#Gelatin hydrolysis test download

(Janie Sigmon, York Technical College, Rock Hill, SC).įigure 6: Positive and Negative Gelatinase Activity Produced by Serratia marcescens and Micrococcus roseus (Labeled view) (Janie Sigmon, York Technical College, Rock Hill, SC). The gelatin in tube B is still solid which indicates no gelatinase produced by Micrococcus roseus. Note the liquification of the gelatin in tube A by Serratia marcescens which indicates the presence of the enzyme gelatinase. Both tubes were incubated at 25☌ for 24 hours followed by refrigeration for 30 minutes. Tube A was inoculated with Serratia marcescens and tube B was inoculated with Micrococcus roseus. Gelatin (BD Difco) was inoculated using the stab technique and an inoculating needle. Sturm, Cabrillo College, Aptos, CA).įigure 5: Positive and Negative Gelatinase Activity Produced by Serratia marcescens and Micrococcus roseus. Note: red color in the agar is pigment produced by Serratia marcescens. The Escherichia coli culture exhibited solidified agar after icing, indicating that gelatinase was not produced. The agar in the Pseudomonas aeruginosa and Serratia marcescens tubes remained liquid after incubation and icing, indicating digestion of gelatin by the exoenzyme gelatinase. Pseudomonas aeruginosa (top), Escherichia coli (middle), and Serratia marcescens (bottom) were inoculated into gelatin agar and incubated for 1 week. Biochemical Test and Identification of Klebsiella pneumoniae. (Anne Hanson, University of Maine, Orono, ME).įigure 4: Gelatinase. Inoculated culture plates were incubated for 24 hours.

Negative gelatin hydrolysis exhibited by Escherichia coli (B) is indicated by the absence of a clearing zone around the colony. Positive gelatin hydrolysis exhibited by Bacillus subtilis (A) is indicated by the clear zone around the colony after the addition of saturated ammonium sulfate. Gelatin hydrolysis test using the nutrient gelatin plate method. Torres, University of Santo Tomas, Manila, Philippines).įigure 3: Gelatin hydrolysis test. (Thomas Edison dela Cruz and Jeremy Martin O. After 30 minutes in an ice bath, the uninoculated control remained solid. Torres, University of Santo Tomas, Manila, Philippines).įigure 2: Gelatin hydrolysis test. Gelatin hydrolysis was observed after 3 days of incubation. After 30 minutes in an ice bath, the nutrient gelatin tube inoculated with Bacillus subtilis exhibited positive gelatin hydrolysis as shown by medium liquefaction.

#Gelatin hydrolysis test download

Download the PowerPoint PowerPoint Contentsįigure 1: Gelatin hydrolysis test.