Trichoderma harzianum metabolites disturb Fusarium culmorum metabolism: Metabolomic and proteomic studies

A Novel Dry-Cured Ham Broth-Derived Peptide JHBp2 Effectively Inhibits Salmonella typhimurium In Vitro: Integrated Metabolomic, Proteomic, and Molecular Simulation Analyses

JHBp2 is a peptide purified from Jinhua ham broth with antibacterial activity against Salmonella typhimurium. Untargeted metabolomics and label-free quantitative proteomics were used to analyze metabolic and protein expression changes in S. typhimurium after JHBp2 treatment. Cell wall and membrane damage results indicate that JHBp2 has membrane-disruptive properties, causing leakage of intracellular nucleic acids and proteins. Metabolomics revealed 516 differentially expressed metabolites, involving cofactor biosynthesis, purine metabolism, ABC transporters, glutathione metabolism, pyrimidine metabolism, etc. Proteomics detected 735 differentially expressed proteins, involving pyruvate metabolism, amino acid biosynthesis, purine metabolism, carbon metabolism, glycolysis/gluconeogenesis, etc. RT-qPCR and proteomics results showed a positive correlation, and molecular docking demonstrated stable binding of JHBp2 to some differentially expressed proteins. In summary, JHBp2 could disrupt the S. typhimurium cell wall and membrane structure, interfere with synthesis of membrane-related proteins, trigger intracellular substance leak, and reduce levels of enzymes and metabolites involved in energy metabolism, amino acid anabolism, and nucleotide anabolism.

Cultivating a greener future: Exploiting trichoderma derived secondary metabolites for fusarium wilt management in peas

This study aimed to identify efficient Trichoderma isolate(s) for the management of Fusarium wilt in peas. Four different pea germplasms (Sarsabz, Pea-09, Meteor and Supreme) were evaluated for resistance against Fusarium oxysporum in pot assay. Resistant germplasm exhibits a varying range of disease severity (23%) and percent disease index (21%), whereas susceptible and highly susceptible germplasm exhibit maximum disease severity (44-79%) and percent disease index (47-82%). The susceptible germplasm Meteor was selected for in vivo experiment. Five different Trichoderma spp. (Trichoderma koningii, T. hamatum, T. longibrachiatum, T. viride, and T. harzianum) were screened for the production of hydrolytic extracellular enzymes under in vitro. In-vitro biocontrol potential of Trichoderma spp. was assayed by percentage inhibition of dry mass of Fusarium oxysporum pisi (FOP) with Trichoderma spp. metabolite filtrate concentrations. Maximum growth inhibition was observed by T. harzianum (50-89%). T. harzianum metabolites in filtrate conc. (40%, 50%, and 60%) exhibited maximum reduction in biomass and were thus used for in vivo management of the disease. The pot experiment for in-vivo management also confirmed the maximum inhibition of FOP by T. harzianum metabolites filtrate at 60% by reducing disease parameters and enhancing growth, yield, and physiochemical and stress markers. Trichoderma strains led to an increase in chlorophyll and carotenoids (34-26%), Total phenolic 55%, Total protein content 60%, Total Flavonoid content 36%, and the increasing order of enzyme activities were as follows: CAT > POX > PPO > PAL in all treatments. These strains demonstrate excellent bio-control of Fusarium wilt in pea via induction of defense-related enzymes. The present work will help use Trichoderma species in disease management programme as an effective biocontrol agent against plant pathogens.

Antagonistic properties against Fusarium sporotrichioides and glycosylation of HT-2 and T-2 toxins by selected Trichoderma strains

The present study assessed the ability of Trichoderma to combat F. sporotrichioides, focusing on their antagonistic properties. Tests showed that Trichoderma effectively inhibited F. sporotrichioides mycelial growth, particularly with T. atroviride strains. In co-cultures on rice grains, Trichoderma almost completely reduced the biosynthesis of T-2 and HT-2 toxins by Fusarium. T-2 toxin-α-glucoside (T-2-3α-G), HT-2 toxin-α-glucoside (HT-2-3α-G), and HT-2 toxin-β-glucoside (HT-2-3β-G) were observed in the common culture medium, while these substances were not present in the control medium. The study also revealed unique metabolites and varying metabolomic profiles in joint cultures of Trichoderma and Fusarium, suggesting complex interactions. This research offers insights into the processes of biocontrol by Trichoderma, highlighting its potential as a sustainable solution for managing cereal plant pathogens and ensuring food safety.

