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1.
Animals (Basel) ; 13(24)2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38136820

RESUMO

The aim of the study was to evaluate the potential of using five selected species of entomopathogenic fungi (Beauveria bassiana, B. brongniartii, Conidiobolus coronatus, Isaria fumosorosea, and Metarhizium robertsii) in the bioregulation of the dispersive stages of the parasitic nematode-Ascaris suum. Experimental cultures of each of the selected entomopathogenic fungi, as well as a control culture without fungi, were incubated with A. suum eggs at 26 °C for 28 days. Development of the A. suum eggs was observed using a light microscope on the 7th, 14th, 21st, and 28th days of incubation. The API-ZYM® test was used to determine, semiquantitatively, the activity of 19 hydrolytic enzymes from the entomopathogenic fungi. The cytotoxicity of the fungi was determined using tetrazole salt MTT. It was found that none of the five tested strains of entomopathogenic fungi showed an ovicidal effect, and none of them colonized the A. suum egg shells. However, ovistatic activity was observed mainly until the 14th day of incubation by I. fumosorosea, M. robertsii, and B. bassiana. In the MTT test, M. robertsii showed moderate cytotoxicity, while the other species showed low cytotoxicity. Among the strains tested, I. fumosorosea showed the highest spectrum of hydrolase production (13 out of 19 enzymes gave a positive reaction from 3 to 5; 20-40 nM or more). The absence of morphological changes in the A. suum egg shells suggests that the antagonistic effect of the studied entomopathogenic fungi may be due to their cytotoxicity, associated with the production of secondary metabolites-toxins (M. robertsii) and enzymatic activity (I. fumosorosea).

2.
Materials (Basel) ; 14(18)2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34576543

RESUMO

Agro-industrial by-products are promising source of biopolymers, including proteins and polysaccharides. This study was designed to evaluate the flaxseed oil cake extract (FOCE) as natural encapsulating material and carrier for probiotic Lacticaseibacillus rhamnous GG (LGG). The powders were obtained using three spray drying inlet temperatures (110 °C, 140 °C, 170 °C), and reconstituted. The influence of temperature on water activity, morphology, chemical composition, flowability and cohesiveness of the powders was estimated. For all variants, the survival of bacteria during spray drying, and simulated passage through the gastrointestinal tract was evaluated. The preservation of LGG probiotic features such as cholesterol reduction, hydrophobicity and adhesion to mucin were examined. Results revealed that all physicochemical and functional characteristics of the powders were affected by the inlet temperature. This study demonstrated that FOCE is an appropriate matrix for spray drying (due to flaxseed proteins and polysaccharides) providing high survivability of bacteria (89.41-96.32%), that passed meaningfully through the simulated gastrointestinal tract (4.39-5.97 log reduction), largely maintaining their probiotic properties, being a promising environmentally-friendly carrier for probiotic LGG.

3.
Microorganisms ; 8(9)2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32825460

RESUMO

This study aimed at investigating the antioxidant activity, oxidative stability, physicochemical and microbial changes of innovative vegan Camembert-analogue based on flaxseed oil cake (FOC) which was produced using lactic acid bacteria (LAB), mold Penicillium camemberti (PC) and yeast Geotrichum candidum (GC). Two variants were prepared, namely with LAB + PC and LAB + PC + GC. After fermentation for 24 h at room temperature, the samples were stored for 14 days at 12 °C and maturated for 14 days at 6 °C. Changes in microbial population, polyphenolics, flavonoids, radical scavenging capacity were evaluated. Additionally, textural changes, pH, acidity, levels of proteins, free amino acids, reducing sugars, oil content and its oxidative stability were determined. Results showed that LAB as well as fungi were capable of growing well in the FOC without any supplementation and the products were characterized by a high antioxidant potential (high polyphenolics and flavonoids contents as well as 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), superoxide (O2-) and hydroxyl (·OH) radicals scavenging activity). This study has demonstrated that bioactivity as well as the physicochemical properties depend on the starter culture used. Due to functional and biochemical characteristics conferred to the obtained Camembert-analogues, the use of P. camemberti and G. candidum showed a potential for industrial application. There is a potential for these products to be used where non-dairy alternatives are desired.

