Geology Reference
In-Depth Information
Metasequoia glyptostroboides
a
After extraction
C 16S FA
m/z 83+85
C 16U FA
G
G
C 18 FA
P v
Ps
Ps Ps
G
G
P
Ps
P1
St
C 1 I
C 16U FA
C 18S FA
G
Ps
P s
Ps
Retention time
b
After base hydrolysis
m/z 83+85
G
G
G
P2
Ps
P1
Ps
G
G
Ps
P
St
Ps
Ps
Retention time
Fig. 2.5 Partial ion chromatogram showing the pyrolysis-GC/MS analysis of modern Metasequoia
glyptostroboides leaf ( a ) after lipid extraction (Residue 1); and ( b ) after lipid extraction followed
by saponifi cation (Residue 2). Note the presence of long-chain n -alkane/alk-1-ene homologues in
trace amounts in the extracted plant tissue and its absence post saponifi cation (as revealed by inset
m/z 83 + 85 mass chromatograms). Other legends same as in Figs. 2.2 and 2.3
Figure 2.5a shows the pyrolysis trace of the gymnosperm Metasequoia
glyptostroboides . Lignin, polysaccharides and cutin moieties are abundant, whereas
the n -alkanes and n -alk-1-enes are detected in extremely subordinate relative abun-
dance (also see inset m/z 83 + 85 mass chromatogram; Yang et al. 2005 , Fig. 3). The
pyrolysate of Residue 2 post saponifi cation (Fig. 2.5b ) similarly contains polysac-
charide and lignin moieties but no aliphatic component.
Data on all species investigated as part of this study are presented in Table 2.1 . In
all of these apart from Agave , Prunus and Clivia (see above), n -alkane/alk-1-ene
homologues were present in the pyrolysate of Residue 1, albeit in low (but variable)
 
Search WWH ::




Custom Search