Identification and characterization of silver nanoparticles from Erythrina indica and its antioxidant and Uropathogenic antimicrobial properties.

The plant Erythrina indica comes under Fabaceae family, mainly used for used in traditional medicine as nervine sedative, antiepileptic, antiasthmatic, collyrium in opthalmia, antiseptic. Current study focused synthesize of silver nanoparticles (AgNPs) by E. indica leaf ethanol extract. The green-synthesized AgNPs underwent characterization using multiple analytical techniques, including UV-visible, FTIR, DLS, SEM, TEM, XRD, and EDX, and estimation of their antioxidant activity and antimicrobial activity. Phytochemical analysis identified alkaloids, tannins, saponins, flavonoids, and phenols as secondary metabolites. The Total Phenol Content (TPC) was determined to be 237.35 ± 2.02 mg GAE-1, indicating a substantial presence of phenolic compounds. The presence of AgNPs was verified through UV-Visible analysis at 420 nm, and FT-IR revealed characteristic phenolic functional groups. DLS analysis indicated a narrow size distribution (polydispersity index - PDI: 3.47%), with SEM revealing spherical AgNPs of approximately 20 nm. TEM showed homogeneous, highly polycrystalline AgNPs with lattice spacing at 0.297. XRD analysis demonstrated crystallinity and purity, with distinct reflection peaks corresponding to miller indices of JCPDS card no. 01 087 1473. In vitro, AgNPs exhibited robust antioxidant activity like; DPPH, ABTS, and H2O2, surpassing E. indica-assisted synthesis. ABTS assay indicated higher antioxidant activity (81.94 ± 0.05%) for AgNPs at 734 nm, while E. indica extraction showed 39.67 ± 0.07%. At 532 nm, both E. indica extraction (57.71 ± 0.11%) and AgNPs (37.41 ± 0.17%) exhibited H2O2 scavenging. Furthermore, AgNPs displayed significant antimicrobial properties, inhibiting Staphylococcus aureus (15.7 ± 0.12 mm) and Candida albicans (10.7 ± 0.17 mm) byfor the concentration of 80 µg/mL. Through the characterizations underscore of the potential of Erythrina indica-synthesized AgNPs, rich in polyphenolic compounds, for pharmacological, medical, biological applications and antipyretic properties.

Seriphidium herba-alba (Asso): A comprehensive study of essential oils, extracts, and their antimicrobial properties.

Seriphidium herba-alba (Asso), a plant celebrated for its therapeutic qualities, is widely used in traditional medicinal practices throughout the Middle East and North Africa. In a detailed study of Seriphidium herba-alba (Asso), essential oils and extracts were analyzed for their chemical composition and antimicrobial properties. The essential oil, characterized using mass spectrometry and retention index methods, revealed a complex blend of 52 compounds, with santolina alcohol, α-thujone, ß-thujone, and chrysanthenone as major constituents. Extraction yields varied significantly, depending on the plant part and method used; notably, methanol soaking of aerial parts yielded the most extract at 17.75%. The antimicrobial analysis showed that the extracts had selective antibacterial activity, particularly against Staphylococcus aureus, and broad-spectrum antifungal activity against organisms such as Candida albicans and Aspergillus spp. The methanol-soaked extract demonstrated the strongest antimicrobial properties, indicating its potential as a natural antimicrobial source. This study not only underscores the therapeutic potential of Seriphidium herba-alba (Asso) in pharmaceutical applications but also sets a foundation for future research focused on isolating specific bioactive compounds and in vivo testing.

Effect of Pulsatilla decoction on vulvovaginal candidiasis in mice. Evidences for its mechanisms of action.

