• Journal of Microbiology and Biotechnology
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• v.27 no.2
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• pp.395-404
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• 2017

Fungal cell walls and cell membranes are the main targets of antifungals. In this study, we report on the antifungal activity of an ethanol extract from Paeonia lactiflora against Candida albicans, showing that the antifungal activity is associated with the synergistic actions of preventing cell wall synthesis, enabling membrane depolarization, and compromising permeability. First, it was shown that the ethanol extract from P. lactiflora was involved in damaging the integrity of cell walls in C. albicans. In isotonic media, cell bursts of C. albicans by the P. lactiflora ethanol extract could be restored, and the minimum inhibitory concentration (MIC) of the P. lactiflora ethanol extract against C. albicans cells increased 4-fold. In addition, synthesis of $(1,3)-{\beta}-{\small{D}}-glucan$ polymer was inhibited by 87% and 83% following treatment of C. albicans microsomes with the P. lactiflora ethanol extract at their $1{\times}MIC$ and $2{\times}MIC$, respectively. Second, the ethanol extract from P. lactiflora influenced the function of C. albicans cell membranes. C. albicans cells treated with the P. lactiflora ethanol extract formed red aggregates by staining with a membrane-impermeable dye, propidium iodide. Membrane depolarization manifested as increased fluorescence intensity by staining P. lactiflora-treated C. albicans cells with a membrane-potential marker, $DiBAC_4(3)$ ((bis-1,3-dibutylbarbituric acid) trimethine oxonol). Membrane permeability was assessed by crystal violet assay, and C. albicans cells treated with the P. lactiflora ethanol extract exhibited significant uptake of crystal violet in a concentration-dependent manner. The findings suggest that P. lactiflora ethanol extract is a viable and effective candidate for the development of new antifungal agents to treat Candida-associated diseases.

• The Journal of Korean Academy of Prosthodontics
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• v.37 no.3
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• pp.293-300
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• 1999

The purpose of this study was to evaluate the in vitro antifungal effect of several kinds of denture lining materials containing nystatin and silver-zeolite on Candida albicans. Three commercially available tissue conditioners (Soft-Liner, Coe-Comfort, Coe-Soft) and two direct denture relining materials (Tokuso Rebase, Durabase) were selected. In terms of the zone of inhibition and some basic physical properties, I could find the following results ; 1. Nystatin or silver-zeolite included in those relining materials had definite antifungal activities against the Candida albicans. 2. As times went on, both of the antifungal agents's activities decreased gradually. 3. Antifungal agents did not affect the relining materials' basic physical properties. 4 Direct chairside relining materials showed unfavorable dark discoloration with response to silver-zeolite.

• Korean Journal of Veterinary Research
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• v.57 no.2
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• pp.139-141
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• 2017

An 8-year-old castrated male Shih Tzu dog (weighing 7.0 kg) presented with anemia and lethargy. Initial diagnosis indicated immune-mediated hemolytic anemia. During therapy, a secondary urinary infection, probably due to the immune suppressive therapy, was diagnosed. Subsequent diagnostic tests, including urinalysis and urine culture, indicated candidal cystitis. Despite ketoconazole therapy for candidal cystitis, the dog died suddenly. A Candida albicans infection was confirmed upon postmortem evaluation. Prolonged immunosuppressive therapy might be the cause of this infection. This is the first case report describing a Candida albicans urinary tract infection accompanied by hemolytic anemia in a dog in Korea.

• Journal of Microbiology and Biotechnology
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• v.8 no.3
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• pp.291-294
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• 1998

Transfer of Candida albicans grown in Sabouraud medium to the RPMI medium induces the transition from a nonpathogenic yeast form to a pathogenic hyphal form. This transition was severely inhibited in a dose-dependent manner when deer antler extract was added to the RPMI medium in a nontoxic range (up to $500{\mu}g$). In that range, deer antler extract inhibited the hyphal transition and cell growth, whereas no effect was observed on the yeast growth. When hydrophobic or hydrophilic fractions were prepared by detergent-solubilization of deer antler extract, the hydrophobic fraction showed a large degree of inhibition of the hyphal growth in Candida albicans. Neither fraction affected the growth in the yeast form. The pattern of chitin localization in the culture of the yeast form grown in RPMI in the presence of deer antler extract was confirmed by calcofluor staining and this exhibited strongly the suppression of hyphal transition.

• Korean Journal of Pharmacognosy
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• v.40 no.4
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• pp.357-364
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• 2009

Phospholipids are crucially important in a cell membrane function and could thereby influence antibiotic susceptibility. In order to investigate the antifungal mechanism the total lipid was extracted from C. albicans treated with citronellol or thymol in concentration of their minimum inhibiting concentration and the changes in phospholipids composition were analyzed using ketoconazole as control. The cell growth and total lipid synthesis in cell walls of C. albicans were inhibited by treatment with citronellol. The levels of total lipids were decreased by 35.85% compared to the control. They also showed a significant decrease in the contents of phospholipid, phosphatidylcholine(PC), phosphatidyl ethanolamine(PE) and phosphatidylinositol(PI). As the result of GC assay for total fatty acid methyl esters of PC, PE and PI in C. albicans treated with citronellol, it was found that the major fatty acid composed of three phospholipid were palmitic acid, stearic acid and oleic acid. Moreover, the pattern of the fatty acid compositions of PC, PE and PI were changed by the oil. Based on the results, the anti-Candida mechanism of citronellol or thymol might be closely associated with disrupting the permeability barriers of the fungal cell wall composition or construction.

