scholarly journals Survey of mycobiota on Slovakian wine grapes from Small Carpathians wine region

10.5219/1322 ◽  
2020 ◽  
Vol 14 ◽  
pp. 721-728
Author(s):  
Soňa Felšöciová ◽  
Kačániová Miroslava ◽  
Vrábel František

A total of 13 samples of grapes (bunches) without apparent fungal contamination were analyzed. The samples were collected during the 2019 harvest from Vrbové village in the Small Carpathian region of Slovakia. For the isolation of fungi were used the direct plating technique on DRBC plates. The plates were incubated aerobically at 25 ±1 °C for one week in the dark. The data obtained from the cultivation of the grape berry samples revealed a high diversity of fungal species (a total of 1044 isolates were obtained). Alternaria and Rhizopus were the main components of the wine grape mycobiota of the Vrbovský subregion at harvest time (92%, each), followed by Cladosporium (85%), Penicillium (77%), Botrytis and Epicoccum (54%, each). The most abundant genera found by descending order were Penicillium (25%), Alternaria (24%), Cladosporium (20%), and Rhizopus (12%) and only in minor percentage by Aspergillus (3%) among others. The main fungal species isolated from genera Penicillium and Aspergillus were Penicillium expansum (57% RD) and A. section Nigri (97% RD). Of 17 analyzed Penicillium strains, 65% were able to produce at least one of the six mycotoxins analyzed in in vitro conditions by means of thin-layer chromatography method: citrinin, griseofulvin, patulin, cyclopiazonic acid, penitrem A, and roquefortin C.

10.5219/1044 ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 194-199
Author(s):  
Soňa Felšöciová ◽  
Miroslava Kačániová

The diversity of mycobiota associated with grapevine in Vrbove, Slovakia at the harvest time in 2018 was evaluated. Fourteen samples of grapes were analyzed by plating methods and by plating methods with surface disinfection. The identification of fungi was performed using the morphological and microscopical characteristics. From the 1001 strains detected and identified from exogenous mycobiota, the most frequent genera were Alternaria, Rhizopus and Sordaria. Their relative density was low, except Alternaria. The most frequently encountered moulds and with the highest relative density from endogenous mycobiota were Alternaria, Cladosporium and Penicillium. Most of all genera had relative density less than 1%. Penicillium contributed small proportion in both sources. Penicillium citrinum was the most dominant species in exogenous and endogenous mycobiota. Penicillium expansum and P. glabrum were recorded in exogenous source and P. hordei, P. chrysogenum and P. griseofulvum in endogenous. Potentially toxigenic Penicillium species were tested for their toxigenic ability by thin layer chromatography method. Out of 15 tested isolates representing five potentially toxigenic species 11 produced at least one mycotoxin. Positive toxinogenity was detected in all tested strains of Penicillim citrinum (9/9).


2020 ◽  
Vol 8 (1) ◽  
pp. 69 ◽  
Author(s):  
Marco Camardo Leggieri ◽  
Amedeo Pietri ◽  
Paola Battilani

No information is available in the literature about the influence of temperature (T) on Penicillium and Aspergillus spp. growth and mycotoxin production on cheese rinds. The aim of this work was to: (i) study fungal ecology on cheese in terms of T requirements, focusing on the partitioning of mycotoxins between the rind and mycelium; and (ii) validate predictive models previously developed by in vitro trials. Grana cheese rind blocks were inoculated with A. versicolor, P. crustosum, P. nordicum, P. roqueforti, and P. verrucosum, incubated at different T regimes (10–30 °C, step 5 °C) and after 14 days the production of mycotoxins (ochratoxin A (OTA); sterigmatocystin (STC); roquefortine C (ROQ-C), mycophenolic acid (MPA), Pr toxin (PR-Tox), citrinin (CIT), cyclopiazonic acid (CPA)) was quantified. All the fungi grew optimally around 15–25 °C and produced the expected mycotoxins (except MPA, Pr-Tox, and CIT). The majority of the mycotoxins produced remained in the mycelium (~90%) in three out of five fungal species (P. crustosum, P. nordicum, and P. roqueforti); the opposite occurred for A. versicolor and P. verrucosum with 71% and 58% of STC and OTA detected in cheese rind, respectively. Available predictive models fitted fungal growth on the cheese rind well, but validation was not possible for mycotoxins because they were produced in a very narrow T range.


2005 ◽  
Vol 95 (11) ◽  
pp. 1271-1278 ◽  
Author(s):  
Raffaello Castoria ◽  
Valeria Morena ◽  
Leonardo Caputo ◽  
Gianfranco Panfili ◽  
Filippo De Curtis ◽  
...  

Contamination of apples (Malus domestica) and derived juices with fungicide residues and patulin produced by Penicillium expansum are major issues of food safety. Biocontrol agents represent an alternative or supplement to chemicals for disease control. Our data show that these microbes could also contribute to actively decreasing patulin accumulation in apples. Three biocontrol agents, Rhodotorula glutinis LS11, Cryptococcus laurentii LS28, and Aureobasidium pullulans LS30, were examined for their in vitro growth in the presence of patulin and for their capability to decrease mycotoxin recovery from the medium. Strain LS11 yielded the highest growth rates and the greatest decrease of toxin recoveries. Further, it caused the appearance of two major spots on thin-layer chromatography (TLC) plates, suggesting possible metabolization of the mycotoxin. In vivo, i.e., in the low percentage of LS11-pretreated apples infected by P. expansum, patulin accumulation was significantly lower than in nontreated infected fruits. Yeast cells survived and increased in infected apples and, in a model system emulating decaying apple, resulted in accelerated breakdown of patulin and the production of the same TLC spots as those detected in vitro. These data suggest that biocontrol yeast cells surviving in decaying apples could metabolize patulin and/or negatively affect its accumulation or synthesis. To our knowledge, this is the first report describing the effect of a biocontrol agent on patulin accumulation in vivo.


