Exploration of Phytochemical Constituents in Neoshirakia japonica by LC-MS and In Silico Evaluation of a New Antioxidant Targeting the NOX Family

Neoshirakia japonica, a small deciduous tree belonging to the family Euphorbiaceae, has traditionally been used to relieve pain and fatigue in ancient Asia. To date, there have been no attempts to investigate the overall metabolite profiles of N. japonica. To obtain the phytochemical profiles of its aerial part and root, the extracts were analyzed by UHPLC Orbitrap mass spectrometry, and the metabolites were clustered using feature-based molecular networking (FBMN). The common major constituents of the two different parts were annotated as ellagitannins and ellagic acid derivatives using the GNPS database and SIRIUS software, and a total of 20 compounds were isolated. With FBMN guidance, five minor ginsenosides (10–14) were isolated from the BuOH fraction of the aerial part and first identified in this plant. Also, one new xanthoxylin derivative (16) was discovered from the root, and its antioxidant activity and binding potential to NOX family proteins were evaluated by in silico studies. Consequently, this research aims to provide a comprehensive understanding of the major and minor components of N. japonica by part and suggests its potential as a drug candidate for antioxidant-related diseases.