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Open Access
Molecular identification and safety assessment of microorganisms in okpeye sold in Owerri and Onitsha markets in South-eastern Nigeria
(Federal University of Technology, Owerri, 2004-10) Agunwah, Ijeoma Maureen
Okpeye an indigenous fermented condiment produced from Prosopis africana seeds was assessed to evaluate the microbilogical quality of the condiment. Eighteen (18) commercial samples of okpeye were purchased from six markets in two cities in South Eastern Nigeria. Fifty-nine (59) bacteria colonies were isolated and identified at the species level by phenotyping and sequencing of the 16S rRNA, gyrB and rpoB genes. Bacillus (47.4%) and Staphylococcus (42.3%) were the predominant bacterial species in okpeye. Overall, B. amyloliquefaciens and S. simulans were the most frequently occurring bacteria and were present in all samples. In addition, B. cereus was isolated in samples obtained from all markets. Other bacterial species included B. velezensis, Oceanobacillus caeni, S. cohnii, Escherichia fergusonni and Vagacoccus lutrae. The B. cereus isolates (10) were screened for the presence of 8 enterotoxin genes (hblA, hblC, hblD, nheA, nheB, nheC, cytK, entFM) and one emetic gene (cesB). The non-haemolytic enterotoxin (nhe ABC) and haemolytic enterotoxin (hbl ABD) complexes were present in 70% and 50% of B. cereus respectively. The positive rate of cytK and entFM genes was 70%, while the cesB gene was 30%. The haemolysis test revealed twenty- three isolates out of the twenty-eight isolates tested showing full haemolytic activity on blood agar. Two isolates (O22 and A22) showed partial haemolysis while three (O11, O15 and A12) showed no haemolysis.Antibiotic susceptibility assessment showed that most of the isolates were susceptible to gentamicin, tetracycline, streptomycin, and erythromycin but resistant to ciprofloxacin and vancomycin. These findings highlight the need for further controls to reduce contamination with potential pathogenic bacteria in indigenous fermented condiments such as okpeye. Two isolates that gave the best safety assessment results were used as starter cultures for the fermentation of Prosopis africana seeds. The bacterial load of seeds fermented with the starter cultures was slightly higher than the spontaneously fermented seeds with a value range of (7.7- 9.4 log10 Cfu/g). The seeds fermented with mixed cultures of B. licheniformis and B. amyloliquefaciens had the highest pH (9.14), temperature (39.96oC) and titratable acidity (TTA) (1.03%) after 168 hours of fermentation. The protein, fat, ash and carbohydrate content were higher in okpeye fermented with starter cultures (B, C and D) than that of the commercial samples (E). The spontaneously fermented sample (A) had the highest protein content (27.80%) than all the other samples. The phytochemical composition showed that okpeye fermented with mixed cultures of B. licheniformis and B. amyloliquefaciens had the highest oxalates (11.52%), saponins (0.05%), phytates (549.75 mg/100g), alkaloids (13.03%) and flavonoids (14.20%) than the commercial and spontaneously fermented samples. The spontaneously fermented samples had the highest tannin (13.29 mg/100g) and total phenol (330.36 mg/g) than all the other samples. The commercial sample had the least phytochemical nutrients except for phytate (58.53 mg/100g) and cyanide (1.60 mg/g). The sensory analysis showed that soup cooked with okpeye fermented with mixed cultures of B. licheniformis and B. amyloliquefaciens had the best results in aroma (7.27), flavour(7.40), appearance (7.30), after taste (7.17) and overall acceptability (7.31). The sensory results showed that okpeye fermented with mixed cultures of B. licheniformis and B. amyloliquefaciens was well accepted by consumers. Based on this acceptability as well as the nutritional composition and phytochemical composition, mixed cultures of B. licheniformis and B. amyloliquefaciens c be recommended in the fermentation of P. africana seeds to produce safe and good quality okpeye.
Open Access
Sequestration and dynamic of carbon and nitrogen in soils of dissimilar lithologies under different land use types in Southeastern Nigeria
(Federal University of Technology, Owerri, 2015-06) Ahukaemere, Chioma Mildred.
The study was conducted to determine carbon and nitrogen sequestration and dynamics in soils developed on different parent materials (Coastal Plain Sand, Falsebedded Sandstones and Shale) under different land use types (forest, fallow and cultivated lands) in South-eastern Nigeria. Geology maps were used to guide the location of sampling sites. Three parent materials and three different land use types in each of the parent materials were randomly selected. The study was a three factor experiment laid in a randomized complete block design (RCBD). A total of 27 profile pits were studied. Soil samples were collected from each of the profiles according to their horizons. Undisturbed soil samples for determination of bulk density were collected in core samplers. Small portions of the samples were air dried, crushed and sieved using a 2-mm sieve in preparation for laboratory analyses. Carbon and Nitrogen forms and sequestration, morphological and physico-chemical properties of soils were determined. Data were subjected to ANOVA , multiple regression, coefficient of variation and correlation analyses. From the results, carbon sequestration ranged from 3229 gCm2in Falsebedded sandstone-derived soils to 3648 gCm2 in Shale-derived soils, and did not differ significantly across the soils. Nitrogen sequestration differed significantly (p < 0.001) with soils derived from Coastal plain sands having higher quantity (248.00 gNm-2) while the least was recorded in soils formed from Shale (91 gNm2). The C sequestration capacity of the soils of the different land use types varied significantly (p < 0.05) with fallow soils derived from Falsebedded Sandstone and Coastal plain sand containing the highest quantities (4753 gCm-2 , 4222 gCm-2). Carbon and nitrogen sequestration increased with horizon thickness in all the profiles across the soils studied. The mean total carbon contents ranged from 39.20 to 82.80 gkg-1across the soils and did not follow uniform pattern of distribution down the profiles, except in fallow soils of the Falsebedded Sandstone where it increased with depth. Soils derived from Shale had the least quantity of total carbon while those of Falsebedded Sandstone had the highest value. Forest soils had higher quantity of total carbon (109.20, 42.40 gkg-1) compared to those of fallow and cultivated soils of the Falsebedded sandstone and Shale . Organic carbon constituted about 58% of total carbon in Shale-derived soils, 20.81% in Coastal plain sand and 27.66 % in Falsebedded sandstone –derived soils. In soils of the different land use types, forest soils contained significantly higher proportion of organic carbon, followed by fallow and lastly by those of the cultivated lands. Organic carbon correlated significantly with clay (r = 0.513, 0.578) (p < 0.001), WSA (r = 0.506, 0.626, 0.646) (p < 0.001) and BD (r = - 0.537, - 0.900, -0.736 ) (p < 0.001) respectively. The mean total nitrogen contents of the soils varied from 5.49 - 8.24 mg/kg in soils of dissimilar parent materials, 3.60 - 14.33 mgkg-1, 7.33 – 8.87 mgkg-1, 2.01 – 10.49 mg/kg in soils of the different land use types. Soils formed from Coastal plain sand and Falsebedded sandstone contained significantly higher (p < 0.01) quantity of total nitrogen than those of Shale. In soils of the different land use types, forest soils contained significantly higher (p < 0.001) proportion of total nitrogen (14.33, 10.49 mgkg-1) than fallow and cultivated soils. Soils formed from Falsebedded sandstone and Shale had significantly higher (p < 0.001) proportions of available N compared to those of Coastal plain sand. In soils of the different land use types, forest soils had significantly higher proportion of available N compared to fallow and cultivated soils. Soils developed on different parent materials under different land use types had varying colour matrix ranges. Soil texture ranged from sand, loamy sand to sandy loam in soils derived from Coastal plain sand and Falsebedded Sandstone, loam, sandy clay loam, silt clay loam to clay in Shalexiiderived soils with soils formed from Shale containing significantly (p < 0.001) higher proportion of clay (263 gkg-1) than