In vitro antimicrobial activities of animal-used quinoxaline 1, 4-di-N-oxides against mycobacteria, mycoplasma and fungi. Issue 1 (December 2016)

• Record Type: Journal Article
• Authors: Zhao, Yan; Cheng, Guyue; Hao, Haihong; Pan, Yuanhu; Liu, Zhenli; Dai, Menghong; Yuan, Zonghui
• Is Part Of: BMC veterinary research. Volume 12:Issue 1(2016)
• Page Start: 1
• Page End: 13
• Publication Date: 2016-12
• Subjects: Quinoxaline 1, 4-di-N-oxides -- Antituberculosis -- Antimycoplasma -- Antifungi -- Combined antimicrobial susceptibility test; Veterinary medicine -- Research -- Periodicals; Veterinary medicine -- Periodicals; 636.0890724
• DOI: 10.1186/s12917-016-0812-7
• Languages: English
• ISSNs: 1746-6148

Abstract

Abstract Background The quinoxaline 1, 4-di-N -oxides (QdNOs) were known as potent antibacterial agents. For the purpose of evaluating the bioactivity of existing animal-used QdNOs drugs against representative pathogenic microorganism, the representative drugs of quinoxalines including cyadox, mequindox, quinocetone and their metabolites were submitted to the in vitro evaluation for antituberculosis, antimycoplasma, antifungal and antiviral activities. Results In antituberculosis assays, the prototype compounds were active (MIC = 4 ~ 8 μg/mL) againstMycobacterium tuberculosis H37Rv andM. bovis. Combined antimicrobial susceptibility test indicated that cyadox, mequindox and quinocetone combined with rifampicin had additive effect againstM. tuberculosis complex with Fractional Inhibitory Concentration Index (FIC) of 0.75. Results of antifungal assays showed that quinocetone was active againstMicrosporum canis with MIC of 8 μg/mL. Antimycoplasma screening showed a generally good activity of quinocetone againstMycoplasma gallisepticum andMycoplasma hyopneumoniae, with MIC between 8 and 16 μg/mL. As shown from the combined antimicrobial susceptibility test, cyadox, mequindox and quinocetone combined with tetracycline had additive effect againstMycoplasma gallisepticum with FIC of 0.75. These compounds were also submitted to antiviral assay against infectious bursal disease virus, porcine reproductive and respiratory syndrome virus, porcine parvovirus and classical swine fever virus. The results obtained showed that these QdNOs and their metabolites have no inhibitory activity against these viruses in vitro. Conclusions QdNOs exhibit antimicrobial activities against mycobacteria, mycoplasma and fungi. This study gives new insight in further application of QdNOs and offers a way to promote the healthcare of animal husbandry.