Antifungal Plant Defensins as an Alternative Tool to Combat Candidiasis.

Currently, the spread of fungal infections is becoming an urgent problem. Fungi of the Candida genus are opportunistic microorganisms that cause superficial and life-threatening systemic candidiasis in immunocompromised patients. The list of antifungal drugs for the treatment of candidiasis is very limited, while the prevalence of resistant strains is growing rapidly. Therefore, the search for new antimycotics, including those exhibiting immunomodulatory properties, is of great importance. Plenty of natural compounds with antifungal activities may be extremely useful in solving this problem. This review evaluates the features of natural antimicrobial peptides, namely plant defensins as possible prototypes of new anticandidal agents. Plant defensins are important components of the innate immune system, which provides the first line of defense against pathogens. The introduction presents a brief summary regarding pathogenic Candida species, the pathogenesis of candidiasis, and the mechanisms of antimycotic resistance. Then, the structural features of plant defensins, their anticandidal activities, their mechanisms of action on yeast-like fungi, their ability to prevent adhesion and biofilm formation, and their combined action with conventional antimycotics are described. The possible mechanisms of fungal resistance to plant defensins, their cytotoxic activity, and their effectiveness in in vivo experiments are also discussed. In addition, for the first time for plant defensins, knowledge about their immunomodulatory effects is also presented.

Anticandidal Activity of In Situ Methionine γ-Lyase-Based Thiosulfinate Generation System vs. Synthetic Thiosulfinates.

Candida albicans and non-albicans Candida species are a common cause of human mucosal infections, as well as bloodstream infections and deep mycoses. The emergence of resistance of Candida spp. to antifungal drugs used in practice requires the search for new antimycotics. The present study unravels the antifungal potential of the synthetic dialk(en)ylthiosulfinates in comparison with an enzymatic in situ methionine γ-lyase-based thiosulfinate generation system (TGS). The kinetics of the TGS reaction, namely, the methionine γ-lyase-catalyzed ß-elimination of S-alk(en)yl-L-cysteine sulfoxides, was investigated via 1H NMR spectroscopy for the first time, revealing fast conversion rates and the efficient production of anticandidal dialk(en)ylthiosulfinates. The anticandidal potential of this system vs. synthetic thiosulfinates was investigated through an in vitro assay. TGS proved to be more effective (MIC range 0.36-1.1 µg/mL) than individual substances (MIC range 0.69-3.31 µg/mL). The tested preparations had an additive effect with the commercial antimycotics fluconazole, amphotericin B and 5-flucytosine demonstrating a fractional inhibitory coefficient index in the range of 0.5-2 µg/mL. TGS can be regarded as an attractive candidate for the targeted delivery of antimycotic thiosulfinates and for further implementation onto medically implanted devices.

Development of Miconazole-Loaded Microemulsions for Enhanced Topical Delivery and Non-Destructive Analysis by Near-Infrared Spectroscopy.

The antifungal drug miconazole nitrate has a low solubility in water, leading to reduced therapeutic efficacy. To address this limitation, miconazole-loaded microemulsions were developed and assessed for topical skin delivery, prepared through spontaneous emulsification with oleic acid and water. The surfactant phase included a mixture of polyoxyethylene sorbitan monooleate (PSM) and various cosurfactants (ethanol, 2-(2-ethoxyethoxy) ethanol, or 2-propanol). The optimal miconazole-loaded microemulsion containing PSM and ethanol at a ratio of 1:1 showed a mean cumulative drug permeation of 87.6 ± 5.8 µg/cm2 across pig skin. The formulation exhibited higher cumulative permeation, permeation flux, and drug deposition than conventional cream and significantly increased the in vitro inhibition of Candida albicans compared with cream (p < 0.05). Over the course of a 3-month study conducted at a temperature of 30 ± 2 °C, the microemulsion exhibited favorable physicochemical stability. This outcome signifies its potential suitability as a carrier for effectively administering miconazole through topical administration. Additionally, a non-destructive technique employing near-infrared spectroscopy coupled with a partial least-squares regression (PLSR) model was developed to quantitatively analyze microemulsions containing miconazole nitrate. This approach eliminates the need for sample preparation. The optimal PLSR model was derived by utilizing orthogonal signal correction pretreated data with one latent factor. This model exhibited a remarkable R2 value of 0.9919 and a root mean square error of calibration of 0.0488. Consequently, this methodology holds potential for effectively monitoring the quantity of miconazole nitrate in various formulations, including both conventional and innovative ones.

