The archaeal community of the SS-AD was clearly dominated by
members of the genus Methanoculleus sp. (Fig. 5B). The archaeal
community in SS-AD of oil palm biomass under optimum condition
(F:I 2:1, C:N 30:1 and 16% TS) of EFB and OPF was comprised of
Desulfurococcus sp., Methanospirillum sp., Methanosarcina sp. and
Methanomassiliicoccus sp. While, OPT was comprised of
Methanocaldococcus sp., Methanospirillum sp. Methanoculleus sp.
and Methanospirillum sp. Archaeal methanogen Methanoculleus
sp. play a dominant role in methane production from oil palm biomass
via SS-AD process. Methanosarcina sp. are able to use both the
acetoclastic and the hydrogenotrophic methanogens, making them
more tolerant to acetic acid (Vrieze et al., 2012