The impact of acute exposure of Clarias gariepinus juveniles to commonly used herbicides, glyphosate and paraquat was evaluated through changes in fish mortality and biochemical indeces. Juveniles of the African catfish were exposed to varying acute concentration of glyphosate and paraquat. After 96 h of exposure, the 96 h LC 50 for paraquat was found to be 0.07 mg/l while that of glyphosate was found to be 0.530 mg/l. After the exposure period, some enzymes were assayed for in fish liver using a combination of conventional methods and commercially available kits. Comparing with the control, ANOVA analysis revealed that there were significant (p < 0.05) increases in the activities of all enzymes assayed for alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH) and alkaline phosphatase (ALP). There were also significant (p < 0.05) increases in the activities of the antioxidant enzymes: catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx) and in lipid peroxidation, which was measured by thiobarbituric acid substances (TBARS). The result revealed that glyphosate and paraquat have the ability to modulate certain fish biochemical parameters and can therefore serve as reliable indicators of toxicity in environmental impact assessment programmes.

Water hyacinths pose serious challenges to humanity and the environment. Considering the enormity of the menace associated with the growth and spread of the plant and the difficulty in achieving a single, generally acceptable control method, it is becoming increasingly imperative to explore the potentials of the plant. New water hyacinth-related articles are regularly being published. Recently published articles about the plant were accessed, and the information in these articles is presented in the context of the pros and cons of the plant. Some of the benefits that can be derived from the plant include biogas and biofuel production, medicinal functions, vermicomposting, compost production, and bioremediation. However, clogging of waterways, obstruction of water transportation, and fishing activities; breeding grounds for pests and diseases; and reduction of water quality, loss of biodiversity, and economic downturn in areas invaded by the plant are problems associated with it. The peculiarity in the invasiveness of each situation should determine whether or not the growth of the plant is a problem, especially if the opportunity to harness the potentials of the plant exists. There are three major methods for controlling the plants when control becomes inevitable: mechanical, chemical, and biological. To achieve the best control, integrating two or more control methods is advised.

This study was carried out to determine the antiplasmodial activity of leaves of Moringa oleifera. Cold extraction method was carried out on grinded leaves to prepare the crude ethanolic and n-hexane extracts. Mice models (Mus musculus) were passaged with chloroquine resistant Plasmodium berghei, which are similar in morphology, physiology and life cycle to P. falciparum that infect humans. Stock solutions of 5 mg/mL 5% DMSO were prepared and the extracts were administered at different treatment concentrations, 50 mg/kg, 100 mg/kg and 200 mg/kg body weight over 4 days. Positive and negative control groups, Chloroquine diphosphate (25 mg/kg) and 5% DMSO, respectively were set up. Crude ethanolic and n-hexane extracts of M. oleifera showed anti-plasmodial activity at the three different concentrations used. Both crude ethanolic and nhexane extracts of M. oleifera leaves showed a significant inhibition of parasitaemia (p < 0.05) ranging from 74.7 to 95.6% for ethanolic extract and 59.3 to 87.9% for n-hexane extract. EC50 value of crude ethanolic and n-hexane extracts were 32 mg/kg and 42 mg/kg body weight, respectively. M. oleifera showed potential for possible future use as an alternative to some conventional drugs.

Studies were carried out on deteriorated apples obtained from the Just Rite supermarket, Ota, Ogun State, Nigeria, to isolate microorganisms associated with post-harvest deterioration of apple (Malus domestica) fruits. The bacterial species were identified using microscopy, morphology and various biochemical tests while macroscopy and morphology was used to identify the fungi isolated. The ability of the isolate to elaborate extracellular amylase and protease were tested for. Results revealed Aspergillus niger and Aspergillus flavus as the fungal species while the bacterial species isolated were Bacillus spp and Micrococcus spp. All the isolates except Aspergillus niger produced amylase in substantial amount. Micrococcus spp, Aspergillus niger and Aspergillus flavus produced protease. The results of this investigation if combined with further studies can be used in identifying organisms which could be used as a biological method in the control of apple pathogens.

Direct and indirect contamination of the aquatic environment by pesticides results in a decrease in fish productivity and may elevate concentrations of undesirable chemicals in edible fish tissues. The effects of long-term exposure of Clarias gariepinus juveniles to sublethal concentrations of glyphosate and paraquat, two commonly used herbicides, for eight weeks were investigated using three concentrations of the 96 h LC 50 of each herbicide: 3.5, 7 and 14 µg l −1 for paraquat, and 26.5, 53 and 106 µg l −1 for glyphosate. Enzyme assay and histological analysis were conducted every fortnight. Significant increases in the activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), alkaline phosphatase (ALP) and hepatocyte vacuolation in the livers of the exposed fish confirms the toxicity of the herbicides, and thus could be useful tools in environmental monitoring.