Phytochemical Screening of Antimicrobials from Allium cepa

Allium cepa belongs to family Apiaceae, is a hebaceous annual plant spread throuout India. It is commonly known Onion or Pyaz in India. The present study renders the preliminary phytochemical screening and antimicrobial activity of Allium cepa. In the present study two bacteria were tested for their antimicrobial susceptibility against Petrolum ether, Acetone and Methanolic extract of plant. The antimicrobial activity of plant extracts were assayed using well diffusion method. The results showed alkaloids, flavnoids, steroids, phenols, amino acids, glycosides, tannins triterpanoids and carbohydrates are present different extracts. Antimicrobial effects of methanolic extract show the highest inhibition against E. coli and B. Subtilis. Acetone extract shows minimum Inhibitory effect against E. coli and B. Subtilis. This study provides evidence for the presence of one or more soluble constituents in the plants used, that probably interferes with bacterial growth and their metabolism which would prevent and inhibit initiation and progression of many diseases.