Green Synthesis of Chromium Nanoparticles by Aqueous Extract of Melia azedarach, Artemisia herba-alba and Bacteria Fragments against Erwinia amylovora

This study was carried out at the Tissue Culture and Germplasm Conservation Research Laboratory, Horticulture Research Institute, Agricultural Research Center, Giza, Egypt. in cooperation with Department of Horticulture, Faculty of Agriculture, Benha University, Egypt. from 2016 to 2020.

Medicinal plants contain many reduction substances e.g. terpenoids, flavonoids, tannins, and glycosides. Melia azedarach and Artemisia herba-alba are rich in these compounds that are able to reduce chromium metal (VI) to chromium nanoparticles (Cr2O3). Chromium oxide nanoparticles were green synthesized by the reduction of potassium dichromate solution with Melia azedarach and Artemisia herba-alba plant extract. In biological methods, Cr2O3 nanoparticles were synthesized by two biological agents of Erwinia amylovora dry matter and extraction. The resulting Cr2O3 nanoparticles were characterized by transmission electron microscopy (TEM), UV-VIS absorption spectroscopy. The antibacterial effect of Cr2O3 nanoparticles against E. amylovora gave the highest inhibition zone for Cr2O3 nanoparticles reduction by Artemisia followed by Melia (31.0 and 25.0 mm respectively). These particles were shown to have an effective bactericide on contaminated callus pear cells by Erwinia bacteria which gave survival 75% and 50% and 0.0% contamination.