Chromatographic profiles of antifungal exo- and endometabolites of Bacillus velezensis

The antifungal activity of the Bacillus bacteria is based on their ability to produce metabolites. Therefore, when selecting a strain that produces an effective biofungicide, it is necessary to assess the metabolism of bacteria. The aim of this work is to isolate exo- and endometabolites of the promising B. velezensis BZR 336g and B. velezensis BZR 517 strains and assess their antifungal activity. Studies were carried out in 2020–2021. The object of the study is a liquid culture of the B. velezensis BZR 336g and B. velezensis BZR 517 strains. Methods of liquid extraction, ascending thin layer chromatography (TLC), bioautography with a test-culture of Fusarium oxysporum var. orthoceras and Alternaria sp. fungi were used to analyze metabolites. The ability of the strains to accumulate a complex of active metabolites showing antifungal effect from fungistatic to fungicidal action was revealed. On the bioautogram of exometabolites, we found two most pronounced zones (Rf 0.18 and 0.29) of Fusarium oxysporum var. orthoceras BZR P1 growth inhibition (fungicide). Zones with Rf 0.58 for B. velezensis BZR 336g and Rf 0.70 for B. velezensis BZR 517 correspond to the test fungus growth retardation (fungistatic). Significant suppression of Alternaria sp. BZR P8 growth was also observed in two zones (Rf 0.18 and 0.29). The use of surfactin, iturin A, fengycin (Sigma-Aldrich®) in the TLC analysis made it possible to detect similar lipopeptides in the composition of metabolite complexes produced by the studied bacteria. It should be noted that the studied strains differed both in their ability to produce metabolites of different structure (can be found when analyzing chromatograms under ultraviolet light) and in their effect on phytopathogenic fungi in vitro. This may indicate possible differences in the mechanism of antagonistic activity of bacteria against phytopathogenic fungi. Thus, B. velezensis BZR 336g and B. velezensis BZR 517 produce a significant set of antifungal metabolites and can be used as strains to produce effective biofungicides.

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Synthesis and Antifungal Activities of Some 2,6-Bis-(Un)Substituted Phenoxymethylpyridines

Zeitschrift für Naturforschung C ◽

10.1515/znc-2010-7-802 ◽

2010 ◽

Vol 65 (7-8) ◽

pp. 433-436

Author(s):

Hui Xu ◽

Huan Qu

Keyword(s):

Antifungal Activity ◽

Fusarium Oxysporum ◽

Fusarium Graminearum ◽

Broad Spectrum ◽

Alternaria Alternata ◽

Phytopathogenic Fungi ◽

Alternaria Brassicae ◽

Antifungal Activities

Several 2,6-bis-(un)substituted phenoxymethylpyridines were synthesized and evaluated in vitro against Fusarium graminearum, Helminthosporium sorokinianum, Alternaria brassicae, Alternaria alternata, and Fusarium oxysporum f. sp. vasinfectum. Among all derivatives, compound 3 a exhibited a broad-spectrum antifungal activity against the five phytopathogenic fungi.

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Cladobotryum mycophilum as Potential Biocontrol Agent

Agronomy ◽

10.3390/agronomy9120891 ◽

2019 ◽

Vol 9 (12) ◽

pp. 891

Author(s):

Mila Santos ◽

Fernando Diánez ◽

Alejandro Moreno-Gavíra ◽

Brenda Sánchez-Montesinos ◽

Francisco J. Gea

Keyword(s):

