Article

Aloe vera extract reduces both growth and germ tube formation by Candida albicans

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  • CITE - Center for Innovation Technology and Education
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Abstract

Due to the increased number of immunocompromised patients, the infections associated with the pathogen of the genus Candida have significantly increased in recent years. To grow, Candida albicans may form a germ tube extension from the cells, which is essential for virulence. In this work, we studied the effect of crude glycolic extract of Aloe vera fresh leaves (20% w/v) on growth and germ tube formation by C. albicans. The C. albicans growth was determined in the presence of different concentrations of A. vera extracts in Sabouraud dextrose broth medium. In the presence of A. vera extract (10% v/v), the pronounced inhibition in the C. albicans growth (90-100%) was observed. This inhibition occurred parallel to the decrease in the germ tube formation induced by goat serum. Our results demonstrated that A. vera fresh leaves plant extract can inhibit both the growth and the germ tube formation by C. albicans. Our results suggest the possibility that A. vera extract may be used as a promising novel antifungal treatment.

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... The process yielded 2mL of essential oil, which was stored in refrigerated and dark conditions. The effects of the R. offi cinalis essential oil on germ tube formation were assessed as described by Bernardes et al. 8 with some modifi cations. Briefl y, germ tube formation was rapidly induced in Sabouraud dextrose broth using 10% fetal bovine serum and either 4% R. offi cinalis essential oil and 0.02% Tween 80 (assay tube) or nothing (control tube), with 10ml as a fi nal volume. ...
... Consistent with our results, Bernardes et al. 8 observed a 95% reduction in germ cell formation when C. albicans cells (ATCC 10-231) were treated with raw glycolic 10% (v/v) extract from fresh Aloe vera leaves. Interestingly, Pinto et al. 10 demonstrated an effect of the Ferulago capillaris essential oil on cells during inhibition of germ tube formation in C. albicans, which demonstrated that oxidative stress affects the enzymatic activity as well as cell mitochondrial membrane potential and results in growth inhibition and death. ...
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Introduction: The aim of this study was to investigate the effects of Rosmarinus officinalis essential oil on germ tube formation by Candida albicans isolated from denture wearers. Methods: Ten C. albicans isolates recovered from denture wearers were tested using 10% fetal bovine serum with or without 4% R. officinalis essential oil. Results: The essential oil from R. officinalis completely inhibited germ tube formation in the investigated C. albicans isolates. Conclusions: The results demonstrate that the essential oil of R. officinalis modulates C. albicans pathogenicity through its primary virulence factor (i.e., germ tube formation was suppressed).
... It markedly declined the growth of candida albicans in parallel, inhibiting the germ tube formation. They concluded aloe vera leaf extract can be a novel antifungal drug (Bernardes et al., 2012). The growth and germ tube formation of candida were also observed using diphenyl Di selenides and diphenyl ditelluride. ...
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Sweetpotato (Ipomoea batatas L) is a global food crop now recognized as a functional food due to several nutraceutical components. There is a need for continuous evaluation and selection of cultivars with the appropriate phytochemical composition and bioactivities to fully explore the crop’s medicinal value. Studies aimed at the isolation, characterization, and toxicological evaluation of its bioactive compounds may help to strengthen and confirm the possible role of sweetpotato as a health-promoting food and an alternative remedy for chronic diseases. This study aimed to evaluate the antimicrobial susceptibility testing of various varieties of crude leaf extracts in vitro. Antimicrobial action (in vitro) of 70% acetone of different sweetpotato leaf extract variants was analyzed against positive fungi candida albicans ATCC90028. The experiment used Sabourared and Mueller Hinton culture plates using EUCAST disc diffusion methods at different concentrations. The results revealed that 70% acetone extraction of sweetpotato leaves shows low antimicrobial activity against candida albicans. On the other hand, crude leaf extracts from green lemon, butter squash, bell pepper, and garlic have medium to high antibacterial activity. Based on this study, consuming leafy vegetables could help protect consumers from antimicrobial infections against candida.
... It markedly declined the growth of candida albicans in parallel, inhibiting the germ tube formation. They concluded aloe vera leaf extract can be a novel antifungal drug (Bernardes et al., 2012). The growth and germ tube formation of candida were also observed using diphenyl Di selenides and diphenyl ditelluride. ...
Article
Full-text available
Sweetpotato (Ipomoea batatas L) is a global food crop now recognized as a functional food due to several nutraceutical components. There is a need for continuous evaluation and selection of cultivars with the appropriate phytochemical composition and bioactivities to fully explore the crop’s medicinal value. Studies aimed at the isolation, characterization, and toxicological evaluation of its bioactive compounds may help to strengthen and confirm the possible role of sweetpotato as a health-promoting food and an alternative remedy for chronic diseases. This study aimed to evaluate the antimicrobial susceptibility testing of various varieties of crude leaf extracts in vitro. Antimicrobial action (in vitro) of 70% acetone of different sweetpotato leaf extract variants was analyzed against positive fungi candida albicans ATCC90028. The experiment used Sabourared and Mueller Hinton culture plates using EUCAST disc diffusion methods at different concentrations. The results revealed that 70% acetone extraction of sweetpotato leaves shows low antimicrobial activity against candida albicans. On the other hand, crude leaf extracts from green lemon, butter squash, bell pepper, and garlic have medium to high antibacterial activity. Based on this study, consuming leafy vegetables could help protect consumers from antimicrobial infections against candida.
... C. albicans is pleomorphic in nature, and its germ tube formation is a phenotypic feature that is required for its pathogenicity [50]. C. albicans, in its germ tube form, adheres to host cells more efficiently and competently. ...
Article
Candida spp. is one of the most common opportunistic human fungal pathogens, responsible for 90–100% of mucosal infections. Germ tube formation, hyphal morphogenesis, the production of tissue-damaging extracellular enzymes, and drug-resistant biofilm formation contribute to their pathogenicity, which can lead to systemic infections in the worst scenarios. Thus, there is an urgent need to discover new therapeutic agents to overcome the above virulence factors. Therefore, we aimed to prepare Crinum latifolium leaves-mediated biosynthesis of gold nanoparticles (AuNPs) that was characterized by various sophisticated techniques, and further their antifungal, antibiofilm, and anti-virulence activities was investigated. The AuNPs show a zone of inhibition between 19 and 22 mm for test strains of Candida spp. at 1000 µg/ml, whereas the MIC values were ranged from 250 to 500 µg/ml. AuNPs inhibit germ tube formation in C. albicans by 93.3% at 50 µg/ml. Furthermore, exposure to AuNPs significantly reduced the secretions of phospholipase, proteinase, hemolysin, esterase, and lipase. Confocal laser scanning microscopy (CLSM) investigation shows that 25 µg/ml of AuNPs significantly inhibit colonization and biofilm formation. Lastly, the interaction of Candidal cells with AuNPs revealed, ultrastructural changes in the cell wall and cell membranes as visualized by a transmission electron microscope (TEM).
