Detection of microorganisms with antibacterial activities from different industrial wastes and GC-MS analysis of crude microbial extract / Detecção de microrganismos com atividades antibacterianas de diferentes resíduos industriais e análise por GC-MS do extrato microbiano bruto

Many soil microorganisms' i.e., bacteria and fungi produce secondary metabolites called antibiotics. These are used for the treatment of some of the bacterial, fungal and protozoal diseases of humans. There is a need for isolation of a broad spectrum of antibiotics from microorganisms due to the emergence of antibiotic resistance. In the present study two antibiotic producing bacteria Klebsiella pneumoniae and Bacillus cereus were isolated from pharmaceutical and poultry feed industry of Hattar, Haripur Pakistan. Total 10 waste samples were collected from different industries (Marble, Ghee, Soap, Mineral, Steel, Poultry Feed, Pharmaceutical, Qarshi, Cosmetic and Glass). Thirty-three bacterial strains were isolated from industrial wastes of these ten different industries. Fourteen out of thirty-three bacterial strains exhibited antimicrobial activities against at least one of the test microbes considered in this study including Escherchia coli, Staphylococcus aureus and Salmonella typhi. The bacteria were isolated by standard serial dilution spread plate technique. Morphological characterization of the isolates was done by Gram staining. Nine bacterial isolates out of fourteen were initially identified as B. cereus and five as K. pneumoniae through biochemical characterization. The antibacterial activities were tested by well diffusion method. Maximum number of antibiotic producing bacteria were isolated from pharmaceutical and poultry feed industry based on the results of primary screening, the most potential isolates S9, S19, S20, S22 and S23 were selected for secondary screening. The maximum activity against E. coli and S. aureus was recorded by bacterial isolate S19 i.e zones of inhibition of 6.5mm and 9mm while S20 showed 7.5mm and 6mm zones respectively. Molecular identification was carried out on the basis of 16S rRNA sequence [...].

Muitos microrganismos do solo, ou seja, bactérias e fungos produzem metabólitos secundários chamados antibióticos. Eles são usados para tratamento de algumas doenças bacterianas, fúngicas e protozoárias em humanos. Há necessidade de isolamento de um amplo espectro de antibióticos de microrganismos devido ao surgimento de resistência aos antibióticos. No presente estudo, duas bactérias produtoras de antibióticos, Klebsiella pneumoniae e Bacillus cereus, foram isoladas da indústria farmacêutica e de ração avícola de Hattar, Haripur, Paquistão. Um total de 10 amostras de resíduos foi coletado de diferentes indústrias (mármore, ghee, sabão, mineral, aço, ração para aves, farmacêutica, Qarshi, cosmética e vidro). Trinta e três cepas bacterianas foram isoladas de resíduos industriais dessas dez diferentes indústrias. Quatorze das 33 cepas bacterianas exibiram atividades antimicrobianas contra pelo menos um dos micróbios de teste considerados neste estudo, incluindo Escherchia coli, Staphylococcus aureus e Salmonella typhi. As bactérias foram isoladas pela técnica de placa de diluição em série padrão. A caracterização morfológica dos isolados foi feita por coloração de gram. Nove isolados bacterianos de 14 foram inicialmente identificados como B. cereus e cinco como K. pneumoniae por meio de caracterização bioquímica. As atividades antibacterianas foram testadas pelo método de difusão em poço. O número máximo de bactérias produtoras de antibióticos foi isolado da indústria farmacêutica e de ração avícola com base nos resultados da triagem primária, os isolados mais potenciais S9, S19, S20, S22 e S23 foram selecionados para a triagem secundária. A atividade máxima contra E. coli e S. aureus foi registrada pelo isolado bacteriano S19, ou seja, zonas de inibição de 6,5 mm e 9 mm, enquanto S20 mostrou zonas de 7,5 mm e 6 mm, respectivamente. A identificação molecular foi realizada com base na análise da sequência 16S [...].

