Combined application of hot water treatment and eucalyptus leaf extract postpones seneṣcence in harvested green chilies by conserving their antioxidants: a sustainable approach

Muhammad Wasim Haider; Muhammad Nafees; Rashid Iqbal; Sajid Ali; Habat Ullah Asad; Farrukh Azeem; Muhammad Arslan; Muhammad Habib Ur Rahman; Abdel-Rhman Z Gaafar; Mohamed S Elshikh

doi:10.1186/s12870-023-04588-y

Combined application of hot water treatment and eucalyptus leaf extract postpones seneṣcence in harvested green chilies by conserving their antioxidants: a sustainable approach

BMC Plant Biol. 2023 Nov 18;23(1):576. doi: 10.1186/s12870-023-04588-y.

Authors

Affiliations

¹ Department of Horticultural Sciences, The Islamia University of Bahawalpur, Bahawalpur, 63100, Pakistan. wasim.haider@iub.edu.pk.
² Department of Horticultural Sciences, The Islamia University of Bahawalpur, Bahawalpur, 63100, Pakistan.
³ Department of Agronomy, The Islamia University of Bahawalpur, Bahawalpur, 63100, Pakistan.
⁴ Department of Horticulture, Bahauddin Zakariya University, Multan, 60000, Pakistan.
⁵ Centre for Agriculture and Bioscience International, Rawalpindi, 46300, Pakistan.
⁶ Agri Development, Fauji Fresh N Freeze Ltd, Gulberg II, Lahore, 48000, Pakistan.
⁷ Institute of Crop Science and Resource Conservation (INRES), Crop Science, University of Bonn, 53115, Bonn, Germany. m.arslan@uni-bonn.de.
⁸ Institute of Crop Science and Resource Conservation (INRES), Crop Science, University of Bonn, 53115, Bonn, Germany.
⁹ Department of Seed Science and Technology, Institute of Plant Breeding and Biotechnology (IPBB), MNS-University of Agriculture, Multan, Pakistan.
¹⁰ Department of Botany and Microbiology, College of Science, King Saud University, 11451, Riyadh, Saudi Arabia.

Abstract

Background: Green chili is the predominant vegetable in tropical and subtropical regions with high economic value. However, after harvest, it exhibits vigorous metabolic activities due to the high moisture level, leading to a reduction in bioactive compounds and hence reduced shelf life and nutritional quality. Low temperature storage results in the onset of chilling injury symptoms. Therefore, developing techniques to increase the shelf life of green chilies and safeguard their nutritional value has become a serious concern for researchers. In this regard, an experiment was conducted to evaluate the impact of the alone or combined application of hot water treatment (HWT) (45 °C for 15 min) and eucalyptus leaf extract (ELE) (30%) on 'Golden Hot' chilies in comparison to the control. After treatment, chilies were stored at 20 ± 1.5 °C for 20 days.

Results: HWT + ELE-treated chilies had a significant reduction in fruit weight loss (14.6%), fungal decay index (35%), red chili percentage (41.2%), soluble solid content (42.9%), ripening index (48.9%), and reactive oxygen species production like H₂O₂ (55.1%) and O^-2 (46.5%) during shelf in comparison to control, followed by the alone application of HWT and ELE. Furthermore, the combined use of HWT and ELE effectively improved the antioxidative properties of stored chilies including DPPH radical scavenging activities (54.6%), ascorbic acid content (28.4%), phenolic content (31.8%), as well as the enzyme activities of POD (103%), CAT (128%), SOD (26.5%), and APX (43.8%) in comparison to the control. Additionally, the green chilies underwent HWT + ELE treatment also exhibited higher chlorophyll levels (100%) and general appearance (79.6%) with reduced anthocyanin content (40.8%) and wrinkling (43%), leading to a higher marketable fruit (41.3%) than the control.

Conclusion: The pre-storage application of HWT and ELE could be used as an antimicrobial, non-chemical, non-toxic, and eco-friendly treatment for preserving the postharvest quality of green chilies at ambient temperature (20 ± 1.5 °C).

Keywords: Capsicum annum L.; DPPH scavenging activities; ELE; Environment friendly; HWT; Postharvest management; Safe food additive; Storage life extension.

MeSH terms

Antioxidants* / analysis
Ascorbic Acid
Eucalyptus*
Fruit / microbiology
Hydrogen Peroxide
Plant Extracts / analysis

Substances

Antioxidants
Hydrogen Peroxide
Ascorbic Acid
Plant Extracts