http://hdl.handle.net/123456789/109 2026-04-04T12:02:26Z http://hdl.handle.net/123456789/2127 A PALYNOSTRATIGRAPHIC STUDY OF THE ENVIRONMENTS AND THERMAL MATURATION OF ONSHORE OREDO FIELD, NIGER DELTA OYELAMI, Ayobami Babalola The Niger Delta is a mature basin in Nigeria with petroleum reserve of about 40 billion barrels. The onshore Niger Delta Paleogene-Neogene, where exploration commenced and was concentrated before activities shifted to the offshore and deep-offshore Neogene-Quaternary, has not been fully explored. The shift of exploration focus led to a neglect of work on onshore Paleogene palynostratigraphy. This study was aimed at investigating the palynostratigraphy, paleoclimate and hydrocarbon potential of the periods. Five hundred and eighty-five ditch cutting samples in Oredo Field, OML 111: Oredo-2 (244); Oredo-4 (195); and Oredo-8 (146) were provided by the Nigeria Petroleum Development Company, Benin. Sub-samples (25 grams each) were subjected to conventional palynological maceration procedures for the retrieval and concentration of palynomorphs and palynomacerals, while standard laboratory procedures were applied for micropaleontological sample preparation and lithologic descriptions. Retrieved palynomorphs and palynomacerals were mounted on microscope slides and observed using a high-power research photomicrographic microscope. The microfauna and lithology were studied using a stereomicroscope. Characteristic palynological assemblages associated with the recognised systems tracts within the sequence stratigraphic framework were defined. Biostratigraphic data were processed using conventional biostratigraphic software with stratigraphic ages cross plotted against depth generated in chronostratigraphic charts. Data were analysed using descriptive statistics. The palynomorph assemblages contained abundant and diverse palynomorphs with pollen, fungal spores, dinoflagellate cysts and pteridophyte spores constituting, respectively, 63.0%, 18.8%, 8.1% and 7.4% of the totality of assemblages in the three wells. Twelve new palynological zones were established from the stratigraphic distribution of marker species based on their appearance and extinction datums and local assemblage ranges. Four palynocycles (1, 2, 3 and 4) of alternating wet and dry climatic regimes were identified based on ecological indicator plant species. The percentage distribution of the palynomacerals revealed the dominance of amorphous organic matter with phytoclasts and palynomorphs, which aided the subdivision of the wells into three palynofacies associations: PF-I, PF-II and PF-III. Two distinct organic facies represented by orange to orange-brown (TAI 3) and yellow to orange (TAI 2) indicating early mature and immature hydrocarbon potentials, respectively, were recognised. Recovery of microforaminifera, consisting of 87.0% benthics and 13.0% planktics was generally low. Two lithostratigraphic units, Agbada and Benin Formations, were delineated. Integration of palynostratigraphic and foraminiferal data suggested a Middle Eocene (Paleogene) to Early Miocene (Neogene) age for the analysed intervals. A combination of the palynofacies associations with other biostratigraphic data indicated palaeoenvironments shoaling from marine to terrestrial/continental. Two systems tracts – Transgressive Systems Tract (TST) and highstand systems tract – were recognised. Marine lithofacies with their associated TST in the Eocene are mature and lie within the oil and gas “windows”. Mapping of 41.0, 39.4, and 38.0 Ma maximum flooding surfaces with associated 40.1 and 38.7 Ma sequence boundaries were revealed. A new and more detailed palynostratigraphic zonation comprising twelve zones for the Niger Delta Paleogene/Neogene was established. Four palynocycles of alternating wet and dry climatic cycles were revealed. The Eocene shale within the Agbada Formation were matured regarding hydrocarbon potentials. 2023-09-01T00:00:00Z http://hdl.handle.net/123456789/1602 CREAM FORMULATION FROMDACRYODES EDULIS (G. DON) H. J. LAM AND ANACARDIUM OCCIDENTALE LINN. AGAINST SELECTED PATHOGENIC ORGANISMS ASSOCIATED WITH CERTAIN SKININFECTIONS APONJOLOSUN, BABALOLA SUNDAY Treatment of skin infections is of global concern due to contraindications, microbial resistance to conventional creams and their associated high cost. Saps from leaves of Dacryodes edulis (De) and Anacardium occidentale (Ao) are traditionally used topically for treating skin diseases. However, the effectiveness of these leaves in skin cream formulation has not been reported. Therefore, this study was designed to investigate the effectiveness of De and Ao leaves, and creams formulated against selected skin diseases causative agents. Methanol extracts of De and Ao leaves were partitioned separately with n-hexane, ethyl acetate, butanol and water. Phytochemical analyses were conducted using standard procedures. Antioxidant analyses using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and