Anticandidal activity of nanocomposite based on nanochitosan, nanostarch and mycosynthesized copper oxide nanoparticles against multidrug-resistant Candida.

Recently, antimicrobial resistance has increased globally particularly Candida infections. Most of antifungal drugs used for treating candidiasis became resistant to most of Candida species. In the current study, a nanocomposite based on mycosynthesized copper oxide nanoparticles (CuONPs), nanostarch, nanochitosan was prepared. Results illustrated that twenty-four Candida isolates were isolated from clinical samples. Furthermore, three Candida strains were selected as the most resistant among others toward commercial antifungal drugs; these selected strains were identified genetically as C. glabrata MTMA 19, C. glabrata MTMA 21 and C. tropicalis MTMA 24. Characterization of the prepared nanocomposite was carried out using physiochemical analysis included Ultraviolet-visible spectroscopy (Uv-Vis), Fourier-Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray spectroscopy (EDX) and Transmission Electron Microscopy (TEM). Moreover, the nanocomposite exhibited promising anticandidal activity against C. glabrata MTMA 19, C. glabrata MTMA 21 and C. tropicalis MTMA 24, where the inhibition zones were 15.3, 27 and 28 mm, respectively. Ultrastructure changes observed in nanocomposite-treated C. tropicalis demonstrated disruption of the cell wall which led to cell death. In conclusion, our results confirmed that the novel biosynthesized nanocomposite based on mycosynthesized CuONPs, nanostarch and nanochitosan is a promising anticandidal agent to fight multidrug-resistant Candida.

Lavandula angustifolia Essential Oils as Effective Enhancers of Fluconazole Antifungal Activity against Candida albicans.

The increasing prevalence of Candida albicans resistance to commercial antifungal agents in recent decades has prompted modern medicine and veterinary medicine to search for combined treatment options. The aim of the study was to determine the activity of essential oils from different cultivars and morphological parts of the medicinal lavender (Lavandula angustifolia) in combination with fluconazole against Candida albicans ATCC 10231 strain. The effect of the combination of lavender essential oil with fluconazole was tested using the checkerboard method, and the obtained results were interpreted on the basis of fractional inhibitory concentration indices (FICIs). A synergistic interaction was found for all combinations of fluconazole with essential oils isolated both from flowers and leafy stalks of two tested lavender cultivars: 'Blue River' and 'Ellagance Purple'. The observed enhancement effect of fluconazole antifungal activity was significantly stronger in the case of essential oils obtained from flowers and leafy stalks of 'Blue River' cultivar. Analogous studies were performed for linalool, one of the main components of lavender essential oils, and a similar synergistic interaction with fluconazole was found.

Synthesis of New Thiazole Derivatives Bearing Thiazolidin-4(5H)-One Structure and Evaluation of Their Antimicrobial Activity

The first report about antimicrobial resistance was published in the 1940s. And today, the antimicrobial resistance has become a worldwide problem. Because of this problem, there is a need to develop new drugs. That's why we synthesized some novel thiazolidine-4-one derivatives and evaluated their antimicrobial activity. The final compounds were obtained by reacting 2-[(4,5-diphenylthiazol-2-yl)imino]thiazolidin-4-one with some aryl aldehydes. The synthesized compounds were investigated for their antimicrobial activity against four Candida species, five gram-negative and four gram-positive bacterial species. The lead compounds (4a- h) were obtained with a yield of at least 70%. All compounds showed antimicrobial activity. Compound 4f (MIC: 31.25 µg/ml) exhibited more efficacy than the other compounds against C. glabrata (ATCC 24433). Compound 4b (MIC: 62.5 µg/ml) was the most active compound against all bacterial species, particularly K. pneumoniae (NCTC 9633). Whereas, compound 4c (MIC: <31.25 µg/ml) was observed as the most active compound against E. coli (ATCC 25922). In general, all compounds (4a-4h) showed antimicrobial activity against all fungi and bacterial species. Compounds 4b (2,6-dichlorobenzylidene), 4c (2,6-dihydroxybenzylidene), 4f (1H-pyrrol-2- yl)methylene), 4g (4-triflouromethylbenzylidene) and 4h (2,3,4-trimethoxybenzylidene) were determined as the most active compounds

The attenuation of antibiotic resistant non-albicans Candida species, cytotoxicity, anti-inflammatory effects and phytochemical profiles of five Vachellia species by FTIR and UHPLC-Q/Orbitrap/MS.