BACKGROUND: Vulvovaginal candidiasis (VVC) is a common infection that affects the female reproductive tract. Pulsatilla decoction (PD), a traditional Chinese herbal medicine, is a classic and effective prescription for VVC. However, its mechanism of action remains unclear. PURPOSE: This study aimed to evaluate the efficacy and potential mechanism of action of the n-butanol extract of Pulsatilla decoction (BEPD) in VVC treatment. METHODS: High performance liquid chromatography (HPLC) was used to detect the main active ingredients in BEPD. A VVC-mouse model was constructed using an estrogen-dependent method to evaluate the efficacy of BEPD in VVC treatment. Fungal burden and morphology in the vaginal cavity were comprehensively assessed. Candida albicans-induced inflammation was examined in vivo and in vitro. The effects of BEPD on the Protein kinase Cδ (PKCδ) /NLR family CARD domain-containing protein 4 (NLRC4)/Interleukin-1 receptor antagonist (IL-1Ra) axis were analyzed using by immunohistochemistry (IHC), immunofluorescence (IF), western blot (WB), and reverse transcription-quantitative polymerase chain reaction (qRT-PCR). RESULTS: BEPD inhibited fungal growth in the vagina of VVC mice, preserved the integrity of the vaginal mucosa, and suppressed inflammatory responses. Most importantly, BEPD activated the "silent" PKCδ/NLRC4/IL-1Ra axis and negatively regulated NOD-like receptor thermal protein domain associated protein 3 (NLRP3) inflammasome, thereby exerting a therapeutic efficacy on VVC. CONCLUSIONS: BEPD effects on mice with VVC were dose-dependent. BEPD protects against VVC by inhibiting inflammatory response and NLRP3 inflammasome via the activation of the PKCδ/NLRC4/IL-1Ra axis. This study revealed the pharmacological mechanism of BEPD in VVC treatment and provided further evidence for the application of BEPD in VVC treatment.

Insights into the anti-Candida albicans properties of natural phytochemicals: An in vitro and in vivo investigation.

Invasive candidiasis, attributed to Candida albicans, has long been a formidable threat to human health. Despite the advent of effective therapeutics in recent decades, the mortality rate in affected patient populations remains discouraging. This is exacerbated by the emergence of multidrug resistance, significantly limiting the utility of conventional antifungals. Consequently, researchers are compelled to continuously explore novel solutions. Natural phytochemicals present a potential adjunct to the existing arsenal of agents. Previous studies have substantiated the efficacy of phytochemicals against C. albicans. Emerging evidence also underscores the promising application of phytochemicals in the realm of antifungal treatment. This review systematically delineates the inhibitory activity of phytochemicals, both in monotherapy and combination therapy, against C. albicans in both in vivo and in vitro settings. Moreover, it elucidates the mechanisms underpinning the antifungal properties, encompassing (i) cell wall and plasma membrane damage, (ii) inhibition of efflux pumps, (iii) induction of mitochondrial dysfunction, and (iv) inhibition of virulence factors. Subsequently, the review introduces the substantial potential of nanotechnology and photodynamic technology in enhancing the bioavailability of phytochemicals. Lastly, it discusses current limitations and outlines future research priorities, emphasizing the need for high-quality research to comprehensively establish the clinical efficacy and safety of phytochemicals in treating fungal infections. This review aims to inspire further contemplation and recommendations for the effective integration of natural phytochemicals in the development of new medicines for patients afflicted with C. albicans.

Candida albicans Infections: a novel porcine wound model to evaluate treatment efficacy.

Candida albicans is a common cause of opportunistic mycoses worldwide and a major contributor in wound infections. The purpose of this study was to establish a fungal wound model and analyze the effects of a common antifungal agent against the proliferation of three C. albicans strains. Second degree burns were created, and then inoculated with one of three different C. albicans ATCC strains: 10261 reference strain, 64550 fluconazole resistant and 26310 fluconazole sensitive. After fungal inoculation, every wound was covered with dressings for 4 h to allow fungal colonization on every wound bed. After 4 h, the dressings were removed, and each wound was treated either once or twice daily with a topical terbinafine hydrochloride or left untreated. On days 2, 4 and 7 post inoculation, three wounds from each treatment group were scrub cultured and quantified. On day 2, wounds infected with the sensitive strains 26310 and 10261 and treated twice showed a significant reduction when compared against those infected wounds receiving once daily treatment. On day 4, wounds which were infected with C. albicans fluconazole sensitive (ATCC 26310) showed a significant reduction in fungal cell counts with treatment applied twice daily. A significant reduction in the colony counts was exhibited in all three strains at the seventh day with active as compared to the non-treated wounds. Twice daily treatment resulted in a lower fungal count than once daily treatment. Neither treatment was able to entirely eradicate C. albicans during the duration of this study. Establishing a reliable fungal wound model will help in the translational goal of identifying new antifungal that could be used clinically by wound care providers.

