Tephrosia toxicaria (Sw.) Pers. extracts: Screening by examining aedicidal action under laboratory and field conditions along with its antioxidant, antileishmanial, and antimicrobial activities.

An increase in the incidence of arboviral, microbial and parasitic infections, and to disorders related to oxidative stress has encouraged the development of adjuvant therapies based on natural formulations, such as those involving plant extracts. Thus, to expand the repertoire of the available therapeutic options, this study aimed to describe the versatility of Tephrosia toxicaria (Sw.) (Pers., 1807) extracts for the control of arbovirus vectors, as well as their antioxidant, antileishmanial, and antimicrobial potential. Among the aqueous and hydroethanolic extracts obtained, the hydroethanolic extract from roots (RHA) was identified as the most active larvicide extract demonstrating, respectively, the lowest lethal concentration (mg/mL) for 50%, 90% and 99% of Aedes aegypti (L., 1762) and Aedes albopictus (S., 1894) larvae, observed at 24 h (0.33, 0.84 and 1.80; 0.32, 0.70 and 1.32) and 48 h (0.17, 0.51 and 1.22; 0.26, 0.47 and 0.78) post-exposure. Field assays revealed that RHA (0.84 mg/mL) is a potential oviposition deterrent, reducing egg-laying by approximately 90%. RHA (0.1 mg/mL) also exhibited antioxidant activity for the following tests: total antioxidant capacity (286.86 mg AAE/g), iron (87.16%) and copper (25.64%) chelation, and superoxide scavenging (10%). In the cell culture assays, RHA (0.1 mg/mL) promoted regeneration of metabolic activity (92% cell viability) in cells exposed to oxidative stress. Furthermore, RHA displayed weak antileishmanial activity (IC50 = 3.53 mg/mL) against Leishmania amazonensis and not exhibit antimicrobial activity. The extraction favored the concentration of carbohydrates in RHA, in addition to lectins and protease inhibitors, with molecular masses estimated between 10 and 24 kDa. Cytotoxicity and phytotoxicity analyses of RHA suggested its biosecurity. Thus, RHA is a multivalent extract with insecticide and antioxidant properties at low and safe concentrations. However, others studies on its indirect toxic effects are ongoing to ensure the complete safety of RHA.

Antifungal activity and antidiarrheal activity via antimotility mechanisms of (-)-fenchone in experimental models.

BACKGROUND: (-)-Fenchone is a bicyclic monoterpene present in essential oils of plant species, such as Foeniculum vulgare and Peumus boldus, used to treatment of gastrointestinal diseases. Pharmacological studies report its anti-inflammatory, antioxidant, and antinociceptive activity. AIM: To investigate antidiarrheal activity related to gastrointestinal motility, intestinal secretion and antimicrobial activity. METHODS: A castor oil-induced diarrhea model was used to evaluate antidiarrheal activity. Intestinal transit and gastric emptying protocols were used to assess a possible antimotility effect. Muscarinic receptors, presynaptic α2-adrenergic and tissue adrenergic receptors, KATP channels, nitric oxide were investigated to uncover antimotility mechanisms of action and castor oil-induced enteropooling to elucidate antisecretory mechanisms. The antimicrobial activity was evaluated in the minimum inhibitory concentration model, the fractional inhibitory concentration index using the (-)-fenchone association method with standard antifungal agents. RESULTS: (-)-Fenchone (75, 150 and 300 mg/kg) showed antidiarrheal activity, with a significant decrease in the evacuation index. This activity is possibly related to a percentage of reduced intestinal transit (75, 150 and 300 mg/kg). The antimotility effect of (-)-fenchone decreased in the presence of pilocarpine, yohimbine, propranolol, L-NG-nitroarginine methyl ester or glibenclamide. In the enteropooling model, no reduction in intestinal fluid weight was observed. (-)- Fenchone did not show antibacterial activity; on the other hand, inhibits the growth of strains of fungi with a minimum fungicide concentration of 32 µg/mL. However, when it was associated with amphotericin B, no synergism was observed. CONCLUSION: The antidiarrheal effect of (-)-fenchone in this study involves antimotility effect and not involve antisecretory mechanisms. (-)-Fenchone presents antifungal activity; however, it did not show antibacterial activity.