... Both blastoconidia and hyphae play a crucial role in pathogenesis; however, these display different functions, which include adhesion and invasion [82]. Several studies have focused on inhibiting these morphological transitions in pathogenic fungi; nevertheless, there is scarce knowledge about the action of natural compounds against this virulence trait in C. albicans [83][84][85][86][87][88][89]. Some natural and synthetic compounds have been tested and found to be effective in affecting germ tubes or pseudo-hyphae in C. albicans [77,80,84,85]. ...
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Due to the increased incidence of fungal infections and the emergence of antifungal resistance mainly by Candida species, the need for safe and effective novel therapies is imperative. Consequently, plants and herbs are a powerful source to combat infections. Here, we evaluated the anti-Candida potential of an ethanolic extract from Piper nigrum. The phytochemical analysis of P. nigrum revealed bioactive compounds such as alkaloids, terpenoids, and tannis. Our results showed that P. nigrum extract suppressed the virulence factors of C. albicans strains, including hyphae formation in both liquid and solid media, reduced secretion of phospholipases/proteinases, and affected biofilm formation. Furthermore, the P. nigrum extract showed no hemolytic effect in vitro and exhibited reduced cytotoxicity on Vero cells and G. mellonella larvae at concentrations that inhibited hyphae and biofilm in C. albicans. Moreover, the extract demonstrated antifungal activity against C. auris strains. In conclusion, the P. nigrum extract affected the growth and morphogenesis of Candida (even in resistant strains), demonstrating that this plant has an anti-candida activity and represents a promising resource for discovering novel antifungal compounds.
... The effect of OCLE on C. albicans ATCC 10231 tube formation was studied through the method of Bernardes et al., with slight modifications [110]. C. albicans germ-tube formation was induced in Sabouraud Dextrose Broth (SDB) (Oxoid, Milan, Italy) with 10% (v/v) of fetal bovine serum (FBS) (Sigma-Aldrich, Milan, Italy). ...
Article
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Candida albicans (C. albicans) and Candida glabrata (C. glabrata) are part of the human microbiome. However, they possess numerous virulence factors, which confer them the ability to cause both local and systemic infections. Candidiasis can involve multiple organs, including the eye. In the present study, we investigated the anti-candidal activity and the re-epithelizing effect of Orobanche crenata leaf extract (OCLE). By the microdilution method, we demonstrated an inhibitory effect of OCLE on both C. albicans and C. glabrata growth. By crystal violet and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, we showed the ability of OCLE to inhibit the biofilm formation and the viability of yeast cells, respectively. By germ tube and adhesion assays, we proved the capacity of OCLE to affect the morphological transition of C. albicans and the adhesion of both pathogens to human retinal pigment epithelial cells (ARPE-19), respectively. Besides, by MTT and wound healing assay, we evaluated the cytotoxic and re-epithelizing effects of OCLE on ARPE-19. Finally, the Folin-Ciocalteu and the ultra-performance liquid chromatography-tandem mass spectrometry revealed a high content of phenols and the presence of several bioactive molecules in the extract. Our results highlighted new properties of O. crenata, useful in the control of Candida infections.
... The A. vera has also been reported to contain metabolites with antifungal properties / minimal fungicidal effect against the mycelial growth of different fungal species [1, [74][75][76], especially inhibiting the growth of Candida albicans [77,78]. The antifungal property of A. vera is due to the presence of compounds such as lupeol, salicylic acid, urea, nitrogen, cinnamomic acid, phenols and sulphur [65]. ...
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Background Aloe barbadensis (Miller) is one of the most used medicinal herbs in the world since antiquity due to its valuable application as pharmacological properties. The species of A. vera are widely distributed and cultivated throughout the world. Objective This review article aims to present an account of information on phytochemistry, pharmacological properties of bioactive compounds from A. vera highlighting the mechanism of action and functional food supplement to improve human health. The development of A. vera based phytomedicines and its future trends were also evaluated. Methods A bibliographic search of scientific literature published till March 2020 was carried out from the scientific databases and different search engines such as PubMed, ScienceDirect, Cochrane library, and Scopus. The keywords used in several combinations included: Aloe vera, phytochemistry, pharmacological activity, treatment, prevention, disease, health, in vitro, in vivo and clinical studies. From eligible articles, the data were independently extracted by standard data extraction method. Results A. vera is a good source of bioactive compounds. A. vera has been reported for numerous therapeutic applications. Besides several valuable therapeutic potentials, the plant has been also used as crop and food preservation as well as a functional food supplement due to the presence of high content of carbohydrates, vitamins and several antioxidant molecules. Its oral ingestion has been related to diarrhea, electrolyte imbalance, kidney dysfunction, drug interactions, dermatitis, erythema, and phototoxicity. Conclusion Although there are several A. vera-based products available, the knowledge on the relationship between biological and therapeutic properties should be clearly defined to ascertain the exact action mechanism(s) to develop new drugs.
... Kandungan senyawa polifenol tersebut juga dimiliki oleh ekstrak lidah buaya dan kunyit yang sering digunakan sebagai obat alami. 11,12 Flavonoid menghambat C. albicans dengan cara menghambat sintesis glukan. 14 Penghambatan pertumbuhan C. albicans juga dapat dilakukan dengan menghambat perlekatan dengan sel host. ...
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Itraconazole merupakan salah satu obat sintetik yang memiliki keterbatasan dalam menghambat pertumbuhan Candida albicans (C. albicans). Kulit buah durian (Durio zibethinus L.) merupakan salah satu tanaman yang memiliki efek antifungal karena mengandung senyawa organik seperti flavonoid, tanin, dan saponin yang mampu menghambat pertumbuhan C. albicans. Tujuan dari penelitian ini adalah untuk menetapkan potensi pengaruh pemberian kombinasi ekstrak kulit buah durian dengan dan tanpa itraconazole terhadap pertumbuhan C. albicans in vitro. Penelitian ini menggunakan metode checkerboard dengan 6 jenis konsentrasi ekstrak kulit buah durian dan 5 jenis konsentrasi iatraconazole dalam menentukan KHM kombinasi. KHM kombinasi bahan uji diuji pada media SDA untuk menetapkan pengaruh kombinasi bahan uji terhadap C. albicans melalui zona hambat yang dibandingkan dengan itraconazole (kontrol positif), ekstrak kulit buah durian, dan akuades (kontrol negatif). Hasil dari penelitian ini menunjukkan pemberian bahan uji kombinasi berpotensi menghambat pertumbuhan C. albicans tanpa dipengaruhi oleh konsentrasi bahan uji. Semakin tinggi konsentrasi kulit buah durian atau itraconazole, maka semakin meningkat pula daya hambat pertumbuhan C. albicans. Kesimpulan dari penelitian ini adalah kombinasi ekstrak kulit buah durian dengan itraconazole berpotensi menghambat pertumbuhan C. albicans in vitro.Kata Kunci: Candida albicans, ekstrak kulit buah durian, itraconazole
... Germ tube formation was induced in a medium containing new born calf serum (10 % v/v) as an inducer of germ tube formation [24] . Overnight culture of C. albicans was diluted in fresh YPD broth and different components were mixed to make the volume 1.0 ml in each tube. ...