those of Falsebedded sandstone (77 gkg-1) and Coastal plain sand (90 gkg-1). The mean bulk density (BD) values ranged from 1.06 to 1.22 gcm-3in soils derived from the three parent materials. Forest soils had the least bulk density values (0.98, 1.09, 1.08 gcm-3) compared to other land uses. In soils of different parent materials, Shale derived soils had highest percentage moisture content (12.49%) while those derived from Falsebedded sandstone had the least amount (9.09%). In soils under the three land use types, forest and fallow soils had significantly higher (p < 0.001) quantity of soil moisture than the cultivated soils. Shale-derived soils had significantly higher (p < 0.001) stable aggregates (29.23%, 1.35 mm) than those derived from Coastal plain sand and Falsebedded sandstone. In soils of the varying land uses, soils of the forest had significantly higher (p < 0.001) stable aggregates compared to those of fallow and cultivated lands. Soils were slightly acidic across the parent materials and land use types. Significantly (p < 0.01) least proportion of Calcium (Ca) (2.76 cmolkg-1) was recorded in soils of the Falsebedded sandstones while those developed on Shale had the highest quantity (4.28 cmolkg-1). Significantly higher percentage base saturation was obtained in soils derived from Shale (91.4%) while the least value was obtained in Falsebedded sandstone-derived soils (68.71%). Taxonomic classification was done to the Subgroup level. The soil classes derived from soil taxonomic classification of the USDA was correlated with the World Reference Base. Soils were classified as Grossarenic Kandiudults (USDA), Chromic Acrisols (WRB), Typic Kandiudults (USDA), Rhodic Acrisols (WRB), Lithic Kanhapludults (USDA), Rhodic Acrisols (WRB), Arenic Kandiudults (USDA), Chromic Acrisols (WRB), Vertic Paleudults (USDA), Haplic Acrisols (WRB), Entic Paleudults (USDA), Haplic Acrisols (WRB), Psammentic Hapludults (USDA), Arenic Acrisols (WRB)
Open Access
Application of deterministic and stoichastic analysis of fault seal integrity in Baka Field, Niger Delta
(Federal University of Technology, Owerri, 2015-12) Njoku, Ikechukwu Onyema
Fault seal analysis in fault dependent reservoirs were carried out at different reservoir levels in the Baka Field, Niger Delta. These involved stratigraphic correlation, 3-D seismic interpretation of faults and horizons, time-depth conversion of all interpreted faults and structural maps using both check-shot and synthetic seismogram. Also, static models of all interpreted reservoir levels, and 3-D deterministic and stochastic fault seal integrity models were carried out. The deterministic approach applied in this study is sensitive to uncertainties associated with mapping of horizons in the proximity of faults and the inherent uncertainties in the static fault interpretation in both position and fault zone properties complexity. However, the integration of stochastic approach captured the uncertainties in the position of the reservoirs at all interpreted faults by allowing multiple realizations of stacking geometries relative to their lateral reservoir distribution. All hydrocarbon bearing reservoir levels and faults were interpreted in detail on seismic and a structural framework model was built for juxtaposition analysis and fault shale gouge ratio calculation. The interpreted hydrocarbon columns of the reservoirs in the field are mostly controlled by structural spill points, implying that the faults affecting the accumulation must be effectively sealed which is evident from calculated high SGR values. Some reservoirs are under filled, indicating that the faults are leaking. It was shown that these fault intervals have relatively low SGR. There is high degree of conformity between field hydrocarbon column heights and the stochastic column heights predicted from the shale gouge ratio. The calculated shale gouge ratio quite matched with the shale gouge ratio related column height distribution used in exploration. Top shale thickness played a role (impede up dip fluid conduit), but not a major factor in the Baka reservoirs as regards to column controls. Also, faults in the Baka Field leaks at <20% shale gouge ratio with varying weak points, mainly 20 – 35% shale gouge ratio and more. Good fault seal capacity exists in the Baka Field at >40% shale gouge ratio. Shale gouge ratios are higher at the boundary fault.
Open Access
Effect of processing and storage on the retention of flavour compounds in Piper nigrum L. and Aframomum danielli spice sample
(Federal University of Technology, Owerri, 2018-07) Adedokun, Isiaka Ishola
Effects of processing and storage on the retention of flavour compounds in Piper nigrum L(‘black pepper’) and Aframomum danielli seeds spice samples was studied. Mature berries of Piper nigrum L. and pods of Aframomum danielli were procured from point of harvest and subjected to post-harvest treatment and dried respectively. Dried spice seeds were pulverize into powder prior to extraction of flavour compounds with six different solvents. The solvent extraction process was at 1:5w/v ratio of spice powder to solvent and the extract was vaporized to obtain 1:1w/v flavour extract from each solvent for preliminary investigation of flavour constituents. Three processing methods were applied for each spice: (i) pulverized sample, (ii)extract with aqueous 40% ethanol sample and (iii) ethanol extract-coated on suitable carriers(potato grits and rice grits). The pulverized and 40% ethanol extract were stored in amber coloured glass bottles while extract on suitable carriers were packaged in high density polyethylene bags. Each sample was stored at ambient temperature (30+ 3o C) for six months and analyzed at intervals. GC-MS was used to determine the chemical constituents and to monitor the flavour profile during storage. The results of moisture content, specific gravity, phytochemicals and flavour compounds in solvent extract samples were significantly (p<0.05) varied. Specific gravity of absolute ethanol flavour extract was 0.784 in Piper nigrum L. and 0.612 in Aframomum danielli and were significantly higher (p<0.05) than other solvent samples. In Piper nigrum L. n-hexane flavour extract showed 86 GC-MS peaks and 30 Major Flavour Principles (MFPs). This was followed by acetone extract with 78 GC-MS peaks and 26 MFPs. GC-MS peaks of 56 with 18 MFPs in absolute ethanol, 59 GC-MS peaks with 25MFPs in 40% ethanol extract, 42 GC-MS peaks with 20 MFPs in methanol and water extract had the least 5 peaks and 3MFPs. Piperine was the high major flavour principles (MFPs) in Piper nigrum L. flavour and the values ranged from 2.43% in hexane extract to 17.50% in ethanol extract. However 10 GCMS peaks and 8 MFPs were found in absolute ethanol extract of Aframomum danielli, 9 GC-MS peaks and 7 MFPs in 40% ethanol extract sample, 22 GC-MS peaks and 6 MFPs in methanol sample, 28 GC-MS peaks and 7 MFPs in acetone flavour extract, 84 GC-MS peaks and 12 MFPs in hexane flavour extract and none in water extract of Aframomum danielli. The highest major flavour principle ‘MFPs’ of Aframomum danielli solvent extracts was eucalyptol with values ranging from 20.53% to 62.05%. Percentage retention (PR) of core volatile flavour principles in extract coated in suitable carriers in both spices reduced when the ratios of coating materials (rice grits and potato flour) increased in the encapsulated samples. Furthermore, the percentage retention of core volatile flavour principles in spice products samples studied varied at 6months storage. However 40% ethanol extract of Piper nigrum product sample (PP-EB) had the 91.31% piperine retention higher than other spice products samples in Piper nigrum while pulverized of Aframomum danielli product sample (AFD-PB) showed 83.46% highest eucalyptol retention among Aframomum danielli spice products. Sensory evaluation identified 5 and 8 sensory attributes of Piper nigrum and Aframomum danielli spice flavour product samples respectively. Pearson correlation value of 0.927 in Piper nigrum and 0.671 in Aframomum danielli for flavour pungency was the highest among other sensory attributes to overall acceptability. The total viable counts of fungi and bacteria were higher in raw spices than processed powder. Initial bacterial load was 1.21 x 109 cfu/g in black pepper berries and 7.8 x 108 cfu/g in Aframomum danielli raw seeds. These reduced to 0.9 x 103 cfu/g and 1.21 x 103 cfu/g pulverized spice powder.
