Microbial load on medicinal plants sold in Bini markets, Nigeria

Microbiological analysis was carried out on samples of 20 medicinal plants obtained from open markets in Benin and her environs. The standard plate count technique on Nutrient agar (NA) was used to determine the total aerobic bacterial count, mannitol salt agar and Baird-Parker agar for staphylococcal count, MacConkey agar for coliform count and potato dextrose agar for fungal counts. The purified bacterial and fungal isolates were then characterized and identified. All the samples examined contained microorganisms. The bacterial count ranged from 1.0x10(3) cfu/g to 9.8x10(4) cfu/g with Aframomum meleguata, Onyokea gore and Khaya ivorensis having the highest count of 9.8 x 10(4)cfu/g; 9.4 x 10(3) cfu/g and 8.8x10(3) cfu/g, respectively and Justicia flava had the lowest count of 1.0 x 10(3) cfu/g. The fungal counts were high in all the samples examined. The bacterial isolates were identified as Staphylococcus adreus (50.0%), Staphylococcus epidermidis (25.0%), Escherichia coli (10.0%) and Bacillus subtilis (40.0%) while fungal isolates included Aspergillus niger (85.0%) and Penicillium species (50.0%). The presence of these microorganisms in the samples could be due to improper handling and storage procedures as most of the samples were kept in bags on cold floors in very humid tropical stores (stalls).