scholarly journals Potentiated inhibition of Trichoderma virens and other environmental fungi by new biocide combinations

2021 ◽  
Author(s):  
Cindy Vallières ◽  
Cameron Alexander ◽  
Simon V. Avery
Keyword(s):  
Growth Inhibition ◽  
Mammalian Cells ◽  
Low Cost ◽  
Fungal Growth ◽  
Trichoderma Virens ◽  
Synthetic Materials ◽  
Test Organisms ◽  
Development Risks ◽  
Fungal Growth Inhibition ◽  
High Throughput Assay

Abstract Fungi cause diverse, serious socio-economic problems, including biodeterioration of valuable products and materials that spawns a biocides industry worth ~$11 billion globally. To help combat environmental fungi that commonly colonise material products, this study tested the hypothesis that combination of an approved fungicide with diverse agents approved by the FDA (Food and Drug Administration) could reveal potent combinatorial activities with promise for fungicidal applications. The strategy to use approved compounds lowers potential development risks for any effective combinations. A high-throughput assay of 1280 FDA-approved compounds was conducted to find those that potentiate the effect of iodopropynyl-butyl-carbamate (IPBC) on the growth of Trichoderma virens; IPBC is one of the two most widely used Biocidal Products Regulations–approved fungicides. From this library, 34 compounds in combination with IPBC strongly inhibited fungal growth. Low-cost compounds that gave the most effective growth inhibition were tested against other environmental fungi that are standard biomarkers for resistance of synthetic materials to fungal colonisation. Trifluoperazine (TFZ) in combination with IPBC enhanced growth inhibition of three of the five test fungi. The antifungal hexetidine (HEX) potentiated IPBC action against two of the test organisms. Testable hypotheses on the mechanisms of these combinatorial actions are discussed. Neither IPBC + TFZ nor IPBC + HEX exhibited a combinatorial effect against mammalian cells. These combinations retained strong fungal growth inhibition properties after incorporation to a polymer matrix (alginate) with potential for fungicide delivery. The study reveals the potential of such approved compounds for novel combinatorial applications in the control of fungal environmental opportunists. Key points • Search with an approved fungicide to find new fungicidal synergies in drug libraries. • New combinations inhibit growth of key environmental fungi on different matrices. • The approach enables a more rapid response to demand for new biocides.

Fungal Growth Inhibition by Cheese Prepared Using Milk-clotting Crude Enzymes from the Edible Mushroom Hericium erinaceum

2020 ◽  
Vol 26 (1) ◽  
pp. 93-99
Author(s):  
Munekazu Kishimoto ◽  
Kazuo Nakamura ◽  
Takuto Tasaki ◽  
Kinya Matsumoto ◽  
Rina Nakano ◽  
...  
Keyword(s):  
Growth Inhibition ◽  
Fungal Growth ◽  
Edible Mushroom ◽  
Milk Clotting ◽  
Hericium Erinaceum ◽  
Fungal Growth Inhibition

scholarly journals Novel Bifunctional Inhibitor of Xylanase and Aspartic Protease: Implications for Inhibition of Fungal Growth

2001 ◽  
Vol 45 (7) ◽  
pp. 2008-2017 ◽  
Author(s):  
Chandravanu Dash ◽  
Absar Ahmad ◽  
Devyani Nath ◽  
Mala Rao
Keyword(s):  
Growth Inhibition ◽  
Fungal Growth ◽  
Phytopathogenic Fungi ◽  
Aspartic Protease ◽  
Cellular Growth ◽  
Alternative Mechanism ◽  
Trinitrobenzenesulfonic Acid ◽  
Woodward’S Reagent K ◽  
Bifunctional Inhibitor ◽  
Fungal Growth Inhibition

ABSTRACT A novel bifunctional inhibitor (ATBI) from an extremophilicBacillus sp. exhibiting an activity against phytopathogenic fungi, including Alternaria, Aspergillus, Curvularia, Colletotricum, Fusarium, and Phomopsis species, and the saprophytic fungus Trichoderma sp. has been investigated. The 50% inhibitory concentrations of ATBI ranged from 0.30 to 5.9 μg/ml, whereas the MIC varied from 0.60 to 3.5 μg/ml for the fungal growth inhibition. The negative charge and the absence of periodic secondary structure in ATBI suggested an alternative mechanism for fungal growth inhibition. Rescue of fungal growth inhibition by the hydrolytic products of xylanase and aspartic protease indicated the involvement of these enzymes in cellular growth. The chemical modification of Asp or Glu or Lys residues of ATBI by 2,4,6-trinitrobenzenesulfonic acid and Woodward's reagent K, respectively, abolished its antifungal activity. In addition, ATBI also inhibited xylanase and aspartic protease competitively, withKi values 1.75 and 3.25 μM, respectively. Our discovery led us to envisage a paradigm shift in the concept of fungal growth inhibition for the role of antixylanolytic activity. Here we report for the first time a novel class of antifungal peptide, exhibiting bifunctional inhibitory activity.

