25 Jan 2012
It goes without saying that space travel is fraught with danger, astronauts face numerous health challenges during long durations in space, including diminished immunity, bone loss and an increased risk of radiation-induced carcinogenesis. A group of Canadian scientists, from the Canadian Space Agency and the Institut Rosell-Lallemand amongst others, believe that changes in the intestinal microbiota of astronauts may also contribute to these problems. Previous studies have also shown that the gut microbiota of astronauts prior to and post space missions are different in composition (Goncharonova, 1981). To counter this, scientists have suggested that the inclusion of probiotics, in soy-based fermented food products, could provide a nutritional strategy to help alleviate these health challenges. The scientists selected soy as it could provide a base for lactic acid bacteria as well as providing the benefits of soy isoflavones.
Strain selection tests were carried out to determine which probiotic strains grew and fermented most effectively in soy milk - L. acidophilus Rosell-52, B. longum Rosell-175 and S. thermophilus ST5. Further in vitro tests were then performed to assess the three strains ability to down-regulate the production of the pro-inflammatory agents in the gut.
The results of the test suggested that probiotic bacteria can be successfully utilised to develop soy-based fermented products, targeted specifically for long-term space travel. The researchers concluded, "The spectrum of health benefits associated with probiotics will likely not be found in a single bacterium...in this study, we found that the B. longum Rosell-175 could contribute to gas reduction; the lactobacilli are linked to bone metabolism and immune enhancement."
Reference: Buckley, N. D et al. (2010) Harnessing functional food strategies for the health challenges of space travel - Fermented soy for astronaut nutrition. Acta Astronautica, 68, pp. 731-738
Goncharonova, G. I et al. (1981) Bifidobacterium flora status of cosmonauts before and after completing space flights. Moscow Kosmicheskaya biologiya I aviakosmicheskaya meditsina. 15, pp. 14-18.