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1.
Biomédica (Bogotá) ; 43(Supl. 1): 156-169, ago. 2023. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1533896

RESUMO

Introducción. Los géneros Alternaria y Fusarium contienen especies patógenas para los humanos y los cultivos. Para su control, se han utilizado diversos antifúngicos. Sin embargo, su uso desmedido ha contribuido al desarrollo de agentes patógenos resistentes. Una alternativa para buscar y desarrollar nuevos agentes antimicóticos son los aceites esenciales y sus componentes principales, los cuales poseen diversas actividades biológicas de interés para la medicina y en la preservación de alimentos. Objetivo. Evaluar in vitro e in silico las actividades antifúngicas de terpenoides contra Alternaria alternata y Fusarium oxysporum. Materiales y métodos. Se evaluaron in vitro las concentraciones inhibitorias mínimas y las concentraciones fungicidas mínimas de 27 constituyentes de aceites esenciales contra A. alternata y F. oxysporum. Además, mediante algoritmos genéticos, se crearon modelos cuantitativos de la relación estructura-actividad para determinar las propiedades estructurales y fisicoquímicas relacionadas con la actividad antifúngica. Resultados. Los compuestos evaluados mostraron ser antifúngicos activos. El timol fue el compuesto con mayor actividad, con un valor de concentración inhibitoria mínima de 91.6 ± 28.8 pg/ml, tanto para Alternarla alternata como para Fusarium oxysporum. Los modelos cuantitativos de la relación estructura-actividad incluyeron la avidez por los lípidos y los fenoles como los principales grupos funcionales que contribuyen en la actividad antifúngica. Conclusión. Los terpenoides poseen actividades antifúngicas relevantes para ser incorporados en el estudio de la química medicinal. La inclusión de pruebas in silico a la evaluación in vitro es una herramienta útil para la búsqueda y el diseño racional de derivados terpénicos como posibles agentes antifúngicos.


Introduction. Fungal genera Alternaría and Fusarium include human and plant pathogenic species. Several antifungals have been used for their control, hut excessive use has contributed to resistance development in pathogens. An alternative to searching for and developing new antifungal agents is using essential oils and their main components, which have biological activities of interest in medicine and food production. Objective. To evaluate in vitro and in silico the antifungal activities of terpenoids against Alternaria alternata and Fusarium oxysporum. Materials and methods. The minimum inhibitory concentration and minimum fungicidal concentration values of 27 constituents of essential oils used against Alternaria alternata and Fusarium oxysporum were evaluated in vitro. In addition, using genetic algorithms, quantitative models of the structure-activity relationship were used to identify the structural and physicochemical properties related to antifungal activity. Results. The evaluated compounds proved to be effective antifungals. Thymol was the most active with a minimum inhibitory concentration of 91.6 ± 28.8 pg/ml for A. alternata and F. oxysporum. Quantitative structure-activity relationship models revealed the octanol-water cleavage ratio as the molecular property, and the phenols as the main functional group contributing to antifungal activity. Conclusion. Terpenoids exhibit relevant antifungal activities that should be incorporated into the study of medicinal chemistry. Inclusion of in silico assays in the in vitro evaluation is a valuable tool in the search for and rational design of terpene derivatives as new potential antifungal agents.


Assuntos
Óleos Voláteis , Alternaria , Fusarium , Relação Quantitativa Estrutura-Atividade
2.
China Journal of Chinese Materia Medica ; (24): 2732-2738, 2023.
Artigo em Chinês | WPRIM | ID: wpr-981376

RESUMO

In Zherong county, Fujian province, the black spot of Pseudostellaria heterophylla often breaks out in the rainy season from April to June every year. As one of the main leaf diseases of P. heterophylla, black spot seriously affects the yield and quality of the medicinal material. To identify and characterize the pathogens causing black spot, we isolated the pathogens, identified them as a species of Alternaria according to Koch's postulates, and then tested their pathogenicity and biological characteristics. The results showed that the pathogens causing P. heterophylla black spot were A. gaisen, as evidenced by the similar colony morphology, spore characteristics, sporulation phenotype, and the same clade with A. gaisen on the phylogenetic tree(the maximum likelihood support rate of 100% and the Bayesian posterior probability of 1.00) built based on the tandem sequences of ITS, tef1, gapdh, endoPG, Alta1, OPA10-2, and KOG1077. The optimum conditions for mycelial growth of the pathogen were 25 ℃, pH 5-8, and 24 h dark culture. The lethal conditions for mycelia and spores were both treatment at 50 ℃ for 10 min. We reported for the first time the A. gaisen-caused black spot of P. heterophylla. The results could provide a theoretical basis for the diagnosis and control of P. heterophylla leaf spot diseases.


