Phytochemical and antimicrobial studies of four species of Cola Schott & Endl. (Sterculiaceae)

The in-vitro antimicrobial evaluation of ethanol extracts of four species of Cola Schott & Endl. was done using human isolated strains of Staphylococcus aureus, Staphylococcus albus, Bacillus subtilis, Klebsiella pneumonia, Pseudomonas aeruginosa, Candida albicans, Aspergillus niger as test organisms. The assays were carried out by agar well diffusion, erythromycin and ketoconazole served as the control drugs. The leaf ethanol extracts of the plants were found to be more effective against the tested fungi than the bacteria at high concentrations. None of the extracts was active against Staphylococcus aureus. Plant extract of C. acuminata (P.Beauv.) Schott & Endl. and C. nitida (Vent) Schott & Endl. showed activity on S. albus at concentrations ranging from 10-150 mgmlˉ¹ having comparable diameters of zone of inhibition of 7.3±0.03-16.0±0.0 for C. acuminata and 10.0±0.0-19.0±0.0 for C. nitida. Also, these two species of Cola demonstrated activities on C. albicans and A. niger at concentrations ranging from 90-150mgmlˉ¹ with relatively close diameters of zone of inhibition. Only C. acuminata inhibited the growth of K. pneumoniae at the MIC of 90mgmlˉ¹ whereas, C. albicans was inhibited by C. acuminata, C. millenii K. Schum and C. gigantea A.Chev. at the MIC of 120mgmlˉ¹. Phytochemical screening of the four species of Cola showed the presence of alkaloids, saponins, tannins and cardenolides in all the plants which apart from showing the probable closeness of the species could also be responsible for the observed activities. The antimicrobial property shown by the plant extracts is an evidence of the ethnomedicinal uses of the plants. The similarity observed in the phytochemical constituents and antimicrobial activities demonstrated by C nitida (Vent.) Schott & Endl., C. millenii and C.gigantea A. Chev. and C. acuminata suggest a probable closeness among these species. The results obtained in this study provide preliminary evidence of the chemotaxonomic significance of secondary metabolites and antimicrobial activities in infra-generic taxonomy of species of Cola.Key words: Cola species, Sterculiaceae, phytochemical screening, antimicrobial studies, taxonomy

Environmental Impact Analysis of the Emission from Petroleum Refineries in Nigeria

Health and environmental hazards, a thing of global concern have been the major characteristics of the petroleum refinery areas worldwide, Nigeria inclusive. This is as a result of the emissions from petroleum refineries which resulted into air quality degradation of the host environment. This problem which has equally affected the climatic conditions of the petroleum producing areas is more pronounced in Nigeria due to lack of implementing adequate policies to protect the host environment. This study is carried out to investigate the atmospheric conditions of the petroleum refineries and identify the environmental impact of emissions of criteria pollutants from the proposed project in the area of influence. Emission inventory of criteria pollutants was carried out on the four existing and twenty-three proposed petroleum refineries in Nigeria. Using no control-measure option, the estimated annual criteria air pollutants emissions from point sources in the existing refineries are 1,217 tons/annum for PM10, 45,124 tons/annum for SO2, 167,570 tons/annum for NOx, 3,842 tons/annum for VOC and 242,469 tons/annum for CO. An additional 1,082 tons/annum of PM10, 168,944 tons/annum of SO2, 688,687 tons/annum of NOx, 9,122 tons/annum of VOC and 569,975 tons/annum of CO were predicted to be added into the Nigeria airshed by the proposed petroleum refineries. The highest pollutant emitting state was predicted to be Rivers State with the highest number of refineries while the least pollutant emitting states were predicted to be Kaduna, Edo, Lagos and Anambra States with only one refinery in each of the state. The ability to adopt appropriate control measures will determine the rate of emission of criteria pollutants released into the country’s airshed

From ‘Vagabonds’ to Ethnobotanical Relevance: Weeds of the Campus Sites of Olabisi Onabanjo University, Ago-Iwoye, Nigeria

A survey of the weed flora of the campus sites of the Olabisi Onabanjo University was undertaken. Several visits were made to the disturbed and undisturbed vegetation of the sites for collection of weeds after which the weeds were prepared in accordance with conventional herbarium practice. A total of seventy-three (73) weed species belonging to twenty-seven (27) families were identified and found to be present within the area of study. The family Poaceae seems to have the highest number of weed species (twelve) available within the area followed by Asteraceae with ten (10) species. Amaranthaceae, Cyperaceae and Euphorbiaceae are also in abundance. These weeds have been discovered to be useful, against the mindset of the uninformed that they are useless or ‘vagabond’ plants. Medicinal uses as well as percentage occurrence of each family are presented. From this study it is obvious that the University sites are not only rich in plant biodiversity but that the plants are also very rich in socio-economic values. It is therefore advisable that these plants should be protected from going into extinction so that all would not be lost due to developmental activities

