Antifungal Activity of Sodium Bicarbonate Against Fungal Agents Causing Superficial Infections

Bathing in Atopic Dermatitis in Pediatric Age: Why, How and When

Atopic dermatitis is a chronic inflammatory skin disease. The treatment plays an important role in influencing the patients' quality of life. The basic management consists of appropriate skin cleansing, including bathing and eventually using bathing additives. Recommendations regarding frequency and duration of bathing, water temperature and usefulness of bathing additives are widely different, often leading to confusion among patients. This review aims to give insights into the best bathing practices and the use of bathing additives in atopic dermatitis in children. Several bathing additives, including bleach baths, commercial baby cleansers, bath baby oils and bath salt, appear to be promising adjunctive therapies for atopic dermatitis due to their anti-inflammatory, anti-bacterial, anti-pruritus and skin barrier repair properties through different mechanisms of action. However, their efficacy and safety are not fully understood in some cases. The usefulness of other bath additives, such as acidic and more natural substances (green tea extracts, pine tar, sodium bicarbonate), is still under investigation. Further studies are needed to determine their optimal use to achieve clinical benefit safely.

Did you choose appropriate mouthwash for managing chemoradiotherapy-induced oral mucositis? The therapeutic effect compared by a Bayesian network meta-analysis

Background

Oral mucositis (OM) is one of the most common adverse effects of radiotherapy and chemotherapy. It greatly affects the patients' quality of life and hinders cancer treatment implementation. Treating OM with mouthwash is a widely used strategy that can effectively relieve symptoms and promote healing. However, the wide mouthwash selection confuses clinicians. This Bayesian network meta-analysis aimed to compare the effects of various mouthwash types used to treat OM and provide high-level evidence-based recommendations for OM treatment.

Methods

Database search included PubMed, Embase, Cochrane Library, and Web of Science from inception to April 21, 2022. The primary outcome was OM score improvement following the World Health Organization grades. The randomized controlled trial (RCT) bias risk assessment tool provided in the Cochrane Handbook assessed the studies' risk of bias. We performed pairwise and Bayesian network meta-analysis with random effects following the PRISMA guideline.

Results

The study included 13 RCTs with 570 patients. Pairwise comparisons showed that povidone-iodine was more effective than chlorhexidine (weighted mean difference [WMD], -2.64; 95% confidence interval [CI], -2.72 to -2.56) but inferior to granulocyte-macrophage colony-stimulating factor (GM-CSF; WMD, 0.20; 95% CI, 0.06-0.34) after one week of mouthwash treatment. Vitamin E (WMD, -0.94; 95% CI, -1.03 to -0.85), natural drugs (WMD, -0.93; 95% CI, -1.46 to -0.40), and phenytoin (WMD, -0.38; 95% CI, -0.59 to -0.17) exhibited better therapeutic effects than a placebo after three weeks of treatment. Bayesian network meta-analysis showed that povidone-iodine was superior to chlorhexidine in treating OM (WMD, 2.63; 95% CI, 0.20-5.01). Other mouthwashes showed no significant differences. Rank probability indicated that the best OM therapeutic mouthwashes were GM-CSF (54%), vitamin E (24%), and natural drugs (43%) after one, two, and three weeks of treatment, respectively.

Conclusion

GM-CSF was the most effective mouthwash type for OM treatment. When considering the cost and effectiveness, povidone-iodine and sodium bicarbonate might be the most advantageous. Furthermore, natural drugs have the same potential in treating OM. Safety and acceptability are their most outstanding characteristic.

New Strain of Cyphellophora olivacea Exhibits Striking Tolerance to Sodium Bicarbonate

The cyanobacterium strain Synechococcus cedrorum SAG 88.79 stock culture has fungal contamination stated by the Sammlung von Algenkulturen der Universität Göttingen itself. In this recent work, this particular fungal strain was isolated, identified, and morphologically characterised. The fungal strain AGSC12 belongs to the species Cyphellophora olivacea, with respect to the sequence similarity, phylogeny, and morphology of the strain. Colony morphology and growth capability were examined on SMA, EMMA, PDA, MEA, YEA, and YPA plates. Growth of the colonies was the most successful on YPA plates, followed by PDA and MEA containing plates. Surprisingly, the AGSC12 strain showed extreme tolerance to NaHCO3, albeit it, is is considered a general fungistatic compound. Moreover, positive association between the AGSC12 and SAG 88.79 strains was revealed, as the SAG 88.79 strain always attained higher cell density in co-cultures with the fungus than in mono-cultures. Besides, a taxonomic note on the SAG 88.79 strain itself was also stated.

