Candida Albicans Strains Research Articles

Evaluation of the Antifungal Activity of Five Medicinal Plants on the In vitro Growth of a Multi-resistant Strain of Candida albicans

This paper focuses on determining the antifungal potential of plants traditionally used to treat infections. Five (5) plants were collected. The anti-Candida albicans activity was evaluated by the double dilution method in tilted tubes with the aqueous and hydroethanolic extracts of the different plants. The results showed that 70% ethanolic extracts were more active than the aqueous extracts for all the plants. The 70% ethanolic extract of Terminalia ivorensis (MFC = 1.56 mg/mL) was the most active on the tested strain. This was followed by Terminalia Superba (MFC = 3.125 mg/mL), Distemonanthus benthamianus (MFC = 50 mg/mL), Gmelina arborea (MFC= 50 mg/mL), and Justicia secunda (MFC ˃ 50 mg/mL). The phytochemical screening revealed the presence of seven (7) major groups of compounds. Saponosides are present only in the aqueous extracts of plants. Polyphenols, Flavonoids, Polyterpenes, and Sterols as well as Tanins are present in both alcoholic and aqueous extracts. These compounds could justify its activity and its traditional use. The interesting results obtained with the hydroethanolic extract of Terminalia ivorensis incite further research with this extract. A bio-guided study on the fractions from this extract could lead to the discovery of one or more molecules of interest in the fight against pathogenic fungi.

P076 Abdominal pain severity for IBD in remission correlates with genetic clustering and enzymatic activity of faeces-derived Candida albicans strains

Abstract Background Abdominal pain is a common occurrence for approximately 39% of patients with inflammatory bowel diseases in remission (quiescent IBD; qIBD). There is increasing evidence for a contributing role of the gastrointestinal fungal community (i.e., mycobiome) in relation to intestinal inflammation and irritable bowel syndrome (IBS). As such, abundance of Candida spp. and sub-species variation of Candida albicans were previously associated with IBD severity. In the current study, we aim to investigate mycobiome of patients with qIBD and qIBD with abdominal pain (qIBD–AP). Methods Patients with qIBD (defined as faecal calprotectin (FCP) ≤250 μg/g) with (n=91) or without (n=58) abdominal pain provided faecal samples. Abdominal pain was scored based on either the Irritable Bowel Syndrome Symptom Severity Scale (IBS–SSS) or Gastrointestinal Symptom Rating Score (GSRS) questionnaire. Faecal fungal communities were determined based on Internal Transcribed Spacer 1 (ITS1) sequencing. Cultivable yeasts from faecal samples were identified using Matrix Assisted Laser Deionization Time–of–Flight Mass Spectrometry. C. albicans strains (n=137 from 29 patients) were genotyped by ITS Sanger sequencing analysis and typing of seven microsatellite loci. Release of virulence-related enzymes (proteinase, phospholipase, lipase, esterase) by C. albicans was assessed through determination of precipitation zones on solid agar mediums containing enzyme-specific substrates. Results Descriptive mycobiota analysis revealed limited differences between compositions of qIBD and qIBD–AP patients, but a discriminative signature for abdominal pain was extracted using machine-based learning models. While ITS Sanger sequencing of faeces-derived C. albicans was insufficient to elucidate genetic variability, analysis of microsatellite loci revealed extensive variability and clustering into six clone clusters and a likely distinction between qIBD and qIBD-AP patients (Fig. 1). Phospholipase enzymatic activity of C. albicans strains correlated with GSRS–Abdominal Pain sub-score, as did proteinase activity with severity of abdominal pain according to the IBS–SSS (Fig. 2). Additionally, lipase activity inversely correlated with faecal calprotectin (Fig. 2). Conclusion The faecal gut mycobiome is associated with self–reported abdominal pain in patients with IBD in remission. This notion is based on both compositional and culture-dependent methods and specified clones of C. albicans may selectively contribute to abdominal pain for qIBD patients. This study opens further possibilities to investigate the role of faecal gut fungi in light of abdominal pain for qIBD-AP patients.

