초록
<P><B>Abstract</B></P><P><B>Aims</B></P><P>Microbial consortia can be more efficient at biological processes than single isolates. The purposes of this study were to design and evaluate a synthetic microbial consortium containing the methanotroph <I>Methylocystis</I> sp. M6 and the helper <I>Hyphomicrobium</I> sp. NM3, and develop a novel methanotrophic process for this consortium utilizing a dialysis membrane.</P><P><B>Methods and Results</B></P><P><I>Hyphomicrobium</I> increased the methane‐oxidation rate (MOR), biomass and stability at a dilution rate of 0·067 day<SUP>−1</SUP> in fed‐batch co‐culture. qRT‐PCR showed that <I>Methylocystis</I> population increased gradually with time, whereas <I>Hyphomicrobium</I> population remained stable despite cell washing, confirming synergistic population interaction. At 0·1 day<SUP>−1</SUP>, spiking of <I>Hyphomicrobium</I> effectively increased the methanotrophic activity, after which <I>Hyphomicrobium</I> population decreased with time, indicating that the consortium is optimal at <0·1 day<SUP>−1</SUP>. When <I>Hyphomicrobium</I> was grown in dialysis membrane within the bioreactor, MOR increased linearly up to 155·1 ± 1·0 mmol l<SUP>−1</SUP> day<SUP>−1</SUP> at 0·067, 0·1, 0·2 and 0·4 day<SUP>−1</SUP>, which is the highest observed value for a methanotrophic reactor.</P><P><B>Conclusions</B></P><P><I>Hyphomicrobium</I> sp. NM3 is a promising helper micro‐organism for methanotrophs. <I>Hyphomicrobium</I>‐methanotroph consortia used concurrently with existing methods can produce an efficient and stable methane oxidation system.</P><P><B>Significance and Impact of the Study</B></P><P>This novel methanotrophic process is superior to those previously reported in the literature, and can provide efficient and stable methane oxidation.</P>