scholarly journals Competitive Exclusion Is a Major Bioprotective Mechanism of Lactobacilli against Fungal Spoilage in Fermented Milk Products

2020 ◽  
Vol 86 (7) ◽  
Author(s):  
Solvej Siedler ◽  
Martin Holm Rau ◽  
Susanne Bidstrup ◽  
Justin M. Vento ◽  
Stina Dissing Aunsbjerg ◽  
...  
Keyword(s):  
Growth Inhibition ◽  
Dairy Products ◽  
Molecular Mechanisms ◽  
Competitive Exclusion ◽  
Defense Mechanism ◽  
Fungal Growth ◽  
Fermented Milk ◽  
Attractive Alternative ◽  
Spoilage Yeast ◽  
Fungal Growth Inhibition

ABSTRACT A prominent feature of lactic acid bacteria (LAB) is their ability to inhibit growth of spoilage organisms in food, but hitherto research efforts to establish the mechanisms underlying bioactivity focused on the production of antimicrobial compounds by LAB. We show, in this study, that competitive exclusion, i.e., competition for a limited resource by different organisms, is a major mechanism of fungal growth inhibition by lactobacilli in fermented dairy products. The depletion of the essential trace element manganese by two Lactobacillus species was uncovered as the main mechanism for growth inhibition of dairy spoilage yeast and molds. A manganese transporter (MntH1), representing one of the highest expressed gene products in both lactobacilli, facilitates the exhaustive manganese scavenging. Expression of the mntH1 gene was found to be strain dependent, affected by species coculturing and the growth phase. Further, deletion of the mntH1 gene in one of the strains resulted in a loss of bioactivity, proving this gene to be important for manganese depletion. The presence of an mntH gene displayed a distinct phylogenetic pattern within the Lactobacillus genus. Moreover, assaying the bioprotective ability in fermented milk of selected lactobacilli from 10 major phylogenetic groups identified a correlation between the presence of mntH and bioprotective activity. Thus, manganese scavenging emerges as a common trait within the Lactobacillus genus, but differences in expression result in some strains showing more bioprotective effect than others. In summary, competitive exclusion through ion depletion is herein reported as a novel mechanism in LAB to delay the growth of spoilage contaminants in dairy products. IMPORTANCE In societies that have food choices, conscious consumers demand natural solutions to keep their food healthy and fresh during storage, simultaneously reducing food waste. The use of “good bacteria” to protect food against spoilage organisms has a long, successful history, even though the molecular mechanisms are not fully understood. In this study, we show that the depletion of free manganese is a major bioprotective mechanism of lactobacilli in dairy products. High manganese uptake and intracellular storage provide a link to the distinct, nonenzymatic, manganese-catalyzed oxidative stress defense mechanism, previously described for certain lactobacilli. The evaluation of representative Lactobacillus species in our study identifies multiple relevant species groups for fungal growth inhibition via manganese depletion. Hence, through the natural mechanism of nutrient depletion, the use of dedicated bioprotective lactobacilli constitutes an attractive alternative to artificial preservation.

scholarly journals An automated quantitative assay for fungal growth inhibition

1990 ◽  
Vol 69 (1-2) ◽  
pp. 55-59 ◽  
Author(s):  
Willem F. Broekaert ◽  
Frankt R.G. Terras ◽  
Bruno P.A. Cammue ◽  
Jos Vanderleyden
Keyword(s):  
Growth Inhibition ◽  
Fungal Growth ◽  
Quantitative Assay ◽  
Fungal Growth Inhibition

scholarly journals Effect of volatile organic compounds mediated fungal growth inhibition by Trichoderma asperellum HbGT6-07

2021 ◽  
Author(s):  
Md Kamaruzzaman ◽  
Md. Samiul Islam ◽  
Shakil Ahmed Polash ◽  
Razia Sultana
Keyword(s):  
Volatile Organic Compounds ◽  
Growth Inhibition ◽  
Botrytis Cinerea ◽  
Organic Compounds ◽  
Sclerotinia Sclerotiorum ◽  
Mycelial Growth ◽  
Fungal Growth ◽  
Trichoderma Asperellum ◽  
Volatile Organic ◽  
Fungal Growth Inhibition

