do u know how to do the MIC test in this case?

[mandy82]

i am doing my research, antimicrobial by plant extract. after get the result from paper disc test, i need to confirm the concentration of extract which can kill the bacteria. i decided use the MIC (minimum inhibitory concentration) method. the principle of this method is compare the turbidity with the control. if it is turbid, it means, bacteria are growing. however, my plant extract is very dark in colour, when i mix with the MH broth, it become brown in colour, and cant compare the turbidity... thus, anyone here can give me some suggestion how to settle this problem? thanks very much!

[canalon]

I would use a spectrophotometer and run a spectral analysis on your extract. Find a certain number of wave length where the transmission is good and then adding defined quantities of bacteria in the extract, (read immediatly it's just to have a standard) see if the transmission value are evolving in a way that allow me to use this particular wavelength for evaluating bacterial growth.