Determination Of Antifungal Activity Research Articles

Determination of Antifungal Activities on Some Plant Extracts on Alternaria alternata

To increase yield and quality in agricultural production, it is necessary to perform management against diseases and pests. Alternaria, which causes several diseases in many economically important plants, is the most common species and widely distributed in nature. One of the important species reported in sweet cherry in recent years is Alternaria alternata. Many studies have emphasized the necessity of effective control with Alternaria species and examined the use of environmentally friendly methods against fungal diseases. In recent years, the use of plant extracts has increased due to their antimicrobial properties. Antifungal effects of Datura stramonium L., Vitex agnus-castus L., Xanthium strumarium L., Capsella bursa-pastoris L., Convolvulus arvensis L., Viscum album L., Echinophora tenuifolia L. subsp. sibthorpiana (Guss.) Tutin, Amaranthus retroflexus L., Chenopodium album L., Tribulus terrestris L., Solanum nigrum L., Nerium oleander L., Circium arvense (L.) Scop. and Brassica oleracea L. aqueous extracts were determined against Alternaria alternata. At the end of the 7-day incubation period, the mycelial growth of the fungi was measured and the antifungal effect of plant extracts was determined. As a result, the extracts were determined to inhibit mycelial growth compared to control. The plant water extracts used in the study were determined to inhibit the mycelial development of the pathogen by 20.20% to 77.12%. It is considered that different solvents and concentrations should be addressed to guide further studies. It was also concluded that potential plant species that may show anti-fungal properties should be evaluated.

The Antifungal Activities of Syzygium aromaticum and Alpinia purpurata Extracts Against Candida krusei: Bioactivity Tests, Molecular Modeling, and Toxicity Tests.

Candida krusei is the cause of the fungal infection candidiasis, which has a high mortality rate. Intrinsic resistance to fluconazole can cause the failure of Krusei candidiasis treatment. Therefore, it is necessary to find alternative drugs to eliminate the fungus. Extracts of Syzygium aromaticum and Alpinia purpurata have been proven to be alternative solutions for treating Candida krusei resistance. This study aims to explore the active compounds Syzygium aromaticum and Alpinia purpurata as treatments against Candida krusei through bioactivity tests, molecular modeling, and toxicity tests. Determination of antifungal activity with the agar well diffusion and microbroth dilution method. Molecular modeling was conducted using the following software: Marvin Sketch, LigandScout 4.4.5, AutoDock ver 4.2.6, PyMOL, LigPlus, MOE ver 2008. Bioactivity test results of the two natural extracts against C. krusei ATCC 6258, it was found that the S. aromaticum and A. purpurata extracts have MIC50 values of 0.031 μg/mL and 1.435x105 μg/mL. The molecular modeling found that the compounds Benzotriazole, 1-(4-methyl-3-nitrobenzoyl)-, 1,3,4-Eugenol Acetate, Stigmasta-5,22-dien-3-ol, acetate (3 beta)- and Farnesyl acetate from the two natural extracts, interacts with the active site of the enzyme lanosterol-14-α-demethylase with a binding energy of -8.91, -6.04, -13.53, and -7.15 kcal/mol. The oral acute toxicity test of S. aromaticum and A. purpurata extracts proved that the LD50 was >6000 mg/kg BW and >8000 mg/kg BW. The acute dermal toxicity test of the two extracts showed that the LD50 was >6000 mg/kg BW. S. aromaticum and A. purpurata extracts have been proven to be alternative solutions for treating Candida krusei resistance.

Determination of antifungal activity and action mechanism of the modified Aurein 1.2 peptide derivatives

BackgroundWith the emergence of drug-resistant fungi and the increased population prone to fungal infections, more effective antifungal drugs are needed. Aurein 1.2 is a potent antimicrobial peptide. Here, we designed a novel derivative of Aurein 1.2, called Aurein N3, which is a modified form of Aurein N2 (another Aurein 1.2 derivative), in which Lys 8 residue was replaced with Leu 13, and was also modified by creating two other mutations. MethodsAurein N3 was designed using several algorithms and docking studies. All peptides were synthesized and some of their bio-activity indices such as antifungal properties on 11 fungi, cytotoxicity, hemolysis, and time of the killing were investigated. Electron microscopy, lived/dead staining, and ergosterol binding assay were performed to study their mechanism of action. ResultsIn comparison to Aurein 1.2 and N2, the docking studies showed that Aurein N3 has reduced binding energy toward ergosterol. The antifungal assessments showed that both Aurein N2 and N3 had strong activity against many fungi. Aurein N3 had lower cytotoxicity and higher binding capability to ergosterol. The hemolytic activity of Aurein N2 and N3 was less than parental Aurein 1.2. All peptides were able to attack the cell wall/membrane and enter the fungi cells. ConclusionHere we introduced a novel derivative of Aurein 1.2 which has lower cytotoxicity, higher ergosterol-binding capability, and comparable antifungal activity compared to the original peptides. It can bind to ergosterol and can also attack the cell wall/membrane of fungi, although more studies are required to find its accurate mechanism of action.

