Nigella sativa: miraculous plant

Plants can be considered as factories producing various chemical compounds. Many of them are used to prevent diseases, and some of them are used as medicine or food [1]. Herbal medicines have long been used for different diseases [2]. Recently, the production of new products from natural plant sources has been considered. It is estimated that there are 300000 plant species in the world, of which only 15% have been studied in terms of medicinal potential [3]. One of the most valuable medicinal plants is Nigella Sativa, which are small seeds rich in many nutrients [4]. Nigella sativa from the Ranunculaceae family is an annual plant that grows in the Mediterranean region and widely in India, Turkey, Pakistan, and southern Europe [Figure 1] [5].

Figure 1: Nigella sativa

For more than thousands of years, this herb has been applied in various parts of the world as a preservative of food, spices, medicine, and treatment of many diseases in traditional medicine [6]. This seed has various names in different areas in the world. In Iran, it is called Shonaiz. In Europe, it is known as Ajenue, black cumin in America, Al-Sawda, Al-habbah, Kamounaswad, and Habbet el-Baraka in Arabic countries, Kalongi in India and Pakistan, and Schwarz kummel in Germany [7]. In describing the antiquity of using this plan, it can be said that Prophet Mohammad mentioned that "this plant is the cure for every disease except death." Besides, Avicenna, in his book "The Canon of Medicine" has mentioned the effects of Nigella Sativa on the improvement of fatigue and depression and increasing energy
levels [8, 9].

 The seeds of this plant are rich in various chemical compounds, including proteins, fixed and volatile oils, carbohydrates, and amino acids. Many studies have reported different bioactive compounds of Nigella sativa seeds [Table 1] [10]. One of the most important of them is thymoquinone [11]. Thymoquinone has different medicinal properties such as anti-viral, anti-inflammatory, anti-tumor, and anti-oxidation [12-14]. Also, Khalil et al., in their review, discussed the effect of thymoquinone
in reducing the risk of some chronic issues such
as neuropathy, nephropathy, retinopathy, cardiovascular diseases, diabetes, cancer, and obesity[15].

Table 1. Bioactive compounds from Nigella sativa seeds

Therapeutic and Pharmacological Activities of Nigella sativa

Extensive studies on Nigella sativa have been conducted over the past few decades. The results show that it has some medicinal properties and therapeutic activities. Hadi et al.'s study showed that consumption of Nigella sativa oil in patients with type 2 diabetes can improve oxidative stress [16]. Kanter et al., in an animal study, have found that Nigella sativa has antioxidant properties and increases the levels of antioxidant enzymes such as catalase and superoxide dismutase [17]. Another animal study illustrated that this herb has anti-inflammatory effects and can improve asthma [18]. According to Heshmati et al.'s meta-analysis, Nigella sativa could improve lipid profile and glycemic status in diabetic models [19]. Moreover, Khurshid et al. demonstrated the antiproliferative and apoptosis effects of Nigella sativa seed proteins [20]. Razmpoosh et al. showed that Nigella sativa supplementation improves kidney and liver parameters in obese women and reduces their risk factors for cardiovascular disease [21, 22]. Besides, Gilani et al., in a review, reported Nigella sativa biological activities such as antispasmodics, antihypertensive, antimicrobial, spasmolytic, analgesic, and bronchodilator[23].

Currently, Nigella sativa is one of the most sought after topics in the world. According to the results of studies, its seeds have many nutritional and medicinal values, and its rational consumption can improve and cure some diseases. However, further studies are needed to find its new biological activities, and more clinical trials are suggested to prove its medicinal properties.

Acknowledgments

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Authors’ contributions

All authors contributed to this project and article equally. All authors read and approved the final version of the manuscript.

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Conflict of Interest

The authors declare that there is no potential conflict of interests in this review.