MYCOLOGICAL EXAMINATION OF THE INDOOR AIR AND SURFACES OF HOUSEHOLD REFRIGERATORS

ABSTRACT

Domestic refrigerator is a low temperature appliance that is often used in homes for preservation and storage of food products. It is also known as household refrigerator. It is often a popular method of controlling the growth of microorganisms. Despite this, food contamination could often result from contamination of the refrigerator with fungal species. This study focused on assessing the quality of refrigerators by mycological examination of indoor air and surfaces of household refrigerators. Twelve indoor air and surface samples each were taken from household refrigerators across Benin City. The samples were subjected to standard microbiological analysis. During this study, various fungal genera were isolated including Cladosporium, Aspergillus, Penicillium, Fusarium, Trichoderma, Rhizopus and Candida. Of these genera, the most occurring was Penicillium(83.3%) in indoor air samples and Penicillium(50%), Aspergillus(50%) in surface swab samples. The log heterotrophic fungal count ranged from 4.4±0.8 in those who cleaned yearly to 1.3±0.2 in those who cleaned daily. The Log10 CFU/cm2 heterotrophic fungal count based on the amount of electricity supply received was ascertained. This study showed that there was a progressive decline in fungal count with increasing electricity supply. The log heterotrophic fungal count ranged from 3.2±0.7 to 1.1±0.4 log CFU/cm2 . Furthermore another important parameter, the log heterotrophic fungal count based on the presence of alternative power supply in the absence of electricity was considered. Interestingly, the Log10 CFU/cm2 heterotrophic fungal count of the of refrigerators ranged from 2.60±0.5 to 3.4±0.3 CFU/cm2 in those who chose rarely and regularly, respectively. The highest log The multiple antifungal resistance index of the isolates were carried out with Rhizopus having the highest MAR Index of all isolates. this study showed in conclusion that corresponding with previous research, there lies a huge public health risk in fungal contamination of refrigerators which could result in in food deterioration and food borne illnesses.