Physio-biochemical Responses of Okra (<i>Abelmoschus esculentus</i>) to Oxidative Stress Under Low Temperature Storage
Okra pods, commonly eaten at an immature stage, undergo quick postharvest deterioration due to high respiration, water loss, wilting, toughening and decay. As okra is a tropical crop, its pods are susceptible to chilling injury (CI) at low storage temperatures. The effects of low temperature stora...
Saved in:
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
The Japanese Society for Horticultural Science
2020
|
| Subjects: | |
| Online Access: | http://ir.unimas.my/id/eprint/38233/1/Physio-biochemical%20Responses%20of%20Okra.pdf http://ir.unimas.my/id/eprint/38233/ https://www.jstage.jst.go.jp/article/hortj/89/1/89_UTD-105/_article |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Institution: | Universiti Malaysia Sarawak |
| Language: | English |
| Summary: | Okra pods, commonly eaten at an immature stage, undergo quick postharvest deterioration due to high
respiration, water loss, wilting, toughening and decay. As okra is a tropical crop, its pods are susceptible to
chilling injury (CI) at low storage temperatures. The effects of low temperature storage on the physiobiochemical properties of okra pods were determined. Chilling injury symptoms were found only in pods
stored at 4°C and were more apparent after transfer to 25°C. In seeds, the CI index was positively correlated
with seed browning, H2O2
, malondialdehyde (MDA) content, and catalase (CAT) activity. Chilling-injured
seeds had lower total phenolic content (TPC), antioxidant activity (DPPH scavenging activity and FRAP
assay), peroxidase (POD), and superoxide dismutase (SOD) activities than non-injured seeds. Additionally, the
seed browning index was related to high polyphenol oxidase (PPO) activity. In the pericarp, the CI index was
also positively correlated with the H2O2
and MDA contents. The POD and SOD activities in chilling-injured
pericarp were significantly lower than in non-injured pericarp. Chilling injury resulted in an initial increase in
DPPH scavenging and CAT activities which later decreased as CI became severe. These results indicate that CI
in okra is due to accumulation of H2O2
, and MDA, as well as its weak antioxidant defense mechanism. This
resulted in development of CI symptoms, including seed browning. |
|---|