Antifungal activity study of the monoterpene thymol against Cryptococcus neoformans.

Cryptococcus neoformans is a yeast fungus, which causes cryptococcosis, triggered by basidiospore inhalation and consequent dissemination to the central nervous system. In this study, we analyzed the antifungal action of thymol against 10 clinical strains of C. neoformans and analyzed the interaction of this monoterpene with sterols. The MICs of thymol ranged from 20 to 51 µg/ml, while the MFC values varied between 40 and 101 µg/ml. For the strains ICB-2601 and LM-39, in the presence of ergosterol, the MIC of thymol was 64 µg/ml, and in the presence of cholesterol, its MIC was 32 µg/ml. Based on the results, thymol presents antifungal action and seems to interact with ergosterol, but not with cholesterol. Complementary studies are needed to analyze its full effects.

Phytoconstituents from Sidastrum micranthum (A. St.-Hil.) Fryxell (Malvaceae) and antimicrobial activity of pheophytin a

abstract Sidastrum micranthum (A. St.-Hil.) Fryxell, a member of the Malvaceae family, is called malva preta in Brazil. As this species is commonly used to treat bronchitis, cough, and asthma, better knowledge of its chemical compounds is important. The phytochemical study of its hexane extract, using chromatographic techniques, led to isolation of six compounds: the triterpene isoarborinol, a mixture of sitosterol and stigmasterol, sitosterol-3-O-β-D-glucopyranoside, pheophytin a, and 132-hydroxy-(132-S)-pheophytin a. Structural identification of these compounds was carried out using spectroscopic methods such as IR and 1D and 2D NMR (HOMOCOSY, HMQC, HMBC, and NOESY). Compounds isolated from S. micranthum were screened for their in vitro antifungal and antibacterial activity against twenty fungal and bacterial standard strains. Pheophytin a exhibited antimicrobial action against all microorganisms tested.

resumo Sidastrum micranthum (A. St.-Hil.) Fryxell, pertencente à família Malvaceae, é conhecida no Brasil como "malva preta". A espécie é popularmente usada contra bronquite, tosse e asma, mostrando a relevância de conhecer melhor sua composição química. O estudo fitoquímico do extrato hexânico da espécie, utilizando técnicas cromatográficas, conduziu ao isolamento de seis compostos: o triterpeno isoarborinol, mistura de sitosterol e estigmasterol, sitosterol-3-O-β-D-glicopiranosídeo, feofitina a e de 132-hidroxi-(132-S)-feofitina a. A identificação estrutural destes compostos foi realizada com base em métodos espectroscópicos, tais como IV, RMN 1D e 2D (HOMOCOSY, HMQC, HMBC e NOESY). As substâncias isoladas de Sidastrum micranthum foram avaliadas quanto às suas atividades antimicrobianas in vitro, contra vinte cepas fúngicas e bacterianas. A feofitina a mostrou ação antimicrobiana contra todos os microrganismos testados.

Does scientific evidence for the use of natural products in the treatment of oral candidiasis exist? A systematic review.

In view of the limitations of antifungal agents used in the treatment of oral candidiasis and the wide variety of natural products that have been studied as treatment of this disease, this systematic literature review proposed to evaluate whether scientific evidence attesting to the efficacy of natural products in the treatment of this disease exists. A systematic search in PubMed, MEDLINE, SciELO, Lilacs, and Cochrane Library databases was accomplished using the associations among the keywords Candida albicans, phytotherapy, biological products, denture stomatitis, and oral candidiasis in both English and Portuguese. Four independent observers evaluated the methodological quality of the resulting articles. Three studies were included for detailed analysis and evaluated according to the analysis protocol based on the CONSORT (Consolidated Standards of Reporting Trials) 2010 statement. The tested products were different in all studies. Two studies mentioned random samples, but no study described the sample allocation. No study mentioned sample calculations, a prior pilot study, or examiner calibration, and only one trial reported sample losses. Differences between the tested products and the methodological designs among these studies did not allow the existence of scientific evidence related to the effectiveness of these products for the proposed subjects to be confirmed.

Evaluation of Antifungal Activity and Mechanism of Action of Citral against Candida albicans.