Article
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The extracts of Elaeocarpus sphaericus (Roxb.) have shown antimicrobial activities against many pathogenic microbes including fungi. However, the effects of Elaeocarpus sphaericus have not been investigated against key virulence attributes of Candida. In the present study, methanol extract of Elaeocarpus sphaericus leaves was analysed against planktonic cells, hyphal growth, adhesion and biofilm formation of two most important fungal pathogens, Candida albicans and Candida glabrata. Methanol extract of Elaeocarpus sphaericus leaves was prepared by pressurized liquid extraction method. Inhibitory concentration of methanol extract of Elaeocarpus sphaericus leaves for both pathogens was determined by broth microdilution assay. Germ tube formation assay was performed to study the effect of the extract on hyphal transition. Effect of methanol extract of Elaeocarpus sphaericus leaves on adhesion and biofilm formation was investigated in microtiter plate using 2,3-bis(2-methoxy-4-nitro-sulfophenyl)-2H-tetrazolium-5-carboxanilide reduction assay. IC50 values of the extract for Candida albicans and Candida glabrata were found between 0.625-1.25 mg/ml. Serum-induced germ tube development in Candida albicans was inhibited in presence of 5 mg/ml methanol extract. The extract remarkably inhibited in vitro adhesion and biofilm formation by Candida albicans and Candida glabrata in microtiter plates. The results of this study showed anticandida potential of methanol extract of Elaeocarpus sphaericus leaves.
... C. albicans is a pleomorphic opportunistic pathogen and germ tubes formation is a phenotypic characteristic of C. albicans which is essential for virulence [57]. It is well known that C. albicans in germ tube form adhere more efficiently and competently to host cells. ...
Article
The pathogenicity of Candida species in human is dependent on a variety of virulence factor such as adhesion factors, germ tube and hyphal formation, secretion of hydrolytic phospholipases and proteinases and drug resistance biofilm. ZnO NPs have been synthesized by using leaf extract of Crinum latifolium and were characterized by UV–Vis spectrophotometer, FTIR, SEM, EDX and TEM. In this study for the first time, potent inhibitory effects of ZnO NPs on principal virulence factors of Candida albicans and non-albicans such as germ tube formation, secretion of hydrolytic phospholipases and proteinases and biofilm formation has been investigated. ZnO NPs remarkably reduced the germ tube formation of C. albicans at 1 (86.4%), 0.5 (75.0%), 0.25 (61.4%), 0.125 (34.1%) and 0.062 mg/ml (11.4%). ZnO NPs significantly lowered the phospholipase and proteinase secretion by 58.8 and 95.2% at 0.25 mg/ml, respectively. CSLM results showed that ZnO NPs suppressed biofilm formation up to 85% at 0.25 mg/ml. SEM and TEM micrograph showed that ZnO NPs penetrated inside the cell and causes extensive damaged in cell wall and cell membrane. Inhibition of Candida growth and various virulent factors by ZnO NPs provides an insight towards their therapeutic application for the treatment of Candida-associated infections.
... The effect of R. officinalis Linn. essential oil on germ tubes was evaluated as described by Bernardes et al 20 . ...
Article
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The antifungal and anti-germ tube formation activity of Rosmarinus officinalis Linn. essential oil was tested against four Candida strains (C. albicans, C. dubliniensis, C. parapsilosis and C. krusei). Inhibition halo sizes and minimal inhibitory concentrations (MIC) were obtained using radial diffusion and micro dilution tests, respectively. The minimal fungicidal concentration (MFC) was obtained from the MIC assay. Additionally, the effect of the essential oil on germ tube formation in C. albicans and C. dubliniensis was evaluated. The MIC50 ranged from 0.5% to 2%, while the MFC ranged from 1% to 2%. We observed total inhibition of germ tube formation in C. albicans and C. dubliniensis. The R. officinalis Linn. essential oil displayed powerful inhibitory and fungicidal activity against specific Candida strains.
... The ability of the essential oil extracted from Syzygium aromaticum to inhibit the germ tube production by C. albicans has been previously shown by Pinto et al. (2009b). Melaleuca alternifolia, Aloe vera and Streblus asper are some other plants with a potential of controlling germ tube production by C. albicans (Hammer et al., 2008;Bernardes et al., 2012;Taweechaisupapong et al., 2005). Controlling the germ tube formation will make the organism less adherent to host tissues. ...
... The assay was performed by previously described method [30,31]. Briefly, overnight grown C. albicans culture was centrifuged at 3000 rpm for 5 min to pelletize the cells. ...
... As global interest in herbal medicine has grown, plant extracts have been evaluated for their application to preventive and curative programs. Among herbal plants, species of the genus Aloe (Liliaceae) have been extensively studied due to their medicinal properties; Aloe vera, for example, contains many biologically active substances [8] that provide important anti-inflammatory, anti-bacterial, antifungal, hypoglycemic and antidiabetic, immunomodulatory, healing and regenerative functions [9,10,11]. The pharmacodynamic properties of anti-inflammatory and immunoregulatory natural products have been tested in several tissues for their contribution to tissue repair [12]. ...
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Objective: This study aimed to test the calcium hydroxide associated with vehicles Aloe vera, chlorhexidine digluconate (2%) and saline, in inhibiting bacterial growth on Mueller-Hinton agar plates. Methods: The species Staphiloccocus aureus, Streptococcus pyogenes, Escherichia coli and Enterecoccus faecalis were isolated and inoculated in 3 mL of BHI (Brain Heart Infusion). Holes (5 mm diameter) were made in the plates and filled with the test materials. After incubation, readings were taken with a hand lens and a caliper with 0.1 mm accuracy to determine the diameter of the inhibition zone, after 24 and 48 hours. Each experiment was repeated six times, and the average values were obtained. Results: Chlorhexidine digluconate without calcium hydroxide resulted in better inhibition of bacterial growth, followed by the hydroxide pastes evaluated. E. coli strains were the most resistant to the tested compounds, followed by S. pyogenes and S. aureus. There was no statistically significant interaction between the variables. Conclusion: Chlorhexidine digluconate (2%) alone showed the best antimicrobial effectiveness. Aloe vera is a promising vehicle for the calcium hydroxide but more studies should be conducted on herbal medicines in dentistry.
