Encapsulation of the therapeutic microbe Akkermansia muciniphila in a double emulsion enhances survival in simulated gastric conditions

Abstract

There is considerable attention for developing Akkermansia muciniphila as a new therapeutic microbe since it has shown to prevent diet-induced obesity and type 2 diabetes in mice. However, A. muciniphila is sensitive to gastric conditions such as low pH and oxygen. Therefore, we explored the possibility of encapsulating A. muciniphila in a water-in-oil-in-water (W/O/W) double emulsion, to allow for protection during gastric passage and subsequent release in the small intestine. The bacteria were efficiently encapsulated in the inner emulsion droplets and remained entrapped during in vitro gastric digestion. The cells were then released in the simulated intestinal phase of the in vitro system. The viability of encapsulated cells was found to be higher when compared to cells dispersed in buffer, that had been subjected to similar mechanical process as the one conducted to prepare the emulsion systems. Surprisingly, the viability of the processed cells was even higher than that of the cells dispersed in buffer without processing, likely due to shear-induced stress tolerance. To conclude, encapsulation in a double emulsion seems to be a promising strategy to protect A. muciniphila during gastric passage in oral formulations.

Keywords: Akkermansia muciniphila; Double emulsion; Gastric conditions; Gut bacteria; Therapeutic microbe.