2019 ◽  
Vol 13 (2) ◽  
pp. 120-128
Author(s):  
Amal Thebti ◽  
Ines Chniti ◽  
Med Abderrahmane Sanhoury ◽  
Ikram Chehidi ◽  
Hadda Imene Ouzari ◽  
...  

Background:The widespread occurrence of resistance to current antibiotics has triggered increasing research efforts to design and develop innovative antibacterial and antifungal agents that could overcome such antimicrobial resistance.Objective:The aim of this work was the in vitro evaluation of twelve highly fluorinated Nmonosubstituted thiocarbamates and dithiocarbamates and six non-fluorinated analogs against nine bacterial strains and three fungal species.Methods:The in vitro antimicrobial activity against the tested microrganisms was evaluated using the microdilution broth method.Results:Escherichia coli ATCC 8739, Salmonella sp., Staphylococcus aureus 6539 and all the three fungi (Aspergillus niger, Aspergillus flavus and Penicillium expansum) exhibited the highest rate of susceptibility, whilst Enterococcus faecuim ATCC 19436 and particularly Escherichia coli DH5α were less susceptible. Thiocarbamate (1i) and dithiocarbamate (2i) showed both the lowest MIC values (3.9 µg/mL) and the widest spectrum of antibacterial activity. Furthermore, the N-ethyl derivatives inhibited more efficiently the growth of bacteria than N-aryl analogs.Conclusion:The fluorinated compounds showed, in general, a relatively more potent antibacterial activity than non-fluorinated counterparts. The results indicate that these thiocarbamates and dithiocarbamates could be promising candidates as potential antimicrobial agents.


1999 ◽  
Vol 62 (3) ◽  
pp. 292-294 ◽  
Author(s):  
MARIA LÍGIA MARTINS ◽  
HERMÍNIA MARINA MARTINS

Eighty samples of animal feeds of different origins were screened for the natural co-occurrence of cyclopiazonic acid (CPA) and aflatoxins in Portugal. Forty-five strains of Aspergillus flavus were collected from those samples and studied for their ability to produce these mycotoxins, in vitro. CPA was detected by thin-layer chromatography using Erhlich's reagent for confirmation. Aflatoxins were determined by high-pressure liquid chromatography with postcolumn iodination. Only 5 of the 80 samples (6.2%) were naturally contaminated with cyclopiazonic acid (0.16 mg/kg) and 36 (45.0%) with aflatoxin B1 (AFB1) (from 0.001 to 0.016 mg/kg). An in vitro study of the 45 strains of A. flavus was performed in cracked corn at 25°C (water activity, aw = 0.96), incubated for 21 days to CPA production. For in vitro production of aflatoxins, the same substrate was incubated at 28°C for 14 days. Nineteen of the strains (42.2%) produced CPA (ranging from 0.5 to 1.45 mg of CPA/kg) and 23 of them (51.1%) produced AFB1 (from 0.001 to 0.844 mg/kg). Only 10 isolates (22.2%) produced both CPA and AFB1 (0.05 to 0.10 mg/kg and 0.001 to 0.230 mg/kg, respectively). Thirteen strains did not produce either CPA nor AFB1.


2021 ◽  
Vol 14 (1) ◽  
pp. 27-33
Author(s):  
Florina Căpățină ◽  
◽  
Eva Suciu ◽  
Daniela Benedec ◽  
◽  
...  

Objectives. Thymus species, T. vulgaris, T. serpyllum, T. comosus and T. glabrescens, are medicinal plants from the spontaneous Romanian flora used for their antibacterial, antispasmodic, expectorant, anti-inflammatory, anthelmintic properties, especially the plant products obtained from T. vulgaris. The aim of this study was to comparatively investigate the polyphenolic composition, as well as the in vitro antioxidant activity of some ethanolic extracts obtained from the aerial parts of thymus sp. Materials and methods. The polyphenols, flavonoids, phenolic acids and tannins contents in the four samples thymus sp. ethanolic extracts were spectrophotometrically determined. The identification of the most important polyphenolic compounds was performed by the method of thin layer chromatography method (TLC). The antioxidant activity of hydroalcoholic extracts was evaluated in vitro by the DPPH method. Outcomes. Following the analyzes performed, it can be revealed that there are both qualitative and quantitative differences in the polyphenolic composition of the four species of thyme studied, the richest in active principles being T. vulgaris and T. serpyllum. Conclusions. In this paper it has been shown that thyme species are medicinal plants rich in antioxidant polyphenolic active principles, and their use for the treatment of certain diseases can be justified. In addition to the officinal species: T. vulgaris, T. serpyllum, other thyme species from the spontaneous flora of our country can be used in phytotherapy, such as: T. comosus, T. glabrescens.


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