Genome-Wide Identification of Cellular Pathways and Key Genes That Respond to Sodium Bicarbonate Stress in Saccharomyces cerevisiae

Sodium bicarbonate (NaHCO₃) is an important inorganic salt. It is not only widely used in industrial production and daily life, but is also the main stress in alkaline saline soil. NaHCO₃ has a strong ability to inhibit the growth of fungi in both natural environment and daily application. However, the mechanism by which fungi respond to NaHCO₃ stress is not fully understood. To further clarify the toxic mechanisms of NaHCO₃ stress and identify the specific cellular genes and pathways involved in NaHCO₃ resistance, we performed genome-wide screening with NaHCO₃ using a Saccharomyces cerevisiae deletion mutant library. A total of 33 deletion mutants with NaHCO₃ sensitivity were identified. Compared with wild-type strains, these mutants had significant growth defects in the medium containing NaHCO₃. Bioinformatics analysis found that the corresponding genes of these mutants are mainly enriched in the cell cycle, mitophagy, cell wall integrity, and signaling pathways. Further study using transcriptomic analysis showed that 309 upregulated and 233 downregulated genes were only responded to NaHCO₃ stress, when compared with yeast transcriptomic data under alkaline and saline stress. Upregulated genes were mainly concentrated in amino acid metabolism, steroid biosynthesis, and cell wall, while downregulated genes were enriched in various cellular metabolisms. In summary, we have identified the cellular pathways and key genes that respond to NaHCO₃ stress in the whole genome, providing resource and direction for understanding NaHCO₃ toxicity and cellular resistance mechanisms.

Chemical or Genetic Alteration of Proton Motive Force Results in Loss of Virulence of Burkholderia glumae, the Cause of Rice Bacterial Panicle Blight

Rice is an important source of food for more than half of the world's population. Bacterial panicle blight (BPB) is a disease of rice characterized by grain discoloration or sheath rot caused mainly by Burkholderia glumae. B. glumae synthesizes toxoflavin, an essential virulence factor that is required for symptoms of the disease. The products of the tox operons, ToxABCDE and ToxFGHI, are responsible for the synthesis and the proton motive force (PMF)-dependent secretion of toxoflavin, respectively. The DedA family is a highly conserved membrane protein family found in most bacterial genomes that likely function as membrane transporters. Our previous work has demonstrated that absence of certain DedA family members results in pleiotropic effects, impacting multiple pathways that are energized by PMF. We have demonstrated that a member of the DedA family from Burkholderia thailandensis, named DbcA, is required for the extreme polymyxin resistance observed in this organism. B. glumae encodes a homolog of DbcA with 73% amino acid identity to Burkholderia thailandensis DbcA. Here, we created and characterized a B. glumae ΔdbcA strain. In addition to polymyxin sensitivity, the B. glumae ΔdbcA strain is compromised for virulence in several BPB infection models and secretes only low amounts of toxoflavin (∼15% of wild-type levels). Changes in membrane potential in the B. glumae ΔdbcA strain were reproduced in the wild-type strain by the addition of subinhibitory concentrations of sodium bicarbonate, previously demonstrated to cause disruption of PMF. Sodium bicarbonate inhibited B. glumae virulence in rice, suggesting a possible non-toxic chemical intervention for bacterial panicle blight. IMPORTANCE Bacterial panicle blight (BPB) is a disease of rice characterized by grain discoloration or sheath rot caused mainly by Burkholderia glumae. The DedA family is a highly conserved membrane protein family found in most bacterial genomes that likely function as membrane transporters. Here, we constructed a B. glumae mutant with a deletion in a DedA family member named dbcA and report a loss of virulence in models of BPB. Physiological analysis of the mutant shows that the proton motive force is disrupted, leading to reduction of secretion of the essential virulence factor toxoflavin. The mutant phenotypes are reproduced in the virulent wild-type strain without an effect on growth using sodium bicarbonate, a nontoxic buffer that has been reported to disrupt the PMF. The results presented here suggest that bicarbonate may be an effective antivirulence agent capable of controlling BPB without imposing an undue burden on the environment.