Assuntos
Teorema de Bayes , Filogenia , Caryophyllaceae , Alternaria , Micélio
3.
Chinese Journal of Dermatology ; (12): 996-999, 2022.
Artigo em Chinês | WPRIM | ID: wpr-957774

RESUMO

Objective:To analyze clinical manifestations, histopathological and pathogenic fungus characteristics as well as treatment of 3 cases of disseminated cutaneous alternariosis caused by Alternaria. Methods:Clinical data were collected from 3 cases of disseminated cutaneous alternariosis caused by Alternaria, who were diagnosed in Department of Dermatology, Xijing Hospital from 2019 to 2021, and clinical and histopathological features, fungal culture, strain identification and treatment results were retrospectively analyzed. Results:The 3 patients were aged 55, 41 and 46 years respectively, including 1 male and 2 females. Two patients were previously diagnosed with nephrotic syndrome and 1 with systemic lupus erythematosus. All the patients had a history of taking glucocorticoids and tacrolimus for different durations, and experienced chronic infections. Histopathological examination with hematoxylin and eosin (HE) staining showed double-contour thick-walled spores and knot-shaped thick-walled septal hyphae, but no melanin in skin lesions. Sequencing of the fungal internal transcribed spacer region confirmed that 2 cases were infected with Alternaria alternate, and 1 with Alternaria infectoria. Fungal culture at different temperatures showed that the growth ability of Alternaria markedly decreased at the temperature over 35 ℃. To treat these patients, the dose of tacrolimus was reduced to less than 1/3 of the standard dose, or tacrolimus was switched to other immunosuppressants, and systemic antifungal therapy was also given at the same time. After 7-month treatment, good clinical outcomes were achieved in the 3 patients. Conclusion:Disseminated cutaneous alternariosis is characterized by bilateral hematogenous dissemination and lymphatic distribution in unilateral limbs, and the skin lesions are characterized by verrucous plaques covered with scabs, nodules and/or sinuses.

4.
Malaysian Journal of Microbiology ; : 163-169, 2022.
Artigo em Inglês | WPRIM | ID: wpr-977519

RESUMO

Aims@#Potatoes are considered one of the most strategic vegetable crops all over the world. Alternaria alternata has recently contaminated certain potatoes farms in different regions in Egypt. Among thirteen samples from fifteen regions were studied in a precedent study. Our study was aimed to investigate the effect of Bacillus thuringiensis subsp. Kurosaki suspension on inhibiting the growth of the three tested isolates of A. alternata and minimizing their mycotoxins production in vitro using three isolates with three levels of highly, moderate and low pathogenicity with unequal amounts of dual mycotoxins production.@*Methodology and results@#Three isolates of A. alternata from three regions, Kom Hamada (KH3), Alamin (Alam1) and Nobaria (NO3), which were determined as a producer of tenuazonic acid (TeA) and alternariol monomethyl ether (AME) toxins. Bacillus thuringiensis (Bt) use as commercial fungicide was applied with three suspension concentrations (75, 150 and 300 μg/mL) as inhibitor for the two mycotoxins. Our results illustrated that the three tested isolates recorded high TeA and AME inhibition efficacies by increasing the Bt suspension concentration. The highest inhibitory concentration of Bt was at concentration 75 μg/mL for isolated from Nobaria third region (NO3) and Alam1 it was (99.83 and 99.74%) for mycotoxin (AME) while, TeA mycotoxin had the most inhibition percentage (99.58%) at concentration 150 μg/mL for the isolate (NO3).@*Conclusion, significance and impact of study@#The preliminary results of the study suggest that B. thuringiensis spores’ suspension with different concentrations can be used as anti-mycotoxigenic agents to inhibit the (TeA) and (AME) mycotoxins produced by Alternaria alternata.


