Planta Med 2009; 75 - PI24
DOI: 10.1055/s-0029-1234788

Free radical scavenging and antityrosinase activities of guava leaf extract

N Kamkaen 1, 2, C Managit 1, S Weerataweeporn 1, S Chuanoi 1, S Pitiporn 3
  • 1Faculty of Pharmacy, Srinakharinwirot University, Nakhon Nayok, 26120, Thailand
  • 2Institute of Research and Development, Suan Dusit Rajabhat University, Bangkok 10330, Thailand
  • 3Pharmacy Department, Chophaya Abhaibhubejhr Hospital, Prachinburi 25000, Thailand

The aim of this study was to evaluate free radical scavenging and antityrosinase activities of the ethanolic extract of guava leaf (Psidium guajava Linn.). Anti-free radical and antityrosinase activities were used as the outcome of the antioxidant and whitening properties. The percentage of free radical inhibition was evaluated by DPPH assay compared to the standard gallic acid. The percentage of tyrosinase inhibition was examined by Dopachrome method compared to the standard arbutin. The results of free radical scavenging activity of the guava leaf extract was found to be IC50=53.19µg/ml compared with gallic acid (IC50=5.21µg/ml). The antityrosinase activity was shown to be IC50=9.86mg/ml compared with arbutin (IC50=7.3mg/ml). Gallic acid, one of the phenolic compounds in the ethanolic extract of guava leaf, was measured by HPLC technique to be 3.07µg/ml. The guava leaf may be a potential source of natural antioxidant and whitening agents which could be incorporated into a range of cosmetics and health products [1–3].

Acknowledgements: Thailand Research Fund (TRF) through Industrial and Research Projects for Undergraduate Studies (IRPUS) 2550, Chophaya Abhaibhubejhr Hospital Foundation.

References: [1] Tachakittirungrod, S. et al. (2007) Food Chem. 103:381–388.

[2] Lim, Y.Y. et al. (2007) Food Chem. 103:1003–1008.

[3] Yan, L.Y. et al. (2006) Sunway Acad. J. 3:9–20.