... Effect of alpha-mangostin on germ tube formation was performed based on the method in a previous report [20]. The germ tube formation was induced in a medium containing fetal bovine serum (10% v/v) (Gibco-BRL, Gland Island, NY, USA) as an inducer of germ tube formation. ...
Article
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Objective: Candida-associated denture stomatitis is a very common disease affecting denture wearers. It is characterized by the presence of yeast biofilm on the denture, primarily associated with C. albicans. The investigation of agents that can reduce C. albicans adhesion may represent a significant advancement in the prevention and treatment of this disease. This study aims to investigate the effect of alpha-mangostin on the in vitro adhesion of C. albicans to denture acrylic and germ tube formation by C. albicans and to compare its activity with clotrimazole which is a topical antifungal agent commonly used for the treatment of Candida-associated denture stomatitis. Materials and Methodology: Alpha-mangostin was extracted by thin layer chromatography. The effect of alpha-mangostin on adhesion of C. albicans to denture acrylic was determined by using a colorimetric tetrazolium assay and germ tube formation by C. albicans was determined by using the counting chamber. Results: A significant reduction of C. albicans adhesion to denture acrylic was evident after exposure to 2,000 µg/ml of alpha-mangostin for only 15 min. In addition, the 2,000 µg/ml of the alpha-mangostin-treated C. albicans had a reduced ability for germ tube formation. These inhibitory effects of alpha-mangostin were as effective as clotrimazole. Conclusion: Alpha-mangostin has antifungal property against C. albicans by inhibiting the adhesion to denture acrylic and germ tube formation in vitro. These results suggest the potential application of alpha-mangostin as a topical medication or a natural oral hygiene product for treatment of Candida-associated denture stomatitis.
... The effect of R. officinalis essential oil on germ tube formation was evaluated as described by Bernardes et al 17 . Briefly, germ tube formation was induced in Sabouraud dextrose broth containing fetal bovine serum (10%) and the essential oil from R. officinalis (4%) (assay tube) or broth alone (control tube). ...
Article
Full-text available
The antifungal and anti-germ tube formation activity of Rosmarinus officinalis Linn. essential oil was tested against four Candida strains (C. albicans, C. dubliniensis, C. parapsilosis and C. krusei). Inhibition halo sizes and minimal inhibitory concentrations (MIC) were obtained using radial diffusion and micro dilution tests, respectively. The minimal fungicidal concentration (MFC) was obtained from the MIC assay. Additionally, the effect of the essential oil on germ tube formation in C. albicans and C. dubliniensis was evaluated. The MIC50 ranged from 0.5% to 2%, while the MFC ranged from 1% to 2%. We observed total inhibition of germ tube formation in C. albicans and C. dubliniensis. The R. officinalis Linn. essential oil displayed powerful inhibitory and fungicidal activity against specific Candida strains. Keywords: Candida Species; Rosmarinus officinalis; Essential Oil.
... Thus, due to the fact that the other two hyphal inducers already produced shorter true hyphae in C. albicans, a decrease in hyphal size could not be observed when cells were grown in the presence of the natural product. Although others have found that natural products may impair morphogenesis [34,47,48] , in our study we analyzed a higher number of strains and generated quantitative data of decreased hypha formation, under different bud-to-hyphae transition inducing media. When C. albicans cells suspension were plated on the surface of Spider medium, GlcNac agar and YPD + 20% FBS agar, several phenotypic filamentous colonies were observed. ...
Article
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Background Candida albicans is a diploid yeast that in some circumstances may cause oral or oropharyngeal infections. Yeasts virulence factors contribute for both the maintenance of colonizing strains in addition to damage and cause tissue invasion, thus the establishment of infection occurs. The limited arsenal of antifungal drugs for the treatment of candidiasis turn the investigation of natural products mandatory for the discovery of new targets for antifungal drug development. Therefore, tropical countries emerge as important providers of natural products with potential antimicrobial activity. This study aimed to investigate morphogenesis and secretion of hydrolytic enzymes (phospholipase and proteinase) in the presence of the CE of Eugenia uniflora.Methods The isolates were tested for their ability to form hyphae in both solid and liquid media under three different conditions: YPD¿+¿20% FBS, Spider medium and GlcNac and the ability to secrete phospholipase and proteinase in the presence of 2000 ¿g/mL of E. uniflora.ResultsThe CE of E. uniflora inhibited hypha formation in both liquid and solid media tested. It also impaired hydrolytic enzymes production.Conclusions This was the first study to describe the interaction of a natural product with the full expression of three different factors in C. albicans. E. uniflora may be an alternative therapeutic for oral candidiasis in the future.
... Various studies have been done to assess the antimicrobial activity of Aloe vera on Candida albicans [30]. Aloe vera leaf extracts can inhibit both the germ tube formation and hence the growth of C. albicans [31] . The purified Aloe protein has been found to exhibit potent antifungal activity against Candida paraprilosis, Candida krusei and Candida albicans [32]. ...
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Introduction: Aloe vera is known from centuries as a medicinal plant. It’s a wonder plant with a lot of health benefits and hence often been called the 'natural healer' . It is a tropical plant that flourishes in warm and dry climate and looks like a cactus with fleshy thorny leaves. There are around 400 species of Aloe, but it is the Aloe barbadensis Miller (Aloe vera or " true aloe ") plant which has been used most (found mainly in Asia, Africa and other tropical areas) because of its medicinal uses like moisturizing, anti-inflammatory, antioxidant, anticancer, antibacterial, antiviral and antifungal properties. Medicinal Uses: Aloe vera has its uses in various systemic conditions like skin disorders (e.g. psoriasis), arthritis, asthma, digestive and bowel disorders, diabetes and lowering lipid levels in hyper-lipidemic patients. It has also be used as a detoxifying agent, for topical application of first and second degree burns, as a immune enhancer, in Alzheimer’s disease and in various cosmetic, medical and dental products. Dental Uses: This wonder plant has also been used in dentistry for its beneficial properties in various conditions like lichen planus, apthous stomatitis, oral submucous fibrosis, pulpotomy of primary teeth, prevention of dry sockets, obturation of primary teeth, disinfection of irrigation units, bleeding and painful gums, disinfection of gutta percha cones, burning mouth syndrome and in radiated head and neck cancer patients. The Mini-review Article
... . Further, the immunological efficacy of aloe was reported by a number of investigators, as evidenced by (1) enhancement of the vaccine effects, (2) amelioration of oral ulcers in an animal model, (3) antiinflammatory action on colitis in rats, and (4) reduction of the severity of mucositis associated with cancer therapy (Sun et al., 2011;Park et al., 2011;Worthington et al., 2011). Aloe vera suppressed the growth of Candida albicans significantly, probably due to its active ingredients (Bernardes et al., 2012;Im et al., 2010;Msoffe and Mbilu, 2009). ...
