Phytochemical Study and Evaluation of the Antioxidant Activity of <i>Cymbopogon citratus</i> by Different Tests (<i>TAC</i>, <i>DPPH</i>,<i> ABTS</i>)

Cymbopogon citratus is widely recognized for its many virtues, particularly in the fields of nutrition and health. It is frequently used in infusions, decoctions and essential oils, as well as for its antioxidant properties. The main aim of this study was to determine the chemical composition of Cymbopogon citratus extracts, as well as their antioxidant potential, both in terms of aqueous extracts and essential oil. To do this, C. citratus leaves were dried at room temperature, then pulverized using a grinder. The powder obtained was used to prepare three types of aqueous extracts in the form of: macerate, infused and decocted in a ratio of 10 g powdered sample to 100 ml water with an extraction yield of: (12.2%); (11.63%) and (9.25%) respectively. Physicochemical analysis using photo-colorimetric techniques, including Folin-Ciocalteu and aluminum chloride methods, allowed to know the phytochemistry of the various C. citratus aqueous extracts prepared, with the marked presence of several bioactive compounds such: alkaloids, flavonoids, tannins, coumarins, saponosides, leucocyanines, sterols and triterpenes, carotenoids, fixed oils and fats and the absence of anthraquinones, anthocyanins, gums and mucilages and emodins. Total polyphenols, measured in gallic acid equivalents (mg EAG/100 of RP), showed a higher level of content in the infused (822.17) followed by the macerate (481.59). Flavonoids and tannins in milligrams of catechin equivalents (mg EC/100g of RP) are high in the infused and with: (283.04) and (235.83) respectively. However, tannins in mg EC/100g of RP in the macerate are high with (3.28) and (3.24) in the decoction. The DPPH (Diphenylpicrylhydrazyl), ABTS (2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) and TAC (Total Antioxidant Capacity) methods showed that the extract richest in polyphenols showed the highest antioxidant activity.