Modeling of Criteria Air Pollutant Emissions from Selected Nigeria Petroleum Refineries

The dispersion models were used to estimate or predict the concentration of air pollutants or toxins emitted from sources such as industrial plants, vehicular traffic or accidental chemical releases. In this study, the Industrial Source Complex Short Term (ISCST3) emission dispersion model was used to measure the ground level concentration of criteria air pollutants within 50 km radius of location. This model considered emissions from major point sources of pollutants in four existing and twenty-three proposed Nigeria petroleum refineries. The obtained ground level concentration for 24-hr averaging periods of the criteria air pollutants at sensitive receptor around each of the refineries was compared with the National Ambient Air Quality Standards (NAAQS) of Nigeria, World Bank and World Health Organization (WHO) to determine their level of compliance. The highest ground level concentration predicted to be 450 - 1875 μg/m3 for 24-h averaging period was obtained at Tonwei Oil Refinery, Ekeremor Local Government, Bayelsa State, while the lowest ground level concentration predicted to be 0.0099 - 0.1 μg/m3 for 24-h averaging period was obtained at Amakpe International Refinery, Eket Local Government, Akwa Ibom State. Percentage set limits of criteria air pollutants ranging from 0.02% to 94.5% are within the set standard limits and no health risk is associated with areas around the plant’s locations while percentage set limits of criteria pollutants ranging from 1.1 to 55.6 folds of the standards exceed the maximum permitted limits, hence affecting areas around the plants. The air quality standards guiding petroleum refinery emissions must be strictly considered, in order to ensure that the ground level concentrations do not exceed the required standard limits and prevent the adverse effects of air pollution in the Nigeria airshed

Quinolone Resistance in Bacterial Isolates from Chicken Carcasses in Abeokuta, Nigeria: A Retrospective Study from 2005-2011

Quinolone resistance in bacteria from food animals is now globally recognized as a serious veterinary and public health problem. To determine the rate of quinolone resistance in pathogenic bacteria isolated from samples from dead chickens submitted for microbiological examination, a six-year retrospective study (April, 2005 – March, 2011) was carried out. Data from records of bacteriological investigations at a Veterinary Teaching Hospital in Nigeria were evaluated. Two hundred bacterial isolates including Escherichia coli (95; 47.5%), Salmonella serotypes (78; 38.0%), Klebsiella (17; 8.5%) and Staphylococcus aureus (12; 6.0%) were isolated from chicken carcasses within the six-year period. On the overall, the isolates were resistant to ciprofloxacin (40.5%), enrofloxacin (21.0%), nalidixic acid (9.5%) and norfloxacin (44.0%). Overall, resistance to quinolones (except nalidixic acid) was highest in S. aureus (ciprofloxacin, 58.3%; enrofloxacin, 33.3%; and norfloxacin, 83.3%) followed by Klebsiella spp (ciprofloxacin, 41.2%; enrofloxacin, 29.4%; and norfloxacin, 64.7%), E. coli (ciprofloxacin, 40.0%; enrofloxacin, 23.2%; and norfloxacin, 41.1%) and least in Salmonella (ciprofloxacin, 38.6%; enrofloxacin,14.5%; and norfloxacin, 36.8%). However, resistance to nalidixic acid was highest in Klebsiella spp (23.5%) followed by S. aureus (16.7%), E. coli (9.5%) and least in Salmonella (5.3%). There was a general decline in quinolone resistance in the last three years (2009-2011) of this investigation. Quinolone resistance in avian pathogenic bacteria could lead to increase in economic loss from bacterial infection and refractory to treatment. Their possible transmission to humans is of public health significance.Keywords: Bacterial isolates, Commercial poultry chickens,QuinoloneresistanceNigerian Veterinary Journal, VOL:33 (2) 483-49

Phytochemical screening, antimicrobial and antioxidant studies of Lannea egregia Engl. and K. Krause (Anacardiaceae) stem bark