Antibacterial Effects of Bicarbonate in Media Modified to Mimic Cystic Fibrosis Sputum

Cystic fibrosis (CF) is a hereditary disease caused by mutations in the gene encoding an epithelial anion channel. In CF, Cl⁻ and HCO₃⁻ hyposecretion, together with mucin hypersecretion, leads to airway dehydration and production of viscous mucus. This habitat is ideal for colonization by pathogenic bacteria. We have recently demonstrated that HCO₃⁻ inhibits the growth and biofilm formation of Pseudomonas aeruginosa and Staphylococcus aureus when tested in laboratory culture media. Using the same bacteria our aim was to investigate the effects of HCO₃⁻ in artificial sputum medium (ASM), whose composition resembles CF mucus. Control ASM containing no NaHCO₃ was incubated in ambient air (pH 7.4 or 8.0). ASM containing NaHCO₃ (25 and 100 mM) was incubated in 5% CO₂ (pH 7.4 and 8.0, respectively). Viable P. aeruginosa and S. aureus cells were counted by colony-forming unit assay and flow cytometry after 6 h and 17 h of incubation. Biofilm formation was assessed after 48 h. The data show that HCO₃⁻ significantly decreased viable cell counts and biofilm formation in a concentration-dependent manner. These effects were due neither to extracellular alkalinization nor to altered osmolarity. These results show that HCO₃⁻ exerts direct antibacterial and antibiofilm effects on prevalent CF bacteria.

Sodium New Houttuyfonate Inhibits Candida albicans Biofilm Formation by Inhibiting the Ras1-cAMP-Efg1 Pathway Revealed by RNA-seq

Here, we aim to investigate the antifungal effect and mechanism of action of sodium new houttuyfonate (SNH) against Candida albicans. Microdilution analysis results showed that SNH possesses potent inhibitory activity against C. albicans SC5314, with a MIC₈₀ of 256 μg/mL. Furthermore, we found that SNH can effectively inhibit the initial adhesion of C. albicans. Inverted microscopy, crystal violet staining, scanning electron microscopy and confocal laser scanning microscopy results showed that morphological changes during the transition from yeast to hypha and the biofilm formation of C. albicans are repressed by SNH treatment. We also found that SNH can effectively inhibit the biofilm formation of clinical C. albicans strains (Z103, Z3044, Z1402, and Z1407) and SNH in combination with fluconazole, berberine chloride, caspofungin and itraconazole antifungal agents can synergistically inhibit the biofilm formation of C. albicans. Eukaryotic transcriptome sequencing and qRT-PCR results showed that SNH treatment resulted in significantly down-regulated expression in several biofilm formation related genes in the Ras1-cAMP-Efg1 pathway (ALS1, ALA1, ALS3, EAP1, RAS1, EFG1, HWP1, and TEC1) and significantly up-regulated expression in yeast form-associated genes (YWP1 and RHD1). We also found that SNH can effectively reduce the production of key messenger cAMP in the Ras1-cAMP-Efg1 pathway. Furthermore, using Galleria mellonella as an in vivo model we found that SNH can effectively treat C. albicans infection in vivo. Our presented results suggest that SNH exhibits potential antibiofilm effects related to inhibiting the Ras1-cAMP-Efg1 pathway in the biofilm formation of C. albicans.

Antimicrobial Susceptibility Testing of Antimicrobial Peptides to Better Predict Efficacy

During the development of antimicrobial peptides (AMP) as potential therapeutics, antimicrobial susceptibility testing (AST) stands as an essential part of the process in identification and optimisation of candidate AMP. Standard methods for AST, developed almost 60 years ago for testing conventional antibiotics, are not necessarily fit for purpose when it comes to determining the susceptibility of microorganisms to AMP. Without careful consideration of the parameters comprising AST there is a risk of failing to identify novel antimicrobials at a time when antimicrobial resistance (AMR) is leading the planet toward a post-antibiotic era. More physiologically/clinically relevant AST will allow better determination of the preclinical activity of drug candidates and allow the identification of lead compounds. An important consideration is the efficacy of AMP in biological matrices replicating sites of infection, e.g., blood/plasma/serum, lung bronchiolar lavage fluid/sputum, urine, biofilms, etc., as this will likely be more predictive of clinical efficacy. Additionally, specific AST for different target microorganisms may help to better predict efficacy of AMP in specific infections. In this manuscript, we describe what we believe are the key considerations for AST of AMP and hope that this information can better guide the preclinical development of AMP toward becoming a new generation of urgently needed antimicrobials.

