scholarly journals The Effects of Tormentic Acid and Extracts from Callistemon citrinus on Candida albicans and Candida tropicalis Growth and Inhibition of Ergosterol Biosynthesis in Candida albicans

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Chido Bvumbi ◽  
Godloves Fru Chi ◽  
Marc Y. Stevens ◽  
Molly Mombeshora ◽  
Stanley Mukanganyama
Keyword(s):  
Candida Albicans ◽  
Antifungal Activity ◽  
Candida Tropicalis ◽  
Methanol Extract ◽  
Fungal Infections ◽  
Water Extract ◽  
Antifungal Drugs ◽  
Ergosterol Content ◽  
Broth Microdilution Method ◽  
Tormentic Acid

Candida albicans and Candida tropicalis are the leading causes of human fungal infections worldwide. There is an increase in resistance of Candida pathogens to existing antifungal drugs leading to a need to find new sources of antifungal agents. Tormentic acid has been isolated from different plants including Callistemon citrinus and has been found to possess antimicrobial properties, including antifungal activity. The study aimed to determine the effects of tormentic and extracts from C. citrinus on C. albicans and C. tropicalis and a possible mode of action. The extracts and tormentic acid were screened for antifungal activity using the broth microdilution method. The growth of both species was inhibited by the extracts, and C. albicans was more susceptible to the extract compared to C. tropicalis. The growth of C. albicans was inhibited by 80% at 100 μg/ml of both the DCM: methanol extract and the ethanol: water extract. Tormentic acid reduced the growth of C. albicans by 72% at 100 μg/ml. The effects of the extracts and tormentic acid on ergosterol content in C. albicans were determined using a UV/Vis scanning spectrophotometer. At concentrations of tormentic acid of 25 μg/ml, 50 μg/ml, 100 μg/ml, and 200 μg/ml, the content of ergosterol was decreased by 22%, 36%, 48%, and 78%, respectively. Similarly, the DCM: methanol extract at 100 μg/ml and 200 μg/ml decreased the content by 78% and 88%, respectively. A dose-dependent decrease in ergosterol content was observed in cells exposed to miconazole with a 25 μg/ml concentration causing a 100% decrease in ergosterol content. Therefore, tormentic acid inhibits the synthesis of ergosterol in C. albicans. Modifications of the structure of tormentic acid to increase its antifungal potency may be explored in further studies.

Efficacy of Novel Schiff base Derivatives as Antifungal Compounds in Combination with Approved Drugs Against Candida Albicans

2019 ◽  
Vol 15 (6) ◽  
pp. 648-658 ◽  
Author(s):  
Manzoor Ahmad Malik ◽  
Shabir Ahmad Lone ◽  
Parveez Gull ◽  
Ovas Ahmad Dar ◽  
Mohmmad Younus Wani ◽  
...  
Keyword(s):  
Schiff Base ◽  
Candida Albicans ◽  
Antifungal Activity ◽  
Fungal Infections ◽  
Total Sterol ◽  
Antifungal Drugs ◽  
New Drugs ◽  
Ergosterol Biosynthesis ◽  
Dependent Manner ◽  
Schiff Base Derivatives

Background: The increasing incidence of fungal infections, especially caused by Candida albicans, and their increasing drug resistance has drastically increased in recent years. Therefore, not only new drugs but also alternative treatment strategies are promptly required. Methods: We previously reported on the synergistic interaction of some azole and non-azole compounds with fluconazole for combination antifungal therapy. In this study, we synthesized some non-azole Schiff-base derivatives and evaluated their antifungal activity profile alone and in combination with the most commonly used antifungal drugs- fluconazole (FLC) and amphotericin B (AmB) against four drug susceptible, three FLC resistant and three AmB resistant clinically isolated Candida albicans strains. To further analyze the mechanism of antifungal action of these compounds, we quantified total sterol contents in FLC-susceptible and resistant C. albicans isolates. Results: A pyrimidine ring-containing derivative SB5 showed the most potent antifungal activity against all the tested strains. After combining these compounds with FLC and AmB, 76% combinations were either synergistic or additive while as the rest of the combinations were indifferent. Interestingly, none of the combinations was antagonistic, either with FLC or AmB. Results interpreted from fractional inhibitory concentration index (FICI) and isobolograms revealed 4-10-fold reduction in MIC values for synergistic combinations. These compounds also inhibit ergosterol biosynthesis in a concentration-dependent manner, supported by the results from docking studies. Conclusion: The results of the studies conducted advocate the potential of these compounds as new antifungal drugs. However, further studies are required to understand the other mechanisms and in vivo efficacy and toxicity of these compounds.

