摘要：The antimicrobial activity of plant extracts and phytochemicals was evaluated with antibiotic susceptible and resistant micro organisms. Methanolic extract of Opuntia dillenii (OD) was tested for its antibacterial (plate hole method) activity against fourteen different bacterial strains. From the results, it is deduced 100 % of methanolic extract were active in concentration of 1000 μg/ml, 93 % active in concentration of 500 μg/ml, 87.5 % active in concentration of 250 μg/ml, 50 % active in concentration of 125 μg/ml and no activity in lowest test concentration of 62.5 μg/ml. Antifungal activity against six different fungal organisms were studied and the results were indicated that the 1000 μg/ml & 500 μg/ ml showed good activity in all fungus (100%). The methanolic extracts in concentration of 250 μg/ml (83%) and 125 μg/ ml (33 %) showed moderate activity in all tested microorganisms. Oxy tetracycline and Amphotericin B with concentration of 1000 μg/ml were used as a standard drug for antibacterial and antifungal studies respectively. Keywords : Antibacterial ; Antifungal ; Opuntia dillenii.