Antifungal and Anti-Virulent Activity of Origanum majorana L. Essential Oil on Candida albicans and In Vivo Toxicity in the Galleria mellonella Larval Model.

The aim of this study was to investigate and compare in detail both the antifungal activity in vitro (with planktonic and biofilm-forming cells) and the essential oil composition (EOs) of naturally growing (OMN) and cultivated (OMC) samples of Origanum majorana L. (marjoram). The essential oil composition was analyzed using GC-MS. The major constituent of both EOs was carvacrol: 75.3% and 84%, respectively. Both essential oils showed high antifungal activity against clinically relevant Candida spp. with IC50 and IC90 less than or equal to 0.5 µg mL-1 and inhibition of biofilm with a concentration of 3.5 µg mL-1 or less. Cultivated marjoram oil showed higher anti-biofilm activity against C. albicans. In addition, OMC showed greater inhibition of germ-tube formation (inhibition by 83% in Spider media), the major virulence factor of C. albicans at a concentration of 0.125 µg mL-1. Both EOs modulated cell surface hydrophobicity (CSH), but OMN proved to be more active with a CSH% up to 58.41%. The efficacy of O. majorana EOs was also investigated using Galleria mellonella larvae as a model. It was observed that while the larvae of the control group infected with C. albicans (6.0 × 108 cells) and not receiving treatment died in the controls carried out after 24 h, all larvae in the infected treatment group survived at the end of the 96th hour. When the treatment group and the infected group were evaluated in terms of vital activities, it was found that the difference was statistically significant (p < 0.001). The infection of larvae with C. albicans and the effects of O. majorana EOs on the hemocytes of the model organism and the blastospores of C. albicans were evaluated by light microscopy on slides stained with Giemsa. Cytological examination in the treatment group revealed that C. albicans blastospores were phagocytosed and morphological changes occurred in hemocytes. Our results indicated that the essential oil of both samples showed strong antifungal activities against planktonic and biofilm-forming C. albicans cells and also had an influence on putative virulence factors (germ-tube formation and its length and on CSH).

Novel Antifungal Dimers from the Roots of Taiwania cryptomerioides.

Five new dimer compounds, namely Taiwaniacryptodimers A-E (1-5), were isolated from the methanol extract of the roots of Taiwania cryptomerioides. Their structures were established by mean of spectroscopic analysis and comparison of NMR data with those of known analogues. Their antifungal activities were also evaluated. Our results indicated that metabolites 1, 2, 4, and 5 displayed moderate antifungal activities against Aspergillus niger, Penicillium italicum, Candida albicans, and Saccharomyces cerevisiae.

Paeonol enhances treatment of fluconazole and amphotericin B against oropharyngeal candidiasis through HIF-1α related IL-17 signaling.

Oropharyngeal candidiasis (OPC) is an oral infection mainly caused by Candida albicans, a dimorphic human opportunistic pathogen that can proliferate and invade the superficial oral epithelium using its hyphae. The filamentation of C. albicans is a hallmark of biofilm formation, accompanied by the occurrence of a hypoxic microenvironment. Paeonol (PAE) is a traditional medicine with multiple properties. In a previous study, we demonstrated the synergism of PAE plus Fluconazole (FLU) or Amphotericin B (AmB) against C. albicans in vitro and in vivo. This study aimed to explore the therapeutic mechanisms of drug combinations on OPC. In an established OPC mouse model, the culture of hypoxia was observed by calcofluor white and hypoxyprobe staining. The expression and levels of IL-17 signaling-associated genes and proteins (IL-17A and IL-23) were evaluated in tissue homogenates and EC109 cells. The results show that compared with the single therapy, PAE plus FLU or AmB can decrease fungal burden, restore mucosal integrity, and reduce the hypoxic microenvironment and inflammation in the OPC mice. Relative to infected mice, the drug combinations can also rectify the abnormal expression of hypoxia inducible factor (hif)-1α, il-17a, and il-23 mRNA. Meanwhile, compared with the infected EC109 cells treated with a single drug, PAE plus FLU or AmB significantly inhibited the mRNA and protein expression of HIF-1α, IL-17A, and IL-23. Taken together, the possible mechanism of PAE plus FLU or AmB can be attributed to the regulation of hypoxia-associated IL-17 signaling in OPC treatment.

