CHEMICAL COMPOSITION AND ANTIMICROBIAL ACTIVITY OF THE CURCUMA LONGA L.SENESCENT LEAVES.
Keywords:
Turmeric, Essential oil, AntimicrobialAbstract
Curcuma longa L. (turmeric) leaf is a residual product during root harvesting operations. Traditionally, these leaves, are widely used in cooking, are aromatic and contain essential oil. The Brazilian production of turmeric is concentrated in the states of Goiás, Minas Gerais and São Paulo. The objective of this study was to determine the chemical composition of the senescent leaves of a germplasm bank containing 36 access in São Paulo, in order to select the best plants and to evaluate the antimicrobial activity of the essential oils obtained from their senescent leaves. The essential oil content varied from 0.27 to 1.01% and 17 substances were identified, which represented 97% of the identified compounds. Of this total, the main compounds found in the essential oil were the monoterpenes (91 to 94.5%). The α-felandrene was the major compound (ranging from 20.7% to 31.1%), followed by p- cymene (19.2% to 30.8%), terpinolene (12.8% to 20.1% ), 1,8-cineole (8.1% and 13.2%), limonene (4.2% to 5.2%), β-pinene (2.4% and 4.8%), myrcene 2.4% to 3.4%), β-pinene (1.6% to 3.1%) and d-3-carene (1.2% to 1.6%). The germplasm bank can be grouped into three distinct groups according to the chemical characteristics of the senescent leaves, each group 1,2 and 3 being represented randomly by the respective access 22, 30 and 10. The antimicrobial properties of the essential oil showed MIC 2 mg / mL for Enterococcus hirae, Escherichia coli and Staphylococcusaureus.