Campypak

Susceptibility testing of erythromycin, tetracycline and ciprofloxacin was performed for 148 isolates of Campylobacter spp. obtained from patients in northern (n = 77) and southern (n = 71) Taiwan from 2013 to 2014 by using the disk diffusion method. The disk diffusion protocol, quality control and the interpretative criteria used were based on the CLSI guidelines (Clinical and Laboratory Standards Institute, 2016 ). Culture condition is Mueller Hintion agar with 5% sheep blood, 42°C for 48 h in a microaerophilic atmosphere(CampyPak; BBL; Becton Dickinson, Rutherford, NJ, United States).

The E-test was performed for 75 isolates (40 from northern and 35 from southern Taiwan) selected randomly from the 148 isolates obtained during 2013–2014; erythromycin, ciprofloxacin, and tetracycline were used for this test. The MICs of erythromycin, ciprofloxacin, and tetracycline for the Campylobacter isolates were determined using the standard E-test method. After inoculation with McFarland 0.5 turbidity standard Campylobacter culture, 90-mm plates containing E-test strips (AB BIODISK, Solna, Sweden) were incubated at 42°C for 48 h in a microaerobic environment (CampyPak; BBL; Becton Dickinson, Rutherford, NJ, United States). Quality control is the operation of C. jejuni ATCC 33560.

Gram-Negative Bacterial Strains. The Gram-negative bacterial strains were periodontopathic bacteria Aggregatibacter actinomycetemcomitans (HK 1519) and Porphyromonas gingivalis (ATCC 33277).
Gram-Positive Bacterial Strains. The Gram-positive bacterial strains were cariogenic bacteria Streptococcus mutans (CCUG 27624) and Lactobacillus acidophilus (NCTC 1723) and the nonoral pathogenic bacterium Bacillus megaterium (BM11).
Growth Conditions. All the bacteria were propagated as previously described [18 (link)]. Briefly, A. actinomycetemcomitans was propagated on Columbia base agar (Acumedia, Baltimore, MD, USA) supplemented with 0.1% tryptophan (Merck, VWR International, Sweden) and 5% citrated horse blood in 5% CO₂ atmosphere (CampyPak, Becton Dickinson, Sweden). P. gingivalis was propagated for 6 days on Colombia base agar supplemented with hemin (0.05 mg/mL), vitamin K (0.01 mg/mL) (BBL, Becton Dickinson, Sweden), and 5% citrated horse blood in an anaerobic atmosphere (GasPak, Becton Dickinson, Sweden). S. mutans was grown in Brain-Heart Infusion (BHI) agar plates (Oxoid, Malmo, Sweden) for 2 days in 5% CO₂ atmosphere. L. acidophilus was propagated for two days on Lactobacilli MRS agar plates (Difco, Becton Dickinson, Sweden) in 5% CO₂. B. megaterium was propagated overnight in air on Luria Agar plates (Difco). All bacteria were incubated at 37°C.