Antioxidant activity, total phenolic and flavonoid contents of selected medicinal plants used for liver diseases and its classification with chemometrics

Liver disease has become one of the major health problems in the world, and the death rate is going rapidly toincrease. Oxidative stress plays a crucial role in the emerging, development, and the progression of liver diseases.Ethnobotanical research has an undoubted profound impact on the development of numerous new drugs. The aimof this research, therefore, was to examine the antioxidant activities of 14 selected plants used for treating liverdiseases by traditional healers of Indonesia ethnicities and to classify these plants using chemometrics of principalcomponent analysis (PCA). The extraction using methanol as the solvent was performed with two stages maceration.Total phenolic and flavonoid compounds were determined by Folin–Ciocalteau and AlCl3 method, respectively,whereas antioxidant activity was estimated using 2,2′-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging,trolox equivalent antioxidant capacity (TEAC), and ferric reducing antioxidant power (FRAP) assay. Among 19methanol extracts of 14 plants, the leaves of Baccaurea racemosa, Macaranga subpeltata, and Piper sp. showed thehighest antioxidant properties. The phenolic content correlated with TEAC, FRAP, and DPPH radical scavengingactivity, while flavonoid did not significantly affect these antioxidant activity methods. PCA successfully classifiedthe plant samples using the variables of antioxidant activities and phenolic-flavonoid contents. The selected plantshave promising antioxidant properties which support their utilization for either liver diseases medication or oxidativestress-related diseases prevention