Assuntos
Bacillus thuringiensis , Solanum tuberosum
5.
Acta Pharmaceutica Sinica ; (12): 2120-2125, 2022.
Artigo em Chinês | WPRIM | ID: wpr-936566

RESUMO

To study the chemical constituents from the the deep-sea fungus Alternaria sp. F49. Seven compounds were isolated from the EtOAc extract by using silica gel, Sephadex LH-20, ODS and HPLC methods. Based on the spectroscopic analysis, their structures were identified as (8R)-5-O-methyl-orcinotriol (1), orcinotriol (2), α-acetylorcinol (3), 3'-hydroxyalternariol 5-O-methyl ether (4), altenusiol (5), altenusin (6), and 5'-methoxy-6-methyl-biphenyl-3,4,3'-triol (7). (8R)-5-O-Methyl-orcinotriol (1) is a new phenolic compound which has never been reported in the literature. Compounds 4-7 showed strong DPPH free radical scavenging activity; whereas compounds 1-7 showed strong ABTS free radical scavenging activity.

6.
China Journal of Chinese Materia Medica ; (24): 1215-1221, 2022.
Artigo em Chinês | WPRIM | ID: wpr-928045

RESUMO

In Hezhang county, Guizhou province, black spot tends to occur to Aconitum carmichaelii in the hot rainy summer, with the incidence up to 50%-70%, seriously impacting the yield and quality of the medicinal material. Thus, this study aims to clarify the pathogen and the occurrence characteristics. To be specific, the pathogen was isolated and identified according to Koch's postulates and the pathogenicity and biological characteristics were determined. In addition, the sensitivity of the pathogen to four microbial fungicides, four botanical fungicides, and five chemical fungicides was determined with the mycelium growth rate method for the purpose of screening out optimal fungicides. The pathogen was identified as Alternaria alternate, as evidenced by the similar colony morphology and microscopic characteristics and 99.55%-100% similarity in sequences of rDNA-ITS, LSU, 18S, and TEF of the two. The optimum growth conditions for A. alternata were 28 ℃, pH 8, and continuous darkness. Bacillus subtilis had strong inhibitory effect on the pathogen, and the inhibition rate was more than 90% when the concentration was 1 mg·L~(-1). In addition, difenoconazole and quinoline copper can also control the pathogen, with median effective concentration(EC_(50)) of 2.92 and 9.02 mg·L~(-1), respectively. This study lays a theoretical basis for the field control of black spot in A. carmichaelii.


Assuntos
Aconitum , Alternaria , Fungicidas Industriais/farmacologia , Micélio
7.
Braz. arch. biol. technol ; 65: e22200749, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1364465

RESUMO

Abstract Endophytic bacteria from weed are emerging as valuable alternatives for biochemical pesticides in sustainable agriculture. This study aims to discover the antagonistic effects of some endophytic bacteria isolated from weed (Lactuca indica) against A. alternata, a casual of stem end rot disease of pitaya. A total of 14 endophytic bacteria were isolated and four of them presented in vitro antagonistic activity against A. alternata. Of four, strain L115 significantly inhibited the pathogenic growth with a mean inhibition diameter of 12.67 ± 0.02 mm, while the other three (strain L110, L111, and L114) showed a weak inhibition. The results indicated that strain L115 could belong to the Bacillaceae family while the other three (strain L110, L111, and L114) had characteristics of the Pseudomonadaceae family. Interestingly, strain L115 showed positive results for phosphate solubilization, indole acetic acid (IAA), and biofilm production, whereas three other strains presented weak capabilities for phosphate solubilization, biofilm production and IAA production. In addition, the filtrate of strain L115 presented antifungal activity on biocontrol tests in vitro. Especially, strain L115 significantly increased seedling biomass of pitaya and tomato compared to the control. Hence, these results suggest strain L115 has the potential to be used as biocontrol agents against A. alternata. More studies should be done in the future to evaluate their efficiency in field conditions.

