Abstract
Submicrosecond time-resolved absorption spectra were recorded for the core (RC-LH1) complexes from purple photosynthetic bacteria, which contain carotenoids(Cars) having different conjugation length (n), Rba. sphaeroides G1C, Rba. sphaeroides 2.4.1, Rsp. molischianum, Rps. acidophila 10050 and Rsp. rubrum S1 with and without sodium ascorbate under the argon atmosphere. In the absence of sodium ascorbate, all-trans type Tn ← T1 absorptions which are reflected in Car composition are ascribable to the LH1 components in core complexes. The lifetimes of the LH1 components give rise to linear relations as functions of 1/(2n + 1); Cars having a longer-conjugated chain tend to decay faster than those having shorter-conjugated chain. On the other hand, with sodium ascorbate, additional 15-cis type Tn ← T1 absorption was observed. It seems the RC component in core complexes. The lifetimes of RC components decay with the same rate among the set of Cars having different conjugation length.