scholarly journals Synergistic Antifungal Activity of Chitosan with Fluconazole against Candida albicans, Candida tropicalis, and Fluconazole-Resistant Strains

Molecules ◽  
2020 ◽  
Vol 25 (21) ◽  
pp. 5114
Author(s):  
Wei-Hsuan Lo ◽  
Fu-Sheng Deng ◽  
Chih-Jung Chang ◽  
Ching-Hsuan Lin
Keyword(s):  
Candida Albicans ◽  
Antifungal Activity ◽  
Candida Tropicalis ◽  
Inhibitory Effect ◽  
Antifungal Drugs ◽  
Drug Resistant ◽  
Combinational Treatment ◽  
Fluconazole Resistant ◽  
Resistant Strains ◽  
Drug Resistant Strains

(1) Background: Few antifungal drugs are currently available, and drug-resistant strains have rapidly emerged. Thus, the aim of this study is to evaluate the effectiveness of the antifungal activity from a combinational treatment of chitosan with a clinical antifungal drug on Candida albicans and Candida tropicalis. (2) Methods: Minimum inhibitory concentration (MIC) tests, checkerboard assays, and disc assays were employed to determine the inhibitory effect of chitosan with or without other antifungal drugs on C. albicans and C. tropicalis. (3) Results: Treatment with chitosan in combination with fluconazole showed a great synergistic fungicidal effect against C. albicans and C. tropicalis, but an indifferent effect on antifungal activity when challenged with chitosan-amphotericin B or chitosan-caspofungin simultaneously. Furthermore, the combination of chitosan and fluconazole was effective against drug-resistant strains. (4) Conclusions: These findings provide strong evidence that chitosan in combination with fluconazole is a promising therapy against two Candida species and its drug-resistant strains.

scholarly journals Effect of seasonality on chemical profile and antifungal activity of essential oil isolated from leaves Psidium salutare (Kunth) O. Berg

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5476 ◽  
Author(s):  
Delmacia G. de Macêdo ◽  
Marta Maria A. Souza ◽  
Maria Flaviana B. Morais-Braga ◽  
Henrique Douglas M. Coutinho ◽  
Antonia Thassya L. dos Santos ◽  
...  
Keyword(s):  
Candida Albicans ◽  
Chemical Composition ◽  
Antifungal Activity ◽  
Essential Oil ◽  
Essential Oils ◽  
Fungal Infections ◽  
Fungal Resistance ◽  
Chemical Profile ◽  
Minimum Fungicidal Concentration ◽  
Broth Microdilution Method

Medicinal plants play a crucial role in the search for components that are capable of neutralizing the multiple mechanisms of fungal resistance. Psidium salutare (Kunth) O. Berg is a plant native to Brazil used as both food and traditional medicine to treat diseases and symptoms such as stomach ache and diarrhea, whose symptoms could be related to fungal infections from the genus Candida. The objective of this study was to investigate the influence of seasonal variability on the chemical composition of the Psidium salutare essential oil, its antifungal potential and its effect on the Candida albicans morphogenesis. The essential oils were collected in three different seasonal collection periods and isolated by the hydrodistillation process in a modified Clevenger apparatus with identification of the chemical composition determined by gas chromatography coupled to mass spectrometry (GC/MS). The antifungal assays were performed against Candida strains through the broth microdilution method to determine the minimum fungicidal concentration (MFC). Fungal growth was assessed by optical density reading and the Candida albicans dimorphic effect was evaluated by optical microscopy in microculture chambers. The chemical profile of the essential oils identified 40 substances in the different collection periods with γ-terpinene being the predominant constituent. The antifungal activity revealed an action against the C. albicans, C. krusei and C. tropicalis strains with an IC50 ranging from 345.5 to 2,754.2 µg/mL and a MFC higher than 1,024 µg/mL. When combined with essential oils at sub-inhibitory concentrations (MIC/16), fluconazole had its potentiated effect, i.e. a synergistic effect was observed in the combination of fluconazole with P.salutare oil against all Candida strains; however, for C. albicans, its effect was reinforced by the natural product in all the collection periods. The results show that the Psidium salutare oil affected the dimorphic transition capacity, significantly reducing the formation of hyphae and pseudohyphae in increasing concentrations. The results show that P. salutare oil exhibits a significant antifungal activity against three Candida species and that it can act in synergy with fluconazole. These results support the notion that this plant may have a potential use in pharmaceutical and preservative products.