Open Access
Assessment of the impact of concessioning on the productivity of Nigerian Ports
(Federal University of Technology, Owerri, 2019-02) Nze, Obiageli Nneka
This study assessed the productivity of Nigerian ports. The study adopted ex post facto design. Using ship traffic, vehicle traffic, berth efficiency, turnaround time as input explanatory variables and output factors as average throughput to compare the pre concession and post concession. The six Nigerian ports: Tincan Island Ports, Apapa Port, Port of Delta Warri, Calabar Port, Rivers Port and Onne Port were sampled. A survey was conducted on 50 stakeholders in the port sector to determine the factors contribute to port’s productivity. These factors were examined for each of the ports under study and were analysed with t-test using a hypothesized mean. Secondary data was extracted from National Bureau of Statistics (NBS) Annual Reports, Nigeria Port Authority (NPA) Annual Reports, and Central Bank of Nigeria (CBN) Annual reports.From the t-test, the factors with p-value less than 0.05 were the significant ones. Among the factors influencing the productivity of the ports in Nigeria are predetermined operational problems, frequent congestion of ship, poor inboard services and high cost of documentation etc. Using Data Envelopment Analysis as the fundamental analytical tool to test the most efficient port before and after the concession period. The result reveals that Onne Port and Tin Can Island Port productivity increased significantly after the concession. However, Rivers, Delta, Calabar and Apapa Ports experienced unstable efficiencies in the post concession era. The implication is that concession of Nigerian Ports have favourable effect on Onne Port and Tin Can Island Port and less favourable to Rivers, Delta, Calabar and Apapa Ports. In line with the result, it was recommended that since it was observed that there was element of improvement in the post-concession period of operation at Nigerian Ports, we recommend adequate provision of superstructure for the private operators to utilized them and compliment their infrastructure with them towards the achievement of goals of concession. However, concessioning is a good instrument to improve productivity in Nigerian Ports and requires continuity among Nigeria Ports. We recommend adequate and necessary cargo handling equipment at Ports that experienced fluctuating efficiency.
Open Access
Effect of sub lethal concentration of glysophate based herbicide on some biochemical parameters of male Clarias gariepinus
(Federal University of Technology, Owerri, 2019-07) Ezema, Joshua Chibueze
The effect of sublethal concentration of glyphosate on some biochemical parameters of male Clarias gariepinus was investigated. Healthy matured (4 months) male Clarias gariepinus were used as test and control organism. The effect on male reproductive hormone (testosterone), thyroid hormone, oxidative stress biomarkers, liver function parameters and haematological parameters were determined. Results obtained revealed that testosterone concentration in exposed groups was significantly (p<0.05) lower than that of Clarias gariepinus in control group. Thyroid stimulating hormone (TSH) and thyroxin (T4) concentration in exposed groups were significantly (p<0.05) higher than that of the control group where as triiodothyronine (T3) concentration in exposed groups were significantly (p<0.05) lower than that of the control group. Malondialdehyde (MDA) concentration of the liver, kidney and gill of exposed fish were significantly (p<0.05) higher than the control group. Glutathione peroxidase (GPx) and superoxide dismutase (SOD) activity in exposed groups were significantly (p<0.05) lower than that of the control group while catalase (CAT) activity was significantly (p<0.05) higher in exposed fish. Lactate dehydrogenase (LDH) activity of the gill of exposed fish was significantly (p<0.05) higher than that of the control group. The exposure of Clarias gariepinus to glyphosate also caused a significant increase in the activity of alkaline phosphatase (ALP), alanine amino transferase (ALT), aspartate amino transferase (AST) and serum bilirubin. The haematological response of Clarias gariepinus exposed to the concentration of glyphosate showed a significant increase in white blood cell count (WBC) and a reduction of erythrocyte count (RBC), haemoglobin (HGB) level, platelet (PLT) and procalcitonin (PCT) concentration of the blood. No significant difference (p<0.05) was observed on LY, MID, GRAM, MCV, HCT, MCH, MCHC, RDWSD, RDWCV, MPV and PDW. This study shows that glyphosate may induce hormonal changes, oxidative stress, hepatoxicity and haematological changes in Clarias gariepinus and therefore should not be used indiscriminately.
Open Access
Predictive modeling and analysis of Nigerian petroleum depletion using a composite underground reservior
(Federal University of Technology, Owerri, 2021-02) Okere, Princewill Chibuzor
The thrust of this study is predictive modeling and analysis of Nigeria’s petroleum resources depletion, using a composite underground reservoir. The Nigerian Petroleum Data from 1957 to 2014, were obtained from the Department of Petroleum Resources (DPR), of the Ministry of Petroleum and Minerals Resources, Lagos Nigeria, which were applied as the experimental data. Predictive models were developed from material balance of Nigerian petroleum resources around a composite underground reservoir. Petroleum depletion models were developed using Hubbert concept, as the input functions were varied, and scatter diagrams of oil and gas production in Nigeria from 1957 to 2014 were plotted using MATLAB 7.9. The models were validated by superimposing them on the scatter diagram profiles of the cumulative data to determine their goodness of fit which were declared by the R-squared (R2 ) produced by the computer software. Hubbert oil depletion concept was employed for the peak determination, dumbbell intersection and establishment of petroleum depletion. Plots of these models were also made to find which models gave almost identical curves as the curves of the plots made from raw data for oil and gas. The models so obtained are all nonlinear equations which have volume as a function of time, and the best chosen to be the forecasting/predictive tool so desired. For the cumulative production and discovery of oil/gas resources, the chosen model 5 obtained is given as V(t) = R 3 (1−𝑒 − 1 𝑅 𝑡 ) + (Vo− R 2 t − R𝑡 2 2 ) 𝑒 − 1 𝑅 𝑡 , and for the annual production and discovery of oil/gas resources, the chosen model 5 obtained is given as P(t) = ( Vo 𝑅 − 𝑡 2 2)𝑒 − 1 𝑅 𝑡 . Based on the peak determinations and dumbbell intersections for the various models, it was found that the Nigerian oil reserve peaked in the year 2008AD (with volume = 28,018.9MMB), and the gas reserve will peak in the year 2065AD (with volume = 2.546 х 106bscf). The Nigerian oil reserve will be exhausted (vol. = 0.136817MMB) in the year 2682AD, while the gas follows suit in the year 3151AD (vol. = 1.62447bscf). The accuracies of these results are based on R2 of 0.9955 - 0.9963 for oil and 0.9979 - 0.9983 for gas. These results clearly show the efficacy of the models so developed, and their reliability in the prediction of Nigeria’s petroleum resources depletion. This result can be used by Nigerian government for planning, diversification of the economy and international bargaining and positioning in OPEC.
Open Access
Comparative analysis of corrosion inhibition effects of esters of castor seed and rubber seed oils in flow pipes
(Federal University of Technology, Owerri, 2021-02) Offurum, Julius Chigozie
Research work on “Comparative analysis of corrosion inhibition effects of ester of castor seed oil (ECSO) and Ester of Rubber Seed Oil (ERSO) in mild steel flow pipes” was carried out. The oil samples were extracted using solvent extraction techniques (n-hexane for castor seed oil and petroleum ether for rubber seed oil). The castor and rubber seeds were ground, and respectively soaked in the n-hexane and petroleum ether before subsequent subjection to soxhlet extraction, to obtain purer oils. The oils were esterified to obtain ECSO and ERSO. Phytochemical analysis of the esterified oils was conducted to reveal the presence of alkaloid, flavonoid, tannins, cardiac glycocide, phenol, phytate, saponin and oxalate that are responsible for protection of the mild steel specimen. The mild steel samples were immersed in a flowing sulphuric acid solution held at various temperatures and pressures. Potentiodynamic polarization was used to determine the influence of the inhibitors on corrosion potential. Scanning electron microscopy provided surface-distorted information about the interaction between the acid medium/inhibitors and the mild steel, while Fourier transform infrared spectroscopy revealed the functional groups present in the inhibitors. The phytochemical evaluation results obtained showed that ECSO has alkaloid value of 2.2%, flavonoid (1.2%), tannic acid (8.6%), cardiac glycocide (7.0%), phenol (0.912mg/100g), Phytate (11.3%), Saponin (1.4%) and Oxalate (12937.5mg/100g), while those of ERSO have values of 2.1%, 43.5%, 12.0%, 28.0%, 1.605mg/100g, 10.8%, 11%, 59062.5mg/100g respectively. Inhibition efficiencies of ERSOtreated dynamic runs at 10g/l, 15g/l, 20g/l concentrations and at all treatment temperatures were higher than those of ECSO; maximum inhibition efficiencies for ERSO and ECSO applications were respectively 64.4% and 34.4% at 50% stroke, 20g/l dosage and 40oC. Furthermore, increase in treatment temperatures and pressures drastically lowered the 22 inhibition efficiency; the results obtained fit the Langmuir model for both inhibitors, with R2 values tending towards unity. Inhibition efficiencies of ERSO-reacted static runs, obtained from potentiodynamic polarization measurements were also higher than those of ECSO, peaking at 81.70% whereas that of ECSO peaked at 75.40%, both for 20g/l treatments at ambient temperature. Scanning electron microscope, SEM pictures of the mildsteel immersed in ECSO and ERSO showed the existence of absorbate species, while Fourier transform infrared spectroscopy, FTIR spectra revealed that there were shifts due to O-H/N-H and C=O stretching frequencies from 3386cm-1 to 3209cm-1 and from 1743cm-1 to 1203cm-1 respectively. The inhibitor samples were able to inhibit mildsteel corrosion substantively, but ERSO gave better corrosion inhibition effects than ECSO.