The Citrus reticulata essential oil: evaluation of antifungal activity against penicillium species related to bakery products spoilage

Fungal food spoilage plays a key role in the deterioration of food products, and finding a suitable natural preservative can solve this problem. Therefore, antifungal activity of green mandarin (Citrus reticulata) essential oil (GMEO) in the vapor phase against the growth of Penicillium (P.) expansum and P. chrysogenum inoculated on wheat bread (in situ experiment) was investigated in the current research. The volatile compounds of the GMEO were analyzed by a gas chromatograph coupled to a mass spectrometer (GC–MS), and its antioxidant activity was determined by testing free radical-scavenging capacity (DPPH assay). Moreover, the disc diffusion method was used to analyze the antifungal activity of GMEO in in vitro conditions. The results demonstrate that the Citrus reticulata EO consisted of α-limonene as the most abundant component (71.5%), followed by γ-terpinene (13.9%), and β-pinene (3.5%), and it displayed the weak antioxidant activity with the value of inhibition 5.6 ±0.7%, which corresponds to 103.0 ±6.4 µg TEAC.mL-1. The findings from the GMEO antifungal activity determination revealed that values for the inhibition zone with disc diffusion method ranged from 0.00 ±0.00 (no antifungal effectiveness) to 5.67 ±0.58 mm (moderate antifungal activity). Finally, exposure of Penicillium strains growing on bread to GMEO in vapor phase led to the finding that 250 μL.L-1 of GMEO exhibited the lowest value for mycelial growth inhibition (MGI) of P. expansum (-51.37 ±3.01%) whose negative value reflects even supportive effect of the EO on the microscopic fungus growth. On the other hand, GMEO at this concentration (250 μL.L-1) resulted in the strongest inhibitory action (MGI: 54.15 ±1.15%) against growth of P. chrysogenum. Based on the findings it can be concluded that GMEO in the vapor phase is not an effective antifungal agent against the growth of P. expansum inoculated on bread; however, its antifungal potential manifested against P. chrysogenum suggests GMEO to be an appropriate alternative to the use of chemical inhibitors for bread preservation.

Determination of Antifungal Activity Against Invasive Candidiasis Agents and Trace Element Content of Fig Tree Latex Samples Obtained From Trabzon Province

Candidiasis is a major health concern causing both morbidity and mortality. The increasing prevalence of antimicrobial-resistant fungi associated with life-threatening systemic mycoses, led a constant need for new antifungal agents. Herbal medicines have been tried for this purpose for centuries. The antifungal effect of fig tree latex has been reported and some trace elements such as zinc were associated with antifungal effects. The aim of this study was to determine the trace element content and in-vitro antifungal activity of fig tree latex sample against C. albicans, C. glabrata, C. tropicalis and C. Krusei. Fig tree latex samples were obtained from four different fig tree at Trabzon province in July 2019. The broth microdilution technique was performed to investigate antifungal activity against standard Candida strains and trace elements level were detected with Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-OES) analyzer. The most powerful antifungal activity was reached at a concentration of 0.5 for C. albicans and C. tropicalis, and at a concentration of 0.125 for C. krusei and C. glabrata in fig tree latex. According to trace element analysis, magnesium had the highest level, followed by calcium and phosphorus. Selenium, aluminium, lead and nickel levels were too low to be measured. As a conclusion, fig tree latex has an antifungal potential against Candida species and this may be caused by the high level of magnesium that it contains, however more studies are needed to understand the therapeutic effects of fig tree latex.

New N-phenylacetamide-linked 1,2,3-triazole-tethered coumarin conjugates: Synthesis, bioevaluation, and molecular docking study.