This work investigated the antifungal, cytotoxic and LPS-induced anti-inflammatory effects of five Vachellia species (V. karroo, V. kosiensis, V. sieberiana, V. tortalis and V. xanthophloea). The antifungal activity of the aqueous-methanolic extracts were performed using the broth dilution method against four non-albicans Candida species (C. glabrata, C. auris, C. tropicalis and C. parapsilosis). The cytotoxic and anti-inflammatory effects of the extracts were evaluated on African green monkey Vero kidney cells using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay and the 2',7'-dichlorofluorescin diacetate (H2DCF-DA) method. The fourier-transform infrared spectroscopy (FTIR) and Q Exactive plus orbitrap™ Ultra-high-performance liquid chromatography-mass spectrometer (UHPLC-MS) analysis was conducted to evaluate phytochemical constituents of the extracts. The plant extracts selected in this study displayed potency against the Candida species tested, with MIC values ≤0.62 mg/mL for V. karroo, V. kosiensis and V. xanthophloea. A dose-dependent cell viability was observed on Vero cells with all extracts showing LC50 values >20 µg/mL. Extracts tested at 10 µg/mL elicited a significant decrease in lipopolysaccharide (LPS)-induced reactive oxygen species (ROS) in Vero cells with V. sieberiana, V. tortilis, V. karroo, V. kosiensis and V. xanthophloea displaying inhibitory percentages of 35%, 32%, 55%, 52% and 49%, respectively. Characterisation of functional groups representing compounds in the extracts demonstrated the presence of different classes of compounds of the aliphatic, sugar and aromatic types. The Q Exactive plus orbitrap™ mass spectrometer enabled tentative identification of three major compounds in the extracts, including epigallocatechin, methyl gallate and quercetin amongst others. Based on the mass spectrometer results, it is postulated that quercetin found mostly in active extracts of V. karroo, V. xanthophloea, and V. kosiensis may be responsible for the observed antifungal and anti-inflammatory activity. This data demonstrates that the Vachellia species that were investigated could potentially be promising candidates for the management of fungal infections and related inflammation.

Synergistic Anticandidal Effects of Six Essential Oils in Combination with Fluconazole or Amphotericin B against Four Clinically Isolated Candida Strains.

The development of opportunistic pathogenic Candida strains insensitive to several classes of antifungals has emerged as a major health care problem during the last years. Combinational therapy of natural products (e.g., essential oils, EOs) with conventional antifungals has been suggested as a promising alternative to overcome this medical problem. The present study investigates the potential antifungal activity of EOs extracted from some selected medicinal plants, alone and in combination with two common conventional antifungals (fluconazole and amphotericin B) against four clinical Candida isolates. MIC assays indicated that EOs induced strong anticandidal activities with MIC values ranging from 0.162 to 4.950 mg/mL. The combination of amphotericin B with Thymus leptobotrys, Origanum compactum and Artemisia herba alba EOs provided a synergistic effect against C. krusei only, with MIC gain of four-fold, and additive effect against remaining strains (MIC gain = two-fold). Interesting synergistic interactions were observed by combining all studied EOs with fluconazole, with reduction rates of their MICs ranging from 16 to 512-fold. This synergistic effect was very pronounced with the combination of T. leptobotrys EO and fluconazole. These findings indicate that studied EOs can be used as anti-candidals in combination with antifungals, particularly fluconazole, to counteract the emergence of resistant Candida spp.

Design, Synthesis and Anticandidal Evaluation of Indazole and Pyrazole Derivatives.

Candidiasis, caused by yeasts of the genus Candida, is the second cause of superficial and mucosal infections and the fourth cause of bloodstream infections. Although some antifungal drugs to treat candidiasis are available, resistant strains to current therapies are emerging. Therefore, the search for new candicidal compounds is certainly a priority. In this regard, a series of indazole and pyrazole derivatives were designed in this work, employing bioisosteric replacement, homologation, and molecular simplification as new anticandidal agents. Compounds were synthesized and evaluated against C. albicans, C. glabrata, and C. tropicalis strains. The series of 3-phenyl-1H-indazole moiety (10a-i) demonstrated to have the best broad anticandidal activity. Particularly, compound 10g, with N,N-diethylcarboxamide substituent, was the most active against C. albicans and both miconazole susceptible and resistant C. glabrata species. Therefore, the 3-phenyl-1H-indazole scaffold represents an opportunity for the development of new anticandidal agents with a new chemotype.