Open Access
Alkaline and bacterial pretreatment of rice straw and water hyacinth for biogas production in a batch bioreactor
(Federal University of Technology, Owerri, 2021-06) Hans-Anukam, Uzunma Stephanie
The Presence of lignin in lignocellulosic substrates greatly limits anaerobic digestion for production of biogas. The need for initial pretreatment to sufficiently remove it became inevitable. Alkaline and bacterial pretreatment methods were used to pretreat rice straw and water hyacinth samples for application in biogas production in a batch bioreactor. Optimum concentration of NaOH (%), mass of substrate (g) and duration (h) of the pretreatment were studied using Response surface methodology(Box Behnken design) Bacterial spp isolated from termite gut were identified by 16S rRNA gene sequencing and were used for biological pretreatment of the substrate. Each pretreated sample was co- digested with 1:1, 2:1 and 3:1 ratios of cow dung, pig waste and poultry droppings respectively, as amendments. Optimization studies on the biogas production process from the amendment that gave the highest yield in biogas was carried out. Proximate composition ,lignin, cellulose and hemicellulose content of the feedstock was determined by standard methods as well as microbial succession studies .Results obtained showed that 0.5M concentration of NaOH, 14g of sample and 39.5h exposure time were optimum of NaOH pretreatment of the samples which reduced lignin concentrationfrom17.4% to 8.3% and 17.4 % to 7.3% in bacteria pretreated samples while cellulose, reducing sugar and total sugar contents increased from 10.31% to 38.86%, 6.4%to 6.9% and 156.08%to 167.14%respectively, after chemical pretreatment of water hyacinth samples. Lignin and hemicellulose concentrations reduced from 18.01 % to 7.821 % and 11.01 % to 8.21%, while cellulose concentration increased from 10.31 % to 14.40 % after 30 days of bacterial pretreatment of water hyacinth sample. The 16S RNA gene analysis of bacterial consortium from termite gut indicated the presence of Escherichia coli and Morgenela morganii strain S4L2C (MH745964), with 100%and 98.6%similarity, respectively. There was a significant difference (P ≤ 0.05) in biogas yield in all the Alkaline pretreated rice straw (APRS) and Bacteria pretreated rice straw (BPRS) amended with animal manure compared to APRS, BPRS and URS alone. For NaOH pretreated rice straw, best ratio of rice straw to cow dung was 2:1, which yielded 22.51dm3 of biogas. For bacterial pretreated rice straw, 1:1 ratioof rice straw to cow dung was the best combination, which yielded 27.05dm3 of biogas. For bacterial pretreated water hyacinth co-digested with cow dung, highest yield of biogas was recorded in 1:1ratio, with an average of 12.03dm3. Comparative analysis of biogas yield of APRS with BPRS with amendment at varying ratios gave 30.90% increase in biogas yield for APRS and BPRS with cow dung 2:1,45.45% for BPRS and APRS with cow dung 2:1 and 20.30% for APRS and BPRS with cow dung 3:1APRS/BPRS amended with poultry dropping at1:1,2:1and 3:1 recorded 25.01%,42.01%and19.41% respectively while APRS/BPRS amended with pig waste at 1:1,2:1 and 3:1 recorded1.43%, 3.05% and 16.37%.Result indicated that substrate concentration of 520g, Hydraulic Retention Time 22.57 days and cow dung content of 520 g were the optimum conditions with predicted biogas yield of 1.960 x104 ml for bacterial pretreated rice straw. For NaOH pretreated rice straw, 216.7go substrate at HRT of 15.5 days and 520 g of cow dung as amendment were the optimum conditions, with predicted biogas yield of 1.517 x10 4 ml. Concentrations of components gases in biogas produced by rice straw/ cow dung 2:1 which produced highest volume of biogas in this study, were CO1.149%, CO2 13.556% and CH4 64.960% .proximate characteristics of digestate, such as nitrogen, phosphorus and potassium increased, while others including carbon, total solids and total volatile solid content decreased after anaerobic digestion. Finally, microbial load of slurry during digestion decreased during an aerobic digestion from 0, 14 and 28 days. These prove that rice straw and water hyacinth can be used for large-scale biogas production using Response surface methodology (BBD) from the use of bacterial isolate from termite gut which is significantly more effective in pretreatment than 6% NaOH.
Open Access
Biochemical and carcinogenic effects of monosodium glutate and soya bean in wistar rats
(Federal University of Technology, Owerri, 2021-07) Bob Chile-Agada, Adaeze
This study was carried out to investigate the biochemical effects of short, medium and long term administration of monosodium glutamate (MSG) and soya beans in both male and female Wistar rats, using standard methods. LD50 was carried out using rats which led to the choice of 1000, 2000 and 3000 mg/kg b.w for low, medium, and high doses of the samples. A total of 210 (105 males and 105 females) weanly Wistar rats weighing 70 – 78g were divided equally into three groups of 70 rats each representing the various experimental durations (2, 4, and 6 months). Each of these groups containing 70 rats was further divided equally into 14 subgroups, each containing 5 rats. Group 1 and 8 were controls for female and male rats fed normal raw chow and saline. Groups 2-7 (female rats) and 9-14 (male rats) were rats administered low dose (LD), medium dose (MD) and high dose (HD) MSG and soya beans respectively. 6-o-Malonylgenistin (98.47%) and Glycitin (98.11%) were the most abundant oestrogen-like compounds in the dehulled and oil of soya beans. The glucose and insulin levels of both male and female rats were significantly altered by HDs of both MSG and soya beans after 6 months while ALT, ALP and AST levels were significantly elevated after 4 and 6 months following administration of both MSG and soya beans and were more extensive in HD soya bean fed rats. No significant changes (P> 0.05) were observed in the urea levels after 2 and 4 months soya beans respective administration to female and male rats, while HD MSG significantly elevated the creatinine levels of male and female rats after 4 and 6 months administration. Administration of soya beans and MSG for 2 and 4 months had no significant effect (P > 0.05) on the bicarbonate and chloride levels. The HDL levels were significantly reduced while LDL, TC, and TG were significantly (P < 0.05) elevated after 6months HD administration of MSG and soya beans. Soya beans administration produced no significant change in the SOD levels for female rats and catalase levels in male rats after 2 months administration whereas the MD and HD administration of MSG significantly elevated MDA levels of both male and female rats after 4 and 6 months. Two and four months administration of soya beans and MSG produced no significant changes (P > 0.05) in the LH and FSH of female rats while MD and HD of MSG and soyabean significantly decreased the testosterone and LH of male rats. The colorectal, pancreatic, and ovarian cancer markers, and prostate specific antigen levels were significantly elevated after administration of MD and HD of MSG for 2, 4, and 6 months. This study has shown that the high dose administration of monosodium glutamate and soya bean produced delecterious effects on the biochemical parameters and cancer markers on rats after six months extensive administration.