Ferrous Ion-Chelating (FIC) were carried out. Antimicrobial tests on twelve microorganisms were conducted using standard procedures. Six oil-in-water creams, FDe1, FDe2, FDe3 and FAo1, FAo2, FAo3, were produced from ethyl acetate fractions of De and Ao, respectively using standard pharmaceutical procedures. Creams formulated were evaluated for physicochemical properties, while antimicrobial assay of the creams was conducted on selected clinical strains of bacteria and fungi. Intradermally, Staphylococcus aureus (0.5 mL of 10-8 CFU) was injected into 40 mice (5 per group), treated with 200 mg of the creams and Tydineal cream (as reference drug) for three days and the excised side skins were subjected to microbial count. Stored creams at 0oC, 29±4oC and 46oC were evaluated for stability using viscosity and organoleptic observation for 120 days. Creams’ sub-acute toxicity test was purposively done on 30 mice (5 per group) using standard procedures. Data were analysed using descriptive statistics and ANOVA at α0.05. Saponins (mg/100g) and carotenoids (μg/100g) in Ao and De were 1750.00±7.64, 925.00±7.64, (controls: 438.33±6.01, 711.67±4.41) and 1628.33±18.78, 1083.33±7.26, (controls: 231.67±7.26, 720.00±2.89), respectively. Scavenged free radicals of De for DPPH and FIC (86.29-34.89%, 40.24-13.13%) were significantly higher than Ao (42.46-2.27%, 21.67-0.00%), respectively. The ethyl acetate fractions were the most active antimicrobially. The colours, pH and globule sizes of De and Ao creams were light green to dark green and dark yellow to deep brown, 3.24-4.52 and 3.58-4.01, 29.12-95.99 and 55.38-188.4 μm, respectively. The FDe3 significantly inhibited Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, Trichophyton rubrum and Epidermophyton sp. (21.00±1.00, 16.00±2.00, 16.00±2.00, 11.70±0.60, 11.00±1.00 mm, respectively) than FAo3 (10.70±1.20, 8.00±0.00, 10.00±0.00, 4.00±0.00, 0.00±0.00 mm, respectively) and other formulated creams. Tydineal cream had highest inhibition on Staphylococcus aureus (87.93%) followed by FDe3 (85.89%), FAo2 (85.39%), FAo3 (85.32%), FAo1 (85.23%), FDe2 (85.21%) and FDe1 (85.03%), while the aqueous cream base was inactive. Viscosities of De and Ao creams were 3134-5060 and 2510-5495 cP, respectively with no significant difference among storage temperatures. Organoleptic properties of the creams at 0oC and 29±4oC remain unchanged, but colours were darkened in the creams at 46oC. Mice skins showed no lesions. The formulated creams with the highest quantity of the ethyl acetate fractions (FDe3 and FAo3) were effective against the tested microorganisms with no observed skin side effects. Dacryodes edulis cream was more effective than Anacardium occidentale cream. 2020-12-01T00:00:00Z http://hdl.handle.net/123456789/1289 AUTECOLOGY AND CONTROL OF Tithonia diversifolia (Hemsl.) A. Gray IN SOME SELECTED STATES OF NIGERIA OBIAKARA, Maxwell Chibiko Since its introduction in Nigeria in the 1970s, Tithonia diversifolia (Td),an invasive species has posed increasing threats to crop production and native species diversity. However, the autecology of Td which plays a key role in providing information for its control is yet to be fully understood. This study thereforeinvestigated some autecological and reproductive traits of Td in Nigeria. Principal Component Analysis-env was used tocompare the ecological niche of Td between its native range (Mexico) and its introduced range (Nigeria). The current and future geographical distributions of Td were modelled using Maximum Entropy principles. Impacts of Td were assessed on seed bank species diversity and soil physico-chemical properties using space-for-time substitution approach. Two Lowland Forests (LF), two Derived Savannas (DS) and one Jos Plateau Forest-grassland Mosaic sites were investigated. Nitrogen, Phosphorus and Potassium concentrations in soil and plant parts were determined using standard procedures in soil with highest Td. Mode of pollination, fecundity, germination and dormancy were assessed while seed bank behaviour and biomass were modelled in DS. Control of Td using paraquat dichloride, manual weeding and controlled agricultural burning were investigated using standard procedures. Data were analysed using descriptive statistics and Analysis of Variance (ANOVA) at α0.05. Tithonia diversifolia occupies a different niche in Nigeria compared to Mexico (Schoener’s D=0.01, E=0.99). Maximum entropy models revealed that DS is most suitable for Td establishment. Tithonia diversifolia exerted no significant impact on seed bank diversity of invaded habitats. However, it significantly altered soil pH, cation exchange capacity, total N, inorganic PO4, organic C, available P, Fe, Zn and Cu. The leaves had significantly high levels of N, P and K compared to other plant parts. Reproductive allocation of nutrients in DS revealed that N ranged from 5.88-17.40%, P, 8.60-31.65% and K,7.73-22.53%. Tithonia