Acta Pharm. 64 (2014) 369-378

 

full paper

Original research paper

 

Evaluation of the antioxidant activity of Coreopsis tinctoria Nuff. and optimisation of isolation by response surface methodology

SHUMIN LAN, JINGMING LIN and NI ZHENG

zhengni8787@163.com

1 Department of Pharmacy, Guangdong No.2 Provincial People’s Hospital, Guangzhou 510317, PR China

2 Department of Pharmacy, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, PR China

Accepted May 12, 2014

 

The aim of the present study was to determine the antioxidant activity of Coreopsis tinctoria flowering tops (CTFT). Studies were conducted to obtain suitable extraction conditions for chlorogenic acid, quercetin, luteolin, apigenin and kaempferol, which were identified and quantified by HPLC. Response surface methodology was employed to optimise the ultrasound-assisted extraction conditions, including extraction time, ethanol concentration and liquid-solid ratio. The antioxidant activity of the extracts was analysed using various antioxidant models, such as DPPH, ABTS and hydroxyl radical scavenging assay. CTFT extracted for 15.0 min with ethanol at a concentration of 60.4 % and with liquid-solid ratio 27.5:1 possessed a considerable amounts of total flavonoids and polyphenols (18.9 %). This extract showed higher scavenging activity of ABTS and hydroxyl radical activity than rutin, however not in the DPPH test. We may assume that CTFT possess antioxidant and free radical scavenging potentials.

 

Keywords: Coreopsis tinctoria (Asteraceae), flavonoids, polyphenols, antioxidant activity, response surface methodology, HPLC