Effect of Irradiation and Immobilization on Spinach Chloroplast Activities
نویسندگان
چکیده
Radiation Effect, Chloroplast, 0 2 Evolution, Immobilization, Radiation Polymerization, Low Temperatures The effect of y-ray irradiation and immobilization by means of radiation polymerization on PS II activity ( 0 2 evolution) of isolated chloroplasts from spinach was investigated. Reduction of 0 2 evolution activity by irradiation was small at lower temperatures below — 24 °C, but the activity decreased slightly by freezing at extremely low temperature below —78 °C. So the optimum low temperature range for the treatment was observed. The immobilized chloroplast in a hydrophilic polymer matrix showed the stable duration of 0 2 evolution activity more than 700 h at 4°C . Thermo-stability of chloroplast was also improved greatly by immobilization. The active center of PS II in immobilized chloroplasts was retained even after 60 min standing at 50 °C.
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