Low Temperature (15 °C) Reduces Bacterial Diversity and Prolongs the Preservation Time of <i>Volvariella volvacea</i>

• Main Authors: Xiuling Wang, Shunjie Liu, Mingjie Chen, Changxia Yu, Yan Zhao, Huanling Yang, Lei Zha, Zhengpeng Li
• Format: Article
• Language: English
• Published: MDPI AG 2019-10-01
• Series: Microorganisms
• Subjects: <i>volvariella volvacea</i>; food preservation; bacterial community; <i>firmicutes</i>; <i>solibacillus</i>
• Online Access: https://www.mdpi.com/2076-2607/7/10/475

Straw mushroom (<i>Volvariella volvacea</i>) is the most commonly cultivated edible fungus in the world, but the challenges associated with the preservation have limited its marketability. Microbiology, especially bacteria, play a key role in the deterioration of food, this study aimed to reveal the succession of the bacterial community on the surfaces of <i>V. volvacea</i> fruit bodies under different temperature conditions. We amplified 16S rRNA genes of V4 regions, obtained the bacterial species information by using high-throughput sequencing technology, and analyzed the effects of environmental temperature and preservation time on bacterial communities. The relative abundances of <i>Firmicutes</i>, <i>Bacilli</i>, and <i>Bacillales</i> increased significantly when straw mushrooms began to rot. Furthermore, the relative abundances of <i>Paenibacillus</i>, <i>Lysinibacillus</i> and <i>Solibacillus,</i> which belong to <i>Bacillales</i>, increased with the decay of straw mushroom. The Shannon and Simpson indices of <i>V. volvacea</i> stored at 30 &#176;C were significantly higher than those of <i>V. volvacea</i> stored at 15 &#176;C, which indicates that a high temperature contributes to the improvement in the species diversity. According to the linear discriminant analysis (LDA) effect size (LEfSe) results, the number of biomarkers in the 30 &#176;C group (32, 42.11%) was significantly higher than that in the 15 &#176;C group (17, 22.37%), indicating that a high temperature has a clustering effect on some bacterial communities. A Spearman correlation analysis showed that <i>Pseudomonas</i>, <i>Stenotrophomonas</i> and <i>Solibacillus</i> promoted the decay of straw mushroom. In conclusion, a high temperature increases the bacterial diversity on the straw mushroom surfaces and has a clustering effect on the bacterial communities. The bacterial community consisting of <i>Firmicutes</i>, <i>Bacilli</i>, <i>Bacillales</i>, <i>Paenibacillus</i>, <i>Lysinibacillus</i>, <i>Pseudomonas</i>, <i>Stenotrophomonas</i> and <i>Solibacillus</i> could promote the decay of straw mushroom, so new preservation materials research can focus on inhibiting anaerobic and decay-causing bacteria to prolong preservation time.