Green nanotechnology is an important and environmentally friendly technology that is applicable in various areas, such as health and food. The following study demonstrates the possibility of synthesizing silver nanoparticles obtained from Portulaca oleracea callus to determine their effectiveness against pathogenic bacteria. Silver nanoparticles’ synthesis from P. oleracea callus samples used four different pH values (3, 7, 10, and 12). Samples at a pH value of 12 with the smallest particle showed the best results after conducting SEM and UV-Vis analyses. The results revealed the reaction samples with higher pH values gave effects that are more positive. Effectiveness of the nanoparticles against the bacterial activity of Escherichia coli (E. coli) was successful, and the results were favorable, with an inhibition diameter of 9 mm. The nanoparticles, in combination with plant extracts of nodes and stem callus, had the mixed samples exhibiting the best activity and a more powerful effect than the silver nanoparticles alone. The sample of node extract and the nanoparticles had the most powerful effect on the bacteria, with an inhibition diameter of 22 mm. However, the sample with the stem extract and nanoparticles had an inhibition diameter of 11 mm.

Keywords: P. oleracea, antibacterial activity, SEM and UV-Vis, silver nanoparticles

Key findings: Silver nanoparticles produced from P. oleracea callus showed that the reaction samples with higher pH values emerged with results that are more positive. Integrating nanoparticles with plant extracts revealed effectiveness against E. coli bacteria.