Development, optimization, and evaluation of a nanostructured lipid carrier of sesame oil loaded with miconazole for the treatment of oral candidiasis.

Candida albicans is the fungus responsible for oral candidiasis, a prevalent disease. The development of antifungal-based delivery systems has always been a major challenge for researchers. This study was designed to develop a nanostructured lipid carrier (NLC) of sesame oil (SO) loaded with miconazole (MZ) that could overcome the solubility problems of MZ and enhance its antifungal activity against oral candidiasis. In the formulation of this study, SO was used as a component of a liquid lipid that showed an improved antifungal effect of MZ. An optimized MZ-loaded NLC of SO (MZ-SO NLC) was used, based on a central composite design-based experimental design; the particle size, dissolution efficiency, and inhibition zone against oral candidiasis were chosen as dependent variables. A software analysis provided an optimized MZ-SO NLC with a particle size of 92 nm, dissolution efficiency of 88%, and inhibition zone of 29 mm. Concurrently, the ex vivo permeation rate of the sheep buccal mucosa was shown to be significantly (p < .05) higher for MZ-SO NLC (1472 µg/cm2) as compared with a marketed MZ formulation (1215 µg/cm2) and an aqueous MZ suspension (470 µg/cm2). Additionally, an in vivo efficacy study in terms of the ulcer index against C. albicans found a superior result for the optimized MZ-SO NLC (0.5 ± 0.50) in a treated group of animals. Hence, it can be concluded that MZ, through an optimized NLC of SO, can treat candidiasis effectively by inhibiting the growth of C. albicans.

Estudio comparativo de la actividad anti-fúngica de extractos secuenciales de Fuchsia lycioides contra Candida sp / comparative study of the antifungal activity of sequencial extracts of Fuchsia lycioides against Candida sp

The genus Fuchsia is generally used in herbal preparations to treat conditions caused by microorganisms. Based on the popular use of this type of plants, the objective of this study was to obtain sequential extracts of increasing polarity from the branches of Fuchsia lycioides by maceration at room temperature and by the Soxhlet method at 60ºC, to later evaluate the antifungal capacity of the extracts against different clinical isolates of the Candida genus. The ethyl acetate extract exhibited strong anti-fungal activity, selectively inhibiting C. albicans strains with MIC and CMF values of 10 and 15 µg/mL, respectively; comparable with the drug itraconazole®. The analysis of the extract by GC-MS showed a high concentration of terpenoids (mainly phytol) and phenylpropanoids (mainly cinnamic acid), possibly responsible for the antifungal activity of the ethyl acetate extract of F. lycioides.

El género Fuchsia se usa generalmente en preparaciones de hierbas para tratar afecciones provocadas por microorganismos. En base al uso popular de este tipo de plantas, el objetivo de este estudio fue obtener los extractos secuenciales de polaridad creciente de las ramas de Fuchsia lycioides por maceración a temperatura ambiente y por el método Soxhlet a 60ºC, para luego evaluar la capacidad antifúngica de los extractos frente a diferentes aislados clínicos del genero Candida. El extracto de acetato de etilo exhibió una fuerte actividad antifúngica inhibiendo en forma selectiva las cepas de C. albicans con valores de CMI y de CMF de 10 y 15 µg/mL, respectivamente; comparables con el fármaco itraconazol®. El análisis del extracto por CG-EM mostró una alta concentración de terpenoides (principalmente fitol) y fenilpropanoides (principalmente ácido cinámico), posibles responsables de la actividad antifúngica del extracto de acetato de etilo de F. lycioides.

Heat shock protein 90 (Hsp90)/Histone deacetylase (HDAC) dual inhibitors for the treatment of azoles-resistant Candida albicans.

