CHARACTERIZATION AND QUANTIFICATION OF NORDIHYDROGUAYARETIC ACID OF THE ETHANOLIC EXTRACT OF Larrea divaricata CAV. by UHPLC-DAD-MS/MS

JOFRÉ MA; FAVIER L; CIANCHINO V; ORTIZ JE; FERESIN G; CIFUENTES D; ORTEGA C.

San Juan

Congreso; XLI Reunión Científica Anual de la Sociedad de Biología de Cuyo; 2023

Sociedad de Biologia de Cuyo

L. divaricata is a species used in popular medicine to treat of different affections, focusing on its use as an antimicrobial agent. The aim of this study was to characterize and quantify nordihydroguayaretic acid (NDGA) from the ethanolic extract of Larrea divaricata by UHPLCDAD-MS/MS.The aerial parts of L. divaricata Cav. were collected in February, 2015 in Nogolí, San Luis, Argentina. A voucher specimen was deposited at the Herbarium of the Universidad Nacional de San Luis (UNSL Del Vitto and Petenatti 8432). The vegetable materials were dried in shade at room temperature, then chopped and ground to fine powder in a mechanical blender. An ethanolic extract (EE) was prepared from the aerial parts of L. divaricata (300 g) following official methods described by FA VIIEd., (2003). The solid residue was evaporated under reduced pressure, and then dried in an oven (40 °C) to constant weight. (Ethanolic SR= 23.10 g/mL). Its physicochemical parameters were determined. The characterization of the L. divaricata EE was performed in an ACQUITY H–Class UPLC equipped with a XEVO TQS micro triple quadrupole mass spectrometer (Waters Corp, Milford, MA, USA) with electrospray ionization (ESI). The sample and standard solutions were filtered through a 0.22 µm nylon membrane prior to analysis. Each filtered sample (20 μL) was injected into the UHPLC system and separated on a UPLC ACQUITY BEH C18 column (1.7 μm, 2.1 mm × 50 mm) using an isocratic mixture of 0.1% Formic Acid: Methanol 40:60 as the mobile phase. The flow rate was 0.2 ml/min and the injected volume was 20 μl. The separation temperature was 38 °C (column temperature). The analysis was performed in ESI positive mode using daughter MS/MS function and a collision energy of 20eV. The total time for the analysis of each sample was 20 minutes. The properties of the EE were: relative density (2.50 g/cm3), pH (4.88), refractive index (1.395). While the concentration of NDGA calculated through the calibration curve equation was 12.92 ppm (r2=0.991879). The developed methodology proved to be selective, linear, precise, and accurate. This method would represent a fast alternative method for the quantification of NDGA and quality control of the species under study. Area. BIOQUIMICA, FISIOLOGIA, PATOLOGIA Y PRODUCCION VEGETAL N° 01