The batch fermentative hydrogen production using starch was conducted to investigate the influence of temperature (25 degrees C-40 degrees C) on the co-cultures system of Bacillus cereus ATCC 14579 (T) [Strain A] and Brevundimonas naejangsanensis BIO-TAS2-2(T) [Strain 13]. The results showed that the optimal temperature for hydrogen production was 35 degrees C in both the sole and the mixed culture fermentation. At this temperature, the co-culturing system increased the substrate consumption rate by 34 % and 70 % compared with the Strain A and Strain B fermentation, respectively. The co-culturing system enhanced the hydrogen production yield by 52 % and 62 % compared with the Strain A and Strain B fermentation, respectively. The analysis of soluble metabolites during the fermentation process indicated that the mixed acid fermentation conducted in two strains and co-culturing system was dominated by butyric acid type fermentation at the optimal temperature. The Formate pathway probably exists in Strain A, and the PFOR pathway probably exists in Strain B. Both strains A and B play a synergistic role in hydrogen production at 35 degrees C using starch as substrate, (C) 2019 Elsevier Ltd. All rights reserved.