Phytochemicals from Peanut (Arachis hypogaea L.) Skin Extract with Potential for Pharmacological Activity

Background: Plant phenolics, commonly present in legumes, leafy vegetables, fruits, grains are a key source of bioactive nutrients existing as flavonols, flavanones, flavanols, phytosterols, among others. Peanuts, being crops of high commercial use, undergo processing that generates voluminous agro-wastes. The waste comprises both the shells and skins, which could be valorized. Its versatile functionality has encouraged extensive research into peanut skin-derived chemicals for diverse applications over the past few decades. Peanut skin, however, is ascertained to be rich in flavonoids, stilbenes (resveratrol), and other phenolic compounds. Methods: This review presents the biologically active compounds and pharmacological activities of peanut skins and their related works over the past few years. Articles carefully chosen from broad databases such as Scopus, Science Direct, Pub Med, SciFinder, among others, were used as the primary data. Results: The bioactive components of peanut skin extracts exhibit anti-oxidant, anti-inflammatory, anti-bacterial, anti-viral, anti-fungal, anti-cancer/anti-tumour, anti-cardiovascular, and anti-diabetes/ obesity activities via in vitro and in vivo models. Besides, their varied biological properties make them potential precursors for the management of diverse diseases and ailments. Potential Applications: Phytochemicals from peanut skins could be deployed as antioxidant, antidiabetic and antimicrobial agents in drugs for the clinical treatment of ailments with extensive clinical applications. Conclusion: The present review covers the chemistry and pharmacological activities of peanut skin phytochemicals. Our findings in this review substantiate the importance of peanut skin extracts and their varied potential for the treatment of specific diseases. The results indicate that they are attractive target compounds for the development of new drugs. We hope that this information will inform further in vivo studies on the role of peanut skin phenolic compounds in our health.