Understanding yeast tolerance as cell factory for bioethanol production from lignocellulosic biomass

Cell factory is the most important machinery for bioproduct. Yeast cell is known as the most productive machinery for ethanol production regarding its robustness toward high concentration of ethanol in the environment. However, it is become challenging when using lignocellulosic hydrolysate as raw material. For ethanol production, fermentation process depends on its cell's vitality under stress condition by ethanol accumulation in the environment. Furthermore, ethanol production using lignocellulosic hydrolysate undergo various challenges against inhibitory chemical complex such as 2-furaldehyde (furfural), 5-hydroxymethylfurfural (HMF), syringaldehyde, and vanillin coupled with some cell membrane-permeative acids, such as acetic acid, formic acid, and a small fraction of levulinic acid. Yeast cell maintains its survival on the stress condition by modification of its the genes regulation. Several considerations should be sought to engineered yeast as cell factory for ethanol production using lignocellulosic hydrolysate. This paper will discuss yeast survival mechanism toward its product and lignocellulosic hydrolysate environment, inhibitors effect to yeast cell, and gene regulation toward lignocellulosic hydrolysate for bioethanol production.