Adaptation of the metolachlor-degrading fungus Trichoderma harzianum to the simultaneous presence of low-density polyethylene (LDPE) microplastics

Although it is known that microplastics (MPs) in soils cause a threat to this complex environment, the actual effects of MPs on soil microorganisms and their catabolic activities, particularly with the biodegradation of herbicides, remain unclear. Hence, the objective of this study was to investigate the effects of a simultaneous presence of metolachlor and low-density polyethylene (LDPE) microplastics on growth inhibition and adaptive responses of Trichoderma harzianum in soil microcosms. Using ergosterol content as an indicator of fungal biomass, it was observed that MPs alone had a marginal inhibitory effect on the growth of the fungus, whereas MET exhibited a dose-dependent inhibitory effect on T. harzianum. However, the presence of MPs did not influence the fungal transforming activity toward the herbicide. Conversely, analysis of lipid profiles in the presence of MPs and herbicides revealed a reduction in the overall fluidity of phospholipid fatty acids, primarily attributed to an increase in lysophospholipids. The activities of six extracellular enzymes in the soil, measured using methylumbelliferone-linked substrates, were significantly enhanced in the presence of MET. These findings contribute to a broader understanding of the alterations in fungal activity in soil resulting from the influence of MPs and MET.

Titanium biogenic nanoparticles to help the growth of Trichoderma harzianum to be used in biological control

BACKGROUND

The biogenic synthesis of metallic nanoparticles is a green alternative that reduces the toxicity of this nanomaterials and may enable a synergy between the metallic core and the biomolecules employed in the process enhancing biological activity. The aim of this study was to synthesize biogenic titanium nanoparticles using the filtrate of the fungus Trichoderma harzianum as a stabilizing agent, to obtain a potential biological activity against phytopathogens and mainly stimulate the growth of T. harzianum, enhancing its efficacy for biological control.

RESULTS

The synthesis was successful and reproductive structures remained in the suspension, showing faster and larger mycelial growth compared to commercial T. harzianum and filtrate. The nanoparticles with residual T. harzianum growth showed inhibitory potential against Sclerotinia sclerotiorum mycelial growth and the formation of new resistant structures. A great chitinolytic activity of the nanoparticles was observed in comparison with T. harzianum. In regard to toxicity evaluation, an absence of cytotoxicity and a protective effect of the nanoparticles was observed through MTT and Trypan blue assay. No genotoxicity was observed on V79-4 and 3T3 cell lines while HaCat showed higher sensitivity. Microorganisms of agricultural importance were not affected by the exposure to the nanoparticles, however a decrease in the number of nitrogen cycling bacteria was observed. In regard to phytotoxicity, the nanoparticles did not cause morphological and biochemical changes on soybean plants.

CONCLUSION

The production of biogenic nanoparticles was an essential factor in stimulating or maintaining structures that are important for biological control, showing that this may be an essential strategy to stimulate the growth of biocontrol organisms to promote more sustainable agriculture.

Strain improvement of Trichoderma harzianum for enhanced biocontrol capacity: Strategies and prospects

In the control of plant diseases, biocontrol has the advantages of being efficient and safe for human health and the environment. The filamentous fungus Trichoderma harzianum and its closely related species can inhibit the growth of many phytopathogenic fungi, and have been developed as commercial biocontrol agents for decades. In this review, we summarize studies on T. harzianum species complex from the perspective of strain improvement. To elevate the biocontrol ability, the production of extracellular proteins and compounds with antimicrobial or plant immunity-eliciting activities need to be enhanced. In addition, resistance to various environmental stressors should be strengthened. Engineering the gene regulatory system has the potential to modulate a variety of biological processes related to biocontrol. With the rapidly developing technologies for fungal genetic engineering, T. harzianum strains with increased biocontrol activities are expected to be constructed to promote the sustainable development of agriculture.

Trichoderma versus Fusarium-Inhibition of Pathogen Growth and Mycotoxin Biosynthesis

This study evaluated the ability of selected strains of Trichoderma viride, T. viridescens, and T. atroviride to inhibit mycelium growth and the biosynthesis of mycotoxins deoxynivalenol (DON), nivalenol (NIV), zearalenone (ZEN), α-(α-ZOL) and β-zearalenol (β-ZOL) by selected strains of Fusarium culmorum and F. cerealis. For this purpose, an in vitro experiment was carried out on solid substrates (PDA and rice). After 5 days of co-culture, it was found that all Trichoderma strains used in the experiment significantly inhibited the growth of Fusarium mycelium. Qualitative assessment of pathogen-antagonist interactions showed that Trichoderma colonized 75% to 100% of the medium surface (depending on the species and strain of the antagonist and the pathogen) and was also able to grow over the mycelium of the pathogen and sporulate. The rate of inhibition of Fusarium mycelium growth by Trichoderma ranged from approximately 24% to 66%. When Fusarium and Trichoderma were co-cultured on rice, Trichoderma strains were found to inhibit DON biosynthesis by about 73% to 98%, NIV by about 87% to 100%, and ZEN by about 12% to 100%, depending on the pathogen and antagonist strain. A glycosylated form of DON was detected in the co-culture of F. culmorum and Trichoderma, whereas it was absent in cultures of the pathogen alone, thus suggesting that Trichoderma is able to glycosylate DON. The results also suggest that a strain of T. viride is able to convert ZEN into its hydroxylated derivative, β-ZOL.