A series of new 1,2,3-triazole-tethered coumarin conjugates linked by N-phenylacetamide was efficiently synthesized via the click chemistry approach in excellent yields. The synthesized conjugates were evaluated for their in vitro antifungal and antioxidant activities. Antifungal activity determination was carried out against fungal strains such as Candida albicans, Fusarium oxysporum, Aspergillus flavus, Aspergillus niger and Cryptococcus neoformans. Compounds 7b, 7d, 7e, 8b and 8e displayed higher potency than the standard drug miconazole, with lower minimum inhibitory concentration values. Also, compound 7a exhibited potential radical scavenging activity as compared with the standard antioxidant butylated hydroxytoluene. In addition, a molecular docking study of the newly synthesized compounds was carried out, and the results showed a good binding mode at the active site of the fungal (C. albicans) P450 cytochrome lanosterol 14α-demethylase enzyme. Furthermore, the synthesized compounds were also tested for ADME properties, and they demonstrated potential as good candidates for oral drugs.

A Eco-friendly management of seed borne mycoflora of Mustard (Brassica sp.) through botanicals and determination of antifungal activity by SEM.

The study was planned to investigate the efficiency of Plant extract of Moringa oleifera against, Datura stramonium , Azadirachta indica and Corton bonplandianum against some seed born fungi (Aspergillus sp., Rhizopus sp., Fusarium sp., Alternaria sp., Cochleobolus sp., Rhizoctonia sp.) isolated from oil seed (Jhumi) using standard microbiological procedures and to investigate effectiveness of plant extract on seed borne mycoflora by SEM study. The process well diffusion method is used to study the efficacy of Plant extract. The extracts were poured into the wells at different concentrations like 50mg/ml, 100mg/ml, 200mg/ml and 400mg/ml. After incubation zones of inhibition was carried out by agar plate observed. As the concentrations of extracts increased the activity also increased and thus the zones of inhibition too increase. Hence Moringa oleifera, Datura stramonium, Azadirachta indica and Corton bonplandianum can be used against various seed born fungal disease.

Refining the therapeutic range of posaconazole and isavuconazole for efficient therapeutic drug monitoring using a bioassay approach.

Therapeutic drug monitoring (TDM) of antifungal triazole was recommended, except for isavuconazole (ISA) whose target trough concentrations (Cmin ) need to be specified. Concerning posaconazole (POS), tablet formulation results in higher exposure but no upper Cmin threshold has been yet proposed. We aimed to investigate the pharmacokinetic-pharmacodynamic relationship of POS and ISA, using a bioassay approach as surrogate marker of antifungal activity, in order to refine the therapeutic Cmin of both antifungals. A bioassay using a cellulose disk diffusion method was performed to determine the growth inhibition zone (GIZ) of POS and ISA on Aspergillus fumigatus and Candida parapsilosis (ISA only). GIZs of plasma from patients undergoing TDM for POS (n=136) or ISA (n=40) were determined. GIZs of plasma patients and antifungal Cmin were highly correlated for ISA (A.fumigatus: ρ=0.942, P<0.0001; C.parapsilosis: ρ=0.949, P<0.0001) and POS (ρ=0.922, P<0.0001), and these relationships were represented with a Michaelis-Menten model. Based on this modeling, the recommended thresholds of 0.7, 1, and 1.25mg/L for the POS Cmin corresponded to 50.1, 55.2, and 59.1% of the maximal GIZ, respectively. We propose an upper threshold of 4.8mg/L for the POS Cmin and a lower threshold of 2.0mg/L for the Cmin of ISA, as they respectively corresponded to concentrations leading to 90% and 50% of the maximal GIZ on A.fumigatus. The determination of antifungal activity using this bioassay allowed refining target Cmin of POS and ISA, especially the upper threshold of POS (4.8mg/L) and the lower threshold of ISA (2.0mg/L).

Dicationic triazolium fungicidal ionic liquids with herbicidal properties

The purpose of the present study was to synthesize the dicationic ionic liquids exhibiting herbicidal and fungicidal activities. A homologue series of ten dicationic ionic liquids was synthesized using commercial triazole fungicide (tebuconazole) and evaluated in terms of their possible antifungal and herbicidal activities. Dicationic triazolium compounds containing different linkers were prepared via acid–base reaction between the corresponding dicationic hydroxides and herbicides in the form of free acids. Additionally, the ionic liquids were fully characterized using NMR and thermal analysis. The herbicidal efficacy was tested during greenhouse experiments, using lambsquarters and oilseed rape as the test plants. In the case of determination of antifungal activity, six fungal species were used: Sclerotinia sclerotiorum, Botrytis cinerea, Fusarium culmorum, Fusarium oxysporum, Colletotrichum sp. and Monographella nivalis. The obtained results indicate that the conversion of compounds into dicationic ionic liquids affects their fungicidal and herbicidal activity. In the case of tests carried out on fungi, no difference in activity was observed at higher doses, except Monographella nivalis. However, at lower concentration (10 ppm), there is a reduction in efficacy compared to the reference substance. In addition, all obtained compounds are characterized by high activity.Graphic abstract