Antifungal Activity of Peppermint Oil against Candida Albicans Isolated from Urine Samples

2019 ◽  
Vol 12 (4) ◽  
pp. 4611-4615
Author(s):  
Noura Berakda ◽  
Abdulkarim Radwan
Keyword(s):  
Candida Albicans ◽  
Urinary Tract ◽  
Antifungal Activity ◽  
Fungal Infections ◽  
In Vitro Study ◽  
Inhibition Zone ◽  
Antifungal Drugs ◽  
University Hospital ◽  
Peppermint Oil

Fungal infections with candida species are an important cause of morbidity and mortality. Situation is further worsened by increasing resistance to antifungal drugs. In this study, we sought to investigate the antifungal activity of peppermint oil against candida albicans of urinary tract candidiasis in females from Syria. An in vitro study was carried out using the following Candida albicans strains involved in urinary tract candidiasis using well diffusion (WD) testing: Candida albicans (ATCC 90028) and 15 strains were compiled from Aleppo university Hospital. It was taken from women having urinary tract candidiasis. The antifungal activity of peppermint oil was determined in the form of inhibition zone using antifungal assay agar WD testing. In all experiments, the obtained results indicated that peppermint oil has inhibitory effects on Candida albicans (ATCC 90028) and some 15 strains. This study showed that peppermint oil was active against the tested Candida albicans strains. Peppermint oil was more effective against Candida albicans compared to fluconazole. Peppermint oil may have potential for use in the development of clinically useful antifungal preparations. Therefore, peppermint oil might be highly effective in the natural prevention treatment of urinary tract candidiasis.

scholarly journals High-Throughput Screening of a Collection of Known Pharmacologically Active Small Compounds for Identification of Candida albicans Biofilm Inhibitors

2013 ◽  
Vol 57 (8) ◽  
pp. 3681-3687 ◽  
Author(s):  
Samuel A. Siles ◽  
Anand Srinivasan ◽  
Christopher G. Pierce ◽  
José L. Lopez-Ribot ◽  
Anand K. Ramasubramanian
Keyword(s):  
Candida Albicans ◽  
Antifungal Activity ◽  
Biofilm Formation ◽  
High Throughput Screening ◽  
Fungal Infections ◽  
Rapid Development ◽  
Unmet Need ◽  
Antifungal Drugs ◽  
Content Type ◽  
Pharmacologically Active

ABSTRACTCandida albicansis the most common etiologic agent of systemic fungal infections with unacceptably high mortality rates. The existing arsenal of antifungal drugs is very limited and is particularly ineffective againstC. albicansbiofilms. To address the unmet need for novel antifungals, particularly those active against biofilms, we have screened a small molecule library consisting of 1,200 off-patent drugs already approved by the Food and Drug Administration (FDA), the Prestwick Chemical Library, to identify inhibitors ofC. albicansbiofilm formation. According to their pharmacological applications that are currently known, we classified these bioactive compounds as antifungal drugs, as antimicrobials/antiseptics, or as miscellaneous drugs, which we considered to be drugs with no previously characterized antifungal activity. Using a 96-well microtiter plate-based high-content screening assay, we identified 38 pharmacologically active agents that inhibitC. albicansbiofilm formation. These drugs were subsequently tested for their potency and efficacy against preformed biofilms, and we identified three drugs with novel antifungal activity. Thus, repurposing FDA-approved drugs opens up a valuable new avenue for identification and potentially rapid development of antifungal agents, which are urgently needed.

scholarly journals ANTIFUNGAL ACTIVITY OF THE ASSOCIATION OF CARVACROL WITH AMPHOTERICIN B OR WITH KETOCONAZOLE

2019 ◽  
Vol 16 (31) ◽  
pp. 12-17
Author(s):  
Gustavo Lima SOARES ◽  
Brenda Lavínia Calixto dos SANTOS ◽  
Brenna Ravena Araújo LUZ ◽  
Wylly Araújo de OLIVEIRA
Keyword(s):  
Antifungal Activity ◽  
Amphotericin B ◽  
Inhibitory Concentration ◽  
Fungal Infections ◽  
Antifungal Drugs ◽  
Aspergillus Species ◽  
Microdilution Method ◽  
Broth Microdilution Method ◽  
Antifungal Action

Aspergillus species are a cause of a high number of fungal infections of difficult treatment, presenting an expressive number of deaths due to the complications in the severe cases of infection. The objective was to evaluate the antifungal action of carvacrol against Aspergillus species, as well as to evaluate the interactions when associated with amphotericin B or ketoconazole. The antifungal activity of carvacrol was evaluated by the broth microdilution method. The combinations of the substances were performed by the checkerboard methodology, to determine the Index of Fractional Inhibitory Concentration. Carvacrol showed antifungal activity against all Aspergillus strains used in the trials. In combinations of substances, only a combination of carvacrol and amphotericin B presented satisfactory results. Combinations of carvacrol and ketoconazole have not shown good. It is concluded that carvacrol is a good candidate for the antifungal drug because of its good activity against Aspergillus demonstrated in the present study, as well as in other studies in the literature. Their combination in vitro with amphotericin B or ketoconazole did not present any advantages over the use of antifungal drugs alone.