Clinical treatment of candidiasis has suffered from increasingly severe drug resistance and limited efficacy. Thus, novel strategies to deal with drug resistance are highly desired to develop effective therapeutic agents. Herein, dual inhibition of heat shock protein 90 (Hsp90) and histone deacetylase (HDAC) was validated as a new strategy to potentiate efficacy of fluconazole against resistant Candida albicans infections. The first generation of Hsp90/HDAC dual inhibitors were designed as synergistic enhancers to treat azoles-resistant candidiasis. In particular, compound J5 exhibited fungal-selective inhibitory effects on Hsp90 and HDACs, leading to low toxicity and excellent in vitro (FICI = 0.266) and in vivo synergistic antifungal potency to treat fluconazole resistant candidiasis. Antifungal-mechanistic investigation revealed that compound J5 suppressed important virulence factors and down-regulated expression of resistance-associated genes. Therefore, Hsp90/HDAC dual inhibitors represent a new strategy for the development of novel antifungal therapeutics to combat azole-resistant candidiasis.

Chlorinated bisabolene sesquiterpenoids from the whole plant of Parasenecio rubescens.

Four new chlorinated bisabolene-type sesquiterpenoids (1-4) were isolated during the phytochemical investigation of an acetone extract of the whole plant of Parasenecio rubescens. The structures of 1-4 were determined by analysis of their HRESIMS and NMR spectroscopic data, and the absolute configuration of 1 was established through single-crystal X-ray diffraction. All isolates were evaluated for their cytotoxicity against three cancer cell lines (B16 mouse melanoma, HepG2 human hepatocellular carcinoma, and MCF7 human breast adenocarcinoma), as well as their antimicrobial effects against Staphylococcus aureus, Escherichia coli, and Monilia albicans. As a result, compounds 1-4 displayed a certain degree of antimicrobial activities.

Synthesis and Antimicrobial Activity of Ursolic Acid Ester Derivatives.

Infections caused by microorganisms are a major cause of morbidity and mortality worldwide, and natural products continue to be important sources for the discovery of new antimicrobial agents. Ursolic acid is a triterpene with known antibacterial action, being naturally found in plants, such as Jaracanda oxyphylla and Jacaranda caroba (Bignoniaceae). Ursolic acid derivative esters have revealed potential biological activities, such as antitumor, antiviral, and antibacterial activity. In this study, sixteen esters (1-16) were synthesized from ursolic acid using DIC/DMAP and characterized by infrared (IR), nuclear magnetic resonance (1 H- and 13 C-NMR) and mass spectrometry. All ursolic acid esters were evaluated against Bacillus cereus, Staphylococcus aureus, Escherichia coli, Salmonella typhimurium, and the yeast Candida albicans. Six compounds are herein described for the first time (3, 9, 11, 13, 14 and 16) with yields up to 91.6 %. Compounds 11 (3ß-(3,4-dimethoxybenzoyl)ursolic acid) and 15 (3ß-nicotinoylursolic acid) displayed promising antifungal activity, with inhibition of C. albicans growth of 93.1 and 95.9 %, respectively.

Discovery of Meso-(meta-Pyridinium) BODIPY Photosensitizers: In Vitro and In Vivo Evaluations for Antimicrobial Photodynamic Therapy.

Antimicrobial photodynamic therapy (aPDT) has emerged as a novel and promising approach for the treatment of pathogenic microorganism infections. The efficacy of aPDT depends greatly on the behavior of the photosensitizer. Herein, we report the design, preparation, antimicrobial photodynamic activities, as well as structure-activity relationships of a series of photosensitizers modified at the meso position of a 1,3,5,7-tetramethyl BODIPY scaffold with various pyridinyl and pyridinium moieties. The photodynamic antimicrobial activities of all photosensitizers have been tested against Staphylococcus aureus, Escherichia coli, Candida albicans, and Methicillin-resistant S. aureus (MRSA). The methyl meso-(meta-pyridinium) BODIPY photosensitizer (3c) possessed the highest phototoxicity against these pathogens at minimal inhibitory concentrations (MIC) ranging from 0.63 to 1.25 µM with a light dose of 81 J/cm2. Furthermore, 3c exhibited an impressive antimicrobial efficacy in S. aureus-infected mice wounds. Taken together, these findings suggest that 3c is a promising candidate as the antimicrobial photosensitizer for combating pathogenic microorganism infections.

