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This study was carried out to determine the bacterial and fungal flora of soils contaminated with used automobile engine oil at a mechanic workshop at AKAD community, Akure, Ondo State, Nigeria, with the aim of testing  their ability to degrade diesel oil. Isolation and identification of microbes were done using standard microbiological techniques. Oil degrading activity of the isolates were assayed for using Bushnell Haas broth (BHB) supplemented with 1% diesel oil.

Genome editing is used to make targeted modifications to the genome of eukaryotic cells. There are many potential applications of genome editing in human pluripotent stem cells (hPSCs) including the generation of knockout and reporter cell lines. This protocol describes a system for efficient genome editing in hPSCs using engineered transcription activator-like effector nucleases (TALENs) or clustered regularly interspaced short palindromic repeat (CRISPR) technology.

Prolonged culture of pluripotent and multipotent stem cells exposes the cells to strong selection pressures, often resulting in genomic alterations. Any genetic manipulation of the cells may further jeopardize their genomic stability. Genomic aberrations affect the differentiation capacity of stem cells, their stem cell identity and their tumorigenicity, and should thus be routinely evaluated for their proper use in basic research and in clinical trials.

The directed differentiation of human embryonic stem cells (hESCs) or human induced pluripotent stem cells (hiPSCs) into hepatocytes could facilitate a rational study of the molecular mechanisms underlying human liver development as well as provide a renewable source of exogenous hepatocytes for drug toxicity testing and cell-based therapeutics. Moreover, if hepatocytes were produced from hiPSCs originating from patients with inborn errors of hepatic metabolism, such cells could be used for modeling liver disease.

The pluripotency of embryonic stem (ES) cells is the result of a highly dynamic equilibrium that is controlled by a complex network of transcription factors that confer unique transcriptional properties to ES cells. Regulation of gene expression appears to correlate with the presence of dual chromatin marks called bivalent domains at the promoters of poised developmental genes. These marks keep differentiation genes silenced but poised and ready to be activated or permanently repressed during differentiation.

‘Burukutu’ which is an indigenous alcoholic drink has been shown to be rich in bacterial diversity, with a total of thirteen (11) bacterial species isolated from the three stages of production (namely: steeping, mashing and maturation) sampled from two different selling points in Ilorin, metropolis. The bacterial species isolated are Streptococcus sp; Lactobacillus sp; Bacillus sp; Pseudomonas sp; Klebsiella sp; Staphylococcus sp; Enterococcus sp; Escherichia coli; Proteus sp; Leuconostoc sp and Micrococcus sp.

The piscicidal potential of water-extract mesocarp of Azardirachta indica was investigated in static biossay experiment with continuous aeration to determine its acute toxicity. The 96-hLC50 was 97.42mg/l while the threshold value was 31.12mg/l. The extract led to an initial increase in opercula ventilation rates which then decreased significantly. The computed regression equation (y) = 4.624 + 6.352 Logc. (r=0.72) and the fish exhibited respiratory distress, loss of balance and erratic swimming prior to mortality. The usefulness of A. indica as piscicidal plant is discussed.

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.