8.
Journal of Pharmaceutical Practice ; (6): 542-548, 2021.
Artigo em Chinês | WPRIM | ID: wpr-904757

RESUMO

Objective To investigate the taxonomic structure and diversity of endophytic fungi from Cynanchum bungei Decne., explore the potential microbial resources and functions and provide the theoretical basis for new antitumor endophytic fungi. Methods The diversities of endophytic fungi community in different tissues, species and habitats were analyzed with traditional endophytic bacteria separation method and 18sRNA high-throughput sequencing technology. MTT assay was used to detect the cytotoxic activity of endophytic fungi from Radix Polygoni multiflori. Results 90 strains of endophytic fungi were isolated and identified from roots, stems, and leaves of C. bungei. Among them, Fusarium and Alternaria were the dominant genera. There were 8, 9 and 13 genera from roots, stems and leaves of C. bungei respectively. Among which Alternaria and Colletotrichum were the common genera in different tissues. Further studies showed that 13 endophytic fungi of C.bungei had good anti-tumor activity in vitro, accounting for 14.4% of the total genera. Among them, A. tenuissima LTJ2 and A. alternata LTJ6 had significant anti-tumor activity. Conclusion The endophytic fungi in Cynanchum bungei Decne. have rich diversity. Some strains have significant anti-tumor activity,which can be potential resources for the development of new antitumor agents.

9.
Chinese Journal of Natural Medicines (English Ed.) ; (6): 700-705, 2021.
Artigo em Inglês | WPRIM | ID: wpr-888801

RESUMO

Biotransformation of α-asarone by Alternaria longipes CGMCC 3.2875 yielded two pairs of new neolignans, (+) (7S, 8S, 7'S, 8'R) iso-magnosalicin (1a)/(-) (7R, 8R, 7'R, 8'S) iso-magnosalicin (1b) and (+) (7R, 8R, 7'S, 8'R) magnosalicin (2a)/(-) (7S, 8S, 7'R, 8'S) magnosalicin (2b), and four known metabolites, (±) acoraminol A (3), (±) acoraminol B (4), asaraldehyde (5), and 2, 4, 5-trimethoxybenzoic acid (6). Their structures, including absolute configurations, were determined by extensive analysis of NMR spectra, X-ray crystallography, and quantum chemical ECD calculations. The cytotoxic activity and Aβ

10.
Acta Pharmaceutica Sinica ; (12): 2248-2251, 2021.
Artigo em Chinês | WPRIM | ID: wpr-887051

RESUMO

Six compounds were isolated from the crude extract of the liquid culture of Alternaria sp. W-1 by silica gel column chromatography, Sephadex LH-20 gel column chromatography, and HPLC. They were identified as 6-iso-tricycloalternarene 6a (1), tricycloalternarene 6a (2), tricycloalternarene B (3), uracil (4), 5-methyluracil (5), and lumichrome (6) through HR-MS, NMR and literature comparison. 6-iso-Tricycloalternarene 6a (1) is a new compound which has never been reported in the literature. In cytotoxicity assay, compounds 1-3 showed weak inhibition activity to human hepatoma cell line SMMC-7721 and human gastric cell line SGC-7901.

11.
Rev. Asoc. Colomb. Cien. Biol. (En línea) ; 2(33): 75-82, 2021. graf, ilus, tab
Artigo em Inglês | LILACS, COLNAL | ID: biblio-1379300

RESUMO

Introducción: Alternaria spp y Candida spp. son hongos patógenos de ambientes interiores como la casa, la oficina, el aula, etc., causan enfermedades como asma crónica e infecciones sistémicas en individuos inmunodeprimidos a través de la secreción de diversas sustancias tóxicas. Los ambientadores a base de productos químicos disponibles comercialmente que se utilizan para controlar la carga de hongos en el ambiente interior no son beneficiosos para la salud humana. Objetivo: proporcionar una alternativa viable en forma de enfoque basado en nanopartículas para el manejo de hongos transmitidos por el aire. Metodología: aislamiento, identificación microscópica y bioquímica de hongos de interior; Síntesis de nanopartículas de azufre (SNP) mediadas por Azadirachta indica, su detección y caracterización; y evaluación in vitro de SNP contra hongos aislados presentes en el ambiente interior. Resultado: Los hongos aislados se identificaron como especies de Alternaria spp y Candida spp. Los SNP mostraron máximos de absorbancia a 291 nm. El análisis NTA mostró un tamaño medio de 188,4 nm y un potencial zeta de -4,94 mV, lo que representa una síntesis de SNP estables. El patrón XRD confirmó la naturaleza cristalina cúbica centrada en la cara de los SNP. El espectro FTIR representó la presencia de compuestos polihidroxilo, nitrilo, ceto, aromáticos y carboxílicos que estabilizaron los SNP. Los ensayos antifúngicos demostraron la actividad significativa de los SNP formulados y del ambientador infundido con aceite de eucalipto. Conclusión: Los SNP mediados por A. indica se pueden aplicar en la formulación y fabricación de un ambientador ecológico para el manejo de hongos patógenos de interior como Alternaria spp y Candida spp.


