Add Samples: skin (122.3 mg) and spleen tissues (38.6 mg).
For Bacteria culture: S. pyogenes was grown in Todd Hewitt Broth supplemented with 1% yeast extract at 37°C un til an A600 = 0.5.
Buffer: 0.7% sterile saline (1000μl) inoculated with S.pyogenes (T0 Inoculum). Note that pathogenic S. pyogenes must be processed under appropriate biosafety containment.
Run the Precellys for Spleen at 6000 rpm, 1x30 sec, and for Skin at 6000 rpm, 2x30 sec or 6000 rpm, 4x30 sec.
Following tissue homogenization, the number of viable bacterial cells (CFU/ml) present was determined by serial dilution in sterile 0.7% saline and plating onto nutrient agar. Results indicate that for all treatment groups the type of bead and the processing time had no significant effect on the viability of S. pyogenes (t test p> 0.1)
The effect of tissue homogenization on the viability of S. pyogenes. Data represents the mean CFU/ml from triplicate samples with error bars indicating the standard derivation. The inoculum represents the CFU/ml added to each sample.