Performance of cocultivation of Chlorella vulgaris and four different fungi in biogas slurry purification and biogas upgrading by induction of strigolactone (GR24) and endophytic bacteria

Abstract

This study aimed to determine the best fungi to form the algal-bacterial-fungal symbionts and identify the optimal conditions for the synchronous processing of biogas slurry and biogas. Chlorella vulgaris (C. vulgaris) and endophytic bacteria (S395-2) isolated from it, and four different fungi (Ganoderma lucidum, Pleurotus ostreatus, Pleurotus geesteranus, and Pleurotus corucopiae) were used to form different symbiotic systems. Four different concentrations of GR24 were added to systems to examine the growth characteristics, the content of chlorophyll a (CHL-a), the activity of carbonic anhydrase (CA), the photosynthetic performance, the removal of nutrients, and the biogas purification performance. The results suggested that the growth rate, CA, CHL-a content, and photosynthetic performance of the C. vulgaris-endophytic bacteria-Ganoderma lucidum symbionts were higher than the other three symbiotic systems when 10 À9 M GR24 was added. The highest nutrients/CO 2 removal efficiency 78.36 ± 6.98% for chemical oxygen demand (COD), 81.63 ± 7.35% for total nitrogen (TN), 84.05 ± 7.16% for total phosphorus (TP), and 65.18 ± 6.12% for CO 2 was obtained under the above optimal conditions. This approach will provide a theoretical basis for the selection and optimization of the algal-bacterial-fungal symbionts for biogas slurry and biogas purification. Practitioner Points• Algae-bacteria/fungal symbiont presents superior nutrients and CO2 removal capacities.• The maximum CO2 removal efficiency was 65.18 ± 6.12%.• The removal performance was affected by fungi type.

Novel Strigolactone Mimics That Modulate Photosynthesis and Biomass Accumulation in Chlorella sorokiniana

“…Previous studies demonstrated the effects of the strigolactones analog GR24 [64,66,119] and of a natural strigolactone, 5-deoxystrigol [63], i.e., molecules that include A, B, C, and D rings, on microalgae,. The present study demonstrates, for the first time to the best of our knowledge, that strigolactone mimics, retaining only the butenolide D ring, are also active on microalgae.…”