**2.3 Black cumin (***Nigella sativa***) seed**

*Nigella sativa* (*N. sativa*, family Ranunculaceae), popularly known as black seed or black cumin or Kalonji in Hindi, is an annual herb with various pharmacological properties and a widely used medicinal herb across the world with a rich historical and religious background. *N. sativa* is native to Southern Europe, North Africa and Southwest Asia and it is grown in many countries around the world like the Middle Eastern Mediterranean region, South Europe, India, Pakistan, Syria, Turkey, Saudi Arabia [52, 53]. Black seeds and oil have been used in traditional medicine for more than 2000 years, and Hippocrates and Discroides termed it "the Melanthion" [54]. It is an important drug in various traditional system of medicine like Unani and Tibb, Ayurveda and Siddha. Traditionally, *N. sativa* has been used to treat a wide

#### *Traditional Islamic Herbal Medicine and Complementary Therapies DOI: http://dx.doi.org/10.5772/intechopen.101927*

range of illnesses, diseases, and conditions affecting the respiratory system, digestive tract, kidney and liver function, cardiovascular system, and immune system, as well as for overall well-being [55]. In Arabic, *Nigella* is known as 'Habbatul barakah', which means the seed of blessing. In Islam, It is considered as one of the most effective kinds of curing medicine available as it was stated in one of the Prophetic hadiths that black seed is the remedy for all illness except death. In Tibb-e-Nabwi (Prophetic Medicine), it is suggested to use it on a regular basis [56]. Black seeds have quite a rich history of folkloric use as food and medicine in Indian, Arabian, Southeast Asian, and Middle Eastern civilizations, and have traditionally been used to cure asthma, bronchitis, rheumatism, and other inflammatory illnesses. Extract prepared from black seed is used for the treatment of indigestion, diarrhea, loss of appetite, amenorrhoea, dropsy, and dysmenorrhoea and useful in the cure of skin eruptions and worms [57].

Various therapeutic attributes of black seed and its active component thymoquinone have been shown in *in vitro* and *in vivo* investigations, including anti-cancer [58], anti-microbial [58], anti-pyretic, contraceptive and anti-fertility, anti-oxytocic [52], antitussive, anti-inflammatory [59], and antioxidant properties [60]. Black seed has been shown to have anticancer action in blood, breast, colon, pancreatic, liver, lung, fibrosarcoma, prostate, and cervical cancer cell lines, as well as in animal models of lung, kidney, skin, colon, and breast cancer [61]. Phytochemical investigation of *N. sativa* revealed the presence of hundreds of phytoconstituents, mostly alkaloids, saponins, sterols, and essential oil.

The most important active compounds are thymoquinone (30–48%), thymohydroquinone, dithymoquinone, p-cymene (7–15%), carvacrol (6–12%), 4-terpineol (2–7%), t-anethol (1–4%), sesquiterpene longifolene (1–8%) α-pinene and thymol [62]. Among the various active components reported thus far, thymoquinone, which is a major component of essential oil, is the most bioactive chemical and has a variety of therapeutic properties (**Figure 3**).
