Total Phenolics, Total Flavonoids and Antioxidant Activity of Different Ethanolic Aqueous Extracts Of Gynura Procumbens (Lour.) Merr.

Author

Kuong Y.M., Khaled A., Vlkneswaran M., Sadikun A and Zaini M.
School of Pharmaceutical Sciences, Universiti Sains Malaysia, 11800 Minden, Penang
Tel: +604-6533888 ext. 4711 E-mail: yowmeng2002©yahoo.com

Language

English

Title

Total Phenolics, Total Flavonoids and Antioxidant Activity of Different Ethanolic Aqueous Extracts Of Gynura Procumbens (Lour.) Merr.

Proceeding

Medicinal and Aromatic Plants Seminar (MAPS 2010)

Date

3rd August - 4th August (2010)

Place Held

Forest Research Institute Malaysia(FRIM)

Abstract

Gynura procumben (Lour.) Merr. (Compositae), locally known as ‘Sambung nyawa’, is a weakly climbing herb and was traditionally used to treat diabetes, kidney problems, inflammation and rheumatism. In the present study, total phenolics, total flavonoids and antioxidant activity were carried out on four aqueous ethanol extracts (95, 75, 50, and 25% vlv) and 100% water extract by maceration. The same study was also carried out on three 95% ethanol extracts obtained from different extraction methods, namely, soxhlet, maceration and ultrasonication. The total phenolics content was determined using the Folin-Ciocalteu reagent method, and the total flavonoids was determined using the aluminium chloride solution method. The free radical scavenging activity was examined using the (1,1-diphenyl-2-picrylhydrazyl) DPPH solution method. Each 95% ethanol extract obtained from maceration, ultrasonication and soxhiet extraction contained 50.63±0.32, 49.57±0.31 and 35.14±0.77 mg/ml gallic acid equivalent, respectively. Thus, this showed that maceration and ultrasonication gave equivalently higher phenolic content as compared to soxhlet extraction. While total flavonoids from the 95% ethanol extracts of maceration, ultrasonication and soxhiet were 24.52±0.14, 23.22±0.57 and 23.44±0.52 mg/ml quercetin equivalent, respectively. The free radical scavenging activity studies on 0.25 mg/mI of the above same extracts, that from maceration showed the highest inhibition (61.02±0.81%) followed by ultrasonication (44.23±1.74%) and soxhlet (28.32±1.20%). For maceration extracts from different ethanol/water ratio, 50% aqueous ethanol extract contained the highest amount of phenolic compounds (76.20±0.6 mg/mI gallic acid equivalent), while 75% aqueous ethanol extract contained the highest flavonoid content (26.16 ±0.60 mg/mI quercetin equivalent). However, 75, 50 and 25% aqueous ethanol extract showed good free radical scavenging activity with inhibition percentage of 77.84±1.04, 75.30±0.04 and 68.82±1.92%. The water extract showed lower activity with of 35.35±1.47% at the concentration of 0.25 mg/ml. In conclusion, different extraction methods and solvent systems used for extraction could influence the total phenolics and flavonoid content as well as the antioxidant property of G. procumbens extracts.

Keywords

Gynura procumbens; total phenolics; total flavonoids; antioxidant

Session

Poster Abstracts: P28

Topic

Harnessing the Tropical heritage: Recent Advances in R&D and commercialization