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Relevance. The use of chemical fungicides in protecting plants from pathogens is the most common way, despite the proven danger of pesticides. The use of biofungicides based on essential oils of medicinal plants, which also have phytoncidal properties, can be a suitable alternative to chemical preparations. In the years favorable for the development of alternariosis or cladosporiosis, spots appear on the plants, leading to necrosis and significant loss of seed productivity. Therefore, the search for new effective and safe means of combating fungal phytopathogens becomes relevant.Methods. Alternaria alternata (2018-1.1) and Cladosporium cladosporioides (2019-11.4) strains were isolated from leaves with signs of alternariosis and cladosporiosis, on which the essential oils Abies alba, Artemisia vulgaris, Caryophyllus aromaticus, Coriandrum sativum, Lavandula officinalis, Ocimum basilicum, Pimpinella anisum, Rosmarinus officinalis, Salvia sclarea, Thymus vulgaris. The antifungal activity of essential oils was evaluated by comparing the diameter of the experimental (with the addition of essential oil to the Petri dish) and control colonies using the author’s scale.Results. All studied essential oils had antifungal properties, but species-specificity was observed. Essential oils of basil, coriander and thyme showed a fungicidal effect on C. cladosporioides and A. alternata. Lavender oil proved to be a fungicide for A. alternata and a strong fungistatic for C. cladosporioides. To create biological products for plant protection against alternariosis, sage essential oil (moderate fungistatic effect) may also be of interest, and cladosporiosis - anise and rosemary oils.

Enniatins are mycotoxins produced by Fusarium species contaminating cereals and various agricultural commodities. The co-occurrence of these mycotoxins in large quantities with other mycotoxins such as trichothecenes and the possible synergies in toxicity could lead to serious food safety problems. Using the agar dilution method, Ammoides pusilla was selected among eight Tunisian plants for the antifungal potential of its essential oil (EO) on Fusarium avenaceum mycelial growth and its production of enniatins. Two EO batches were produced and analyzed by GC/MS-MS. Their activities were measured using both contact assays and fumigant tests (estimated IC50 were 0.1 µL·mL−1 and 7.6 µL·L−1, respectively). The A. pusilla EOs and their volatiles inhibited the germination of spores and the mycelial growth, showing a fungistatic but not fungicidal activity. The accumulation of enniatins was also significantly reduced (estimated IC50 were 0.05 µL·mL−1 for the contact assays and 4.2 µL·L−1 for the fumigation assays). The most active batch of EO was richer in thymol, the main volatile compound found. Thymol used as fumigant showed a potent fungistatic activity but not a significant antimycotoxigenic activity. Overall, our data demonstrated the bioactivity of A. pusilla EO and its high potential to control F. avenaceum and its enniatins production in agricultural commodities.

The aim of the study was to determine the relationship between the chemical composition of eight commercial essential oils (EsO) (garlic, grapefruit, lemon grass, tea tree, thyme, verbena, cajeput, and Litsea cubeba) and their fungistatic activity in relation to four species of Fusarium: F. avenaceum, F. culmorum, F. graminearum, and F. oxysporum. The species identification of Fusarium isolates was confirmed by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometer. The determination of qualitative and quantitative chemical composition of the EsO was carried out using the gas chromatography&ndash, mass spectrometry (GC&ndash, MS) method. The fungistatic activity of EsO was assessed by using the method of poisoned substrates. The data were compiled in the STATISTICA 13.0 program. The chemical composition of the tested oils varied, the dominant fraction, except for grapefruit and garlic oils, were monoterpenoids. The greatest similarity to the action of the synthetic pesticide Funaben T was found in four oils, i.e., thyme, lemongrass, verbena, and Litsea cubeba. The studies showed that F. oxysporum and F. avenaceum were characterized by a higher resistance to low oil concentrations, and F. culmorum and F. graminearum by sensitivity. The fungicidal activity of two EsO-dominant monoterpenoids-thymol and citral&mdash, has been confirmed.