Introduction: Alternaria spp. and Candida spp. are the main fungal pathogen of indoor environment like house, office, classroom, etc. These may cause various diseases and infections like systemic infections, or chronic asthma in immunocompromised individuals through secretion of various toxic substances. Chemical-based commercially available room fresheners used to control the fungal load of indoor environment are not beneficial to human health. Objective: was to provide viable alternative in the form of nanoparticle-based approach for the management of air-borne fungi. Methodology: The present study primarily focuses on the isolation, microscopic and biochemical identification of indoor fungi; Azadirachta indica-mediated sulphur nanoparticles (SNPs) synthesis, their detection and characterization; and in vitro assessment of SNPs against isolated fungi present in indoor environment. Result: The isolated fungi were identified as Alternaria spp and Candida spp. The SNPs showed absorbance maxima at 291 nm. NTA analysis showed average size of 188.4 nm, and zeta potential of -4.94 mV which represented synthesis of stable SNPs. XRD pattern confirmed the face centered cubic, crystalline nature of SNPs. FTIR spectrum depicted the presence of polyhydroxyl, nitrile, keto, aromatic and carboxylic compounds which stabilized the SNPs. The antifungal assays demonstrated the significant activity of the formulated SNPs and eucalyptus oil infused air freshener. Conclusion: It can be concluded that A. indica-mediated SNPs can be applied in the formulation and manufacture of an ecofriendly air freshener for the management of indoor fungal pathogens like Alternaria spp. and Candida spp.


Assuntos
Nanopartículas , Antifúngicos , Candida , Alternaria
12.
Artigo | IMSEAR | ID: sea-204895

RESUMO

Sesame is one of the most important oilseed crops in India due to mainly its high quality seed oil and antioxidant properties. Occurrence of foliar diseases, like Alternaria leaf spot and Cercospora leaf spot has become a major constraint in recent years for successful and profitable cultivation of sesame. Field experiments were conducted with sesame var. savitri in a factorial randomized block design with three different dates of sowing with 15 days interval and two different plant protection situations (Protected i.e., treated with disease control protocols and unprotected i.e., control), replicated four times, during two consecutive summer seasons of 2018 and 2019 at Agricultural Experimental Farm, Institute of Agricultural Science, University of Calcutta, Baruipur, South 24 Parganas. The diseases incidence was estimated and correlated with the weather parameters. The average of weather parameters viz., maximum temperature, minimum temperature, relative humidity (morning), relative humidity (evening) and rainfall prior to seven days of disease appearance were considered for study the correlation between the weather factors and the disease. In 2018, disease incidences of the plants shown at third date of sowing (26th April, 2018) in both the protected and unprotected plots had significant (P=.05) but negative correlation with maximum temperature. For plants sown at first date of sowing (27th March, 2018) in 2018 had disease incidences significantly (P=.05) and positively correlated with minimum temperature. However, in 2019, except for the relation between disease incidences in the unprotected plots and maximum temperature, all other disease-temperature correlations were non-significant. Disease incidences were positively and significantly correlated with relative humidity (both morning and evening) in all dates of sowing irrespective of experimental years, except with morning relative humidity at first date of sowing in first year. Total rainfall was positively and significantly correlated with disease incidences at all dates of sowing in 2018; however, such relation was non-significant in 2019.

