SRB FAST TEST
The SRB Fast Test has been designed for a quick and easy detection sulfate reducing bacteria. This test is very useful when there is not a lot of sample to work with (for example: water dripping from a pipe, signs of rust from a metallic or concrete structure, among others), or when the conditions are not the best for a more elaborated test. The SRB Fast Test has all the same nutrients and color-change indicators as regular API, but it also contains agar which makes it solid. The proper way to use this media is by using a cotton swab dipped in a potential bacterial sample and inserting it into the solid media. The media will start turning black if sulfate reducing bacteria are present, and in less than 24 hours the media will provide an answer to whether or not there are sulfate reducing bacteria in the sample.
Frequently Asked Questions
1-Can I use this media to find out an approximated concentration of bacteria in my sample?
No, sadly this media cannot be used for serial dilutions due to its solid nature. It can only provide a quick answer of whether or not there are sulfate reducing bacteria in a given sample. If there is a need to quantify or approximate bacterial concentrations, it is always better to use API or MPB media and perform serial dilutions.
2- How should I store this media?
The best way to maintain this media viable for a longer period of time is by keeping it refrigerated (4°C). Due to its solid nature, it can also remain stable at room nature for a prolonged period of time, however, if the media is left unattended inside a truck or in a warehouse for days, it could to start degrading and losing its consistency.
3- What could be considered as false positive or contamination?
For this media, a false positive occurs when the media turns black as soon as the cotton swab is inserted. This proves that the sample contains a high concentration of H2S, but it’ll be very hard to determine whether or not it was caused due to bacterial activity. It is very important to remember that SRB will grow at the bottom of the vial due to their anaerobic nature, so the color diffusion should begin mainly at the bottom and around the cotton swab. Contaminants could potentially grow in this media due to its nutritious nature, but the media will not turn black.