Candida albicans is a yeast that commensally inhabits the human body and can cause opportunistic or pathogenic infections. Objective. To investigate the antifungal activity of citral against C. albicans. Methodology. The minimum inhibitory concentration (MIC) and the minimum fungicidal concentration (MFC) were determined by the broth microdilution techniques. We also investigated possible citral action on cell walls (0.8 M sorbitol), cell membranes (citral to ergosterol binding), the time-kill curve, and biological activity on the yeast's morphology. Results. The MIC and MFC of citral were, respectively, 64 µg/mL and 256 µg/mL. Involvement with the cell wall and ergosterol binding were excluded as possible mechanisms of action. In the morphological interference assay, it was observed that the product inhibited pseudohyphae and chlamydoconidia formation. The MIC and the MFC of citral required only 4 hours of exposure to effectively kill 99.9% of the inoculum. Conclusion. Citral showed in vitro antifungal potential against strains of C. albicans. Citral's mechanism of action does not involve the cell wall or ergosterol, and further study is needed to completely describe its effects before being used in the future as a component of new antifungals.

Phenolic profile, antioxidant activity and palynological analysis of stingless bee honey from Amazonas, Northern Brazil.

In this study honey samples produced by Melipona (Michmelia) seminigra merrillae, collected in seven counties distributed in the central and southern region of Amazonas state in Brazil, were analysed for their botanical origin, content and profile of phenolic compounds, and antioxidant and antimicrobial activities. Twenty-two pollen types were identified. The total phenolic content ranged from 17 to 66 mg GAE/g of extract; the highest contents were found in honeys produced from pollen types such as Clidemia and Myrcia. The antioxidant activity was higher in the samples that contained higher quantities of phenolic compounds. In relation to the antibacterial activity, samples CAD3, CAD4 and SAD3 presented the best results. Fourteen phenolic compounds were determined. Among them, we identified the flavonoid taxifolin, which has not previously been described in honeys from stingless bees, and we report the identification of catechol in Brazilian honey samples for the first time.

Treatment of pityriasis versicolor with topical application of essential oil of Cymbopogon citratus (DC) Stapf - therapeutic pilot study.

BACKGROUND: Pityriasis versicolor is a fungal infection caused by Malassezia spp. that has frequent relapses. OBJECTIVES: The main objective of this research was to perform phase I and II clinical studies, using formulations containing essential oil of Cymbopogon citratus in patients with pityriasis versicolor. METHODS: Phase I study included twenty volunteers to ascertain the safety of the formulations. In phase II, 47 volunteers randomly received essential oil formulations at 1.25 µL/mL concentration, for forty days. The shampoo should be applied three times a week and the cream twice a day. A control group in phase II, consisting of 29 volunteers, received the same formulations but with 2% ketoconazole as the active ingredient. RESULTS: No significant adverse events were observed in volunteers during Phase I. In Phase II, 30 (63.83%) volunteers using essential oil and 18 (62.07%) using ketoconazole remained until the end of the study. We observed a predominance of lesions in disseminated form, with M. sympodialis detected as the predominant agent identified in cultures. After 40 days of treatment, the rate of mycological cure was 60% (p <0.05) for the group treated with essential oil of C. citratus and over 80% (p <0.05) for the group treated with ketoconazole formulations. CONCLUSIONS: Notwithstanding the safety and antifungal effects observed in this study after application of formulations containing the essential oil of C. citratus, further studies with larger populations should be performed to confirm the actual potential of these formulations in the treatment of patients with Pityriasis versicolor.

Treatment of pityriasis versicolor with topical application of essential oil of Cymbopogon citratus (DC) Stapf - therapeutic pilot study / Tratamento de pitiríase versicolor com aplicação tópica do óleo essencial de Cymbopogon citratus (DC) Stapf - estudo terapêutico piloto

