Maximum biodegradability of 80% was achieved from SSAD
of EFB at 16% TS and C:N ratio of 30:1, while only 7–15% was
achieved from EFB at 35% TS and of C:N ratio of 30:1 and 40:1. Previous
report shows a wide range of optimal C:N ratios (10–90) in
methane fermentation, however, a C:N ratio ranged of 29:1–30:1
is being the most common optimum C:N ratio in SS-AD (Yen and
Brune, 2007; Yan et al., 2015)