Natural antifouling compound production by microbes associated with marine macroorganisms — A review

In the marine environment, all hard surfaces including marine macroorganims are colonized by microorganisms mainly from the surrounding environment. The microorganisms associated with marine macroorganisms offer tremendous potential for exploitation of bioactive metabolites. Biofouling is a continuous problem in marine sectors which needs huge economy for control and cleaning processes. Biotechnological way for searching natural product antifouling compounds gained momentum in recent years because of the environmental pollution associated with the use of toxic chemicals to control biofouling. While, natural product based antifoulants from marine organisms particularly sponges and corals attained significance due to their activities in field assays, collection of larger amount of organisms from the sea is not a viable one. The microorganisms associated with sponges, corals, ascidians, seaweeds and seagrasses showed strong antimicrobial and also antifouling activities. This review highlights the advances in natural product antifoulants research from microbes associated with marine organisms.

Levels of some heavy Metals in Cocoyam ( Colocasia esculentum ) grown on Soil receiving Effluent from a Paint Industry

The levels of some heavy metals in soil samples and tubers of cocoyam ( Colocasia esculentum ) grown on soil receiving paint wastes (PWS) has been investigated using Atomic Absorption spectrophotometer (Unicam 939/959 model). Similar analyses were carried out for the same plant from a control area. The studies revealed that although the P.W.S contained abnormally high levels of Pb (474.14mgkg-1) and Cu (137.85mgkg-1). The paint waste tuber (PWT) recorded low levels of these metals: Pb (2.13mgkg-1) and Cu (13.85mgkg-1) respectively. Correlation analysis tested at 0.05 level of significance show that no significant correlation existed between the metals levels in the soil and the level in the tuber. In all cases the levels of the metals in the tubers were well below the upper limit documented for unpolluted plant. The results however suggest the ineffectiveness of the use of Colocasia esculentum as a bioindicator for heavy metal pollution in soil.

Infestation of Tunga penetrans in villages near Zomba Central Hospital

An outbreak of Tunga Penetrans (Jigger Flea) infestation affecting a number of villages near to a Central Hospital in Malawi is described. Due to the large number of affected individuals, high parasitic load, and extended duration of infection an alternative to the recommended approach of surgical removal of the flea was required. Benzyl benzoate paint and liquid paraffin had been used in local Primary Healthcare settings previously and topical treatment with antiparasitic agents has been advocated in the literature, particularly for severe infestation. Benzyl benzoate and liquid paraffin were applied topically to four adults with numerous jigger flea burrows, and their progress assessed regularly. After completion of 7 days of treatment patients noted that fleas were dislodging spontaneously, and that embedded parasites had not increased in size to the same extent that untreated fleas had in previous infestations. Following confirmation of the viability of its implementation in a resource-poor setting, this treatment regimen has subsequently been adopted by the local branch of the District Health Office for distribution to infected communities.