Introduction: Antifungal resistant is one of the causes of high mortality rates during invasive candidiasis. Since development of new antifungal agents is limited, researchers have focused on natural products including essential oils (EOs) with antifungal properties. In immunocompromised patients fungicidal activity is of benefit. This study was designed to evaluate chemical composition and fungicidal/fungistatic activities of five Iranian EOs and against fluconazole resistant Candida species. Methods: To determine chemical composition of EOs gas chromatography-mass spectroscopy (GC/MS) was employed. Fluconazole resistant Candida species were chosen and minimum inhibitory concentration (MIC) values of studied EOs were determined by broth microdilution method. Minimum fungicidal concentration (MFC) was determined as the lowest concentration with no fungal growth on solid media. Fungicidal activity was calculated by MFC/MIC ratio. Results: The results showed that C. albicans and C. tropialis isolates were susceptible to itraconazole (ITC) and voriconazole (VRC) while one species of C. glabrata and C. krusei each was resistant to itraconzaole; and itraconazole resistant C. glabrata isolate was resistance to voriconzaole as well. Among tested EOs, the ones from Cinnamomum cayennense, Origanum majorana var. majoranoides and Andropogon citratus had the highest anti-Candida activity. Artemisia aromatica A. Nelson had the highest MIC value against Candida isolates. All EOs in this study had fungicidal activity. Conclusion: In general, the tested natural compounds are suitable to be used as anti-Candida. However more studies are needed on each chemical compound to evaluate its antifungal activity alone or in combination with other agents.

Objective: To investigate the fungistatic activity and synergistic effects of natural products and their constituents, including traditional oriental medicines (TOMs). Methods: Fungistatic activities of TOMs prepared by hot-water (115 °C) or ethanol (70%; 40 °C) extraction were determined by their minimum inhibitory concentration. To assess possible synergistic effects, minimum inhibitory concentrations of various combinations were evaluated. Results: By evaluating antifungal susceptibility of Trichophyton rubrum, which is a major causative fungus for several types of dermatophytosis, we confirmed that ethanol extracts were more active than hot-water extracts in 25 of the 36 TOMs, suggesting that the constituents with high hydrophobicity tend to contribute significantly to fungistatic activity. We selected four TOMs with high fungistatic activity, including Aucklandiae radix, Gentianae macrophyllae radix, Scutellariae radix, and Galla rhois, and their synergistic effects were investigated through the combination studies between TOMs or TOM-conventional drug terbinafine. In combinations between four TOMs, partial synergistic effects were observed in Aucklandiae radix–Galla rhois and Gentianae macrophyllae radix–Galla rhois combinations, as supported by the lowest fractional inhibitory concentration index value of 0.66 for both combinations. Furthermore, Galla rhois showed the strongest synergistic effect on growth inhibition of Trichophyton rubrum with a fractional inhibitory concentration index value of 0.50 in combination with terbinafine. Conclusions: Our findings indicate that the combination of TOMs and TOM-terbinafine may be effective on treatment for chronic and recurrent dermatophytosis by improving fungistatic activity and led to decrease systemic toxicity in clinical practice.

The reactions of 3-isoselenocyanato-2,2,5,5-tetramethylpyrrolidine-1-oxyl, 3-isoselenocyanatomethyl-2,2,5,5-tetramethyl-3-pyrrolidine-1-oxyl, and 4-isoselenocyanato-2,2,6,6-tetramethylpiperidine-1-oxyl with selected amines and alcohols give the corresponding novel nitroxyl selenoureas and selenocarbamates, all bearing a nitroxyl moiety. Synthesized selenoureas and selenocarbamates show significant activity against pathogenic fungi and bacteria. In contrast to piperidine nitroxides, pyrrolidine, five-membered nitroxyl selenoureas and selenocarbamates show excellent antifungal and antibacterial activity against pathogenic fungi and bacteria, respectively.

Purpose Fungal infections are a major complication in hematologic and neoplastic patients causing severe morbidity and mortality. Aspergillus fumigatus and Candida albicans are among the most invasive opportunistic pathogens in immunocompromised patients, and classic antifungal drugs are frequently unsuccessful in these patients. Recent reports hypothesize that the antifungal efficacy of all-trans retinoic acid (ATRA) is mainly related to its strong capacity to stimulate monocyte-mediated immunity, but no consideration was given to its potential direct fungistatic activity. Moreover, ATRA offers the opportunity for systemic therapy. Methods and results We investigated the efficacy of ATRA at different concentrations for its antifungal activity against opportunistic A. fumigatus and C. albicans obtained from clinical samples according to standard protocols. A fungistatic activity of ATRA on A. fumigatus and C. albicans at 0.5–1 mM concentration was documented up to 7 days. Conclusion This is the first evidence of a direct and strong fungistatic activity of ATRA against A. fumigatus and C. albicans. The potential adjuvant therapeutic application of ATRA might be useful in the treatment and/or prevention of systemic mycoses in immunocompromised patients. The discovery of a direct fungistatic activity, in association with its reported immunomodulatory properties, makes ATRA an excellent candidate for new combined antifungal strategies for systemic mycoses in immunocompromised and cancer patients., Video abstract

