High-Temperature Induced Changes of Extracellular Metabolites in Pleurotus ostreatus and Their Positive Effects on the Growth of Trichoderma asperellum

Abstract

Pleurotus ostreatus is a widely cultivated edible fungus in China. Green mold disease of P. ostreatus which can seriously affect yield is a common disease during cultivation. It occurs mostly after P. ostreatus mycelia have been subjected to high temperatures. However, little information is available on the relationship between high temperature and green mold disease. The aim of this study is to prove that extracellular metabolites of P. ostreatus affected by high temperature can promote the growth of Trichoderma asperellum. After P. ostreatus mycelia was subjected to high temperature, the extracellular fluid of P. ostreatus showed a higher promoting effect on mycelial growth and conidial germination of T. asperellum. The thiobarbituric acid reactive substance (TBARS) content reached the maximum after 48 h at 36°C. A comprehensive metabolite profiling strategy involving gas chromatography-mass spectrometry (GC/MS) combined with liquid chromatography-mass spectrometry (LC/MS) was used to analyze the changes of extracellular metabolites in response to high temperature. A total of 141 differential metabolites were identified, including 84.4% up-regulated and 15.6% down-regulated. Exogenous metabolites whose concentrations were increased after high temperature were randomly selected, and nearly all of them were able to promote the mycelial growth and conidial germination of T. asperellum. The combination of all selected exogenous metabolites also has the promotion effects on the mycelial growth and conidial germination of T. asperellum in a given concentration range in vitro. Overall, these results provide a first view that high temperature affects the extracellular metabolites of P. ostreatus, and the extensive change in metabolites promotes T. asperellum growth.

Development of antimicrobial therapy methods to overcome the antibiotic resistance of Acinetobacter baumannii

“…As the incidence and mortality rate of MDR pathogens increase, interest in bacteriophages is returning all over the world. Since 2010, scientists from different countries have discovered new bacteriophages infecting MDR A. baumannii [ 43 - 46 ]. In most cases, bacteriophages against A. baumannii have been studied in vitro , but the ability of bacteriophages to lyse A. baumannii has recently increasingly come to be evaluated by simulating the infectious process in vivo .…”

“…Less than 20% of Galleria mellonella larvae survived 96 h after infection with A. baumannii. With the introduction of bacteriophages, larval survival increased to 75%, while treatment with polymyxin B increased survival to only 25% [ 47 ]. Improvement in wound infection healing in the phage-infected group and a significant reduction in mortality in rats, compared to infected animals treated with an antibiotic, was also observed [ 48 ].…”

“…Chimeric AMPs created from two different AMPs were shown to improve antimicrobial activity. Other successful examples of AMPs modification include substitutions with D-amino acids, β-naphthylalanine, and α,α-dialkyl amino acids [ 75 ]. A panel of synthetic peptides was obtained based on human LL-37 AMP [ 76 ].…”

Metabolic Profiling of Pleurotus tuoliensis During Mycelium Physiological Maturation and Exploration on a Potential Indicator of Mycelial Maturation

“…Mycelial extract was prepared according to the protocol reported by Qiu et al (2018). 60 mg of accurately weighed sample were transferred to a 1.5-mL Eppendorf tube and mixed with 360 μL of cold methanol and 40 μL of 2-chloro-l-phenylalanine (0.3 mg/mL) dissolved in methanol as internal standard.…”

“…GC-MS technology has been used to identify metabolites that can be used as markers for A. bisporus injury (O’Gorman et al, 2012). Qiu et al (2018) used GC-MS and LC-MS to analyze changes in extracellular metabolites in the mycelium of P. ostreatus under high temperature conditions, as well as to study the effect of exogenous addition of some significantly increased metabolites on the growth of Trichoderma asperellum , with the goal of determining why P. ostreatus was easily infected by T . asperellum .…”