Effect of heavy metal on the in vitro growth of Paronchia argentea and its antimicrobial activity

Abstract

Paronchia argentea is traditionally being used for medicinal purposes in Jordan. The current investigation was de-signed to check the in vitro efficacy of in vitro and ex vitro P. argentea against selected bacterial and fungal strains. The antimicrobial properties of in vitro plantlets and field (ex vitro) plant extracts of P. argentea were investigated against both bacteria and fungi, after and before heavy metals stress used. In this study, four bacterial species were used: Listeria monocytogen and Staphylococcus aureus (Gram positive bacteria) Salmonella typhimurum and Coronobacter sakazakii (Gram negative bacteria) and Calvularia lunata as a mold. The obtained results revealed that the in vitro grown plantlets with the supplemented of lead (Pb), copper (Cu) or Cobalt (Co) with methanol and aqueous extract showed significant inhibitory activities within zones of inhibition ranging between 6.7-30.0 mm. All extracts of P. argentea had activity against the fungi and bacteria tested. The maximum inhibition zone was found in Staphylococcus aureus (30 mm inhibition zone) in medium supplemented with 0.3 mg/L Cu followed by Calvularia lunata (30.0 mm inhibition zone). The methanolic and aqueous P. argentea extract indicate that the solvent plays an important role in the solubility of the antimicrobial substance and also affects the activity of the microbe. Both field (ex vitro) and tissue culture plant extract showed similar antimicrobial activity. The present study could be used as an approach for the development of new, alternative and cheap antimicrobial drugs, particu-larly against the infections caused by the tested microbes through the tissue culture technology.