BACKGROUND: Pityriasis versicolor is a fungal infection caused by Malassezia spp. that has frequent relapses. OBJECTIVES: The main objective of this research was to perform phase I and II clinical studies, using formulations containing essential oil of Cymbopogon citratus in patients with pityriasis versicolor. METHODS: Phase I study included twenty volunteers to ascertain the safety of the formulations. In phase II, 47 volunteers randomly received essential oil formulations at 1.25 μL/mL concentration, for forty days. The shampoo should be applied three times a week and the cream twice a day. A control group in phase II, consisting of 29 volunteers, received the same formulations but with 2% ketoconazole as the active ingredient. RESULTS: No significant adverse events were observed in volunteers during Phase I. In Phase II, 30 (63.83%) volunteers using essential oil and 18 (62.07%) using ketoconazole remained until the end of the study. We observed a predominance of lesions in disseminated form, with M. sympodialis detected as the predominant agent identified in cultures. After 40 days of treatment, the rate of mycological cure was 60% (p <0.05) for the group treated with essential oil of C. citratus and over 80% (p <0.05) for the group treated with ketoconazole formulations. CONCLUSIONS: Notwithstanding the safety and antifungal effects observed in this study after application of formulations containing the essential oil of C. citratus, further studies with larger populations should be performed to confirm the actual potential of these formulations in the treatment of patients with Pityriasis versicolor. .

FUNDAMENTOS: Pitiríase versicolor é uma micose causada pela Malassezia spp., e que apresenta frequentes recidivas. OBJETIVOS: Este trabalho objetivou realizar estudos clínicos de fase I e II, para essa patologia, com óleo essencial de Cymbopogon citratus. MÉTODOS: Na fase I, participaram vinte voluntários para averiguar a segurança das formulações. Na fase II, 47 voluntários receberam as formulações do óleo essencial a 1,25 μL/mL, as quais deveriam ser utilizadas por quarenta dias, sendo o xampu três vezes por semana e o creme duas vezes ao dia. Um grupo controle na fase II, constituído por 29 voluntários recebeu as mesmas formulações, com cetoconazol a 2%. RESULTADOS: Verificada a segurança das formulações com a finalização da fase I, onde nenhuma reação adversa significativa foi observada nos indivíduos sadios, conduziu-se a fase II. Nesta segunda fase, 30 (63,83%) voluntários utilizando óleo essencial e 18 (62,07%) cetoconazol permaneceram até o final do estudo. Observaram-se nos pacientes com pitiríase versicolor predomínio de lesões na forma disseminada e M. sympodialis foi o agente predominante identificado em cultura. Após 40 dias de tratamento, obteve-se um percentual de cura micológica de 60% (p < 0,05) para o grupo tratado com óleo essencial de C. citratus e superior a 80% (p < 0,05) para o grupo tratado com cetoconazol. CONCLUSÕES: Apesar da segurança e efeito antifúngico observados após aplicação das formulações contendo óleo essencial de C. citratus, outros estudos com maior número de portadores de pitiríase versicolor precisam ser realizados para confirmar o real potencial destas f...

Effect of Schinus terebinthifolius on Candida albicans growth kinetics, cell wall formation and micromorphology.

OBJECTIVE: To evaluate the anti-fungal activity of a tincture from Schinus terebinthifolius (Brazilian pepper tree) on Candida albicans (ATCC 289065), a micro-organism associated with fungal infections of the oral cavity. MATERIALS AND METHODS: Minimum Inhibitory Concentration (MIC) and Minimum Fungicidal Concentration (MFC) were determined through microdilution technique, as well as the microbial growth curve of C. albicans promoted by S. terebinthifolius. In addition, this study investigated a possible activity of the product on the fungal cell wall and its biological activity on fungal morphology. Nystatin was used as control and all tests were performed in triplicate. RESULTS: S. terebinthifolius showed MIC of 312.5 µg/mL and MFC of 2500 µg/mL upon the strain tested, while Nystatin showed MIC and MFC of 6.25 µg/mL. As regards the microbial growth curve, S. terebinthifolius was able to significantly reduce the number of CFU/mL when compared to growth control until the time of 60 min. In the times 120 and 180 min there was no statistically significant difference between the growth control and the experimental product. S. terebinthifolius possibly acts on the fungal cell wall, once the sorbitol test indicated a MIC of 1250 µg/mL. In the fungal morphology, a reduction was observed of pseudo-hyphae, chlamydoconidia and blastoconidia in the presence of the experimental product. CONCLUSION: S. terebinthifolius showed anti-fungal activity against C. albicans, inhibiting, probably, the fungal cell wall formation.

Increasing antibiotic activity against a multidrug-resistant Acinetobacter spp by essential oils of Citrus limon and Cinnamomum zeylanicum.

