Bioethanol production potential in Bangladesh from wild date palm (Phoenix sylvestris Roxb.): An experimental proof

[Display omitted] •Bioethanol production potentiality from wild date palm experimentally explored.•Female cultivar exhibited superior biomass yield than male cultivar.•Fruit pulp predominantly contain reducing sugar and sap having sucrose.•A hectare of fully grown plants could yield a minimum of 8076 L of ethanol. To sustain economic growth in Bangladesh, energy demand is expected to increase rapidly, resulting in more greenhouse gas emissions, as the energy sector, including transport and electricity, is dominated by fossil fuels. In order to reduce these emissions, the government of Bangladesh has already formed a long-term energy plan, part of which is introducing a 5% blend of bioethanol with gasoline in the transport sector. However, the source of this bioethanol has not yet been identified. An investigation has thus been conducted to evaluate the potential of bioethanol production using wild date palm fruit pulp and sap, sugary biomass of a perennially grown plant in Bangladesh that has been grown for decades without regular agronomic practice. A male plant produced 140.42 kg sugary biomass per year with 29.85% total sugar whereas a female plant yielded 195.56 kg, containing an average of 43.61% of total sugar. A batch fermentation study using Saccharomyces cerevisiae found that fruit pulp extract and sap could be conveniently fermented without nutritional supplementation to potentially yield ethanol. An average of 0.278 g/g ethanol was yielded from the fruit pulp extract and sap fermentation. From these findings, it was estimated that minimum 8076.62 L of ethanol could be obtained from an orchard comprising 500 plants per hectare with the planting ratio of male: female plants of 1:4. This indicates that this biomass of the wild date palm is a highly promising sugary feedstock for the potential production of bioethanol.