Green Synthesis and Antiproliferative Activity of Gold Nanoparticles of a Controlled Size and Shape Obtained Using Shock Wave Extracts from Amphipterygium adstringens.

In this study, green chemistry was used as a tool to obtain gold nanoparticles using Amphipterygium adstringens extracts as a synthesis medium. Green ethanolic and aqueous extracts were obtained using ultrasound and shock wave-assisted extraction. Gold nanoparticles with sizes ranging between 100 and 150 nm were obtained with ultrasound aqueous extract. Interestingly, homogeneous quasi-spherical gold nanoparticles with sizes between 50 and 100 nm were achieved with shock wave aqueous-ethanolic extracts. Furthermore, 10 nm gold nanoparticles were obtained by the traditional methanolic macerate extraction method. The physicochemical characteristics, morphology, size, stability, and Z potential of the nanoparticles were determined using microscopic and spectroscopic techniques. The viability assay in leukemia cells (Jurkat) was performed using two different sets of gold nanoparticles, with final IC50 values of 87 µM and 94.7 µM, reaching a maximum cell viability decrease of 80% The results do not indicate a significant difference between the cytotoxic effects produced by the gold nanoparticles synthesized in this study and vincristine on normal lymphoblasts (CRL-1991).

Vasorelaxing effect and possible chemical markers of the flowers of the Mexican Crataegus gracilior.

The vasorelaxing effect of the methanol extract of the flowers of Crataegus gracilior, a Mexican medicinal plant used to treat some cardiovascular diseases, was assessed, and its possible chemical markers identified. The extract produced a potent vasodilator effect on isolated rat aortic rings (EC50 = 1.83 ± 1.39 µg/mL; Emax = 100 ± 3.4%). Vitexin, the most commonly identified flavonoid in the flowers and used to standardise some Crataegus species, was not found at all in this plant sample. Instead, daucosterol, and corosolic and euscapic acids were purified. The two triterpene acids have been reported to possess beneficial effects on cardiovascular diseases. These results indicate that the vasodilator effect might induce the hypotensive effect claimed by users, and that euscapic and corosolic acids may be the main vasodilator compounds, and can then be employed as the chemical markers towards the future standardisation of the extract.