Oral Candida Species Research Articles

Oral candida species in patients with periodontitis and diabetes mellitus

Oral candida species in patients with periodontitis and diabetes mellitus

Probiotic Lactobacillus reuteri has antifungal effects on oral Candida species in vitro

ABSTRACTBackground: An alternative approach for managing Candida infections in the oral cavity by modulating the oral microbiota with probiotic bacteria has been proposed.Objective: The aim was to investigate the antifungal potential of the probiotic bacterium Lactobacillus reuteri (DSM 17938 and ATCC PTA 5289) against six oral Candida species (C. albicans, C. glabrata, C. krusei, C. tropicalis, C. dubliniensis, and C. parapsilosis).Design: The lactobacilli were tested for their ability to co-aggregate with and inhibit the growth of the yeasts assessed by spectrophotometry and the agar overlay inhibition assay. Additionally, the pH was evaluated with microsensors, and the production of hydrogen peroxide (H2O2) by the lactobacilli was verified.Results: Both L. reuteri strains showed co-aggregation abilities with the yeasts. The lactobacilli almost completely inhibited the growth of C. albicans and C. parapsilosis, but did not affect C. krusei. Statistically significant differences in co-aggregation and growth inhibition capacities between the two L. reuteri strains were observed (p<0.001). The pH measurements suggested that C. krusei can resist the acids produced by the lactobacilli.Conclusions: L. reuteri exhibited antifungal properties against five of the six most common oral Candida species. Further, the results reconfirms that the probiotic capacity of L. reuteri is strain specific.

Antifungal activity of dual combination of hydroxychavicol with commercialized agents against oral Candida species.

Candida spp. is the most prevalent species causing systemic fungal infections. The effect of antifungal agents were screened in vitro and their synergism effect were determined between hydroxychavicol (HC) in association with commercialized antifungal drugs—amphotericin B (AMB), and 5-fluorocytosine (5-FC) alone and in combination against five different oral Candida spp. in their planktonic states at different ratio (1:1 v/v; 1:2 v/v and 2:1 v/v). In vitro susceptibilities of Candida spp. to HC and commercialized antifungal agents were investigated by broth microdilution method as described by Clinical and Laboratory Standards Institute M38-A2. The intensity of the interactions was evaluated by visual reading and spectrophotometric method in checkerboard microdiluton assay, and the nature of the interactions was assessed by fractional inhibitory concentration index. The minimum inhibitory concentration (MIC50) of HC, AMB and 5-FC alone against five different planktonic oral Candida spp. ranged from 240 to 120, 8 to 15, and 2 to 8 µg/mL respectively. Positive synergistic effect existed between HC and AMB at 1:1 ratio in all Candida spp. However, there was no synergy effect observed in the majority of Candida spp. for the combination of HC with 5-FC. The data of combination between HC with AMB may be useful in the treatment of systemic infections caused by oral Candida spp. instead of the combination of HC with 5-FC.

Profile of bacteria colonizing the exposed bone of patients with anti-osteoclastic drug-related osteonecrosis of the jaws.

Microbial etiology for anti-osteoclastic drug-related osteonecrosis of the jaw (ARONJ) was suggested. This study investigates any link between bacteria colonizing ARONJ sites and other oral cavity sites. Microbiota samples of 10 ARONJ patients were collected from the exposed bone, adjacent teeth, contralateral teeth, and tongue. DNA checkerboard hybridization was used for microbiota analysis with 43 genomic DNA probes prepared from human oral bacterial (38) and candida (5) species, using Socransky's bacterial complexes as a guide. The frequency and the mean proportion of each bacterial species were used. Eikenella corrodens, Streptococcus constellatus, and Fusobacterium nucleatum were dominant in the ARONJ sites and detected in most teeth samples. Staphylococcus aureus was also dominant in the ARONJ sites and tongue. Significant correlations were found between the mean proportions of bacterial species colonizing adjacent teeth, contralateral teeth, and tongue (p < 0.001, R(2) > 0.69). No significant correlation (p > 0.05, R(2) < 0.025) was found between bacteria colonizing ARONJ sites and other evaluated sites. Within the study limitations, it was concluded that the primary sources of microorganisms colonizing ARONJ sites could be other sites such as teeth and tongue. The microbial profile of the necrotic bone is predominantly colonized with bacteria from Socransky's green and orange complexes, as well as with species associated with bone infections.

