In 2006, the early study conveying the idea adopting palm oil mill effluent as supplementary substrate in the anaerobic contact filter system (under mesophilic conditions) has been advocated by Vijayaraghavan and Ahmad [34] (Fig. 1), signifying a cumulative biogas generation of 11.8 L/week (56% hydrogen) corresponding to chemical oxygen demand (COD) removal of 67%. Relatively, O-Thong et al. [32] and [33] have assessed tentative emphases for specific detection of the spatial distribution of hydrogen producing bacteria and optimization of the thermophilic fementative system, denoting a hydrogen production of 6.51 H2/L couple with a COD discrimination of 58% (Fig. 2). Upon the dark fermentative transformation, hydration of glucose molecule elucidates a concurrent generation of hydrogen and acetic acids in the ratio of 2:1 (Eq. (1)), which for favorable conversion of butyric acids, the portion of hydrogen produced is reduced proportionally (Eq. (2)).