ISOLATION AND IDENTIFICATION OF FUNGI (YEAST AND MOLD) FROM DAMBUN NAMA AND THEIR SUSCEPTIBILITY TO CHITOSAN

ABSTRACT

This study was conducted with the aim of isolating and identifying fungi present in “Dambun nama” purchased from Abuja metropolis and test their susceptibility to chitosan. Samples purchased were analysed for the presence of fungi using standard procedures. Potato dextrose agar was used in isolating fungal isolates from Danbun nama samples using pour plate method. The total fungal count was then estimated after fungal growth was observed. The proximate composition of the samples were evaluated by estimating the levels of moisture, ash, fat, protein and nitrogen free extract. Various concentrations of chitosan solutions were also tested in vitro to determine the activity against the various fungal isolates. Results revealed that the fungal isolated from Danbun nama samples of chicken and beef source were Aspergillus parasiticus, Saccharomyces spp and Aspergillus flavus. The total fungal count in Dambun nama ranged from 7.00±0.58×10⁴ - 50.33±0.88×10⁴cfu/g. The percentage moisture content in Dambun nama ranged from 6.37±0.02-8.83±0.25 %. Percentage ash content in Dambun nama ranged from 3.70±0.09-5.55±0.03%. Percentage fat content in Dambun nama ranged from 11.94±0.02-15.71±0.07%. The percentage protein content in Dambun nama ranged from 55.25±0.50-64.21±0.03%. The percentage nitrogen free extract in Dambun nama ranged from 8.52±0.21-22.25±0.05%. Antimicrobial activity of chitosan against the isolates showed that 5.8mg/l chitosan solution exhibited zones of inhibition of 3.07±0.07mm, 3.47±0.29mm and 3.60±0.23mm for Aspergillus flavus, Aspergillus parasiticus and Saccharomyces cerevisiae respectively. The presence of these potential pathogenic fungi in Danbun nama suggests the need for proper care in the course of preparation and handling so as to prevent the likelihood of foodborne diseases transmission.