In vitro inhibitory activity of probiotic products against oral Candida species.

To evaluate the inhibitory activity of probiotics against oral Candida species. Four commercial probiotic products were screened. Bacillus subtilis R0179 was found to have a significant antifungal effect. Bacillus subtilis-Candida interactions were evaluated using disc diffusion tests, confocal laser scanning microscopy, scanning electron microscopy and interaction with engineered human oral mucosa tissue. Bacillus subtilis exhibited clear zones of inhibition for Candida albicans and Candida parapsilosis but not for Candida krusei. A remarkable reduction in the number of Candida cells and abundant Candida cell death were visualized with confocal laser scanning microscopy. Shrinkage and deformation of Candida cells was observed using scanning electron microscopy. Culture of C.albicans on engineered human oral mucosa tissues resulted in the presence of a large number of yeast cells on the tissue surface and the development of large-scale tissue damage. However, comparatively fewer Candida cells were observed on B.subtilis-treated tissues. We also use ultra performance liquid chromatography/time of flight mass spectrometry (UPLC/TOF MS) to explore the preliminary antifungal mechanism of B.subtilis R0179 and to detect that whether it can secrete an antifungal agent, Iturin A. Bacillus subtilis R0179 exhibits a significant inhibitory effect on the growth of Candida species. Bacillus subtilis has the potential to be used in the prevention or treatment of oral candidiasis.

In vitro Impact of Limited Exposure to Subtherapeutic Concentrations of Chlorhexidine Gluconate on the Adhesion-Associated Attributes of Oral Candida Species

Objective:Candida albicans and its non-albicans counterparts, such as C. tropicalis, C. krusei, C. glabrata and C. dubliniensis, are the major etiological agents of oral candidosis. Their adherence to buccal epithelial cells (BEC), denture acrylic surfaces (DAS) and cell surface hydrophobicity (CSH) are attributes associated with yeast colonization and infection. Chlorhexidine gluconate (CG) is a widely used antiseptic in dentistry. When administered, the diluent effect of saliva and the cleansing effect of the oral musculature reduce its bioavailability, compromising its efficacy. Hence, intraorally, Candida undergoes a transient exposure to high CG concentrations, and thereafter it is likely to be subtherapeutic. Therefore, the impact of CG on adhesion to BEC, DAS and CSH of different oral Candida species was investigated following brief exposure to three subtherapeutic concentrations of CG. Materials and Methods: Ten oral isolates of each of the above five Candida species obtained in Kuwait from oral rinse samples were exposed to 0.00125, 0.0025 and 0.005% CG for 30 min. Subsequently, the yeast adhesion to BEC, DAS and CSH was determined. The data were analyzed using ANOVA Dunnett's t tests. Results: Exposure to the lowest dilution (0.00125%) of CG did not elicit a noteworthy collective suppression on all three adhesion traits evaluated. Exposure to 0.0025% CG curtailed the adhesion to BEC, DAS and CSH of Candida species by 50.89, 40.79 and 24.58%, respectively (p < 0.001). Exposure to the highest concentration (0.005%) of CG reduced the adhesion to BEC, DAS and CSH of Candida species by 64.68, 54.59 and 50%, respectively (p < 0.001). Conclusions: Brief exposure to subtherapeutic concentrations of CG suppressed the adhesion to BEC, DAS and CSH of oral Candida species, indicating probable pharmacodynamics that may potentiate its antiseptic properties.

