Estudio de propiedades moleculares de cuatro flavonoides de Baccharis boliviensis / Study of molecular properties of four flavonoids of baccharis boliviensis

En este trabajo de investigación se realizó un estudio de relación estructura y actividad antioxidante empleando métodos computacionales basándose en propiedades estructurales y electrónicas, para lograr este objetivo se utilizó el programa computacional Hyperchem versión 8.0.1 empleando métodos cuánticos semiempiricos, a partir de las estructuras más estables obtenidas se calcularon longitudes de enlace, cargas atómicas, entalpias de disociación de enlace y orbitales moleculares de los cuatro flavonoides de Baccharis boliviensis aislados e identificados por el grupo de investigadores de Almanza, G. et.al en el año 2012. Al relacionar todos los datos obtenidos con la capacidad antioxidante se encontró que la actividad antioxidante entre los cuatro flavonoides el flavonoide 4 tiene mayor capacidad antioxidante debido al mayor número de grupos hidroxilo y a los valores bajos de energía de disociación de enlace EDE relativa respecto al flavonoide 1 que ocuparía el segundo lugar en términos de capacidad antioxidante, apoyan a estos resultados el hecho de considerar los valores de la segunda diferencia de energía de disociación de enlace EDE entre estos dos flavonoides se obtiene una diferencia de 1.106 H (Hartrees) para el flavonoide 4 y 1.4651H para el flavonoide 1. Los flavonoides 2 y 3 ocuparían las posiciones 3 y 4 en términos de capacidad antioxidante respectivamente. En conclusión la actividad antioxidante de los cuatro flavonoides estudiados presenta el siguiente orden de mayor a menor actividad antioxidante: flavonoide 4 > flavonoide 1 > flavonoide 2 > flavonoide 3.

In this research work was carried out a study of relationship structure and antioxidant activity using computational methods based on structural and electronic properties, to achieve this objective we used the computer program Hyperchem version 8.0.1 using semiempirical quantum methods, from structures More stable, bond lengths, atomic charges, bond dissociation enthalpies and molecular orbitals of the four Baccharis boliviensis flavonoids isolated and identified by the Almanza group, G Et.al in 2012, were calculated. By relating all the data obtained with the antioxidant capacity it was found that the antioxidant activity among the four flavonoids flavonoid 4 has higher antioxidant capacity due to the higher number of hydroxyl groups and the lower energy values of linkage dissociation EDE relative to flavonoid 1 that would occupy the second place in terms of antioxidant capacity, support to these results the fact of considering the values of the second energy difference of linkage dissociation EDE between these two flavonoids gives a difference of 1,106 H (Hartrees) for the flavonoid 4 and 1.4651H for flavonoid 1. The flavonoids 2 and 3 would occupy positions 3 and 4 in terms of antioxidant capacity respectively. In conclusion the antioxidant activity of the four flavonoids studied has the following order of highest to lowest antioxidant activity: Flavonoid 4> flavonoid 1> flavonoid 2> flavonoid 3.

Inhibition of cyclooxygenase activity by standardized hydroalcoholic extracts of four Asteraceae species from the Argentine Puna

We determined the anti-inflammatory activity of standardized extracts of four medicinal plant species (Baccharis incarum, B. boliviensis, Chuquiraga atacamensis, Parastrephia lucida) that grow in the Argentine Puna (3800 m above sea level) and that are used to reduce oxidative stress and alleviate gout and arthritic pain. The extracts of plant aerial parts were standardized in terms of total phenolic compounds and flavone/flavanone content and free radical scavenging activity. All extracts showed high phenolic compound concentration (0.5-1.6 mg/mL), mainly flavones and flavonols (0.1-0.8 mg/mL). The extracts showed hydrogen donating ability (DPPH and ABTS) and reactive oxygen species scavenging activity (O2●-, OH-, H2O2). The ability of the extracts to inhibit cyclooxygenase enzymes (COX-1 and COX-2) was determined by calculating percent inhibition of PGE2 production measured by enzyme immunoassay. All extracts inhibited both enzymes with IC50 values of 2.0 to 16.7 µg/mL. The anti-inflammatory activity of B. incarum and C. atacamensis extracts was higher than that of B. boliviensis and P. lucida. The IC50 values obtained for indomethacin were 0.11 and 0.78 µM for COX-1 and COX-2, respectively. The present results are consistent with the anecdotal use of these species in phytotherapic preparations.