Fluoro-substituted pyrazoles have a wide range of biological activities, such as antibacterial, antiviral, and antifungal activities. The aim of this study was to evaluate the antifungal activities ...of fluorinated 4,5-dihydro-1
-pyrazole derivatives on four phytopathogenic fungi:
,
,
f. sp
, and
. Moreover, they were tested on two soil beneficial bacteria-
and
-as well as two entomopathogenic nematodes (EPNs)-
and
. The molecular docking was performed on the three enzymes responsible for fungal growth, the three plant cell wall-degrading enzymes, and acetylcholinesterase (AChE). The most active compounds against fungi
were 2-chlorophenyl derivative (
) (43.07% of inhibition) and 2,5-dimethoxyphenyl derivative (
) (42.23% of inhibition), as well as
against
(46.75% of inhibition). Compounds were shown to be safe for beneficial soil bacteria and nematodes, except for compound
on EPN
(18.75% mortality), which also showed the strongest inhibition against AChE (79.50% of inhibition). The molecular docking study revealed that antifungal activity is possible through the inhibition of proteinase K, and nematicidal activity is possible through the inhibition of AChE. The fluorinated pyrazole aldehydes are promising components of future plant protection products that could be environmentally and toxicologically acceptable.
Coumarin derivatives have been reported as strong antifungal agents against various phytopathogenic fungi. In this study, inhibitory effects of nine coumarinyl Schiff bases were evaluated against the ...plant pathogenic fungi (
f. sp.
,
,
and
). The compounds were demonstrated to be efficient antifungal agents against
. The results of molecular docking on the six enzymes related to the antifungal activity suggested that the tested compounds act against plant pathogenic fungi, inhibiting plant cell-wall-degrading enzymes such as endoglucanase I and pectinase. Neither compound exhibited inhibitory effects against two beneficial bacteria (
and
) and two entomopathogenic nematodes. However, compound
was lethal (46.25%) for nematode
and showed an inhibitory effect against acetylcholinesterase (AChE) (31.45%), confirming the relationship between these two activities. Calculated toxicity and the pesticide-likeness study showed that compound
was the least lipophilic compound with the highest aquatic toxicity. A molecular docking study showed that compounds
and
bind directly to the active site of AChE. Coumarinyl Schiff bases are promising active components of plant protection products, safe for the environment, human health, and nontarget organisms.
This article presents fungicidal properties of 9 synthesized nicotinamide-bromides with different alkyl side chain lengths toward
Fusarium graminearum
,
Sclerotinia sclerotiorum
, and
Botrytis ...cinerea
which were examined. The fungicidal properties were determined by the measurement of the radial growth of fungi, followed by the calculation of the antifungal index. The obtained results were correlated with the descriptors from DFT calculations to determine structural features that affect the fungicidal properties of nicotinamides. Based on the experimental and theoretical results, it was confirmed that
F. graminearum
is most resistant to the change of lipophilicity of compounds, while
S. sclerotiorum
is most sensitive. For all investigated compounds, the growth rate decreased with the increase of carbon atoms in the side chain until tetradecylnicotinamidium bromide, C14NicBr, while the further prolongation of the alkyl side chain increased the growth rate of fungus. This behavior was explained by the distinguished hydrophobic and hydrophilic surfaces in C14NicBr due to interactions between keto oxygen and bromide anion absent in the case of nicotinamides with a longer chain.
The aim was to study the inhibitory effects of coumarin derivatives on the plant pathogenic fungi, as well as beneficial bacteria and nematodes. The antifungal assay was performed on four cultures of ...phytopathogenic fungi by measuring the radial growth of the fungal colonies. Antibacterial activity was determined by the broth microdilution method performed on two beneficial soil organisms. Nematicidal activity was tested on two entomopathogenic nematodes. The quantitative structure-activity relationship (QSAR) model was generated by genetic algorithm, and toxicity was estimated by T.E.S.T. software. The mode of inhibition of enzymes related to the antifungal activity is elucidated by molecular docking. Coumarin derivatives were most effective against Macrophomina phaseolina and Sclerotinia sclerotiorum, but were not harmful against beneficial nematodes and bacteria. A predictive QSAR model was obtained for the activity against M. phaseolina (R2tr = 0.78; R2ext = 0.67; Q2loo = 0.67). A QSAR study showed that multiple electron-withdrawal groups, especially at position C-3, enhanced activities against M. phaseolina, while the hydrophobic benzoyl group at the pyrone ring, and –Br, –OH, –OCH3, at the benzene ring, may increase inhibition of S. sclerotiourum. Tested compounds possibly act inhibitory against plant wall-degrading enzymes, proteinase K. Coumarin derivatives are the potentially active ingredient of environmentally friendly plant-protection products.
