Ultrasonic treatment suppresses ethylene signaling and prolongs the freshness of spinach

Shoji Oda; Masaaki Sakaguchi; Xiesong Yang; Qinyao Liu; Kohei Iwasaki; Kaori Nishibayashi

doi:10.1016/j.fochms.2021.100026

Ultrasonic treatment suppresses ethylene signaling and prolongs the freshness of spinach

Food Chem (Oxf). 2021 May 11:2:100026. doi: 10.1016/j.fochms.2021.100026. eCollection 2021 Jul 30.

Authors

Shoji Oda¹, Masaaki Sakaguchi¹, Xiesong Yang¹, Qinyao Liu¹, Kohei Iwasaki², Kaori Nishibayashi²

Affiliations

¹ Department of Integrated Biosciences, Graduated School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba 2778562, Japan.
² Kashiwanoha Urban Planning and Development Department/Venture Co-creation Department, Mitsui Fudosan Co., Ltd., Kashiwa, Chiba 2778519, Japan.

Abstract

There have been many studies investigating the application of ultrasonic treatment in vegetables and fruits to eliminate surface contaminants including dirt, microbes, and chemicals such as pesticides. Using a jet ultrasonic washer developed by us to wash food materials, we found that ultrasonic treatment prolonged the freshness of spinach. The stomata closed in the ultrasonicated spinach leaves, whereas those in spinach soaked in water remained open during 24-h storage. Transcriptome analysis revealed that the expression of Ethylene-insensitive 3 Binding F-box protein 1 and 2 (EBF1 and EBF2), which inhibit ethylene signaling, was remarkably increased by ultrasonic treatment, suggesting that the suppression of ethylene signaling allowed stomatal closure in response to abscisic acid signals in the ultrasonicated leaves. Although the precise mechanism of the induction of EBF1 and EBF2 expression by ultrasonic treatment needs to be addressed in further studies, our findings suggest that ultrasonic treatment can be applied to revive and prolong the freshness of leaf vegetables, as well as for their cleaning.

Keywords: Abscisic acid; Ethylene; Ethylene-insensitive 3 binding F-box protein; Spinach; Stoma; Ultrasonication.