Candida/Candida biofilms. First description of dual-species Candida albicans/C. rugosa biofilm

Denture liners have physical properties that favour plaque accumulation and colonization by Candida species, irritating oral tissues and causing denture stomatitis. To isolate and determine the incidence of oral Candida species in dental prostheses, oral swabs were collected from the dental prostheses of 66 patients. All the strains were screened for their ability to form biofilms; both monospecies and dual-species combinations were tested. Candida albicans (63 %) was the most frequently isolated microorganism; Candida tropicalis (14 %), Candida glabrata (13 %), Candida rugosa (5 %), Candida parapsilosis (3 %), and Candida krusei (2 %) were also detected. The XTT assay showed that C. albicans SC5314 possessed a biofilm-forming ability significantly higher (p < 0.001) than non-albicans Candida strains, after 6 h 37 °C. The total C. albicans CFU from a dual-species biofilm was less than the total CFU of a monospecies C. albicans biofilm. In contrast to the profuse hyphae verified in monospecies C. albicans biofilms, micrographies showed that the C. albicans/non-albicans Candida biofilms consisted of sparse yeast forms and profuse budding yeast cells that generated a network. These results suggested that C. albicans and the tested Candida species could co-exist in biofilms displaying apparent antagonism. The study provide the first description of C. albicans/C. rugosa mixed biofilm.

Antifungal effect of green tea extracts on oral Candida species: An in vitro study

Background: Candida is one of the commensals housing the normal oral flora. Oral candidiasis is a common opportunistic infection caused by Candida species (Candida albicans being the most common one). Green tea is well-known for its various health benefits, and the literature reveals ongoing studies on the action mechanisms of green tea extract, in vitro and in vivo. Aims and Objectives: The present study was undertaken to assess antifungal effect of green tea extracts; if proven, could it be used in future as an adjunctive treatment modality for treating candidiasis. Materials and Methods: About 15 healthy volunteers with coated tongue were included for the study. Oral sample, from dorsum of the tongue was collected by commercially available pre-sterilized swabs. The material was inoculated into Sabouraud’s Dextrose Agar; confirmed for the presence of Candida species. The sensitivity test was carried out on a lawn culture with 25% and 50% green tea extracts at 24 h and 48 h intervals. The antifungal activity was assessed. Distilled water was used as a control. Student’s paired t-test was used to assess the difference in inhibition effect between 25% and 50% of green tea extract solution. Results: Statistically significant increase in the zone of inhibition was noticed at both 25% and 50% concentration of green tea extracts when compared to control group, which did not show any zone of inhibition. Conclusion: Having shown antifungal effects, the green tea extracts may be considered in future as a therapeutic adjunct.

Oral Candida colonization in HIV-infected patients in Londrina-PR, Brazil: antifungal susceptibility and virulence factors.

Host colonization by Candida species is an important predisposing factor to candidiasis, which seems to be more frequent in human immunodeficiency virus (HIV)-infected patients. Knowledge about the distribution, antifungal susceptibility, and virulence of oral Candida isolates is important for effective management of candidiasis. Oral rinses were collected from 242 HIV-infected patients without clinical evidence of candidiasis seen at the AIDS referral center in Londrina, Brazil. Species were identified by standard phenotypic and molecular methods, and characterized in vitro according to antifungal susceptibility, cell surface hydrophobicity, biofilm formation, and enzyme activities. Oral Candida colonization was detected in 50.4% of patients and combined use of antiretroviral therapy and protease inhibitor had a protective effect against colonization. Candida albicans (75.2%) was the most prevalent species. A high proportion of Candida spp. (39.9%) showed decreased susceptibility to fluconazole. Five isolates were resistant to nystatin. Protease and phospholipase activities were detected in 100% and 36.8% of isolates, respectively. Most isolates displayed a hydrophobic property that was associated with biofilm formation ability. A significant number of oral Candida species exhibiting decreased susceptibility to fluconazole were isolated from colonized HIV-infected individuals. Furthermore, all isolates expressed potential virulence attributes in vitro. Given the high incidence and severity of fungal infections in HIV-infected individuals, the results of this study reinforce the importance of antifungal susceptibility testing, which contributes to therapeutic strategies and highlights the need for continuous surveillance of Candida colonization in this population.

