## 3 Results
### Effect of Joint Presence of PFCs and OPCs on Consortia of Bacterial and Microalgae Cells
The maximum ATP values corresponded to the combination of \"microalgae:bacteria\" at a ratio of 25:1, which, apparently, provides for the formation of a consortium with intercellular interaction of cultures. The combination of microalgae with a bacterial consortium was expected to increase the rate of accumulation of phototrophic biomass. It was possible to accumulate the maximum amount of microalgae biomass in 3 days in the medium when the ratio between participants of the microbial combination \"microalgae:bacteria\" was 25:1. The presence of a PFC in the medium, as before, had a positive effect on the rate of accumulation of microalgae biomass. It was noted that, unlike individual cultures, when microalgae were combined with bacteria, there was no decrease in ATP concentration in the presence of PFCs as compared to the control (Tables 1 and 2). Perhaps this effect was due to the formation of mutualistic relations between the participants in microbial societies, manifested in bacterial and microalgal synergy for removing xenobiotics and environmental toxicity. Probably, AHLs synthesized by bacteria contributed to the enhancement of the photoautotrophic growth of _C. vulgaris_ cells, which is generally consistent with the literature data [57]. Evaluation of the intensity of photobacteria bioluminescence after their exposure in culture media containing 0.15 mM methyl parathion and different concentrations of PFCs (Table 3) showed that changes in the residual bioluminescence of cells during the first 24 h already indicated a tendency toward decreasing toxicity in the media. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Studied Parameter**} & \multicolumn{6}{c}{**Biomass Ratio \({}^{\prime\prime}\)Microalgae:Bacteria”**} \\ \cline{2-7}  & **6:1** & **12:1** & **25:1** & **6:1** & **12:1** & **25:1** \\ \cline{2-7}  & \multicolumn{6}{c}{**Perfluorohexane**} & \multicolumn{6}{c}{**Polyether II**} \\ \hline  & \multicolumn{6}{c}{**0\% \(v/v\)**} \\ \hline ATP\({}_{\text{in\,granules}}\) (mmol/g) & 0.4 \(\pm\) 0.0 & 0.8 \(\pm\) 0.0 & 15.2 \(\pm\) 0.7 & 0.4 \(\pm\) 0.0 & 0.8 \(\pm\) 0.0 & 15.2 \(\pm\) 0.7 \\ ATP\({}_{\text{in\,medium}}\) (mmol/mL) & 33 \(\pm\) 0.1 & 37 \(\pm\) 1 & 80 \(\pm\) 3 & 33 \(\pm\) 0.1 & 37 \(\pm\) 1 & 80 \(\pm\) 3 \\ The average rate of biomass accumulation (g DCW/L/d) & 0.25 \(\pm\) 0.0 & 0.35 \(\pm\) 0.0 & 0.41 \(\pm\) 0.0 & 0.25 \(\pm\) 0.0 & 0.35 \(\pm\) 0.0 & 0.41 \(\pm\) 0.0 \\ \hline  & \multicolumn{6}{c}{**0.5\% \(v/v\)**} \\ \hline ATP\({}_{\text{in\,granules}}\) (mmol/g) \({}^{\star}\) & 0.8 \(\pm\) 0.0 & 4.3 \(\pm\) 0.2 & 17.7 \(\pm\) 0.9 & 0.8 \(\pm\) 0.0 & 4.32 \(\pm\) 0.21 & 17.7 \(\pm\) 0.9 \\ ATP\({}_{\text{in\,medium}}\) (mmol/mL) & 34 \(\pm\) 1 & 38 \(\pm\) 1 & 87 \(\pm\) 4 & 35 \(\pm\) 1 & 38 \(\pm\) 1 & 88 \(\pm\) 4 \\ The average rate of biomass accumulation (g DCW/L/d) & 0.32 \(\pm\) 0.01 & 0.36 \(\pm\) 0.01 & 0.44 \(\pm\) 0.02 & 0.3 \(\pm\) 0.01 & 0.35 \(\pm\) 0.01 & 0.48 \(\pm\) 0.02 \\ \hline  & \multicolumn{6}{c}{**1\% \(v/v\)**} \\ \hline ATP\({}_{\text{in\,granules}}\) (mmol/g) \({}^{\star}\) & 1.5 \(\pm\) 0.1 & 2.5 \(\pm\) 0.1 & 19.8 \(\pm\) 0.9 & 1.6 \(\pm\) 0.1 & 2.5 \(\pm\) 0.11 & 22.7 \(\pm\) 0.8 \\ ATP\({}_{\text{in\,medium}}\) (mmol/mL) & 34 \(\pm\) 1 & 38 \(\pm\) 1 & 89 \(\pm\) 4 & 35 \(\pm\) 1 & 40 \(\pm\) 2 & 90 \(\pm\) 4 \\ The average rate of biomass accumulation (g DCW/L/d) & 0.36 \(\pm\) 0.01 & 0.38 \(\pm\) 0.01 & 0.53 \(\pm\) 0.02 & 0.37 \(\pm\) 0.01 & 0.37 \(\pm\) 0.01 & 0.54 \(\pm\) 0.02 \\ \hline  & \multicolumn{6}{c}{**1\% \(v/v\)**} \\ \hline ATP\({}_{\text{in\,granules}}\) (mmol/g) \({}^{\star}\) & 1. After 72 h of cultivation, the residual bioluminescenceence of photobacteria was almost 100%. This is explained by the fact of complete decomposition of methyl parathion and the utilization by cells of its biodegradation products. As for PFCs, they can be partially utilized by _P.