Article
Aloe has been used in versatile herbal medications and nutraceuticals throughout history. Aloe is widely considered to be generally safe for humans and used globally. The effectiveness and pharmacological properties of aloe are dependent upon when the plant is collected. However, little is known about the toxicology of whole-body aloe collected within less than 1 yr. Based upon widespread exposure to aloe, it is important to determine a daily intake level of this chemical to ensure its safety for humans. To determine the no-observed-adverse-effect level (NOAEL) of baby aloe powder (BAP) for clinical application, Sprague-Dawley (SD) rats were treated orally for 4 wk with 4 different concentrations: 0, 0.125, 0.5, and 2 g/kg body weight (bw). In this study, no significant or dose-dependent toxicological effects of BAP were observed in biochemical or hematological parameters, urinalysis, clinical signs, body weight, and food and water consumption. There were changes in some biomarkers in certain treated groups compared to controls; however, all values were within their reference ranges and not dose-dependent. Based on these results, the NOAEL of BAP was estimated to be greater than 2 g/kg bw in male and 2 g/kg bw in female SD rats. Collectively, these data suggest that BAP used in this study did not produce any marked subacute toxic effects up to a maximum concentration of 2 g/kg bw, and thus use in nutraceuticals and in pharmaceutical and cosmetic applications at a concentration of >2 g/kg is warranted.
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Herbal products have been the basis for medical therapy and are noted as a form of alternative medicine. Modern medicine also employs the use of many herbal products for therapeutic purposes. Aloe vera is a medicinal herb whose mucilaginous gel is traditionally used to treat different diseases. It consists of the active compounds which include methylchromones, flavonoids, aloesin, aloe-emodin, sterols, amino acids, aloemannan, aloin, acemannan, aloeride, naftoquinones, saponin and vitamins. Aloe vera toothpaste, consequently, has been developed by the Thailand Institute of Scientific and Technological Research (TISTR) to fulfill a strategy of good oral hygiene. The aim of this study was to investigate the antifungal activity of aloe vera toothpaste against Candida albicans in vitro. Toothpaste containing 10% aqueous extract of the aloe vera leaf was prepared by TISTR. The toothpaste solution was prepared by mixing 0.66 g of toothpaste in 1 mL of sterile deionizing water. The suspensions of 107cfu/mL (equivalent to 0.5 McFarland Standard) of Candida albicans ATCC 10231 and 2 clinical isolates were prepared and added to toothpaste solution. After 50 sec, the final solution was transferred to D/E neutralizing broth and cultured at 37 °C for 24-48 h on Sabouraud dextrose agar. Sterile distilled water was used as a control. Colony forming unit (CFU) was counted after incubation. The result showed that aloe vera toothpaste had a significant inhibitory effect against tested candida species compared with a control. In conclusion, result from the present study is scientific information to prove that aloe vera toothpaste could be assigned as natural toothpaste against candida infection. With proper tooth brushing, it is a simple manner, leading to good oral care.
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Tinea (often known as ringworm) is a fungal infection caused by various fungi like Trichophyton rubrum, T. tonsurans, T. interdigitale, Microsporum canis, and Epidermophyton floccosum. These fungi are known as dermatophyte fungi. Tinea can affect any age group but usually is seen in children. Patients suffering from tinea versicolor are quite common in the occasional rural clinics or even city hospitals of Bangladesh. The rural people of Bangladesh depend on folk medicinal practitioners, otherwise known as Kavirajes for treatment of various ailments, including tinea infections. The main characteristic of Kavirajes is that they depend on administration (topical or oral) of various medicinal plants for treatment of tinea infections. Ethnomedicinal surveys were carried out among the Kavirajes of Bangladesh, as well as tribal medicinal practitioners of more than 20 indigenous communities of the country to document the use of medicinal plants used for treatment of tinea infections by these healers. A total of 26 plants distributed into 23 families were found in the various surveys to be used by the Kavirajes. Although various plant parts were used, leaves constituted the majority of uses. The present review focuses on the medicinal plants used by Kavirajes and tribal medicinal practitioners for treatment of tinea diseases in Bangladesh along with any relevant scientific findings on the anti-fungal activities of the plants, which can validate the plants’ traditional uses. The need for novel, efficacious, safer, and broader spectrum antifungal agents cannot be over emphasized. From this perspective, the above-mentioned medicinal plants may lend themselves to systematic modern scientific explorations in pursuit of novel antifungal agents.
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We describe a case of recurrent Candida glabrata fungemia that became unresponsive to fluconazole treatment. Posttreatment isolates from blood and vaginal cultures of the immunocompetent patient were azole resistant and exhibited upregulated expression of CgCDR1/CgCDR2 efflux pumps compared to the original isolates. Amphotericin B therapy eradicated the infection.
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The emergence of antibiotic resistant bacterial strains is a growing problem and is an important concern for patients, physicians, healthcare managers, and policymakers as it results in poorer health and economic outcomes. This has led to an urgent global call for new antimicrobial drugs, particularly from natural resources. We have been studying the antimicrobial properties of the inner leaf gel component of Aloe barbadensis Miller and have used a number of different, simple in vitro assays to establish a scientific basis for the potential use of Aloe vera on a range of clinically relevant bacteria. The bacteria used include Shigella flexneri, Methicillin-Resistant Staphylococcus aureus (MRSA), Enterobacter cloacae and Enterococcus bovis. In this paper, we compare standard methods recommended by the Clinical and Laboratory Standards Institute (CLSI) with a microtitre assay using a metabolic colour indicator Alamar blue. All the techniques described have shown that Aloe vera has an antimicrobial effect, however, the microtitre assay enables high throughput screening, under similar conditions and is less wasteful of plant material.
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Aqueous or ethanolic extracts of Aloe leaves were examined for antibacterial properties. The crude extrudes strongly stimulated bacterial growth. Separation of various fractions by thin layer chromatography (TLC) resulted in a fraction which inhibited the growth of Bacillus subtilis. A concomitant examination of protein and nucleic acid synthesis in B. subtilis in the presence of the inhibitory compound indicated that the plant extract inhibits primarily nucleic acid synthesis, after which protein synthesis is also inhibited. The inhibitor seemed to be present in all examined Aloe species but at different concentrations. On a dry weight basis, the inhibitory effect was equally distributed between the skin and the gel fraction.
