Pyrrolizidine alkaloids in bee pollen identified by LC-MS/MS analysis and colour parameters using multivariate class...

Area of Science:

• Food Chemistry
• Analytical Chemistry
• Food Safety

Background:

• Pyrrolizidine alkaloids (PAs) and their N-oxides (PANOs) are toxic compounds found in various plants.
• Bees can collect pollen from these plants, potentially contaminating bee pollen with PAs/PANOs.
• Monitoring PA/PANO levels in bee pollen is crucial for ensuring food safety and quality.

Purpose of the Study:

• To develop and validate a method for monitoring PAs/PANOs in bee pollen.
• To investigate the correlation between bee pollen color and PA/PANO content.
• To evaluate the potential of instrumental color analysis as a screening tool for PAs/PANOs in bee pollen.

Main Methods:

• A liquid chromatography-mass spectrometry (LC-MS/MS) method was developed and validated for quantifying 17 PAs/PANOs.
• CIE-L*a*b* color coordinates were measured in bee pollen samples.
• Receiver operating characteristic (ROC) analysis and supervised canonical discriminant analysis were employed.

Main Results:

• Lightness (L*) and yellowness (b*) of ground bee pollen were significantly correlated with PA/PANO content.
• Specific L* and b* cut-offs predicted a higher risk of detecting PAs/PANOs above 84 μg kg⁻¹.
• Supervised models successfully distinguished between pollen with and without PAs/PANOs.

Conclusions:

• Instrumental color measurements, particularly lightness and yellowness, show promise for screening bee pollen for PAs/PANOs.
• Color analysis coupled with supervised models can serve as a rapid, cost-effective preliminary test.
• This approach can help prioritize samples for confirmatory LC-MS/MS analysis, improving efficiency in food safety monitoring.