Antiinflammation constituents from Curcuma zedoaroides

Curcuma zedoaroides, a Zingiberaceae species, has been used for snake bite antidote and wound care in Thailand. Seven compounds were isolated from the bioactive chloroform extract consisted of one new guaiane sesquiterpene lactone, 5-epiphaeocaulisin A (4) and one new diarylheptanoid, 1,2,3,5-tetrahydroxy-1-(4-hydroxy-3-methoxyphenyl)-7-(4-hydroxyphenyl) heptane (7), together with five known guaiane-type sesquiterpene lactones including gweicurculactone (1), zedoalactone B (2), phaeocaulisin C (3), zedoalactone H (5), and zedoalactone E (6). The antiinflammation was investigated on NO and TNF-α production using RAW264.7 cells. In addition, the expressions of genes involved in inflammation including iNOS, COX-2, and TNF-α were assessed. The results found that Compounds 1-7 presented their antiinflammation against NO production. The most potential effects were demonstrated on Compounds 1 and 7 with IC₅₀ of 27.3 and 32.6 μM, respectively. Although, Compounds 1 and 7 did not inhibit TNF-α production, their suppression on iNOS and COX-2 mRNA expression were revealed. These results support the ability of chloroform fraction, Compounds 1 and 7 on antiinflammation, whereas others exhibited moderate and mild effect.