Masashi HATAMOTO

Cultivation, Identification and Specific Detection of Anaerobic, Long-Chain Fatty Acids
Degrading Microbes from Methanogenic Sludge Treating a Wastewater Containing High Strength of Lipid.

Akiyoshi OHASHI, Hideki HARADA, Hiroyuki IMACHI

To address the fundamental information of microbes responsible for anaerobic degradation of long-chain
fatty acids (LCFA), enrichment and attempts at isolation of those microbes were performed. Primary
enrichment cultures were made with each of four LCFA substrates (palmitate, stearate, oleate and linoleate,

as a sole energy source) at 55��C or 37��C with two sources of anaerobic granular sludge as the inoculum.
After several successive transfers of these enrichments, 16S rRNA gene-based cloning and in situ hybridization
were done for the bacterial populations reside in the enrichments. As a result, anaerobic degradation of LCFA
is possibly involved in not only microbes belonging to the family Syntrophomonadaceae, which contains all anaerobic
syntrophic LCFA degrader isolated so far, but also phylogenetically different group of bacteria. Several attempts
were made to isolate these microbes, strain TOL was successfully isolated form the thermophilic oleate-degrading
enrichment culture and a highly purified culture which could degrade palmitate in syntrophic association of

hydrogenotrophic methanogens from thermophilic palmitate-degrading enrichment culture.