Investigation of the anti-fungal activity of coptisine on Candida albicans growth by microcalorimetry combined with principal component analysis.
OBJECTIVE
This study investigated the anti-fungal activity of coptisine on Candida albicans growth.


RESULTS
The metabolic power-time curves of Candida albicans growth at 37 degrees C affected by coptisine were measured by microcalorimetry using an LKB-2277 Bioactivity Monitor with stop-flow mode. Then, the diameter of inhibitory zones in the agar layer was observed using agar cup method, and the minimal inhibitory concentration (MIC) of coptisine on Candida albicans growth was determined by serial dilution method. From the principal component analysis on nine quantitative parameters obtained from the power-time curves, we could easily evaluate the anti-fungal activity of coptisine by analysing the change of values of the main two parameters, growth rate constant k and maximum power output in the log phase P(m, log). The results showed that coptisine had strong anti-fungal activity: at a low concentration (45 microg ml(-1)) began to inhibit the growth of Candida albicans and at a high concentration (500 microg ml(-1)) completely inhibited Candida albicans growth. Coptisine gave big inhibitory zones with diameters between 11 and 43 mm within test range, and the MIC of it was 1000 microg ml(-1).


CONCLUSIONS
Coptisine had strong anti-fungal activity on Candida albicans growth. The method of microcalorimetry applied for the assay of anti-fungal activity of coptisine was quantitative, sensitive and simple.


CONCLUSIONS
This work will provide useful information for the development of chemical biology policy in the use of anti-microbials in food and drug production.
Kong
W-J
WJ
PLA Institute of Chinese Materia Medica, Hospital of People's Liberation Army, Beijing 100039, China. kongwj302@126.com
Zhao
Y-L
YL
Xiao
X-H
XH
Li
Z-L
ZL
Jin
C
C
Li
H-B
HB
D000935:Antifungal Agents / Q000494:pharmacology*; D001599:Berberine / Q000031:analogs & derivatives* / Q000494:pharmacology; D002151:Calorimetry / Q000379:methods; D002176:Candida albicans / Q000187:drug effects* / Q000254:growth & development; D007700:Kinetics; D008826:Microbial Sensitivity Tests; D025341:Principal Component Analysis
D000935:Antifungal Agents; C034384:coptisine; D001599:Berberine