• KSBB Journal
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• v.32 no.2
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• pp.146-152
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• 2017

Vulvovaginal candidiasis (VVC) is one of the urogenital infections occurring in women worldwide. Candida albicans is generally observed among various types of microorganisms causing VVC. Antibiotic therapy is typical, and the use of Lactobacilli probiotics is to be recognized as a promising alternative. The aim of this study was to select vaginal lactobacilli with probiotic properties against C. albicans. In a previous study, we isolated 38 lactobacilli from vagina of Korean women and 20 isolates were shown to inhibit C. albicans. We further selected 10 isolates which were able to inhibit C. albicans less than $10^5CFU/mL$. Among these selected strains, Lactobacillus salivarius MG242 (identified by 16s rRNA sequencing) was finally selected based on its strong anti-candidal activity, acid/bile salt resistance and adhesion property. Indirect adhesion activity of MG242 measured by auto-aggregation assay showed more than 60% auto-aggregation after 5 h standing. Taken these results together, the selected strain MG242 may have potential for application in vagina health related products.

• Journal of Microbiology and Biotechnology
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• v.28 no.2
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• pp.181-189
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• 2018

Candida albicans is a major pathogenic fungus in humans, and meets at first the innate immune cells, such as macrophages, in its host. One important strategy of the host cell to kill C. albicans is to produce reactive oxygen species (ROS) by the macrophages. In response to ROS produced by the macrophages, C. albicans operates its defense mechanisms against them by expressing its oxidative stress response genes. Although there have been many research studies explaining the specific transcription factors and the expression of the oxidative stress genes in C. albicans, the regulation of the oxidative stress genes by chromatin structure is little known. Epigenetic regulation by the chromatin structure is very important for the regulation of eukaryotic gene expression, including the chromatin structure dynamics by histone modifications. Among various histone modifications, histone acetylation is reported for its direct relationship to the regulation of gene expression. Recent studies reported that histone acetyltransferases regulate genes to respond to the oxidative stress in C. albicans. In this review, we introduce all histone acetyltransferases that C. albicans contains and some papers that explain how histone acetyltransferases participate in the oxidative stress response in C. albicans.

• Journal of Microbiology and Biotechnology
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• v.26 no.3
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• pp.610-617
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• 2016

Candidiasis has posed a serious health risk to immunocompromised patients owing to the increase in resistant yeasts, and Candida albicans is the prominent pathogen of fungal infections. Therefore, there is a critical need for the discovery and characterization of novel antifungals to treat infections caused by C. albicans. In the present study, we report on the antifungal activity of the ethanol extract from Salvia miltiorrhiza against C. albicans and the possible mode of action against C. albicans. The increase in the membrane permeability was evidenced by changes in diphenylhexatriene binding and release of both 260-nm-absorbing intracellular materials and protein. In addition, inhibition of cell wall synthesis was demonstrated by the enhanced minimal inhibitory concentration in the presence of sorbitol and reduced (1,3)-β-D-glucan synthase activity. The above evidence supports the notion that S. miltiorrhiza has antifungal activity against C. albicans by the synergistic activity of targeting the cell membrane and cell wall. These findings indicate that S. miltiorrhiza displays effective activity against C. albicans in vitro and merits further investigation to treat C. albicans-associated infections.

• Journal of Microbiology and Biotechnology
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• v.30 no.12
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• pp.1827-1834
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• 2020

Candida albicans is a major fungal pathogen in humans. In our previous study, we reported that an ethanol extract from Aucklandia lappa weakens C. albicans cell wall by inhibiting synthesis or assembly of both (1,3)-β-D-glucan polymers and chitin. In the current study, we found that the extract is involved in permeabilization of C. albicans cell membranes. While uptake of ethidium bromide (EtBr) was 3.0% in control cells, it increased to 7.4% for 30 min in the presence of the A. lappa ethanol extract at its minimal inhibitory concentration (MIC), 0.78 mg/ml, compared to uptake by heat-killed cells. Besides, leakage of DNA and proteins was observed in A. lappa-treated C. albicans cells. The increased uptake of EtBr and leakage of cellular materials suggest that A. lappa ethanol extract induced functional changes in C. albicans cell membranes. Incorporation of diphenylhexatriene (DPH) into membranes in the A. lappa-treated C. albicans cells at its MIC decreased to 84.8%, after 60 min of incubation, compared with that of the controls, indicate that there was a change in membrane dynamics. Moreover, the anticandidal effect of the A. lappa ethanol extract was enhanced at a growth temperature of 40℃ compared to that at 35℃. The above data suggest that the antifungal activity of the A. lappa ethanol extract against C. albicans is associated with synergistic action of membrane permeabilization due to changes in membrane dynamics and cell wall damage caused by reduced formation of (1,3)-β-D-glucan and chitin.

• Journal of Dental Rehabilitation and Applied Science
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• v.30 no.3
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• pp.199-205
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• 2014

Purpose: The purpose of this study was to evaluate the transmission of candida in denture by dental polishing lathe. Materials and Methods: Maxillary complete dentures made from the same model were infected with Candida albicans. The infected dentures were polished by dental polishing lathe with sterile pumice and distilled water. And then sterile maxillary complete dentures were polished with same method. Polishing surface was wiped with a cotton swab and the sample was checked for Candida albicans. The polishing wheel at room temperature was checked for Candida albicans every 24 hours for 3 days. Results: A considerable number of Candida was found on the polished sterile dentures. And the Candida albicans in polishing wheel was detected at up to two days. Conclusion: An anti-infection measure is urgently needed when dental polishing lathe is used for denture polishing, because of the possibility of fungal infection.