Triphala in Prevention of Dental Caries and as an Antimicrobial in Oral Cavity- A Review

Dental caries is a widely prevalent infectious disease afflicting the humans worldwide. Each year oral infections such as dental caries, periodontal diseases and oral candidiasis significantly adds to the economic burden of the world. Though there are standard management techniques for these diseases; they do have side effects and are not cost effective. Ayurveda is a traditional Indian system of medicine that is being practiced in the Indian peninsula since ages. Among the various herbal medicines in ayurveda, triphala occupies a royal position due to its wide beneficial systemic actions. Triphala is a mixture of fruits of Terminalia bellirica, Terminalia chebula and Emblica officinalis. The antimicrobial actions of triphala are well documented in the literature. However availability of review articles regarding triphala as an antimicrobial against oral infections is limited. Need was felt to review this aspect of triphala. The present article reviews the use of triphala and its constituents in the prevention and control of dental caries and other common oral infections. Thorough review of the literature indicated that triphala can be effectively used to manage dental caries, gingival and periodontal diseases. Further it can also be utilized as a root canal irrigant and against oral candida species.

Synergistic effects of tea catechin epigallocatechin gallate and antimycotics against oral Candida species

ObjectiveEpigallocatechin gallate (EGCG), the major antimicrobial tea polyphenol, has been reported to inhibit the growth of Candida albicans planktonic cells and enhance the antifungal activity of antimycotics. We hypothesised that synergism exists between EGCG and conventional antimycotics against biofilms of Candida species. DesignThe minimal inhibitory concentrations (MIC) of EGCG, miconazole, fluconazole and amphotericin B against planktonic cells and the sessile MIC (SMIC) against biofilms of Candida albicans, Candida parapsilosis, Candida tropicalis, Candida glabrata, Candida kefyr and Candida krusei were determined by a microdilution method. For assessment of biofilm metabolic activity, the 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) assay was used. The interactions between EGCG and antimycotics were evaluated by checkerboard microdilution assay and determined by fractional inhibitory concentration index (FIC). ResultsSynergism was observed between EGCG and miconazole, fluconazole or amphotericin B against most test planktonic and biofilm cells of Candida species (FIC≤0.5). All biofilm cells were significantly more resistant to EGCG and antimycotics (20–3200 times higher) compared with their planktonic counterparts. ConclusionsWe conclude that EGCG enhances the antifungal effects of miconazole, fluconazole and amphotericin B. Combined treatment with EGCG may lower the dosages of antimycotics, thus preventing adverse effects and the emergence of drug-resistant oral Candida species.

Relationship between acetaldehyde concentration in mouth air and tongue coating volume.

Objective Acetaldehyde is the first metabolite of ethanol and is produced in the epithelium by mucosal ALDH, while higher levels are derived from microbial oxidation of ethanol by oral microflora such as Candida species. However, it is uncertain whether acetaldehyde concentration in human breath is related to oral condition or local production of acetaldehyde by oral microflora. The aim of this pilot study was to investigate the relationship between physiological acetaldehyde concentration and oral condition in healthy volunteers.Material and Methods Sixty-five volunteers (51 males and 14 females, aged from 20 to 87 years old) participated in the present study. Acetaldehyde concentration in mouth air was measured using a portable monitor. Oral examination, detection of oral Candida species and assessment of alcohol sensitivity were performed.Results Acetaldehyde concentration [median (25%, 75%)] in mouth air was 170.7 (73.5, 306.3) ppb. Acetaldehyde concentration in participants with a tongue coating status score of 3 was significantly higher than in those with a score of 1 (p<0.017). After removing tongue coating, acetaldehyde concentration decreased significantly (p<0.05). Acetaldehyde concentration was not correlated with other clinical parameters, presence of Candida species, smoking status or alcohol sensitivity.Conclusion Physiological acetaldehyde concentration in mouth air was associated with tongue coating volume.

