ABSTRACT
Petroleum contain fractions that are potentially toxic, carcinogenic and or mutagenic. Thus the intrinsic biodegradability of petroleum hydrocarbon and distribution in the environment of competent catabolic microorganisms are critical to the implementation of bioremediation strategies for the clean-up of petroleum polluted environments
towards ecosystem and public health preservation. In the present study, the petroleum degrading potentials of bacteria species isolated from petroleum refinery sludge was evaluated. The bacterial species were isolated and identified using standard microbiological techniques. The petroleum degrading potentials of isolates was
determined by a 14-day enrichment assay using basal salt medium (BSM) supplemented with 2% Escravos light crude oil (ELCO) and assessed by gas chromatography (GC). The petroleum degrading isolates were identified as Micrococcus sp., Bacillus sp., Arthrobacter sp., Bacillus sp., Staphylococcus sp. and Streptomyces sp. The mean bacterial counts during enrichment assay ranged between 0.95 × 101 cfu/ml and 9.7 × 101 cfu/ml. Staphylococcus sp. exhibited the highest (96.20%) total petroleum hydrocarbon (TPH) degrading potential; while Micrococcus sp. showed the least
(35.42%) TPH degrading capacity. The isolates were also remarkable in the degradation of polycyclic aromatic hydrocarbon (PAH), removing between 4 and 10 PAH compounds after treatment in the following order (highest to lowest): Staphylococcus sp. >Streptomyces sp. >Arthrobacter sp. >Bacillus sp. >Micrococcus sp. >Bacillus sp.
The study demonstrated that the bacterial isolates were remarkable petroleum degraders with great potentials for deployment as candidates in bioremediation of petroleum polluted sites in the Niger Delta region of Nigeria.
KEYWORDS: Petroleum sludge; Biodegradation; TPH; PAH; Bacteria
ABSTRACT
The use of plant extracts in controlling plant diseases has witnessed appreciable success; such was exploited in this study when efficacy of extracts from Azadirachta indica, Calotropis procera and Anacardium occidentale, each at different concentrations; 30 mg ml-1, 60 mg ml-1, 90 mg ml-1 and 0 mg ml-1 (Control), were examined in vitro to
control Botrytis cinerea that causes damping off disease of Citrullus lanatus var. ‘lanatus’. Result showed that the mean inhibition in colony diameter at 90 mg ml-1 ranged from 0.26-2.26 (A. indica), 0.43-3.30 (C. procera) and 0.13-2.50 (A.occidentale) compared respectively to 0.5-4.36, 0.57-4.33 and 0.43-4.10 in their 0 mg ml-1 concentration. The 90 mg ml-1 concentration that has the least fungal growth evident at different days in all extract used was significantly different (p≤0.05) from the 0 mg ml-1. Furthermore, percentage inhibition in A. occidentale (37.50%) and A. indica (43.33%) were slightly significant (p≤0.05) at 90 mg ml-1 concentration but was significant (p≤0.05) in C. procera (17.50%). From this study, it can therefore be recommended that field trial of these medicinal plants on the control of damping off disease caused by B. cinerea can be achieved as the concentration of the extracts used here increases. Also, the use of these extracts should be inculcated as part of cultural control measure, since they are easy, simple and cost-effective in making.
KEYWORDS: Damping off, Disease control, Fungicidal, Phytochemicals, Methanolic extract, Soil-borne fungi
ABSTRACT
In this study, the microbial flora and sensory characteristics of fresh and salted Vernonia amygdalina leaves were investigated. The leaves were subjected to light salt, light brine, light brine and vinegar and heavy salt treatments for two weeks. Compared with the fresh leaves, all treatments gave leaves with lower pH and bacterial counts. Heavy-
salted and light brine and vinegar treated leaves had the lowest pH and bacterial counts, and gave products containing Lactobacillus and Streptococcus, but devoid of Staphylococcus spp. In addition, they gave leaves with the best organoleptic characteristics, indicating that they were the most effective. The use of salting as a process for the development of value-added products from V. amygalina leaves is discussed.