Antifungal efficacy of atorvastatin-containing emulgel in the treatment of oral and vulvovaginal candidiasis

2020 ◽  
Author(s):  
Ari Soares de Oliveira Neto ◽  
Israel Lucas Antunes Souza ◽  
Maria Eliza Samuel Amorim ◽  
Thalita de Freitas Souza ◽  
Vinicius Novaes Rocha ◽  
...  
Keyword(s):  
Candida Albicans ◽  
Antifungal Activity ◽  
Inhibitory Concentration ◽  
Fungal Infections ◽  
Drug Repositioning ◽  
Oral Candidiasis ◽  
Vulvovaginal Candidiasis ◽  
Antifungal Drugs ◽  
Sterol Synthesis ◽  
In Vitro Tests

Abstract Drug repositioning has been an important ally in the search for new antifungal drugs. Statins are drugs that act to prevent sterol synthesis in both humans and fungi and for this reason they are promissory candidates to be repositioned to treat mycoses. In this study we evaluated the antifungal activity of atorvastatin by in vitro tests to determine the minimum inhibitory concentration against azole resistant Candida albicans and its mechanisms of action. Moreover, the efficacy of both atorvastatin-loaded oral and vaginal emulgels (0.75%, 1.5% and 3% w/w) was evaluated by means of in vivo experimental models of oral and vulvovaginal candidiasis, respectively. The results showed that atorvastatin minimal inhibitory concentration against C. albicans was 31.25 μg/ml. In oral candidiasis experiments, the group treated with oral emulgel containing 3.0% atorvastatin showcased total reduction in fungal load after nine days of treatment. Intravaginal delivery atorvastatin emulgel showed considerable effectiveness at the concentration of 3% (65% of fungal burden reduction) after nine days of treatment. From these findings, it is possible to assert that atorvastatin may be promising for drug repositioning towards the treatment of these opportunistic mycoses. Lay Summary Atorvastatin is a statin drug that presents antifungal activity. This study showed that atorvastatin-containing oral and vaginal emulgels were able to treat vulvovaginal and oral candidiasis of infected animal model. Therefore, we showcased that atorvastatin may be a possible therapeutic agent in order to be a used to control opportunistic mucosal fungal infections caused by Candida albicans.

GROWTH INHIBITORY ACTIVITIES OF THE RHIZOME CRUDE EXTRACT OF Curcuma longa ON THE HUMAN PATHOGENIC FUNGUS Mucor circinelloides

2020 ◽  
Vol 65 (10) ◽  
pp. 82-91
Author(s):  
Phuong Nguyen Anh ◽  
Mai Le Thi Tuyet ◽  
Trung Trieu Anh
Keyword(s):  
Antifungal Activity ◽  
Crude Extract ◽  
Fungal Infections ◽  
Early Stage ◽  
Curcuma Longa ◽  
Pathogenic Fungus ◽  
Mucor Circinelloides ◽  
Antifungal Drugs ◽  
Diffusion Method ◽  
Dilution Method

Mucormycosis is an uncommon but life-threatening invasive fungal infection, mostly occurs in immunocompromised patients. Lacking the appropriate antifungal drugs is one of the reasons that lead to difficulties in the management of mucormycosis. Curcuma longa has been used traditionally and widely to treat various diseases, including fungal infections. In the search for novel antifungal compounds from natural resources, we evaluated the effect of rhizome crude extract of C. longa on Mucor circinelloides – a causal agent of mucormycosis. The results of screening, using broth dilution method and agar-well diffusion method, showed that the C. longa extract exhibited promising antifungal activity against the fungus M. circinelloides. In liquid medium, C. longa extract decreased the ability of spore germination and the speed of hyphae formation of M. circinelloides decreased by up to approximately 70% and 90%, respectively. Besides, in a solid medium, the crude extract presented similar activity with amphotericin B (400 μg\mL) in decreasing the growth of M. circinelloides by nearly 77%. Moreover, the extract of C. longa also likely to induce the yeast-like type of growth of the dimorphic M. circinelloides in the early stage. These results suggest the plant could be a potential source for further study on biochemical components and the mechanism of its antifungal activity.

