Heat Shock Treatment Promoted Callus Formation on Postharvest Sweet Potato by Adjusting Active Oxygen and Phenylpropanoid Metabolism

Abstract

This study aimed to investigate that rapid high-temperature treatment (RHT) at an appropriate temperature could accelerate callus formation by effectively promoting the necessary metabolic pathways in sweet potato callus. In this study, the callus of sweet potato was treated with heat shock at 50, 65, and 80 °C for 15 min. The callus formation was observed within 1, 3, and 5 days, and the accumulation of intermediates in the metabolism of phenylpropane and reactive oxygen species and changes in enzyme activities were determined. The results showed that appropriate RHT treatment at 65 °C stimulated the metabolism of reactive oxygen species at the injury site of sweet potato on the first day, and maintained a high level of reactive oxygen species production and scavenging within 5 days. The higher level of reactive oxygen species stimulated the phenylalanine ammonia-lyase (PAL), 4-coumarate-CoA ligase and cinnamate-4-hydroxylase activities of the phenylpropane metabolic pathway, and promoted the rapid synthesis of chlorogenic acid, p-coumaric acid, rutin, and caffeic acid at the injury site, which stacked to form callus. By Pearson’s correlation analysis, catalase (CAT), PAL, and chlorogenic acid content were found to be strongly positively correlated with changes in all metabolites and enzymatic activities. Our results indicated that appropriate high-temperature rapid treatment could promote sweet potato callus by inducing reactive oxygen species and phenylpropane metabolism; moreover, CAT, PAL, and chlorogenic acid were key factors in promoting two metabolic pathways in sweet potato callus.

Effects of Reactive Oxygen Levels on Chilling Injury and Storability in 21 Apricot Varieties from Different Production Areas in China

“…Hydrogen peroxide (H 2 O 2 ) content was tested according to [ 24 , 25 ] with some modifications. Apricot flesh tissue (10 g) was homogenized in 5 mL of cold acetone and centrifuged at 10,000× g and 4 °C for 30 min.…”

“…The determination of 1,1-dipheny1-2-Picryl-Hydrazyl (DPPH) clearance capacity referred to Xin et al [ 25 ] and was modified; 5 g of frozen callus were taken and placed in a centrifuge tube (50 mL). The 20 mL ethanol (70%) solution was added, mixed, and ultrasonically treated for 1 h, centrifuged (4 °C 10,000× g 20 min), and the supernatant was taken as the extract.…”

Abiotic Stresses, Biostimulants and Plant Activity

“…Since heat stress can influence the metabolic processes that enable callus formation, a study investigated the effect of rapid high-temperature (RHT) treatment at 50, 65, and 80 • C on sweet potato tubers [6]. The results showed that appropriate RHT treatment at 65 • C can stimulate the metabolism of reactive oxygen species (ROS) at the injury site of sweet potato on the first day.…”

Identification and Quantitation of the Bioactive Components in Wasted Aralia elata Leaves Extract with Endothelial Protective Activity

“…Chlorogenic acid (CGA) has been identified as a critical factor in combating oxidative stress in plants. In the autumn, plants experience various stressors such as lower temperatures, a reduced light intensity, and altered photoperiods, all of which can lead to the production of reactive oxygen species (ROS) [54,55]. Higher levels of chlorogenic acid help mitigate the damaging effects of these reactive molecules.…”