Durian (Durio zibethinus L.) fruit: A superior dietary source of natural glutathione and γ-glutamylcysteine

Numerous age -related degenerative diseases have been linked to diminished intracellular levels of glutathione (GSH), a vital antioxidant in the human body. Unfortunately, exogenous GSH encounters various barriers that prevent its entry into most human cells. gamma-Glutamylcysteine (gamma-EC), an immediate precursor of GSH, is a potential therapeutic agent that restores cellular GSH levels. Additionally, both compounds can serve as kokumi taste substances and enhance basic taste sensations. Considering the growing interest among health -conscious consumers toward naturally derived diets, the incorporation of fresh fruits and vegetables abundant in GSH and gamma-EC presents a promising alternative for supplementation. Screening of various plant samples, including fruits, vegetables, and mushrooms, revealed that ripe durian pulp exhibited the highest levels of GSH (similar to 2.6) and gamma-EC (similar to 14) per milligram per gram of dry weight. Owing to the popularity of durian-related products, we extended our investigation to analyze GSH and gamma-EC contents in processed products. Notably, durian chips and pastes displayed a significant decrease in GSH and gamma-EC levels, suggesting their sensitivity to heat. This observation was further validated by the observed instability of GSH and gamma-EC standards during heat treatment. Our findings underscore the potential of durian fruit as a rich dietary source of GSH and gamma-EC.