Improving selenium extraction by sequential enzymatic processes for Se-speciation of selenium-enriched Agaricus...

Area of Science:

• Food Science
• Analytical Chemistry
• Biochemistry

Background:

• Selenium speciation analysis in food matrices like mushrooms is crucial for understanding bioavailability and toxicity.
• Selenized mushrooms (Agaricus bisporus) grown on selenium-enriched compost present unique challenges for sample preparation due to complex biological structures.
• Enzymatic digestion methods are increasingly explored for efficient extraction of analytes from biological samples.

Purpose of the Study:

• To investigate and compare different enzyme-based sample preparation methods for selenium speciation in selenized mushrooms.
• To evaluate the impact of proteolytic and cell wall digesting enzymes on extraction efficiency and species recovery.
• To determine the optimal enzymatic procedure for reliable selenium speciation analysis in Agaricus bisporus.

Main Methods:

• Utilized proteolytic enzymes (pronase) and cell wall digesting enzymes (Lysing enzyme, Driselase) for sample preparation.
• Compared a three-step procedure involving Lysing enzyme and pronase against a one-step proteolytic procedure.
• Monitored total selenium content using Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) for method validation.

Main Results:

• The three-step procedure using Lysing enzyme and pronase achieved the highest extraction efficiency, reaching 89% of total selenium.
• The one-step proteolytic procedure demonstrated superior recovery of intact selenium species.
• Enzyme selection and procedural steps significantly influenced both extraction yield and the integrity of selenium chemical forms.

Conclusions:

• Enzymatic sample preparation is effective for selenium speciation in selenized mushrooms.
• A trade-off exists between maximizing extraction efficiency and preserving selenium species integrity.
• The choice of enzymatic method should be guided by the specific requirements of the selenium speciation analysis.