English

The objective of this study was to evaluate the antifungal activity of the aqueous extract of the leaves of the &quot;verbena&quot; (gerv&atilde;o roxo) Stachytarpheta cayennensis, (Rich.) Vahl. (Verbenaceae), by determining the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) on different species and strains of the genus Candida. In this study, the species Candida albicans, Candida tropicalis, Candida glabrata, Candida stellatoidea, Candida dubliniensis and Candida krusei were included. Four strains of C. albicans and three of C. tropicalis were used, while for the other species only one strain was tested. These yeasts were used in this study because of their importance and frequency in the oral cavity. The yeasts were subjected to treatments with concentrations of the aqueous extract ranging from 0.09 to 25 mg mL-1. The results indicated, however, that concentrations of less than 12.5 mg mL-1 were insufficient to show a fungistatic or fungicidal effect. The concentration of 12.5 mg mL-1 &nbsp;showed a fungistatic effect on most tested strains and species, C. albicans C&alpha;FB-12 and ATCC-44858; C. tropicalis CTFB-22 and CTFB29. The fungicidal effect (MFC) was observed only on the species C. krusei for the concentration of 12.5 mg mL-1. Based on the employed methodology, it is concluded that the aqueous extract of S. cayennensis showed an antifungal, mainly fungistatic, effect on oral Candida species. &nbsp; Key words: Yeasts, candidiasis, metabolites, Stachytarpheta cayennensis.

Antifungal Resistance Patterns, Virulence Attributes and Spectrum of Oral Candida Species in Patients with Periodontal Disease

Aims: To observe the antifungal resistance pattern, virulence attributes and spectrum of Candida species in oral cavities of patients with periodontal diseases and healthy individuals. Study Design: A total number of 52 patients with periodontal disease and 100 healthy subjects were included in the study. Place and Duration: The study was carried out in the Apex Regional STD Teaching, Training and Research Centre, VMMC and Safdarjang Hospital and Department of Biosciences, Jamia Millia Islamia, New Delhi. Duration of the study was from December 2011 to June 2013. Methodology: Oral swabs were collected from the patients and control group. The specimens Original Research Article Kumar et al.; BMRJ, 5(1): 68-75, 2015; Article no. BMRJ.2015.008 69 were cultured for Candida and the species identified, according to standard protocols. Antifungal susceptibility testing and virulence tests were performed. Results: Out of 52 patients screened 11 yielded (21%) different Candida species, with Candida albicans (83%) being the commonest and non Candida albicans Candida (NCAC) species accounting for 17 %. Among 100 healthy controls, 23 were colonized by various Candida species, with Candida albicans again as the predominant species. A significant difference (P =.002) was observed in the secretion of proteinase enzyme between the isolates from cases and controls. However, in the distribution of Candida species, antifungal resistance patterns, phospholipase secretion and biofilm formation there was no such significant difference. Conclusion: Our results reveal that there is no significant difference in the distribution of Candida species among healthy subjects and patients with periodontal diseases. Antifungal resistance patterns and expression of some of the important virulence attributes also revealed no differences between the isolates from patients and control populations.

Inhibitory activity in vitro of probiotic lactobacilli against oral Candida under different fermentation conditions.