KEYWORDS: Vernonia amygdalina leaves, salting, bacterial counts, microbial flora, probiotics
ABSTRACT
This study was carried out to evaluate the microbial load and pyhsico-chemical properties of the soil in National Cereal Research Institute rice field, Badeggi, Nigeria. The soil samples collected from fadama, hydromorphic and uncultivated field of NCRI were serially diluted and plated on Potato Dextrose Agar and Nutrient Agar. The incubation was done at 27oC and the associated bacteria and fungi were isolated and enumerated. The physico-chemical properties of the soil were also done. A total of seven (7) bacteria; Echericha coli, Staphylococcus aureus, Enterobacter aerogenes, Chromobacterium sp. Pseudomonas aureginosa, Micrococcus luteus, and Bacillus cereus were isolated and identified. In Fadama, Chromobactreium sp. has the highest percentage frequency (21.89%), Micrococcus luteus in hydromorphic (24.99%) and Pseudomona aerugenosa (23.79%) in uncultivated soil. A total of eight fungi belonging to five general were isolated, identified and characterized to be Aspergillus niger, Ppenicillium sp., Fusarium sp., Rhizopus sp., Aspergillus flavus, Neurospora sitophilia, Mucor sp. and Aspergillus fumigatus. In Fadama, Aspergillus niger has the highest percentage frequency (24.28%) while Aspergillus flavus has the highest percentage frequency (23.70% and 25.07%) in hydromorphic and uncultivated field respectively. The moisture content of Fadama and hydromorphic are 8.80+0.01 and 8.00+0.01 respectively which were significantly different (p<0.05)from Uncultivated soil(3.00+0.01) The results on mineral content of the three soils revealed that the organic carbon, phosphorus, exchange acidity, sand and clay were not significantly different (p>0.05) however, the percentage Nitrogen content were significantly different (p<0.05) with Fadama soil having the highest percentage of (0.43%) from hydromorphic
soil and uncultivated soil which were not significantly different. The calcium, potassium and sodium were significantly different (p<0.05).Therefore, The analysis showed that soil microbes and its physico-chemical properties play very vital role in soil nutrient in rice cultivated field as the uncultivated soil showed less microbial activities and physic-chemical properties hence low nutrients.
KEYWORDS: Fadama, Hydromorphic, Uncultivated, Bacteria, Fungi, Rice field
ABSTRACT
This study examines the long – run stability of an Autoregressive Distributed Lag (ARDL) model with intercept and no constant trend, using quarterly data from CBN annual statistical bulletin that span from 1999Q1 to 2011Q2 and 2000Q1 to 2012Q4. The parameters of the long – run stability of ARDL model are not all statistically significant in their respective p – values and as such cannot be totally relied upon for statistical estimation. Then, we proposed a matrix elimination model which is motivated by the p – values of the respective parameters to systematically eliminate at a time an exogenous variable and its corresponding parameter whose p – value is less significant from the system. Using econometric package (EView), it was investigated that there is collaboration in the long – run stability between the ARDL model and the Binomial coefficient model for different order of n(K). The findings show
that the system (model) now accommodates parameters whose p – values are all statistically significant at 5% level of significance. This now paves way for an extended understanding for decision and policymakers to formulate a mechanism to maintain long – run stability in Foreign Reserves.
KEYWORDS: Binomial coefficients, Econometric View, Diagnostic Stability, Minimum information Criteria, Parsimonious Variables, Over-Parameterization
ABSTRACT
Forty-five (45) samples of prepared burukutu from Kaduna were microbiologically examined for microbial isolates using standard methods. Leaf extract of Gongronema latifolium was obtained using ethanol, hot and cold water as solvents. Phytochemical analysis of the plant was carried out using standard chemical methods. Antimicrobial properties of the extracts were evaluated using agar well diffusion method. The mean bacterial count of burukutu samples ranged from 1.2 ± 0.10 × 106 to 8.3 ± 0.30 ×106 cfu/ml in Kachia, 1.6 ± 0.32 × 106 to 5.1 ± 0.44 × 106 cfu/ml (Kajuru) and 1.4 ± 0.21 × 106 to 7.2 ± 0.40 × 106 cfu/ml in Kudan. The mean fungal count ranged from 1.47 ± 0.31 × 106 to 3.87 ± 0.35 × 106 cfu/ml in Kachia, 1.27 ± 0.12 × 106 to 3.37 ± 0.35 × 106 cfu/ml (Kajuru) and 1.50 ± 0.27 × 106 to 4.00 ± 0.30 × 106 cfu/ml in Kudan. Seven bacterial and four fungal species were identified. The phytochemistry of ethanol extracts of G. latifolium leaves showed phenols had the highest concentration of 15.74 ± 0.03 mg/100g and the least was
anthraquinones (0.87±0.02 mg/100g). The minimum inhibitory concentration (MIC) of the ethanol extract showed that Staphylococcus aureus and Lactobacillus fermentum were most susceptible to the leaf extract of G. latifolium with MIC of 6.25 mg/ml. The leaf extract of G. latifolium have the potential to preserve and extend the shelf-life of burukutu haven inhibited the microorganisms associated with it.
