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SECTION II. APPLIED BIOTECHNOLOGY IN THE PHARMACEUTICAL INDUSTRY... 449between biomass, enzymes, and free water in the hydrolysis system. Therefore, it reduces the diffusion capacity of enzymes, substrates, and the conditions necessary for adsorption or desorption on the surface of lignocellulosic biomass [22]. In addition, the end products of hydrolysis such as cellobiose, xylan, xylooligosaccharides, glucose, other sugars and several inhibitors are produced during acid or base treatment such as: phenol, furfural, hydroxymethylfurfural, gluconic acid and others. High biomass concentration, reduced water in the hydrolyzed solution, low water activity, inhibitors can strongly bind to the catalytic sites of cellulose and hemicellulosic enzymes. The ineffective adsorption of enzymes on the surface of lignin complexes will also create a large barrier due to the strong binding at the catalytic and binding sites of enzymes [23].Surfactants are also used as additives in the pretreatment of lignocellulosic biomass for various purposes due to their ability to enhance the contact between reactants and biomass, reduce the interfacial tension between liquids, and improve the separation of lignin from biomass. Regarding surfactants in saccharification, there are several studies showing that surfactants are able to change the hydrophobicity of lignocellulosic biomass surface by loosening the crystal structure of cellulose and opening pores through the interlace structure of lignin on the outside of cellulose fibers, facilitating the adsorption or desorption of substrates and final products under the catalysis of enzymes. On the other hand, surfactants can also increase the availability of free water by reducing the air-solid-water interfacial tension and reducing the separation efficiency in the case of high solid concentration [24].4.4. Reducing the cost of using enzymes in enzymatic hydrolysisIn the second-generation bioethanol production technology, recently, researchers have been interested in enzymatic hydrolysis