FIELD: biotechnology.
SUBSTANCE: group of inventions relates to biotechnology. Method for determining the presence or absence of an antibiotic and a method of determining the concentration of an antibiotic in a lactose-free sample are provided; kit and composition containing a lactose-free sample, a microorganism, a gelling agent, an indicator and one of milk and milk powder, for antibiotic determination in wastes; using bromocresol purple or bromothymol blue and using a compound which destructs β-lactams to determine the concentration of the antibiotic in the lactose-free sample. Methods envisage bringing a lactose-free sample, an analytical medium containing a microorganism, a gelling agent and an indicator capable of detecting growth or suppressing growth of the microorganism, and milk and/or milk powder in contact with each other. Obtained composition is incubated and the growth or inhibition of growth of the microorganism is detected using an indicator. Kit contains an analysis system and a guide for determining the antibiotic presence in wastes.
EFFECT: inventions provide antibiotic determination in wastes.
20 cl, 3 ex
