Materials and methods
Method
A modified disc diffusion method was used for determination of the antibacterial activities of the Nigella Sativa ground seeds with water (NSGSW), and the following steps were carried out:
The equipment used were cleaned and sterilized by immersing them in ethanol for 10 min then washed with distill water(D.W.) and dried adequately by using sterile bandage.
Nigella sativa HNS and ENS were ground by the grinding machine and then put in two separate bottles, one for HNS and the other for ENS.
0.75gm of both type of Nigella sativa from the two separated bottles was measured by using sensitive balance, and transferred with aid of spatula into separate test tubes covered with foil. 2.5ml D.W. was added to each test tube in microbiology laboratory.
2 agar plates were taken and divided to equal 4 regions or 3 regions as required.
The nutrient broth was inoculated with a loopful of the selected bacteria and the plain agar was also inoculated with the broth containing this bacteria.
The test tubes were shaken vigorously to form homogenous mixture and in first plate ENSGSW in region (1) 5 µl of mixture was added, in region (2) 10 µl mixture and in region (3)20 µl of mixture was added, in region (4) 10ml of D.W used as a negative control and in the second plate, by using 20 micropipette, 20 µl of HNSGSW was placed to region (1) and 20µl of ENSGSWto region (2) in region (3) positive control was added (Antimicrobial standard Azithromycin and Ciprofloxacin).
Finally, the tested plates were placed in the incubator at 37°C for 24 hrs, and for the assessment of the results, pictures of the Petri plates were taken at the end of each experiment and the inhibition zones around each paper disc (5mm diameter, filter paper) were measured and recorded.