Optimization and Antifungal Activity Determination of Tea Tree Oil Containing Oxiconazole Loaded Ufasomes Gel Against Candida Albicans

Optimization and Antifungal Activity Determination of Tea Tree Oil Containing Oxiconazole Loaded Ufasomes Gel Against Candida Albicans

Phenolic extracts of cachaça aged in different woods and quantifying antioxidant activity and antifungal properties

The antioxidant and antifungal activities of the phenolic compounds in different alcoholic extracts of aged cachaca were evaluated. The physico-chemical analyses were performed in the Laboratorio de Qualidade de Aguardente of the Universidade Federal de Lavras according to the methods of the Ministerio Agricultura Pecuaria e abastecimento. Total phenol content was determined by the Folin–Ciocalteu method, quantification of these compounds was performed by HPLC and antioxidant activities were determined by methods involving inhibition of the DPPH (1,1-diphenyl-2 picrylhydrazyl) radical, the β-carotene/linoleic acid system, ABTS (2,2 azinobis-[3-ethyl-6-benzothiazolinesulfonic acid]) radical, reducing power and thiobarbituric acid. Determination of antifungal activity was accomplished through the technique of dissemination in discs using Aspergillus carbonarius, Aspergillus niger, Aspergillus flavus, Penicillium commune and Penicillium cladosporoides fungi at the Laboratorio de Micologia de Alimentos. The values obtained for the phenolic compounds ranged from 0.41 to 9.69 mg L−1; syringaldehyde, vanillic acid and gallic acid were predominant. A satisfactory antioxidant activity was observed in all of the tests with the alcoholic extracts. A moderate activity against P. commune and P. cladosporoides, but no inhibition of the growth of A. carbonarius, A. niger or A. flavus was observed. Copyright © 2016 The Institute of Brewing & Distilling

Bioassay-guided fractionation of extracts from Hypericum perforatum in vitro roots treated with carboxymethylchitosans and determination of antifungal activity against human fungal pathogens

The aim of this study was to individuate, by bioassay-guided fractionation, promising antifungal fractions and/or constituents from Hypericum perforatum subsp. angustifolium invitro roots. Treatments with chitosan, O-carboxymethylchitosan (CMC) and its derivatives were used to improve xanthone production in the roots. The bioassay-guided fractionation of CMC-treated roots led to the individuation of an ethyl acetate fraction, containing the highest amount of xanthones (6.8%) and showing the best antifungal activity with minimal inhibitory concentration (MIC) values of 53.82, 14.18, and 36.52μg/ml, against Candida spp., Cryptococcus neoformans and dermatophytes, respectively. From this fraction the prenylated xanthone, biyouxanthone D has been isolated and represented the 44.59% of all xanthones detected. For the first time in the present paper biyouxanthone D has been found in H.perforatum roots and tested against C.neoformans, dermatophytes, and Candida species. The xanthone showed the greatest antifungal activity against C.neoformans and dermatophytes, with MIC values of 20.16, 22.63μg/ml. In conclusion, the results obtained in the present study demonstrated that CMC-treated Hpa invitro root extracts represent a tool for the obtainment of promising candidates for further pharmacological and clinical studies.

Influence of capsule size on the in vitro activity of antifungal agents against clinical Cryptococcus neoformans var. grubii strains

Cryptococcosis causes disseminated disease in AIDS patients. In contrast to what occurs in laboratory conditions, a large capsule is produced by Cryptococcus neoformans in vivo during infection. The aim of this study was to compare the in vitro activity of different antifungal agents against 34 clinical isolates of C. neoformans var. grubii without or with capsule induction (CLSI, CLSI-C, respectively), following the CLSI M27A3 document. Capsule induction was obtained by addition of NaHCO(3) and incubation with CO(2). The geometric means of the MICs, in µg ml(-1), for CLSI and CLSI-C cultures, respectively, were 1.9 and 9.8 for fluconazole; 0.04 and 0.08 for itraconazole; 0.04 and 0.05 for voriconazole; 0.16 and 0.38 for amphotericin B; and 1.6 and 5.6 for 5-flucytosine. Thus fluconazole showed the highest MICs after capsule induction. Determination of antifungal activity after capsule induction may be clinically relevant and could be used to evaluate the correlation between in vitro results and clinical outcome.