Background: A substantial number of drugs are being developed from plants for the treatment of various diseases. Lannea egregia (LE) is a woody perennial plant used traditionally in the management of skin disorders and wounds. Aim: To investigate the biological activities of different solvent extracts of LE bark. Settings: Fresh stem bark of Lannea egregia was collected from Itabo Lanlate, Oyo State, Nigeria. The authentication was done in Forest Herbarium, Ibadan (FHI), Nigeria. The biological activities of the air-dried sample were carried out in the Department of Pharmacognosy, University of Ibadan, Nigeria. Materials and methods: Powdered LE bark sample was extracted by gradient extraction. Phytochemical screening was performed on the extracts using standard procedure. In vitro antimicrobial study was performed on 14 strains of bacteria and 5 fungal strains at a concentration range of 25, 50, 75 and 100 mg/mL of the extract using ciprofloxacin and itraconazole as standard. The minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and minimum fungicidal concentration (MFC) were determined. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity and total phenolic content (TPC) of two active extracts were determined spectrophotometrically. Results: The phytochemical screening of LE revealed the presence of tannins, terpenoids, flavonoids, anthraquinones, saponins and alkaloids. The dichloromethane (DCM) extract exhibited the highest activity against all the bacterial strains as well as four of the fungal strains. The zones of inhibition (ZI) of bacteria ranged from 9.0 ± 2.0 to 24.6 ± 2.4 mm, MIC of 0.0008 to 12.5 mg/mL and MBC of 25 to 75 mg/mL, while ZI of the fungal strains ranged from 10.3 ± 4.6 to 18.0 ± 5.3 mm, MIC 0.391 – 0.781 and MFC of 50 mg/mL in all the strains. The TPC values of DCM and ethyl acetate (EtOAc) extracts were 1582.47 ± 6.69 and 1579.89 ± 12.77 µg GAE/mg and inhibitory antioxidant activity of 2.54 ± 0.58 and 2.44 ± 0.54, respectively. Conclusion: These findings provide scientific evidence to support the ethnomedicinal use of Lannea egregia bark for treating skin disorders and wounds

Quantification of endogenous phytochemicals and determination of their exogenous effects in somatic embryogenesis pathways of white and water yams

Open Access ArticleIn vitro propagation of yam via organogenesis is constrained with low multiplication rate. Somatic embryogenesis (SE) has shown rapid multiplication potentials in yam. However, it has not been adopted by practical seed system scenarios due to genotype specificity. Reports have shown that SE is regulated endogenously by phytochemicals, but this is yet to be elucidated for yam. This study identified, quantified endogenous, and evaluated effects of exogenous application of selected identified phytochemicals in yam SE. Callus was induced from in vitro axillary bud explants of three Dioscorea rotundata genotypes in Murashige and Skoog (MS) medium containing 9.1 µM 2,4-dichlorophenoxyacetic acid and 5.4 µM naphthaleneacetic acid. Plantlets were regenerated using MS medium containing 4.4 µM benzylaminopurine and 34.0 µM uniconazole-P. Endogenous phytochemicals associated with axillary bud, calluses, and plantlets were identified and quantified using GC/MS. Effect of selected identified phytochemicals on the genotypes was investigated in a 5 × 6 factorial in completely randomized design (r = 3). Data taken on plantlet regeneration was analyzed using ANOVA at α0.05. A total of 27, 22, and 35 phytochemicals were identified in Kpamyo, Ekiti2a, and Asiedu, respectively. Hexamethylcyclotrisiloxane (36.4%, Kpamyo), Tris-tert-butyldimethylsilyloxy-arsane (59.3%, Ekiti2a), and 4-methyl-2-trimethylsililoxy-acetophenone (52.7%, Asiedu) were highest in callus. N-Methyl-1-adamantaneacetamide (31.8%, Kpamyo) and Tris-tert-butyldimethylsilyloxy-arsane (52.7%, Ekiti2a, Asiedu) were highest in plantlets while Tris-tert-butyldimethylsilyloxy-arsane (41.2%, Kpamyo), hexamethylcyclotrisiloxane (55.8%, Ekiti2a), and erythro-9,10-dibromopentacosane (38.9%, Asiedu) were highest in axillary bud. Plantlet regeneration differed significantly among phytochemicals and ranged from 0.7 ± 0.3 (control) to 4.5 ± 0.5 (40.5 µM phenylacetic acid). Also, genotype × phytochemical interactions on number of plantlets regenerated were significant, and mean values ranged from 0.0 ± 0.0 (TDa2014, 4.8 µM decamethyltetrasiloxane) to 7.0 ± 1.7 (TDa2014, 40.5 µM phenylacetic acid). The application of 40.5 µM phenylacetic acid enhanced plantlet regeneration in Kpamyo and TDa2014 by 5.39% and 343.04%, respectively