Biological Control ◽

Fusarium Oxysporum ◽

Biocontrol Agent ◽

Biological Control Agent ◽

Control Agent ◽

Phytopathogenic Fungi ◽

Antagonistic Activity ◽

Dual Culture ◽

Potential Biocontrol Agent

A study was conducted to explore the efficacy of potential biocontrol agent Cladobotryum mycophilum against different phytopathogenic fungi. The growth rates of 24 isolates of C. mycophilum were determined, and their antagonistic activity was analysed in vitro and in vivo against Botrytis cinerea, Fusarium oxysporum f. sp. radicis-lycopersici, Fusarium oxysporum f.sp. cucumerinum, Fusarium solani, Phytophthora parasitica, Phytophthora capsici, Pythium aphanidermatum and Mycosphaerella melonis. Most isolates grow rapidly, reaching the opposite end of the Petri dish within 72–96 h. Under dual-culture assays, C. mycophilum showed antagonistic activity in vitro against all phytopathogenic fungi tested, with mycelial growth inhibition ranging from 30 to 90% against all the different phytopathogens tested. Similarly, of all the selected isolates, CL60A, CL17A and CL18A significantly (p < 0.05) reduced the disease incidence and severity in the plant assays compared to the controls for the different pathosystems studied. Based on these results, we conclude that C. mycophilum can be considered as a potential biological control agent in agriculture. This is the first study of Cladobotryum mycophilum as a biological control agent for different diseases caused by highly relevant phytopathogens in horticulture.

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ASSESSMENT OF SOME ABIOTIC FACTORS ON MICROBIAL BIOPRODUCTS USEFUL IN BIOCONTROL OF PHYTOPATHOGENS

JOURNAL OF ADVANCES IN AGRICULTURE ◽

10.24297/jaa.v5i3.5052 ◽

2016 ◽

Vol 5 (3) ◽

pp. 799-803

Author(s):

Sergiu Fendrihan ◽

Sorina Dinu ◽

Oana Alina Sicuia ◽

Florica Constantinescu

Keyword(s):

Abiotic Factors ◽

Fungal Growth ◽

Phytopathogenic Fungi ◽

Antagonistic Activity ◽

Antagonistic Effect ◽

Limiting Factors ◽

Multiplication Rate ◽

Antifungal Metabolites ◽

Ph Conditions

The environmental factors may influence the growth of microorganisms, by favoring their growth or slowing their multiplication rate and the synthesis of different metabolites. Parameters such as temperature, aeration, nutrients, pH or tolerance to NaCl can become limiting factors for microorganisms survival. Bacillus subtilis and related species can grow in variable pH conditions, maintaining the cytoplasmically pH in a relatively close range, stable to the synthesis of proteins and nucleic acids.The aim of this work was to assess the influence of some abiotic factors on the biocontrol activity of microbial bioproducts, based on beneficial strains from Bacillus sp.. The bioproducts were tested in vitro against soil borne fungi at different temperatures and pH conditions. The results showed that the antagonistic activity of the biopreparates, tested at 27Â°C and 25Â°C, against phytopathogenic fungi released antifungal metabolites which inhibited the fungal growth. Also, when different pH values were analyzed, the results reflected that at pH 5.5 and pH 8.5 the bioproducts maintained the same antagonistic effect as in the control variant (pH 7.0).

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Fungal Metabolites with Antagonistic Activity against Fungi of Lithic Substrata

Biomolecules ◽

10.3390/biom11020295 ◽

2021 ◽

Vol 11 (2) ◽

pp. 295

Author(s):

Marco Masi ◽

Mariagioia Petraretti ◽

Antonino De Natale ◽

Antonino Pollio ◽

Antonio Evidente

Keyword(s):

Antifungal Activity ◽

Fusarium Oxysporum ◽

Animal Health ◽

Antagonistic Activity ◽

Building Stones ◽

Fungal Metabolites ◽

Synthetic Chemicals ◽

Culture Heritage ◽

Reduced Toxicity

Fungi are among the biotic agents that can cause deterioration of building stones and cultural heritage. The most common methods used to control fungal spread and growth are based on chemical pesticides. However, the massive use of these synthetic chemicals produces heavy environmental pollution and risk to human and animal health. Furthermore, their use is time dependent and relies on the repetition of treatments, which increases the possibility of altering building stones and culture heritage through environmental contamination. One alternative is the use of natural products with high antifungal activity, which can result in reduced toxicity and deterioration of archeological remains. Recently, three fungal strains, namely Aspergillus niger, Alternaria alternata and Fusarium oxysporum, were isolated as damaging agents from the external tuff wall of the Roman remains “Villa of Poppea” in Oplontis, Naples, Italy. In this manuscript, three selected fungal metabolites, namely cyclopaldic acid, cavoxin and epi-epoformin, produced by fungi pathogenic for forest plants, were evaluated as potential antifungal compounds against the above fungi. Cavoxin and epi-epoformin showed antifungal activity against Asperigillus niger and Fusarium oxysporum, while cyclopaldic acid showed no activity when tested on the three fungi. The same antifungal activity was observed in vitro experiments on infected stones of the Neapolitan yellow tuff (NYT), a volcanic lithotype widely diffused in the archeological sites of Campania, Italy. This study represents a first step in the use of these two fungal metabolites to allow better preservation of artworks and to guarantee the conditions suitable for their conservation.

