*2.1. Worldwide Scenario of Biofuel Production*

We are strongly dependent on fossil fuels due to the extensive use and utilization of petroleum derivatives limiting the use of petroleum resources, resulting in environmental and political issues [17]. Questions regarding ecological stagnation and unpredictability dependent on the future reservoir and increasing oil prices have been inspiring methods relying on alternative energy sources [18]. At a national, regional, and global level, there is acceptance of plants' raw material (i.e., biomass) at an increased level. It can reinstate a large portion of fossil resources as feedstock for the industrial generation of both the energy and non-energy (i.e., chemicals and materials) area [17]. It has been reported to be approximately 2.7% of global transportation (~2.9 TW) that is dominated by first-generation biofuels. Ethanol derived from sugarcane and cornstarch (28 billion gallons in 2018) and biodiesel from rapeseed or soybean oils (8 billion gallons in 2018). These raw materials are also a segment of the food chain supply and do not serve a long-term, high-scale solution; therefore, first-generation biofuels will not be a considerable section of the transportation fuel supply in 2050. Therefore, it is essential to replace the 1G biofuels gradually with lignocellulosic biofuels [18].
