A1. Test items for conditions on biofilm formation include types of culture media, seeding density of microorganisms, frequency of media changes, incubation time, incubation temperature, and others.We show examples of optimizing the following test items: types of culture media, seeding density of microorganisms, frequency of media changes, and incubation time, as below.If you optimize incubation temperature, it is necessary to use a number of the Biofilm Formation Assay Kits (Product code: B601).
Measure the amount of biofilm formation – ①Under the following optimized conditions: types of culture media, seeding density of microorganisms, and media changes, the amount of biofilm formation can be confirmed by the experiments shown below.
Example of plate arrangement
Experimental schedule
Procedure(Step 1) Day 1: 96-well plate ①In accordance with the reference layout shown above, fill each well (rows A and B) of the 96-well plate with 180μl of microbial cell suspension with concentrations ① and ② made in culture media A through D.Leave the wells (rows C through H) blank. Place a 96-peg lid on the 96-well plate and incubate the plate at the optimum growth temperature for the microorganism for 24 hours.※ ExamplesMicrobial concentrations ① and ②: Approximately 107 CFU/ml and 106 CFU/ml, respectively.(Step 2) Day 2: 96-well ②In accordance with the reference layout shown above, fill each well (rows A and B) of the 96-well plate with 180μl of culture media without microorganism.Fill each well (rows C and D) of the same 96-well plate with 180μl of microbial cell suspension with concentrations ① and ② made in culture media A through D. Leave the wells (rows E through H) blank.Place the 96-peg lid (Step1) on the 96-well plate ② and incubate the 96-well plate ② at the optimum growth temperature for the microorganism for 24 hours.(Step 3) Day 3: 96-well plate ③In accordance with the reference layout shown above, fill each well (rows A through D) of the 96-well plate with 180μl of culture media without microorganism.Fill each well (rows E and F) of the same 96-well plate with 180 μl of microbial cell suspension with concentrations ① and ② made in culture media A through D. Leave the wells (rows G and H) blank.Place the 96-peg lid (Step1) on the 96-well plate ③ and incubate the 96-well plate at the optimum growth temperature for the microorganism for 24 hours.(Step 4) Day 4: 96-well plate ④In accordance with the reference layout shown above, fill each well (rows A through F) of the 96-well plate with 180μl of culture media without microorganism.Fill each well (rows G and H) of the same 96-well plate with 180μl of microbial cell suspension with concentrations ① and ② made in culture media A through D.Place the 96-peg lid (Step1) on the 96-well plate ④ and incubate the 96-well plate ④ at the optimum growth temperature for the microorganism for 24 hours.(Step5) Perform experiments using a new 96-well plate, in accordance with Steps 2 through 6 which describe the measurements of biofilm formation/inhibition of biofilm formation in the technical manual.Measure the amount of biofilm formation – ②Under the following optimized conditions: types of culture media, seeding density of microorganisms, and media changes, the amount of biofilm formation can be confirmed by the experiments shown below.
Example of plate arrangement
Experimental schedule
Procedure(Step 1) Day 1: 96-well plate○1In accordance with the reference layout shown above, fill each well (rows A and B) of the 96-well plate with 180μl of microbial cell suspension with concentrations ① and ② made in culture media A through D.Leave the wells (rows C through H) blank.Place a 96-peg lid on the 96-well plate and incubate the plate at the optimum growth temperature for the microorganism for 24 hours.※ ExamplesMicrobial concentrations ① and ②: Approximately 107 CFU/ml and 106 CFU/ml, respectively.(Step2) Day 2: Remove the 96-peg lid. Allow cells to grow in the rows A and B of the 96-well plate○1 without changing the culture medium.Fill each well (rows C and D) of the same 96-well plate with 180μl of microbial cell suspension with concentrations ① and ② made in culture media A through D. Leave the wells (rows E through H) blank.Place the 96-peg lid back to the 96-well plate ①. Continuously incubate the 96-well plate ① at the optimum growth temperature for the microorganism for 24 hours.(Step3) Day 3: Remove the 96-peg lid. Allow cells to grow in the rows (A through D) of the 96-well plate ①without changing the culture medium.Fill each well (rows E and F) of the same 96-well plate with 180μl of microbial cell suspension with concentrations ① and ② made in culture media A through D. Leave the wells (rows G and H) blank. Place the 96-peg lid back to the 96-well plate ①. Continuously incubate the 96-well plate ① at the optimum growth temperature for the microorganism for 24 hours.(Step 4) Day 4: Remove the 96-peg lid. Allow cells to grow in the rows (A through F) of the 96-well plate ① without changing the culture medium.Fill each well (rows G and H) of the same 96-well plate with 180 μl of microbial cell suspension with concentrations ① and ② made in culture media A through D. Leave the wells (rows G and H) blank. Place the 96-peg lid back to the 96-well plate ①. Continuously incubate the 96-well plate ① at the optimum growth temperature for the microorganism for 24 hours.(Step 5): Perform experiments using a new 96-well plate, in accordance with Steps 2 through 6 which describe the measurements of biofilm formation/inhibition of biofilm formation in the technical manual.