Clinical studies have shown that probiotics positively affect oral health by decreasing gum bleeding and/or reducing salivary counts of certain oral pathogens. Our aim was to investigate the inhibitory effect of six probiotic lactobacilli against opportunistic oral Candida species. Sugar utilisation by both lactobacilli and Candida was also assessed. Agar overlay assay was utilised to study growth inhibition of Candida albicans, Candida glabrata and Candida krusei by Lactobacillus rhamnosus GG, Lactobacillus casei Shirota, Lactobacillus reuteri SD2112, Lactobacillus brevis CD2, Lactobacillus bulgaricus LB86 and L. bulgaricus LB Lact. The inhibitory effect was measured at pH 5.5, 6.4, and 7.2, respectively, and in the presence of five different carbohydrates in growth medium (glucose, fructose, lactose, sucrose, and sorbitol). Growth and final pH values were measured at two-hour time points to 24 h. L. rhamnosus GG showed the strongest inhibitory activity in fructose and glucose medium against C. albicans, followed by L. casei Shirota, L. reuteri SD2112 and L. brevis CD2. None of the lactobacilli tested affected the growth of C. krusei. Only L. rhamnosus GG produced slight inhibitory effect on C. glabrata. The lower pH values led to larger inhibition zones. Sugar fermentation profiles varied between the strains. L. casei Shirota grew in the presence of all sugars tested, whereas L. brevis CD2 could utilise only glucose and fructose. All Candida species metabolised the available sugars but the most rapid growth was observed with C. glabrata. The results suggest that commercially available probiotics differ in their inhibitory activity and carbohydrate utilisation; the above properties are modified by different pH values and sugars with more pronounced inhibition at lower pH.

보철물 장착 환자의 구강 칸디다균 분포

본 연구는 보철물 장착 환자의 구강 내 C. albicans 분포에 대한 연구로 구강 Candida 감염증의 주 원인균인 C. albicans의 분포를 측정한 후 감염 위험정도의 분석을 통해 보철물 장착 환자들에게 구강건강관리의 중요성에 대한 자료로 제공하고자 연구대상자의 성별, 흡연 및 음주유무, 구강 내 보철물 종류 및 장착 기간, 1일 칫솔질 횟수에 따른 C. albicans 집락 정도를 조사하였다. 연구대상자들 중 11.6%에서 감염 1단계 이상의 분포를 보여 구강 Candida 감염 가능성을 확인하였다. 또한 타액 채취 부위별 C. albicans 분포를 분석한 결과 상악보다 하악의 설면에서, 입천장보다 혀 등이 상대적으로 높은 단계의 분포를 보였다. 성별, 흡연 및 음주유무에 따른 C. albicans 분포는 여자보다 남자가, 흡연을 하는 경우보다 흡연을 하지 않는 경우가, 음주를 하지 않는 경우보다 음주를 하는 경우에 구강 Candida 감염 단계 평균 수치가 높게 나타났다. C. albicans의 단계별 분포는 구강 Candida 감염 3단계의 분포가 여자는 관찰되지 않았지만 남자는 1.4%의 분포가 관찰되었으며, 구강 Candida 감염 2단계 이상의 분포가 흡연 및 음주를 하는 경우에는 관찰되지 않았지만 하지 않는 경우에는 각각 3.3%, 3.6%의 분포가 관찰되었다. 구강 내 보철물 중 가철성 교정장치보다 의치 혹은 임플란트를 장착한 경우 C. albicans의 분포에 더 영향을 미치고 있으며, 보철물을 1년 이상 장착한 경우에 기간이 길어질수록 구강 Candida 감염 1단계 이상의 분포가 점점 높아졌다. 단, 7~9년 장착한 경우에는 100.0%의 0단계의 분포를 보였다. 1일 칫솔질 횟수에 따른 구강 Candida 감염 단계 평균 수치를 통해 구강위생관리와 C. albicans의 분포의 상관관계를 확인하고자 하였으나 칫솔질 횟수는 직접적으로 작용하지 않는 것으로 보였다. 이상의 결과로 볼 때 보철물 장착 환자의 성별, 구강 내 부위, 보철물 종류, 보철물 장착 기간이 구강 내 C. albicans의 분포에 영향을 미치고 있는 것으로 나타났다. 향후 관련된 여러 요인들을 모두 추가, 보완하거나 다각적으로 검토하여 심도 있는 연구를 통해 구강건강을 유지 및 증진시킬 수 있는 자료를 확보하는 것이 필요하다고 생각된다. Of the many pathogenic Candida species, Candida albicans is the main fungal pathogen of humans. The oral environmental factors considered in the Candida albicans colony forming unit test contain both host and microbial factors associated with candidiasis. In particular, Candida biofilms can develop on surfaces of prosthesis. The purpose of this study was to investigate the distribution of oral Candida species between the type of prosthesis and the situation of oral environment in patient with prosthetic appliance. The patients were 30 elderly subjects with different types of prosthesis, 7 who wore denture, 12 who wore implant and 15 who wore removable orthodontic appliance. We used Candida albicans colony forming unit test using saliva to exam the distribution of Candida albicans related with 5 oral environmental factors, gender, smoking or nonsmoking, alcohol/nonalcohol consumption, the type of prosthetic appliance and its treatment duration as well as tooth brushing frequency per day. In conclusion, for the patient's gender, site in the oral cavity and the type of prosthetic appliance and its treatment duration was associated with an increase in the distribution of Candida albicans in saliva. The distribution of Candida albicans within the oral cavity performs to be modulated to varying extents by oral environmental factors and, further investigations are required to elucidate these complex interactions.

