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 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.

Effect of fungal solid-state fermented product enriched with gamma-linolenic acid and ß-carotene on blood biochemistry and immunology of broiler chickens.

The aim of this study was to investigate the effect of the addition of fungal solid-state fer-mented product (FP) enriched with gamma-linolenic acid (GLA) and ß-carotene to feed on the haematological and immunological parameters of broiler chickens. Eighty 1-day-old COBB 500 broiler chickens were divided into two groups. The control group was fed with basic diets and chickens of the experimental group received 10% addition of FP, while the amount of basic diet was reduced. FP was produced during a solid-state fermentation (SSF) process using Umbellopsis isabellina CCF2412 as a producer of GLA and ß-carotene. After 38 days of feeding, blood sam-ples were collected and analyzed. Lower total and LDL-cholesterol values were measured in blood samples of the experimental animals (p⟨0.05). However, the triacylglycerol content was higher in the experimental group (p⟨0.05). Significantly higher levels of hematocrit and hemo-globin, and lower eosinophil and basophil content in the experimental group were recorded (p⟨0.05). The experimental group showed higher numbers of B lymphocytes and greater phago-cytic capacity (p⟨0.05). The results indicate that a fermented product produced by SSF, using the fungal strain Umbellopsis isabellina, is a good source of GLA and ß-carotene, which can influence the biochemical, hematological and immunological parameters of broiler chickens.

Effect of fungal gamma-linolenic acid and beta-carotene containing prefermented feed on immunity and gut of broiler chicken.

Gamma-linolenic acid (GLA) is a fatty acid from the ω-6 family. It is able to deliver a wide range of health benefits arising from its anti-inflammatory effects. An insufficient supply of GLA from agricultural and animal sources resulted in the development of a fermentation technique using lower filamentous fungi, which have the ability to accumulate high concentrations of GLA and beta-carotene during solid-state fermentation of cereals. The goal of this study was to observe the influence of the addition of prefermented cereal product, containing high amounts of GLA and beta-carotene, into the feed of broiler chickens on their immune status, and also the number of lactic acid bacteria and enterobacteria in gut content, which has never been studied before. Immunostimulation in the GLA group was manifested by a significant increase in the oxidative burst of phagocytes, CD4+CD8- lymphocytes in blood, and the CD4: CD8 ratio. Upregulation of gene expression for IgA in the GLA group indicates that the B-lymphocytes were stimulated at a local gut level. In the caecum, increased mRNA expression for mucin-2 and insulin-like growth factor was observed in the GLA group, which could contribute mainly to the protection of the intestinal mucosa and to better growth and regeneration of skeletal muscles. Improved immune activation and protection of the intestinal mucosa were subsequently reflected in a change of the microbial composition in gut contents; a significant reduction of enterobacteria occurred after GLA administration. We can conclude that prefermented cereals containing fungal GLA and beta-carotene represent a low-cost supplement for broiler diet having a beneficial health effect.

The effect of supplementation of clove and agrimony or clove and lemon balm on growth performance, antioxidant status and selected indices of lipid profile of broiler chickens.

The study investigated the effects of diet supplementation with 1% clove flower buds powder combined with either 0.2% lemon balm extract or 0.2% agrimony extract (each of the two pulverized extracts supplied through drinking water) on body weight of broilers, total feed intake, feed conversion ratio and the carcass yield, activity of superoxide dismutase (SOD, EC 1.15.1.1) and glutathione peroxidase (GSH-Px, EC 1.11.1.9) in blood, concentration of sulfhydryl (-SH) groups, malondialdehyde (MDA), vitamin A and E, low-density lipoproteins in the blood plasma, serum cholesterol, total lipids, triglycerides and high-density lipoproteins in broiler chickens at 42 days of age. On the day of hatching, 120 male and female broilers of Cobb 500 were randomly divided into three groups. The control group (1st group) of broilers received a basal diet (BD) without any feed and water additive. Both experimental groups of chicks were fed BD enriched with clove (Syzygium aromaticum L.) powder at a dose of 10 g/kg DM for 42 days. Moreover, either lemon balm (Mellisa officinalis L.) extract or agrimony (Agrimonia eupatoria L.) extract diluted with drinking water (2:1000) was given to broilers in the 2nd and 3rd group respectively. The results indicated that feeding the diets enriched with selected herbal supplements failed to affect the growth performance of broiler chickens at 42 days of age. In addition, this supplementation had no influence on the activities of SOD and GSH-Px, concentration of vitamin A and selected lipid metabolism indices. On the other hand, we observed beneficial effects on some indices of the antioxidant status (increased concentration of -SH groups and vitamin E, decreased concentration of MDA) in the blood of broilers in both experimental groups in comparison with the control group of chickens (p < 0.05). Furthermore, a slightly better antioxidant capacity was found in the blood of broilers supplied the combination of clove and lemon balm compared to clove and agrimony (vitamin E, 11.26 ± 0.73 vs. 9.73 ± 0.64 µmol/L, p < 0.05 respectively). It could be concluded that supplementation of the diet with clove flower buds powder combined with lemon balm extract or agrimony extract dissolved in drinking water has a potential to increase the antioxidant status but fails to influence either the growth performance or the selected lipid metabolism indices of broilers at the age of 42 days.