13.
Int J Pharm Pharm Sci ; 2020 Mar; 12(3): 42-48
Artigo | IMSEAR | ID: sea-206061

RESUMO

Objective: Endophytes are widely spread in the plant kingdom and represent a very promising source of biologically active natural products. The medicinal plant Bidens bipinnata Lin. (Asteraceae) which is known for its anti-inflammatory, antifungal and antitumor effects has been chosen for the investigation of its endophyte to search for bioactive metabolites. Methods: An endophytic Alternaria alternata species was isolated from the leaves of the plant B. bipinnata Lin. To investigate the metabolic profile of this endophytic fungus it was cultivated in several culture media as static and shaken culture. The antimicrobial and cytotoxic activities of the ethyl acetate extracts of the fungus were examined. Extracts exhibiting highest antimicrobial activities in agar diffusion assay and cytotoxicity against HeLa cancer cell line were subjected to activity-guided chromatographic fractionation for the identification of bioactive metabolites. A cytotoxic assay was performed on the isolated compounds against HeLa cancer cell lines as well as cytostatic activity tests against HUVEC and K-562 cell lines. Results: Chromatographic fractionation resulted in the isolation and identification of alternariol and tentoxin from the extract of the fungus cultivated in medium M5 while sterigmatocystin was isolated in addition to alternariol and tentoxin from the extract of the fungus grown in medium M25. Both alternariol and sterigmatocystin proved to be of moderate cytotoxicity and weak cytostatic activity with alternariol showing higher cytotoxic activity than sterigmatocystin. Highest cytotoxicity against HeLa cell lines was observed for tentoxin with a CC50 of 22.5 µg/ml. Conclusion: This study presents the isolation and identification of the bioactive metabolites alternariol, sterigmatocystin and tentoxin from the endophyte A. alternata in addition to the antifungal activity of the strain extract as well as the cytotoxic and cytostatic activities of the isolated metabolites against HeLa, HUVEC and K-562 cell lines, respectively.

14.
J Environ Biol ; 2019 Nov; 40(6): 1137-1144
Artigo | IMSEAR | ID: sea-214449

RESUMO

Aim: Alternaria blight caused by Alternaria lini is one of the major diseases of linseed which severely affects the yield and productivity. Here, we utilizes F2 mapping population derived from a resistant (JRF-4) and a susceptible (Chambal) genotypes of linseed and SSRs to identify the markers associated with Alternaria blight resistance using bulk segregant analysis approach. Methodology: A population consisting of 154 F2 individuals was developed from the cross between JRF-4 (resistant) and Chambal (susceptible). All 154 F2 individuals were screened with 100 polymorphic SSRs to identify extreme phenotype. Two bulk of extremes phenotypes (disease resistant and disease susceptible) from F2 mapping population were used for the bulked segregant analysis. The SSR primers that distinguished the parental lines were used to amplify the DNA from two bulks and banding pattern was observed to identify the SSRs that can differentiate the resistant and susceptible phenotypes bulk for Alternaria blight. Markers validation was carried out by amplifying DNA from individual plants of each bulk. Results: Out of 100, only 10 markers showed polymorphism among the bulks and of which only three markers viz., LUSc 898_3_12, Lu 2472 and Lu 3078 were able to differentiate the disease resistant and susceptible individuals from F2 population. Further, single marker linear regression approach was used to validate the association of selected polymorphic markers with the disease. The markers LUSc 898_3_12 and Lu 2472 showed significant regression which confirmed their linkage with Alternaria blight resistance. Interpretation: The two markers having significant regression can be used for diseases resistance breeding during marker assisted selection.

15.
Artigo | IMSEAR | ID: sea-209851

RESUMO

This study was conducted to investigate the causal agent of brown leaf spot (BLS) of cassava in Kenyanfields. Infected cassava leaf samples showing BLS disease symptoms were collected from Kenya Agriculturaland Livestock Research Organization (KALRO) experimental fields in central and western Kenya. Fungalpathogens associated with the disease were isolated from the cassava leaf samples on potato dextrose agaramended with antibiotics. Three fungal isolates, belonging to the genera Colletotrichum, Alternaria, andCladosporium, were identified as the causative agents of BLS with relative prevalence of 41%, 24%, and 18%,respectively. Susceptible cassava variety TME 204 was inoculated with single and combinations of purifiedisolates of the three pathogens in a randomized design in the greenhouse. The combination of the three isolatesresulted in typical BLS symptoms as observed in the field. The findings of this study would help to understandthe disease, contribute to its better management, and eventually alleviate food insecurity, especially in theregions where cassava is a major staple food and a source of income.