Os proprietários de cães podem compartilhar do mesmo perfil de resistência que seus cães? / Can dog owners share the same resistance profile that their dogs? / ¿pueden los propietarios de perros compartir el mismo perfil de resistencia que sus perros?

Atualmente, o uso indiscriminado de antimicrobianos tem contribuído para o aparecimento de microrganismos resistentes, pois, os mesmos ao entrarem em contato com o princípio ativo dessas drogas de forma indevida, desenvolvem características fisiológicas e genéticas tais como a mutação de seu DNA, podendo passar esses genes de resistência à sua descendência por meio de replicação ou por conjugação de plasmídeos, fazendo com que se reduzam as opções de tratamentos efetivos para as infecções bacterianas, aumentando assim as complicações clínicas de pacientes, sejam eles o homem ou os animais de companhia e/ou produção. Recentemente o nosso grupo de pesquisa realizou um estudo com proprietários de cães do curso de Medicina Veterinária e resultados prévios demonstraram alto perfil de resistência aos antimicrobianos da classe das penicilinas, sendo a amoxicilina o antimicrobiano que apresentou menor eficácia, dentre os antimicrobianos testados para aquela classe. Um dos principais fatores relacionados ao aparecimento de resistência está relacionado ao seu uso excessivo e segundo avaliação prévia dos questionários dos tutores verificou-se um predomínio do uso desse antimicrobiano, tanto pelos tutores quanto para tratamento dos animais. Além disso, a falta de informação dos pacientes e o comportamento dos mesmos em relação aos seus animais de companhia levam-os a utilizarem doses insuficientes dos antimicrobianos quando os mesmos suspendem seu uso quando o animal apresenta melhora clínica. Cabe salientar ainda, a existência de resistência intrínseca do micro-organismo à antimicrobianos específicos, demonstrando a necessidade do isolamento e identificação do micro-organismo e realização da antibiograma para escolha mais adequada do antimicrobiano a ser prescrito. Conclui-se que os proprietários de cães podem compartilhar do mesmo perfil de resistência aos antimicrobianos que seus cães, demonstrando a necessidade da orientação dos mesmos para se reduzir o índice de resistência aos antimicrobianos.(AU)

The indiscriminate use of antimicrobials in recent times has contributed to the emergence of resistant microorganisms by improperly coming into contact with the active principle of such drugs and developing physiological and genetic characteristics such as DNA mutation. These resistant genes can be passed along to their offspring by replication or plasmid conjugation, reducing the options of effective treatments for bacterial infections, thus increasing the clinical complications of patients, whether humans or pets and/or livestock. Recently, the authors held a study with dog owners from the Veterinary Medicine course and the initial results showed a high profile of resistance to antimicrobials belonging to the penicillin class, with amoxicillin being the least effective antimicrobial among the ones tested for the class. One of the main factors related to the appearance of resistance is related to its excessive use, and according to previous assessment of the tutors' questionnaires, there was a predominance of the use of this antimicrobial both by the tutors and for the treatment of their animals. In addition, the patients' lack of information and their behavior regarding their pets lead them to use insufficient doses of antimicrobials, since they discontinued its use when the animal presented signs of clinical improvement. It is also important to note the existence of microorganism intrinsic resistance to specific antimicrobials, demonstrating the necessity of isolation and identification of the microorganism, as well as carrying out an antibiogram for the most appropriate choice of antimicrobial to be prescribed. It can be concluded that dog owners can share the same antimicrobial resistance profile as their dogs, demonstrating the need for guidance in order to reduce the antimicrobial resistance index.(AU)

