Photofermentation

Photofermentation is the fermentative conversion of organic substrate to biohydrogen manifested by a diverse group of photosynthetic bacteria by a series of biochemical reactions involving three steps similar to anaerobic conversion. Photofermentation differs from dark fermentation because it only proceeds in the presence of light.

For example, photo-fermentation with Rhodobacter sphaeroides SH2C (or many other purple non-sulfur bacteria) can be employed to convert small molecular fatty acids into hydrogen and other products. Recently the production of ethanol fuels from green algae Chlamydomonas reinharddtii has also been considered as a promising alternatives.