jacoline N-oxide, and jacozine) were significantly positively correlated. The other
jacobine-like PAs, most notably jaconine and jaconine N-oxide, and the other
otosenine-like PAs (desacetyldoronine and doronine) were absent on the leaf surface,
Table 1 Average relative concentration of the leaf-surface and leaf-tissue pyrrolizidine alkaloid
(PAs) from 37 F 2 hybrid individuals of a cross between Jacobaea aquatica and Jacobaea vulgaris
Group
Pyrrolizidine
alkaloid
Leaf-surface PAs
Leaf-tissue PAs
Relative
concentration
a
TA
%
b
Relative
concentration
TA
%
Senecioninelike PAs
Senecionine
15
2
4
1
Integerrimine
3
3
3
0.43
Retrorsine
0.46
31
0.57
2
Usaramine
n.d.
n.d.
0.85
1
Eruciflorine N-oxide
0.11
n.d.
0.01
0.00
Seneciphylline
29
1
19
1
Spartioidine
1
0.00 0.09
0.00
Riddelliine
1
33
1
0.00
Acetylseneciphylline 2
4
3
0.00
Jacobine-like
PAs
Jacobine
31
31
29
29
Jacoline
2
33
3
38
Jaconine
0.03
n.d.
0.00
0.00
Jacozine
3
54
6
47
Dehydrojacoline
n.d.
n.d.
0.44
100
Dehydrojaconine
n.d.
n.d.
0.26
81
Erucifolinelike PAs
Erucifoline
10
4
18
8
Acetylerucifoline
1
n.d.
0.15
35
Otosenine-like
PAs
Otosenine
1
100
1
100
Onetine
0.17
100
0.12
100
Desacetyldoronine
n.d.
n.d.
0.10
100
Florosenine
1
100
0.21
100
Floridanine
0.09
100
0.04
100
Doronine
n.d.
n.d.
0.09
100
Total PA free bases
23
20
Total PA N-oxides
77
80
Senecionine-like
PAs
51
2
32
1
Jacobine-like PAs
36
33
40
35
Erucifoline-like PAs
11
4
26
6
Otosenine-like PAs
2
100
2
100
Total PA
349 (pg cm
À2
)
3142 (μg g
À1
)
Adapted from Cheng et al. [44]
n.d. not detected
a Relative concentration = concentration of an individual or a group of PAs/total PA concentration Â
100
b
TA% = the tertiary amine concentration/(tertiary amine concentration + the corresponding N-oxide
concentration) Â 100
11 Variation in Leaf-Surface and Leaf-Tissue Secondary Metabolites:. . .
257