KEYWORDS: Burukutu, Gongronema latifolium, Phytochemical, Proximate
ABSTRACT
Rubber yield has been on the decline and below expectation due to the gap created by lack of extension services delivery. This study examined the awareness level of Agricultural Extension service delivery in rubber production in Edo South ecological zone of Nigeria. The main objective was to determine the respondents’ awareness level of improved technologies and adoption rate. A sample size of 150 farmers was used from the list of rubber farmers obtained from Edo State Ministry of Agriculture and Rural Development and Tree Crop Unit of the Federal Ministry of Agriculture. Valid questionnaire used for the study were 137. A multi-stage sampling technique was adopted for the study. Data collected were analyzed using Frequency distribution, Percentage scores and Linear Regression. The result
of the study indicated, that majority of the respondents (77.0%) were above 41 years of age. Greater proportion of the respondents (82%) had primary school education and could therefore be said to be literate. Most (66%) of the respondents had a household size above 9(nine). Respondent’s contact with Agricultural extension agent was quiet low (18.2%). This means that as much as 76% of the respondents were practically without the necessary information and improve input that could facilitate productivity and improve income which was below N20,000 monthly for more than half of the respondents (55.3%). F value was statistically significant at 5% probability level and the t-value indicated that Ns were not significant. It was recommended that extension delivery should be given adequately priority to empower the farmers to bridge the deficit gap. Regular training should also be organized and more youth should be encouraged to go into rubber production.
KEYWORDS: Extension, Awareness, Rubber farmers, Adoption, Edo South
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ABSTRACT
An increasing interest for global food shortages for the world’s expanding population necessitated the use of agro-waste as food sources or supplement for animal feeds. Candida tropicalis MYA- 3404 was isolated from pineapple fruit waste and identified by both phenotypic and molecular methods. Proximate analysis of three agro-wastes: melon, groundnut and walnut shell was carried out by standard chemical analytical methods. The protein content ranged between 3.73 to 12.14 % with groundnut shell having the highest. The shells contained 61.26 to 65.12 % carbohydrate. The moisture, fibre, ash and lipids were in the range 12.5 to 19.07 %, 6.45 to11.22 %, 1.43 to 6.50 % and 0.43 to 1.14 % respectively. Optimized production of bioprotein by Candida tropicalis MYA- 3404 was at pH 7.0, for 72h. Supplementation with nitrogen sources revealed highest biomass production with yeast extract. The optimization of a combination of carbon sources showed highest biomass production of 0.4640±0.053 mg/l for groundnut shell medium. Using submerged fermentation, maximum yield of cell biomass was produced from groundnut shell followed by melon shell as substrate for fermentation. C. tropicalis MYA 3404 can be used to produce bioprotein from agro-waste as a cheap source of protein in animal feed.
KEYWORDS: Yeast, Shells, Fermentation, Protein
ABSTRACT
Fish farming is a recognized means of livelihood in Nigeria; however, the intensive use of antibiotics to prevent infection and increase fish yield calls for concern. This practice may lead to the growth of antibiotics resistant bacteria which contains resistant genes that can be transferred to human pathogens, causing treatment‐ resistant illness. This study investigated the antibiotics susceptibility profile of bacteria isolated from five fish ponds
in Benin City using standard microbiological procedures. Isolates were identified using morphological characteristics and conventional biochemical tests, while antibiotic susceptibility test was determined by the Kirby-Bauer disc diffusion method. Results showed that total aerobic count of the ponds ranges from minimum 7.85 x 104 cfu/ml recorded in Ekewan fish pond to maximum 135.06 x 104 cfu/ml recorded in Sapele Road fish pond. Bacteria species isolated were Staphylococcus aureus, Bacillus spp and Klebsiella spp, Pseudomonas spp, Proteus spp and E. coli. Frequency of occurrence and percentage distribution of the isolates showed that Bacillus spp had the highest while Klebsiella spp had the lowest. Community fish pond recorded the highest number of isolates while Adesuwa fish pond recorded the lowest number of isolates. Antibiotics susceptibility patterns showed that majority of the isolates were resistant to perfloxacin (85.18%) and amoxicillin (74.81%). It is suggested that the prophylactic and indiscriminate use of antibiotics may be a predisposing factor in the development of antibiotics resistance among the bacteria isolates. This may pose a threat to human population by transferring these resistant genes to other bacteria of human clinical
significance.
KEYWORDS:Bacteria isolates, Susceptibility, Antibiotics, Fish ponds, Frequency
ABSTRACT
This work centers on parametised investigation of the field strength fading characteristics of microcellular wireless LTE channels operating in typical urban terrains. Due to the blockades between the transmitting NodeBs and the mobile station receiver, the fading characteristics of LTE channel are highly stochastic with respect to time or transmitting distance and possesses their own distinctive property. To robustly investigate the field strength fading characteristics, detail drive test measurement has been conducted in five different site locations in waterline area of Port Harcourt City Nigerian at 2.6GHz. From the measured field data, the parametised amplitude of the measured field data is estimated by using the Maximum Likelihood Estimation (MLE) based on different probability distribution functions. The results of the parametised MLE estimate for the acquired field data has been shown, analyzed and reported for each studied location. It is supposed that results of this research this work would serve as a first-hand information for effective communication system design and deployment of future cellular broadband mobile network
in similar radio signal propagation terrains.
KEYWORDS: Fading, Channel, Field strength, Maximum likelihood estimate, Probability distribution function, Broadband networks