title: Evaluation of anti-tubercular activity of linolenic acid and conjugated-linoleic acid as effective inhibitors against Mycobacterium tuberculosis.
abstract: OBJECTIVE
  To evaluate a new pharmacological activity/effect of linolenic acid (α- and γ-form) and conjugated-linoleic acid (CLA) causing antibacterial activity against Mycobacterium tuberculosis (Mtb).
  
  
  METHODS
  The anti-Mtb activity/effect of linolenic acid and CLA were determined using different anti-Mtb indicator methods such as resazurin microtiter assay (REMA) and MGIT 960 system assay. The Mtb was incubated with various concentrations (12.5-200 μg/mL) of the compounds and anti-Mtb first-line drugs for 5 d in the REMA, and for 3 wk in MGIT 960 system assay.
  
  
  RESULTS
  Linolenic acid and CLA obviously indicated their anti-Mtb activity/effect by strongly inhibiting the growth/proliferation of Mtb in a dose-dependent manner in the REMA and the MGIT 960 system assay. Interestingly, linolenic acid and CLA consistently induced anti-Mtb activity/effect by effectively inhibiting the growth/proliferation of Mtb in MGIT 960 system for 21 d with a single treatment, and their minimum inhibitory concentrations were measured as 200 μg/mL respectively.
  
  
  CONCLUSIONS
  These results demonstrate that linolenic acid and CLA not only have effective anti-Mtb activity/properties, but also induce the selective-anti-Mtb effects by strongly inhibiting and blocking the growth/proliferation of Mtb through a new pharmacological activity/action. Therefore, this study provides novel perspectives for the effective use of them and the potential that can be used as potent anti-Mtb candidate drugs, as well as suggests the advantage of reducing the cost and/or time for developing a new/substantive drug by effectively repurposing the existing drugs or compounds as one of new strategies for the global challenge of tuberculosis.
authors.affiliation: Department of Biomedical Science, Kyung Hee University School of Medicine, 26 Kyunghee-daero, Dongdaemun-gu, Seoul 130-701, Republic of Korea; Department of Medical Zoology, Kyung Hee University School of Medicine, 26 Kyunghee-daero, Dongdaemun-gu, Seoul 130-701, Republic of Korea. Electronic address: whchoi@khu.ac.kr.
authors.forename: Won Hyung
authors.initials: WH
authors.lastname: Choi
keywords: Drug susceptibility testing; MGIT 960 system; Tuberculosis; γ-Linolenic acid