Open Access
Fungitoxity of selected bio-pesticides on the storage rot diseases and biochemical composition of yam varieties (Dioscorea spp) in Owerri
(Federal University of Technology, Owerri, 2021-07) Mba, Paul Chikezie
The study was conducted at the laboratory of Crop Science and Technology, School of Agriculture and Agricultural Technology, Federal University of Technology Owerri between 2017 to 2019.This project evaluated the fungitoxicity of some bio-pesticides on the control of storage rot diseases of yam varieties (D. rotundata and D. alata) especially caused by Aspergillus spp, Fusarium spp, Rhizopus stolonifer, Yeast and B. theobromae. The fungitoxic activity of ethanol extracts of seven plant leaves (used as bio-pesticides); Chromolaena odorata, Carica papaya, Vernonia amygdalina, Ocimum gratissimum, Azadirachta indica, Psidium guajava and Cymbopogon citratus were tested in Potato Dextrose Agar (PDA) medium to determine their percentage inhibitions against the organisms isolated from the tubers. The layout for experiment was a Completely Randomized Design (CRD) with seven (7) treatments and three (3) replications. Data was collected on some chemical constituents on both yam varieties of (D. rotundata and D. alata) and seven (7) leaf extracts used for the experiment. Result revealed that D. rotundata recorded higher chemical constituents than D. alata. The results of the study showed that Azadirachta indica extracted with ethanol as bio-pesticides for the experiment was the most fungitoxic as it possessed the best level (%) of inhibition on all the organisms isolated from yam varieties of D. rotundata and D. alata this could be because it contains phytochemicals such as Alkaloids, Flavonoids, Tannins, Phenols in reasonable percentage more than other plant extracts used in this work. It substantially suppressed the growth of A. niger. Furthermore, Azadirachta indica was most fungitoxic on rot diseases of A. niger (9.8%), Yeast (11.13%) and Rhizopus stolonifer (11.53%) isolated from D. alata and D. rotundata while Carica papaya (12.0%) was found to be most effective in the control of rot diseases of Fusarium oxysporium during the investigation. The application of Azadirachta indica was able to limit the growth of all the microorganisms identified during pathogenicity test. On point of attack the varieties of D. alata and D. rotundata showed that the most susceptible point of attack on the tubers was the basal part. The losses due to pathogenic attack was significantly reduced mostly by Azadirachta indica followed by Vernonia amygdalina then Carica papaya when Ocimum gratissimum was the lowest and are therefore recommended in that sequence.
Open Access
Finite deformation of internally pressured compressible synthetic rubber-like material
(Federal University of Technology, Owerri, 2021-07) Egbuhuzor, Udechukwu Peter
The finite deformation of internally pressurized isotropic compressible synthetic rubber material governed by Levinson and Burgess strain energy function is analysed. The analysis led to a secondorder nonlinear ordinary differential equation for the determination of stresses and displacements. Analytic solution is found impossible for now, hence, the solution is sought numerically using two methods namely shooting method and collocation method on mathematica(ode45 solver). The simulation of the system is made for ρ = 14N/m2 , and the cylindrical symmetric deformation attained its maximum displacements and stresses at r(1) = 1.16638m and σrr = (−1.2973e − 05)kg/m/s2 while at ρ = 0.5N/m2 , the spherical symmetric deformation obtained its maximum displacements and stresses at r(1) = 0.01853m and σrr = (−0.00035)kg/m/s2 respectively. The results of the two schemes were statistically compared using t-test and results obtained showed, the two methods have no significant difference. Similarly, for the cylindrical deformation, the t-test showed that the two methods have no significant difference which validates the solutions.
Open Access
Management systems for sustainble productivity of plantain ratoon crops intercropping systems in the tropical ultisol of Imo State, Nigeria
(Federal University of Technology, Owerri, 2021-07) Iwuanyanwu, Uzoma Prince
Two field experiments were conducted at Umuagwo, Imo State in 2013 and 2014 cropping seasons to investigate management systems for sustainable productivity of plantain ratoon crops intercropping systems in the tropical ultisol of Imo State, Nigeria. Experiment one was the evaluation of the effect of four organic manure sources on the growth and yield of plantain ratoon crops under different cassava densities and to evaluate weed suppressibility at varying population of plantain ratoon crops / cassava mixture. Experiment two was the evaluation of the residual effects of the organic manure sources and ash on the plantain ratoon/ cassava mixture. The organic manure sources were zero, poultry manure at 10 tons/ha, pig dung at 10 tons/ha and cow dung at 10 tons/ha. The ash was a blanket application each applied at 5 tons/ha as organic amendment. The cassava densities were 100.0 x 50.0 cm (20,000 plants/ha), 100 x 100.0 cm (10,0000 plants/ha) at 100.0 x 200.0 cm (5,000 plants/ha). Experiment one and two were all 3 x 4 factorial experiments arranged in randomized complete block design (RCBD) with 12 treatments replicated three times. Plant height (cm), number of functional leaves, stem girth (cm), leaf area (cm2), days to 50 % flowering (months), number of hands/bunch, number of suckers/plant, bunch weight (tons/ha), cassava plant height (cm), number of branches, plant canopy cover(m2), stem yield (bundles/100 stems), weed dry weight (kg/ha), cassava tuber weight (tons/ha) were the evaluated parameters. The result from experiment one showed that organic manure sources had significant effect on the growth and yield of plantain ratoon crops /cassava mixture. Poultry manure at 10 tons/ha performed significantly better in both growth and yield parameters and suppressed weeds when compared with pig dung at 10 tons/ha and cow dung at 10 tons/ha. Experiment two showed that poultry manure at 10 tons/ha + ash at 5 tons/ha performed significantly better in both growth and yield parameters and when compared with pig dung at 10 tons/ha + ash at 5 tons/ha and cow dung at 10 tons/ha + ash at 5 tons/ha. Cassava densities produced significant (P>0.05) increase in both growth and yield parameters assessed in the order of 100.0 x 100.0 cm (10,000 plants/ha) > 100.0 x 50.0 cm (20,000 plants/ha) > 100.0 x 200.0 cm (5,000 plants/ha). Poultry manure at 10 tons/ha, + ash at 5 tons/ha + 100.0 x 100.0 cm (10,000 plants/ha) cassava densities were more associated with bunch weight and tuber weight of cassava with 9.47 tons/ha for plantain and 10.52 tons/ha and 18.92 tons/ha and 19.98 tons/ha for cassava root yield both in 2013 and 2014 cropping seasons and in other yield components and may serve as a yardstick for selection of organic manure source, ash and densities. The physical and chemical analysis of the soil in both cropping seasons had that the nutrients persisted in the soil indicating that poultry manure, ash with 10,000 plants/ha cassava density had the best result in 2014 cropping seasons. For maximum production of plantain ratoon crops / cassava mixture, poultry manure at10 tons/ha + ash at 5 tons/ha with cassava density 100.0 x 100.0 cm (10,000 plants/ha) should be adopted.
Open Access
Design and modelling of smart home technologies for the aged persons
(Federal University of Technology, Owerri, 2021-07) Okoroafor, Godfrey Nwaji
Smart home technology for the aged persons here is a wireless sensor-based home system that provide the aged persons a safe, sound and secure home environment, while enabling them to live independently in their own homes as long as possible. The aged persons here are that population within the ages of 65 years and above. Nowadays, the rapid increase in the number of aged persons, including those with disabilities, the decrease in the number of family care-givers as a result of youths` migration to cities in search of white-collar jobs, and inability of government to provide adequate infrastructural needs to these aged persons has resulted in a miss-match on the caring facilities in Nigeria. These have contributed to the problem of these aged persons, since neither families nor government are able to meet their needs, especially in Africa due to high level of mass poverty, illiteracy and corruption in governance. Therefore, the task of this proposed system here is to design and model a voice activated home control system that will utilize the natural voice of the aged home occupants, to provide a more convenient, easier to install and use, user friendly home technologies for the aged persons. This will enable them maneuver assistive wheelchair, and manage home appliances through voice commands. This assistive wheelchair developed is embedded with collision detection and avoidance. The tools used to realize this proposed system are; The Personal Computer (PC), HC-SR04 ultrasonic sensor, and Voice Recognition (VR) module in a PC used for voice processing and recognition, Microphone for voice signal acquisition, C-language with the help of C# for coding. Bluetooth and Radio Frequency (RF) transceivers wirelessly link the input module to the controller module (microcontroller) which selects the appliances/assistive device to be controlled according to the input voice command. Proteus Virtual System Modelling (VSM) was used for developing smart home technology system schematic model and carried out the animated simulation to validate the system`s performance within the home. The designed system was tested on Dead Home (a home with closed curtains, carpet, an air-conditioner, and other leaving home appliances switched off) and Live Home (a home with opened curtains, carpet, an air-conditioner, television, and other leaving home appliances, switched on, and with background music or noise from a stereo people) conditions, and the effective result was 92.93% for dead home and 75.85% for live home respectively. This showed that the realized system controlled the devices with voice, though, the level of this system response is higher in dead home than in a live home, hence, the level of the system performance is lower in a noisy environment.
