Biochemical identification of unknown bacteria Lab Report

Biochemical identification of unknown bacteria - Lab Report Example 1) Nutrient agar slant: Given culture was streak on the nutrient agar slant and incubated at two different temperature 25Â °C and 37Â °C respectively. After 24h of incubation, slants were taken out from incubator and growth was observed. Growth on tube incubated at 37Â °C was found to be effuse and the growth was extensive while in case of tube incubated at 25Â °C growth was found to be lesser compared to previous tube and echinulated in nature. There was no pigmentation observed and growth was found to be whitish in color and translucent in nature. Results indicated that given unknown bacteria is either Escherichia coli, Enterobacter aerogenes or Staphylococcus aureus ,being human /animal inhabitant The optimum temperature for growth of these bacteria is 37Â °C (i.e. human body temperature) while in case of Pseudomonas aerogenosa being free living as well as human inhabitant, it can grow at 25Â °C as well as 37Â °C . Similarly it also produces bluish green pigment and grows as mucoid colony. 2) Nutrient agar: Given culture was streak on to the nutrient agar plate using quadrant streak technique and incubated at 37Â °C for 24 h. After incubation colonies were found to be convex, circular and having entire margin. Optically colonies were found to be translucent and without any pigmentation. This observation again ruled out the possibility of Pseudomonas aeroginosa. Similarly colony of Staphylococcus aureus is opaque, slightly elevated, appears yellowish white.