In her book Gut and Psychology Syndrome , Dr. Natasha Campbell-McBride lists six families of probiotic microbes. The following summary is excerpted from p. 247-249. (I heartily recommend reading her book for a more complete look at health and the gut lining.)
One important note regarding probiotics in supplement or food form: It is best to start small. Introducing probiotic bacteria can result in a die-off response as the pathogens die and release toxins. This can manifest in a skin rash, extreme fatigue, fever, sore throat, or a variety of other symptoms.
Fermented foods offer a wonderful source of natural probiotics. In upcoming posts I will detail the benefits of Efficient Microorganisms, or EMs. EMs offer a combination of beneficial bacteria, yeasts, and soil bacteria. (Pictured here in my kitchen.)
Water and dairy kefir offer a combination of beneficial yeasts and bacteria. Yogurt provides lactic acid bacteria in abundance, as do sauerkraut and kimchi. See the momsAWARE Natural Year Challenge: Food Edition to learn more about making your own fermented foods.