Abstract

Sumac (Rhus coriaria) is a flowering plant that is widely consumed for its promoting health benefits and used in food preparations as a spice in the Mediterranean region. It is a high shrub or small tree with imparipinnate leaves, villus and red fruits with one-seeded drupe, and small greenish-white flowers. The nutraceutical and pharmaceutical potential of sumac makes it a remarkable functional food. In this review, the phytochemical and nutritional properties of sumac as an under valorized functional food have been discussed. Flavonoids, anthocyanins, phenolic acids, and organic acids have been reported as dominant phytochemicals in sumac, which are well known for their pharmacological properties that attract many consumers to commonly choose sumac in their diet as well as food preparations. The remarkable volatile compounds present in sumac give it a unique aroma that increases its acceptance by consumers and potential use in the food industry. Sumac has been evaluated for a broad range of nutritional and pharmacological activities such as antioxidant, antinociceptive, anti-inflammatory, anti-diabetic, hepatoprotective, cardioprotective, anticancer, anti-infertility, and neuroprotective potential. This review has also briefly outlined the safety concerns concerning the use of sumac in terms of toxicology and interactions.

Introduction

Today, humanity and especially most communities in developing countries depend on medicinal plants as a valuable heritage for their primary health care and substances. Functional foods (FFs) are those foods that may promote health benefits beyond their supply of essential nutrients. Owing to its basic nutritional and nutraceutical properties, a functional food can decrease the risk of the onset of many chronic diseases, and can contribute to health[[1], [2]]. FFs can be considered as whole, fortified, enriched or enhanced foods that provide health benefits beyond the provision of essential nutrients (e.g., vitamins and minerals) when they are consumed at efficacious levels as part of a varied diet regularly[3]. Rhus coriaria, also called sumac, is a high shrub or small tree (1–۳ m high) with imparipinnate leaves, villus, and red fruits with one-seeded drupe, and small greenish-white flowers organized in panicles[[4], [5]]. Given its nutritional value and its phytochemical components (flavonoids, flavones, anthocyanins, tannins, organic acids, fibre, proteins, volatile oils, nitrites, and nitrates), it has been used both as a spice and gives a sour lemon taste to various foods such as vegetables, meat dishes and rice then as a medicinal herb. It contains natural pigments such as anthocyanins and is used as coloring agents in food industry[[6], [7]]. Research efforts on sumac extracts to date indicate a promising potential of the species of this genus to provide bioproducts that have desirable biological activities: antifungal, anti-inflammatory, antimalarial, antimicrobial, antitumorigenic, antioxidant, antiviral, hypoglycaemic, anti-inflammatory, antimalarial, antimicrobial, antitumorigenic, antioxidant, and antiviral. In traditional medicine, this plant has been used in the treatment of many diseases such as cancer, stroke, diarrhoea, hypertension, dysentery, haematemesis, ophthalmia, stomach ache, diuresis, diabetes, atherosclerosis, measles, smallpox, aconuresis, teeth and gum ailments, headaches, animals bites, dermatitis and liver diseases[8]. Sumac may also have the potential for the prevention or treatment of atherosclerosis and its clinical manifestations. The target of this study was designed to evaluate sumac (R. coriaria) as an undervalorized functional food.

Conclusion

Due to the large variation in the bioactive and phytochemical content of sumac, sumac has a broad range of nutraceutical and pharmacological benefits. This makes sumac a rich functional food that can contribute to healthy living. In addition, the health promoting benefits associated with sumac can potentially increase its applications in different commercial products. More evidence and research are needed to explore the current nutritional benefits in humans through clinical trials. In fact, the more efforts could be applied to ensure that the phytochemical content of sumac is highly bioaccessible and bioavailable for more significant bioactivity. These efforts may be through encapsulating sumac and preparing different sumac formulations through complexation with other health promoting herbs or spices.