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.
ABSTRACT
OBJECTIVE:To establish a method for the contents determination of phospholipid and γ-linolenic acid in Com-pound linolenic acid soft capsule. METHODS:HPLC was conducted to determine the content of soybean lecithin;the column was Agilent TC-C18 with mobile phase of methanol-water(84:16,V/V)at a flow rate of 1.0 ml/min,the detection wavelength was 219 nm,the column temperature was 30 ℃,and the injection volume was 10 μl.Gas chromatography was conducted to determine the content of γ-linolenic acid in the preparation;the column was DB WAX,injector temperature was 210 ℃ by temperature pro-grammed,carrier gas was helium at a flow rate of 1 ml/min by split injection(split ratio of 1:30),and the injection volume was 0.02μl. RESULTS:The linear range was 4.64-16.24μg/ml for phospholipid(r=0.999 6)and 0.093 44-0.327 04μg/ml forγ-linole-nic acid methy ester(r=0.999 6);RSDs of precision,stability and reproducibility tests were lower than 3%;recoveries were 97.44%-99.36%(RSD=0.93%,n=6) and 97.22%-99.07%(RSD=1.01%,n=6),respectively. CONCLUSIONS:The method is simple,stable with good separation,and can be use for the contents determination of phospholipid and γ-linolenic acid in Com-pound linolenic acid soft capsule.
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.
ABSTRACT
A combination technique of LC/ESR, LC/MS and spin trapping was used to identify and characterize the carbon-centered free radicals formed from lipoxygenase-catalyzed peroxidation of dihomo-γ-linolenic acid(DGLA). The spin trap, α-[4-pyridyl-1-oxide]-N-tert-butyl nitrone(POBN), could react with short-lived carbon-centered radicals to form relatively stable adducts. Based on the same retention time of POBN radical adduct in LC/UV/ESR and LC/MS, molecular weight of adduct could be confirmed and the structure of adduct could be confirmed by their LC/MS2 fragment pattern. The results showed that free radicals formed in lipoxygenase-catalyzed peroxidation of DGLA, including ~·C_7H_(13)O_2, ~·C_(10)H_(17)O_2 and ~·C_5H_(11), all stemmed from β-scission of DGLA alkoxyl radicals(8-, 11-, 15-LO~·). The results were helpful for further study of biological activities of these radicals in vivo.