等离子活化水对耐药结核分枝杆菌体外抑菌效果评估

Objective To evaluate the in vitro antibacterial activity of plasma-activated water (PAW) against drug-resistant Mycobacterium tuberculosis (MTB), and to provide a theoretical basis for adjuvant treatment of drug-resistant tuberculosis or disinfection of the environment and medical devices. Methods Select the standard MTB strain H37Rv stored in the tuberculosis laboratory of the Tuberculosis Prevention and Control Hospital in Shaanxi Province, and determine the in vitro antibacterial effect of PAW on MTB under different solution media, activation water preparation time, concentration and treatment time; using the colony counting method to calculate the PAW inhibition rate as the result determination standard, and evaluating the antibacterial effect of PAW on drug-resistant MTB (including 6 rifampicin-resistant MTB strains, 2 multidrug-resistant MTB strains and 2 extensively drug-resistant MTB strains. Results The minimum inhibitory concentration (MIC) of plasma-activated physiological saline (PAS) after 25 minutes of activation was 12.5%, which was lower than 25% of that of plasma-activated distilled water (PAD); after treatment for 10, 20, 30, and 60 minutes, the colony counts of 50% and 75% PAS for MTB were (54.11±1.38) × 102 and (41.89±1.92) ×102 CFU/mL, (38.78±1.01) × 102 and (21.33±1.03) × 10²CFU/mL ，respectively, and the bacterial counts after incubation with 75% PAS were significantly lower than those with 50% PAS (F=662.398, 802.605, both P<0.001); the inhibition rates of 50% and 75% PAS for the H37Rv standard strain after incubation for 20 and 30 minutes were 98.5% and 98.8%, 98.9% and 99.4%, respectively, and the inhibition rates of 75% concentration PAS after incubation for different times were higher than those of 50% PAS; the inhibition rates of 75% concentration PAS for 10 clinical isolates of drug-resistant MTB treated were all > 90%, indicating that PAS has a strong inhibitory effect on drug-resistant MTB. Conclusion PAS exhibits excellent in vitro anti-MTB activity and has potential application value in assisting physical treatment for drug-resistant tuberculosis or in the disinfection of the environment and medical devices.