Synthesis, characterization, in-vitro biological evaluation and theoretical studies of 1,2,3-triazoles derived from triclosan as difenoconazole analogues

An efficient synthesis of novel difenoconazole analogues is described. The synthetic route involves a Friedel-Crafts acylation on triclosan molecule followed by a sequential azide formation/CuAAC reaction in a single synthetic operation leading to 1-(2‑chloro-5-(2,4-dichlorophenoxy)-4-hydroxyphenyl)-2-(4-(1-hydroxycyclohexyl)-1,2,3-triazol-1-yl)ethan-1-one derivatives in 50–96% yields. Synthesized 1,2,3-triazoles were evaluated for activity against diverse strains including bacterial strains of Staphylococcus aureus ATCC 29213, Escherichia coli ATCC 700891 and fungal strain Candida albicans ATCC 90028. A 1,2,3-triazole derivative bearing a CH(OH)CH3 group displayed a selective activity against Methicillin-resistant Staphylococcus aureus (MRSA) comparable to Gentamicin standard. This selectivity can be attributed to a conformation adopted by 5‑chloro-2-(2,4-dichloro-phenoxy)-phenol core enabling non-covalent interactions presenting a higher activity based on Fukui function on triazole ring.

Activity of Colloidal Silver Solution against Microorganisms Implicated in Ocular Infections

Endophthalmitis most likely originates from both planktonic bacteria suspended in the tear film and bacteria adherent to the conjunctiva and the eyelid. This study aimed to expand the research on the effectiveness of a colloidal silver solution (Silverix®) against ocular microorganisms. The activity of Silverix® was evaluated against methicillin-resistant Staphylococcus aureus, S. epidermidis, ofloxacin-resistant Pseudomonas aeruginosa, and Candida albicans strains, previously characterized for their antibiotic resistance and biofilm-forming capabilities. The microbial killing was estimated at various times in the presence and absence of colloidal silver solution against planktonic and biofilm-embedded cells. The results documented the efficacy of Silverix® on planktonic cells of S. aureus and S. epidermidis (2.49–2.87 Log CFU/mL reduction) and P. aeruginosa strains (3–4.35 Log CFU/mL reduction). On the contrary, C. albicans showed mild susceptibility. Regarding early biofilm, the ocular isolates were harder to kill (2–2.6 Log CFU/mL reduction) than the reference strains, whereas a similar decrease (3.1 Log CFU/mL reduction) was estimated for P. aeruginosa strains. The light microscope images of biofilms treated with colloidal solution confirmed the ability of Silverix® to destroy the biofilm.

Clinical effect of standardized nursing for lymphoma patients and the influencing factors of nosocomial infection.

To analyze the clinical effect of standardized nursing for lymphoma patients and the influencing factors of nosocomial infection, a total of 360 diffuse large B-cell lymphoma patients with disease recurrence or progression after first-line treatment were retrospectively selected from our hospital from January 2021 to July 2022. After standardized nursing, the overall infection rate of lymphoma patients was 2.50% (9/360), which was significantly lower than the overall infection rate of our hospital in 2021 (7.44%, 844/11342) (P < .05). The proportion of 3 kinds of pathogenic bacteria detected were G+ bacteria (33.5%), G- bacteria (53.3%), and fungi (13.2%). The pathogenic bacteria genus with the most G+ bacteria is Enterococcus, the pathogenic bacteria genus with the most G+ bacteria is Enterobacteriaceae, and the pathogenic bacteria with the most fungi is Candida albicans. Female infection rate was significantly higher than male (P < .05). There was no significant difference in nosocomial infection among different marital status/fertility status (P > .05). The nosocomial infection of patients with different hospitalization times was statistically significant (P < .05). The duration of hospitalization in the infected group was significantly higher than that in the non-infected group (P < .05). The clinical effect of standardized nursing for lymphoma patients is significant, and the influencing factors of nosocomial infection include patient gender, hospitalization frequency, and hospitalization duration.

Examining the effects of BRG1 over-expression on Candida albicans strains growing as pseudohyphae.

