The extensive use of pesticides is one of the major causes of pollution of soil and water environments. The current method for removing such contaminants from the environment through biodegradation has been shown to be more effective than any other method. Three pesticide degrading bacteria were isolated and identified through cultural and biochemical tests as strains of Pseudomonas aeruginosa, Serretia marcescens and Klebsiella oxytoca. Their growth in mineral salt medium supplemented with 20mg/l of Chlorpyrifos was monitored at optical density of 600nm. The result showed that Pseudomonas aeruginosa had maximum growth in ten days, while Serretia marcescens and Klebsiella oxytoca recorded highest growth after six days of incubation. HPLC analysis of the residual Chlorpyrifos after 14 days incubation showed that Pseudomonas aeruginosa was able to degrade 60% of the pesticide; Klebsiella oxytoca degraded 54%, while Serretia marcescens had 53% reduction of the pesticide concentration in the mineral salt medium. The results of this research indicated that the isolated bacteria can be used for bioremediation of Chlorpyrifos contaminated soil and water ecosystems.

In-vitro assessment of the antibacterial quality of four commonly used brands of herbal toothpastes in comparison with their corresponding non-herbal toothpastes on Streptococcus mutans was examined. Eight brands of commercially available toothpastes comprising of four herbal and non-herbal brands respectively were purchased in a local market in Awka South, Anambra State, Nigeria. The herbal brands selected were designated AH, BH, CH and DH and their respective non-herbal brands designated ANH, BNH, CNH and DNH served as positive controls. The use of distilled water served as negative control. The antibacterial activity evaluation was performed using agar well diffusion method. Different concentrations of toothpastes were made by 2-fold serial dilution method using sterile distilled water as diluents. Inhibition zones were measured in millimeters after 24hrs. Among the non-herbal toothpastes, triclosan containing toothpaste gave the highest zone of inhibition compared to non-triclosan toothpastes. The herbal toothpaste of each brand gave better inhibition result in comparison with their corresponding non-herbal brands. BH toothpaste gave maximum inhibition followed by AH, CH and lastly DH toothpastes. The result of this study indicates that herbal toothpastes are marginally better in inhibiting the growth of Streptococcus mutans; although both herbal and non-herbal toothpastes were equally effective in reducing pathogenic plaque and maintaining oral hygiene.

Cocoyam (Colocasia esculenta) corms, purchased from a local barn in Awka, Anambra state, showing spoilage symptoms were examined for rot associated with fungal pathogens. The spoilage organisms were isolated from the corms by explanting the spoilt tissues obtained aseptically onto Sabouraud Dextrose Agar supplemented with chloramphenicol an antibacterial agent. The developing isolates were purified by repeated subculture and identified macroscopically and microscopically using the slide culture technique. The organisms recovered from spoilt cocoyam were Aspergillus niger, Rhizopus stolonifer, Mucor circinelloides, Penicillium cyclopium and Fusarium oxysporum. The rot due to Rhizopus, Mucor and Fusarium were extensive resulting in complete maceration of cocoyam tissues. The pathogenicity test also showed that the above organisms were responsible for cocoyam spoilage. These spoilage organisms may have had access into these cocoyam corms through air, wounds, working equipment (for harvesting) and pests. Proper care should be taken in the handling of these corms as some of these spoilage fungi are known to have negative impact on both humans and livestock because they produce mycotoxins.