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450 PROCEEDINGS OF INTERNATIONAL SCIENTIFIC CONFERENCE ON APPLIED BIOTECHNOLOGYof lignocellulosic materials using cellulase and xylanase of bacteria to obtain second-generation ethanol and other valueadded bioproducts. However, the pretreatment of lignocellulosic biomass is an important factor in increasing the efficiency of the hydrolysis process and reducing the cost, studies have also demonstrated the improvement in combining surfactants with enzymes, the results show that when surfactants are added, the concentration of enzymes used is also significantly reduced and the hydrolysis efficiency of cellulose is improved [25]. Zheng et al. evaluated the influence of Tween 20 and Tween 80, showing that when being combined with Tween 20, the concentration of enzymes was doubled reduced. Similarly, the study by SanchezMunoz and colleagues also showed that when combining Tween 20 and PEG400, the amount of enzymes used was reduced by 4 times compared to the control sample without surfactants [26, 27]. These studies demonstrate that the combination of surfactants and enzymes can increase the efficiency of the hydrolysis process, and these are also suggestive studies for future studies on the combination of additives with enzymes, which can significantly reduce the cost of enzymes in the hydrolysis of lignocellulosic biomass. However, the application of these surfactants also needs to be optimized to have a positive impact on the overall cost of the process. Tu and Saddler evaluated the cost reduction in the overall bioethanol production process by using surfactants at each step and showed that the addition of Tween 80 to the hydrolysis of pretreated softwood achieved a reduction in the cost of enzymes, material cost and process cost by 60%, 24% and 8.6%, respectively [28]. To overcome the economic performance, further studies are needed focusing on the application of non-ionic surfactants, as well as other additives to enhance the operating conditions for the implementation of these additives with economic feasibility.