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theses

Quinoa (Chenopodium quinoa Willd.) is an Andean subsistence crop rich in bioactive secondary metabolites, particularly phytoecdysteroids (PEs) and flavonoid glycosides (FGs). Innovations designed to harness and investigate the pharmacological value of quinoa through simple, food-grade technologies may facilitate the development of functional foods and nutraceuticals from this crop that can combat global challenges in human health and sustainable development. The transdisciplinary aims of the thesis were to: (1) review the technological innovations associated with quinoa’s use, contextualized within the framework of the crop’s socioeconomic history and future implications for sustainability; (2) develop a novel method to leach and concentrate bioactive phytochemicals from quinoa seeds; (3) chemically characterize the resultant quinoa leachate (QL); (3) determine the pharmacological activities of QL as they relate to its prospective nutraceutical and cosmetic applications; (4) assess the variation in phytochemical content among multiple sources of quinoa seeds; (5) explore the role that the “screens-to-nature” (STN) bioexploratory approach can play in sustainable development initiatives among indigenous quinoa-producing communities in the Andes. A one-step, non-destructive, food-grade procedure was developed to leach PEs and FGs from intact (un-macerated) quinoa seeds in 70% ethanol for 4 h at 80 °C, while preserving the color, structure, and form of post-leached seeds. The liquid leachate was dried to a powder termed quinoa leachate (QL) and chemically characterized via high performance liquid chromatography (HPLC)-mass spectrometry (MS). PE content was concentrated 17.5-fold in QL compared to initial levels in the seed. QL lowered fasting blood glucose levels in hyperglycemic mice and reduced matrix metalloproteinase (MMP) activity and expression in vitro, suggesting its potential applications in diabetes management, skin care, and other aspects of human health. Using leaching and HPLC-MS analysis, over 4-fold differences in PE and FG content were observed among seventeen distinct sources of quinoa seeds. Furthermore, Chilean highland genotypes demonstrated significantly higher FG content than lowland genotypes, indicating the potential to breed and market quinoa varieties with enhanced phytoactive content. QL and quinoa seed by-products demonstrated a range of biochemical activities in STN assays deployed in Chile, illustrating the potential role of the STN bioexploratory approach in community-driven projects to improve local nutritional and agricultural strategies in the Altiplano. Further research and development of the functional value of quinoa may play an important role in human health and environmental sustainability at the local and global scale.

ETD_5826

Ph.D.

Includes bibliographical references

by Brittany Leigh Graf

doi:10.7282/T34M931N

ETD doctoral

The author owns the copyright to this work.