What is agar well diffusion?

Answer 1

The extracts obtained from the plants or any antibiotic preparations were used for studying their antibacterial activity. A loop full of bacterial strain was inoculated in 30 ml of Nutrient broth in a conical flask and incubated for 72 hrs to get active strain by using agar well diffusion method. Muller Hinton Agar was poured into Petri dishes. After solidification 0.25 ml of test strains were inoculated in the media separately. Care was taken to ensure proper

homogenization. The experiment was performed under strict aseptic conditions. After the medium solidified, a well was made in the plates with sterile borer (5mm).The extract compound (50 μl) was introduced into the well and plates were incubated at 37°C for 72 hrs. All samples were tested in triplicates. Microbial growth was determined by measuring the diameter of zone of

inhibition14. A control with standard antibiotic was kept for all test strains and the control activity was deducted from the test and results were recorded.

Answer 2

It is a type of test; (soft) agar, a Jell-O like substance, is poured onto a plate and when it solidifies small holes or 'wells' are dug out and filled with a desired substance or solution.

Bigger molecules won't be able to diffuse through the agar. Sometimes multiple wells are made a short distance away from each other to test if two diffused substances will form a precipitate when they meet (which shows up as a cloudy area in the agar).