Potent nitric oxide inhibitory sesquiterpenoids from the rhizome of Curcuma aromatica Salisb.

Abstract

One new sesquiterpenoid, curcaromatin (1), together with twenty-one known compounds 2–22, were isolated from the rhizomes of Curcuma aromatica Salisb. (Zingiberaceae). Their structures were established by extensive spectroscopic (1D and 2D NMR and HR-MS) analysis. Most of the isolated compounds were investigated for nitric oxide (NO) production in lipopolysaccharide (LPS)-activated RAW264.7 cells. (−)-Xanthorrhizol (3) displayed the strongest NO inhibitory activity with an IC₅₀ value of 4.3 μM, which was 3.7-fold more active than the reference compound, aminoguanidine (IC₅₀ 15.9 μM). The selectivity index (SI > 28.1) of compound 3 was almost 3-fold higher than that of aminoguanidine.

Graphical Abstract

Keywords:

• Curcuma aromatica
• Zingiberaceae
• sesquiterpenoids
• nitric oxide inhibitory activity
• anti-inflammation

Acknowledgements

W.P. thanks the scholarship from the Science Achievement Scholarship of Thailand, Ministry of Higher Education, Science, Research and Innovation. Partial supports from the Agricultural Research Development Agency (CRP6305030500) and the Center of Excellence for Innovation in Chemistry (PERCH-CIC), Ministry of Higher Education, Science, Research and Innovation are also gratefully acknowledged.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by The Thailand Research Fund (DBG6180030).