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Aspergillus niger popularly known as industrial workhorse due to its fitness for industrial fermentation, has the potentials to secret citric acid. In view of surges in demand and growing markets for citric acid, the major attempt in this work was to determine how the product titres can be maximized. A. niger strains were isolated from various food substances. These strains were exposed to UV radiation at 356nm followed by subsequent subjection of the mutant strains to a medium containing chlorate as mutagen.

Microbial activities contribute significantly to the global economic burden of corrosion. The sulphatereducing bacteria (SRB) are major cause of biocorrosion in anoxic environments. This study investigated the corrosion inhibition efficiency of Gmelina arborea extracts against corrosion of carbon steel caused by SRB isolated from injection and produced water from Bonga oilfield. The SRB isolation, antimicrobial assay and corrosion experiments were carried out in a Coy anaerobic chamber.

Insects of the taxonomic order Coleoptera are recognized for considerable cellulolytic activity in their digestive tract. However, the cellulolytic activity of the gut microbiome of the African palm weevil (Rhynchoporus phoenicis), has not been reported. Thus, this study aimed at isolating cellulose degrading bacteria from the gut of the insect’s larva and assessingtheir cellulolytic activities. The larva of the insect was dissected and inoculated in carboxymethylcellulose-Congo red (CMC-CR) agar medium and incubated at room temperature (28±2) for 14 days.

This study assessed the air pollution tolerance index (APTI) of four plants around the Seplat Gas Flow Station in Sapele, Delta State. Fresh leaves of the plants were collected, weighed, dried and extracts were made. Standardized procedures for determining APTI were adopted. The physio-biochemical characteristics of the four plant species ranged from; pH 4.57–5.36, chlorophyll content 0.17-0.45 mg/g, RWC 41.0%–80.0%, ascorbic acid: 0.91 – 1.58 mg/g, while APTI varied from 5.75 – 6.99.

Fish feed account for over 70% of the total cost of fish production, this is due to the high cost of its components most especially fishmeal which is highly expensive and imported. Trials to replace costly fishmeal in fish diets with maggot meal have shown promising results. However, wide use of maggot meal in aquaculture feed industry is limited due to unavailability of adequate amounts of maggot meal. Therefore, this study was carried out to determine the best possible substrates and attractants combination for production of housefly larvae.

An experiment was designed and carried out to assess the growth responses of Heterobranchus bidorsalis fingerlings fed graded levels of toasted Vigna subterranean based diets with the aim of establishing the best inclusion level of Bambara groundnut seed meal. Ground decorticated toasted bambara groundnut (BG) was incorporated as a nonconventional feedstuff at 0% (T1); 10% (T2); 20% (T3); 30% (T4) and 40% (T5) level of replacement for soyabean for treatment one to five respectively.

The effect of the ethanol extract of Aloe barbadensis root on selected serum biochemical parameters was investigated.Sixty male Wistar rats were randomly selected and administered 100, 200 and 400 mg/kg of the extract and 0.2ml/kg of distilled water (control) for 14 days. The results of the liver marker enzymes revealed that there were non-significant changes (p>0.05) in alkaline phosphatase (ALP), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels on days 1, 7 and 14 of treatment.

The zooplankton community in association with some physical environmental factors was studied for six (6) months. A total of 5,303 individuals made up 17 species belonging to 3 families was recorded. Rotifers had the highest species composition of 41.06%, followed by Copepods and Ciliates with 29.41% and 23.53% respectively. There was no significant relationship in zooplankton composition across the stations and between seasons (P<0.05).

Desplatsia dewevrei (De Wild. & Th. Dur.) Burret fruits were investigated for possible anti-fertility and profertility activities by hematological, biochemical and hormonal assays using Wistar rats of both sexes for 6 weeks. Methanol extract of Desplatsia dewevrei fruits was administered orally at 50 and 100 mg/kg. Results show that concentrations above 50 mg/kg interfered with the reproductive development of the liter (fetus) in female rats. While in male rats, doses above 50 mg/kg posed adverse effect on sperm count and sperm motility.

Flood can be seen as a process that bring about a short-term immersing of a land with water that does not ordinarily occur. It is one of the most common environmental hazards in developing countries like Nigeria. Flooding, a recurrent events in Nigeria occur mostly in locations that are flat or low lying especially places with inadequate or no surface drainages, or where existing ones have been filled with refuse and other sediments. The exposure to flooding is due to a range of socio-economic factors, like income, occupation, information technology, access to loan facilities, etc.