Nigeria. In 1994, some reddish non-polar liquid was found in one well and thereafter in several other wells in Baruwa. The pollutant was suspected to be due to leakage of petroleum products from nearby pipelines. Samples of liquids from fifteen wells in Baruwa were collected over a three-month period and the ratios of non-polar liquids: water (volume:volume) were determined. The non-polar liquids in the water samples were analysed by distillation and found to contain 60-70% gasoline, 30%-40% kerosene, 5-8% diesel and 1.2-2% residue. Infra-red spectra of the non-polar liquid was similar to that of premium motor spirit. The environmental and health effects of such pollution is discussed. Routine monitoring of well waters in close proximity to petroleum pipelines is suggested
- ItemOpen AccessAncistroguineines A and B as well as ancistrotectorine-naphthylisoquinoline alkaloids from Ancistrocladus guineënsis(1998-04) Bringmann, G.; Gonther, C.; Busemann, S.; Schaffer, M.; Olowokudejo, J.D.; Alo, B.I.The isolation of three naphthylisoquinoline alkaloids from the leaves of Ancistrocladus guineënsis is described. Their complete structures were established by spectroscopic, chiroptical and degradative methods. Thus, two hitherto unknown 5,8′-coupled naphthylisoquinolines, named ancistroguineines A and B, were isolated, constituting the first example of a pair of 3-epimeric naphthylisoquinoline alkaloids. Moreover, ancistrotectorine, a 7,3′-coupled alkaloid previously known only from the South-East Asian species Ancistrocladus tectorius, was isolated. Its absolute stereostructure was confirmed by oxidative degradation and by comparison of experimental and calculated CD spectra.
- ItemOpen AccessAnilinolysis of nitro‐substituted diphenyl ethers in acetonitrile: The effect of some ortho‐substituents on the mechanism of SNAr reactions(Wiley, 2009-11-11) Isanbor, C.; Emokpae, T.A.Rate data are reported for the reactions of a series of X‐phenyl 2,4,6‐trinitrophenyl ethers 1a–e[X = H, 4‐NO2, 2‐NO2, 2,4‐(NO2)2, or 2,6‐(NO2)2] with substituted anilines 2a–e [Y = H, 2‐CH3, 2,4‐(CH3)2, 2,6‐(CH3)2, or N‐CH3] in acetonitrile as solvent. For individual amine, kinetic data show that there is little steric hindrance to attack at the 1‐position of the parent molecules, even in the presence of di‐ortho substitution. With each substrate, however, there is evidence for significant steric interactions; such effects leading to rate retardation were very severe for 2,6‐dimethylaniline 2d (2,6‐(CH3)2) and N‐methylaniline 2e (Y = N‐CH3), the deactivating effect of N‐CH3 in most cases is slightly higher than that of 2,6‐(CH3)2. However, the reactions with 2e are base catalyzed whereas those of 2d are not. The corresponding reactions with aniline 2a (Y = H) and mono‐ortho methyl‐substituted aniline 2b (Y = CH3) are wholly base catalyzed. Only with the dinitro substrates, an uncatalyzed reaction is observed and when X = 2,6‐(NO2)2 this pathway takes all the reaction flux. A rationale is provided for the dichotomy of amine effects observed in this investigation. © 2009 Wiley Periodicals, Inc. Int J Chem Kinet 42: 37–49, 2010
- ItemOpen AccessAnthropogenic activities impacts on atmospheric environmental quality in a gas-flaring community: Application of Fuzzy Logic Modelling concept.(Springer, 2018) Akintola, O.A., Sangodoyin, A.Y., Agunbiade, F.OWe present a modelling concept for evaluating the impacts of anthropogenic activities suspected to be from gas flaring on the quality of the atmosphere using domestic roof-harvested rainwater (DRHRW) as indicator. We analysed seven metals (Cu, Cd, Pb, Zn, Fe, Ca, and Mg) and six water quality parameters (acidity, PO43−, SO42−, NO3−, Cl−, and pH). These were used as input parameters in 12 sampling points from gas-flaring environments (Port Harcourt, Nigeria) using Ibadan as reference. We formulated the results of these input parameters into membership function fuzzy matrices based on four degrees of impact: extremely high, high, medium, and low, using regulatory limits as criteria. We generated indices that classified the degree of anthropogenic activity impact on the sites from the product membership function matrices and weight matrices, with investigated (gas-flaring) environment as between medium and high impact compared to those from reference (residential) environment that was classified as between low and medium impact. Major contaminants of concern found in the harvested rainwater were Pb and Cd. There is also the urgent need to stop gas-flaring activities in Port Harcourt area in particular and Niger Delta region of Nigeria in general, so as to minimise the untold health hazard that people living in the area are currently faced with. The fuzzy methodology presented has also indicated that the water cannot safely support potable uses and should not be consumed without purification due to the impact of anthropogenic activities in the area but may be useful for other domestic purposes.
- ItemOpen AccessAntimicrobial activity of the essential oil and the fractional samples obtained from the leaves and seeds of Phyllanthus amarus (Euphorbiaceae)(2009) Ogunlesi, M.; Okiei, W.O.; Osibote, E.A.; Muotoh, C.The aim of this study is to investigate the alleged antimicrobial activity of P. amarus. Fresh leaves and seeds of the plant were air-dried, pulverized and the essential oil extracted into hexane by hydrodistillation over a period of 4 h. In addition, hourly fractions were collected and sensitivity tests were carried out on twelve microorganisms including yeast, Gram-positive and Gram-negative bacteria. All the samples of essential oil and fractions demonstrated activity against the microorganisms except Pseudomonas aeruginosa. The activity of the essential oil collected over 4 h exceeded that of the control 0.05% ciprofloxacin, for Staphylococcus aureus (isolate) and Bacillus subtilis. The results indicate the use of the plant as an antimicrobial. Thus, there is scientific basis for the use of the plant in the treatment of bacterial and fungal diseases.
- ItemOpen AccessAntimicrobial activity of the essential oil and the fractional samples obtained from the leaves and seeds of Phyllanthus amarus (Euphorbiaceae).(Research Journal of Phytochemistry, 2009) Ogunlesi, M.; Okiei, W.O.; Osibote, E.A.; Muotoh, C.The aim of this study is to investigate the alleged antimicrobial activity of P. amarus. Fresh leaves and seeds of the plant were air-dried, pulverized and the essential oil extracted into hexane by hydrodistillation over a period of 4 h. ln addition, hourly fractions were collected and sensitivity tests were carried out on twelve microorganisms including yeast, Gram-positive and Gram-negative bacteria. All the samples of essential oil and fractions demonstrated activity against the microorganisms except Pseudomomrs aemginosa. The activity of the essential oil collected over 4 h exceeded that of the control 0.05% ciprofloxacin, for Staphylococcus aureus (isolate) and Bacillus subtilzls. The results indicate the use of the plant as an antimicrobial. Thus, there is scientific basis for the use of the plant in the treatment of bacterial and fungal diseases.
- ItemOpen AccessAntimicrobial activity of the essential oil of Hyptis suaveolens leaves(Elsevier, 1999-03-24) Asekun, O.T.; Ekundayo, O.; Adeniyi, B.AThe essential oil of Hyptis suaveolens leaves showed antibacterial activity at 5 mg/ml concentration against two gram-positive and four gram-negative bacteria.