The pathogen Candida albicans is pleiomorphic and grows in yeast and filamentous forms but the relationship between the regulation of different filamentous forms is unclear. BRG1 encodes a DNA binding protein which is an important regulator of morphology. Mutants lacking BRG1 grow as yeast under all conditions tested and over-expressing BRG1 drives hyphal growth even in the absence of inducing signals. A number of genetic mutants in repressors of filamentation form pseudohyphae under yeast conditions and some of these mutants can form hyphae under hypha-inducing conditions. This study examines the position of BRG1 in the regulatory networks that govern filamentation by examining the effect of over-expressing BRG1 in pseudohyphal mutants.

LC-MS Analysis and Antifungal Activity of Turnera subulata Sm.

Fungi of the Candida genus are responsible for invasive candidiasis, which affects people all over the world and has high mortality rates. This is due to their virulence factors, which give them great resistance and pathogenicity. In addition, the emergence of multidrug-resistant strains makes it difficult to treat these infections. In this way, natural products have emerged as an alternative to standard drugs, where plants known for their medicinal properties such as Turnera subulata become attractive to research. The present work aimed to analyze the ethanol extract of Turnera subulata leaves against standard strains of Candida albicans, Candida krusei and Candida tropicalis using broth microdilution techniques. The identification of the compounds in T. subulata leaves by LC-MS revealed the presence of a wide variety of substances such as carboxylic acids and terpenes, with flavonoids and fatty acids being more evident. The antifungal assays showed that the extract was not able to inhibit the growth of the tested strains at concentrations with a clinical relevance. However, at higher concentrations, it was able to inhibit the fungal dimorphism of C. albicans and C. tropicalis. It is possible that the T. subulata extract has potential as an inhibitor of fungal virulence factors without affecting the cell viability. Further research should be carried out in order to assess its inhibitory potential for other fungal virulence factors.

Antimicrobial and mechanical properties of functionalized textile by nanoarchitectured photoinduced Ag@polymer coating.

The control of microbial proliferation is a constant battle, especially in the medical field where surfaces, equipment, and textiles need to be cleaned on a daily basis. Silver nanoparticles (AgNPs) possess well-documented antimicrobial properties and by combining them with a physical matrix, they can be applied to various surfaces to limit microbial contamination. With this in mind, a rapid and easy way to implement a photoinduced approach was investigated for textile functionalization with a silver@polymer self-assembled nanocomposite. By exposing the photosensitive formulation containing a silver precursor, a photoinitiator, and acrylic monomers to a UV source, highly reflective metallic coatings were obtained directly on the textile support. After assessing their optical and mechanical properties, the antimicrobial properties of the functionalized textiles were tested against Escherichia coli (E. coli) and Candida albicans (C. albicans) strains. In addition to being flexible and adherent to the textile substrates, the nanocomposites exhibited remarkable microbial growth inhibitory effects.

Еffect of the essential oil of &lt;i&gt;Satureja montana&lt;/i&gt; L. on the growth of cultures of conditionally pathogenic microorganisms

Introduction. Essential oils contain antimicrobial components that are highly active against a wide range of microorganisms. Essential oils are natural, environmentally safe, low-toxic substances with a minimal list of side effects; no antimicrobial resistance is formed to them.&#x0D; The aim of the research was to study the influence of the essential oil of Satureja montana L., growing in the Crimea, on the growth of cultures of opportunistic microorganisms.&#x0D; Materials and methods. The short-term effect of savory oil on the growth of referenсе strains of microorganisms was studied in accordance with the European Standard for determining the rate of inactivation of microorganisms by the test substance (1997). To study the long-term effect of savory oil on clinical isolates of Staphylococcus aureus, we used the method of dilutions in a liquid medium, followed by measurement of the optical density of growth of the suspension culture biomass. The effect of savory oil on the formation of biofilms by clinical isolates of S. aureus was also studied.&#x0D; Results. Whole savory oil and its dilutions of 1 : 10 and 1 : 100 with short-term action (1060 min) completely suppressed the growth of referenсе strains of bacteria; growth of the referenсе strain Candida albicans CCM 885 was inhibited only by whole oil and a 1 : 10 dilution, while a 1 : 100 dilution had a bacteriostatic effect. Dilutions of essential oil 1 : 100 and 1 : 1000 had a pronounced antibacterial effect on the suspension culture of clinical isolates of S. aureus. Savory oil also inhibited biofilm formation by 11 isolates S. aureus.&#x0D; Conclusion. The essential oil of Satureja montana L. exhibits a pronounced antimicrobial effect against referenсе strains of S. aureus ATCC 25923, Escherichia coli ATCC 25922 and fungi C. albicans CCM 885. The antibacterial effect of this essential oil on clinical isolates of S. aureus allows us to offer it as a component of combined preparations for the treatment of infections caused by antibiotic-resistant strains of staphylococcus.

