Staphylocodycus Aureus Lab Report
2. Material and methods
2.1 Sample collection
The following 14 samples of Staphylococcus aureus were used in this study. All samples were obtained from food contact surfaces at three food premises in University of Putra Malaysia (UPM). Samples were collected from the surface of each material according to standard swabbing techniques. The collection was carried out during weekdays (15:00-17:00) after finished the preparation of foods. Sterile swabs were removed from the coded test tubes that contain 5 ml of sterile phosphate buffered saline with pH 7.4±1 (Oxoid, Basingstoke, UK) and the targeted areas on the cutting board, tray, plate and wok were swabbed.
Sampling has been done by swabbing all of these surfaces horizontally, vertically and diagonally by using standard templates with the size of 10 cm x 10 cm. The whole procedure will be carried out aseptically to minimize the risk of contamination. After swabbing, samples were put back into their respective …show more content…
aureus were maintained on Tryptic Soy agar (TSA), following incubation at 37 oC for 24 h. Inocula were obtained from overnight fresh cultures adjusted to approximately log 108 CFU/ml, a turbidity equivalent to a 0.5 McFarland standard (Kroning et al., 2016). The inocula were spread on the surface of Mueller-Hinton agar (MHA) plates. The disk diffusion test, recommended by the Clinical and Laboratory Standards Institute (CLSI, 2015), was employed to determine the resistance to 11 antimicrobials: ciprofloxacin (5 µg), amoxicillin (10 µg), gentamicin (10 µg), penicillin G (10 µg), ceftriaxone (5 µg), sulphafurazole (300 µg), streptomycin (25 µg), ceftazidime (30 µg), cephalothin (30 µg), nalidixic acid (30 µg), cefotaxime (30 µg) purchased from the company Mayang Scientific®. The results were interpreted in accordance with the standards for inhibition zone diameters for Staphylococcus spp. (CLSI, 2015). Staphylococcus aureus ATCC 13565 was used as the positive control for the
2.1 Sample collection
The following 14 samples of Staphylococcus aureus were used in this study. All samples were obtained from food contact surfaces at three food premises in University of Putra Malaysia (UPM). Samples were collected from the surface of each material according to standard swabbing techniques. The collection was carried out during weekdays (15:00-17:00) after finished the preparation of foods. Sterile swabs were removed from the coded test tubes that contain 5 ml of sterile phosphate buffered saline with pH 7.4±1 (Oxoid, Basingstoke, UK) and the targeted areas on the cutting board, tray, plate and wok were swabbed.
Sampling has been done by swabbing all of these surfaces horizontally, vertically and diagonally by using standard templates with the size of 10 cm x 10 cm. The whole procedure will be carried out aseptically to minimize the risk of contamination. After swabbing, samples were put back into their respective …show more content…
aureus were maintained on Tryptic Soy agar (TSA), following incubation at 37 oC for 24 h. Inocula were obtained from overnight fresh cultures adjusted to approximately log 108 CFU/ml, a turbidity equivalent to a 0.5 McFarland standard (Kroning et al., 2016). The inocula were spread on the surface of Mueller-Hinton agar (MHA) plates. The disk diffusion test, recommended by the Clinical and Laboratory Standards Institute (CLSI, 2015), was employed to determine the resistance to 11 antimicrobials: ciprofloxacin (5 µg), amoxicillin (10 µg), gentamicin (10 µg), penicillin G (10 µg), ceftriaxone (5 µg), sulphafurazole (300 µg), streptomycin (25 µg), ceftazidime (30 µg), cephalothin (30 µg), nalidixic acid (30 µg), cefotaxime (30 µg) purchased from the company Mayang Scientific®. The results were interpreted in accordance with the standards for inhibition zone diameters for Staphylococcus spp. (CLSI, 2015). Staphylococcus aureus ATCC 13565 was used as the positive control for the