LARREA AMEGHINOI SPEG. (ZYGOPHYLLACEAE) “JARILLA RASTRERA”: ANTIOXIDANT, ANTIMICROBIAL AND CHEMICAL STUDIES

BRESSAN, M. E.; SEDE, S. M.; ARIZA, M. B.; SIMIRGIOTIS, M. J.; TAPIA, A.; LIMA, B.; GOMEZ, J.

San Juan

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

Sociedad de Biología de Cuyo

Larrea ameghinoi is a shrub endemic to Argentina that lives from Neuquén to Chubut. Its bark and leaves are popularly used to treat various ailments such as fever, back pain, as an emmenagogue, stimulating and promoting menstrual flow. In addition, it calms rheumatic pain due to its application in the form of a poultice. To date, the biological activities and chemical characterization of this species have not been reported. L. ameghinoi was collected in two different points from the province of Rio Negro, “Maquinchao” (MAQ) and a town near “Las Grutas” (SAO). The ethanolic extract was prepared from dried and ground plant material, and its antioxidant activities were evaluated using a panel of standardized tests what includes: DPPH radical trapping activity, Trolox equivalent antioxidant activity (TEAC) and Reducing power test (FRAP)) and its antimicrobial potential according to the Clinical and Laboratory Standards Institute (CLSI). SAO and MAQ showed strong DPPH scavenging activity (IC50 = 10 and 14 µg/mL, respectively), as 11 3 in the TEAC and FRAP assays. Regarding antimicrobial activity, SAO showed activity against Gram + bacteria, with MIC=125 μg/mL, while the MIC values were found against yeasts of clinical incidence (Candida albicans, C. parapsilosis, and C. tropicalis) between 125 to 500 µg/mL. The MAQ sample inhibited with values between 250 to 500 µg/mL the strains evaluated. In addition, both extracts showed a high content of phenolic compounds, 239.5 mg GAE/g and 215.6 GAE/g for SAO and MAQ samples, while that SAO exhibited higher values of flavonoids (28.44 mg QE /g). Main lignans were identified by TLC and UHPLCMS. Although the SAO sample showed higher values than MAQ for both phenolic content and biological activities, no statistically significant differences were determined.