Table I. Geometric isomers accumulating in y9 etiolated leaves and dark-grown E. coli.

Nd, Not detected. Numbers in y9 and EBP columns correspond to percentage of total ζ-carotene based on peak area relative to total peak area of six ζ-carotene peaks.

Carotene	y9		EBP		λmaxa	Percentage III/IIb
	Etiolated Leaves	12-h Light Treatment	Dark	12-h Light Treatment
					nm
Tri-cis-ζ-carotene	92.05 ± 1.51	2.62 ± 2.20	34.77 ± 1.53	0.31 ± 0.12	(296) 378 399 423	75
ζ-2	Nd	Nd	2.28 ± 0.90	0.74 ± 0.10	(296) 374 396 419	87
ζ-3	Nd	Nd	1.60 ± 0.56	0.67 ± 0.10	(296) 374 396 419	93
Di-cis-ζ-carotene	6.39 ± 0.77	88.06 ± 1.18	32.85 ± 1.05	53.27 ± 3.38	380 400 425	103
ζ-5	1.55 ± 0.76	1.28 ± 1.69	23.16 ± 0.61	31.86 ± 1.63	380 400 425	102
ζ-6	Nd	Nd	5.33 ± 0.50	9.51 ± 1.08	378 400 425	100

^aAbsorbance spectra taken during HPLC separation. The underlined peak is the highest peak (II); parentheses indicate an additional cis-peak.

^bFine structure of the absorption spectra expressed as the relative heights of the longest wavelength peak (III) to the middle peak (II).