Actualmente, el uso indiscriminado de antimicrobianos ha contribuido a la aparición de microorganismos resistentes, ya que entran en contacto de manera inadecuada con el principio activo de estos fármacos, desarrollan características fisiológicas y genéticas como la mutación de su ADN, pudiendo transmitir esos genes de resistencia a su descendencia por replicación o conjugación de plásmidos, haciendo con que reduzcan las opciones de tratamientos efectivos para las infecciones bacterianas, aumentando así las complicaciones clínicas de los pacientes, sean humanos o mascotas y/o producción. Recientemente, nuestro grupo de investigación realizó un estudio con dueños de perros del curso de Medicina Veterinaria y los resultados anteriores mostraron un alto perfil de resistencia a los antimicrobianos de la clase de las penicilinas, siendo la amoxicilina el antimicrobiano menos efectivo entre los antimicrobianos probados para esa clase. Uno de los principales factores relacionados con la aparición de resistencia está relacionado a su uso excesivo y, según la evaluación previa de los cuestionarios de los tutores se verificó un predominio del uso de ese antimicrobiano, tanto por parte de los tutores como para el tratamiento de los animales. Además, la falta de información de los pacientes y el comportamiento de los mismos con respecto a sus mascotas los llevan a usar dosis insuficientes de antimicrobianos cuando el animal muestra una mejoría clínica. Todavía cabe mencionar la existencia de resistencia intrínseca del microorganismo a antimicrobianos específicos, lo que demuestra la necesidad de aislamiento e identificación del microorganismo y la realización de antibiograma para la elección más adecuada de antimicrobianos a recetar. Se puede concluir que los dueños de perros pueden compartir del mismo perfil de resistencia a los antimicrobianos que sus perros, lo que demuestra la necesidad de su orientación para reducir el índice de resistencia a los antimicrobianos.(AU)

Effect of γ-lactones and γ-lactams compounds on Streptococcus mutans biofilms

Abstract Considering oral diseases, antibiofilm compounds can decrease the accumulation of pathogenic species such as Streptococcus mutans at micro-areas of teeth, dental restorations or implant-supported prostheses. Objective To assess the effect of thirteen different novel lactam-based compounds on the inhibition of S. mutans biofilm formation. Material and methods We synthesized compounds based on γ-lactones analogues from rubrolides by a mucochloric acid process and converted them into their corresponding γ-hydroxy-γ-lactams by a reaction with isobutylamine and propylamine. Compounds concentrations ranging from 0.17 up to 87.5 μg mL-1 were tested against S. mutans. We diluted the exponential cultures in TSB and incubated them (37°C) in the presence of different γ-lactones or γ-lactams dilutions. Afterwards, we measured the planktonic growth by optical density at 630 nm and therefore assessed the biofilm density by the crystal violet staining method. Results Twelve compounds were active against biofilm formation, showing no effect on bacterial viability. Only one compound was inactive against both planktonic and biofilm growth. The highest biofilm inhibition (inhibition rate above 60%) was obtained for two compounds while three other compounds revealed an inhibition rate above 40%. Conclusions Twelve of the thirteen compounds revealed effective inhibition of S. mutans biofilm formation, with eight of them showing a specific antibiofilm effect.

Synthesis of some novel enzyme inhibitors and antibacterial agents derived from 5-(1-(4-tosyl)piperidin-4-yl)-1, 3, 4-oxadiazol-2-thiol

ABSTRACT Keeping in mind the pharmacological importance of the 1,3,4-oxadiazole moiety, a series of new S-substituted derivatives, 5a-h, of 5-(1-(4-tosyl)piperidin-4-yl)-1,3,4-oxadiazol-2-thiol (3) were synthesized. The reaction of p-toluenesulfonyl chloride (a) and ethyl isonipecotate (b) produced ethyl 1-(4-tosyl)piperidin-4-carboxylate (1) which was further transformed into 1-(4-tosyl)piperidin-4-carbohydrazide (2) by hydrazine hydrate in methanol. Compound 2 was refluxed with CS2 in the presence of KOH to synthesize 5-(1-(4-tosyl)piperidin-4-yl)-1,3,4-oxadiazol-2-thiol (3). The desired compounds, 5a-h, were synthesized by stirring 3 with aralkyl halides, 4a-h, in DMF using NaH as an activator. The structures of synthesized compounds were elucidated by 1H-NMR, IR and EI-MS spectral studies. These compounds were further evaluated for enzyme inhibitory activity against lipoxygenase and alpha-glucosidase, along with antibacterial activity against Gram-negative and Gram-positive bacteria.

