烘烤条件下烟叶抗坏血酸-谷胱甘肽循环系统的变化

The Changes of Ascorbic Acid-Glutathione Recycle System in Tobacco Leaves under Different Curing Conditions

采用河南农业大学设计的电热式温湿度自控烤烟箱,研究了不同烘烤条件对烤烟抗坏血酸-谷胱甘肽循环系统的影响.结果表明,抗坏血酸过氧化物酶(APX)和谷胱甘肽还原酶(GR)活性在烘烤前24～48h迅速升高,之后由于烟叶组织细胞受到持续的高温胁迫,APX和GR活性迅速降低,最终造成抗坏血酸-谷胱甘肽循环系统抗氧化能力丧失;烟叶在相对较低温度下适当延长变黄时间(T3),其APX和GR活性高峰出现较晚且其峰期持续时间长,与此相对应抗坏血酸(ASA)和谷胱甘肽(GSH)含量迅速上升阶段的时间也有所延长,使烟叶可在较长时间维持细胞活性,内含物质转化较为充分,烤后烟叶化学成分协调,可用性好.

The changes of ascorbic acid （ASA）-glutathione（GSH） recycle system in tobacco leaves under different curing conditions were studied by using the electric-heated auto-controlled flue-curing barn supplied by Henan Agricultural University, China. The results indicated that the activity of ascorbic acid peroxidase （APX） and glutathione reductase （GR） increased intensely before 24-48h in the flue-curing, then decreased rapidly because the tobacco leaves were intimidated by the steady high temperature, which caused the antioxidation abality of ASA-GSH recycle system deprivation; The activity peak of APX and GR emerged later and lasted longer when the tobacco leaves were treated by low temperature and long yellowing time （T3）, so the time that the content of ASA and GSH ascending was also longer, which resulted in the tissue of tobacco leaves could keep function in a long period of time, the embedded substance transformed sufficiency, the chemical composition were harmonized and the tobacco leaves had better usability.