Investigation of antioxidant and antimicrobial activities of walnut (Juglans regia L.) kernel septum

Objectives: Walnut (Juglans regia L.) kernel septum (or septa) (WKS), a traditional nutraceutical material in China, has not been explored in detail. In this study, antimicrobial activity, total phenolic content (TPC) and antioxidant-oxidant status of WKS was investigated in case it may be clinically important in the management of various complications. Methods: The WKS was extracted with ethanol in a Soxhlet device. TPC of WKS was analysed by using Folin-Ciocalteu’s method. Antioxidant activity was obtained by using Rel Assay Diagnostics kits. The antimicrobial activity of WKS was evaluated against two Gram-positive (Staphylococcus aureus, Bacillus subtilis), one Gram-negative bacteria (Escherichia coli) and one fungus (Candida albicans) strains using the agar diffusion method. Results: The TPC of WKS was found to be 119.42 ± 2.39 mg GAE/gDW. It was determined that total antioxidant status (TAS), total oxidant status (TOS) and oxidative stress index (OSI) values were 7.542 ± 0.389 mmol/L, 3.718 ± 0.287 µmol/L and 0.049 ± 0.001, respectively. WKS selectively inhibited the growth of Gram-positive bacteria and fungus, while S. aureus was the most susceptible one with 16 mm of inhibition zone. Gram-negative bacteria was resistant to the extract. Conclusions: As far as we know, this paper is the first work that demonstrates the antioxidant-oxidant status of WKS by using the method described above, and moreover there are no scientific reports which have examined WKS in such a multidisciplinary experimental design. This study strongly supports the reported traditional use of WKS. Results indicated that WKS can be used as a pharmacological natural agent due to its high antioxidant and antimicrobial activities.

Synthesis of novel tetrazolic derivatives and evaluation of their antimicrobial activity

The microbial resistance to various anti-infective drugs remains a major worldwide health problem. Therefore, the search for novel and effective antimicrobial agents is of paramount importance to combat these pathogenic microorganisms. The present study includes the synthesis of novel Bis(arylidene-2-[(tetrazol-5-yl)]alkane derivatives and the evaluation of their antibacterial and antifungal activities against four bacterial strains (Listeria innocua, Escherichia Coli, Pseudomonas aeruginosa, Staphylococcus aureus) and four fungal strains (Candida albicans, Rhodotorula glutinis, Geotrichum candidum, Aspergillus niger). These tetrazoles derivatives were prepared with moderate yields and their structures were determined on the basis of spectroscopic analyses, including FT IR, NMR, and HR-ESI-MS. Subsequently, these compounds and their precursors were tested in vitro for their antibacterial and antifungal activities, using the agar-disc diffusion method. All synthesized compounds at concentration of 1 mg/ml exhibited some antimicrobial properties against the tested fungal and bacterial strains. Finally, the docking study on the Biotin protein ligase in Staphylococcus aureus, showed that all molecules interact with the active site.

