Analytical Methods for Identification and Quantification of Quinoa Saponins: A Review

Area of Science:

• Phytochemistry
• Analytical Chemistry

Background:

• Quinoa saponins (SAPs) are complex mixtures from *Chenopodium quinoa* seed coats.
• SAPs possess anti-inflammatory, hypocholesterolemic, antifungal, and cytotoxic properties, with potential pharmaceutical and biopesticide applications.
• Their amphiphilic nature allows use as natural emulsifiers.

Purpose of the Study:

• To review analytical methodologies for quinoa saponins (SAPs) from 1981-2024.
• To discuss identification and quantification challenges and considerations.
• To highlight the importance of method selection for accurate analysis.

Main Methods:

• Gas Chromatography-Mass Spectrometry (GC-MS)
• Liquid Chromatography-Mass Spectrometry/Mass Spectrometry (LC-MS/MS)
• Nuclear Magnetic Resonance (NMR) spectroscopy
• Mass Spectrometry (MS)
• High-Performance Liquid Chromatography with Diode-Array Detection (HPLC-DAD)

Main Results:

• GC-MS and LC-MS/MS are widely used for SAP profiling.
• Full structural elucidation necessitates isolation followed by NMR and MS analysis.
• Quantification is challenging, often relying on relative estimations; HPLC-DAD, LC-MS, and GC-MS/MS offer higher sensitivity.

Conclusions:

• Accurate identification and quantification of quinoa SAPs depend heavily on the chosen analytical method and reference standard.
• Advances in analytical techniques are crucial for unlocking the full potential of quinoa saponins.
• Further research into standardized quantification methods is warranted.