复配精油纳米乳雾化处理对马铃薯发芽的抑制作用及机理探讨

Antigermination effect of compound essential oil nanoemulsion fogging on potato tuber and the exploration of the mechanism

该文采用水蒸馏法提取4种伞形科植物芫荽、莳萝、葛缕子和孜然的种子精油,将上述精油进行复配和纳米乳化处理,并用所得的复配精油纳米乳雾化处理马铃薯,研究其对马铃薯发芽的抑制效果,以及对马铃薯块茎活性氧和关键抗氧化物质含量及抗氧化酶活性影响。结果表明,复配精油纳米乳雾化能够明显抑制马铃薯块茎发芽,降低块茎过氧化氢含量,显著提高块茎的烟酰胺腺嘌呤二核苷酸磷酸(nicotinamide adenine dinucleotide phosphate,NADPH)和还原型谷胱甘肽含量,降低马铃薯块茎中总黄酮及总酚的含量;复配精油纳米乳雾化显著提高块茎部分关键抗氧化酶[过氧化氢酶(catalase,CAT);超氧化物岐化酶(superoxide dismutase,SOD);过氧化物酶(peroxidase,POD);多酚氧化酶(polyphenol oxidase,PPO)]的活性。由此可知,复配精油纳米乳通过调节马铃薯块茎关键抗氧化酶的活性和抗氧化物质含量来降低活性氧含量,从而延长马铃薯块茎的休眠期,达到抑制其发芽的效果。

The essential oils of four umbellifers(Cuminum cyminum L.,Coriandrum sativum L.,Carum carvi,Anethum graveolens L.)were hydro-distilled and the nanoemulsion of the compound essential oil was prepared.Potato tubers were fogged with the nanoemulsion to test its antigermination effect on potato tubers.To explore the antigermination mechanism,the contents of reactive oxygen species and key antioxidants,and the activities of key antioxidant enzymes of treated tubers were tested.The results showed that the fogging with the nanoemulsion significantly inhibited the germination of potato tubers and also reduced the content of tuber hydrogen peroxide.Besides,it could significantly increase the contents of nicotinamide adenine dinucleotide phosphate(NADPH).Moreover,glutathione and the contents of total flavonoids and total phenols of the tubers were also decreased.Furthermore,the activities of the key antioxidative enzymes in the tuber were significantly elevated by fogging treatment.In conclusion,nanoemulsion of the compound essential oil reduced the content of reactive oxygen species by adjusting the activities of key antioxidant enzymes and antioxidant contents of potato tuber,and thus extended the dormant period of potato tuber and inhibited its germination.