不同糖处理对离体青花菜抗氧化酶以及品质的影响

Effects of Different Sugar Treatments on the Activity of In Vitro Antioxidant Enzymes and Quality of Broccoli

摘要:

本文采用含有150 mmol/L葡萄糖、果糖、蔗糖的培养基对青花菜花蕾进行离体培养，研究了外源糖对青花菜抗氧化酶活性以及品质的影响。结果表明，葡萄糖、果糖、蔗糖处理均能有效延缓离体青花菜黄化和抑制叶绿素的降解，而空白组青花菜完全黄化，果糖组处理组叶绿素含量最高，是空白组的1.83倍；外源糖处理能有效提高青花菜中过氧化氢酶（catalase, CAT）、过氧化物酶（peroxidase, POD）、过氧化物歧化酶（superoxide dismutase, SOD）及抗坏血酸过氧化物酶（ascorbate peroxidase, APX）的活性，但三种糖的效果并不相同，三种糖中，果糖能维持最高水平CAT和APX活性，蔗糖则保持最高的POD、SOD活性；三种外源糖处理不能提高离体青花菜总酚含量，但均能维持离体青花菜较高水平的总糖含量、总黄酮含量，提高DPPH自由基清除率，保持了青花菜较好的品质。

Abstract:

In vitro culturing of broccoli florets was carried out in a medium containing 150 mM glucose, fructose, or sucrose, to study the effects of various exogenous sugars on the antioxidant enzyme activities and the quality of broccoli. All three sugar treatments could effectively delay the de-greening of detached broccoli florets and inhibit the degradation of chlorophyll, whereas the florets of non-treated broccoli turned completely yellow. The highest chlorophyll content was found in the fructose treatment group and was 1.83 times higher than that of the non-treated control group. The activities of antioxidant enzymes, including catalase (CAT), peroxidase (POD), superoxide dismutase (SOD), and ascorbate peroxidase (APX), were effectively enhanced under these exogenous sugar treatments, albeit the effect of each sugar was different. The fructose-treated florets had the highest CAT and APX activities, whereas the sucrose-treated florets had the highest POD and SOD activities. The sugar treatments did not enhance the total phenolic content in the detached broccoli, but resulted in relatively high levels of total sugars and total flavonoids, as well as enhanced 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity, and maintained a relatively good quality of the broccoli.