The genus Acinetobacter has gained importance in recent years due to involvement in serious infections and antimicrobial resistance. Many plants have been evaluated not only for direct antimicrobial activity, but also as resistance modifying agents. The Essential oil of Citrus limon (EOCL) addition at 156.25 µgmL(-1) (MIC/8) sub-inhibitory concentration in the growth medium led to MIC decrease for amikacin, imipenem and meropenem. The Essential oil of Cinnamomum zeylanicum (EOCZ) addition at 78.125 µg mL(-1) (MIC/8) sub-inhibitory concentrations in the growth medium caused drastic MIC reduction of amikacin. Results of combining antibiotics and essential oils had shown us a synergistic effect with both essential oils/amikacin combinations. An additive effect was observed with the combinations of both essential oils and gentamicin. The results of this study suggest that essential oil of C. limon and C. zeylanicum may suppress the growth of Acinetobacter species and could be a source of metabolites with antibacterial modifying activity.

Screening da Atividade Antifúngica de Óleos Essenciais sobre Cepas de Candida / Screening of Essential Oils Antifungal Activity on Candida Strains

Objetivo: O propósito desse estudo foi identificar a atividade antifúngica de óleos essenciais sobre cepas de Candida envolvidas com infecções da cavidade bucal. Método: Foram avaliados óleos essenciais obtidos a partir das seguintes espécies vegetais: Citrus reticulata (Tangerina Cravo); Citrus aurantifolia (Limão Tahiti); Cinnamomum zeylanicum (Canela); Matricaria chamomilla (Camomila Azul); Mentha piperita (Menta); Eugenia uniflora (Pitanga) e Zingiber officinale (Gengibre). A determinação da atividade antifúngica foi realizada utilizando a técnica de difusão em meio de cultura sólido, onde discos de papel de filtro foram embebidos nos óleos e colocados em placas de Petri contendo agar Sabouraud Dextrose inoculado com cepas de Candida albicans e C. tropicalis. Também foi observada a concentração inibitória mínima a partir do método da microdiluição. Os ensaios foram realizados em duplicata. Resultados: Foi observada expressiva atividade antifúngica dos óleos essenciais de C. zeylanicum, C. aurantifolia e M. piperita, que apresentaram diâmetros de halos de inibição de crescimento microbiano de até, respectivamente, 48 mm, 30 mm e 19 mm. Ainda foi possível identificar que 66,7% das cepas ensaiadas mostraram-se resistentes aos óleos essenciais de C. reticulata, M. chamomilla, E. uniflora e Z. officinale. O C. zeylanicum e nistatina apresentaram, respectivamente, CIMs de 312 µg mL-1 e 32 µg mL-1. Conclusão: Os óleos essenciais avaliados apresentam atividade antifúngica, sendo os melhores resultados encontrados para C. zeylanicum. Sugere-se a realização de outros ensaios para avaliação de atividade anti-Candida desse óleo essencial, que pode representar possível agente terapêutico no tratamento de infecções fúngicas da cavidade bucal

Objective: The purpose of this study was to identify the antifungal activity of essential oils on Candida strains involved in oral cavity infections. Methods: essential oils obtained from the following species were evaluated: Citrus reticulata (Cravo Tangerine) Citrus aurantifolia (Tahiti Lime), Cinnamomum zeylanicum (Cinnamon), Matricaria chamomilla (Blue Chamomile), Mentha piperita (Mint), Eugenia uniflora (Pitanga) and Zingiber officinale (Ginger). The determination of antifungal activity was performed using the diffusion technique on solid medium, where filter paper discs were soaked in oils and placed in Petri dishes containing Sabouraud dextrose agar inoculated with strains of Candida albicans and C. tropicalis. It was also observed the minimum inhibitory concentration from the microdilution method. Tests were performed in duplicate. Results: We observed significant antifungal activity of essential oils ofC. zeylanicum, C. aurantifolia and M. piperita, which had halos of microbial growth inhibition with diameters up to 48 mm, 30 mm and 19 mm, respectively. Still, it was possible to identify that 66.7% of strains tested were resistant to essential oils of C. reticulata, M. chamomilla, E. uniflora and Z. officinale. C. zeylanicum and nystatin showed µg mL-1 and 32 µg mL-1 MIC, respectively. Conclusion: The essential oils tested have antifungal activity, with best results for C. zeylanicum. It is suggested to conduct other tests for evaluation of anti-Candida activity of this essential oil, which could represent possible therapeutic agent in the treatment of fungal infections of the oral cavity