In vitro anticandidal activity and gas chromatography-mass spectrometry (GC-MS) screening of Vitex agnus-castus leaf extracts.

BACKGROUND: Candida infections are becoming more drug resistant; it is necessary to search for alternative medications to treat them. Therefore, the present study estimates the anticandidal activity of Vitex agnus-castus (VA-C) leaf extracts. METHODS: We used the agar well diffusion method to assess the anticandidal activity of three different VA-C leaf extracts (ethanol, methanol, and water) against three Candida species (Candida tropicalis, Candida albicans, and Candida ciferrii). The minimum inhibitory concentration (MIC) was estimated using the two-fold dilution method and the minimum fungicidal concentration (MFC) was determined using the classic pour plate technique. The MFC/MIC ratio was calculated to estimate the microbicidal or microbiostatic activity. A gas chromatography mass spectrometer was used to screen the phytochemicals of the VA-C leaf extracts (ethanol, methanol, and water). RESULTS: All VA-C extracts ethanol, methanol, and water were significantly inhibited the growth of the test Candida species and the inhibition activity depended on the solvent used and the Candida species. The results showed that C. tropicalis was the most highly inhibited by all extracts followed by C. albicans and C. ciferrii. The MIC values were 12.5-25 µg/ml, and MFC values were 25-100 µg/ml. The ratios of MFC/MIC were two-fold to four-fold which was considered candidacidal activity. Ninety-five phytochemical compounds were identified by the GC-MS assay for the VA-C leaf extracts. The total number of compounds per extract differed. Methanol had 43 compounds, ethanol had 47 compounds, and water had 52 compounds. The highest compound concentrations were: 4,5-Dichloro-1,3-dioxolan-2-one in ethanol and methanol, 1H-Indene, 2,3-dihydro-1,1,2,3,3-pentamethyl in ethanol, Isobutyl 4-hydroxybenzoate in methanol, and Benzoic acid and 4-hydroxy- in water. These phytochemical compounds belong to different bioactive chemical group such as polyphenols, fatty acids, terpenes, terpenoids, steroids, aldehydes, alcohols, and esters, and most of which have anticandidal activity. CONCLUSIONS: VA-C leaf extracts may be useful alternatives to anticandidal drugs, based on their effectiveness against all test Candida species at low concentrations. However, appropriate toxicology screening should be conducted before use.

Anticandidal formyl phloroglucinol meroterpenoids: Biomimetic synthesis and in vitro evaluation.

Inspired by the diversity-oriented synthesis, some novel formyl phloroglucinol meroterpenoids were synthesized via biomimetic synthesis using essential oils. Eight of them were demonstrated with good in vitro fungicidal activity against Candida albicans and C. glabrata. Compound c2 showed the best anticandidal ability that was powerfully comparable to fluconazole when testing against several strains in vitro. The antibiofilm activity was also found for the c2 treating group which was evidenced to block the hyphal elongation and filamentation of C. albicans. Therefore, compound c2 is a promising candidate for further antifungal-based structure modification.

Phytol-Loaded Solid Lipid Nanoparticles as a Novel Anticandidal Nanobiotechnological Approach.

Phytol is a diterpene alcohol and can be found as a product of the metabolism of chlorophyll in plants. This compound has been explored as a potential antimicrobial agent, but it is insoluble in water. In this study, we describe a novel approach for an interesting anticandidal drug delivery system containing phytol. Different formulations of phytol-loaded solid lipid nanoparticles (SLN) were designed and tested using a natural lipid, 1,3-distearyl-2-oleyl-glycerol (TG1). Different compositions were considered to obtain three formulations with 1:10, 1:5, and 1:3 w/w phytol/TG1 ratios. All the formulations were prepared by emulsification solvent evaporation method and had their physicochemical properties assessed. The biocompatibility assay was performed in the HEK-293 cell line and the antifungal efficacy was demonstrated in different strains of Candida ssp., including different clinical isolates. Spherical and uniform SLN (<300 nm, PdI < 0.2) with phytol-loading efficiency >65% were achieved. Phytol-loaded SLN showed a dose-dependent cytotoxic effect in the HEK-293 cell line. The three tested formulations of phytol-loaded SLN considerably enhanced the minimal inhibitory concentration of phytol against 15 strains of Candida spp. Considering the clinical isolates, the formulations containing the highest phytol/TG1 ratios showed MICs at 100%. Thus, the feasibility and potential of phytol-loaded SLN was demonstrated in vitro, being a promising nanocarrier for phytol delivery from an anticandidal approach.

