Effect of Crude Engine Oil and Aromatic Fractions of Pleurotus Pulmonarius Fries (Quelet)

The ability of two white rot fungi, Pleurotus ostreatus and P. pulmonarius, to degrade crude and used engine oil was examined for six months. In 9 9 4 cm (350 cm3) jam bottles, 100 grams of sterilized soil were weighed and wet with 75% distilled water (w/v). They were then completely mixed with bonny light crude oil and used motor oil at various concentrations (0%, 5%, 10%, 15%, 25%, and 30%), individually. Then, using a sterile cork borer, two agar plugs of a strongly growing P. ostreatus and P. pulmonarius mycelium were inoculated into each bottle. For six months, the bottles were kept at room temperature. After drying, the mycelia-ramified waste was removed from the soil and examined for physicochemical characteristics such total hydrocarbon content (THC), organic matter, carbon, nitrogen, phosphorus, and potassium. After six months, both contaminated and inoculated soils had higher levels of organic carbon, nitrogen, and phosphorus. However, during the experiment period, these soils had a drop in THC, pH, and potassium. In soils contaminated with 20% of crude and engine oils, respectively, P. ostreatus lowered the initial THC to 8% and 9%, which was less than P. pulmonarius. The two white rot fungus may be used in the bioremediation of soils contaminated with old motor oil and bonny light crude

Changes in antioxidant enzyme activities in Eichhornia crassipes (Pontederiaceae) and Pistia stratiotes (Araceae) under heavy metal stress

Whole plants of Eichhornia crassipes and Pistia stratiotes were exposed to various concentrations (0, 0.1, 0.3, 0.5, 1.0, 3.0 and 5.0 mM) of 8 heavy metals (Ag, Cd, Cr, Cu, Hg, Ni, Pb and Zn) hydroponically for 21 days. Spectrometric assays for the total activity of catalase, peroxidase, and superoxide dismutase in the leaves were studied. At the end of the experimental period, data referred to metal treated plants were compared to data of untreated ones (control). Heavy metals increased the activity of catalase, peroxidase and superoxide dismutase in both species and there was differential inducement among metals. Overall, Zn had the least inducement of antioxidant enzymes in both species while Hg had the highest inducement. The increase in antioxidant enzymes in relation to the control plants was more in E. crassipes than P. stratiotes. The results showed that E. crassipes tolerated higher metal concentrations in a greater number of metals than P. stratiotes

Insecticidal activities of the African yam bean seed lectin on the development of the cowpea beetle and the pod sucking bug

The cowpea beetle, Callosobruchus maculatus, and pod-sucking bug, Clavigralla tomentosicollis, are two of the major insect pests of cowpea in Africa. A lectin was purified from the seeds of the African yam bean (AYB), Sphenostylis stenocarpa, by affinity chromatography on Galactosc-Sepharose 4B. The purified AYB lectin (AYBL) was tested on the two insect pests of cowpea. When C. maculatus larvae were fed on artificial cowpea seed containing 0.2, 2, and 5% (w/w) of dietary lectin, larval mortality ranged from 30 to 88% and delay in number of days to first emer gence from 4-13 days. When AYBL was tested on C. tomentosicollis, nymphal mortalities ranged from 76 to 81% at 1% and 87 to 94% at 2%. From 4 to 8%, no nymph survived up to six days after infestation. The results of these insect bioassays provided a scientific basis for isolating a lectin gene from AYB for the transformation of cowpea