## 2 Materials and Methods
### Characterization of Liquid Digestate and Slurry  
Digestate and bovine slurry were collected at \"La Bouzule farm\" near Nancy, France. From the initial highly loaded effluents, and in order to avoid strong inhibition effects, diluted effluents were prepared to test the effect of dilution on our experiments. The diluted effluents, called \"Liquid Digestate 0 (DL\({}_{0}\))\" and \"Liquid Slurry 0 (SL\({}_{0}\))\", were obtained after filtration (coffee filters, \(\O\) pores \(\approx\) 20 \(\upmu\)m) of a mixture of 100 g of digestate or slurry in 1 L of distilled water, in order to eliminate most of the particles in the suspension \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multicolumn{1}{c}{**Flocs Biomass Ma-B**} & \multicolumn{1}{c}{**TSS**} & \multicolumn{1}{c}{**VSS**} & \multicolumn{1}{c}{**AI \({}^{*}\)**} & \multicolumn{1}{c}{**Chl (a)**} \\ \hline
**Unit** & **g TSS\(\cdot\)L\({}^{-1}\)** & **g VSS\(\cdot\)L\({}^{-1}\)** & **mg VSS\(\cdot\)mg\({}^{-1}\) Chl (a)** & **mgChl (a)\(\cdot\)g\({}^{-1}\) VSS** \\ \hline
**Batch Culture** & T\({}_{0}\) & 4.4 \(\pm\) 0.1 & 2.7 \(\pm\) 0.1 & 288.8 \(\pm\) 0.1 & 3.4 \(\pm\) 0.1 \\ T\({}_{7}\) & 4.6 \(\pm\) 0.2 & 2.8 \(\pm\) 0.2 & 220.8 \(\pm\) 0.2 & 4.5 \(\pm\) 0.2 \\ \hline \hline \end{tabular}  
* Autotrophic index represents the quotient between the values of VSS and chlorophyll (a) [21].  
\end{table} 
Table 1: Biomass characteristics of Ma-B flocs after batch culture. \begin{table}
\begin{tabular}{c c c c} \hline \hline \multicolumn{1}{c}{**Reagents**} & \multicolumn{1}{c}{**Reagent Grade**} & \multicolumn{1}{c}{**Concentrations**} \\ \multicolumn{1}{c}{(Merck-Sigma Aldrich)} & \multicolumn{1}{c}{**Reagent Grade**} & \multicolumn{1}{c}{**Concentrations**} \\ \hline Organic medium (O) & Glucose & \(\geq\)99.5\% & 600 mg COD.L\({}^{-1}\) & 50\% = 298.4 mg\(\cdot\)L\({}^{-1}\) \\ (1L) & Acetate & \(\geq\)95.0\% & 50\% = 603.3 mg\(\cdot\)L\({}^{-1}\) \\ \hline \multirow{4}{*}{Nutrient medium (N)} & N-NH\({}_{4}\) (NH\({}_{4}\)Cl) & \(\geq\)99.5\% & 100 mg\(\cdot\)L\({}^{-1}\) \\  & P-PO\({}_{4}\) (KH\({}_{2}\)PO\({}_{4}\)) & \(\geq\)99.0\% & 10 mg\(\cdot\)L\({}^{-1}\) \\ (1L) & Ca\({}^{2+}\) (CaCl\({}_{2}\)\(\cdot\)2H\({}_{2}\)O) & \(\geq\)93.0\% & 10 mg\(\cdot\)L\({}^{-1}\) \\  & Mg\({}^{2+}\) (MgSO\({}_{4}\)\(\cdot\)7H\({}_{2}\)O) & \(\geq\)99.5\% & 5 mg\(\cdot\)L\({}^{-1}\) \\  & Fe\({}^{2+}\) (FeSO\({}_{4}\)\(\cdot\)7H\({}_{2}\)O) & \(\geq\)99.0\% & 5 mg\(\cdot\)L\({}^{-1}\) \\ \hline \multirow{4}{*}{Trace elements} & H\({}_{3}\) BO\({}_{3}\) & \(\geq\)99.5\% & 50 mg\(\cdot\)L\({}^{-1}\) \\  & ZnCl\({}_{2}\) & \(\geq\)98.0\% & 50 mg\(\cdot\)L\({}^{-1}\) \\ \cline{1-1}  & CuCl\({}_{2}\) & \(\geq\)99.0\% & 30 mg\(\cdot\)L\({}^{-1}\) \\ \cline{1-1}  & MnSO\({}_{4}\)\(\cdot\)H\({}_{2}\)O & \(\geq\)99.0\% & 50 mg\(\cdot\)L\({}^{-1}\) \\ \cline{1-1}  & (NH\({}_{4}\))6 Mo\({}_{7}\)O\({}_{24}\)\(\cdot\)4H\({}_{2}\)O & \(\geq\)99.0\% & 50 mg\(\cdot\)L\({}^{-1}\) \\ \cline{1-1}  & AlCl\({}_{3}\) & \(\geq\)99.0\% & 50 mg\(\cdot\)L\({}^{-1}\) \\ \cline{1-1}  & CoCl\({}_{2}\)\(\cdot\)6H\({}_{2}\)O & \(\geq\)98.0\% & 50 mg\(\cdot\)L\({}^{-1}\) \\ \cline{1-1}  & NiCl\({}_{2}\) & \(\geq\)98.0\% & 50 mg\(\cdot\)L\({}^{-1}\) \\ \hline \hline \end{tabular}  
\end{table} 
Table 2: Composition of synthetic wastewater. that could limit/inhibit the biological kinetics of the microorganisms and their growth. The substrates were characterized to determine the concentrations of major nutrients in the form of **(i)** COD, **(ii)** total NH4-N, and **(iii)** P-PO4 using the methods adapted to a spectrophotometer type HACH DR 2400, (Germany). These methods' principles can be described as follows: **(i)** COD: The organic material is oxidized by a solution containing a known excess of potassium dichronate and mercury sulfate II (to eliminate interference from chloride ions). The reaction takes place in a strong acid medium (sulfuric acid with the addition of silver sulfate as a catalyst) and at reflux for 2h.