Valorization of Garlic Peel ( <i>Allium sativum L.</i> ): A Comprehensive Review of Its Nutritional, Phytochemical, and Therapeutic Potential

Abstract Garlic (Allium sativum) was one of the earliest plants to be grown. It has been used for a long time as a food, condiments, cuisine and traditional medicine. Garlic has the potential to affect numerous cardiovascular factors. The organic compounds called allyl sulfurs in garlic also have been shown to have strong anti-cancer effects. Because garlic peel was regarded as an agricultural waste, it was usually discarded or burned as waste, although it makes up 25% of the total garlic production. The primary aim of the present review is to provide critical evaluation of the nutritional composition of garlic peel, phytochemical analysis of garlic peel, bioactive constituents of garlic skin and ethnomedical importance of garlic skin with hepatoprotective, anti-bacterial, anti-apoptotic, antioxidant, anti-inflammatory and ulcerative colitis management activity. In addition, this review identifies the main waste streams of the industrial processing of garlic and critically assesses valorization of garlic skins as a target. It provides detailed information on the use of specific compounds extracted from the peels, more specifically structural polysaccharides and phenolic acids, as sustainable raw materials for industrial applications, such as biopolymers, natural food preservatives and biosorbents, in order to contribute to a circular economy.