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We review the scientific literature regarding the aloe vera plant and its products. Aloe vera is known to contain several pharmacologically active ingredients, including a carboxypeptidase that inactivates bradykinin in vitro, salicylates, and a substance(s) that inhibits thromboxane formation in vivo. Scientific studies exist that support an antibacterial and antifungal effect for substance(s) in aloe vera. Studies and case reports provide support for the use of aloe vera in the treatment of radiation ulcers and stasis ulcers in man and burn and frostbite injuries in animals. The evidence for a potential beneficial effect associated with the use of aloe vera is sufficient to warrant the design and implementation of well-controlled clinical trials. 27 references.
Article
Fungal infections in the oral cavity are mainly caused by C. albicans, but other Candida species are also frequently identified. They are increasing in prevalence, especially in denture-wearers and aging people, and may lead to invasive infections, which have a high mortality rate. Attachment to mucosal tissues and to abiotic surfaces and the formation of biofilms are crucial steps for Candida survival and proliferation in the oral cavity. Candida species possess a wide arsenal of glycoproteins located at the exterior side of the cell wall, many of which play a determining role in these steps. In addition, C. albicans secretes signaling molecules that inhibit the yeast-to-hypha transition and biofilm formation. In vivo, Candida species are members of mixed biofilms, and subject to various antagonistic and synergistic interactions, which are beginning to be explored. We believe that these new insights will allow for more efficacious treatments of fungal oral infections. For example, the use of signaling molecules that inhibit biofilm formation should be considered. In addition, cell-wall biosynthetic enzymes, wall cross-linking enzymes, and wall proteins, which include adhesins, proteins involved in biofilm formation, fungal-bacterial interactions, and competition for surface colonization sites, offer a wide range of potential targets for therapeutic intervention.
Article
Administration of air under the skin produced a pouch wall that closely resembled a synovium in that the inner lining was made up of macrophages and fibroblasts. Administration of 1% carrageenan directly into the 7-day-old air pouch produced an inflammation characterized by an increased number of mast cells in pouch fluid as well as an increase in wall vascularity. A punch biopsy weight of the pouch wall did not reveal an increase in 1% carrageenan-treated animals. However, a 10% Aloe vera treatment of carrageenan-inflamed synovial pouches reduced the vascularity 50% and the number of mast cells in synovial fluid 48%. The pouch wall punch biopsy weight was increased by A. vera, which was verified by histologic examination of the inner synovial lining. Aloe vera stimulated the synovial-like membrane, as evidenced by an increased number of fibroblasts, suggesting that A. vera stimulated fibroblasts for growth and repair of the synovial model. The synovial air pouch can be used to study simultaneously the acute anti-inflammatory and fibroblast stimulating activities of A. vera.
Article
In early 1990 fluconazole was introduced as a prophylactic antifungal agent after bone marrow transplantation. During the same year Candida krusei emerged as the chief candida pathogen among patients with bone marrow transplants. To determine whether there was a correlation between the introduction of fluconazole and the increased incidence of C. krusei, we conducted a retrospective study based on the medical, mycologic, and autopsy records of all adult inpatients who had undergone bone marrow transplantation (n = 296) or who had leukemia (n = 167) at the study center during 1989 and 1990. The 84 patients who received antifungal prophylaxis with fluconazole had a sevenfold greater frequency of C. krusei infection than the 335 patients who did not receive fluconazole (8.3 percent vs. 1.2 percent, P = 0.002), despite having a lower frequency of disseminated C. albicans and C. tropicalis infections (0 vs. 6.0 percent, P = 0.02). Ten of the 11 C. krusei infections were controlled by a combination of amphotericin B and flucytosine. Colonization by C. krusei was found in 40.5 percent of the patients who received fluconazole but in only 16.7 percent of those who did not receive it (P less than 0.0001). Colonization was independently associated with the prophylactic use of both fluconazole (odds ratio, 3.50; P less than 0.001) and norfloxacin (odds ratio, 2.53; P = 0.04). C. krusei was not susceptible to fluconazole in vitro. In patients at high risk for disseminated candida infections, suppression of bacterial flora and the more common candida pathogens may permit some less pathogenic, but natively resistant candida species, such as C. krusei, to emerge as systemic pathogens.
Article
The antimicrobial properties of three glycols, - propylene glycol, hexylene glycol, and 1,3-butylene glycol - against Candida albicans, Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pyogenes A, Streptococcus mitis, and E. coli were studied in vitro. Within 20 h, 10% and 30% hexylene glycol in fresh tryptic soy broth were able to kill all the micro-organisms listed above. Five percent hexylene glycol showed some antimicrobial properties but the 1% agent had no effect. Thirty percent 1,3-butylene glycol and 30% propylene glycol were approximately as effective as 10% HG. The results speak in favour of using hexylene glycol in cosmetic and dermatological vehicles instead of propylene glycol and 1,3-butylene glycol.
Article
Article
More than 25,000 primary bloodstream infections (BSIs) were identified by 124 National Nosocomial Infections Surveillance System hospitals performing hospital-wide surveillance during the 10-year period 1980-1989. These hospitals reported 6,729 hospital-months of data, during which time approximately 9 million patients were discharged. BSI rates by hospital stratum (based on bed size and teaching affiliation) and pathogen groups were calculated. In 1989, the overall BSI rates for small (less than 200 beds) nonteaching, large nonteaching, small (less than 500 beds) teaching, and large teaching hospitals were 1.3, 2.5, 3.8, and 6.5 BSIs per 1,000 discharges, respectively. Over the period 1980-1989, significant increases (p less than 0.0001) were observed within each hospital stratum, in the overall BSI rate and the BSI rate due to each of the following pathogen groups: coagulase-negative staphylococci, Staphylococcus aureus, enterococci, and Candida species. In contrast, the BSI rate due to gram-negative bacilli remained stable over the decade, in all strata. Except for small nonteaching hospitals, the greatest increase in BSI rates was observed in coagulase-negative staphylococci (the percentage increase ranged between 424% and 754%), followed by Candida species (219-487%). In small nonteaching hospitals, the greatest increase was for S. aureus (283%), followed by enterococci (169%) and coagulase-negative staphylococci (161%). Our analysis documents the emergence over the last decade of coagulase-negative staphylococci as one of the most frequently occurring pathogens in BSI.