Untargeted metabolomics to evaluate antifungal mechanism: a study of Cophinforma mamane and Candida albicans interaction

Microbial interactions between filamentous fungi and yeast are still not fully understood. To evaluate a potential antifungal activity of a filamentous fungus while highlighting metabolomic changes, co-cultures between an endophytic strain of Cophinforma mamane (CM) and Candida albicans (CA) were performed. The liquid cultures were incubated under static conditions and metabolite alterations during the course were investigated by ultra-performance liquid chromatography–tandem mass spectrophotometry (UPLC–MS/MS). Results were analyzed using MS-DIAL, MS-FINDER, METLIN, Xcalibur, SciFinder, and MetaboAnalyst metabolomics platforms. The metabolites associated with catabolic processes, including the metabolism of branched-chain amino acids, carnitine, and phospholipids were upregulated both in the mono and co-cultures, indicating fungal adaptability to environmental stress. Several metabolites, including C20 sphinganine 1-phosphate, myo-inositol, farnesol, gamma-undecalactone, folinic acid, palmitoleic acid, and MG (12:/0:0/0:0) were not produced by CA during co-culture with CM, demonstrating the antifungal mechanism of CM. Our results highlight the crucial roles of metabolomics studies to provide essential information regarding the antifungal mechanism of C. mamane against C. albicans, especially when the lost/undetected metabolites are involved in fungal survival and pathogenicity.Graphical

Immune Defences: A View from the Side of the Essential Oils.

The use of essential oils is increasingly being investigated among new therapeutic approaches based on medicinal plants and their extracts. With the wide use of synthetic and semi-synthetic antimicrobial drugs, the spread of drug-resistant clinical isolates has increased, and research is directed towards natural products, such as essential oils, as useful antimicrobial resources. In the context of a prospective infection, we compared the impact of essential oils and common antimicrobial agents on the microbicidal activity of human phagocytes. Here, we present the results of our decades-long investigation into the effectiveness of thyme red oil (26.52% thymol chemotype), tea tree oil (TTO), and Mentha of Pancalieri [(Mentha x piperita (Huds) var. officinalis (Sole), form rubescens (Camus) (Lamiaceae)] essential oils on human polymorphonuclear leukocytes (PMNs) capacity to kill clinical strains of Candida albicans and C. krusei when compared to three antifungal drugs used to treat candidiasis (fluconazole, anidulafungin, and caspofungin) These essential oils demonstrate antifungal drug-like and/or superior efficacy in enhancing intracellular killing by PMNs, even at subinhibitory concentrations. Our results are compared with data in the literature on essential oils and immune system interactions. This comparison would aid in identifying therapeutic solutions to the increasingly prevalent antibiotic resistance as well as filling in any remaining knowledge gaps on the bioactivity of essential oils.

Hydrogen peroxide enhances the efficacy of photodynamic therapy against Candida albicans biofilms

The present study aimed to evaluate the effectiveness of hydrogen peroxide (H2O2) combined with antimicrobial photodynamic therapy (aPDT) on biofilms formed by Candida albicans strains which are either susceptible to or resistant to fluconazole. Biofilms were grown and treated with H2O2, followed by the application of Photodithazine® (P) and red light-emitting diode (LED) (L) either separately or combined (n = 12). After the treatment, biofilms were evaluated by estimating colony-forming unit ml−1, extracellular matrix components [water -soluble and -insoluble polysaccharides, proteins, extracellular DNA (eDNA)], biomass (total and insoluble dry-weight), and protein concentration. Biofilms formed by both strains presented a significant reduction in cell viability, biomass, extracellular matrix components (both types of polysaccharides, eDNA), and proteins (in the soluble and insoluble portion of biofilms) compared to the control. Microscopy images of the biofilms after treatments showed disarticulation of the matrix and scattered fungal cells. The application of H2O2 can disturb the organization of the extracellular matrix, and its association with aPDT potentiated the effect of the treatment.

