Complex sentence: Dark fermentation is the fermentative conversion of organic substrate to biohydrogen, it is a complex process manifested by diverse group of bacteria by a series of biochemical reactions involving three steps similar to anaerobic conversion.
Split into simpler sentences: Dark fermentation is the fermentative conversion of organic substrate to biohydrogen. It is a complex process manifested by diverse group of bacteria by a series of biochemical reactions involving three steps similar to anaerobic conversion.