Chemistry Reference
In-Depth Information
0.10
447 nm
475 nm
0.08
0.06
0.04
0.02
0.00
300
400
500
600
(a)
Wavelength (nm)
Scan AP +
1.78e4
Cone voltage 5
551.4; 17799
100
Principle ion
M
+1-H
2
O
OH
%
HO
Parent ion
M
+1
569.4
1344
0
m/z
300
325
350
375
400
425
450
475
500
525
550
575
600
625
650
675
700
725
750
(b)
FIGURE 25.4
(a) UV/visible spectrum for the component eluting at 10 min is a characteristic of lutein with
l
max
at 447 nm; the ratio of the peak to the valley height of the 447 and the 475 nm absorptions matches the
expected value of 0.6. (b) The mass spectrum of the same component exhibits the parent
M
+ 1 ion (569
e
/
z
)
and the principle ion associated with the loss of water from the parent,
M
+ 1−H
2
O (551
e
/
z
).
(head (left) to tail (right)). The average lutein concentration in the front zone (site A, Figure 25.2b
and c) was measured to be 7.1 ±0.7 pmole/mm
2
and decreased to 4.0 ± 1.4 and 2.8 ± 1.0 pmole/mm
2
at sites B and C, respectively (Figure 25.7). The somewhat lower concentration of lutein observed
in these wider bands distinguishes them from that observed from the sampling of narrower yellow
bands, see Figures 25.2 and 25.6.
25.3.4.2 Queen, Eastern Black Swallowtail, and Atala Butterl ies
Queen butterl y larva (
Danaus gillipus
) belongs to the same genus as the Monarch and shares
a similar coloration pattern consisting of yellow, black, and white markings although the shapes
differ and there is also a reddish purple pigmentation in the darker pigmented regions, see
Figure 25.1c. The Eastern Black Swallowtail (
Papilio polyxenes asterius
) is characterized by green,
black, and yellow markings, Figure 25.1b. The small (
1 cm) Atala larvae (
Eurnaceus atala l orida
)
are uniquely red with seven pairs of intense yellow spots (
∼
1 mm), Figure 25.1d. Figure 25.8 shows
a comparison of the amount of lutein found in the various colored regions of these organisms to that
∼
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