Essential oil and plant extract of oregano as agents influencing the virulence factors of Candida albicans.

Candida albicans, a polymorphic yeast, is a physiological component of the human and animal commensal microbiome. It is an etiological factor of candidiasis, which is treated by azole antifungals. Growing resistance to azoles is a reason to look for other alternative treatment options. The pharmacotherapeutic use of plant extracts and essential oils has become increasingly important. In our experiment, C. albicans showed susceptibility to four observed plant extracts and essential oils from peppermint ( Mentha piperita), thyme ( Thymus vulgaris), sage ( Salvia officinalis), and oregano ( Origanum vulgare). Oregano plant extract and essential oil showed the highest antifungal activity, at MIC values of 4.9 mg/mL and 0.4 mg/mL respectively. Therefore, it was subjected to further research on the influence of virulence factors - biofilm formation, extracellular phospholipase production and germ tube formation. Oregano plant extract and essential oil showed an inhibitory effect on the observed C. albicans virulence factors at relatively low concentrations. The extract inhibited the adherence of cells at MIC 12.5 mg/mL and essential oil at MIC 0.25 mg/mL. Degradation of the formed biofilm was detected at MIC 14.1 mg/mL for plant extract and at MIC 0.4 mg/mL for essential oil. Extracellular phospholipase production was most effectively inhibited by the essential oil. In particular, the number of isolates with intensive extracellular phospholipase production decreased significantly. Of the 12 isolates intensively producing extracellular phospholipase, only 1 isolate (4.5%) retained intense production. Essential oil caused up to a 100 % reduction in germ tubes formation and plant extract reduced their formation depending on the concentration as follows: 2.6% (0.8 mg/mL), 21.2 % (6.25 mg/mL), and 64.5 % (12.5 mg/mL) compared to the control.

Efficacy of manuka honey with conventional antifungals on Malassezia pachydermatis.

Yeast infections such as otitis externa and seborrheic dermatitis in dogs and cats are frequently associated with Malassezia pachydermatis secondary infection. It is part of the normal cutaneous microflora of most warm-blooded vertebrates, however, under certain conditions, it can become a causative agent of infection that needs to be treated pharmacologically. Azole derivatives are the drugs of the first choice. An interesting trend in developing resistance is the use of natural substances, which include manuka honey with confirmed antimicrobial properties. The main intention of this research was to evaluate the mutual effect of manuka honey in combination with four conventional azole antifungals - clotrimazole, fluconazole, itraconazole, and miconazole - on 14 Malassezia pachydermatis isolates obtained from dogs and 1 reference strain. A slightly modified M27-A3 method (CLSI 2008) and the checkerboard test (Nikolic et al. 2017) were used for this purpose. Our results show an additive effect of all 4 antifungals with manuka honey concurrent use. Based on the determined values of fractional inhibitory concentration index (FICI - 0.74±0.03 when manuka honey combined with clotrimazole, 0.96±0.08 with fluconazole, 1.0±0 with miconazole and 1.16±0.26 with itraconazole), it was found in all cases that the effect of substances used is more pronounced in mutual combination than when used separately.

In vitro evaluation of zearalenone toxicity by comet assay.

The aim of this study was to reveal the potentially genotoxic effect of zearalenone on bovine lymphocytes by comet assay in vitro. The bovine lymphocytes were exposed to various zearalenone concetrations (50; 10; 2; 0.4 and 0.08 ppm). The viability and DNA damage of lymphocytes was monitored after 2 h, 24 h, 48 h and 72 h. After 2 hours of zearalenone exposure, statistically significant DNA damage occurred at all tested concentrations of 0.08 ppm (12.2±1.25; p⟨0.05), 0.4 ppm (12.7±0.88; p⟨0.01), 2 ppm (12.0±0.51; p⟨0.01), 10 ppm (11.2±0.47; p⟨0.01) and at 50 ppm (14.2±0 61; p⟨0.001). Significantly greater DNA damage was also found after 24 h, 48 h and 72 h. The obtained results showed that zearalenone may induce DNA damage of the bovine lymphocytes.

Efficacy of Lamiaceae essential oils with selected azoles against Candida albicans clinical isolates.