Avaliação da atividade biológica de plantas medicinais brasileiras contra artemia salina leach / Assessment of biological activity of brazilian medicinal plants against artemia salina leach

Objetivo: avaliar a atividade biológica dos extratos de Pithecellobium cochliocarpum, Momordica charantia e Ipomoeaasarifolia isolados e associados através do bioensaio com Artemia salina. Método: prepararam-se soluções de diferentesconcentrações dos extratos e a elas foram adicionados metanáuplios de Artemia salina. Cada concentração foi testada emtriplicata, repetida em dois experimentos. Deixou-se o conjunto em incubação sob luz artificial por 24 h e após esseperíodo realizou-se a contagem do número de larvas vivas e mortas. Determinou-se a CL50 de acordo com o métodoestatístico de Probitos. Resultados: o valor da CL50 obtido para os extratos de Pithecellobium cochliocarpum, Momordicacharantia e Ipomoea asarifolia quando testados isoladamente foi de: 543,5 ppm, 400,9 ppm e 916,3 ppm,respectivamente. Para a associação de Pithecellobium cochliocarpum e Momordica charantia, Pithecellobiumcochliocarpum e Ipomoea asarifolia, e Momordica charantia e Ipomoea asarifolia, a CL50 encontrada foi, respectivamente:641,0 ppm, 502,2 ppm e 706,4 pppm. Já a associação dos três extratos apresentou uma CL50 de 990,8 ppm. Conclusão:Todos os extratos apresentaram atividade biológica frente Artemia salina. E suas associações podem levar à interaçõesentre seus constituintes. Estudos farmacológicos mais aprofundados devem ser realizados.

Atividade antifúngica in vitro do óleo essencial de Eucalyptus globulus L. sobre Candida spp. / Antifungal activity of the essential oils from Eucalyptus globulus L. on Candida spp

Considerando a necessidade de obtenção de novos agentes terapêuticos voltados para o combate da candidose bucal, o objetivo deste estudo foi investigar a atividade antifúngica in vitro do óleo essencial do Eucalyptus globulus L. (eucalipto) frente a espécies de Candida envolvidas com infecções bucais. Para tanto, ensaios microbiológicos com finalidade de determinar a Concentração Inibitória Mínima (CIM) e Concentração Fungicida Mínima (CFM) foram realizados, respectivamente, utilizando as técnicas da microdiluição e do crescimento de unidades formadores de colônias em meio sólido. Para o óleo essencial de E. globulus L. foram observadas CIM de 312,5 microg.mL-1 para 76,2% das cepas de Candida e CFM de 625 microg.mL-1 para 81% das cepas ensaiadas. Todas as cepas foram sensíveis aos antifúngicos sintéticos, miconazol e nistatina, utilizados como controles. Diante das condições estudadas e dos resultados obtidos, foi possível concluir que o óleo essencial de E. globulus L. apresentou atividade antifúngica sobre as espécies de Candida.

Considering the need to obtain new therapeutic agents aimed at acting against oral candidiasis, the objective of this study was to investigate the in vitro antifungal activity of the essential oil from Eucalyptus globulus L. (Eucalyptus) on Candida species involved in oral infections. Therefore, microbiological assays with the purpose of determining the Minimum Inhibitory Concentration (MIC) and Minimal Fungicidal Concentration (MFC) were performed, respectively, by using the technique of microdilution and the technique of colonies forming units growth on solid medium. For the essential oil from E. globulus L. were observed MIC of 312.5 microg.mL-1 for 76.2% of the Candida strains and MFC of 625 microg.mL-1 for 81% of the strains under study. All strains were sensitive to the synthetic antifungal agents, miconazole and nystatin, used as controls. From the conditions studied and from the results obtained, it's concluded that the essential oil from E. globulus L. showed antifungal activity on the Candida species.