diversifolia is facultatively xenogamous with 93% fruit set in open-pollinated capitula and a high pollen-ovule ratio (4,167±76). It produced 49±3 capitula/plant, corresponding to 454-8124 achenes/plant. Achenes of Td were permeable but showed morphological dormancy with low germinability (8.67%). Mechanical scarification and Gibberellic acid increased germinability by 40 and 65%, respectively. Tithonia diversifoliaformed a transient seed bank (<6 months) with 2811±201 achenes/m2. Seed bank density was best fit with exponential decay model (density=1712e^(-0.49time)+24), with an initial density of 1736 achenes/m2 at the rate of 0.49 achenes/week. Biomass of Td one month after emergence was 2.36±0.38 g/m2. This increased by 91% after two months. Biomass of Td followed a logistic model,biomass= 179.7⁄((1+855.4e^(-2.25time) ) ). Mature Td biomass was 179.56±22.54 g/m2, with the largest proportion (67%) allocated to shoots. Paraquat dichloride application was most efficient in controlling Td with over 80% seedling mortality and 50% reduction in plant height. The prolific seed production and rapid vegetative growth of Tithonia diversifolia are responsible for its aggressive invasiveness. This species can be controlled using agricultural burning and systemic herbicide. 2021-07-01T00:00:00Z http://hdl.handle.net/123456789/1287 EVALUATION OF FUNGI ASSOCIATED WITH GROUNDNUT CAKE (KULIKULI) SAMPLES FROM SELECTED NORTHERN NIGERIAN STATES AND THEIR CONTROL WITH SOME BOTANICALS ABDUL-LATEEF, NANAMAYMUNA BOLA Groundnut cake (Kulikuli) is a common snack in Nigeria prepared from groundnut (Arachis hypogaea L.). Food contamination by aflatoxin-producing fungi remains a major health challenge in Nigeria. Fungal contamination in Kulikuli occurs during production, handling, storage and transportation. However, research on Kulikuli has focused on microbial characterisation and nutritional value. There is dearth of information on fungal infestation, mycotoxin production in Kulikuli and their control with botanicals having anti-fungal properties. Therefore, this study was aimed at evaluating fungi associated with Kulikuli production, aflatoxin secretion and their control using selected botanicals. Twenty five Kulikuli samples each were purchased from selected markets with Kulikuliproduction centres in Kano (Rimin Gado, Janguza, Kurmi, Sabongari, Rimi); Kaduna (Bacci, Kaduna Central, Kawo, Sabuwar Gari, Kakuri); Sokoto (Kanawa, Ilaela, Dange Shuni, Jabo, Yan tumatir); Zamfara (Bungudu, Tsohuwar Kasuwa, Dampa Sabuwar Kasuwa, Tudun Wada) and Abuja (Utako, Wuse, Madalla, Dutse, Bwari). Fungi associated with the Kulikuli samples were isolated and identified using morphological and molecular characterisations. Kulikuli with botanicals (MLB) and without botanicals (ML) were also prepared at the Mycology Laboratory Department of Botany as controls. The botanicals used were garlic, ginger and turmeric.Proximate analysis and aflatoxins (AFB1, AFB2, AFG1 and AFG2) contents of the samples were determined using standard procedures. Ten Simple Sequence Repeat primers were used for aflatoxin genes (AT, AN, AP, AFUM and FUS) in each isolated fungus. Data obtained were subjected to descriptive statistics and Analysis of Variance (ANOVA) at α0.05. One hundred and six fungi were isolated and identified as Aspergillusflavus (n=28), A. parasiticus (n=26), A. niger (n=7), A. tamarii (n=9), A. fumigatus (n=3), Penicillium oxalicum (n=11), P. chrysogenum (n=6), Fusarium oxysporum (n=10)and F.compaticum (n=6). All fungi isolated from market samples, except A. fumigatus and P. oxalicum were also isolated from Kulikuli samples prepared in ML without botanicals. Kulikuli samples with botanicals had no fungal incidence. Kulikuli samples from the markets compared with MLB and ML samples were significantly different in moisture content (11.91, 6.64, and 12.64%), ash (3.91, 4.84, and 4.84%), crude protein (49.23, 59.23, and 50.25%), fibre (3.20, 4.55, and 4.05%), fat (4.83, 3.26, and 3.83%) and pH (6.30, 6.88, and 6.84), respectively. Market samples had the highest AFB1, AFB2, AFG1 and AFG2 of 1.64, 2.10, 0.10 and 0.13 µg/kg, respectively, while samples treated with garlic had the least AFB1 (0.34µg/kg), AFB2 (0.37µg/kg), AFG1 (0.01µg/kg) and AFG2 (0.02µg/kg). Aflatoxin concentrations in MLB and ML samples were within tolerance limits of NAFDAC and European Union 4 µg/kg. The aflR, nor, ver and omt biosynthetic pathway genes found in aflatoxin producing fungi were detected in all fungi isolated from the purchased Kulikuli except strains from Kaduna (Kaduna Central) samples. However, the MLB samples yielded no fungal growth. Kulikuli samples from the studied areas were infested with nine fungi species. Aspergillus spp were the dominant fungi found to be most prevalent in the market samples. The addition of garlic during production of Kulikulibest suppressed fungal infestation and reduced aflatoxin levels. 2021-08-01T00:00:00Z