The aim of the study was to detect the activity and characterize potentially fungistatic chitinases synthesized by rhizosphere bacteria identified as Paenibacillus sp. M4. Maximum chitinolytic activity was achieved on the fifth day of culturing bacteria in a growth medium with 1% colloidal chitin. Analysis of a zymogram uncovered the presence of four activity bands in the crude bacterial extract. The used three-stage protein purification procedure resulted in a single band of chitinase activity on the zymogram. The purified enzyme exhibited maximum activity at pH 6.5 and temperature 45oC, and thermal stability at 40oC for 4 h. In terms of substrate specificity, it is an exochitinase (chitobiose). The amino acid sequence obtained after mass spectrometry showed similarity to chitinase A1 synthesized by Bacillus circulans. The M4 isolate demonstrated the highest growth inhibiting activity against plant pathogens belonging to the genera Fusarium, Rhizoctonia and Alternaria. Fungistatic activity, although to a somewhat lesser degree, was also demonstrated by purified chitinase. The obtained results confirm the participation of the studied exochitinase in antagonism towards pathogenic molds. However, the lower fungistatic effectiveness of the chitinases points to the synergistic action of different metabolites in biocontrol by these bacteria.

Herein, we describe a modified form of the antimicrobial hairpin-like peptide EcAMP1, isolated from barnyard grass (E. crusgalli) seeds, which is structurally characterized by a combination of high-pressure liquid chromatography, mass spectrometry, and automated Edman sequencing. This derivate has a single amino acid substitution (Pro19Hyp) in the second &alpha, helical region of the molecule, which is critical for the formation of the hydrophobic core and the secondary structure elements. Comparing the antifungal activity of these two peptides, we found that the modified EcAMP1-Hyp had a significantly weaker activity towards the most-sensitive plant pathogenic fungus Fusarium solani. Molecular dynamics simulations and in vitro binding to the commercial polysaccharides allowed us to conclude that the Pro-19 residue is important for binding to carbohydrates located in the spore cell wall and it chiefly exhibits a fungistatic action representing the hyphal growth inhibition. These data are novel and significant for understanding a role of &alpha, hairpinins in plant immunity.

This study aimed to evaluate the fungitoxic (antifungal) effect of seven essential oils on Plasmopara viticola, the causal agent of grapevine downy mildew. The cinnamon, eucalyptus globulus, marjoram, melaleuca, peppermint, oregano and white thyme essential oils were compared with the mancozeb + metalaxyl-M fungicide. Three experiments were conducted to evaluate the effect of essential oils on spore germination. The first experiment evaluated the effect of direct contact of essential oils on the pathogen; the second evaluated the effect of volatile compounds on the pathogen and the third assessed the behavior of essential oils, when applied to vine leaves in field conditions, on the pathogen. All essential oils inhibited the spores’ germination, but in varying degrees, in addition, presenting fungistatic activity. All the essential oils showed chemical instability when the incubation time or the interval between products application where increased, all oils decrease antifungal activity percentage. Noteworthy, the cinnamon and the eucalyptus globulus essential oils were the most fungitoxic (antifungal) on P. viticola. RESUMO O estudo teve como objetivo avaliar o efeito antifúngico de sete óleos essenciais sobre a germinação de esporos de Plasmopara viticola, agente causal do míldio da videira. Os óleos essenciais de canela, eucalipto globulus, manjerona, melaleuca, peppermint, orégano e tomilho branco foram comparados com o fungicida mancozebe + metalaxil-M. Foram realizados três experimentos avaliando o efeito dos óleos essenciais na germinação de esporos. O primeiro experimento avaliou o efeito do contato direto dos óleos essenciais sobre o patógeno; o segundo avaliou o efeito dos compostos voláteis sobre o patógeno e o terceiro avaliou o comportamento dos óleos essenciais, quando aplicados em folhas de videira em condições de campo, sobre o patógeno. Todos os óleos essenciais inibiram a germinação dos esporos de P. viticola, mas em graus variáveis, além de apresentarem atividade fungistática. Todos os óleos essenciais possuem instabilidade química, visto que, à medida que se aumenta o tempo de incubação ou o intervalo entre a aplicação dos produtos, a percentagem de atividade antifúngica de todos os óleos diminui. Nos menores períodos de incubação, mas em altas concentrações, os óleos essenciais são tão eficientes quanto o fungicida. Destacam-se os óleos essenciais de canela e eucalipto globulus como os mais antifúngicos sobre P. viticola.