Efficacy of a Topical Formulation of Sodium Bicarbonate in Mild to Moderate Stable Plaque Psoriasis: a Randomized, Blinded, Intrapatient, Controlled Study

INTRODUCTION

Psoriasis is a chronic inflammatory disease characterized by the presence of erythematosquamous lesions. A wide variety of topical treatments for therapy of this pathology are available, including sodium bicarbonate (SB). A few papers reported in literature focus on use of SB baths for treatment of psoriasis, but none assess evidence concerning the efficacy of SB topical preparations. This study aimed to determine the effectiveness of a galenic SB in lanette vax formulation compared with lanette vax base in mild to moderate stable plaque psoriasis.

METHODS

A randomized, double-blind, intrapatient, controlled study was performed in 28 days. Thirty patients of both genders were selected for testing. A blinded investigator evaluated the patients' psoriasis using a modified Psoriasis Area and Severity Index (PASI), body surface area (BSA), and objective parameters using sensors (Multiprobe Adapter MPA5; Courage & Khazaka Electronic GmbH, Cologne, Germany).

RESULTS

Data analysis of objective parameters highlighted that use of the SB topical preparation led to no improvement in skin hydration, no reduction in transepidermal water loss, and no decrease of erythema. The modified PASI and BSA did not change from baseline.

CONCLUSIONS

The results obtained show that use of the studied product did not improve psoriatic lesions.

Strong Synergism of Palmatine and Fluconazole/Itraconazole Against Planktonic and Biofilm Cells of Candida Species and Efflux-Associated Antifungal Mechanism

Fungal infections caused by Candida albicans and non-albicans Candida [NAC] species are becoming a growing threat in immunodeficient population, people with long-term antibiotic treatment and patients enduring kinds of catheter intervention. The resistance to one or more than one conventional antifungal agents contributes greatly to the widespread propagation of Candida infections. The severity of fungal infection requires the discovery of novel antimycotics and the extensive application of combination strategy. In this study, a group of Candida standard and clinical strains including C. albicans as well as several NAC species were employed to evaluate the antifungal potentials of palmatine (PAL) alone and in combination with fluconazole (FLC)/itraconazole (ITR) by microdilution method, checkerboard assay, gram staining, spot assay, and rhodamine 6G efflux test. Subsequently, the expressions of transporter-related genes, namely CDR1, CDR2, MDR1, and FLU1 for C. albicans, CDR1 and MDR1 for Candida tropicalis and Candida parapsilosis, ABC1 and ABC2 for Candida krusei, CDR1, CDR2, and SNQ2 for Candida glabrata were analyzed by qRT-PCR. The susceptibility test showed that PAL presented strong synergism with FLC and ITR with fractional inhibitory concentration index (FICI) in a range of 0.0049-0.75 for PAL+FLC and 0.0059-0.3125 for PAL+ITR in planktonic cells, 0.125-0.375 for PAL+FLC and 0.0938-0.3125 for PAL+ITR in biofilms. The susceptibility results were also confirmed by gram staining and spot assay. After combinations, a vast quantity of rhodamine 6G could not be pumped out as considerably intracellular red fluorescence was accumulated. Meanwhile, the expressions of efflux-associated genes were evaluated and presented varying degrees of inhibition. These results indicated that PAL was a decent antifungal synergist to promote the antifungal efficacy of azoles (such as FLC and ITR), and the underlying antifungal mechanism might be linked with the inhibition of efflux pumps and the elevation of intracellular drug content.

Evaluation of disinfectants in order to eliminate fungal contamination in computer keyboards of an integrated health center in Piauí, Brazil

This quantitative and qualitative study aimed to evaluate the level of fungal contamination in computer keyboards from an Integrated Health Center (IHC) at Piauí, Brazil, and to evaluate the efficacy of 50% sodium bicarbonate and 50% alcoholic vinegar solutions to eliminate these microorganisms. Ten keyboards from six sectors of the IHC were chosen randomly, and the collection was performed in three situations: (i) before of disinfection, (ii) after disinfection with solution of sodium bicarbonate, and (iii) after disinfection with solution of alcoholic vinegar. Samples were inoculated in Petri dishes with dextrose agar potato plus chloramphenicol and incubated at room temperature for 72 h. All keyboards were contaminated with opportunistic fungi, with Cladosporium cladosporioides (29.4%) being the most frequent species, followed by Curvularia lunata (17.6%) and Aspergillus niger, Alternaria alternata, and Curvularia clavata with 11.8% each. The two solutions were proven to be efficient in eliminating fungal contamination; however, the sodium bicarbonate solution caused esthetic damages in keyboards. In addition, this study is the first report of the antifungal activity of alcoholic vinegar in filamentous fungi. Based on our findings, we suggest a daily disinfection of keyboards with a 50% vinegar solution plus adequate hygiene from the hands of professionals before and after the use of the computer and its annexes, as key actions to reduce nosocomial infections, particularly in economically disadvantaged countries.

