Peach (Prunus persica (L.) Batsch) seeds and kernels as potential plant-based functional food ingredients: A review of bioactive compounds and health-promoting activities

Prunus persica (L.) Batsch (or peach) (Rosaceae) is the most important stone fruit crop in many areas, including North Africa, South Africa, and Europe. Peaches are well known for their flavor, nutritional value, and potential health benefits. During the consumption of peach fruit, usually jams, jellies, juices, and other food products, the seed and kernel (stone) is disposed of as waste. However, the seeds and kernels of peach fruit are considered remarkably rich sources of sodium, potassium, zinc, copper, iron, fatty acids (linolenic, oleic, palmitic, and linoleic acids), fiber, and carbohydrate (sucrose, glucose, and fructose) content. The preliminary results of various studies demonstrated that seed and kernels of peach fruit contain high amount of protein and bioactive peptides. Seed and kernels extract showed anti-ageing, anti-biofilm properties, protection against oxidative stress, cancer cell proliferation, inhibit type II diabetes, Alzheimer's disease and obesity. It was concluded that biological properties are stimulated by the presence of hydroxycinnamic acids, polymeric procyanidins, cyanogenic glycosides, carotenoids and other metabolites. Oil extracted from the seeds of peach extracted via, supercritical CO2 shows the presence of phytosterols (stigmasterol, & beta;-sitosterol, campesterol) that were widely known for their cholesterol-lowering effects, while additional research showed peach kernels as a potent source of phenolic compounds with high concentration of phenolic acids and catechin. Amygdalin is present in the seed extract of peach fruit, that changes into cyanide and supposed to kill cancer cells. A variety of studies are being conducted to recover possible bioactive compounds from peach seed and/or kernels in order to prevent envi-ronmental pollution and also economic losses. Thus, peach wastes, by-products, and their valorized compounds can be used as a sustainable resource of various important compounds that can be of great importance in different functional foods, pharmaceuticals, animal feed industry and cosmetics.