Microwave-Assisted Acid Hydrolysis vs. Conventional Hydrolysis to Produce Sapogenin-Rich Products from Fenugreek Extracts

Extraction of diosgenin using different techniques from fenugreek seeds- A review

Diosgenin, falls under the category of steroidal saponin present in fenugreek seeds (Trigonella foenum-graecum) in the amount of 0.2-09%. This compound possesses certain pharmacological characteristics like anti-inflammatory, anti-cancer, anti-oxidant etc., that render it a desirable component in the medicinal and nutraceutical industries. Various methods such as, conventional solvent extraction, green extraction methods like Soxhlet extraction, microwave-assisted extraction (MAE), maceration methods, ultrasound-assisted extraction (UAE) and supercritical fluid extraction methods are employed to extract diosgenin from fenugreek seeds. Fundamentals such as solvent choice, pre-treatment techniques, and optimization parameters, affect the diosgenin extraction process. Furthermore, the quantification of diosgenin is governed by analytical methods(chromatography and spectroscopy), underscoring the significance of standardizing diosgenin levels to set the stage for upcoming pharmacological research. However there have been very negligible resources which focuses on conventional and novel techniques for extraction of diosgenin from Fenugreek seeds. This review aims to provide combined insights into the diverse methodologies employed for diosgenin extraction from fenugreek seeds and their implications in pharmaceutical research.

Combination of Fenugreek and Quinoa Husk as Sources of Steroidal and Triterpenoid Saponins: Bioactivity of Their Co-Extracts and Hydrolysates

Saponins, both steroidal and triterpenoid, exhibit distinct bioactivities. However, they are not commonly found together in natural sources; instead, sources tend to be rich in one type or another and mainly in the form of saponins rather than the sapogenin aglycones. Developing co-extracts containing both saponin or sapogenin types would be a strategy to harness their respective bioactivities, yielding multibioactive extracts. Therefore, this study evaluates the bioactivity (hypolipidemic, antioxidant, and anti-inflammatory activities) of co-extracts from fenugreek seeds (steroidal-rich saponins) and quinoa husk (triterpenoid-rich saponins), co-extracted at varying proportions, alongside their respective sapogenin-rich hydrolysates. Pancreatic lipase inhibition increased with fenugreek content in co-extracts, especially in sapogenin-rich variants. The latter substantially interfered with cholesterol bioaccessibility (90% vs. 15% in sapogenin-rich extracts). Saponin-rich co-extracts exhibited reduced cytokine release with increased fenugreek content, while sapogenin-rich counterparts showed greater reductions with higher quinoa husk content. Limited cellular antioxidant activities were observed in all extracts, with improved post-hydrolysis bioactivity. Therefore, simultaneous co-extraction of steroidal and triterpenoid sources, such as fenugreek and quinoa husk, as well as their subsequent hydrolysis, are innovative strategies for obtaining multibioactive natural extracts.