Simple fluorescence method for rapid estimation of aflatoxin levels in a solid culture medium

Area of Science:

• Food Science
• Mycology
• Analytical Chemistry

Background:

• Aflatoxins are toxic secondary metabolites produced by certain Aspergillus species.
• Accurate quantification of aflatoxins is crucial for food safety and quality control.
• Existing methods for aflatoxin detection can be time-consuming or require complex equipment.

Purpose of the Study:

• To develop and validate a direct, fluorescence-based method for estimating aflatoxin concentrations in agar media.
• To assess the correlation between agar fluorescence and known aflatoxin levels.
• To determine the utility of this method in differentiating aflatoxin-producing capabilities of Aspergillus isolates.

Main Methods:

• Aflatoxin-producing Aspergillus isolates were cultured on an agar medium.
• Cultures were incubated, and fluorescence was elicited using UV light (365 nm).
• Fluorescence intensity (≥450 nm) was measured photometrically using a scanning densitometer.

Main Results:

• Agar fluorescence showed a strong direct correlation (r² = 0.89 ± 0.05) with aflatoxin concentration (0–18.7 µg/g).
• The method detected aflatoxin concentrations as low as 50 ng/g.
• The technique effectively distinguished between Aspergillus isolates with varying aflatoxigenic potentials.

Conclusions:

• Direct quantification of agar fluorescence provides a reliable and sensitive method for estimating aflatoxin concentrations.
• This technique offers a potentially faster and simpler approach for assessing aflatoxin contamination and fungal toxigenicity.
• The method demonstrates practical application in food safety and mycotoxin analysis.