利用RNO脱色反应检测类囊体中的单线态氧

光敏剂RB在光照射下与O₂反应产生 ¹O₂， ¹O₂与组氨酸或咪唑反应的中间产物使RNO发生氧化，导致RNO在440 nm处吸光度减小，此即为RNO脱色反应.RNO脱色反应随着光照时间的增加而增大，表明RB受光照射后使 ¹O₂增加；随着组氨酸或咪唑浓度的增加，RNO脱色反应增大；咪唑在RNO脱色反应中的作用更明显. ¹O₂淬灭剂NaN₃或DABCO存在时，RNO脱色反应降低.利用RNO脱色反应检测到莴苣类囊体在强光照射下产生的 ¹O₂，随着光强和照射时间增加，类囊体中 ¹O₂的产生增加.

Detection of Singlet Oxygen by the Bleaching of RNO in Thylakoids

Photosensitizer rose bengal (RB) reacts with O₂ to generate singlet oxygen ( ¹O₂) under illumination. ¹O₂ reacts with histidine or imidazole to form intermediate products which oxidize RNO. The reaction causes optical absorption of RNO at 440 nm to decrease. It is named the bleaching of RNO. Bleaching of RNO is increased with the increasing of RB illuminated time, which shows that the production of ¹O₂ has grown in the reaction. Bleaching of RNO is promoted by the rising of the concentration of histidine or imidazole. Imidazole plays more evident role in the reaction than histidine does. Bleaching of RNO is decreased by the presence of ¹O₂ quencher NaN₃ or DABCO. ¹O₂ in lettuce thylakoids has been detected by the reaction in strong light. The production of ¹O₂ grows with the increasing of light intensity and illuminated time in lettuce thylakoids.