Spigno, Sabrina (2025) A stoichiometric approach for diet assessment and gut microbial system dynamics. [Tesi di dottorato]

	Documento PDF PhD_Spigno.pdf Visibile a [TBR] Amministratori dell'archivio Download (36MB) | Richiedi una copia
	Documento PDF PhD_Thesis_Partial_Spigno_signed.pdf Visibile a [TBR] Amministratori dell'archivio Download (33MB) | Richiedi una copia

Abstract

This thesis explores parallels between organic matter decomposition in ecosystems and food digestion in humans, applying ecological concepts and methods to food science. By integrating spectroscopy, stoichiometry, and theoretical modeling, it offers new perspectives on food analysis, diet characterization, and gut microbial dynamics. Solid-state $^{13}C$ CPMAS NMR spectroscopy was first applied to Mediterranean plant litter to track chemical changes during decomposition and validated against the process-based OMDY model. The same approach was then extended to 38 whole foods, showing that intact matrices can be classified into meaningful groups by their chemical composition, providing a non-destructive alternative to conventional food categories. Ecological stoichiometry was introduced to dietary analysis using the carbon-to-nitrogen (C/N) ratio. Across 160 countries over five decades and ten popular diets, this metric revealed socioeconomic trends in food consumption and provided an ecological perspective beyond macronutrient-based assessments. Microbial community theory was examined by comparing generalized Lotka-Volterra (gLV) models with an existing model that incorporates self-inhibitory compounds. Finally, re-analysis of gut metagenomic datasets revealed that while dietary changes mainly affected the taxonomy of rare species, health status altered both richness and abundance distributions. Dominant taxa formed a resilient core, while rare species accounted for variability. Overall, this thesis highlights the scientific and pedagogical value of comparing ecosystems under a standard lens, demonstrating how multidisciplinary approaches can enrich our understanding of food systems, diets, and gut microbiota.

Downloads

Actions (login required)

Modifica documento