Changes in Metabolisms of Antioxidant and Cell Wall in Three Pummelo Cultivars during Postharvest Storage

Abstract

The juice sacs of pummelo fruit is susceptible to softening during storage at 25 °C, which causes quality deterioration and flavor loss during postharvest pummelo storage. This study investigated the changes in metabolisms of antioxidant and cell wall in juice sacs of three pummelo cultivars—Hongroumiyou (HR), Bairoumiyou (BR) and Huangroumiyou (HuR)—during postharvest storage. The results revealed that, with the extension of storage, the juice sacs of three pummelo cultivars exhibited a decrease in total antioxidant capacity (TAC), DPPH and ABTS radical scavenging activity; a decline in total phenols (TP) content and an increase firstly then a decrease in total ascorbic acid (TAA) content; and a decrease in lipoxygenase (LOX) activity and a rise initially, but a decline in activities of ascorbate peroxidase (APX) and glutathione peroxidase (GPX). Additionally, increased water-soluble pectin (WSP), but declined propectin, ionic-soluble pectin (ISP) and chelator-soluble pectin (CSP); as well as an increase from 0 d to 60 d then followed by a decline in activities of pectinesterase (PE), polygalacturonase (PG) and pectate lyase (PL) were observed. These results suggested that the metabolisms of antioxidant and cell wall could result in softening and senescence of pummelo fruit.

Integrative Analysis of the lncRNA and mRNA Transcriptome Revealed Genes and Pathways Potentially Involved in the Anther Abortion of Cotton (Gossypium hirsutum L.)

“…This showed that mitochondrial respiratory-related enzymes play an important role in the regulation of the CMS line C2P5A, and this result is consistent with a previous study in CMS plants [85][86][87]. Pectinesterase is a wall-degrading enzyme, and abnormal expression may lead to the disruption of the cell wall structure in the CMS line C2P5A; a previous study demonstrated that pectinesterase plays a major role in the plant [88]. In our research, the GO of the cytoplasm was significant, showing that its abnormality may be one of the key factors leading to abortion in the CMS line C2P5A compared to the maintainer line C2P5B.…”

1H NMR-Based Metabolic Profiling to Follow Changes in Pomelo Cultivars during Postharvest Senescence

“…Our previous work revealed that lignin accumulation was closely associated with energy metabolism, lipid peroxidation and sugar metabolism [3,4]. In addition to lignification, softening is also significant in pomelo fruit, which was reinforced by the observation that antioxidant and cell wall metabolisms could result in softening and senescence of pummelo fruit, as described in our previous work [5]. In addition to granulation, lignification and softening, another undesirable trait in postharvest pomelo fruit is the variable taste and flavor.…”

The Involvement of Energy Metabolism and Lipid Peroxidation in Lignin Accumulation of Postharvest Pumelos

“…Interestingly, the scavenging rate of –OH showed a gradual increasing tendency in the earlier and middle storage period and a subsequent decline in the later storage period ( Figure 4 D). In our previous study, the activities of APX and GPX played a role in scavenging the ROS in postharvest pumelo fruit [ 69 ]. Furthermore, there was a sharp increment of lignin content in HR pumelo fruit in the later storage stage ( Supplementary Figure S1 ), which was in accordance with dysfunction of the ROS scavenging system during this stage ( Figure 4 ).…”