ournal of Chemistry
Volume 2019, Article ID 2793058, 12 pages

Abstract
The objective of this work was to determine the main antioxidant aglycones of flavonoids
and tannins in antioxidant extracts from Melastoma dodecandrum Lour. (MD), based on
its extraction and purification process optimization and component identification by
UPLC-ESI-MS/MS.

2.2. Chemicals
The reference substances including p-coumaric acid, gallic acid, ellagic acid, apigenin,
naringenin, luteolin, kaempferol, quercetin, vitexin, and isovitexin were obtained from
Chengdu Alfa Biotechnology Co., Ltd. (Chengdu, China). Their purity was all greater than 98% (w/w).