Octominin: A Novel Synthetic Anticandidal Peptide Derived from Defense Protein of Octopus minor.

: The rapid emergence of multidrug-resistant pathogens makes an urgent need for discovering novel antimicrobial agents as alternatives to conventional antibiotics. Towards this end, we designed and synthesized a synthetic peptide of 23 amino acids (AAs) (1GWLIRGAIHAGKAIHGLIHRRRH23) from a defense protein 3 cDNA sequence of Octopus minor. The sequence of the peptide, which was named Octominin, had characteristic features of known antimicrobial peptides (AMPs) such as a positive charge (+5), high hydrophobic residue ratio (43%), and 1.86 kcal/mol of Boman index. Octominin was predicted to have an alpha-helix secondary structure. The synthesized Octominin was 2625.2 Da with 92.5% purity. The peptide showed a minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of 50 and 200 µg/mL, respectively, against Candida albicans. Field emission scanning electron microscopy observation confirmed that Octominin caused ultrastructural cell wall deformities in C. albicans. In addition, propidium iodide penetrated the Octominin-treated C. albicans cells, further demonstrating loss of cell membrane integrity that caused cell death at both MIC and MFC. Octominin treatment increased the production of intracellular reactive oxygen species and decreased cell viability in a concentration dependent manner. Cytotoxicity assays revealed no significant influence of Octominin on the viability of human embryonic kidney 293T cell line, with over 95% live cells in the Octominin-treated group observed up to 100 µg/mL. Moreover, we confirmed the antifungal action of Octominin in vivo using a zebrafish experimental infection model. Overall, our results demonstrate the Octominin is a lead compound for further studies, which exerts its effects by inducing cell wall damage, causing loss of cell membrane integrity, and elevating oxidative stress.

Antimicrobial activity and chemical composition of essential oil from Helichrysum microphyllum Cambess. subsp. tyrrhenicum Bacch., Brullo & Giusso collected in South-West Sardinia.

The aim of this study was to evaluate the chemical composition and the antimicrobial activity of essential oils of Helichrysum microphyllum subsp. tyrrhenicum collected in four different stations in South-Western Sardinia. The composition of the essential oils was determined by gas chromatography and gas chromatography/mass spectrometry. The oil samples showed different chromatographic profiles. The oil of the station 4 revealed the presence of significant amount of neryl acetate (33.6%); in oils from stations 1 and 2 we found γ-curcumene (28%) and in station 3 γ-curcumene (12%) and linalool (11%), while there was no trace of neryl acetate. Standard microbiological assays demonstrated that essential oils obtained by plants collected in station 1 and 2, very rich in curcumene, showed an interesting anticandidal activity, dose- and time-dependent, which is enhanced by sub-inhibitory concentrations of chitosan. Our results suggest that the essential oil of Helichrysum microphyllum subsp. tyrrhenicum, associated with chitosan in innovative formulations, could be considered as a therapeutic alternative in the treatment of Candida opportunistic infections. The results of this study shows that the chemotypization of the species examined could lead to their targeted clinical use, in a concept of a rational scientific aromatherapy.

Effect of Clove and Thyme Essential Oils on Candida Biofilm Formation and the Oil Distribution in Yeast Cells.