Profile of susceptibility in vitro of Trichosporon asahii and Trichosporon inkin strains against cyclic imides

In vitro susceptibility testing of Trichosporon asahii (13 strains) and T. inkin (13 strains) against cyclic imides (succinimides, naphtalimides and maleimides) in concentrations of 200 to 6,25 μg/mL was performed according to the diffusion agar method. By the results obtained, the antifungal activity of the cyclic imides: 3,4-dichloro-N-phenyl-maleimide; 3,4-dichloro-N-phenyl-ethyl-maleimide and 3,4-dichloro-N-phenyl-propyl-maleimide (50 μg/mL) over T. asahii and T. inkin was important and it may be helpful in showing perspectives in a search for new antimicotic products.

O perfil de sensibilidade in vitro de Trichosporon asahii (13 cepas) e T. inkin (13 cepas) frente a imidas cíclicas (naftalimidas, succinimidas e maleimidas) nas concentrações de 6,25 a 200 μg/mL foi realizado pelo método de difusão em agar. Pelos resultados obtidos, a atividade antifúngica das imidas cíclicas: 3,4-dicloro-N-fenil-maleimida; 3,4-dicloro-N-fenil-etil-maleimida e 3,4-dicloro-N-fenil-propil-maleimida (50 μg/mL) sobre T. asahii e T. inkin foi importante e pode abrir perspectivas na busca de novos produtos antimicóticos.

Inhibitory effect of Cinnamomum zeylanicum Blume (Lauraceae) essential oil and beta-pinene on the growth of dematiaceous moulds

Dematiaceous moulds are pathogen microorganisms able to act as etiological agents of mycoses with different degrees of severity. This study evaluated the effectiveness of Cinnamomum zeylanicum Blume essential oil and beta-pinene in inhibiting the growth of various strains of dematiaceous moulds (Alternaria brassicola, Cladosporium herbarium, C. resinae, C. cladosporioides, Chaetomum globosum, Curvularia sp., Fonsecaea compacta, Piedraia hortae). Antimicrobial assays were led by determining the Minimum Inhibitory Concentration-MIC using the solid medium diffusion procedure and observing the interference of the MIC values on the mould radial mycelial growth along 14 days. MIC values found to C. zeylanicum essential oil oscillated between 63 and 125 µL/mL. beta-pinene showed MIC value of 125 µL/mL for the most mould strains, however C. resinae and C. globosum were resistant to it in all assayed concentrations. MIC values found to C. zeylanicum essential oil and beta-pinene presented intense fungicidal effect noted by a total inhibition of the mycelial growth of C. cladosporioides and F. compacta along 14 days of exposure. These results showed the intense antimould potential of C. zeylanicum essential oil and beta-pinene which could be regarded in a rational use in pharmaceutical formulations used to treat some mycoses, particularly, those caused by dematiaceous moulds.

Os fungos dematiáceos são microrganismos patogênicos capazes de agir como agentes etiológicos de micoses com diferentes graus de severidade. Este estudo avaliou a efetividade do óleo essencial de Cinnamomum zeylanicum Blume e beta-pineno em inibir o crescimento de várias cepas de fungos dematiáceos (Alternaria brassicola, Cladosporium herbarium, C. resinae, C. cladosporioides, Chaetomum globosum, Curvularia, Fonsecaea compacta, Piedraia hortae). Os ensaios antimicrobianos foram conduzidos através da determinação da Concentração Inibitória Mínima-CIM utilizando-se da técnica de difusão em meio sólido, bem como através da observação da interferência dos valores de CIM sobre o crescimento micelial radial fúngico ao longo de 14 dias. Os valores de CIM encontrados para o óleo essencial de C. zeylanicum oscilaram entre 63 e 125 µL/mL. beta-pineno apresentou um valor de CIM de 125 µL/mL para a maioria das cepas fúngicas, entretanto C. resinae e C. globosum mostraram-se resistentes a todas as concentrações ensaiadas. Os valores de CIM encontrados para C. zeylanicum e beta-pineno apresentaram intenso efeito fungicida notado por uma total inibição do crescimento micelial de C. cladosporioides e F. compacta ao longo de 14 dias de exposição. Estes resultados mostraram o intenso potencial antifúngico do óleo essencial de C. zeylanicum e beta-pineno, os quais poderiam ser considerados em um uso racional em formulações farmacêuticas utilizadas para a terapia de algumas micoses, particularmente, aquelas causadas por fungos dematiáceos.