In vitro antimicrobial activity of colloidal nano silver

The antimicrobial effect of colloidal nanosilver (AgNPs) at concentrations of 20 and 30 ppm against reference Esherichia coli, Salmonella enterica, Staphylococcus aureus, Clostridium perfringens, Candida albicans strains and two clinical isolates (Pseudominas aeruginosa and Streptococcus pyogenes) was tested. The classical agar diffusion method, determination of the minimum inhibitory concentrations (MIC) and the time of antimicrobial action of AgNPs were used. In the studies performed by the agar diffusion method, a very good inhibitory effect of AgNPs 30 ppm and to a much lesser extent of AgNPs 20 ppm, was reported against all studied microorganisms. The studied Gram-negative bacteria showed higher sensitivity to both preparations compared to the Gram-positive microorganisms (P&gt;0.05). The lowest sensitivity was reported for S. aureus and C. albicans, and the highest - for P. aeruginosa and S. pyogenes. The lowest MICs of AgNPs 20 ppm were reported for P. aeruginosa and C. perfringens. For them, the MIC50 was 1 μg/mL, and for the rest - 2 μg/mL. Again, C. perfringens showed the highest sensitivity to AgNPs 30 ppm with MIC50 0.5 μg/mL, and the lowest one was that of S. aureus with MIC50 2 μg/mL. For the Gram-positive bacteria MIC values were higher than for Gram-negative ones. AgNPs 20 ppm and AgNPs 30 ppm inactivated all bacterial strains tested at final concentrations of 103 cells/mL and 104 cells/mL within 5 min; only C. albicans persisted longer. The tested microorganisms remained viable for significantly longer time in the presence of AgNPs 20 ppm and AgNPs 30 ppm when in suspensions with a density of 106 cells/mL. These results are promising for the successful use of AgNPs for disinfection, as well as for topical therapy of infections involving these bacterial species.

Análise antifúngica da incorporação do óleo essencial de Cymbopogon citratus (d.c.) Stapf em polimetacrilato de metila

ABSTRACT Objective: Evaluated the antifungal effect of the incorporation of different concentrations of the essential oil Cymbopogon citratus (capim santo), into polymethylmethacrylate (PMMA) against Candida albicans. Methods: Fifty specimens were fabricated and divided into five groups: Group 1, PMMA + 10% essential oil (n=10); Group 2, PMMA + 15% essential oil (n=10); Group 3, PMMA + 20% essential oil (n=10); Group 4, PMMA + 25% essential oil (n=10); Group 5, PMMA (n=10). PMMA powder was mixed with the monomer and the mixture was placed in disc-shaped cavities measuring 15 mm in diameter, 2 mm thick. To evaluate the antifungal activity of the experimental specimens, the standard strain of Candida albicans was tested. After incubation, the colony count of each plate was performed using a digital colony counter, obtaining the number of colony forming units (CFU) and the Kruskal-Wallis test was applied. Results: There was statistically significant difference in the CFU count of Candida albicans as a consequence of the addition of Cymbopogon citratus essential oil to PMMA (p &lt; 0.001) and values were significantly higher in comparison with those of all the other groups, when the essential oil was incorporated as incorporated into the PMMA in the concentration of 20%. In the other concentrations, no difference in values was observed in comparison with the Control Group without essential oil of Cymbopogon citratus. Conclusion: The acrylic resin with the essential oil incorporated into it in different concentrations provided no effect against development of the genus Candida.

Evaluating the typing power of six isoenzymatic systems for differentiation of clinical and standard isolates of Candida species

Background: Due to the increasing prevalence of candidiasis, early detection of the causative agents may pave the way for the management of this infection. The present study aimed to assess the discriminative power of the six isoenzymatic systems for differentiating the Candida species.Materials and Methods: Sixteen standard Candida albicans and Candida dubliniensis strains and 30 fluconazole-sensitive and fluconazole-resistant clinical strains of Candida albicans were analyzed using a Multilocus Enzyme Electrophoresis (MLEE) method, including six enzymatic systems consisting of malate dehydrogenase (MDH), phosphoglucomutase (PGM), glucose-phosphate isomerase (GPI), glucose-6-phosphate dehydrogenase (G6PDH), 6-phosphogluconate dehydrogenase (6PGD), and malic enzyme (ME).Results: Among the six enzymatic systems, ME showed no diagnostic activity, whereas MDH provided the best species-specific pattern for species discrimination. In addition, the MDH and G6PD systems provided a discriminatory pattern for differentiating C. dubliniensis from C. albicans isolates. The same isoenzymatic activity was detected in all 36 standard and clinical isolates. Moreover, the results showed no correlation between the isoenzymatic profiles and drug resistance.Conclusion: Among the investigated MLEE systems, MDH was able to differentiate between Candida albicans and Candida dubliniensis. Although no association was detected between isoenzyme patterns and fluconazole resistance in this investigation, isoenzyme patterns are likely correlated with virulence factors between species and even within species. To answer these questions, additional studies should be done on more strains.