4.
Ann Parasitol ; 60(3): 215-20, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25281819

RESUMO

The study aim was to compare the antagonistic interaction between saprotrophic soil fungi and embryonic development of geohelminths Toxocara canis and Ascaris suum. The experimental cultures were fertilized eggs of T.canis and A. suum incubated together with mycelium of strains: Fusarium culmorum, Metarhizium anisopliae,Paecilomyces fumosoroseus, Trichoderma viride and Trichothecium roseum. In the control cultures the eggs of both nematode species were incubated without fungi. The experiment was conducted at temp. 26°C for 60 days. Compared with the control, all of the tested species of fungi significantly extended the embryonic development of both T. canis and A. suum. Most inhibitory effect on the rate of embryonic development of T. canis and A. suum had three fungal species: P. fumosoreus, M. anisopliae and T. viride. Compared with the control, on the 60th day of incubation in the presence of each of the tested fungal species, a larger percentage (p<0.05) of morphological abnormalities was stated in developing embryos of T. canis (49­69%) than in A. suum (15.1­67.7%). Among the examined fungal species, only incubation with P. fumosoroseus resulted in significantly greater (p<0.05) incidence of embryonic malformations(embryopathies) in T. canis, as compared with A. suum. Also the percentage of dead larvae of T. canis in the control and in cultures with fungi (12% and 100%, respectively) was significantly higher in comparison with A. suum (0.5% and 10.3­36%, respectively). The highest percentage of non-viable larvae of A. suum was found in the presence of P.fumosoroseus, and the lowest in the presence of M. anisopliae. Findings may indicate that T. canis eggs are more sensitive to antagonistic interaction of the examined fungal strains than A. suum eggs.


Assuntos
Ascaris suum/microbiologia , Fungos/classificação , Fungos/fisiologia , Toxocara canis/microbiologia , Animais , Controle Biológico de Vetores , Microbiologia do Solo
5.
Folia Biol (Krakow) ; 62(2): 149-54, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25134345

RESUMO

The aim of this study was to determine the effect of 6 common soil fungi species: Alternaria alternata (Fr.) Keissl., Aspergillus candidus Link, Penicillium chrysogenum Thom, P. commune Thom, Trichothecium roseum (Pers.) Link and Ulocladium sp., on the hatching of miracidia, i.e., free living larvae of liver fluke (Fasciola hepatica). To this end, the eggs of F. hepatica were incubated in water in the presence of one of the aforementioned fungi species and in tap water (control) at a temperature of 26 degrees C. At the 15th day of incubation we determined the number of nonembryonated, embryonated and hatched eggs. We observed different degrees of antagonistic influences by the tested fungal strains on the development of F. hepatica eggs. Among the examined fungi, the strongest ovistatic effects were exhibited by Trichothecium roseum, Penicillium chrysogenum (R-3) and P. commune. The study showed no morphological damage to the shells of the F. hepatica eggs which may suggest a biochemical basis of antagonistic interactions by the fungi associated with the activity of fungal enzymes, mycotoxins and antibiotics. Low or no activity of peptide hydrolases in Penicillium chrysogenum and P. commune in the API ZYM test suggests their insignificant role in the degradation of shell proteins ofF. hepatica eggs.


Assuntos
Fasciola hepatica/fisiologia , Fungos/fisiologia , Interações Hospedeiro-Parasita , Animais , Fungos/crescimento & desenvolvimento
6.
Wiad Parazytol ; 55(1): 1-8, 2009.
Artigo em Polonês | MEDLINE | ID: mdl-19579778