RESUMO Tendo em vista a importância farmacológica da porção 1,3,4-oxadiazol, sintetizou-se uma série de novos derivados S-substituídos, 5a-h, de 5-(1-(4-tosi)piperidin-4-il)-1,3,4-oxadiazol-2-tiol (3). A reação do cloreto de p-toluenossulfonila (a), com isonipecotato de (b) etila forneceu 1-(4-tosil)piperidin-4-carboxilato de metila (1), que foi, em seguida, transformado em 1-(4-tosil)piperidin-4-carbo-hidrazida (2) por reação com hidrato de hidrazina em metanol. O composto 2 foi submetido a refluxo com CS2 na presença de KOH para se obter 5-(1-(4-tosil)piperidin-4-il)-1,3,4-oxadiazol-2-tiol (3). Os compostos desejados, 5a-h, foram obtidos por agitação de 3 com haletos de aralquila, 4a-h, em DMF, na presença de NaH. As estruturas dos compostos sintetizados foram elucidadas através de análise dos espectros de 1H-MNR, IR e EI-MS. Estes compostos foram, ainda, avaliados quanto à inibição das enzimas lipoxigenase e alfa-glucosidase, juntamente com a atividade antibacteriana contra bactérias Gram positivas e Gram negativas.

Introduction of soft drinks and processed juice in the diet of infants attending public day care centers / Introdução de refrigerantes e sucos industrializados na dieta de lactentes que frequentam creches públicas

OBJECTIVE: Identifying at what age infants enrolled in public day care centers are introduced to soft drinks and industrialized juice, as well as comparing the nutritional composition of these goods with natural fruit juice. METHODS: A cross-sectional study with the mothers of 636 children (aged 0 to 36 months) from nurseries of day care centers, who were asked questions about the age of feeding introduction. This study evaluated the proximate composition of soft drinks and artificial juice, comparing them with those of natural fruit juice regarding energy, sugar, fiber, vitamin C, and sodium values. The chemical composition of fruit juice was obtained by consulting the Table of Food Composition and, for industrialized drinks, the average nutritional information on the labels of the five most consumed product brands. RESULTS: The artificial drinks were consumed before the first year of life by more than half of the children studied, however, approximately 10% consumed them before the age of 6 months. With regard to the comparison among the drinks, artificial fruit juice beverages and soft drinks proved to contain from nine to 13 times higher amounts of sodium, and 15 times less vitamin C than natural juices. CONCLUSIONS: The introduction of soft drinks and industrialized juice in the diet of infants was inopportune and premature.. When compared to natural fruit juice, these have inferior nutritional composition, which suggests the urgent need for measures based on strategies for food and nutrition education in order to promote awareness and the maintenance of healthy eating habits. .

OBJETIVO: Identificar a idade de introdução do refrigerante e de sucos industrializados na dieta de lactentes matriculados em berçários de creches públicas e comparar as composições nutricionais dessas bebidas com as do suco de fruta natural. MÉTODOS: Estudo transversal com 636 crianças (de zero a 36 meses) de berçários de creches, cujas mães foram entrevistadas sobre idade de introdução dos alimentos. Avaliaram-se as composições centesimais do refrigerante e sucos industrializados, comparando-as com as do suco de laranja natural para valor energético, açúcar, fibra, vitamina C e sódio. A composição centesimal do suco de laranja foi obtida por meio de consulta à Tabela de Composição de Alimentos e, para as bebidas industrializadas, utilizaram-se as médias das informações nutricionais contidas nos rótulos de cinco marcas mais consumidas dos produtos. RESULTADOS: O refrigerante e suco industrializado foram consumidos antes do primeiro ano de vida por mais da metade das crianças estudadas, sendo que cerca de 10% o consumiram antes dos seis meses. Quando comparadas à composição do suco de laranja natural, bebidas forneceram quantidades de 9 a 13 vezes superiores de sódio e 15 vezes inferiores de vitamina C. CONCLUSÕES: A introdução de refrigerantes e sucos industrializados na dieta dos lactentes foi inoportuna e precoce. Comparados ao suco de fruta natural, tais bebidas possuem composição nutricional inferior, sugerindo a necessidade de medidas fundamentadas em estratégias de educação alimentar e nutricional como forma de promover a formação e manutenção de hábitos alimentares saudáveis. .