scholarly journals ANTI-CANDIDA ALBICANS ACTIVITY OF THE ASSOCIATION OF CITRONELAL WITH ANFOTERICIN B OR WITH CETOCONAZOLE

2019 ◽  
Vol 16 (31) ◽  
pp. 250-257
Author(s):  
Patrícia Duarte Costa SILVA ◽  
Brenda Lavínia Calixto dos SANTOS ◽  
Gustavo Lima SOARES ◽  
Wylly Araújo de OLIVEIRA
Keyword(s):  
Candida Albicans ◽  
Antifungal Activity ◽  
Amphotericin B ◽  
Inhibitory Concentration ◽  
Fungal Infections ◽  
Pathogenic Fungi ◽  
Mortality Rates ◽  
New Drugs ◽  
High Morbidity ◽  
Isolated Species

Fungal infections caused by species of the genus Candida are responsible for high morbidity and mortality rates, mainly affecting immunocompromised individuals. Among fungi, Candida albicans is the most frequently isolated species of clinical specimens. A problem associated with increased resistance of pathogenic fungi to the agents used in the therapeutic regimen and the limited number of drugs to cure these infections. As a result, the search for new drugs with antifungal activity has become increasingly important. The aim of this study is to study the antifungal activity of citronellal alone and in combination with amphotericin B or ketoconazole. The Minimal Inhibitory Concentration of citronellal, amphotericin B and ketoconazole against strains of Candida albicans were evaluated by the microdilution technique, and the Minimum Fungicide Concentration of citronellal against the same strains was also performed. Through the checkerboard methodology the effect of the combination of citronelal with amphotericin B or with ketoconazole was determined. This study showed that the association of citronellal with ketoconazole was shown to be an additive against one of the strains of C. albicans and indifferent to another strain. While the combined activity of citronellal and amphotericin B demonstrated an indifferent effect on the strains tested.

scholarly journals Novel Antifungal Compounds Discovered in Medicines for Malaria Venture’s Malaria Box

mSphere ◽  
2018 ◽  
Vol 3 (2) ◽  
Author(s):  
Eric H. Jung ◽  
David J. Meyers ◽  
Jürgen Bosch ◽  
Arturo Casadevall
Keyword(s):  
Candida Albicans ◽  
Antifungal Activity ◽  
Cryptococcus Neoformans ◽  
Fungal Pathogens ◽  
Pathogenic Fungi ◽  
Cryptococcus Gattii ◽  
Antifungal Drugs ◽  
Resistant Bacteria ◽  
Animal Cells ◽  
Malaria Box

ABSTRACTSimilarities in fungal and animal cells make antifungal discovery efforts more difficult than those for other classes of antimicrobial drugs. Currently, there are only three major classes of antifungal drugs used for the treatment of systemic fungal diseases: polyenes, azoles, and echinocandins. Even in situations where the offending fungal organism is susceptible to the available drugs, treatment courses can be lengthy and unsatisfactory, since eradication of infection is often very difficult, especially in individuals with impaired immunity. Consequently, there is a need for new and more effective antifungal drugs. We have identified compounds with significant antifungal activity in the Malaria Box (Medicines for Malaria Ventures, Geneva, Switzerland) that have higher efficacy than some of the currently used antifungal drugs. Our best candidate, MMV665943 (IUPAC name 4-[6-[[2-(4-aminophenyl)-3H-benzimidazol-5-yl]methyl]-1H-benzimidazol-2-yl]aniline), here referred to as DM262, showed 16- to 32-fold-higher activity than fluconazole againstCryptococcus neoformans. There was also significant antifungal activity in other fungal species with known antifungal resistance, such asLomentospora prolificansandCryptococcus gattii. Antifungal activity was also observed against a common fungus,Candida albicans. These results are important because they offer a potentially new class of antifungal drugs and the repurposing of currently available therapeutics.IMPORTANCEMuch like the recent increase in drug-resistant bacteria, there is a rise in antifungal-resistant strains of pathogenic fungi. There is a need for novel and more potent antifungal therapeutics. Consequently, we investigated a mixed library of drug-like and probe-like compounds with activity inPlasmodiumspp. for activity against two common fungal pathogens,Cryptococcus neoformansandCandida albicans, along with two less common pathogenic species,Lomentospora prolificansandCryptococcus gattii. We uncover a previously uncharacterized drug with higher broad-spectrum antifungal activity than some current treatments. Our findings may eventually lead to a compound added to the arsenal of antifungal therapeutics.

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