Mixotrophic and heterotrophic growth of some microalgae using extract of fungal-treated wheat bran

Background: In this study, wheat bran, an agricultural waste, was utilized as a low-cost carbon source for algal cultivation. Results: Treatment of lignocellulosic waste by two fungal species (Pleurotus ostreatus or Trichoderma viride) caused the accumulation of reducing sugar at a relatively high concentration (50.58 and 54.30 mg/g wheat bran) after 7 days of incubation, respectively. The soluble products of treated wheat bran increased the growth, carbohydrate, and protein contents of both Chlorella vulgaris and Scenedesmus obliquus under mixotrophic and heterotrophic conditions. Conclusions: The obtained data suggest that soluble product of treated wheat bran could be used as an efficient medium for the mixotrophic and heterotrophic growth of both algal species.