**2. Oil palm biomass**

The biomass of the oil palm is a lignocellulosic biomass made up mainly of cellulose, hemicellulose, and lignin. The key component of oil palm biomass is cellulose

**Figure 1.** *Structure molecules; (a) cellulose; (b) hemicellulose, (c) lignin.*

#### *Lignocellulosic of Oil Palm Biomass to Chemical Product via Fermentation DOI: http://dx.doi.org/10.5772/intechopen.99312*

(C6H10O5)n (**Figure 1a**) which is the main component of oil palm biomass. Cellulose is a rigid, solid, and difficult-to-break linear polymer of glucose with additional hydrogen bonding [5]. By adding water to the polysaccharide, it is hydrolyzed into free sugar molecules (i.e. glucose, sucrose, and fructose) [6]. Saccharification is another name for this method.

Hemicellulose (C5 H8O4)n (**Figure 1b**), on the other hand, is made up of small, highly branched chains of various pentoses (such as xylose and arabinose) and hexoses and is found in secondary cell walls (i.e. mannose, galactose and glucose). Hemicellulose is simpler to hydrolyze than cellulose because of its weaker amorphous and branched structures [7].

The main non-carbohydrate component is lignin [C9H10O3(OCH3)0.9–1.7]n (**Figure 1c**), which is a highly complex compound with a three-dimensional crosslinked polyphenolic structure [4]. Lignin is found between the cellulose cell wall and the hemicellulose cell wall, and it is responsible for the cell wall and the plant's overall strength. As a result, when used as a lignocellulosic biomass in the fermentation process, lignin presents a significant disadvantage because it is resistant to chemical and biological degradation.
