1. Main Types of Hemicelluloses Found in Diverse Feedstocks (Adapted from Girio et al. 2010) .

				units
type of hemicellulose sugar	feedstock type	content	degree of polymerization	backbone	side chain
arabinogalactan (AG)	softwoods	up to 35 wt%	100–600	β-d-Galp	β-d-Galp
					α-l-Araf
					β-l-Arap
xyloglucan (XG)	hardwoods, grasses	2–25 wt%		β-d-Glcp	β-d-Xylp
				β-d-Xylo	β-d-Galp
					α-l-Araf
					α-l-Fucp
					acetyl
galactoglucomannan (GGM)	softwoods	10–25 wt%	40–100	β-d-Manp	β-d-Galp
				β-d-Glcp	acetyl
glucomannan (GM)	softwoods and hardwoods	2–5 wt%	40–70	β-d-Manp
				β-d-Glcp
glucuronoxylan (GX)	hardwoods	15–30 wt%	100–200	β-d-Xylp	4-O-Me-α-d-GlcpA
					acetyl
arabinoglucuronoxylan (AGX)	grasses, cereals and softwoods	5–10 wt%	50–185	β-d-Xylp	4-O-Me-α-d-GlcpAβ-l-Araf
arabinoxylans (AX)	cereals	0.15–30.0 wt%		α-l-Araf Feruloy	α-l-Araf
					4-O-Me-α-d-GlcpA
					acetyl
glucuronoarabinoxylans (GAX)	grasses and cereals	15–30 wt%		α-l-Araf
				4-O-Me-α-d-GlcpA
				acetyl
homoxylans (X)	algae			β-d-Xylp