<![CDATA[Biohydrogen is one of the most desired clean source energy due to the multi-purpose function and its production can be achieved via dark and photofermentation. However, the challenge comes from the expense of utilized fermentation substrate. Hence, utilizing low-cost and abundance material is needed. Dairy wastewater is considered to be a desirable alternative substrate due to high organic content. Co-culture fermentation of Clostridium butyricum and Rhodopseudomonas palustris with sucrose-containing substrate increased hydrogen production yield better than using separated batches of both cultures. Volatile fatty acids (VFA) as the end-product of dark fermentation by Clostridium butyricum could be utilized by R. palustris. This literature research is addressing the potential of dairy wastewater as a co-culture fermentation substrate to increase biohydrogen yield in low-cost. The research method is a literature review using secondary data carried out by identifying, assessing, and interpreting findings on relevant research topics. The result of this research is dairy wastewater used as a co-culture fermentation substrate can enhance biohydrogen production by promoting growth rate of both bacteria and by increasing the production of VFA. The theoretical yield of biohydrogen produced from co-culture fermentation of dairy wastewater is 8,44 gram higher than the theoretical yield of biohydrogen produced from singular fermentation of non-wastewater substrate. Keywords: biohydrogen, co-culture fermentation, dairy wastewater]]>
