Valorization of Spent Escherichia coli Media Using Green Microalgae Chlamydomonas reinhardtii and Feedstock Production

Abstract

The coupling of Chlamydomonas reinhardtii biomass production for nutrients removal of Escherichia coli anaerobic broth (EAB) is thought to be an economically feasible option for the cultivation of microalgae. The feasibility of growing microalgae in using EAB high in nutrients for the production of more biomass was examined. EAB comprised of nutrient-abundant effluents, which can be used to produce microalgae biomass and remove environment pollutant simultaneously. In this study, C. reinhardtii 21gr (cc1690) was cultivated in different diluted E. coli anaerobic broth supplemented with trace elements under mixotrophic and heterotrophic conditions. The results showed that C. reinhardtii grown in 1×, 1/2×, 1/5× and 1/10×E. coli anaerobic broth under mixotrophic conditions exhibited specific growth rates of 2.71, 2.68, 1.45, and 1.13 day-1, and biomass production of 201.9, 184.2, 175.5, and 163.8 mg L-1, respectively. Under heterotrophic conditions, the specific growth rates were 1.80, 1.86, 1.75, and 1.02 day-1, and biomass production were 45.6, 29.4, 15.8, and 12.1 mg L-1, respectively. The removal efficiency of chemical oxygen demand, total-nitrogen and total-phosphorus from 1×E. coli anaerobic broth was 21.51, 22.41, and 15.53%. Moreover, the dry biomass had relatively high carbohydrate (44.3%) and lipid content (18.7%). Therefore, this study provides an environmentally sustainable as well economical method for biomass production in promising model microalgae and subsequently paves the way for industrial use.

Evaluation of the effects of temperature, light, and UV-C radiation on HSP70A expression in Chlamydomonas reinhardtii

“…Molecular analysis of Chlamydomonas HSP genes, combined with photobiological studies on their expression, will provide information about the mechanisms of light regulating genes. In the study conducted, 40 µEm -2 s -1 and 23 °C as continuous light value, the values above was evaluated as high light intensity, and the values below was evaluated as low light intensity similar to recent studies (Mayfield and Schultz, 2004;Zhang et al, 2017). For light intensity studies, the cells were exposed to light stress between 0-140 µmol E.m -2 s -1 , for different periods (0 [control], 2, 6, 12, 24 h) and ARS activity was determined.…”

Improving Acetic Acid Production by Over-Expressing PQQ-ADH in Acetobacter pasteurianus

“…The sample was centrifuged at 25°C for 10 min at 10,000 × g, and 1 ml of the supernatant was diluted with distil-water and filtered through a 0.22 μm membrane. An Atlantis dC 18 150 mm × 4.6 mm (3.0 um) chromatographic column (Waters, USA) was used as analytical column with a flow rate of 0.6 ml min −1 , the column temperature was 30°C (Li et al, 2014 ; Qin et al, 2016 ; Zhang et al, 2017 ). 0.05 M NH 4 H 2 PO 4 buffer adjusted to pH value 2.5 with phosphoric acid was conducted as mobile phase.…”