Screening of 3-acetylcoumarin derivatives as multifunctional biological agents

In this work, the multifunctional potential of four 3-acetylcoumarin derivatives was studied. The derivatives were significantly active against bacteria Staphylococcus aureus, Pseudomonas aeoginosa and fungal strain Candida albicans. The results of antioxidant activity assays were promising when compared to ascorbic acid. The in vitro anticancer activity was carried out using MTT assay on human cancer cell line COLO-205 and 3ACDT showed commendable antiproliferative activity along with appreciable tumor selectivity with distinct selectivity index. Moreover, ADMET properties of the compounds were determined using the pKCSM and SwissADME online tools and all compounds were found with good pharmacokinetic profile. Hence, from the obtained results from all the 3-acetylcoumarin derivatives, 3ACDT exhibited good therapeutical potential and can be optimized for lead development.

Evaluation of In vivo Toxicity and In vitro Antimicrobial Activities of Crude Ethanolic Stem Bark Extract of Anonidium mannii

Aims: This study aims to evaluate the in vivo acute and sub-acute toxicity; and the antimicrobial activity of Anonidium mannii stem bark ethanolic extract.&#x0D; Study Design: This is an experimental study.&#x0D; Location and Duration of the Study: The work was conducted from 15 November 2020 to 31 May 2021 at several laboratories (the Faculty of Medicine and Pharmaceutical Sciences Laboratory of the University of Douala, the Animal Physiology Laboratory of the Faculty of Medicine and Biomedical Sciences at the University of Yaoundé 1 and in the Hematology and Bacteriology Laboratories of the District Hospital of the Cité des Palmiers, Douala, Cameroon).&#x0D; Methodology: The in vivo acute and subacute toxicities studies were conducted following the guidelines of the OECD on Wistar rats, while the in vitro antimicrobial activity was evaluated using the microdilution method on bacterial (Neisseria gonorrheae, Escherichia coli, Salmonela spp) and fungal (Candida albicans) strains.&#x0D; Results: Phytochemical screening revealed the presence of alkaloids, anthraquinones, coumarins, flavonoids, phenols, reducing sugars, tannins, triterpenes. An oral administration of the extract did not induce an abnormal variation of the physiological parameters in rats, at doses of 2000 and 5000 mg/kg body weight for 14 days. After twenty-eight days of observation during the study of subacute toxicity, the extract showed good safety in terms of subacute toxicity. No deaths were recorded at the different doses; and clinical and physiological parameters analyses revealed a non-significant statistical difference. All bacterial strains in the presence of the extract were inhibited, as well as C. albicans. The extract exhibited strong antibacterial activity against N. gonorheae (MIC 15.6 μg/mL), E. coli (MIC 62.5 μg/mL) and Salmonella spp (MIC 15.6 μg/mL).&#x0D; Conclusion: These results could justify the use of A. mannii stem bark in the traditional pharmacopoeia for the treatment of gonococcal disease, diarrhea, abscesses and food poisoning.

Ammonium chloride and urea based deep eutectic solvent: toxicological and antioxidant profile Authors

In the present study, the toxicity potential of ammonium chloride and urea-based deep eutectic solvent (DES) was studied. A homogeneous DES solution was obtained by heating at 60°C for 20 minutes. Fourier Transform Infrared Spectroscopy (FTIR) analysis was used to verify the synthesis. The toxicity profiling of ammonium-based DES was performed using in vitro cell lines (fibroblast growth factor) and microbes (fungi, Gram positive and gram negative bacteria) and in vivo model organism (fish). DES was found to the had maximum zone of inhibition against tested bacterial (Staphylococcus aureus) and fungal strains (Candida albicans). Ammonium chloride-urea DES had higher LC50 against Cyprinus carpio. DES was found to have a higher percentage of cell viability at higher concentration along with DPPH scavenging activity of 92%. In conclusion, ammonium chloride-urea based DES had been successfully formed and found less harmful at higher concentrations, thus can be used as promising solvents in the future.