## 4 Discussion  
After isolating some microbial strains from a natural community, targeted experiments can be performed to highlight optimal community compositions that are responsible for the production of specific metabolites through specific biochemical interactions [29]. In this work, we applied this concept to isolate three strains, i.e., _R. oryzae_, _S. cerevisiae_ and _L. plantarum_, from a natural community used in Cambodian fermentation starter in order to determine the performances of synthetic communities by comparison with the natural one. Indeed, microbial composition has a strong impact on both rice wine quality and yield. Basically, spontaneous cereal-based fermentation involves complex interf kingdom microbial consortia, including fungi, yeasts, and lactic acid bacteria [2; 13]. _R. oryzae_ has been reported as a strong amylase enzyme producer, frequently found in amyloidytic fermentation starters for rice wine and during saccharification [4; 7; 9; 30; 31]. _R. oryzae_ produces amylase hydrolyzing starch into fermentable sugar feeding _S. cerevisiae_ and _L. plantarum_ (Figure 4A). The presence of LAB found in cereal fermentation is important because beside producing lactic acid, LAB is likely to contribute to the production of some flavor compounds and to display some specific metabolic cross-feeding with yeast [32]. The growth of _S. cerevisiae_ in fermented food is induced by acidification from bacteria and it adjusts its metabolism by secreting a serial metabolite, notably an amino acid, allowing the survival of LAB (Figure 4A) [33; 34]. The result of this study supports this evidence, with both _L. plantarum_ and _S. cerevisiae_ promoting the growth of each other during the first 24 hours when grown in co-culture. \begin{table}
\begin{tabular}{c c c c c} \hline \hline  & \multicolumn{3}{c}{**Natural Community**} & \multicolumn{3}{c}{**Synthetic Community**} \\ \cline{2-5}
**Compounds** & **With Packing** & **Without Packing** & **With Packing** & **Without Packing** \\ \hline Isoamyl acetate & \(1.78\pm 0.3\) & \(2.00\pm 0.46\) & Nd & Nd \\ Phenethyl acetate & \(1159.08\pm 69.74\) & \(7.92\pm 0.95\) & Nd & Nd \\ Ethyl propionate & \(4.85\pm 0.15\) & Nd & Nd & Nd \\ Ethyl myristate & \(3.29\pm 0.1\) & Nd & Nd & Nd \\ Ethyl seiterate & \(3.03\pm 0.8\) & Nd & Nd & Nd \\ Ethyl laurate & Nd & \(26.58\pm 16.80\) & Nd & Nd \\ Ethyl Acetate & \(3.16\pm 1.19\) & \(1.65\pm 0.12\) & Nd & Nd \\ Ethyl lactate & Nd & Nd & \(2.5\pm 0.2\) & Nd \\ Ethyl Oleate & \(9.12\pm 0.98\) & \(2.97\pm 1.61\) & Nd & Nd \\ Ethyl Isobutyrate & Nd & Nd & \(16.62\pm 0.89\) & Nd \\ Ethyl palmit & \(28.33\pm 17.45\) & \(3.64\pm 1.07\) & Nd & Nd \\ Isobutyl acetate & \(43.14\pm 6.43\) & \(34.01\pm 14.05\) & Nd & Nd \\ Isovaleric acid & Nd & \(23.69\pm 6.19\) & Nd & \(275.58\pm 45.67\) \\ Pentanoic acid & Nd & Nd & \(124.72\pm 13.45\) & \(593.58\pm 34.23\) \\ Acetic acid & \(23.31\pm 2.63\) & \(8.53\pm 6.03\) & \(4.13\pm 0.56\) & \(1017.38\pm 21.12\) \\
1-Hexanol & \(40.66\pm 6.89\) & Nd & Nd & \(18.82\pm 0.93\) \\ Isobutanol & \(3.24\pm 0.3\) & \(210.87\pm 140.32\) & Nd & Nd \\ Methinol & Nd & \(4.35\pm 2.75\) & Nd & Nd \\ Propanol & Nd & Nd & \(10.41\pm 2.34\) & Nd \\ Butanol & Nd & Nd & \(10.72\pm 3.23\) & Nd \\
1-Methyl-butanol & Nd & Nd & \(5.04\pm 0.12\) & Nd \\
2-methyl-butanol & Nd & Nd & \(158.59\pm 13.89\) & Nd \\ Isobutyl alcohol & Nd & Nd & \(378.19\pm 16.78\) & Nd \\ Isoamyl alcohol & \(2374.62\pm 64.32\) & \(1703.32\pm 19.8\) & \(4247.63\pm 234.89\) & \(256.69\pm 13.89\) \\ Guatacol & \(3.29\pm 0.5\) & Nd & Nd & \(3594.66\pm 84.91\) \\ Phenylethyl Alcohol & \(1902.86\pm 89.90\) & \(0.58\pm 0.41\) & \(2017.87\pm 89.78\) & Nd \\
2,3-Butanediol & \(47.80\pm 1.21\) & Nd & Nd & \(2070.68\pm 34.37\) \\ Benzaldehyde & \(25.50\pm 5.25\) & \(136.39\pm 17.50\) & \(91.75\pm 7.62\) & Nd \\ Acetaldehyde & \(2.78\pm 0.67\) & Nd & Nd & \(559.68\pm 23.34\) \\ \hline \hline \end{tabular}
\end{table}