The aim of the work was to determine the usefulness of dried leaves of savoy cabbage, red cabbage, horse radish and fringed cabbage in protection of cucumber against damping-off caused by fungi Rhizoctonia solani and Fusarium culmorum. In the laboratory experiments, pathogens were grown on PDA containing dried leaves (3g·100 cm-3) and in atmosphere containing volatile substances evolved from plant material. The addition of radish horse leaves into PDA caused total inhibition of R. solani development. Remaining plants were also characterized by high fungistatic activity (% of growth inhibition about 85%). F. culmorum was less sensitive. The horse radish leaves showed the strongest activity (65 %), weakest in combination with fringed cabbage leaves (38,9%). The similar regularity in the case of fumigation activity was observed. The effectiveness of dried leaves in protection of cucumber against damping-off was confirmed in greenhouse experiment. The amendment of soil inoculated with R. solani in dose 2 g per 500 cm3 of soil significantly increased the number of cucumber sprouts compared to the control. In the experiment with F. culmorum only in combination with horse radish and red cabbage leaves significant action was observed.

Resumen Los extractos etanólicos del propóleos poseen actividad antifúngica en diferentes especies de levaduras, propiedad de importancia por ser una opción terapéutica económica y poco toxica respecto a los antimicóticos tradicionales, de particular utilidad sobre especies del complejo Candida albicans, patógeno oportunista. A pesar de que la composición química general del propóleos es similar en las distintas regiones del mundo, su actividad antifúngica no parece serlo. El objetivo fue determinar la actividad fungistática y fungicida de propóleos venezolano y de 3 regiones del mundo. Para ello cepas del Complejo C. albicans, C. guillermondi, C. krusei y C. tropicalis se enfrentaron a distintas concentraciones de extractos etanólicos de propóleos. Los propóleos de mayor actividad biológica fueron los de Alemania e Italia (10,2 mg/mL), seguidos por el de Venezuela (15,6 mg/mL) y España (18,8 mg/mL). La CMI en las especies más sensibles a los propóleos fueron C. krusei y C. guilliermondii (8,6 mg/mL como promedio de los 4 propóleos). Los extractos etanólicos de propóleos italiano y alemán son fungicidas en todas las cepas estudiadas en diluciones de 1/32 (concentración final de 3,12 mg/dL).Se concluye que los extractos etanólicos de propóleos tienen efectos fungistáticos y fungicidas sobre las especies del Complejo C. albicans, C. krusei, C. guilliermondii y C. tropicalis; que C. tropicalis es la especie más resistente a la acción biológica del propóleos y C. krusei y C. guilliermondii las más sensibles; que los propóleos de Alemania e Italia son los más efectivos contra las especies de Candida aisladas de pacientes venezolanas. Abstract Ethanol extracts of propolis have antifungal activity in different species of yeast, owned by importance as a therapeutic economic option and low toxicity compared to traditional antifungal, particularly useful on species of Candida albicans, opportunistic pathogen. Although the overall chemical composition of propolis is similar in different regions of the world, their antifungal activity does not seem to be. The objective was to determine the fungistatic and fungicidal activity of Venezuelan propolis and 4 parts of the world. To do strains of C. albicans, C. guillermondi, C. krusei and C. tropicalis faced different concentrations of ethanol extracts of propolis. Propolis increased biological activity were from Germany and Italy (10.2 mg / mL), followed by that of Venezuela (15.6 mg / mL) and in Spain (18.8 mg / mL). The CMI in the most sensitive species to propolis were C. krusei and C. guilliermondii (8.6 mg / mL as an average of 4 propolis). Ethanol extracts of propolis Italian and German origin are fungicides in all strains tested at dilutions of 1/32 (final concentration of 3.12 mg/dL). It is concluded that ethanol extracts of propolis have significant fungistatic and fungicidal effects on species C. albicans, C. krusei, C.guilliermondii and C. tropicalis; C. tropicalis is the most resistant to biological action of propolis and C. krusei and C. guilliermondii the most sensitive species; propolis that Germany and Italy are the most effective against species of Candida isolated from Venezuelan patients.

International audience; A new process using aminoalkylalkoxysilanes (AAAS) was developed recently for paper and book mass deacidification. This process is entirely novel in that, besides deacidifying, it also improves the mechanical properties of paper. In the present article, the properties of inhibition of fungal growth of the treated papers are investigated. It was found that the AAAS tested acted as surface-active antifungal agents when introduced in the paper, significantly reducing the growth of Aspergillus niger and Paecilomyces variotii, two fungal species commonly found in storage areas of libraries and archives. The AAAS which seemed the most efficient in preventing the fungal development was 3-aminopropylmethyldi-methoxysilane (AMDES), functionalised with a primary amine. The effect was significant in the different papers tested which demonstrated the protection against the proliferation of filamentous fungi in vitro for papers treated with AMDES. The higher concentration of AMDES inside the paper proved to be the most effective. The highest efficiency was reached for AAAS uptakes around 6%. At this concentration the sporulation of the two strains was inhibited and the development of A. niger mycelia was highly reduced.