Postharvest biochemical characteristics and ultrastructure of Coprinus comatus

Yi Peng; Tongling Li; Huaming Jiang; Yunfu Gu; Qiang Chen; Cairong Yang; Wei Liang Qi; Song-Qing Liu; Xiaoping Zhang

doi:10.7717/peerj.8508

Postharvest biochemical characteristics and ultrastructure of Coprinus comatus

PeerJ. 2020 Feb 5:8:e8508. doi: 10.7717/peerj.8508. eCollection 2020.

Authors

Yi Peng^{1

2}, Tongling Li², Huaming Jiang³, Yunfu Gu¹, Qiang Chen¹, Cairong Yang^{2

4}, Wei Liang Qi², Song-Qing Liu^{2

4}, Xiaoping Zhang¹

Affiliations

¹ College of Resources, Sichuan Agricultural Uniersity, Chengdu, Sichuan, China.
² College of Chemistry and Life Sciences, Chengdu Normal University, Chengdu, Sichuan, China.
³ Sichuan Vocational and Technical College, Suining, Sichuan, China.
⁴ Institute of Microbiology, Chengdu Normal University, Chengdu, Sichuan, China.

Abstract

Background: Coprinus comatus is a novel cultivated edible fungus, hailed as a new preeminent breed of mushroom. However, C. comatus is difficult to keep fresh at room temperature after harvest due to high respiration, browning, self-dissolve and lack of physical protection.

Methods: In order to extend the shelf life of C. comatus and reduce its loss in storage, changes in quality, biochemical content, cell wall metabolism and ultrastructure of C. comatus (C.c77) under 4 °C and 90% RH storage regimes were investigated in this study.

Results: The results showed that: (1) After 10 days of storage, mushrooms appeared acutely browning, cap opening and flowing black juice, rendering the mushrooms commercially unacceptable. (2) The activity of SOD, CAT, POD gradually increased, peaked at the day 10, up to 31.62 U g^-1 FW, 16.51 U g^-1 FW, 0.33 U g^-1 FW, respectively. High SOD, CAT, POD activity could be beneficial in protecting cells from ROS-induced injuries, alleviating lipid peroxidation and stabilizing membrane integrity. (3) The activities of chitinase, β-1,3-glucanase were significantly increased. Higher degrees of cell wall degradation observed during storage might be due to those enzymes' high activities. (4) The fresh C. comatus had dense tissue and every single cell had the number of intracellular organelles which structure can be observed clearly. After 10 d storage, the number of intracellular organelles was declined and the structure was fuzzy, the nucleus disappeared. After 20 d storage, C. comatus's organization was completely lost, many cells were stacked together and the cell wall was badly damaged.

Keywords: Browning; CAT; Cell degradation; Chicken drumstick mushroom; Glucanase; PG; POD; Postharvest storage; SOD; TEM.

Grants and funding

This work was financially supported by the Technology of Sichuan Province (No. 2016NFP0091) and the National Natural Science Foundation (No. 31870309). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.