Ethanol extracts from twelve Curcuma species rhizomes in China: Antimicrobial, antioxidative and anti-inflammatory activities

Abstract Curcuma species as elements in traditional Chinese medicines play important roles in anti-inflammatory, antimicrobial, antirheumatic and antiviral activities. The bioactivities of ethanol extracts of 12 Curcuma species rhizomes were explored in this study. Most of these ethanol extracts showed excellent antioxidant activities, and the C. sichuanensis extracts (0.66 μM TE/mg EE) exhibited the best activities. These extracts not only had good antimicrobial activity against gram-negative bacteria (C. kwangsiensis var. nanlingensis, MIC=275.65 μg/ml), gram-positive bacteria (C. phaeocaulis, MIC=285. 52 μg/ml) and fungus (C. longa, MIC=80.87 μg/ml), but also revealed anti-inflammatory activities (C. aromatica, 42.6% inhibition at 100 mg/kg) suppressing the expression of TPA-stimulated inflammatory cytokines, COX-2 and TNF-α. Consequently, some Curcuma species can be used as natural antioxidants, antimicrobial or anti-inflammatory agents in functional foods, pharmaceuticals and cosmetics.