A current problem in candidiasis treatment is increasing resistance to azoles, which are often prescribed to patients. The study underlines the high resistance of yeasts to fluconazole, which achieved high MIC (minimal inhibitory concentration) values both alone and in combination with essential oils (EOs). Antifungal activity of Hyssopus officinalis, Thymus vulgaris, Salvia officinalis and Rosmarinus officinalis EOs was determined against 13 clinical isolates of Candida albicans and reference strain Candida albicans ATCC 10231. The synergistic effect was investigated for the combination of itraconazole and fluconazole with Hyssopus officinalis and Thymus vulgaris EOs. Based on the fractional inhibitory concentration index, the synergistic effect was achieved in all of the samples exposed to itraconazole with Hyssopus officinalis (FICI 0.3±0.06). On the other side, the additive effect was proven in use of itraconazole with Thymus vulgaris (FICI 0.75±0.35) and fluconazole with both EOs tested (FICI 0.81±0.19; 0.88±0.57) This study shows the importance of monitoring the synergistic effect of antifungals combined with EOs, because it is a possible solution for reducing the resistance and improving the disease prognosis.

A rare case of urethral hemangioma treated with LASER.

Hemangiomas are benign vascular lesion, most commonly seen in liver and skin. Urethral hemangiomas are very rare benign vascular tumors with varying size and usually present as urethral bleeding or hematuria. We are presenting a 64 years old male, who was admitted to our Urology Department with symptoms of intermittent urethral bleeding for 6 months. We performed flexible cystoscopy under general anesthesia and a single hemangiomatous lesion of 7 mm in diameter located in the navicular fossa was found. The SIRIUS 60W Thulium Fiber Laser for removing the lesion was used.

Interactions between Clotrimazole and selected essential oils against Malassezia pachydermatis clinical isolates.

The aim of this study was to investigate interactions between conventional antifungal drug and essential oils against isolates of Malassezia pachydermatis. Antifungal activity of Cinnamomum cassia, Melaleuca alternifolia, Mentha piperita, Origanum vulgare and Syzygium aromaticum essential oils were tested against 19 strains of M. pachydermatis isolated from healthy dogs and reference strain M. pachydermatis CBS 1879. The checkerboard assay was used to search for in- teractions. Synergism was observed for the combination of clotrimazole with Melaleuca alternifolia essential oil, Mentha piperita and Origanum vulgare. The combinations of Cinnamomum cassia and Syzygium aromaticum essential oils with clotrimazole showed indifferent effect. Additive antimicrobial activity was observed for the combination of clotrimazole with Syzygium aromaticum and Melaleuca alternifolia essential oils against reference strain. The obtained results showed synergistic interactions between essential oils and clotrimazole which could improve effectiveness of this antifungal drug.

Effectiveness of selected disinfectants on Malassezia pachydermatis.

The present study investigated the effectiveness of three different disinfectants: preparation H1 (two-component preparation based on hydrogen peroxide); Pedox (multi-component preparation based on peroxyacetic acid) and Savo hypochlorite preparation) against Malassezia pachydermatis. The antifungal activity of disinfectants was tested by quantitative suspension method according to STN EN 1650. The results confirmed 100% effectiveness of these disinfectants at all concentrations and exposure times tested.

Fusarial toxins and their role in animal diseases.

Fusarial toxins are toxic metabolites produced mostly by toxigenic micromycetes of genus Fusarium. Dominant mycotoxins of this group include trichothecenes, moniliformin, zearalenone, and fumonisins. Recently, special attention has been paid to these toxins because of their harmful effects on both animals and humans. On the basis of the available literature, we review here the characteristics of major fusarial mycotoxins with an emphasis on their toxic effects on animals. The most important fusarial mycotoxins, their sources, and their pathology including clinical signs, necropsy findings, as well as changes in haematological, biochemical, and immunological indices, are addressed.

Immune response of E. cuniculi infected mice to aflatoxin B1.

The immunomodulatory effects of aflatoxin B1 (AFB1) on mice experimentally infected with Encephalitozoon cuniculi (E. cuniculi) were studied. Mice inoculated intraperitoneally with spores of E. cuniculi drank a daily solution of AFB1 (0.2 mg kg(-1) of body weight) for 27 days. Application of AFB1 to mice demonstrated a decrease of immunocompetent cells. On the other hand, the mice infected with E. cuniculi and given AFB1 showed significant increased number of both monocytes and CD8+ T cells, and tendency to a decrease in CD4+ T cells. Aflatoxin B1 revealed to merely modulate systemic immune response of E. cuniculi infected mice.

Effect of aflatoxin B1 on CD3 T cells and alkaline phosphatase in the intestine of mice.

The aim of the study was to determine the effect of repeated applications of aflatoxin B1 (AFB1) on immunocompetent cells (CD3 T cells) and alkaline phosphatase in the intestinal mucosa. Mice were orally treated with AFB1 for 24 days. The mucosa of the intestine showed a significant decrease in the number of CD3 T cells and a significantly lower level activity of alkaline phosphatase on day 24 in AFB1 treated mice. Similarly, with changes in the small intestine, qualitative haematological parameters were modified in systemic immunity as lymphopenia, and neutropenia, monocytopenia. AFB1 treated animals showed reduction in body weight gain and increased liver weight. We supposed that changes found in the small intestine are secondary to primary systemic haematological lesions. The decrease in CD3 T cells suggests a connection with the decrease in the host's resistance to infectious diseases.

