Hydrogen becomes a promising alternative energy carrier to fossil fuels since it is clean, renewable, contains high energy
content and does not contribute to greenhouse effect. Therefore, using cheap or renewable resources, such as lignocellulosic
materials, as the feedstock for hydrogen production, in particular, dark fermentative hydrogen production has a great potential
to give major contribution to future energy supply. The main challenges are the low hydrogen yield arising from poor efficiency
on direct microbial assimilation of cellulosic materials. Considerable research efforts have been made to improve the pretreatment
and hydrolysis of lignocellulosic materials. Development of novel and effective cellulase enzymes, optimization and improvement
of cellulase system, as well as engineering approaches on cellulose pretreatment and saccharification are gaining increasing
interest. Information from genomics and molecular genetics combined with improved genetic engineering offer a wide range of
possibilities for enhancing performance of cellulose feedstock utilization and biohydrogen production. This study reviews key
technologies and variables to be considered during biohydrogen production from lignocellulosic feedstock.