Integration of biogas derived from dark fermentation and anaerobic digestion of biowaste to enhance methanol production by methanotrophs

•Klebsiella aerogenes yielded 2.82 mol of H2/mol of hexose under dark fermentation.•Biogas derived from DF and anaerobic digestion is integrated to produce methanol.•Methanol production by methanotrophs was improved with methane vectors in the feed.•Under the repeated batch mode, 64.6 mmol/L of methanol was produced.