Bioactive triterpenoids from Solanum torvum fruits with antifungal, resistance modulatory and anti-biofilm formation activities against fluconazole-resistant candida albicans strains.

Vulvovaginal candidiasis (VVC) is the second most common vaginal infection that affects women of reproductive age. Its increased occurrence and associated treatment cost coupled to the rise in resistance of the causative pathogen to current antifungal therapies has necessitated the need for the discovery and development of novel effective antifungal agents for the treatment of the disease. We report in this study the anti-Candida albicans activity of Solanum torvum 70% ethanol fruit extract (STF), fractions and some isolated compounds against four (4) fluconazole-resistant strains of C. albicans. We further report on the effect of the isolated compounds on the antifungal activity of fluconazole and voriconazole in the resistant isolates as well as their inhibitory effect on C. albicans biofilm formation. STF was fractionated using n-hexane, chloroform (CHCl3) and ethyl acetate (EtOAc) to obtain four respective major fractions, which were then evaluated for anti-C. albicans activity using the microbroth dilution method. The whole extract and fractions recorded MICs that ranged from 0.25 to 16.00 mg/mL. From the most active fraction, STF- CHCl3 (MIC = 0.25-1.00 mg/mL), four (4) known compounds were isolated as Betulinic acid, 3-oxo-friedelan-20α-oic acid, Sitosterol-3-ß-D-glucopyranoside and Oleanolic acid. The compounds demonstrated considerably higher antifungal activity (0.016 to 0.512 mg/mL) than the extract and fractions and caused a concentration-dependent anti-biofilm formation activity. They also increased the sensitivity of the C. albicans isolates to fluconazole. This is the first report of 3-oxo-friedelan-20α-oic acid in the plant as well as the first report of betulinic acid, sitosterol-3-ß-D-glucopyranoside and oleanolic acid from the fruits of S. torvum. The present study has demonstrated the anti-C. albicans activity of the constituents of S. torvum ethanol fruit extract and also shown that the constituents possess anti-biofilm formation and resistance modulatory activities against fluconazole-resistant clinical C. albicans isolates.

Essential Oils and Supercritical CO2 Extracts of Arctic Angelica (Angelica archangelica L.), Marsh Labrador Tea (Rhododendron tomentosum) and Common Tansy (Tanacetum vulgare)-Chemical Compositions and Antimicrobial Activities.

Traditionally, arctic Finnish Angelica (Angelica archangelica L.), marsh Labrador tea (Rhododendron tomentosum, syn. Ledum palustre) and common tansy (Tanacetum vulgare) have been used as medicinal herbs in folklore medicine. However, these underutilised plants are a source of, e.g., oil-based compounds, which could benefit many modern applications implemented by the green chemistry extraction methods, as well. We extracted Angelica, marsh Labrador tea and common tansy by non-toxic and recyclable extraction methods, i.e., hydrodistillation and supercritical carbon dioxide (scCO2) extraction; characterised the essential oils (EOs) and scCO2 extracts by combination of gas chromatography and mass spectrometry (GC-MS), and in addition, analysed the antimicrobial properties. As expected for Angelica root and common tansy inflorescence, the scCO2 extraction method produced less amount of volatile compounds compared to hydrodistillation. On the other hand, more coumarins, alkanes, fatty alcohols and fatty acids were obtained. Additionally, sesquiterpenoids palustrol and ledol were predominant compounds in both marsh Labrador tea EO and scCO2 extract. According to our results, however, all the EOs and scCO2 extracts showed broad spectrum of antimicrobial activities against the selected microbes, but the effects were extract-specific. The strongest and broadest antimicrobial activities were performed by marsh Labrador tea scCO2 extract, which showed extremely strong effect on Staphylococcusaureus subsp. aureus and strong effect on Candida albicans.

