Hydrogen Sulfide Mitigates Chilling Injury of Postharvest Banana Fruits by Regulating γ-Aminobutyric Acid Shunt Pathway and Ascorbate-Glutathione Cycle

Sajid Ali; Aamir Nawaz; Safina Naz; Shaghef Ejaz; Mehdi Maqbool; Manzer H Siddiqui; Hazem M Kalaji; Jacek Wróbel; Arkadiusz Telesiński; Alicja Auriga

doi:10.3389/fpls.2022.941246

Hydrogen Sulfide Mitigates Chilling Injury of Postharvest Banana Fruits by Regulating γ-Aminobutyric Acid Shunt Pathway and Ascorbate-Glutathione Cycle

Front Plant Sci. 2022 Jul 5:13:941246. doi: 10.3389/fpls.2022.941246. eCollection 2022.

Authors

Affiliations

¹ Department of Horticulture, Faculty of Agricultural Sciences and Technology, Bahauddin Zakariya University, Multan, Pakistan.
² Department of Horticulture, University of Poonch Rawalakot, Rawalakot, Pakistan.
³ Department of Botany and Microbiology, College of Science, King Saud University, Riyadh, Saudi Arabia.
⁴ Institute of Technology and Life Sciences - National Research Institute, Falenty, Poland.
⁵ Department of Plant Physiology, Institute of Biology, Warsaw University of Life Sciences - SGGW, Warsaw, Poland.
⁶ Department of Bioengineering, West Pomeranian University of Technology, Szczecin, Poland.
⁷ Department of Animal Anatomy and Zoology, Faculty of Biotechnoology and Animal Husbandary, West Pomeranin University of Technology, Szczecin, Poland.

Abstract

This study aimed to determine the effect of hydrogen sulfide on chilling injury (CI) of banana (Musa spp.) during cold storage (7°C). It was observed that hydrogen sulfide application (2 mmol L^-1) markedly reduced the CI index and showed significantly higher chlorophyll contents, along with suppressed chlorophyll peroxidase and chlorophyllase enzyme activity. The treated banana fruits exhibited substantially higher peel lightness (L*), along with significantly a lower browning degree and soluble quinone content. The treated bananas had substantially a higher endogenous hydrogen sulfide content and higher activity of its biosynthesis-associated enzymes such as D-cysteine desulfhydrase (DCD) and L-cysteine desulfhydrase (LCD), along with significantly lower ion leakage, lipid peroxidation, hydrogen peroxide, and superoxide anion concentrations. Hydrogen sulfide-treated banana fruits showed an increased proline content and proline metabolism-associated enzymes including ornithine aminotransferase (OAT), Δ¹-pyrroline-5-carboxylate synthetase (P5CS), and proline dehydrogenase (PDH). In the same way, hydrogen sulfide-fumigated banana fruits accumulated higher endogenous γ-aminobutyric acid (GABA) due to enhanced activity of glutamate decarboxylase (GAD) and GABA transaminase (GABA-T) enzymes. The hydrogen sulfide-treated fruits exhibited higher total phenolics owing to lower polyphenol oxidase (PPO) and peroxidase (POD) activity and stimulated phenylalanine ammonia lyase (PAL). The treated banana exhibited higher ascorbate peroxidase (APX), catalase (CAT), glutathione reductase (GR), dehydroascorbate reductase (DHAR), monodehydroascorbate reductase (MDHAR), and superoxide dismutase (SOD) activity, along with higher glutathione (GSH) and ascorbic acid (AsA) concentrations and a significantly lower dehydroascorbic acid (DHA) content. In conclusion, hydrogen sulfide treatment could be utilized for CI alleviation of banana fruits during cold storage.

Keywords: antioxidant activities; chilling injury; cold storage; lipid peroxidation; proline accumulation.