RESUMO

The state of knowledge on the possible antagonism between soil saprotrophic fungi and phytopathogenic nematodes of the genera Meloidogyne, Heterodera, and Globodera is reviewed basing on the literature and our own research. Mycelial colonisation of various developmental stages of these geohelminths is the most common factor thought to reduce their populations in nature. The following parasitic fungi can be found on the cysts, eggs, as well as the larvae of the nematodes: Paecilomyces lilacinus, Verticillium chlamydosporium, Cylindrocarpon destructans, Pochonia chlamydosporia, Fusarium spp., and Penicillium spp. The fungi invade the nematodes, such as Heterodera, Globodera, or Meloidogyne, "passively" penetrating through the natural orifices of the cysts, eggs, and larvae of the host. Equally frequent, however, is a biochemical action of the fungi prior to colonisation, which is linked with production of mycotoxirls or hydrolytic enzymes. Such an active way of fungal penetration of various stages of the phytopathogenic nematodes has been observed in Pochonia chlamydosporia, Penicillium verrucosum var. cyclopium, P. frequentans, Sclerotinia rolfsii, Rhizoctonia solani, and Fusarium spp. Triacylglycerols (TAG), phenols, as well as trichothecene, T-2, have been found in the metabolites extracted from mycelia of these species. Predation by fungi is also a factor that may reduce a population of phytopathogenic nematodes. This form of antagonism is characteristic for nematicidal fungi of the genera Arthrobotrys and Dactylella. These fungi form shrinking rings and hooks in their mycelia by which the fungus entangles and paralyses a migrating form of nematode. Despite the fact that the antagonism between fungi and nematodes is a commonly occurring phenomenon observed in the soil, the nematicidal and nematotoxic properties of fungi have not a wide application in biological plant protection. Up till now, only the bionematicides based on Arthrobotrys robusta (Royal 300 and Royal 350) as well as Paecilomyces lilacinus (Biocon and PL Plus) have found its commercial application.


Assuntos
Fungos/fisiologia , Nematoides/microbiologia , Controle Biológico de Vetores/métodos , Microbiologia do Solo , Solo/parasitologia , Animais , Interações Hospedeiro-Parasita
7.
Wiad Parazytol ; 55(1): 9-17, 2009.
Artigo em Polonês | MEDLINE | ID: mdl-19579779

RESUMO

The soils ecosystem plays an important role in the epidemiology of geohelminth diseases of humans and animals. Soil contamination with ova of the parasitic geohelminths represents a global public health-hazard issue. Biological agents have been thought to control the infective forms of parasites present in the soil. Biocontrol of geohelminths represents an alternative to pesticides (i.e., nematicides), which are not efficient in killing infective nematode forms and, additionally, result in the environment pollution and long-term disturbances in the soil ecosystem homeostasis. The degree of the inhibiting effect of soil saprotrophic fungi on geohelminth embryonic development varies and depends on the species. A number of fungi cause various morphological disorders in the embryos of developing parasitic nematodes, but also have an ovicidal effect. Although the nature of the antagonism between fungi and other living organisms has not been fully explained, it is certain that mycotoxins and fungal enzymes constitute its important components. Considering the studies carried out so far, the antagonistic effect of mold fungi against the infective stages of geohelminths can be fully recommended as a real control factor, especially as these saprotrophs represent a natural factor within the soil environment, that is of particular biochemical activity.


Assuntos
Fungos/fisiologia , Nematoides/microbiologia , Controle Biológico de Vetores/métodos , Microbiologia do Solo , Solo/parasitologia , Animais , Interações Hospedeiro-Parasita , Humanos , Nematoides/embriologia , Infecções por Nematoides/prevenção & controle , Infecções por Nematoides/veterinária
8.
Ann Acad Med Stetin ; 52(1): 19-23; discussion 23, 2006.
Artigo em Polonês | MEDLINE | ID: mdl-17131843

RESUMO

PURPOSE: The present study focused on the effect of two fungal species Metarhizium flavoviride and Metarhizium anisopliae on the embryonic development and viability of Ascaris suum larvae. RESULTS: Microscope examination revealed that the presence of the mycelium inhibited the egg development, compared to control. The fungus-exposed eggs featured zygote vacuolisation, irregular blastomere cleavage, and morphological disturbances in the stages of blastula, gastrula, and larva. The embryopathies were significantly more frequent in the eggs incubated with M. flavoviride. Also the mortality of the developed larvae was significantly higher after 60-day culture with M. flavoviride.


Assuntos
Ascaris suum/embriologia , Ascaris suum/microbiologia , Metarhizium/fisiologia , Controle Biológico de Vetores , Animais , Desenvolvimento Embrionário , Interações Hospedeiro-Parasita , Humanos/parasitologia , Larva/crescimento & desenvolvimento , Larva/microbiologia , Metarhizium/patogenicidade , Óvulo/crescimento & desenvolvimento , Óvulo/microbiologia , Zigoto/crescimento & desenvolvimento , Zigoto/microbiologia
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