Bicarbonate Alters Bacterial Susceptibility to Antibiotics by Targeting the Proton Motive Force

The antibacterial properties of sodium bicarbonate have been known for years, yet the molecular understanding of its mechanism of action is still lacking. Utilizing chemical-chemical combinations, we first explored the effect of bicarbonate on the activity of conventional antibiotics to infer on the mechanism. Remarkably, the activity of 8 classes of antibiotics differed in the presence of this ubiquitous buffer. These interactions and a study of mechanism of action revealed that, at physiological concentrations, bicarbonate is a selective dissipater of the pH gradient of the proton motive force across the cytoplasmic membrane of both Gram-negative and Gram-positive bacteria. Further, while components that make up innate immunity have been extensively studied, a link to bicarbonate, the dominant buffer in the extracellular fluid, has never been made. Here, we also explored the effects of bicarbonate on components of innate immunity. Although the immune response and the buffering system have distinct functions in the body, we posit there is interplay between these, as the antimicrobial properties of several components of innate immunity were enhanced by a physiological concentration of bicarbonate. Our findings implicate bicarbonate as an overlooked potentiator of host immunity in the defense against pathogens. Overall, the unique mechanism of action of bicarbonate has far-reaching and predictable effects on the activity of innate immune components and antibiotics. We conclude that bicarbonate has remarkable power as an antibiotic adjuvant and suggest that there is great potential to exploit this activity in the discovery and development of new antibacterial drugs by leveraging testing paradigms that better reflect the physiological concentration of bicarbonate.

Synergistic in vitro activity of sodium houttuyfonate with fluconazole against clinical Candida albicans strains under planktonic growing conditions

CONTEXT

Fluconazole resistance is an intractable problem of treating Candida albicans, calling for more antifungal agents to enhance the activity of fluconazole.

OBJECTIVE

This work investigates the anti-C. albicans activities of sodium houttuyfonate (SH) and/or fluconazole and the associated mechanism.

MATERIALS AND METHODS

The minimum inhibitory concentrations (MICs) of SH and fluconazole both ranging from 0.5 to 1024 μg/mL were determined by broth microdilution method in 19 C. albicans isolates, and their fractional inhibitory concentration index (FICI) was evaluated by checkerboard assay. After MIC_SH and/or MIC_fluconazole treatments, the expressions of IFD6, PHR1, ZAP1, ADH5, BGL2, XOG1 and FKS1 were analyzed by quantitative reverse transcription polymerase chain reaction (qRT-PCR) in C. albicans 1601.

RESULTS AND CONCLUSION

The MICs of SH alone ranged from 32 to 256 μg/mL and decreased 2-16-fold in combination. SH showed strong synergism with fluconazole with FICI <0.13-0.5. In C. albicans 1601, we observed that (i) the expression of the seven genes increased notably in a range between 3.71- and 12.63-fold (p < 0.05) when SH was used alone, (ii) the combined use of SH and fluconazole slightly inhibited the expression of IFD6 and PHR1 by 1.23- and 1.35-fold (p > 0.05), but promoted evidently the expression of ZAP1, ADH5, XOG1 and FKS1 by 1.98-, 3.56-, 4.10- and 2.86-fold (p < 0.05). The results suggested SH to be a potential synergist to enhance the antifungal activity of fluconazole in C. albicans resistant isolates, and the underlying mechanism may be associated with β-1,3-glucan synthesis and transportation.

