All are similar in the context of their measurement. But, IC50 is used generally for chemical assays like oxidation /reduction or other colorimetric/ fluorimetric assays where one chemical concentration inhibits 50% of these processes (Even for CFU measurements for Bacterial growth inhibition).
Whereas LC/LD50 will be applicable to animals (rats, mice..etc). In between LC50 and LD50, certainly LD50 will be used to represent the drugs /chemical which will kill 50% population of animals in single oral administration & where as LC50 will be used to show the concentration of a chemical in air exposed for 4hr to kill 50%of population.
So, According to OECD LC50 shows the lethal conc. of a chemical in air exposed for 4hr to kill 50% of population during observation (generally 14 days) where as for single oral/dermal dose of that chemcial to kill 50% population generally referred as a lethal Dose LD50.
All are similar in the context of their measurement. But, IC50 is used generally for chemical assays like oxidation /reduction or other colorimetric/ fluorimetric assays where one chemical concentration inhibits 50% of these processes (Even for CFU measurements for Bacterial growth inhibition).
Whereas LC/LD50 will be applicable to animals (rats, mice..etc). In between LC50 and LD50, certainly LD50 will be used to represent the drugs /chemical which will kill 50% population of animals in single oral administration & where as LC50 will be used to show the concentration of a chemical in air exposed for 4hr to kill 50%of population.
So, According to OECD LC50 shows the lethal conc. of a chemical in air exposed for 4hr to kill 50% of population during observation (generally 14 days) where as for single oral/dermal dose of that chemcial to kill 50% population generally referred as a lethal Dose LD50.
I would be cautious about using IC50 values for bacterial growth inhibtion data, it depends on the shape of your dose-response curve. In my experience performing liquid microtitre plate based growth inhibition assays with yeast, the curves are not the typical sigmoidal curves you see in other dose-response type experiments. Most software will model the dose-response data to a sigmoidal curve, however if the ascending portion is very steep, the error associated with the caluculated IC50 value often exceeds the IC50 value itself. In this case I tend to favour MIC values. You should always plot your data and let the shape of the curve determine what value you will calculate/report.
LC 50 mean mean lethal concentration. It means the concentration of the toxicant that produced 50% mortality in the test animals used in the bioassay test. LD 50 means mean lethal time or than period of time in hours or days that produced mortality of 50% in the test animals