Open Access
Development of an improved model for big data analytics using dynamic multi-swarm optimization and unsupervised learning algorithms
(Federal University of Technology, Owerri, 2021-07) Oleji, Chukwuemeka Philips
An improved model for big data analytics was developed in this work using dynamic multi-swarm optimization and unsupervised machine learning algorithms. The problems of premature convergence of traditional data mining models due to the influence of heterogeneous data types and the voluminous nature of big data were solved with the developed Dynamic-K-reference Clustering Algorithm. Java programming language was used for implementation and Python Jupyter Notebook, Apache Spark frameworks were utilized for the virtualization of the clustered output results. The developed model was used to analyze a big dataset of Boko Haram insurgency attacks in Nigeria. The big dataset of Boko Haram terrorist attacks was scraped from the social media. The attributes of the dataset including the area of attacks, period of attacks, death tolls, and attack strategies were used for the analysis for the period of 2008 to May 2019. The output clustered results of the area of attack produced 64% at Borno, Abuja 1.3%, Adamawa 1.3%, Gombe 3.8%, Kano, 2.5%, Kastina 2.5%, Maiduguri 20% and Yobe 5% respectively. The output clustered results of death tolls at different years produced 4.1% on 2011, 15.6% on 2012, 3.4% on 2013, 6.0% on 2014, 42.6% on 2015, 0.0% on 2016, 2.8% on 2017, 6.0% on 2018 and 19.5% on 2019 respectively. The results show constant attacks of Boko Haram insurgency in the study area, which had led to millions of people currently displaced and killed. The Dynamic-K-reference clustering algorithm is resourceful enough to provide clustering accuracy of 0.9820 and clustering sum of square error of 0.0018 from the analysis of the Boko Haram attacks dataset. In other to validate Dynamic-K-references clustering algorithm its performance was compared with the existing algorithms on six datasets from the machine learning repository: Hepatitis, Australian Credit Approval, German Credit Data, Starlog Heart, Soybean and Yeast. The analysis of four datasets with Dynamic-K-references clustering algorithm when compared with PSO-based K-prototype algorithm produced performance improvement of 22%, 17%, 34%, and 12%, respectively. Similar analysis of Soybean and Yeast datasets with the existing MixK meansXFon algorithm and the Dynamic-K-reference clustering algorithm produced performance improvement of 13.8% and 13.7% respectively. From the analysis the Dynamic-K-reference algorithm was found to be robust and very efficient at expelling outliers from its dissimilar clusters/classifications. Future work should develop big data analytic services with the improved Dynamic-K-reference clustering algorithm and other improved models of its kind using a service oriented architectural methodology for real time analysis and prediction.
Open Access
Molecular characterization of methicillin resistant staphylococcus aureus from clinical specimens and antimicrobial activity of plant extracts against the isolates
(Federal University of Technology, Owerri, 2021-09) Ifediora, Afoma Chinwe
Staphylococcus aureus is a major bacterial pathogen that causes different community and hospital-acquired infections. S. aureus resistant to methicillin has become a big and expanding problem of concern in many developing countries. This study examined the molecular characterization and the effect of plant extracts on methicillin resistant Staphylococcus aureus (MRSA) from clinical specimens in Abia State, Nigeria using standard recommended procedures. Conventional cultural, morphological and biochemical methods were used to identify the isolates, while the antimicrobial susceptibility testing was performed by the disc diffusion method. Methicillin resistance was detected phenotypically using cefoxitin 30µg disc and oxacillin 1µg disc. Inducible clindamycin resistance was evaluated by the D-test. Polymerase chain reaction (PCR) was used to amplify genes for methicillin resistance (mecA), clindamycin resistance (ermB), beta-lactamase production (blaZ), Panton Valentine leukocidin (pvl) with 16SrRNA gene being the internal control. Sequencing was carried out on the amplified isolates. The Random Amplified Polymorphic DNA (RAPD) was implemented on the mecA strains isolated using three randomly selected oligonucleotide primers. Plant antimicrobial assay was done using the agar well technique and phytochemicals detected in the two plants tested. A total of 750 clinical specimens of blood, urine samples, wound, ear, nasal, high vaginal, urethral and ear swabs were collected from three major health facilities located in the three senatorial zones of Abia State, Nigeria. A total of 265 (35.3%) S. aureus isolates were recovered, out of which 126(47.5%) were from males and 139(52.5%) were from females, however there was no association between the prevalence and gender (p-value = 0.05) and also prevalence and age (p-value = 0.52). Phenotypic detection of MRSA using cefoxitin disc diffusion gave an MRSA prevalence of 164(61.9%) with 65(39.6%) being from urine, 3(23.1%) from wound, 31(18.9%) from high vaginal swab, 22(13.4%) from urethral swab, 4(2.4%) from ear swab, 3(1.8%) from nasal swab and 1(0.6%) from blood samples. All (100%) of the MRSA were susceptible to vancomycin, 120(73.2%) to clindamycin, 92 (56.1%) to gentamycin. All were resistant to ceftazidine, 157(95.7%) to cloxacillin, 146(89.0%) to augmentin, 136(82.9%) to ceftriaxone and 103(61.6%) to erythromycin. The MRSA strains showed much higher resistance rate than their methicillin susceptible Staphylococcus aureus (MSSA) counterparts to all tested antibiotic except clindamycin. Exactly 64(39.0%) of the MRSA were resistant to 4 classes of antibiotics indicating multi drug resistance (MDR). The overall prevalence of inducible clindamycin resistance among methicillin resistant isolates was 29(17.7%) while 66.5% xix produced beta-lactamase. Out of 40 cefoxitin positive isolates, 12 (30%) possessed mecA gene, 17.5% harboured the β-lactamase (blaZ) gene, 20% and 10% possessed the pvl gene. Dendogram analysis of RAPD-PCR amplification of mecA positive strains showed three different clones in circulation in the state. The plant extracts showed varied levels of antimicrobial activity against the MRSA isolates. The growth of the microorganisms used for the test was inhibited by the ethanolic extracts of the leaves of Alchornea cordifolia and Acalypha wilkesiana at concentrations of 50mg/ml to 200mg/ml. The inhibition zones ranged from 9.0mm to 21.0mm whereas the water extracts showed moderate activity against the isolates. The Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of Alchornea cordifolia ranged from 12.5-50mg/ml and 25-100mg/ml for Acalypha wilkesiana. The results of the rates of kill revealed a gradual reduction in the total viable count of bacteria from 1hr to 24hrs in all the test isolates. The phytochemical screening of the ethanol extract revealed the presence of tannins, flavonoids, glycosides, resins and carbohydrates but in variable degrees. The percentage yields of phytochemical content of the leaves of the Alchornea cordifolia plants were as follows: alkaloids (1.85%), flavonoids (1.08%), Glycosides (1.05%), saponins (4.13%), and tannins (0.70%). The use of phenotypic and molecular methods in this study provided useful information on antibiotic resistance and genetic diversity of S. aureus isolates from clinical specimens in Abia State of Nigeria. The information provided could help in monitoring the evolution of S. aureus strains in Nigeria over time.