Influence of Elicitation and Drying Methods on Anti-Metabolic Syndrome, and Antimicrobial Properties of Extracts and Hydrolysates Obtained from Elicited Lovage (Levisticum officinale Koch).

This research aims to investigate the influence of elicitation and drying methods (natural, convection, microwave, and freeze-drying), with jasmonic acid (JA) and yeast extract (YE) on the biological activity of extracts and hydrolysates from lovage (Levisticum officinale Koch) leaves. The results indicate that the highest TPC was determined for hydrolysates obtained from JA-elicited microwave-dried lovage (24.96 mg/gDW). The highest ACE and lipase inhibitory activity was noted for PBS extract obtained from JA-elicited lovage after microwave drying (EC50 = 0.16 and 0.12 mg/mL, respectively). Ethanolic extract from JA-elicited lovage after freeze-drying was characterized by the highest α-amylase inhibitory activity (EC50 = 3.92 mg/mL) and the highest α-glucosidase inhibitory activity (EC50 = 1.43 mg/mL) was noted for hydrolysates from control plants subjected to freeze-drying. The highest antimicrobial activity towards C. albicans yeasts was observed for microwave ethanolic extracts with minimal inhibition (MIC) and lethal (MLC) concentrations of 0.625 and 1.25 mg/mL, respectively.

Adenophora triphylla var. japonica Inhibits Candida Biofilm Formation, Increases Susceptibility to Antifungal Agents and Reduces Infection.

(1) Background: Candida is the most common cause of fungal infections worldwide, but due to the limited option of antifungal therapies, alternative strategies are required. (2) Methods: Adenophora triphylla var. japonica extract was used for the biofilm formation assay using RPMI1640. The combinatorial antifungal assay, the dimorphic transition assay, and the adherence assay were done to see the influence of inhibition of biofilm formation. qRT-PCR analysis were performed to check the gene expression. (3) Results: Adenophora triphylla var. japonica extract inhibited the Candida biofilm formation. Treatment of extract increased the antifungal susceptibility of miconazole from a 37% reduction in fungal growth to 99.05%, and also dose-dependently reduced the dimorphic transition of Candida and the attachment of Candida to HaCaT cells. The extract blocked the expression of hyphal-related genes, extracellular matrix genes, Ras1-cAMP-PKA pathway genes, Cph2-Tec1 pathway gene, and MAP kinase pathway gene. (4) Conclusions: In this study, the treatment of Adenophora triphylla var. japonica extract showed inhibition of fungal biofilm formation, activation of antifungal susceptibility, and reduction of infection. These results suggest that fungal biofilm formation is a good target for the development of antifungal adjuvants, and Adenophora triphylla var. japonica extract should be a good candidate for biofilm-associated fungal infections.

Chemical Composition and In Vitro Antioxidant and Antimicrobial Activities of Marrubium vulgare L.

In this study, the polyphenol content and the antioxidant and antimicrobial activities of hydroethanolic (MVE) and hydroacetonic (MVA) leaf extracts of Marrubium vulgare L. were examined. The results indicated that the total phenolic content was higher in MVA (112.09 ± 4.77 mg GAE/DW) compared to MVE extract (98.77 ± 1.68 mg GAE/DW). The total flavonoid content was also higher in MVA extract (21.08 ± 0.38 mg QE/g DW) compared to MVE (17.65 ± 0.73 mg QE/g DW). Analysis of the chemical composition revealed the presence of 13 compounds with a total of 96.14%, with the major compound being malic acid (22.57%). Both extracts possess a good total antioxidant activity. DPPH and FRAP assays indicated that the MVE extract possesses a better antioxidant activity, with IC50 = 52.04 µg/mL ± 0.2 and EC50 of 4.51 ± 0.5 mg/mL, compared to MVA extract (IC50 = 60.57 ± 0.6 µg/mL and EC50 of 6.43 ± 0.0411 mg/mL). Moreover, both extracts exhibited strong antimicrobial activity against certain nosocomial strains as indicted by the MIC values, which ranged between 0.93 mg/mL and 10 mg/mL. Taken together, these results reveal the importance of M. vulgare as a natural antioxidant with important antimicrobial activity.

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.

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.