Fossil fuels are fuels formed by natural processes
for example anaerobic decomposition of buried dead organisms. It
preserves a high percentage of coal, natural gas and carbon includes petroleum.
The extensively use of fossil fuels raises serious environmental issues. A 21.3 billion tonnes of carbon
dioxide was produce due to the burning of fossil fuels. Researchers trust that
critical environmental change will be unavoidability without an intense
decrease in the discharges of greenhouse gasses starting with the burning of
fossil fills. Thus, alternating energy source is needed to replace fossil fuels
to preserve a healthy environment.
the most abundant component in the universe. It has emerged as a promising alternative fuel that can
be produced from renewable resources including organic waste through biological
processes by algae, bacteria and archea. Biological productions of
biohydrogen technologies provide a wide range of approaches to generate
hydrogen, including direct biophotolysis, indirect biophotolysis,
photo-fermentations, and dark-fermentation (Levin, Pitt,
& Love, 2004).
In addition, burning hydrogen does not contribute to the greenhouse effect,
ozone depletion and acid rain. Thus, the use of hydrogen as an energy carrier
is a long-term option to reduce CO2 emissions and toxic gases.
. The generation of biohydrogen
via dark fermentation process is achieved mainly by strictly anaerobic or
facultative anaerobic bacteria under anaerobic conditions. This process is more
preferable than direct and indirect biophotolysis, and photofermentation. This is because, it can produce
hydrogen all day without light, no limitation oxygen, have simplest technology
and can degrade substrate with variety carbon source (Nath &
Although variety of organic substance can be used as substrate, it will
produce different amount of hydrogen depend on the substrate (Ntaikou,
Antonopoulou, & Lyberatos, 2010).
Cassava starch has several
industrial applications which create a huge global business. However,
the cassava starch industrial process generates very pollutant effluents that
need to be treated before discharge (Sánchez, Silva,
Kalid, Cohim, & Torres, 2017). The wastewater contains high level of
carbohydrate and organic content that are suitable for production of
biohydrogen. The production of hydrogen not only to stop the pollution but it
can be a solution to the depleted of fossil fuels. There are many facultative
microorganisms that are able to degrade starch from wastewater. Thus, the study
of biohydrogen production from starch wastewater should be done widely.
Microbes for fermentative
hydrogen production either belong to strict anaerobes or facultative anaerobes.
According to Bakonyi et al. (2012), Facultative anaerobe is considered a better
microorganism than a strict anaerobe to carry out hydrogen production processes
The reason is facultative anaerobes are less sensitive to oxygen and
sometimes able to recover hydrogen production activity after accidental oxygen
damage to them by rapidly depleting oxygen present in the broth. The ability of
these microorganism to produce biohydrogen depend the factors such as
temperature, pH and initial substrate concentration (Wang & Wan,