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Antifungal activity in vitro of Flourensia spp. extracts on Alternaria sp., Rhizoctonia solani, and Fusarium oxysporum

Industrial Crops and Products ◽

10.1016/j.indcrop.2006.08.007 ◽

2007 ◽

Vol 25 (2) ◽

pp. 111-116 ◽

Cited By ~ 26

Author(s):

D. Jasso de Rodríguez ◽

D. Hernández-Castillo ◽

J.L. Angulo-Sánchez ◽

R. Rodríguez-García ◽

J.A. Villarreal Quintanilla ◽

...

Keyword(s):

Antifungal Activity ◽

Rhizoctonia Solani ◽

Fusarium Oxysporum ◽

Alternaria Sp

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In vitro CONFRONTATION OF Trichoderma spp. ISOLATES WITH PHYTOPATHOGENIC AND NON-PHYTOPATHOGENIC FUNGI

JOURNAL OF NEOTROPICAL AGRICULTURE ◽

10.32404/rean.v3i2.810 ◽

2016 ◽

Vol 3 (2) ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Milton Luiz da Paz Lima ◽

Maria Cristina Araújo Vaz ◽

Aline Suelen da Silva ◽

Karoliny De Almeida Souza ◽

Gabriel Isaias Lee Tuñon

Keyword(s):

Filamentous Fungi ◽

Pathogenic Fungi ◽

Phytopathogenic Fungi ◽

Antagonistic Activity ◽

Trichoderma Spp ◽

Opposite Position ◽

Trichoderma Isolate ◽

Alternaria Sp ◽

Area Percentage

The aim of this study was the confrontation of Trichoderma spp. with pathogenic and non-pathogenic fungi. The Trichoderma spp. and filamentous fungi (Fusarium solani, Alternaria sp., Colletotrichum gloeosporioides, and Aspergillus niger) were transferred to potato-dextrose-agar (PDA). The confrontation was performed using Petri dishes inoculated with mycelial disks in opposite position (9 mm) of Trichoderma spp. and filamentous fungi. After inoculation the plates remained under 25 ° C regime to 12 hours light for a period of seven days. After this period was evaluated qualitatively according to the scale of Bell et al. (1982), which consists of the suitability scores for the area percentage of the culture medium under expression of antagonism. The isolate of C. gloeosporioides (jatropha) was isolated which had statistically slightly inhibited growth by Trichoderma spp., Unlike the isolated Alternaria sp. (parsley) was isolated micelial fungi suffered the most antagonism. Statistically the Trichoderma isolate derived from pineapple promoted the highest antagonistic activity against isolates of pathogenic fungi tested, being a candidate for use in biocontrol.

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Microencapsulation of Citral and its Antifungal Activity into Pectin Films

Biointerface Research in Applied Chemistry ◽

10.33263/briac126.74887502 ◽

2021 ◽

Vol 12 (6) ◽

pp. 7488-7502

Keyword(s):

Antifungal Activity ◽

Large Scale ◽

Thermal Protection ◽

Thermal Analyses ◽

Phytopathogenic Fungi ◽

Antagonistic Activity ◽

Drying Process ◽

Practical Applications ◽

Postharvest Management

Citral is an essential oil with great antimicrobial activity, but its use in the food industry is limited due to its easy decomposition in room conditions. Therefore, this study aimed to microencapsulate citral by the spray drying process and incorporate the powder into pectin films to assess their antifungal activity. For this, solutions of maltodextrin (MD), Arabic gum (AG) sodium alginate (SA) at different concentrations were used to emulsify citral. The emulsion with 10:10:0.1 MD:AG:SA was selected to spray the drying process due to its small droplet size, monomodal size distribution, and low D[3,2], D[4,3], and span index. The dried powder had high solubility (83.4%), and low wettability time (27 s), moisture content (4.05%), and bulk density (0.72 g/cm3), allowing to infer powder stability and showing appropriate handling qualities on a large scale. Thermal analyses reveal that microparticles and pectin films provide thermal protection to citral from 37 to 175 °C. Concerning the antagonistic activity, pectin films added with citral microencapsulated had antifungal activity ranging from 42-68% against Penicillium italicum, Colletotrichum gloeosporioides, and Aspergillus niger under in vitro conditions. Therefore, these films serve as a basis for developing new edible coatings with practical applications in the postharvest management of phytopathogenic fungi.