Abstract The species of Trichoderma are one of the most frequently used natural biocontrol agents to mitigate plant diseases and improve crop yields. In this study, sixteen Trichoderma spp. were isolated from soil of different regions of China. However, we identified Trichoderma. asperellum HbGT6-07 by initial fungal growth inhibition assay and molecular approach and also evaluated the antimicrobial effects. Tested 10% concentrated culture filtrate of T. asperellum HbGT6-07 inhibited 93 % of colony radial growth in Botrytis cinerea (B05.10) as well as 91 % of Sclerotinia sclerotiorum (A367). VOCs emitted from HbGT6-07 have antimicrobial properties against Botrytis cinerea (B05.10) and Sclerotinia sclerotiorum (A367). In in-vitro DwD method, The T. asperellum HbGT6-07 volatile organic compounds (VOCs) effectively reduced colonial diameter, mycelial growth rate and sclerotia production by two virulent fungal pathogens. The GC-MS analysis identified thirty-two VOCs derived from HbGT6-07 isolates. Moreover, the hyphal fragments of the T. asperellum HbGT6-07 demonstrated successful mycelia growth suppression of two virulent fungal agents by competing toward the invasion on oilseed rape leaves. The above findings indicated that T. asperellum HbGT6-07 could attain competitive progress via volatile antifungal compound production and comprehensive mycelial growth. This study provided an outlook of using T. asperellum HbGT6-07 to control virulent pathogens of B. cinerea and S. sclerotiorum.

scholarly journals Iron-Chelating Compounds Produced by Soil Pseudomonads: Correlation with Fungal Growth Inhibition

1983 ◽  
Vol 46 (1) ◽  
pp. 128-132 ◽  
Author(s):  
Peter A. Vandenbergh ◽  
Carlos F. Gonzalez ◽  
Ann M. Wright ◽  
Blair S. Kunka
Keyword(s):  
Growth Inhibition ◽  
Fungal Growth ◽  
Fungal Growth Inhibition ◽  
Chelating Compounds

An inhibitor of aflatoxin biosynthesis in developing cottonseed

1988 ◽  
Vol 66 (5) ◽  
pp. 998-1002 ◽  
Author(s):  
Susan P. McCormick ◽  
Deepak Bhatnagar ◽  
Wilton R. Goynes ◽  
Louise S. Lee
Keyword(s):  
Growth Inhibition ◽  
Molecular Mass ◽  
Aspergillus Flavus ◽  
Anion Exchanger ◽  
Inhibitory Activity ◽  
Fungal Growth ◽  
Aflatoxin Biosynthesis ◽  
Seed Moisture ◽  
Aflatoxin Accumulation ◽  
Fungal Growth Inhibition

A factor present in the coats of young developing cottonseed (20–25 days old) but absent from older developing seeds (35–40 days old) significantly inhibited (> 85%) aflatoxin formation by Aspergillus flavus without affecting fungal growth. Inhibition was independent of levels of seed moisture, phenolics, or tannins. The inhibitory factor was nondialyzable (molecular mass > 8 kDa); the inhibition of aflatoxin accumulation was dependent on its concentration. The inhibitor was probably an anionic protein since it bound to an anion exchanger and was eluted at 0.15 M salt. The inhibitor did not exhibit a peroxidase-like activity, even though it was observed that the factor was stable at temperatures below 70 °C and that sugar moieties were associated with the inhibitory property. The inhibitory activity was not similar to that of a serine protease.

scholarly journals Efficacy of botanicals and fungicides against Rhizoctonia solani inciting sheath blight disease on Rice (Oryza sativa L.)

2017 ◽  
Vol 9 (4) ◽  
pp. 1916-1920
Author(s):  
Vipin Kumar ◽  
V.P. Chaudhary ◽  
Dharmendra Kumar ◽  
Ajay Kumar ◽  
Sushma Sagar ◽  
...  
Keyword(s):  
Growth Inhibition ◽  
Mycelial Growth ◽  
Allium Sativum ◽  
Oryza Sativa L ◽  
Fungal Growth ◽  
Sheath Blight ◽  
Ocimum Sanctum ◽  
Sheath Blight Disease ◽  
Fungal Growth Inhibition

Among the fungal diseases, sheath blight, caused by multinucleate Rhizoctoniasolani Kuhn (teleomorph: Thanatephorus cucumeris Donk), a ubiquitous pathogen, is an important fungal disease of rice ranking only after blast and often rivalling it. The potential losses due to sheath blight alone in India has been up to 51.3%. In this study an attempt was made to investigate the antifungal efficacy of botanicals viz., neem (Azadirachtaindica), tulsi (Ocimum sanctum), garlic (Allium sativum), onion (Allium cepa), ginger (Zingiberofficinale) and various fungicides namely mancozeb, propiconazole, hexaconazole, carbendazim, and copper oxychlorideagainst Rhizoctoniasolani in vitro by poison food technique. R. solani was allowed to grow at 5%, 10% concentrations of botanicals and at 200, 500, 1000ppm of fungicides amended potato dextrose agar (PDA) medium. The effect of botanicals and fungicides on mycelial growth inhibition was recorded after 36, 48 and 72 post hrs inoculation (phi). It was observed that bulb extract of Allium sativum and rhizome extract of Zingier officinal suppressed the mycelial growth (80.19 and 76.32, respectively) @ 10% followed by leaf extract of Azadirachtaindica (72.78 %) after 72 phi. Among the fungicides, the complete fungal growth inhibition was observed in propiconazole and carbendazim fungicides amended medium.

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