Candida biofilm structure is particularly difficult to eradicate, since biofilm is much more resistant to antifungal agents than planktonic cells. In this context, a more effective strategy seems to be the prevention of biofilm formation than its eradication. The aim of the study was to examine whether the process of initial colonization of materials (glass, polyethylene terephthalate, polypropylene) by food-borne Candida sp. can be impeded by clove and thyme essential oils, used at their minimal inhibitory concentrations. In the presence of clove oil, 68.4-84.2% of the yeast tested showed a statistically significant reduction in biofilm formation, depending on the material. After treatment with thyme oil, statistically significant decrease in biofilm cell numbers was observed for 63.2-73.7% of yeasts. Confocal laser scanning microscopy showed diverse compounds of clove and thyme oils that were disparately located in C. albicans cell, on a cell wall and a cell membrane, in cytoplasm, and in vacuoles, depicting the multidirectional action of essential oils. However, essential oils that were used in sub-inhibitory concentration were sequestrated in the yeast vacuoles, which indicate the activation of Candida defense mechanisms by cell detoxification. Clove and thyme essential oils due to their anti-biofilm activity can be efficiently used in the prevention of the tested abiotic surfaces colonization by Candida sp.

Anticandidal activities of lactic acid bacteria isolated from the vagina

Background/aim: Lactic acid bacteria prevent the overgrowth of pathogenic agents and opportunistic pathogens in the vagina. Moreover, lactic acid bacteria contribute to the preservation of vaginal microbiota by producing antimicrobial agents. Previous studies showed that some lactic acid bacteria exhibited antimicrobial activity against Candida species causing yeast vaginosis as well as many bacterial pathogens. Materials and methods: The antifungal activities of various lactic acid bacteria isolated from the vagina of healthy women on some Candida species isolated from the vagina were investigated by agar diffusion technique. Results: Most of the lactic acid bacteria that belong to the species of Lactobacillus crispatus, L. fermentum, L. acidophilus, L. paracesei subsp. paracesei, L. pentosus, and L. plantarum exhibited antifungal activity in varying ratios against C. albicans, C. glabrata, and C. tropicalis strains isolated from the vagina. Conclusion: The lactic acid bacteria are useful microorganisms associated with a variety of probiotic properties. In this sense, our lactic acid bacteria isolates with high antifungal activity may be promising candidates as probiotic microorganisms in the inhibition of vaginal candidiasis, which is one of the most prevalent problems, or in the protection against candidiasis. We will continue our studies in this area.

Antifungal Activity Directed Toward the Cell Wall by 2-Cyclohexylidenhydrazo- 4-Phenyl-Thiazole Against Candida albicans.

BACKGROUND: The increasing incidence of invasive forms of candidiasis and resistance to antifungal therapy leads us to seek new and more effective antifungal compounds. OBJECTIVE: To investigate the antifungal activity and toxicity as well as to evaluate the potential targets of 2- cyclohexylidenhydrazo-4-phenyl-thiazole (CPT) in Candida albicans. METHODS: The antifungal activity of CPT against the survival of C. albicans was investigated in Caenorhabditis elegans. Additionally, we determined the effect of CPT on the inhibition of C. albicans adhesion capacity to buccal epithelial cells (BECs), the toxicity of CPT in mammalian cells, and the potential targets of CPT in C. albicans. RESULTS: CPT exhibited a minimum inhibitory concentration (MIC) value of 0.4-1.9 µg/mL. Furthermore, CPT at high concentrations (>60 x MIC) showed no or low toxicity in HepG2 cells and <1% haemolysis in human erythrocytes. In addition, CPT decreased the adhesion capacity of yeasts to the BECs and prolonged the survival of C. elegans infected with C. albicans. Analysis of CPT-treated cells showed that their cell wall was thinner than that of untreated cells, especially the glucan layer. We found that there was a significantly lower quantity of 1,3-ß-D-glucan present in CPT-treated cells than that in untreated cells. Assays performed on several mutant strains showed that the MIC value of CPT was high for its antifungal activity on yeasts with defective 1,3-ß-glucan synthase. CONCLUSION: In conclusion, CPT appears to target the cell wall of C. albicans, exhibits low toxicity in mammalian cells, and prolongs the survival of C. elegans infected with C. albicans.

Isolation, identification and anti-candidal activity of filamentous fungi from Saudi Arabia soil.

