Table 2.

Composition of the Ident-Mix (excerpt from Table S7). Shown are three different metabolite classes with potential identification problems based on compound and RI similarity. Most metabolites generate two peaks due to multiple derivatisation products, often with the second peak lower abundant. However, for fructose both peaks have nearly the same intensity (Figure 4a,b), so we list the RI for both peaks here. Colors are given to illustrate appropriately the same colour scheme as used in Figure 4.

Class	Compound	Expected RI	Ident Mix Occurrence
Pentoses	Xylose	1651	A		C
	Ribose	1672		B		D
	Arabitol	1711			C	D
	Ribitol	1716	A	B
Hexoses	Fructose	1862 and 1872		B	C
	Mannose	1876	A			D
	Galactose	1880	A		C
	Glucose	1886		B		D
Sugar Derivatives	Sorbitol	1926	A			D
	Glucuronic acid	1927	A		C
	Glucosamine	1932	A	B
	Galacturonic acid	1935		B		D
	Gluconic acid	1996		B	C