Article
An Aloe vera extract was prepared with 50% ethanol. The resultant supernatant and precipitate were tested for anti-inflammatory activity using the croton oil-induced ear-swelling assay. The supernatant fraction decreased inflammation, when applied topically, by 29.2%, and the precipitate decreased inflammation by 12.1%. The authors have shown that the anti-inflammatory activity (inhibitory system) resides in the supernatant of a 50% ethanol extract.
Article
The mechanism of action of aloe-emodin-9-anthrone, a decomposition product of barbaloin, in causing a significant increase in the water content of the rat large intestine, was investigated. Aloe-emodin-9-anthrone inhibited rat colonic Na+, K(+)-adenosine triphosphatase (ATPase) in vitro, and increased the paracellular permeability across the rat colonic mucosa in vivo. Therefore, it seemed that the increase in water content of the rat large intestine produced by aloe-emodin-9-anthrone was due to both inhibition of absorption and stimulation of secretion without stimulation of peristalsis. Furthermore, pretreatment with loperamide, an antidiarrheal agent, completely prevented the increase of paracellular permeability induced by aloe-emodin-9-anthrone but did not completely reduce the concomitant increase in residual fluid volume. These findings suggest that aloe-emodin-9-anthrone has multiple mechanisms of action involved in the increase of water content in the rat large intestine.
Article
We review the scientific literature regarding the aloe vera plant and its products. Aloe vera is known to contain several pharmacologically active ingredients, including a carboxypeptidase that inactivates bradykinin in vitro, salicylates, and a substance(s) that inhibits thromboxane formation in vivo. Scientific studies exist that support an antibacterial and antifungal effect for substance(s) in aloe vera. Studies and case reports provide support for the use of aloe vera in the treatment of radiation ulcers and stasis ulcers in man and burn and frostbite injuries in animals. The evidence for a potential beneficial effect associated with the use of aloe vera is sufficient to warrant the design and implementation of well-controlled clinical trials.
Article
Our experience in the treatment of chronic mucocutaneous candidiasis with ketoconazole is reviewed. Of 21 patients, 15 have evidence of deficient cellular immunity and eight have endocrine abnormalities. Six patients had concurrent dermatophytosis or chromomycosis. All patients responded to treatment. Mucosal lesions improved in 6.7 +/- 0.5 days and cutaneous lesions responded to 22.7 +/- 5.1 days. The responses by infected nails were more variable (mean response time 92.4 +/- 14.4 days). Concurrent dermatophytoses did not prolong response times. Adverse effects were infrequent: one patient had drug-induced hepatitis and two patients became hypertensive. The relationship of hypertension to ketoconazole treatment is unclear. One patient was able to remain in remission after treatment was discontinued. Two patients had relapses while on treatment. Candida albicans isolated from these patients was highly resistant to ketoconazole in vitro. We conclude that ketoconazole is an effective and well-tolerated drug for the treatment of the infectious component of chronic mucocutaneous candidiasis.
Article
The antimycotic activity of ethane-1,2-diol, propane-1,2-diol, butane-1,3-diol, pentane-1,5-diol, and hexane-2,5-diol in vitro against Pityrosporum orbiculare, Candida albicans, Trichophyton rubrum, T. mentagrophytes var. interdigitale and Epidermophyton floccosum was studied. Ethane-1,2-diol had the lowest activity (MIC of 40–100 g 1-1), and hexane-2,5-diol the highest activity (MIC of 10–40g 1-1). Among the higher diols there can be both effective antifungal agents and substances with a lower risk of allergic and irritative skin reactions than propane-1,2-diol.
Article
Currently, about 180 hospitals participate in the National Nosocomial Infections Surveillance (NNIS) system. From January 1980 through April 1990, 27,200 fungal isolates causing nosocomial infections were reported from these hospitals; Candida species accounted for 19,621 (72.1%) of these isolates. Immunocompromised patients are at particularly high risk for candidemia. In patients with acute lymphocytic leukemia, treatment with vancomycin and/or imipenem appears to be an independent risk factor for candidemia; colonization of stool by Candida species may be another important predisposing factor in these patients. Rapid detection of invasive candidemia in these high-risk patients is particularly important to the improvement of rates of survival. Methods for rapid detection, such as the measurement of mannan (the major cell-wall polysaccharide of Candida), may be useful for diagnosing invasive candidiasis and for monitoring the response of this infection to antifungal therapy. Further studies of risk factors and the development of new methods for rapid diagnosis and monitoring should help decrease the morbidity and mortality associated with nosocomial fungal infections.
Article
Aloe-emodin-9-anthrone(AE-anthrone), produced from barbaloin in the rat large intestine, caused not only an increase in the intestinal water content but also stimulated mucus secretion. This might play an important role in the occurrence of diarrhea. It was demonstrated that the amount of AE-anthrone produced in the rat large intestine(maximal amount: 568 micrograms/rat at 4 h after injection) was enough to cause both of these effects, which were observed following intracecal administration of barbaloin (31.1 mg/kg). These results together with our previous data, which showed a relationship between increase in the intestinal water content and the stimulation of peristalsis, confirm that AE-anthrone is the principal agent responsible for the cathartic effect of barbaloin. We also propose that the increase in water content is a more important factor than stimulation of peristalsis in the induction of diarrhea by barbaloin.
Article
A broth macrodilution technique, which was performed by following the recommendations provided by the National Committee for Clinical Laboratory Standards (document M27-P), was applied to study the in vitro activity of itraconazole against fluconazole-susceptible and -resistant Candida albicans isolates from the oral cavities of 100 patients infected with human immunodeficiency virus. The in vitro data demonstrated that itraconazole had good activity against the tested isolates; for 90% of all strains of C. albicans, MICs were 1 microgram/ml, and only one isolate was highly resistant to this triazole (MIC, > 16 micrograms/ml). However, the itraconazole MICs for the fluconazole-susceptible isolates were significantly lower than those for the fluconazole-resistant isolates; the MICs for 50 and 90% of the isolates tested were < or = 0.03 and 0.25 microgram/ml, respectively, for the fluconazole-susceptible isolates and 0.5 and 1 microgram/ml, respectively, for the fluconazole-resistant isolates (P = 0.00001). Our findings could be of clinical relevance because human immunodeficiency virus-infected patients who fail fluconazole therapy for oral and/or esophageal candidiasis may require itraconazole at doses higher than those used in standard therapy.
Article
Charcoal transport, as an indicator of the degree of peristalsis, and water content in the large intestine after the intracaecal administration of barbaloin, were measured simultaneously in the same rat. Charcoal transport was significantly accelerated at both 3.5 and 6.5 h after the administration of barbaloin. At 6.5 h, diarrhea instead of normal faeces was observed. Moreover, at 1 h before the acceleration of charcoal transport, a marked increase in the relative water content of the large intestine was observed. It appears that the increase in water content of the large intestine induced by barbaloin precedes the stimulation of peristalsis, attended by diarrhea. Therefore, it is suggested that the increase in water content is a more important factor than the stimulation of peristalsis in the diarrhea induced by barbaloin.
