Acta Pharm. 64 (2014) 369-378
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