Saccharomyces cerevisiae var. boulardii – Probiotic Yeast

The discovery and study of the budding yeast Saccharomyces cerevisiae var. boulardii (Sb) is strictly related to the concept of health promoting microorganisms from food. The first most well-known and popularized throughout Europe assumption of health promoting food containing living microorganisms was yogurt. Appointed in 1888 by Louis Pasteur, Ilya Ilyich Metchnikov working in Paris developed a theory that aging is caused by toxic bacteria in the gut and that lactic acid could prolong life which resulted in popularization of yogurt consumption. Metchnikov received with Paul Ehrlich the Nobel Prize in Medicine in 1908 for his previous work on phagocytosis, which probably promoted his idea of today’s so called functional food further and triggered subsequent research on this subject. Scientists started to look for traditional, regional food products considered good for health. One of them was French scientist Henri Boulard who was in IndoChina in 1920 during cholera outbreak. He observed that some people chewing the skin of lychee and mangosteen or preparing special tea did not develop the symptoms of cholera. This observation lead Henri Boulard to the isolation of a tropical strain of yeast named Saccharomyces boulardii (Sb) from lychee and mangosteen fruit, which is nowadays the only commercialized probiotic yeast.