This invention relates to a bioreactor, more particularly to a tubular photo bioreactor (TPB), which is capable of stimulating plant growth, especially micro algal growth. The tubular photo bioreactor includes a reservoir for holding a liquid containing plant material, wherein the reservoir is devoid from light, a pump in fluid communication with the reservoir and a length of transparent tube extending from the pump to the reservoir through which the liquid can be circulated. The tubular photo bioreactor further includes a frame adapted to support the tube extending between the pump and the reservoir in a coiled formation about the frame in an illuminated environment illuminated by natural light and/or artificial light. In this manner, the liquid is capable of being circulated by the pump between a dark phase, wherein the liquid passes through the dark reservoir, and a light phase, wherein the liquid is exposed to light as it passes through the tube in the illuminated environment, such that the growth of the plant material in the liquid is stimulated by the dark and light phase cycle.