Open Access
Prospectivity study of mineral and geothermal energy resources in parts of SouthEastern Nigerian Sedimentary Basin
(Federal University of Technology, Owerri, 2021-09) Okiyi, Ijeoma Millicent
There has been an open search for clean/renewable energy and mineral resources for economic growth using airborne geophysical surveys. High resolution airborne magnetic and radiometric data, five scenes of Landsat 8 remote sensing, SP and VES Schlumberger data of parts of Southeastern Nigerian sedimentary basin were analysed and interpreted with a view to delineate regimented mineral colonies and anomalous zones of geothermal gradient. Reduction to Equator and Vertical Derivative filters were applied to the airborne magnetic data to centre anomaly peaks over causative bodies, define shapes and edges of magnetic sources and map magnetic lineaments. Fast Line-in-sight Atmospheric Analysis for Spectral Hypercube (FLAASH) and subsequent post FLAASH band maths were applied to the remote sensing data to generate the surface reflectance data from which ratio composite and lineament maps were generated. Results showed dominant NE-SW and E-W lineament trends from Landsat and Magnetic data with subordinate NW-SE trend. 50% overlapping data windows selected for spectral analysis were used to delineate anomalous geothermal gradients. The vertical, horizontal and NTilt derivative maps were used to reveal boundaries of mafic intrusives and inclusions which are most likely controlled by the trends of deep-seated magnetic lineaments. The derivative maps were also used to enhance edges of shallow structures. Alteration zones, lithologic/geologic boundaries were revealed by radioelement ratio, ternary and total count maps and Landsat ratio map composites 4/2, 6/5 and 6/7 and PCA plots. The Source Parameter Imaging, 3D Euler Deconvolution and Magnetic Vector Inversion modelling depth estimate filters established depths to, and geometry of, subsurface magnetic structures. Results revealed shallow to deep-seated structures in the depth range of 80 m asl to >7 km bsl which must have aided development of veins and hosted lodes of intrusives and ore bodies. Shallow Curie Point Depth (< 10km), geothermal gradient > 42°C/km and heat flow > 88mW/m2 from spectral analysis procedure have been earmarked for good geothermal reservoirs. VES geoelectric sections and 2D imaging results beneath two zones of anomalous geothermal gradient between 35 to 45 (°C/km), proposed approximate models of geothermal resources as Hot Dry Rock (HDR) for Alok and geo-pressured model for Amagunze. Cylindrical/lenticular sills, inclined dykes, sparse nodules and spheres were identified from probed windows of the RTE-TMI map as surface to deep-seated models. Ground-truthing these findings, field image and double dipole results indicated mineralization of the study area as true, hence, making it a viable mineral and geothermal prospect environment.
Open Access
Studies on antibacterial, antifungal and antioxidant activities of curcum longa, mimosa pudica, euphorbia serrata medicinally used in Nigeria
(Federal University of Technology, Owerri, 2021-09) Ugenyi, Assumpta Ugbonma
Three plants –Euphorbia serrata, Mimosa pudica L. and Curcum longa L. suggested from their ethno-medicinal uses to possess antimicrobial, and antioxidant activities were evaluated for their different biological activities. Phytochemical analyses were carried out using standard qualitative and quantative analytical methods. Antimicrobial activities were determined by well diffusion method for the isolates; Proteus mirabilis, Alcaligenes faecalis, Klebsiella pneumoniae, Wohlfahrtiimonas chitiniclastica, Candida tropicalis and Wickerharmoyces anomalus identified using DNA sequencing. The antioxidant potentials of the extracts were determined by their abilities to scavenge 2, 2-diphenyl-1- picrylhydrazyl radical, nitric oxide radical, hydrogen peroxide.The antioxidant potentials were further determined by the reducing power using standard methods. Acute and sub-chronic oral toxicity of the extracts were carried out with Lorke′s method using male albino rats. Pathology examinations of the organs (liver, kidney and heart) were also evaluated. Results of phytochemical analysis revealed the presence of Alkaloids (E. serrata 6.85%; M. pudica2.94%; C. longa 5.28%), Tannins (E. serrata, 35.2%; M. pudica, 24%; C. longa 24.2%), Saponnins (E. serrata 5.77%; M. pudica 6.20%%; C. longa 7.26%), Flavonoids (E. serrata 9.80%, M. pudica 53.8%, C. longa 13.18%), %) and Cardiac glycosides (E.serrata 5.31%, M. pudica 3.22%, C. longa 3.30%). All the extracts inhibited the growth of both bacteria(effective zone of inhibition 7 to 26 mm) and fungi (effective zone 5 to 17 mm) compared to chloramphenicol and griseofulvin respectively. Aqueous extracts of C.longa. had no inhibition for A. faecalis and the fungi at 25mg/ml. The magnitude of bacterial inhibition by the extracts followed order (M.pudica > C.longa > E.serrata) and (C.longa > E. serrata > M.pudica) for the fungi. Scavenging of DPPH, nitric oxide, H2O2 radicals and reducing power ability were concentration dependent. Ethanolic extracts had a significant (p < 0.05) antioxidant scavenging activities for H2O2 and reducing power. E. serrate, M. pudica, C. longa exhibited a strong reducing power (R.P 0.5AU = 15.01 µg/ml, 10.0 µg/ml, 9.38 µg/ml) (R.P 0.5AU = 34.09 µg/ml, 21.77 µg/ml and 21.63 µg/ml) for ethanol and methanol extracts respectively and effectively scavenged DPPH, nitric oxide and H2O2 radicals. Threshold inhibitory concentrations (IC50) of E. serrate, M. pudica, C. longa and ascorbic acid against DPPH radicals were (28.74 µg/ml,19.64 µg/ml,15.62 µg/ml and 15.62 µg/ml ) for ethanol extracts and (2.92 µg/ml, 16.10 µg/ml, 12.50 µg/ml and 15.62 µg/ml) for methanol extracts. IC50 of E. serrate, M. pudica, C. longa and ascorbic acid for nitric oxide radicals were (22.67µg/ml, 50.02µg/ml, 48.34µg/ml and 15.46 µg/ml) for ethanol extracts and (16.55µg/ml, 16.17 µg/ml, 15.36 µg/ml and 15.46 µg/ml) for methanol extracts. IC50 of E. serrata, M. pudica, C. longa and ascorbic acid against H2O2 radicals were (15.31 µg/ml, 15.26 µg/ml, 15.26 µg/ml and15.15 µg/ml) for ethanol extracts and (15.48 µg/ml, 24.17 µg/ml, 35.03 µg/ml and 15.15 µg/ml) for methanol extracts. Mortality from the extracts at a single dose of 5000 mg/kg body weight, were revealed. Sub-chronic oral toxicity of the extracts 200 mg/kg and 400 mg/kg body weight revealed non-significant difference (p ˃ 0.05) on the biochemical parameters (ALT, AST, ALP, LDH, SOD, GSH, TP, GPx, CAT, ALB, Urea and Creatinine). Haematology parameters (HB, WBC, RBC, PVC) values when compared with control, showed significant difference (p ˂ 0.05).Similar results were also revealed for body weight when compared with control. Examination of the liver, kidney and heart showed no significant morphological changes except with M. pudica, where observed pathological changes include fatty degeneration and inflammatory cells (lymphoctyes and macrophages) irrespective of extract dosage.