Sensibilidade de fungos filamentosos isolados de alimentos, frente a extratos vegetais / Sensibility of fungi isolated of food, extracts vegetables

Uma considerável quantidade de ervas tem hoje seu potencial antimicrobiano bem estabelecido, surgindo como alternativas de emprego no controle da sobrevivência microbiana. Assim, este estudo teve como propósito avaliar o perfil de sensibilidade de cepas de fungos isoladas de alimentos frente extratos aquosos de algumas ervas de reconhecido potencial antimicrobiano, a citar Anarcodium accidentale (cajueiro), Cinamonum zeylanicum (canela), Bowdichia virgiloides (sucupira), Pithecellobium cocliocarpum (barbatimão) e Punica granatum (Romã). As cepas de Aspergillus niger, Fusarium spp., Penicillium spp. E Rhizopus spp. Não apresentaram sensibilidade a ação de nenhum dos sete extratos aquosos analisados, sendo que o A. flavus apresentou sensibilidade ao extrato de Bowdichia virgiloides e de Punica granatum, mostrando halos de inibição de 14m de diâmetro. Estes resultados evidenciam o alto poder de resistência destes microrganismos, confirmando seu destacado papel como agente de difícil controle, e conseqüentemente do potencial causador de deterioração de alimentos e de doenças veiculadas por alimentos.

Propriedades antibacterianas de óleos essenciais de plantas medicinais / Antibacterial properties of essential oils from medicinal plants

Objetivo: Realizar o estudo in vitro da atividade antibacteriana de óleos essenciais obtidos das seguintes plantas medicinais: Cinnamomum zeylanicum (canela), Citrus limonium (limoeiro), Cymbopogom citratus (Capim-santo), Eucaliptus globulus (eucalipto), Eugenia caryophillus (cravo da índia), E. uniflora (pitanga), Lippia alba (erva-cidreira), Matricaria chamomilla (camomila), Pneumus boldus (boldo), Ruta graveolens (arruda) e Zingiber officinalis (gengibre) sobre cepas de bactérias Gram negativas. Material e Métodos: Os óleos essenciais foram obtidos pela técnica de destilação por arraste com vapor de gua. Os ensaios das propriedades antibacterianas dos óleos essenciais, foram executados pela técnica de difusão em meio sólido. Resultados: Cinco dos nove óleos essenciais analisados apresentaram poder de inibição do crescimento de uma ou mais cepas de bactérias Gram negativas. Somente os óleos essenciais de R. graveolens e Z. officinalis não apresentaram ação inibitória sobre nenhuma cepa testada. Entretanto, o óleo essencial C. citratus obteve destaque entre os produtos analisados, o qual apresentou uma concentração inibitória mínima de 8 por cento para as cepas analisadas. Conclusão: Os óleos essenciais de plantas medicinais apresentam-se como agentes potencialmente efetivos na inibição do crescimento de bactérias Gram negativas, sendo destacada a ação do óleo essencial de C. citratus.

Estudo Toxicológico do Extrato Aquoso de Dioclea grandiflora Mart. Ex. Benth / Toxicological Studies of the Aqueous Extract of Dioclea grandiflora Mart. Ex. Benth

Objetivo: Determinar a toxicidade aguda e a Dose Letal 50 do extrato aquoso do caule de Dioclea grandiflora Mart. Ex. Benth. em camundongos albinos suícos. Material e métodos: O extrato aquoso do caule foi obtido por maceração, através de agitacão mecânica, por 24 horas e, posteriormente, tiofilizado. Para os estudos toxicológicos, vinte e quatro camundongos Mus musculus foram selecionados em seis grupos. Os animais permaneceram em jejum por dezoito horas antes de serem submetidos ao experimento. A via de administraçao utilizada foi a intraperitonal. Resultados: Os resultados sugerem que a atividade tóxica do extrato aquoso da casca do caule de Dioclea grandiflora, com Dose Letal 50 de 615mg/kg, foi baixa quando comparada com a casca de sua raiz. Conclusão: Diante do observado, conclui-se que existe uma relativa margem de segurança para o uso do extrato aquoso da casca do caule de Dioclea grandiflora como agente terapêutico