Dendrobium officinale leaves as a new antioxidant source

In this work, we found that the extract of leaves of a famous Traditional Chinese Medicine TiepiShihu (Dendrobium officinale Kimura et Migo) contained high content of flavonoids ranging from 7.66 mg.g(-1) to 9.50 mg.g(-1) dried weight and possed potent antioxidant activities. There was a strong positive correlation between DPPH radical scavenging rate and total flavonoids content. Furthermore, the antioxidant principles were determined by combination use of DPPH/ABTS(+)-HPLC assays and HPLC-DAD-based pattern recognition technologies. Their structure was further identified by on-line and off-line HPLC-ESI-MS/MS and following targeted isolation and NMR recognition. 14 phenolic herber-markers including quercetin-type flavonols and apigenin-type flavones were characterized from the leaves of D. officinale. The major flavonoid component of leaves was rutin and its content ranged from 1.33 to 2.89 mg.g(-1) dry weight. In summary, whole results indicated that the leaves of D. officinale might be developed as antioxidant sources for medicinal and health food resources. (C) 2017 Elsevier Ltd. All rights reserved.