A Designer Antioxidant-Rich Tomato Soup As a Vehicle for Bioavailabilities of l-Tryptophan, Serotonin, and Melatonin: In Vitro Dissolution Study, In Vivo Rat Feeding, and iHOMA2 Predictive Modeling

To deliver a food vehicle of melatonin, serotonin, and l-tryptophan (MST), a minimally processed antioxidant-rich tomato soup was developed by using minimal food additives and minimal thermal processing conditions, preserving the natural antioxidant synergy. In vitro release of MST in simulated salivary and gut buffer(s) followed different kinetic models. In vivo bioavailabilities of MST could be unambiguously demonstrated through feeding trials in male Sprague–Dawley rats, wherein ∼25%, 40%, and 88% enhancement in levels of melatonin, serotonin, and l-tryptophan, respectively, occurred in their serum within 60 min of gavaging the soup. However, the natural trends of vacillation of serum concentrations of indoleamines remained unaltered. Non-invasive iHOMA2 predictive modeling proved that the soup metabolism indeed involved the functional centralities of the liver and the periphery, besides promoting glucose uptake in the brain. The findings of these investigations have the potential to inform this oil- and sugar-free soup to be a functional food delivering molecular nutrition in terms of MST.