A field investigation of olive trees in Istria, Croatia, revealed branch dieback and cracked bark. Samples of diseased branches were collected from eight different locations and analysed. ...Additionally, meteorological data from two locations were analysed to determine if there was a connection between climatic changes and the appearance of pathogens in the region. Pathogenicity tests were conducted on olive seedlings. This study provides a description of Biscogniauxia and Sordaria species’ morphology and elucidates their phylogeny based on the internal transcribed spacer (ITS), beta-tubulin (TUB2) and translation elongation factor 1-alpha (TEF1- α) regions. This research represents the first documented occurrence of Biscogniauxia mediterranea causing charcoal disease in olive trees in Croatia. Additionally, it is the first report of Biscogniauxia nummularia (Bull.) Kuntze and Sordaria fimicola causing diseases in olive trees anywhere in the world. Furthermore, this study marks one of the initial forays into molecular investigations of these species isolated from olive trees. Considering the potential threat posed by the inherent aggressiveness of Biscogniauxia species, further research is deemed necessary to curb the development of charcoal disease.
Occurrence of mycotoxins in food and beverages Petrović, Elena; Ćosić, Jasenka; Vrandečić, Karolina ...
Journal of Central European agriculture,
01/2023, Volume:
24, Issue:
1
Journal Article
Peer reviewed
Open access
This paper describes the mycotoxins produced by fungi from the genera Fusarium, Penicillium, Aspergillus, Claviceps and other types of molds, their characteristics and importance. Mycotoxins are ...secondary fungi metabolites that serve as a defense mechanism in stressful conditions. Several hundred mycotoxins have been identified so far, and the most significant in terms of danger to human health and animals are aflatoxins, ochratoxin A, patulin, fumonisin, zearalenone and nivalenol/deoxynivalenol produced by toxigenic fungi from the genera Penicillium, Aspergillus, Claviceps, Stachybotris and Fusarium. Moisture and temperature are two factors that have a crucial influence on the development of the fungus and the synthesis of toxins. It is estimated that approximately 25% of agricultural crops are infected with fungi. Consequently, foods can also be contaminated with mycotoxins. By treating the stored grain with various chemicals, and in recent years, using environmentally friendly fungicides, the synthesis of mycotoxins is being prevented and the development of mycotoxicogenic fungi is being controlled. The mycotoxicosis can occur directly through the consumption of infected food, inhalation and skin contact, or indirectly through animals that eat contaminated feed. Mycotoxins have a pathological effect primarily on liver. Some mycotoxins also interfere with cellular protein synthesis, causing hypersensitivity and extreme immunodeficiency. Despite mycotoxins being resilient and remaining stable while undergoing chemical and thermal food processing, methods such as applying good hygiene and production practices from field to table can reduce their occurence.
Vinova loza ubraja se u najvažnije kulture koje se uzgajaju u svijetu. Napada ju veliki broj fitopatogenih gljiva, među kojima se ističu i sve aktualnije postaju vrste iz porodice Botryosphaeriaceae. ...Simptomi se javljaju u obliku nekrotičnih lezija unutar drva, sušenja grozdova i sušenja mladica, krakova ili čitavih čokota. Bolest se češće uočava u starijim vinogradima. Najvažnije preventivne mjere podrazumijevaju sadnju zdravog sadnog materijala i izbor pogodne lokacije za uzgoj, a najvažnije izravne mjere zaštite podrazumijevanju uklanjanje zaraženih ostataka iz vinograda i njihovo uništavanje, primjenu fungicida i premazivanje rana nakon rezidbe te primjenu bioloških pripravaka za zaštitu bilja.
Dosadašnji načini kontrole uzročnika bolesti koji, među ostalim, podrazumijevaju uporabu fungicida prema novim zakonodavnim okvirima i novim strategijama u biljnom zdravstvu nailaze na sve veće ...restrikcije. Pronalaženje nekemijskih sredstava za zaštitu usjeva od biološki preparat, Fusarium graminearum, pšenica, zrnobolesti je od velikog interesa za poljoprivrednu proizvodnju, stoga je u našem istraživanju ispitan učinak novog biološkog preparata (BP) za kontrolu gljive Fusarium graminearum na klijancima pšenice. Biološki preparat primijenjen je na tri različita načina: inokulacijom zrna pšenice, zalijevanjem, te inokulacijom zrna i zalijevanjem. Utvrđeno je kako se intenzitet bolesti primjenom BP smanjuje, a najbolji rezultati dobiveni su inokulacijom zrna prije sjetve dok je zalijevanje površine BP polučilo slabije rezultate. Također, ukoliko je zrno već tretirano biološkim preparatom dodatna aplikacija zalijevanjem nije bila opravdana ni s ekološkog ni s ekonomskog aspekta.
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.
Vrsta Sclerotinia sclerotiorum (Lib.) De Bary najznačajniji je patogen koji uzrokuje značajne štete na uljaricama (suncokret, soja i uljana repica) širom svijeta. U područjima s vlažnijom i hladnijom ...klimom može doći do velikih ekonomskih gubitaka. Karakteristični simptomi su bijele prevlake micelija na zaraženim dijelovima biljaka i pojava sklerocija. Budući da efikasnih mjera zaštite nema, nužno je provoditi agrotehničke mjere suzbijanja.
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