TABLE 2.

Identities and relative molar abundances of the compounds released after Py-GC/MS of whole cell walls (CW) of rice (Oryza sativa L.) husks and straw and their respective isolated MWLs.

			Rice husks		Rice straw
Label	Compound	Origin	CW	MWL	CW	MWL
1	Phenol	H	1.4	2.1	2.3	2.7
2	Guaiacol	G	6.4	8.8	5.1	8.0
3	3-methylphenol	H	0.8	0.6	0.9	0.6
4	4-methylphenol	H	1.8	3.1	3.5	3.4
5	4-methylguaiacol	G	8.3	13.1	5.9	8.3
6	4-ethylphenol	H	1.4	0.5	2.0	0.7
7	4-ethylguaiacol	G	2.5	2.9	4.6	3.8
8	4-vinylguaiacol	G/FA	12.4	15.4	19.6	14.5
9	4-vinylphenol	H/pCA	33.4	27.1	31.2	30.6
10	Eugenol	G	3.3	2.3	0.7	2.5
11	4-allylphenol	H	0.3	0.3	0.3	0.4
12	Syringol	S	1.0	1.8	2.1	3.5
13	cis-isoeugenol	G	2.2	1.1	0.6	1.0
14	cis-4-propenylphenol	H	0.2	0.2	0.2	0.2
15	trans-4-propenylphenol	H	0.6	0.6	1.1	0.5
16	trans-isoeugenol	G	4.3	4.7	2.6	2.6
17	4-methylsyringol	S	2.4	1.9	1.7	2.6
18	Vanillin	G	5.8	4.6	5.8	3.6
19	4-ethylsyringol	S	1.0	0.6	0.5	0.7
20	Vanillic acid methyl ester	G	0.3	0.4	0.2	0.4
21	Acetoguaiacone	G	0.9	0.9	0.8	0.7
22	4-vinylsyringol	S	0.9	1.2	0.3	2.2
23	Guaiacylacetone	G	2.8	1.3	2.2	1.1
24	4-allylsyringol	S	0.2	0.2	0.4	0.3
25	Propiovanillone	G	0.8	0.4	0.2	0.1
26	cis-4-propenylsyringol	S	0.2	0.2	0.5	0.3
27	trans-4-propenylsyringol	S	1.1	0.8	1.6	0.9
28	Vanillic acid	G	0.4	0.6	0.0	0.2
29	Syringaldehyde	S	0.6	0.7	0.6	0.8
30	Acetosyringone	S	0.5	1.3	1.4	2.5
31	Syringylacetone	S	0.3	0.3	1.0	0.3
32	trans-coniferaldehyde	G	1.5	0.0	0.0	0.0
33	Propiosyringone	S	0.1	0.1	0.3	0.2
	%H*=		12.2	13.0	21.0	16.2
	%G*=		74.2	73.0	58.4	61.0
	%S*=		13.6	14.0	20.6	22.8
	S/G ratio*=		0.18	0.19	0.35	0.37

*Calculated without taken into account the vinyl compounds 8, 9, and 22.H, p-hydroxyphenyl lignin units; G, guaiacyl lignin units; S, syringyl lignin units; pCA, p-coumarates; FA, ferulates.