API test preparation

hi everyone i have problems in the inoculum preparation before i do the API test , when i apply the biomeriaux methodology the results are between 60 -70%  valid , does anyboby have an article  to support an alternative  way of inoculum preparation ?

What are you trying to identify? Which API test are you running? Did you use selective media? 

I would follow the following

raw sample>enrichment media>selective media>API test

API test do not always correctly identify enviromental bacteria (expression of atypical genes)

thanx for the answer i try to use the API 20E ( food matrix)and i have problem in making the correct inoculum to spike into the strip.The manual states that one should take enough colonies to create a macfarland Standard and then inject into the strips. My problem is that this particular procedure does not give satisfactory results   .Any alternatives ?

1. Is the sample from the environment or lab stock culture.

2. Using a 0.1 uL loop, a loop full (just one or 2 small size colony) and inoculate the 2 mL saline ampoule. Mix the saline and cell with the loop. I will also use a pasture pipette to uptake and evacuate the saline/cell solution 4 or 5 times to suspend the cells. It should look like #1 to #2 McFarland standard ( cloudy but not milky)

3. I would not incubate for more then 26 -28 hours, its important to read the strip at this time.

thnx i will  try to check it !!

According to the pack insert for the API 20e the inoculation should be by taking 1 colony and mixing it with the suspension medium.

Poor results are IMEX most often due to mixed cultures, so make sure you clean up your isolate well before testing.

I find it's best to take your colony from non-selective agar, making sure the colony is no more than hours old.

I dont use the McFarland standard. I just take a 1microlitre loop and fill it ( approx 3-5 colonies) and this will create a heavy enough inoculum.

It then has to be mixed really well to disperse clumps.