16.
Indian J Ophthalmol ; 2019 Jul; 67(7): 1048-1053
Artigo | IMSEAR | ID: sea-197332

RESUMO

Purpose: The aim of the study is to identify risk factors, clinical characteristics, causative fungi, and treatment outcome of dematiaceous fungal keratitis in North India. Methods: Consecutive cases of culture-proven dematiaceous fungal keratitis between January 2012 and June 2017 were retrieved from the medical record department. Risk factors, clinical signs, and outcome were registered. Results: Eighty-three patients were included. Identified dematiaceous fungal organism were Curvularia sp. (n = 55/83; 66.3%), Alternaria sp. (n = 12/83; 14.5%), Ulocladium sp. (n = 5/83; 6%), Bipolaris sp. (n = 5/83; 6.1%), Scedosporium sp. (n = 3/83; 3.6%), Acremonium sp. (n = 2/83; 2.4%), and Epicoccum sp. (n = 1/83; 1.2%). Male preponderance was reported. The most common predisposing factor was corneal trauma (67.4%). In cases associated with corneal trauma due to vegetative matter, sugarcane was the most common cause. In all, 89% of the patients were more than 30 years of age. The median infiltrate size was 8 mm2. The median time of antifungal therapy was 4.2 weeks (interquartile range [IQR]: 1-25 weeks). Complications were seen in 14 (n = 14/65; 21.5%) patients. Complete resolution of dematiaceous fungal keratitis was present in 27 (n = 27/65; 41.5%) eyes. Conclusion: Curvularia sp. and Alternaria sp. were the predominant pathogenic genera causing dematiaceous fungal keratitis. Among the causative fungi, infections due to Scedosporium sp. were associated with the worst outcomes. Ulocladium sp. and Epicoccum sp. were also identified. Both the species are not reported previously as a causal organism of dematiaceous fungal keratitis from North India.

17.
Artigo | IMSEAR | ID: sea-200766

RESUMO

Evaluation of the relative efficacy of powdered leaf extracts of Aloe vera(Linn) and Aloe schweinfurthii(Baker) in the control of some plant pathogens was undertaken in this work. Antimicrobial activities ofthe extracts obtained using cold water, hot water and ethanol were tested against four fungal spp., namely, Alternaria solani,Colletotrichum lindemuthianum, Sclerotium rolfsiiand Trichophyton rubrum. The phytochemical screening of the leaf extracts of the two aloe species revealed the presence of bioactive compounds such as alkaloids, tannins, saponins, flavonoids, cardiac glycosides, phytates and oxalates. The extracts were observed to exhibit varying inhibitory effects on the selected fungi. Ethanolic extract of A. veraat 50mg/ml and 100mg/ml had the greatest impact on A. solaniand C. lindemuthianum respectively.Similarly, cold water extract of A. schweinfurthiiat 100mg/ml was the most effective against S. rolfsiiandT. rubrum.However, hot water extract of A. vera wasleast effective against C. lindemuthianum. Also, the efficacy of cold water extract of A. schweinfurthii at 50mg/mlwas very low against T. rubrumand A. solani. The hot water extract of A. schweinfurthii at 20mg/ml also showed the least effect against S. rolfsii. Consequently, extracts from both Aloe species can be recommended in the management of the four fungal pathogens evaluated in this study. It is hoped that in no distant future, botanical fungicides would be developed from the two Aloe species

18.
Braz. j. biol ; 79(1): 127-132, Jan.-Mar 2019. tab
Artigo em Inglês | LILACS | ID: biblio-983990

RESUMO

Abstract In recent years, natural products with antifungal and antioxidant activities are being increasingly researched for a more sustainable alternative to the chemicals currently used for the same purpose. The plant pathogenic fungus Alternaria alternata is a causative agent of diseases in citrus, leading to huge economic losses. Antioxidants are important for the production of medicines for various diseases that may be related to the presence of free radicals, such as cancer, and in the cosmetic industry as an anti-aging agent and the food industry as preservatives. This study evaluated the antifungal and antioxidant potential of extracts of mature leaves of Myrcia splendens, a tree species that occurs in the Brazilian Cerrado. The antioxidant potential was analyzed by an assay of 1,1-diphenyl-2-picrylhydrazyl radical-scavenging method, and the antifungal activity was assessed through the evaluation of mycelial growth. Majority of the extracts exhibited a strong antioxidant activity, especially the acetonic extract (4A). The antioxidant activity may be related to the presence of phenolic compounds. However, the extracts showed no inhibitory activity of mycelial growth of the fungus tested, with the exception of dichloromethanic extract (2B), which had an inhibitory effect (10.2%) at the end of testing.


