Abstract:

In this study, effects of metal ion, NaOH, light and H2O2 on stability of carotenoids from photosynthetic bacteria were investigated. It was found that K+, Na+, Mg2+, Al3+, Ca2+ and NaOH with low concentration (less than 0.01 mol/L) have little effects on the stability of carotenoids, while Fe3+ , Cu2+ and NaOH with high concentration(more than 0.5 mol/L)may lead to great loss of carotenoids. The carotenoids are sensitive to light and the damage effects of lights from different sources on stability of carotenoids decrease as following: natural light ＞ bulb light ＞ fluorescent light ＞ ultraviolet light. But the carotenoids are stable to H2O2, only a little carotenoids are decomposed when H2O2 exists.

Key words: photosynthetic bacteria, carotenoids, stability