The researchers studied the blood microbiota of healthy individuals using a new method to see which bacteria and fungi could be grown in a lab. They found that certain bacteria and fungi were easier to grow than others, and identified specific groups that were more likely to be cultured. The study showed that a high concentration of vitamin K in the medium helped with culturing. This research helps us understand more about the types of microbes present in our blood and how they can be studied in the lab.