Gaseous Emission from the Combustion of AGO from the KRPC in Nigeria

Refined petroleum products from Kaduna refinery and petroleum company serves as a source of energy to the nation but gaseous emission from the combustion of these refined products can be harmful to the ecosystem. Gaseous emission from the combustion of AGO of different volumes from Kaduna Refinery was characterized for gaseous air pollutants using the E8500 combustion analyzer. The concentrations for the gaseous emission from the combustion of AGO were 45.84 mg/m3 HC, 16.33 mg/m3 CO, 206.33 mg/m3 NOx for 10 mL. 76.39 mg/m3 HC, 44.33 mg/m3 CO, 689.33 mg/m3 NOx for 20 mL 102.59 mg/m3 HC, 0 mg/m3 CO, 692.67 mg/m3 NOx for 30 ml. 154.97 mg/m3 HC, 0 mg/m3 CO, 1459 mg/m3 NOx for 40 ml. 141.88 mg/m3 HC, 0 mg/m3 CO, 1516.33 mg/m3 NOx, for 50 ml. This study shows that CO and HC exceeded the acceptable limit for stationary sources while NOx and SO2 were below the acceptable limit. Hence, there is a need for rapid response and urgent attention from government and regulatory bodies to put in place policies that will help minimize the effect of these emissions

Ultimate and Elemental Analysis of Some Common Charcoal in Southwestern Nigeria

Common charcoals from different wood species were collected, identified and prepared for analysis. Ultimate and elemental analyses were carried out. In this study, identified charcoal were characterized. The result showed that in the ultimate analysis, Carbon, Hydrogen and Oxygen are the major content of the charcoal samples and are of great importance for the heating value. Sulphur and Nitrogen content were resent in low in quantity. XRF was used in the elemental analysis and the following elements were detected (Na, Cr, Ni, Cd, Al, K, Mn, P, Ca, Si, Mg, Ti, Fe) In the charcoal samples, the percentages of Si and Al are high while the percentages of (Cd, Fe, Na, Ti, Ni, Mg, P, K, Cr) were low. Percentage of silicon was between 50% to 65% in Albizia zygia, Milicia excelsa, Terminalia avicennioides, Funtumia elastica, Milletia thonningii and Hevea brsiliensis with Hevea brasiliensis having the highest which suggested high slagging propensity. Anogeissus leiocarpa, Afzelia bipindensis, Vitellia paradoxum, and Burkea africana have high Na/K. The ratio of Ca/ Mg is greater than 2 in all the samples. LOI ranges from 54.56 – 7.88% with a mean of 25.978±22.909%

ESTIMATION OF EMISSION FACTOR FROM THE COMBUSTION OF AGO, PMS AND DPK FROM THE KADUNA REFINERY AND PETROLEUM COMPANY IN NIGERIA

Air emissions from the combustion of AGO, PMS and DPK were characterized for gaseous air pollutants using an E8500 combustion gas analyzer. The measured concentrations were used to calculate the emission factors of the pollutants. The emission factors for the gaseous emission from AGO were for 10 ml of AGO, HC was 4.584E-05 g/l, CO was 1.633E-05 g/l, NOx was 0.00021 g/l, and zero values were recorded for both CO2 and SO2; for 50 ml of AGO, HC was 0.000142 g/l, NOx was 0.001516 g/l and zero values were recorded for both CO, CO2 and SO2. From PMS were for 10 ml of PMS, HC was 6.9846E-05 g/l, CO was 0.00017 g/l, NOx was 0.00034 g/l, and zero values were recorded for both CO2 and SO2; for 50 ml of PMS, HC was 8.731E-05 g/l, CO was 0.000213 g/l, NOx was 0.0008 g/l, SO2 was 3.76E-06 g/l and CO2 was 0.0066 g/l. From DPK were for 10 ml of DPK, HC was 3.4923E-05 g/l, CO was 2.1667E-05 g/l, NOx was 0.000089 g/l, and zero values were recorded for both CO2 and SO2; for 50 ml of DPK, HC was 6.1115E-05 g/l, CO was 4.0667E-05 g/l, NOx was 0.000191 g/l and SO2 was 2.667E-06 g/l. This study shows that For 10 ml, DPK had the minimum emission factor for HC, AGO had the minimum emission factor for CO, DPK had the minimum emission factor for NOx. For 50 ml, AGO had the minimum emission factor for CO, SO2, DPK had the minimum emission factor for HC, NOx. Therefore, AGO and DPK can act as a source of fuel with the best sustainable environmental effects