Effects of CaCl2 Treatment Alleviates Chilling Injury of Loquat Fruit (Eribotrya japonica) by Modulating ROS Homeostasis.

Yuanyuan Hou,Peng Jin,Ziying Li,Yonghua Zheng

doi:10.3390/foods10071662

Abstract

The effects of calcium chloride (CaCl2) treatment on chilling injury (CI), reactive oxygen species (ROS) metabolism, and ascorbate-glutathione (AsA-GSH) cycle in loquat fruit at 1 °C storage for 35 d were investigated. The results indicated that CaCl2 treatment remarkably suppressed the increase in browning index and firmness as well as the decrease in extractable juice rate. CaCl2 treatment also decreased the production of superoxide radical (), hydrogen peroxide (H2O2) content, but increased the 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl radical () scavenging ability, the activities of superoxide dismutase (SOD), catalase (CAT), and their gene expressions. Moreover, compared to the control loquat fruit, CaCl2-treated fruit maintained higher contents of AsA, GSH, higher levels of activities of ascorbate peroxidase (APX), glutathione reductase (GR), dehydroascorbate reductase (DHAR), and monodehydroascorbate reductase (MDHAR) and expressions of EjAPX, EjGR, EjMDHAR, and EjDHAR, but exhibited lower glutathione disulfide (GSSG) content. These results suggested that CaCl2 treatment alleviated CI in loquat fruit through enhancing antioxidant enzymes activities and AsA-GSH cycle system to quench ROS.

Highlights

Loquat (Eriobotrya japonica Lindl.), as a type of non-climacteric fruit, presents a short postharvest life at ambient temperature because of its physiological deterioration and microbial decay
It is well-established that the occurrence of chilling injury in higher plants is closely associated with oxidative stress resulted from excessive reactive oxygen species (ROS) such as superoxide anion (O2− ), hydrogen peroxide (H2 O2 ), and hydroxyl radical (OH ) [3]
CaCl2 Treatment on Internal Browning Index, Fruit Firmness, Extractable Juice of Loquat FruitInternal browning in loquat fruit occurred on the 21st day of storage and increased fruit occurred on thesignificantly

Summary

Introduction

Loquat (Eriobotrya japonica Lindl.), as a type of non-climacteric fruit, presents a short postharvest life at ambient temperature because of its physiological deterioration and microbial decay. The exploration into the mechanism of CI in loquat fruit is of great significance It is well-established that the occurrence of chilling injury in higher plants is closely associated with oxidative stress resulted from excessive reactive oxygen species (ROS) such as superoxide anion (O2− ), hydrogen peroxide (H2 O2 ), and hydroxyl radical (OH ) [3]. This large quantity of ROS accumulation alter the membrane organization and cause or exacerbate lipid peroxidation, leading to damage to the cell system [4]. Superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) are primary antioxidant enzymes, while ascorbate (AsA) and glutathione (GSH) are non-enzymatic antioxidants [5]

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Results

Discussion

Conclusion