Ten fungal strains; namely, Penicillium melinii, Petriella setifera, Aspergillus pseudo-niger, Alternaria chlamydospora, Pythium nayoroense, Phoma glomerata, Mucor ramosissimus, Mucor racemosus, Fusarium chlamydosporum and Rhizopus azygosporus were isolated from soil. The extra- and intra-cellular extracts of the fungal strains grown on malt extract and yeast-extract sucrose media were screened for their anticandidal activity against different clinically-isolated Candida species. Most of the fungal extracts showed activity against different Candida species. However, the fungal strains grew on malt extract showed greater activities than those grew on yeast extract sucrose media. The activity of the intracellular was higher than the extracellular metabolites. All fungal extracts (extra and intra) were similar in chemical constituent; they contained carbohydrates and/or glycosides, unsaturated sterols and/or triterpens, tannins and traces of coumarins. Alkaloids, flavonoids, saponins, anthraquinones and cardenolides were no detected. The intra-cellular extracts contained more compounds than the extra-cellular extracts.

Synthesis and Anticandidal Activity of New Imidazole-Chalcones.

In the present work, 15 new 1-(4-(1H-imidazol-1-yl)phenyl)-3-(4-substituedphenyl)prop-2-en-1-one derivatives (3a−3o) were synthesized to evaluate their antifungal activity. Structures of newly synthesized imidazole derivatives (3a−3o) were characterized by IR, ¹H-NMR, 13C-NMR, and LCMSMS spectroscopic methods. The anticandidal activity of compounds (3a−3o) against C. albicans (ATCC 24433), C. krusei (ATCC 6258), C. parapsilosis (ATCC 22019), and C. glabrata (ATCC 90030) was elucidated according to the EUCAST definitive (EDef 7.1) method. Consistent with the activity studies, 3a−3d were found to be more potent derivatives with their MIC50 values (0.78 µg/mL−3.125 µg/mL) against Candida strains. Compound 3c indicated similar antifungal activity to ketoconazole against all Candida species and was evaluated as the most active derivative in the series. Effects of the most potent derivatives 3a−3d on ergosterol biosynthesis were observed by LC-MS-MS method, which is based on quantification of the ergosterol level in C. krusei. Moreover, these compounds were subjected to a cytotoxicity test for the preliminary toxicological profiles and were found as non-cytotoxic. Furthermore, docking studies for the most active derivative 3c were performed to evaluate its binding modes on lanosterol 14-α-demethylase. In addition to in vitro tests, docking studies also revealed that Compound 3c is a potential ergosterol biosynthesis inhibitor.

Green Synthesis of Silver Nanoparticles Using Leaf Extract of Common Arrowhead Houseplant and Its Anticandidal Activity.

BACKGROUND: Silver nanoparticles have excellent medical and nonmedical properties and application compared with other metallic nanoparticles. In the present study, fresh leaves of Syngonium podophyllum have been used for synthesis of silver nanoparticles. OBJECTIVES: In this study, we evaluated the anticandidal activity of S. podophyllum and the synthesized nanoparticles. MATERIALS AND METHODS: In this study, simple and economical procedure was adopted for silver nanoparticles synthesis. S. podophyllum leaf was processed to obtain aqueous extract as a biological material for nanoparticles production. Synthesized nanoparticles were characterized by ultraviolet (UV) spectroscopy, X-ray diffraction (XRD), and atomic force microscopy. RESULTS: The progress of silver nanoparticles biosynthesis from leaf extract of S. podophyllum was observed by UV-visible spectroscopy. The peaks maxima were observed at 455 nm for silver nanoparticles synthesized from the leaf extracts of S. podophyllum. XRD diffractogram showing Bragg peaks of face-centered cubic crystalline elemental silver confirming the formation of silver nanoparticles. The minimal inhibitory concentration values of aqueous extracts of S. podophyllum leaf were estimated by broth dilution method and found that the extracts exhibited antifungal activity against Candida albicans. The antifungal activity was also determined using disk diffusion method by measuring the diameter for zone of inhibition. CONCLUSION: S. podophyllum leaf extract shows strong antifungal activity against C. albicans. S. podophyllum could be applied in the fields of medical and pharmaceuticals for formulation of new drugs. SUMMARY: The synthesis, characterization, and antifungal activities of silver nanoparticle from Common arrowhead house plant.The silver nanoparticles were confirmed to be spherical in shape.The antifungal activities of the confirmed their therapeutic potential. Abbreviation used: AgNO3: Silver nitrate, MIC: Minimum inhibitory concentration, MTCC: Microbial type culture collection, SPR: Surface plasmon resonance, UV: Ultraviolet, XRD: X-ray diffraction.