Propolis is a resin that honey bees (Apis mellifera) produce by mixing wax, exudates collected from tree shoots, pollen, and enzymes. It has been used for its biological properties against pathogenic microorganisms including those of viral origin. In the present study, we demonstrate the antiviral effect of Mexican propolis, as well as of the three commercial flavonoids (quercetin, naringenin, and pinocembrin) present in its composition, in cell cultures infected with Canine Distemper Virus. The treatments were carried out with propolis, flavonoids individually, and a mixture of the three flavonoids at three different times. Antiviral activity was evaluated by the inhibition of the relative expression of the virus nucleoprotein gene (Real‐Time qPCR) and by the determination of cellular viability (MTT assay). Propolis applied before infection decreased viral expression (0.72 versus 1.0, 1.65, and 1.75 relative expressions) and correlated with increased cell viability (0.314 versus 0.215, 0.259, and 0.237 absorbance units (AU)). The administration of a flavonoid mixture containing the three commercial flavonoids before infection induces a slight decrease in viral expression (0.93 versus 1, 1.42, and 1.82 relative expressions); however, it does not improve cellular viability (0.255 versus 0.247, 0.282, and 0.245 AU). Quercetin administrated at the same time of infection decreases viral expression (0.90 versus 1.0, 3.25, and 1.02 relative expressions) and improves cellular viability (0.294 versus 0.240, 0.250, and 0.245 AU). Pinocembrin and naringenin individually did not show any antiviral activity at the administration times evaluated in this study. The present work is the first in vitro study of the effect of propolis in Canine Distemper Virus and demonstrated the antiviral activity of Mexican propolis, in addition to the synergy that exists between the three flavonoids on cell viability and the expression of the nucleoprotein virus gene.

In this paper, the results obtained in the synthesis of thioamides and α-ketothioamides by a modification of the Willgerodt–Kindler reaction, under solvent-free and noncatalyst conditions using IR energy as a source of activation, are presented. The use of IR energy in these reactions has been shown to lead to a mixture of thioamide and α-ketothioamide as the main products in most cases, with the latter predominating. The yields of α-ketothioamides from most of these reactions are better than those reported previously. To the best of our knowledge, this is the first time that IR energy has been applied to promote the Willgerodt–Kindler reaction.

En México, los propóleos se ofertan por su actividad antioxidante y su actividad antimicrobiana, por lo cual es necesario realizar su análisis utilizando la norma de calidad mexicana. El objetivo del presente estudio fue analizar la composición química de ocho propóleos mexicanos colectados de diferentes municipios de los estados de México, Michoacán, Guanajuato, Veracruz y Puebla, para evaluar su actividad antioxidante y también su actividad antimicrobiana contra cepas de referencia de Staphylococcus aureus, Escherichia coli y Candida albicans. Las muestras provenientes de los municipios del Estado de México y Michoacán presentaron flavonoides, fenoles y terpenos que les confieren una mayor actividad antioxidante y acción antimicrobiana. Las muestras de los municipios de Puebla, Veracruz y Guanajuato contienen terpenos en bajas cantidades, provocando disminución de la actividad biológica e incumplimiento de las especificaciones de calidad. Se demostró la importancia del estudio de la composición química de los propóleos que se asocia a su actividad biológica en pruebas específicas.