Determination of Antifungal Activities in Serum Samples from Mice Treated with Different Antifungal Drugs Allows Detection of an Active Metabolite of Itraconazole

To establish an in vitro method of predicting in vivo efficacy of antifungal drugs against Candida albicans and Aspergillus fumigatus, the antifungal activities of fluconazole, itraconazole, and amphotericin B were determined in mouse serum. The minimum inhibitory concentration (MIC) of each drug was measured using mouse serum as a diluent. For C. albicans, the assay endpoint of azoles was defined as inhibition of mycelial extension (mMIC) and for A. fumigatus, as no growth (MIC). The MICs of amphotericin B for both pathogens were defined as the MIC at which no mycelial growth occurred. Serum MIC or mMIC determinations were then used to estimate the concentration of the drugs in serum of mice treated with antifungal drugs by multiplying the antifungal titer of the serum samples by the serum (m)MIC. The serum drug concentrations were also determined by HPLC. The serum concentrations estimated microbiologically showed good agreement with those determined by HPLC, except for itraconazole. Analysis of the serum samples from itraconazole-treated mice by a sensitive bioautography revealed the presence of additional spots, not seen in control samples of itraconazole. The bioautography assay demonstrated that the additional material detected in serum from mice treated with itraconazole was an active metabolite of itraconazole. The data showed that the apparent reduction in the itraconazole serum concentration as determined by HPLC was the result of the formation of an active metabolite, and that the use of a microbiological method to measure serum concentrations of drugs can provide a method for prediction of in vivo efficacy of antifungal drugs.

Conifer Seed Cone Proanthocyanidin Polymers: Characterization by 13C NMR Spectroscopy and Determination of Antifungal Activities

Proanthocyanidin polymers (condensed tannins) in extracts from Picea glauca, Pinus banksiana, Pinus nigra, Pinus ponderosa, and Pinus taeda seed cones were isolated by chromatography over Sephadex LH-20 and characterized by 13C nuclear magnetic resonance (NMR) spectroscopy. Ranging in molecular weight (MWn) from 1520 to 2460, the seed cone proanthocyanidins were comprised primarily of procyanidin monomer units with the 2,3-cis stereochemistry predominating in the heterocyclic rings. Incorporated into agar media, a proanthocyanidin polymer preparation inhibited the growth of fungal cultures of Ceratocystis coerulescens and Schizophyllum commune but not Trametes versicolor. However, under conditions more representative of those found in nature, the polymer preparation did impart significant decay resistance to T. versicolor in wood test specimens normally susceptible to decay by this fungus. It is apparent from these results that proanthocyanidin polymers contribute to the natural resistance of conifer seed cones to fungal degradation.

Salivary anti-candidal assays.

Inhibition of Candida albicans blastospore viability by parotid, submandibular-sublingual and whole salivas could not be determined by direct assay of yeast cells in each respective saliva. Determination of antifungal activity could, however, be carried out if saliva was first preincubated with Candida cells and this was immediately followed by removal of saliva and resuspension of yeast cells in nonenriched buffers of pH 5-7 for appropriate incubation periods. To attain accurate reproducible quantitative data, parotid, submandibular-sublingual and whole salivas each required different preincubation times with C. albicans as well as prior acidification and boiling. Acidification was also necessary for optimizing the germ tube assay although, in contrast to blastospore viability, inhibition of blastospore-germ tube conversion could be determined directly in saliva. Salivary antifungal effects on blastospore division were negligible at yeast cell concentrations greater than 10(6) colony-forming units per ml and were found to be independent of pH, whereas salivary inhibition of germ tube formation was significant only at pH 5 in the assay systems employed. The requirement for acidification and an observed enhancement of antifungal activity on aqueous dilution of the saliva suggested that only a fraction of the salivary antifungal components present in saliva were available in the free form to exert their biological activity. These results open up the possibility of investigating salivary antifungal activity in human health and disease.

Determination of Antifungal Activity of Some Organic Chemicals

Antifungal activity of four organic compounds was determined against fungi. Out of these m-chloronitrobenzene and 2, 3-dichloro-5, 6-dicyno- 1, 4-benzoquinone (DDQ) were found most effective at 250 ppm (0.025%), while p-chloroanaline and p-bromobenzene gave satisfactory results. In in vivo testing DDQ showed best results at 0.50 per cent concentration in fat liquor.