出版社：Instituto Oceanográfico da Universidade de São Paulo
摘要：In the present study, several physiological responses of the red marine alga Porphyra haitanesis to elevated concentrations of copper (up to 50 μM) and zinc (up to 100 μM) were investigated.Our results showed that the effects of Cu2 and Zn2 on growth, photosynthetic pigments (chlorophylls and carotenoids), phycobiliprotein and metabolism (the fluorescence emission spectra and the activities of photosystemII) did not follow the same pattern.The relative growth rate was inhibited by different concentrations of Cu2 , and was slightly increased at lower concentrations (up to 10 μM) and inhibited at higher Zn2 concentrations.On the other hand, the phycoerythrin contents were slightly increased at relatively low concentrations (up to 1 μM Cu2 or 20 μM Zn2 ) and inhibited by high Cu2 and Zn2 concentrations.Moreover, photosynthesis and respiration showed an increase in the amount of oxygen exchange in response to relatively low Cu2 (up to 1 μM) and Zn2 concentrations (up to 10 μM), and a reduction to relatively high Cu2 and Zn2 concentrations.Oxygen evolution was more sensitive than oxygen uptake to Cu2 and Zn2 .In addition, the photoreductive activities and fluorescence emission of photosystem II (PS II) were enhanced by lower concentrations of Cu2 (up to 0.1 μM) and Zn2 (up to 10 μM) and inhibited by higher concentrations.Furthermore, the intensity of chlorophyll a fluorescence and the active PSII reaction centers followed a similar pattern in response to elevated concentrations of Cu2 and Zn2 .These results suggest that lower concentrations of Cu2 and Zn2 affected the metabolism of P.haitanesis, which was inhibited by higher concentrations of these metals.
关键词：Porphyra haitanesis;Cobre;Zinco;Fotossistema II
其他关键词：Porphyra haitanesis;Copper;Zinc;Photosystem II