Isolation of Candida Species from the Oral Cavity and Fingertips of Complete and Partial Dentures Wearers

Purpose: Removable denture wearers commonly use their fingers to take out their prostheses from their mouths and oral Candida, if present, may colonize their fingers and constitute a source of contamination. The aim of this study was to find out the difference in oral and fingertips Candida isolation before and after wearing the prostheses, and to investigate the association between oral and fingertip Candida colonization. Methods: Fifty healthy subjects, wearing removable complete or partial dentures for the first time were included. Oral Candida species were isolated using the concentrated oral rinse technique while fingertips Candida were isolated by pressing the fingers of both hands on a plate of Sabouraud’s dextrose agar. Candida species were identified using the VITEK 2® yeast identification system. Three samples were taken from each subject; one at the insertion of the prosthesis, after one month and after two months of the insertion visit. Results: The prevalence and density of oral Candida colonization were both higher after one and two months of the insertion of removable complete and partial dentures but the difference was not statistically significant (P > 0.05). No statistically significant difference was also found between the complete denture wearers (CDW’s) and partial denture wearers (PDW’s) regarding the mean candidal count (P > 0.05). Oral and fingertips Candida species presence among the same CDWs or PDWs at the initial, first and second visits was statistically insignificant.

Oral Candida carriage and immune status in Thai human immunodeficiency virus-infected individuals

Oral candidiasis is a common opportunistic infection among human immunodeficiency virus (HIV)-infected individuals, with growing concerns about the emergence of non-albicans species with resistance to antifungal agents. This cross-sectional study determined the prevalence of oral Candida species in Thai HIV-infected adults and factors affecting their colonization. Candida species were identified from oral rinse samples of 60 HIV-infected participants of the MTCT-Plus initiative and 49 healthy controls by culture-based and molecular assays. The prevalence of oral Candida carriage was similar in HIV-infected patients (56.6 %) and in controls (55.1 %, P = 0.87). Candida albicans was the most predominant species in both groups (94.1 % of Candida carriers in HIV, 88.9 % in control). Interestingly, Candida dubliniensis was the second most common species in controls (29.6 %) and the third in HIV-infected patients (11.8 %, P = 0.08). Multivariate analysis showed that, amongst HIV-infected individuals, CD4 count <200 cells mm(-3) was associated with increased prevalence of oral carriage of both C. albicans (P = 0.03) and non-albicans species (P = 0.03). Moreover, patients with tuberculosis infection had a higher prevalence of the non-albicans species than those without (P = 0.03). Intriguingly, contraceptive use was also associated positively with non-albicans and multi-species carriage (P = 0.04 for both). However, use of antiretroviral drugs protected the patients from Candida carriage (P = 0.03), especially from C. albicans (P = 0.02). In conclusion, while HIV-infected individuals had a similar prevalence of oral Candida carriage to that of the control group, host immune status, tuberculosis infection, and contraceptive use may influence oral colonization of Candida, especially of the non-albicans species.

