## Materials and Methods
### Bacterial Consortium Selection
#### 2.9.1 ACC Deaminase Activity  
The ACC deaminase enzyme converts ACC into \(\alpha\)-ketobutyrate (\(\alpha\)-KB) and ammonium. The bacterial strains of selected consortia were analyzed to determine their ability to grow in culture medium with ACC as the sole nitrogen (N) source, according to the procedures described by [PERSON] [58] and [PERSON] et al. [42]. Selected bacteria were grown in TSB medium for \(\sim\)12 h at 30 \({}^{\circ}\)C. The bacterial cells were washed two times with saline solution (NaCl 0.85\(\%\)\(w\)\(v^{-1}\)) and centrifuged at 8000\(\times\)\(g\) for 10 min at 4 \({}^{\circ}\)C. A volume of 500 \(\mu\)L of the culture was resuspended in saline solution and incorporated in 4.5 mL of DF (Dworkin and Foster) medium (4 g L\({}^{-1}\) KH\({}_{2}\)PO\({}_{4}\), 6 g L\({}^{-1}\) Na\({}_{2}\)HPO\({}_{4}\), 0.2 g L\({}^{-1}\) MgSO\({}_{4}\)\(\times\) 7H\({}_{2}\)O, 2 g L\({}^{-1}\) gluconic acid, 2 g L\({}^{-1}\) citric acid, and 1 mL trace elements containing 0.001 g L\({}^{-1}\) FeSO\({}_{4}\)\(\times\) 7H\({}_{2}\)O, 0.01 g L\({}^{-1}\) H\({}_{3}\)BO\({}_{3}\), 0.011 g L\({}^{-1}\) MnSO\({}_{4}\)\(\times\) H\({}_{2}\)O, 0.125 g L\({}^{-1}\) ZnSO\({}_{4}\)\(\times\) 7H\({}_{2}\)O, 0.078 g L\({}^{-1}\) CuSO\({}_{4}\)\(\times\) 5H\({}_{2}\)O, 0.01 g L\({}^{-1}\) MoO\({}_{3}\); with (NH\({}_{4}\))\({}_{2}\)SO\({}_{4}\) (2 g L\({}^{-1}\)) as sole N source and glucose (2 g L\({}^{-1}\)) as the carbon source) for 1-2 days at 30 \({}^{\circ}\)C. The bacterial cells were washed three times with saline solution and centrifuged at 8000\(\times\)\(g\) for 10 min at 4 \({}^{\circ}\)C. The bacterial pellets were resuspended in 1 mL of saline solution and 100 \(\mu\)L of each inoculum were incorporated in 3 mL of DF medium with 3 mM ACC as sole N source and glucose as carbon source, in triplicate. Growth was evaluated for 5 days at 30 \({}^{\circ}\)C.  
The ACC deaminase activity was determined by measuring \(\mu\)moles \(\alpha\)-KB mg protein\({}^{-1}\) h\({}^{-1}\) produced in the assays. The procedure described was carried out again for bacteria with positive growth in ACC, to evaluate ACC deaminase activity. A volume of 250 \(\mu\)L of inoculum was incorporated into 7.5 mL of DF medium with 3 mM ACC as sole nitrogen source and glucose as carbon source. On the fourth day, the cells were washed two times with saline solution and centrifuged at 8000\(\times\)\(g\) for 10 min at 4 \({}^{\circ}\)C. Bacteria pellets were resuspended in 1 mL of 0.1 M Tris-HCl pH 7.6 and centrifuged at 16,000\(\times\)\(g\) for 5 min, the supernatant was removed, and the pellet was resuspended in 600 \(\mu\)L of 0.1 M Tris-HCl pH 8.5. A volume of 30 \(\mu\)L of toluene was added and stirred for 30 s, and a volume of 100 \(\mu\)L was used to measure the protein concentration by Bradford method [41]. A volume of 200 \(\mu\)L (in duplicate) was placed in a new centrifuge tube, 20 \(\mu\)L of 0.5 M ACC was added, shaken briefly, and incubated for 15 min at 30 \({}^{\circ}\)C. A volume of 1 mL of 0.56 M HCl was added, it was stirred and centrifuged for 5 min at 16,000\(\times\)\(g\) at room temperature. A volume of 1 mL of supernatant was taken, 800 \(\mu\)L of 0.56 M HCl was added, stirred, and placed in glass tubes to later incorporate 300 \(\mu\)L of 2,4-dinitrophenylhydrazine (0.2% 2,4-dinitrophenylhydrazine in 2 M HCl), stirred and incubated at 30 \({}^{\circ}\)C for 30 min. A volume of 2 mL of 2 N NaOH was added and it was stirred. Then, the absorbance at 540 nm was measured on a Multiskan GO spectrophotometer (Thermo Fisher Scientific, Waltham, MA, USA). A standard curve of \(\alpha\)-KB from 0 to 2 mM was performed. The \(\mu\)moles \(\alpha\)-KB mg protein\({}^{-1}\) h\({}^{-1}\) were calculated according to the values of \(\alpha\)-KB and the protein concentration (mg mL\({}^{-1}\)) after an incubation of 15 min.