Resumo A busca de produtos naturais com atividades antifúngica e antioxidante tem crescido nos últimos anos como alternativa mais sustentável para os produtos químicos atualmente usados para estas funções. O fungo fitopatogênico Alternaria alternata é agente causador de doenças nos citros, levando a grandes perdas econômicas. Substâncias antioxidantes são importantes tanto para a produção de medicamentos para diversas doenças que podem estar relacionadas à presença de radicais livres, como o câncer, bem como para a indústria cosmética, como agentes anti-envelhecimento e para a indústria alimentícia, como conservantes. Este trabalho avaliou o potencial antifúngico dos extratos de folhas maduras de Myrcia splendens , uma espécie arbórea que ocorre no cerrado brasileiro. O potencial antioxidante foi analisado por meio de ensaio da capacidade sequestrante do radical 1,1-diphenyl-2-picrylhydrazyl e o antifúngico, por meio da avaliação do crescimento micelial. A maioria dos extratos apresentou atividade antioxidante muito forte, especialmente o extrato acetônico (4A). A atividade antioxidante pode ser relacionada a presença de compostos fenólicos. Por outro lado, os extratos não apresentaram atividade inibitória do crescimento micelial do fungo testado, com exceção do extrato diclorometânico (2B), que foi o único que teve efeito inibitório (10,2%) ao final do teste.


Assuntos
Myrtaceae/química , Antifúngicos/farmacologia , Antioxidantes/farmacologia , Brasil , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Folhas de Planta/química , Antifúngicos/isolamento & purificação , Antioxidantes/isolamento & purificação
19.
Chinese Traditional and Herbal Drugs ; (24): 1061-1065, 2019.
Artigo em Chinês | WPRIM | ID: wpr-851292

RESUMO

Objective This study focused on the secondary metabolites of endophytic fungus Alternaria alternate in Paeonia lactiflora. Methods Compounds were isolated from the EtOAc extract by chromatography technology and their structures were elucidated on the basis of comprehensive spectroscopic analysis. Results A total of 15 compounds were isolated and their structures were identified as methyl 4-acetamido-3-hydroxybenzoate (1), (E)-methyl5-hydroxy-3-methylpent-2-eno (2), isobenzofuranone A (3), 4-hydroxyacetophenone (4), 6-hydroxy-isosclerone (5), talarojlavone (6), 7-hydroxy-2-hydroxymethyl-5-methyl-4H-chromen-4-one (7), alternarienonic acid (8), 7-hydroxy-2,5-dimethyl-4H-1-benzopyran-4-one (9), 5-hydroxy-epialtenuene (10), alternariol (11), methyl 3-hydroxybenzoate (12), stemphyperylenol (13), altenusin (14), and altenuene (15). Conclusion Compounds 1, 3, 5-10, 12, and 13 are isolated from Alternaria alternatefor the first time.

20.
Chinese Archives of Otolaryngology-Head and Neck Surgery ; (12): 42-44, 2019.
Artigo em Chinês | WPRIM | ID: wpr-742788

RESUMO

OBJECTIVE To varify the difference of serum specific IgE levels in different ages and gender inpatients with Aspergillus fumigatus or Alternaria alternate induced allergic rhinitis. METHODS In this study, 85 patients with Aspergillus fumigatus or Alternaria alternate induced allergic rhinitis were included. sIgE tests was done by Immuno CAP 250TM System(Thermo Fisher Scientific, Uppsala, Sweden). RESULTS Mean level of aspergillus fumigatus sIgE was significantly lower than Alternaria alternate(P<0.05), single or dual fungi allergy show no impact on this difference. sIgE level showed positive correlation with age in Aspergillus fumigatus group(P <0.05), while negative in Alternaria alternate group(P <0.05). CONCLUSION Aspergillus fumigatus and Alternaria alternate are mostly common fungi allergens, sIgE detection of those two fungi are important for diagnosis of fungi induced allergic rhinitis and other respiratory diseases in people with different ages.

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