TITLE:
Antioxidant, Antibacterial and Antitumor Activity of Ethanolic Extract of the Psidium guajava Leaves
AUTHORS:
Tatiane Vieira Braga, Rosana Gonçalves Rodrigues das Dores, Camila Soncin Ramos, Fernanda Cristina Gontijo Evangelista, Letícia Márcia da Silva Tinoco, Fernando de Pilla Varotti, Maria das Graças Carvalho, Adriano de Paula Sabino
KEYWORDS:
Guava, Antitumor, Medicinal Plants, Functional Foods
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.5 No.23,
November
27,
2014
ABSTRACT: Psidium guajava L. has extensive use in folk medicine. The aim of this study was to quantify the levels of phenolic, flavonoids, antioxidant activity, leathality assay and antibacterial and antitumoral activities of the extract of P. guajava. In the dry guava extract there were high levels of phenolics (766.08 ± 14.52 mg/g), flavonoids (118.90 ± 5.47 mg/g) and antioxidant activity (87.65%). The LD50 was 185.15 μg/ml. The MIC value was 250 μg/ml for Streptococcus mutans, Streptococcus mitis and Streptococcus oralis. IC50 of the extract tested in the HeLa, RKO and Wi cell lines was 15.6 ± 0.8 μg/ml, 21.2 ± 1.1 μg/ml and 68.9 ± 1.5 μg/ml, respectively. The results of all analyses allow us to conclude that the dry extract of guava leaves has promising activity to be applied topically in the oral cavity or in the development of antitumor formulation or even be used as a functional food.