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Antifungal activity of essential oils on mycelial growth of Fusarium oxysporum and Bortytis cinerea

Emirates Journal of Food and Agriculture ◽

10.9755/ejfa.2019.v31.i7.1972 ◽

2019 ◽

pp. 544 ◽

Cited By ~ 3

Author(s):

Marina Palfi ◽

Paško Konjevoda ◽

Karolina Vrandečić

Keyword(s):

Antifungal Activity ◽

Essential Oil ◽

Essential Oils ◽

Fusarium Oxysporum ◽

Mycelial Growth ◽

In Vitro Study ◽

Phytopathogenic Fungi ◽

Phytopathogenic Fungus ◽

Antifungal Effect

In vitro study of the effect of different volumes of twelve essential oils on the mycelial growth of economically significant phytopathogenic fungi (Fusarium oxysporum and Botrytis cinerea) and it was compared to the effect of a fungicide. The antifungal activity of essential oils is decreased with the duration of incubation and it differs depending on the type of phytopathogenic fungus and the applied volume. The most effective antifungal effect on both tested fungi was in the essential oil of thyme, with lowest values of IC50 while the weakest effect was in essential oils of eucalyptus and lemon, with the highest values of IC50. Certain essential oils, when applied in certain volumes, had the same or even better effect on the inhibition of the growth of mycelium when compared to the tested fungicides.

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Biocontrol potential of Streptomyces sp. CACIS-1.5CA against phytopathogenic fungi causing postharvest fruit diseases

Egyptian Journal of Biological Pest Control ◽

10.1186/s41938-020-00319-9 ◽

2020 ◽

Vol 30 (1) ◽

Author(s):

Zahaed Evangelista-Martínez ◽

Erika Anahí Contreras-Leal ◽

Luis Fernando Corona-Pedraza ◽

Élida Gastélum-Martínez

Keyword(s):

Pathogenic Fungi ◽

Phytopathogenic Fungi ◽

Antagonistic Activity ◽

Fruit Rot ◽

Main Body ◽

Type I ◽

Tropical Fruit ◽

Habanero Pepper ◽

Antagonistic Microorganisms

Abstract Background Fungi are one of the microorganisms that cause most damage to fruits worldwide, affecting their quality and consumption. Chemical controls with pesticides are used to diminish postharvest losses of fruits. However, biological control with microorganisms or natural compounds is an increasing alternative to protect fruits and vegetables. In this study, the antifungal effect of Streptomyces sp. CACIS-1.5CA on phytopathogenic fungi that cause postharvest tropical fruit rot was investigated. Main body Antagonistic activity was evaluated in vitro by the dual confrontation over fungal isolates obtained from grape, mango, tomato, habanero pepper, papaya, sweet orange, and banana. The results showed that antagonistic activity of the isolate CACIS-1.5CA was similar to the commercial strain Streptomyces lydicus WYEC 108 against the pathogenic fungi Colletotrichum sp., Alternaria sp., Aspergillus sp., Botrytis sp., Rhizoctonia sp., and Rhizopus sp. with percentages ranging from 30 to 63%. The bioactive extract obtained from CACIS-1.5 showed a strong inhibition of fungal spore germination, with percentages ranging from 92 to 100%. Morphological effects as irregular membrane border, deformation, shrinkage, and collapsed conidia were observed on the conidia. Molecularly, the biosynthetic clusters of genes for the polyketide synthase (PKS) type I, PKS type II, and NRPS were detected in the genome of Streptomyces sp. CACIS-1.5CA. Conclusions This study presented a novel Streptomyces strain as a natural alternative to the use of synthetic fungicides or other commercial products having antagonistic microorganisms that were used in the postharvest control of phytopathogenic fungi affecting fruits.

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