用于测定抗氰呼吸途径活性的氧同位素分馏法和氧肟酸抑制法的比较

氧同位素分馏法和氧肟酸抑制法的测定结果都表明，马铃薯切片在１２ ～２４ ｈ 陈化期间抗氰呼吸途径的实际活性基本保持恒定，尽管前者的测定结果是后者的２ 倍。此外，用上述２ 种不同方法进行研究的结果都表明，内源乙烯在诱导陈化切片抗氰呼吸途径容量产生的同时并不调控其实际运行。上述结果表明尽管氧肟酸抑制法不能准确测定抗氰呼吸途径的实际活性，但用于一些比较研究仍是可行的

Comparison of the Estimation of the Operation of the Alternative Respiration Pathway Between with Oxygen isotope fractionation Method and with Hydroxamate inhibition Method

Using the conventional hydroxamate inhibition method the contributions of the in vivo alternative respiration pathway (ARP) activity to total respiration activity (V t) in aging potato ( Solanum tuberosum L.) tuber slices were determined to be at a stable level of about 16% from 12 to 24 h. With the oxygen isotope fractionation (OIF) method the ARP activities were about twice as high. However, ARP activities from 12 to 24 h evaluated by the OIF method also showed their stability during the aging process(Table 1). In addition, although the ARP activities measured by the OIF method were also twice as high as those by the hydroxamate inhibition method in slices treated with ACC and Co 2 , the results evaluated by none of the two methods showed any influence of endogenous ethylene on the in vivo ARP activities of the aging slices. Therefore, though the results confirm the conclusion that the hydroxamate inhibition method underestimates in vivo ARP activities in plants, it is still useful in comparative studies, because it can give nearly the same ratios between different states of the tissues and between different treatments and control as those given by the OIF method when the expensive equipment needed by the latter method is considered.