Oligonucleotide microarray for the identification of potential mycotoxigenic fungi

Area of Science:

• Food safety and microbiology
• Mycotoxin detection
• Molecular diagnostics

Background:

• Mycotoxins from fungi contaminate food commodities, posing risks to human and animal health.
• South Africa faces continuous challenges with mycotoxin contamination in food.
• Accurate identification of mycotoxigenic fungi and their toxins is crucial for food safety.

Purpose of the Study:

• To develop a diagnostic DNA microarray for identifying common food-borne fungi.
• To detect genes responsible for mycotoxin production in fungi.
• To provide a tool for assessing mycotoxin risks in food commodities.

Main Methods:

• Oligonucleotide probes were designed targeting elongation factor 1-alpha (EF-1 alpha) and internal transcribed spacer (ITS) regions for fungal identification.
• Probes targeting mycotoxin synthetic pathway genes were identified from public domain data.
• Selected probes were spotted onto microarray slides for simultaneous analysis.

Main Results:

• The study analyzed 40 potentially mycotoxigenic fungi and their toxin-related genes.
• The developed microarray successfully identified fungal strains and toxin-producing genes.
• The method allows for the analysis of both pure cultures and complex food samples.

Conclusions:

• The diagnostic DNA microarray effectively identifies potentially mycotoxigenic fungi and their toxin-producing genes.
• This tool has potential applications in microbiological laboratories for routine testing.
• It can be used to analyze laboratory samples and maize-derived foods for mycotoxin risks.