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Key physical characteristics of three dispersants: Corexit 9527, NalcoD4106 and Goldcrew were studied to determine their integrity and toxicity to a brackishwater fish Sarotherodon melanotheron. The results showed that with regards to the physical properties, Corexit 9527 and to a large extent Goldcrew maintained their integrity while NalcoD4106 deteriorated. Observations of the 96h LC50 static bioassay showed that the toxicity of the dispersants to the fish in an increasing order is Corexit 9527 < Goldcrew < NalcoD4106.

The in vitro effect of 10, 30 and 50% (w/v) concentrations of the aqueous and ethanolic extracts of pawpaw (Carica papaya L.) leaf on the radial growth of Fusarium verticilliodes was studied using the pour plate method. The diameters of radial growth of the mycelia of F. verticilliodes were measured at 24 hours intervals for five days. Both extracts retarded the radial growth of F. verticilliodes compared to that of the control, with the ethanolic extract having a greater fungistatic effect at the concentrations tested in this study.

: The copepoda (crustacea) of Lagos harbour system was studied from October 2002 to September 2003. Eighteen copepod species were identified, three of which are being recorded in Nigeria for the first time. Thesze are: Temora, Corycaeus and macrostella species. The copepods comprise of three assemblages, namely: the brackish/marine assemblage, the brackish assemblage and the brackish/freshwater assemblage. Salinity values varied from 33.40% at Lagos harbour to 0.40% at Badagry.

Plankton sampling and investigation of the Lagos harbour, some adjourning creeks and rivers was carried out using plankton, nets of 55µm and 100µm mesh sizes. Yewa river which is located between Lat. 6°25’ – 6°30’N and Long. 2°50’ – 2°55’E was one of the sampling, stations with salinity values ranging from 0.17 – 0.43% for the 8 months of sampling period, indicating a constant freshwater condition. In the course of analysis and identification of the copepoda, Salmincola species which is an ectoparasite of fish was found, and this is its first record from Nigeria water body

Phytochemical properties of the extracts of ginger (Zingiber officinale) and bulb of garlic (Allium sativum) indicate the presence of saponins, tannins, alkaloids, flavonoid and phytic acids. Extracts of Z. officinale and A. sativum were more effective in the treatment of oral pathogens when compared to antifungi (Ketoconanzone) and antibacterial (ciprofloxacin) drugs used as positive controls. Z.

The growth of seeds and tubers is a major concern due to increased salt stress and widespread accumulation of heavy metals in agricultural land. Amylase is an important enzyme involved in germination processes and seedling development. This study was carried out to determine the effects of salt stress and heavy metals on the activity of amylase in in vitro germinated Cyperus esculentus. Sodium chloride (NaCl), at concentrations of 0, 50, 100, 150, 200, 250 and 300 mM, were used to evaluate the effect of salt stress.

The aim of this research was to assess the efficacy of different extracting solvents on the phytochemical, antibacterial and synergistic effects of Bryophyllum pinnatum and Citrus aurantifolia. Four bacterial species: Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, and Pseudomonas aeruginosa were used as test organisms and the antibacterial activity of the extracts was determined by the agar-well diffusion method.

Phylogenetic and functional gene analysis of sulphate-reducing bacteria (SRB) from crude oil and produced water was carried out using molecular methods. The concentration of hydrogen sulphide (H2S) produced by SRB, as an indication of SRB presence, was determined using spectrophotometric sulphide assay. More H2S was observed to be produced at 55 ˚C than at 30 ˚C, with sample B found to produce more H2S at these temperatures than sample A. This implies more SRB contamination in sample B, possibly from subterranean water.

The antimicrobial screening, functional groups and elemental analysis of Aframomum melegueta seeds were investigated using standard microbiological methods. The results revealed that the extracts of Aframomum melegueta had inhibitory effect against selected oral microorganisms such as Staphylococcus epidermidis, Escherichia coli, Streptococcus mutans, Klebsiella pneumoniae, Aspergillus niger, Candida albicans, Rhizopus oryzae, Aspergillus flavus.

The use of plant growth regulators in tissue culture media is critical for callogenesis. The type and concentration of auxin and cytokinin used have profound effect on callus induction. In this study, three types of auxin and one cytokinin were investigated for media supplementation. The auxins were naphthalene acetic acid (NAA), indole acetic acid (IAA) and 2,4-dichlorophenoxyl acetic acid (2,4-D), each at concentrations of 0, 2.5, 5.0, 7.5 and 10 mg/l. The cytokinin used was benzyl amino purine (BAP) at concentrations of 0, 0.1, 1.0 and 10.0mg/l.