Thesis On Antioxidant Activity Of Plants
3. Antioxidant Activity of the Selected Plants
(Turmeric): , a perennial herb, is a member of the Zingiberaceae family. The roots form an important ingredient of Chinese and Ayurvedic systems of medicine. The rhizomes of possess a large inventory of moniterpenoids, sesquiterpenoids and curcuminoids (; ), which show antibacterial, anti-inflammatory as well as antineoplastic activities. Curcuminoids, which are basically bioflavonoid compounds, exhibit a variety of beneficial therapeutic and preventive health effects (). Curcumin is the principal curcuminoid along with desmethoxycurcumin and bis-desmethoxycurcumin, the other two curcuminoids (). Insecticidal activity of the turmeric rhizome has also been reported (, ). Curcumin has antioxidant, anti-inflammatory, antiviral and antifungal actions (). Curcumin blocks NF-κB and the motogenic response in infected epithelial cells and carries thremendous therapeutic potential. It acts as an inhibitor for cyclooxygenase, 5-lipoxygenase and glutathione S-transferase. In addition to this, turmeric has been found to reduce the release of inflammation-inducing histamine, increase and prolongs the action of cortisol and improves circulation; thus increases the flushing toxins out of the body. Curcumin facilitates proliferation of CD4+ T-helper and B type immune cells.
Phd Thesis On Antimicrobial Activity Of Medicinal Plants
Oxidative stress and altered immune function: The correlation between and immune function of the body is beyond doubts. The skilled phagocytic cells (macrophages, neutrophils, eosinophils) possess an enzyme, the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (; ); which is responsible for the production of ROS following an immune challenge. The host defense mechanism uses the lethal effects of ROS and RNS in the killing pathogens. At the commencement of an , phagocytes increase their oxygen demand by 10-20 folds via., process of respiratory burst. The nascent oxygen generated by this enzyme serves as the starting material for the production of an array of reactive species. Production of other powerful pro-oxidants, such as (H2O2), hypochlorous acid (HOCl), peroxynitrite (ONOO¯) and possibly hydroxyl (OH●) and ozone (O3) by these cells have also been reported. Although, these highly reactive endogenous metabolites damage all the the bacterial cells non-specifically, they can also injure the host tissues (). Cashewnut, () is an antioxidant and is used in indigenous system for immunomodulation purposes (; ; , ).