The effect of zearalenone on some enzymatic parameters in rabbits.

The effects of low (10 microg/kg b.w.) and high (100 microg/kg b.w.) doses of mycotoxin-zearalenone on selected blood serum enzyme activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), gamma-glutamyltransferase (GGT), and total lactatedehydrogenase (LD) of rabbits were studied. The toxin was administered orally for 14 days. In the experimental group E(1) (10 microg/kg b.w.), a significant increase in ALP activity was observed at 168 and 336 h during the experiment. In the 100 microg zearalenone sera (group E(2)), significant increases in activities of AST, ALT, ALP, GGT, and LD were observed at 168 and 336 h, indicating possible liver toxicity due to chronic effects of the toxin.

The use of yeast for microbial degradation of some selected mycotoxins.

Several biodegradation experiments were carried out using 10 different yeast strains.Saccharomyces spp., Kluyveromyces spp. andRhodotorula spp. were tested for biodegradation of selected mycotoxins (ochratoxin A, nivalenol, deoxynivalenol and fumonisin B1) standardsin vitro. There was confirmed that some yeast strains are able to degrade some mycotoxins. However, great differences between individual strains were observed. Moreover, 12Saccharomyces cerevisiae strains were tested for their potential capability to degrade zearalenone and fumonisins in Sabouraud broth. Two strains were capable to degrade zearalenone totally, one strain decreased the mycotoxin concentration up to 25%, and one strain up to 75% of original amount. Two strains were capable to degrade fumonisins partially.

[The bioclimate in housing for broilers and its effect on mycotic contamination]. / Bioklíma výkrmne brojlerových kurciat a jej vplyv na mykotickú kontamináciu.

Consequences between climate parameters of stable environment and mould occurrence were monitored during one fattening cycle. Xerophilic and hydrophilic species of moulds were diagnosed in the stable air. Their presence was especially influenced by contaminated feeding mixtures and litter. Mostly the "storage" species of moulds (Penicillium, Aspergillus) but also the "field" species (Fusarium, Alternaria) were isolated from the feeding mixtures. Xerophilic Penicillium species as well as hydrophilic species, e.g. Cladosporium dominated in litter in the beginning of the cycle. Yeasts dominated in the end of the cycle. In examined samples of sedimented dust, the highest frequency of occurrence was in Penicillium germs.

Occurrence of Fusarium sacchari var. subglutinans and its mycotoxin production ability in broiler feed.

Spores of Fusarium sacchari var. subglutinans isolated from broiler feed BR1 were obtained at an average concentration of 1.5/mg in 25% of tested samples. The spore concentration was increased from 1 to 100/mg of solid substrate (BR2; biscuit) or to 1/nL of Sabouraud broth after 3 weeks of cultivation. Mycotoxin analyses of these three substrates showed negative reactions for T-2 toxin and zearalenone but a positive reaction for deoxynivalenol (DON) which was found in concentrations of 5 ppm in Sabouraud broth, 50 ppm in BR2 and 220 ppm in biscuit. Therefore, our F. sacchari isolate appeared to be a DON producer.

[Inhibition of growth of microscopic fungi with organic acids]. / Inhibícia rastu niektorých mikroskopických húb vybranými organickými kyselinami.

Fungicidal effects of five selected organic acids (lactic, acetic, formic, oxalic, and propionic) in concentrations 3, 5, 10, 20 and 50 ml/l on nine selected species of moulds were tested. Lactic and oxalic acids did not prove the satisfactory fungicidal activity in any of the chosen concentrations. The antifungal effect of the other three acids, manifested by the growth inhibition of the tested moulds is shown in Tab. I and it can be expressed by sequence: propionic acid, formic acid, and acetic acid. These acids also had effects only in concentrations 20 ml/l and 50 ml/l. Propionic acid in concentration 20 ml/l inhibited the growth of five moulds (Penicillium glabrum, Aspergillus niger, Fusarium moniliforme, Aspergillus fumigatus, Cladosporium sphaerospermum). In testing of concentration 50 ml/l, the lower fungicidal ability was ascertained only in growth suppression of Aspergillus flavus. The fungicidal activity of formic acid was registered in concentration 20 ml/l in two cases and in concentration 50 ml/l in six cases. Acetic acid inhibited the growth in concentration 50 ml/l only in two cases. Tab. II shows the percentual evaluation of propionic acid and formic acid with regard to their inhibition abilities. The fungicidal efficiency of propionic acid resulting from the experiment is 88.9%.