Isolation and identification of leaf flavonoids from commercial varieties of Psidium guajava L.

• Grant number: 06/04765-8
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: April 01, 2007
• End date: December 31, 2007
• Field of knowledge: Biological Sciences - Botany
• Principal Investigator: Cláudia Maria Furlan
• Grantee: Samantha Zanotta
• Host Institution: Instituto de Biociências (IB). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

The northeast of Brazil is the main region cultivating guava fruits, Psidium guajava L. (Myrtaceae), a tropical species used in natura or to produce jelly, ice-cream, juice, wine, and industrialized pulp. This region can be climatologically characterized as semiarid, demanding cautions with the water supply. Studies with guava foliar extracts showed some pharmacological effect as, for example, antioxidant, anti-malaria and anti-diarrhea. Those effects are correlated to the presence of phenolic compounds, in special to tannins and flavonoids, recognized as having the property of inhibiting oxidation reactions and scavenging of free radicals. This study aims to evaluate possible differences on foliar flavonoid composition and quantities of three commercial cultivars of Psidium guajava L., cv. Paluma’, cv. Pedro Sato and cv. Sassaoca when submitted to a water and a mechanical stress. In addition, the better knowledge about how some kinds of stress affect the biosynthesis of natural products with pharmacological properties can help to reinforce conclusions about plant cultivation conditions. (AU)