Effect of different microalga-based technologies on biogas upgrading and nutrient removal by induction with strigolactone and endophytic bacteria

Abstract

The effective purification of digestate and biogas by four kinds of microalga-fungi-bacteria consortia had been studied to explore the optimal species of fungi under the stimulation of strigolactone analogs (GR24). Results showed that the purification effect of digestate and biogas was affected by fungal species, which was also positively correlated with the growth and photosynthetic performance of consortia. The consortium Chlorella sp.-Ganoderma lucidum-endophytic bacteria (S395-2) obtained the best growth and photosynthetic performance with chlorophyll a content, carbonic anhydrase, growth rate and average daily product rate of 199.64 ± 15.27 μg·L−1, 39.51 ± 2.15 units, 0.391 ± 0.04 day−1 and 0.0.304 ± 0.014 g·L−1·day−1, respectively. Moreover, the highest removal rates of chemical oxygen demand, total nitrogen, total phosphorus in digestate and CO2 in biogas were achieved by Chlorella sp.-Ganoderma lucidum-S395-2 treatment, which were 87.12 ± 7.21 %, 89.95 ± 8.24 %, 87.29 ± 8.24 %, 76.39 ± 6.38 %, respectively.