Open Access
Molecular characterization of mycotoxin producing moulds from grains and legumes and their susceptibility to plant extracts
(Federal University of Technology, Owerri., 2021-11) Ohabughiro, Ndidi Blessing
Molecular characterization of mycotoxin producing moulds from grains and legumes and their susceptibility to plant extracts was studied. Grains and legumes were stored for a period of two and four months. They were analysed for the presence of moulds and mycotoxin producing moulds. They were also analysed for the production of different mycotoxins. Sabouraud dextrose agar, Sabouraud dextrose broth, potato dextrose agar and malt extract agar were used in this study. The methods of isolation used were direct physical examination and direct plate count method. Moulds were identified based on their colony morphology, cultural characteristics and molecular characterization. Mycotoxin analysis was done using Liquid chromatography tandem mass spectrometry. Antifungal susceptibility test was done using the Clinical Laboratory and Standards Institute approved methods for testing of moulds using disk diffusion method. The following four oxoid antifungal agents were used: Amphotericin B, fluconazole, ketoconazole and voriconazole. The following medicinal plants: Ocimum gratissimum (scent leaves), Vemonia amygdalina (bitter leaves), Gongronema latifolium (utazi leaves) and Piper guineense (uziza leaves) were assessed for their phytochemical properties and antifungal susceptibility profile against various moulds. The organic solvents used for antifungal susceptibility profile were methanol and hot water. One way analysis of variance, Duncan tests and descriptive statistics were used for statistical analysis. The moulds isolated and identified culturally were Aspergillus sp. Aspergillus flavus, Aspergillus niger, Aspergillus ochraceus, Penicillium chrysogenum, Fusarium sp, Rhizopus stolonifer, Rhizopus nigricans and Mucor sp. while those identified molecularly were Aspergillus flavus, Aspergillus tamarii, Aspergillus niger, Aspergillus brunneoviolaceus, and Penicillium chrysogenum. The genus Aspergillus was the most prevalent mould. Groundnut had the highest number of isolates followed by maize, beans, rice while wheat had the least number of isolates. The numbers of colony forming units were more in Potato dextrose agar, Sabouraud dextrose agar and least on malt extract agar. Potato dextrose agar recovered the highest number of isolates from both unstored and stored samples followed by sabouraud dextrose agar then malt extract agar. The following mycotoxins were detected Aflatoxin B1, Aflatoxin B2, Aflatoxin G1, Aflatoxin G2, Ochratoxin A, Citrinin, Dihydrocitrinone, Fumonisin B1, Fumonisin B2, Fumonisin B3, Fumonisin B4, Zearalenone, Deoxynivalenol and Nivalenol. Aflatoxin was the most frequent mycotoxin detected. Rice (1286.3 ± 29.689 µg/kg) had the highest rate of recovery of mycotoxins followed by wheat (1166.8 ± 0.901 µg/kg) and groundnuts (1142.9 ± 10.488 µg/kg) while maize (1111.6 ± 9.810 µg/kg) had the least concentration of mycotoxins. Ketoconazole (39 ±1.000 mm) had the highest minimum inhibitory concentration among different anti-fungal agents, followed by voriconazole (36 ± 2.000 mm), Amphotericin B (30 ±2.000 mm) and then Fluconazole (21 ± 12.124 mm). Susceptibility profile using only tetrazolium gave no zone of inhibition. Antifungal agents alone gave a better zone of inhibition than the combination of antifungal agents with tetrazolium. The medicinal plants such as scent leaves, bitter leaves, uziza leaves and utazi leaves analysed contained the following phytochemicals tannin, alkaloid, steroid, saponin and flavonoid. Percentage growth inhibition of moulds by methanol and hot water xiiiextract of scent leaf gave the highest inhibition followed by bitter leaf, utazi and uziza gave the least growth inhibition. Methanol extract gave a better inhibition than hot water extract at 100 mg/ml and 50 mg/ml. One-way analysis of variance and Duncan tests showed that there was a significant difference (P < 0.05) between the isolates found in stored and unstored grains and legume. There was also a significant difference (P < 0.05) between the antifungal agents and media used. Potato dextrose agar should be used frequently since it gave the highest rate of mould recovery. Ketoconazole remains the best drug of choice among other antifungal agents against moulds. Medicinal plants like scent leaves, bitter leaves, utazi leaves and uziza leaves gave varying levels of growth inhibition against various isolates and should be used both at home and clinical settings. The grains and legumes studied were contaminated with various species of moulds and contained many mycotoxins of public health importance.
Open Access
Molecular characterization of mycotoxin producing moulds from grains and legumes and their susceptibility to plant extracts
(Federal University of Technology, Owerri, 2021-11) Ohabughiro, Ndidi Blessing
Molecular characterization of mycotoxin producing moulds from grains and legumes and their susceptibility to plant extracts was studied. Grains and legumes were stored for a period of two and four months. They were analysed for the presence of moulds and mycotoxin producing moulds. They were also analysed for the production of different mycotoxins. Sabouraud dextrose agar, Sabouraud dextrose broth, potato dextrose agar and malt extract agar were used in this study. The methods of isolation used were direct physical examination and direct plate count method. Moulds were identified based on their colony morphology, cultural characteristics and molecular characterization. Mycotoxin analysis was done using Liquid chromatography tandem mass spectrometry. Antifungal susceptibility test was done using the Clinical Laboratory and Standards Institute approved methods for testing of moulds using disk diffusion method. The following four oxoid antifungal agents were used: Amphotericin B, fluconazole, ketoconazole and voriconazole. The following medicinal plants: Ocimum gratissimum (scent leaves), Vemonia amygdalina (bitter leaves), Gongronema latifolium (utazi leaves) and Piper guineense (uziza leaves) were assessed for their phytochemical properties and antifungal susceptibility profile against various moulds. The organic solvents used for antifungal susceptibility profile were methanol and hot water. One way analysis of variance, Duncan tests and descriptive statistics were used for statistical analysis. The moulds isolated and identified culturally were Aspergillus sp. Aspergillus flavus, Aspergillus niger, Aspergillus ochraceus, Penicillium chrysogenum, Fusarium sp, Rhizopus stolonifer, Rhizopus nigricans and Mucor sp. while those identified molecularly were Aspergillus flavus, Aspergillus tamarii, Aspergillus niger, Aspergillus brunneoviolaceus, and Penicillium chrysogenum. The genus Aspergillus was the most prevalent mould. Groundnut had the highest number of isolates followed by maize, beans, rice while wheat had the least number of isolates. The numbers of colony forming units were more in Potato dextrose agar, Sabouraud dextrose agar and least on malt extract agar. Potato dextrose agar recovered the highest number of isolates from both unstored and stored samples followed by sabouraud dextrose agar then malt extract agar. The following mycotoxins were detected Aflatoxin B1, Aflatoxin B2, Aflatoxin G1, Aflatoxin G2, Ochratoxin A, Citrinin, Dihydrocitrinone, Fumonisin B1, Fumonisin B2, Fumonisin B3, Fumonisin B4, Zearalenone, Deoxynivalenol and Nivalenol. Aflatoxin was the most frequent mycotoxin detected. Rice (1286.3 ± 29.689 µg/kg) had the highest rate of recovery of mycotoxins followed by wheat (1166.8 ± 0.901 µg/kg) and groundnuts (1142.9 ± 10.488 µg/kg) while maize (1111.6 ± 9.810 µg/kg) had the least concentration of mycotoxins. Ketoconazole (39 ±1.000 mm) had the highest minimum inhibitory concentration among different anti-fungal agents, followed by voriconazole (36 ± 2.000 mm), Amphotericin B (30 ±2.000 mm) and then Fluconazole (21 ± 12.124 mm). Susceptibility profile using only tetrazolium gave no zone of inhibition. Antifungal agents alone gave a better zone of inhibition than the combination of antifungal agents with tetrazolium. The medicinal plants such as scent leaves, bitter leaves, uziza leaves and utazi leaves analysed contained the following phytochemicals tannin, alkaloid, steroid, saponin and flavonoid. Percentage growth inhibition of moulds by methanol and hot water xiii extract of scent leaf gave the highest inhibition followed by bitter leaf, utazi and uziza gave the least growth inhibition. Methanol extract gave a better inhibition than hot water extract at 100 mg/ml and 50 mg/ml. One-way analysis of variance and Duncan tests showed that there was a significant difference (P < 0.05) between the isolates found in stored and unstored grains and legume. There was also a significant difference (P < 0.05) between the antifungal agents and media used. Potato dextrose agar should be used frequently since it gave the highest rate of mould recovery. Ketoconazole remains the best drug of choice among other antifungal agents against moulds. Medicinal plants like scent leaves, bitter leaves, utazi leaves and uziza leaves gave varying levels of growth inhibition against various isolates and should be used both at home and clinical settings. The grains and legumes studied were contaminated with various species of moulds and contained many mycotoxins of public health importance.