Single-laboratory validation of a method for ergosterol determination in cereals

Area of Science:

• Food Science and Technology
• Analytical Chemistry
• Mycology

Background:

• Ergosterol (ERG) is a key sterol biomarker produced by fungi, absent in most plants.
• Fungal presence in cereals can lead to significant quality issues, including mycotoxin contamination.
• Accurate detection of fungal presence is crucial for food safety and quality control in cereal products.

Purpose of the Study:

• To develop and validate a robust analytical method for quantifying ergosterol (ERG) in various cereal matrices.
• To establish the reliability and accuracy of the developed method for detecting fungal contamination in cereals.

Main Methods:

• Ergosterol extraction from cereal samples using refluxing with methanol-sodium hydroxide.
• Purification of ergosterol via hexane extraction and silica gel cartridge chromatography.
• Separation and quantification of ergosterol using reverse-phase high-performance liquid chromatography (HPLC).

Main Results:

• High 'within-day' recoveries (92-99%) with low relative standard deviations (RSDs: 3.2-6.5%) for ergosterol at low levels.
• Consistent 'between-day' recoveries (97%) and acceptable RSDs (4.2-10.2%) demonstrating method reproducibility.
• Overall average recoveries ranging from 81-105% across a broad concentration range (1.0-100.0 mg kg(-1)) with RSDs of 3.9-16.3%.

Conclusions:

• The developed single-laboratory validated method provides accurate and reliable quantification of ergosterol in cereals.
• This validated HPLC method is suitable for routine analysis, enabling effective detection of fungal contamination and potential mycotoxin risks in cereal products.