**3.1 Phytochemistry**

Turmeric powder contains 69.4% carbohydrates, 6.3% protein, 5.1% fat and 3.5% minerals. The yellow color is due to the presence of curcumin (3–4%), which consists of curcumin I (94%), curcumin II (6%) and curcumin III (0.3%) (**Figure 4**) [27]. Curcumin derivatives such as dimethoxy and bis-dimethoxy have also been isolated from turmeric. Several substances occur in the rhizomes, including tumerone a,

**Figure 3.** *Turmeric.* *Vegetable and Herbal Extracts: A Way towards Preventive and Therapeutics Regimen DOI: http://dx.doi.org/10.5772/intechopen.101104*

**Figure 4.** *Curcumin derivatives.*

tumerone b, curzerenone, curdione, monoethoxycurcumin, and diethoxycurcumin. Its essential oils are derived from its leaves [28].

Turmeric has been reported to contain multiple chemical compounds such as linalool, caryophyllene, geraniol, sabinene, myrcene, and α-phellandrene.

#### **3.2 Medicinal and nutritional value**

Although turmeric has been around for thousands of years, it has recently become popular due to its medicinal properties. Traditionally, turmeric was used for its digestive and carminative properties [29]. Free radicals generated by oxygen can be scavenged by curcumin. In terms of antioxidant activity, it is comparable to vitamins C and E [30]. It prevents oxidative damage to lipids and hemoglobin. Macrophages that are activated by it are significantly less likely to produce reactive oxygen species such as H2O2, superoxide ions, and nitrite radicals [31]. Antioxidant properties are also present in its derivatives, bisdemethoxycurcumin and demethoxycurcumin. Researchers have shown that curcumin pre-treatment decreases the oxidative stress and improves ischemic conditions [32]. In an in vitro study, curcumin was found to enhance cellular resistance to oxidative stress in response to an inducible stress protein [33]. Researchers have found that turmeric can treat a number of diseases, and it can also prevent certain forms of cancer [34]. Skin cancers and precancerous conditions can also be treated with turmeric [34]. Turmeric is antispasmodic and can reduce digestive cramps, menstrual cramps and pains caused by osteoarthritis due to its ability to reduce pain and disability [35]. Curcumin shows strong potential for scavenging free radicals such as superoxide radicals, hydrogen peroxide and nitric oxide [36]. It reduces iron complex and inhibit lipid peroxidation [37].

Turmeric contains curcumin, a powerful anti-inflammatory ingredient that works by inhibiting inflammatory molecules in the body [35]. Researchers have shown that curcumin is beneficial to people suffering from conditions, including rheumatoid arthritis, inflammatory bowel disease. Several studies have suggested applicability of curcumin against cancer of many organs [38]. It induces apoptosis, inhibit progression of cell cycle and prevent growth of cancer cells [39]. curcumin induces apoptosis in different cell types such as human bladder cancer cells and arrests cancer cells [40]. It takes part in various signaling pathways and inhibit signaling through NF-қB which regulates expression of many genes responsible for malignancy [41]. Owing to its anti-inflammatory and anti-oxidant property it was also used against Alzheimer's disease [42]. It is also known to have metal chelating properties thus may reduce amyloid aggregation and reduce oxidative neurotoxicity [43]. Curcumin can be a future drug for the therapy of various neurological disorders especially depression and diabetic neuropathy [44].
