Microbial deterioration of surface paint coatings.

Abstract

Bacterial and fungal species associated with the normal and deteriorated painted surface in Owerri, Imo State were isolated and identified. The bacteria genera isolated were Pseudomonas, Bacillus, Micrococcus, Staphylococcus, Enterobacter and Streptomces, whereas the fungal genera isolated were Rhizopus, Penicillium, Cladosporium,. Aspergillus, Alternaria, Fusarium, and Curvularia. More bacterial and fungal isolates were obtained from biodeteriorated surfaces than normal painted surfaces. The occurrence of these microbial isolates in normal : deteriorated painted surfaces were found to be Pseudomonas (90:100%), Bacillus (80:100%), Rhizopus (60:100%) and Aspergillus flavus (50:90%) Penicillium, Staphylococcus, Enterobacter, Aspergillus niger, Cladosporium, Alternaria Streptococcus, Fusarium, Curvularia and Micrococcus occurred only between 20 and 70%in the biodeteriorated samples. Bacillus sp., Pseudomonas sp., Rhizopus sp. and Aspergillus niger were isolated from undeteriorated (normal) painted surfaces. Besides the organisms isolated from normal pain, Penicillium sp., Cladosporium, Aspergillus flavus, Alternaria sp., Fusarium sp., Micrococcus sp., Staphylococcus aureus Enterobacter sp., and Streptococcus sp. were isolated in the deteriorated paint. None of the isolates was able to grow on fresh emulsion paint films. This study has established the microbial flora of deteriorated painted surfaces in the tropics. Global Jnl Pure and Applied Sciences Vol.10(4) 2004: 485-490