Effects of Trichoderma harzianum biofertilizer on growth, yield, and quality of Bupleurum chinense

The use of chemical fertilizers and pesticides led to a decline in the quality and yield of Bupleurum chinense. The aim of this study was to determine the effects of Trichoderma harzianum biofertilizer on the growth, yield, and quality of radix bupleuri and microbial responses. The results showed that T. harzianum biofertilizer promoted the growth of B. chinense and increased the yield and quality of radix bupleuri. In addition, it increased the contents of NH₄ ⁺-N, NO₃ ^--N, available K, and available P and increased the activities of sucrase and catalase in the rhizosphere soil. High-throughput analysis showed that the dominant bacteria in the rhizosphere were Proteobacteria (28%), Acidobacteria (23%), and Actinobacteria (17%), whereas the dominant fungi were Ascomycota (49%), Zygomycota (30%), and Basidiomycota (6%). After the application of T. harzianum biofertilizer, the abundance of Proteobacteria and Actinobacteria (relative to total bacteria) and Ascomycota and Basidiomycota (relative to total fungi) increased, but the relative abundance of Acidobacteria decreased. Canonical correlation analysis (CCA) showed that the relative abundance of Pseudarthrobacter, Streptomyces, Rhizobium, Nocardioides, Minimedusa, and Chaetomium were positively correlated with NO₃ ^--N, NH₄ ⁺-N, available K, available P, sucrase, and catalase in microbial communities, whereas Aeromicrobium and Mortierella were positively correlated with soil organic matter and urease. These results suggest that T. harzianum biofertilizer could significantly improve the yield and quality of radix bupleuri by changing the structure of soil microbial flora and soil enzyme activity. Therefore, it could be recommended for commercial scale production of Bupleurum.

Cyanobacterial secondary metabolites towards improved commercial significance through multiomics approaches

Cyanobacteria are ubiquitous photosynthetic prokaryotes responsible for the oxygenation of the earth's reducing atmosphere. Apart from oxygen they are producers of a myriad of bioactive metabolites with diverse complex chemical structures and robust biological activities. These secondary metabolites are known to have a variety of medicinal and therapeutic applications ranging from anti-microbial, anti-viral, anti-inflammatory, anti-cancer, and immunomodulating properties. The present review discusses various aspects of secondary metabolites viz. biosynthesis, types and applications, which highlights the repertoire of bioactive constituents they harbor. Majority of these products have been produced from only a handful of genera. Moreover, with the onset of various OMICS approaches, cyanobacteria have become an attractive chassis for improved secondary metabolites production. Also the intervention of synthetic biology tools such as gene editing technologies and a variety of metabolomics and fluxomics approaches, used for engineering cyanobacteria, have significantly enhanced the production of secondary metabolites.

Potential of Trichoderma harzianum and Its Metabolites to Protect Wheat Seedlings against Fusarium culmorum and 2,4-D

Wheat is a critically important crop. The application of fungi, such as Trichoderma harzianum, to protect and improve crop yields could become an alternative solution to synthetic chemicals. However, the interaction between the fungus and wheat in the presence of stress factors at the molecular level has not been fully elucidated. In the present work, we exposed germinating seeds of wheat (Triticum aestivum) to the plant pathogen Fusarium culmorum and the popular herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) in the presence of T. harzianum or its extracellular metabolites. Then, the harvested roots and shoots were analyzed using spectrometry, 2D-PAGE, and MALDI-TOF/MS techniques. Although F. culmorum and 2,4-D were found to disturb seed germination and the chlorophyll content, T. harzianum partly alleviated these negative effects and reduced the synthesis of zearalenone by F. culmorum. Moreover, T. harzianum decreased the activity of oxidoreduction enzymes (CAT and SOD) and the contents of the oxylipins 9-Hode, 13-Hode, and 13-Hotre induced by stress factors. Under the influence of various growth conditions, changes were observed in over 40 proteins from the wheat roots. Higher volumes of proteins and enzymes performing oxidoreductive functions, such as catalase, ascorbate peroxidase, cytochrome C peroxidase, and Cu/Zn superoxide dismutase, were found in the Fusarium-inoculated and 2,4-D-treated wheat roots. Additionally, observation of the level of 12-oxo-phytodienoic acid reductase involved in the oxylipin signaling pathway in wheat showed an increase. Trichoderma and its metabolites present in the system leveled out the mentioned proteins to the control volumes. Among the 30 proteins examined in the shoots, the expression of the proteins involved in photosynthesis and oxidative stress response was found to be induced in the presence of the herbicide and the pathogen. In summary, these proteomic and metabolomic studies confirmed that the presence of T. harzianum results in the alleviation of oxidative stress in wheat induced by 2,4-D or F. culmorum.