ABSTRACT
Microbiological air quality assurance is a relevant assessment carried out to determine the microbial load and composition of the air microflora. Students spend approximately 6-8 hours in the lecture halls, the air breathed in has a direct impact on their performance and productivity. Inhalation of contaminated air is risky to the health and comfort of occupants. The aim of this study was to assess the microbial load of Lecture rooms in the Faculty of Life Sciences, University of Benin. The assessment was carried out by sampling the air using settle plate method; from Lecture rooms in the Faculty. Culture media used were nutrient agar, mannitol salt agar, mackonkey agar and potato dextrose agar. Sampling was carried out every month for 2 months. The results showed that the lecture room with the highest bacterial, coliform and Staphylococci count was PBB LR with values 4.84 ± 0.82 x 103 , 4.30 ± 0.51 x 10 3 and 3.52 ± 0.89 x 103 cfu/m3 respectively in month 2. The highest fungal count of 1.57± 0.68 x 103 was from MCB LR in month 1. The identified bacterial isolates were Lactobacillus delbrueckii, Aeromonas hydrophilia, Enterobacter intermedius, Staphylococcus epidermis, Serratia liquefacias, Pseudomonas sp, Micrococcus luteus, Acineobacter baumanii, Lactobacillus fermenti, Serratia marcese, Aeromonas veronii., Streptococcus sp., Staphylococcus aureus, Corynebacterium sp. The isolate with the highest frequency of occurrence was Lactobacillus delbrueckii. Identified fungal isolates were Penicillium, Aspergillus, and Alternaria spp. Bacterial isolates with the highest virulence factors of 100 % was Aeromonas veronii. The antibiotic susceptibility pattern showed that all Gram negative bacterial isolates were susceptible to Sparfloxacin antibiotic. Isolate with the highest MAR index of 0.6 was Acinetobacter baumanii. To maintain air quality, constant monitoring of parameters like temperature and humidity that favour the growth of these organisms or their presence in the air, and reducing the number of occupants, proper ventilation system, proper building plan and design and proper clean up regularly should be practiced