Antifungal Susceptibility Testing of Malassezia spp. with an Optimized Colorimetric Broth Microdilution Method

Malassezia is a genus of lipid-dependent yeasts. It is associated with common skin diseases such as pityriasis versicolor and atopic dermatitis and can cause systemic infections in immunocompromised individuals. Owing to the slow growth and lipid requirements of these fastidious yeasts, convenient and reliable antifungal drug susceptibility testing assays for Malassezia spp. are not widely available. Therefore, we optimized a broth microdilution assay for the testing of Malassezia that is based on the CLSI and EUCAST assays for Candida and other yeasts. The addition of ingredients such as lipids and esculin provided a broth medium formulation that enabled the growth of all Malassezia spp. and could be read, with the colorimetric indicator resazurin, by visual and fluorescence readings. We tested the susceptibility of 52 strains of 13 Malassezia species to 11 commonly used antifungals. MIC values determined by visual readings were in good agreement with MIC values determined by fluorescence readings. The lowest MICs were found for the azoles itraconazole, posaconazole, and voriconazole, with MIC₉₀ values of 0.03 to 1.0 μg/ml, 0.06 to 0.5 μg/ml, and 0.03 to 2.0 μg/ml, respectively. All Malassezia spp. were resistant to echinocandins and griseofulvin. Some Malassezia spp. also showed high MIC values for ketoconazole, which is the most widely recommended topical antifungal to treat Malassezia skin infections. In summary, our assay enables the fast and reliable susceptibility testing of Malassezia spp. with a large panel of different antifungals.

The roles of CDR1, CDR2, and MDR1 in kaempferol-induced suppression with fluconazole-resistant Candida albicans

CONTEXT

Fungal infections caused by fluconazole-resistant Candida albicans are an intractable clinical problem, calling for new efficient antifungal drugs. Kaempferol, an active flavonoid, has been considered a potential candidate against Candida species.

OBJECTIVE

This work investigates the resistance reversion of kaempferol in fluconazole-resistant C. albicans and the underlying mechanism.

MATERIALS AND METHODS

The antifungal activities of fluconazole and/or kaempferol were assessed by a series of standard procedures including broth microdilution method, checkerboard assay and time-kill (T-K) test in nine clinical strains as well as a standard reference isolate of C. albicans. Subsequently, the morphological changes, the efflux of rhodamine 6G, and the expressions of CDR 1, CDR 2, and MDR 1 were analysed by scanning electron microscope (SEM), inverted fluorescence microscope and quantitative reverse transcription polymerase chain reaction (qRT-PCR) in C. albicans z2003.

RESULTS

For all the tested C. albicans strains, the minimum inhibitory concentrations (MICs) of fluconazole and kaempferol ranged 0.25-32 and 128-256 μg/mL with a range of fractional inhibitory concentration index of 0.257-0.531. In C. albicans z2003, the expression of both CDR 1 and CDR 2 were decreased after exposure to kaempferol alone with negligible rhodamine 6G accumulation, while the expression of CDR 1, CDR 2 and MDR 1 were all decreased when fluconazole and kaempferol were used concomitantly with notable fluorescence of rhodamine 6G observed.

DISCUSSION AND CONCLUSION

Kaempferol-induced reversion in fluconazole-resistant C. albicans might be likely due to the suppression of the expression of CDR1, CDR2 and MDR1.

Formic acid and acetic acid induce a programmed cell death in pathogenic Candida species

Cutaneous fungal infections are common and widespread. Antifungal agents used for the treatment of these infections often have undesirable side effects. Furthermore, increased resistance of the microorganisms to the antifungal drugs becomes the growing problem. Accordingly, the search for natural antifungal compounds continues to receive attention. Apoptosis is highly regulated programmed cell death. During yeast cell apoptosis, amino acids and peptides are released and can stimulate regeneration of human epithelium cells. Thus, detection of chemical compounds inducing apoptosis in yeast and nontoxic for humans is of great medical relevance. The aim of this study was to detect chemical compound inducing apoptosis in pathogenic Candida species with the lowest toxicity to the mammalian cells. Five chemical compounds--acetic acid, sodium bicarbonate, potassium carbonate, lithium acetate, and formic acid--were tested for evaluation of antifungal activity on C. albicans, C. guilliermondii, and C. lusitaniae. The results showed that acetic acid and formic acid at the lowest concentrations induced yeast cells death. Apoptosis analysis revealed that cells death was accompanied by activation of caspase. Minimal inhibitory concentrations of potassium carbonate and sodium bicarbonate induced Candida cells necrosis. Toxicity test with mammalian cell cultures showed that formic acid has the lowest effect on the growth of Jurkat and NIH 3T3 cells. In conclusion, our results show that a low concentration of formic acid induces apoptosis-like programmed cell death in the Candida yeast and has a minimal effect on the survivability of mammalian cells, suggesting potential applications in the treatment of these infections.