Abstract: The invention relates to a novel culture medium and a method for the identification of gram-negative microorganisms based on the differentiation of said microorganisms by the appearance of 10 different colors in the colonies, which may be regular or irregular, and halos of at least 5 different colors and sizes. Said medium comprises a mixture of components favoring the appearance of halos of different colors and sizes and consists of siliceous earth, skim milk, starches and activated carbon. The medium according to the invention also comprises a mixture of nutritional bases, substances ensuring the appearance of different colorations in the colonies, substances ensuring inhibition of gram-positive microorganisms and substances providing the necessary solid matrix for the growth and development of the colonies.

Abstract: The present invention is related with Microbiology and particularly with a nutrient mixture and a procedure for the identification and the early count of Gram-negative organisms. This mixture allows the development of five different colony colors in the organisms to be detected, and the appearance of three colored fluorescent emissions, the appearance of three different colors halos and zones with opaque precipitates surrounding such colonies. Those factors, together with the color changes in the medium, allow a differentiation with a high sensibility and specificity level.

Abstract: The present invention is related with the Microbiology field and particularly with a composition and a method for early detection, identification, differentiation and count of microscopic organisms, concretely Gram-negative microorganisms.