Volatile compounds of Salvadora persica inhibit the growth of oral Candida species

ObjectiveThe antibacterial effect of Salvadora persica has been demonstrated both in vitro and in vivo. However, data on its possible antifungal effect is scarce. Therefore, the aim of the present study was to investigate the antifungal effect of solid or pulverized S. persica on clinically important oral Candida species in vitro. DesignThe antifungal activity of S. persica was examined against reference strains and clinical isolates of oral Candida species by two different methods. In an agar diffusion test, solid as well as pulverized pieces of S. persica were tested. Mounting the S. persica test specimens inside the lid tested growth inhibition by volatile compounds. ResultsS. persica exhibited antifungal activity against all Candida species tested. In particular, the volatile compounds of solid test specimens demonstrated strong growth inhibition, whereas pulverized S. persica revealed no antifungal activity. Parameters such as storage and incubation time as well as the diameter of the sticks influenced the growth inhibition. ConclusionsVolatile compounds of S. persica have antifungal activity against oral Candida species. Storage time after harvesting may play an important role for the strength of this antifungal activity.

Antifungal susceptibility and growth inhibitory response of oral Candida species to Brucea javanica Linn. extract

BackgroundCandida species have been associated with the emergence of resistant strains towards selected antifungal agents. Plant products have been used traditionally as alternative medicine to ease candidal infections. The present study was undertaken to investigate the antifungal susceptibility patterns and growth inhibiting effect of Brucea javanica seeds extract against Candida species.MethodsA total of seven Candida strains that includes Candida albicans ATCC14053, Candida dubliniensis ATCCMYA-2975, Candida glabrata ATCC90030, Candida krusei ATCC14243, Candida lusitaniae ATCC64125, Candida parapsilosis ATCC22019 and Candida tropicalis ATCC13803 were used in this study. The antifungal activity, minimum inhibitory concentration and minimum fungicidal concentration of B. javanica extract were evaluated. Each strain was cultured in Yeast Peptone Dextrose broth under four different growth environments; (i) in the absence and presence of B. javanica extract at respective concentrations of (ii) 1 mg/ml (iii) 3 mg/ml and (iv) 6 mg/ml. The growth inhibitory responses of the candidal cells were determined based on changes in the specific-growth rates (μ) and doubling time (g). The values in the presence of extract were computed as percentage in the optical density relative to that of the total cells suspension in the absence of extract.ResultsB. javanica seeds extract exhibited antifungal properties. C. tropicalis showed the highest growth rate; 0.319 ± 0.002 h-1, while others were in the range of 0.141 ± 0.001 to 0.265 ± 0.005 h-1. In the presence of extract, the lag and log phases were extended and deviated the μ- and g-values. B. javanica extract had significantly reduced the μ-values of C. dubliniensis, C. krusei and C. parapsilosis at more than 80% (ρ < 0.05), while others were reduced within the range of 2.28% to 57.05%. The g-values of most candidal strains were extended and significantly reduced (ρ < 0.05) in relative to the untreated. The candidal population was reduced from an average of 10 x 106 to 6 x 106 CFU/ml.ConclusionsB. javanica extract exhibited in vitro antifungal activity against seven oral Candida species. The fungistatic and growth inhibiting effects of B. javanica extract have shown that it has potential to be considered as a promising candidate for the development of antifungal agent in oral health products.