Article
The antimicrobial activities of 23 extracts of 12 Cuban plant species reported in traditional medicine were tested. The agar diffusion method was used to assess the activity against four bacteria and one yeast: Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa and Candida albicans. The results, evaluated as the diameter of the inhibition zone of microbial growth, showed that nine extracts were active against Gram-positive bacteria but only two of these proved to be also active against Gram-negative bacteria. None of the extracts inhibited the growth of the yeast. The most susceptible bacterium was Staphylococcus aureus and the best antibacterial activity was shown by Schinus terebenthifolius.
Article
Candida albicans and Saccharomyces cerevisiae switch from a yeast to a filamentous form. In Saccharomyces, this switch is controlled by two regulatory proteins, Ste12p and Phd1p. Single-mutant strains, ste12/ste12 or phd1/phd1, are partially defective, whereas the ste12/ste12 phd1/phd1 double mutant is completely defective in filamentous growth and is noninvasive. The equivalent cph1/cph1 efg1/efg1 double mutant in Candida (Cph1p is the Ste12p homolog and Efg1p is the Phd1p homolog) is also defective in filamentous growth, unable to form hyphae or pseudohyphae in response to many stimuli, including serum or macrophages. This Candida cph1/cph1 efg1/efg1 double mutant, locked in the yeast form, is avirulent in a mouse model.
Article
Different extracts of both fresh and dry leaves of Aloe eru A. Berger, A. vera L. Webb & Berth and A. arborescens Mill. were screened for their antifungal activity against Aspergillus niger, Cladosporium herbarum and Fusarium moniliforme. The toxicity of the isolated pure components were evaluated on the tested fungi. A comparative chromatographic study was performed to differentiate between natural components existing in various fractions and extracts of Aloe species and specific spray reagents were used for the detection of anthraquinones in the isolated components.
Article
In this report, we describe a patient with recurrent episodes of oral candidosis who finally suffered from fluconazole-refractory oral and oesophageal candidosis. The patient was monitored for 4 years until his death from AIDS. During the observation period, persistent colonization with both Candida albicans and Candida dubliniensis was observed. From the appearance of the first episode of oral candidosis, the patient was treated with fluconazole for 18 months. The infection became unresponsive to fluconazole 400 mg/day. In vitro susceptibility testing revealed the development of resistance to fluconazole in C. albicans and C. dubliniensis. Molecular typing confirmed the persistence of the same C. albicans and C. dubliniensis strains which developed resistance after up to 3 years of asymptomatic colonization. This observation demonstrates that Candida spp. other than C. albicans may develop resistance to fluconazole in a patient who is repeatedly exposed to the drug.
Article
Candidiasis is a common infection of the skin, oral cavity and esophagus, gastrointestinal tract, vagina and vascular system of humans. Although most infections occur in patients who are immunocompromised or debilitated in some other way, the organism most often responsible for disease, Candida albicans, expresses several virulence factors that contribute to pathogenesis. These factors include host recognition biomolecules (adhesins), morphogenesis (the reversible transition between unicellular yeast cells and filamentous, growth forms), secreted aspartyl proteases and phospholipases. Additionally, 'phenotypic switching' is accompanied by changes in antigen expression, colony morphology and tissue affinities in C. albicans and several other Candida spp. Switching might provide cells with a flexibility that results in the adaptation of the organism to the hostile conditions imposed not only by the host but also by the physician treating the infection.
Article
The ethnoveterinary use of Aloe species extract in free-range local chickens against fowl typhoid was investigated. Five-months-old local chickens, free of antibodies against fowl typhoid were used. The chickens were randomly assorted into five groups including pretreated and infected (G1, n=21), infected and untreated (G2, n=21), infected and treated (G3, n=21), untreated and uninfected (G4, n=10) and treated uninfected (G5, n=10). Groups 1, 2 and 3 were inoculated with 5.0 x 10(8) c.f.u/ml of Salmonella gallinarum, following which the chickens were monitored for 15 days. There was a delay on the occurrence of the clinical signs and reduced severity of the disease in the Aloe treated chickens (G1 and G3). The mortality rates were 23.8% (5/21) in G1 (pretreated and infected), 42.8% (9/21) in G2 (infected and untreated) and 14.2% (3/21) in G3 (infected and treated). Antibody levels were raised among the infected and untreated group (G2) while they remained relatively low in the Aloe treated groups (G1 and G3). However, there was a sharp increase in the levels of interleukin 6 (IL-6) in the Aloe treated groups (G1 and G3) as compared to the untreated group (G2) until day 9 post-infection. The results of this work indicate that the extract of Aloe secundiflora may be used in the control of fowl typhoid in chickens. Studies to determine the active ingredients of the plant extract are in progress.
Article
Two replicate experiments were carried out to verify the efficacy of Aloe species (Aloaceae) as used for the control of Newcastle disease (ND) in rural poultry in free-range systems among several communities in Tanzania. Four months old local chickens free of Newcastle disease antibodies were used. Following inoculation with ND virus, body weights, clinical signs, antibody levels and mortality were monitored. Results showed that there was reduced mortality rate and the severity of clinical signs during the acute phase of the infection in Aloe treated chickens compared with the non-treated ones. However, there was no significant effect of the Aloe on the antibody levels that were attributed to the recovery of the surviving chickens. The findings of this study suggest that Aloe secundiflora could be a potential candidate on the management of Newcastle disease in chickens. Further studies are in progress to identify the active ingredients of A. secundiflora against Newcastle disease virus.
Article
Aloe vera fresh leaves hydroalcoholic plant extract was tested against the mycelial growth of Botrytis gladiolorum, Fusarium oxysporum f.sp. gladioli, Heterosporium pruneti and Penicillium gladioli on Czapek-agar medium. The minimum fungicidal concentration (MFC) varied between 80 and 100 microl/ml, depending on the fungal species.
Evaluation butylene glycol in vitro
  • Waihenya Rk
  • Mtambo Mm
  • Nkwengulila
22 Waihenya RK, Mtambo MM, Nkwengulila G. Evaluation butylene glycol in vitro. Acta Derm Venereol 1991; 71: 148–50.
Aloe vera: its chemical and therapeutic properties
  • Shelton
Shelton RM. Aloe vera: its chemical and therapeutic properties. Int J Dermatol 1991; 30: 679–83.
Antifungal effects of different plant extracts and their major components of selected aloe species
  • Ali
Partial purification and some properties of the antibacterial compounds from Aloe vera
  • Levien