Deep eutectic solvents as a new type of eco-friendly solvents have attracted attention in chemistry, medicine, and other fields for the extraction and separation of target compounds from medicinal plants. Deep eutectic solvents are easy to prepare and have many advantages as solvents, such as chemical inertness with water, low cost, easy biodegradability, and pharmaceutically acceptable toxicity. In this study, a deep eutectic solvent made up of choline chloride-glycerol (1:2) was used for the extraction of flavonoids from Catharanthus roseus plant parts (flower petal, leaves, stem, and root). The highest amount of phenolic content was detected in flower petal, that is, 194.50 mg GAE/g. In DPPH test, the maximum amount of antioxidant activity determined in the flower petal was 73.13%; IC 50 was calculated by using a linear regression equation; IC 50 value of the standard, stem, root, leaf, and flower petal was 13.22, 90.44, 83.93, 120.14, 79.49 μg/ml, respectively. The result of this research is that Catharanthus roseus has a compatible antioxidant activity. This can be helpful for the treatment of diseases caused by free-radical oxidative stress.

Green technology is the most important topic in the pharmaceutical field because it reduces the cost of medicines and minimizes the environmental impact of the field and is better for human health and safety. Green chemistry emphasizes that the solvent should be nontoxic, safe, cheap, green, readily available, recyclable, and biodegradable. Deep eutectic solvents, a new type of green solvent, have some renowned properties-for instance, high thermal stability, low vapor pressure, low cost, biodegradability, and high viscosity. In this study, deep eutectic solvents made up of choline chloride-glycerol (1:2) were used for the extraction and isolation of flavonoid (rutin, gallic acid, and quercetin) from Catharanthus roseus plant parts, flower petal, leaves, stem, and root. The amounts of rutin and quercetin in flower petal are 29.46 and 6.51%, respectively, whereas, rutin, gallic acid, and quercetin amounts in leaves are 25.16, 8.57, and 10.47%, respectively. In stem the amounts of rutin, gallic acid, and quercetin are 13.02, 5.89, and 7.47%, respectively. In root, only quercetin has been obtained that is 13.49%. The HPLC is an analytical method, which was found to be an excellent technique for determination of rutin, gallic acid, and quercetin using deep eutectic solvent extraction from plant parts of Catharanthus roseus.

Green technology is the most important topic in the pharmaceutical field because it reduces the cost of medicines and minimizes the environmental impact of the field and is better for human health and safety. Green chemistry emphasizes that the solvent should be nontoxic, safe, cheap, green, readily available, recyclable, and biodegradable. Deep eutectic solvents, a new type of green solvent, have some renowned properties—for instance, high thermal stability, low vapor pressure, low cost, biodegradability, and high viscosity. In this study, deep eutectic solvents made up of choline chloride-glycerol (1:2) were used for the extraction and isolation of flavonoid (rutin, gallic acid, and quercetin) from Catharanthus roseus plant parts, flower petal, leaves, stem, and root. The amounts of rutin and quercetin in flower petal are 29.46 and 6.51%, respectively, whereas, rutin, gallic acid, and quercetin amounts in leaves are 25.16, 8.57, and 10.47%, respectively. In stem the amounts of rutin, gallic acid, and quercetin are 13.02, 5.89, and 7.47%, respectively. In root, only quercetin has been obtained that is 13.49%. The HPLC is an analytical method, which was found to be an excellent technique for determination of rutin, gallic acid, and quercetin using deep eutectic solvent extraction from plant parts of Catharanthus roseus.