Factors impacting the growth and nutritional status of cystic fibrosis patients younger than 10 years of age who did not undergo neonatal screening / Fatores que afetam o crescimento e estado nutricional de pacientes com fibrose cística com idade inferior a 10 anos e que não foram submetidos à triagem neonatal

OBJECTIVE: The aim of this study was to evaluate by clinical and laboratory parameters how cystic fibrosis (CF) affects growth and nutritional status of children who were undergoing CF treatment but did not receive newborn screening. METHODS: A historical cohort study of 52 CF patients younger than 10 years of age were followed in a reference center in Campinas, Southeast Brazil. Anthropometric measurements were abstracted from medical records until March/2010, when neonatal screening program was implemented. Between September/2009 and March/2010, parental height of the 52 CF patients were also measured. RESULTS: Regarding nutritional status, four patients had Z-scores ≤-2 for height/age (H/A) and body mass index/age (BMI/A). The following variables were associated with improved H/A ratio: fewer hospitalizations, longer time from first appointment to diagnosis, longer time from birth to diagnosis and later onset of respiratory disease. Forced vital capacity [FVC(%)], forced expiratory flow between 25-75% of FVC [FEF25-75(%)], forced expiratory volume in the first second [FEV1(%)], gestational age, birth weight and early respiratory symptoms were associated with improved BMI/A. CONCLUSIONS: Greater number of hospitalizations, diagnosis delay and early onset of respiratory disease had a negative impact on growth. Lower spirometric values, lower gestational age, lower birth weight, and early onset of respiratory symptoms had negative impact on nutritional status. Malnutrition was observed in 7.7% of cases, but 23% of children had nutritional risk. .

OBJETIVO: Avaliar por meio de parâmetros clínicos e laboratoriais como a fibrose cística (FC) afeta o crescimento e estado nutricional de crianças submetidas ao tratamento de FC que não foram submetidas à triagem neonatal. MÉTODOS: Uma coorte histórica com 52 pacientes com FC menores de 10 anos foi acompanhada em um centro de referência em Campinas, Sudeste do Brasil. Peso e altura foram coletados de prontuários médicos até março de 2010, quando a triagem neonatal foi implementada. Entre setembro de 2009 a março de 2010 a altura dos pais foi medida. RESULTADOS: Quatro pacientes tiveram escores Z ≤ -2 para altura/idade (A/I) e índice de massa corporal/idade (IMC/A). As seguintes variáveis foram associadas com melhor razão A/I: menor número de hospitalizações, maior tempo entre a primeira consulta e o diagnóstico, maior tempo entre o nascimento e o diagnóstico e início tardio da doença respiratória. Capacidade vital forçada [CVF(%)], fluxo expiratório forçado entre 25-75% da CVF [FEF25-75(%)], volume expiratório forçado no primeiro segundo [VEF1(%)], idade gestacional, peso ao nascer e início dos sintomas respiratórios foram associados com melhor IMC/I. CONCLUSÕES: Maior número de hospitalizações, retardo no diagnóstico e início precoce da doença respiratória tiveram impacto negativo no crescimento. Menores valores espirométricos, menor idade gestacional, menor peso ao nascer e o início precoce dos sintomas respiratórios tiveram impacto negativo no estado nutricional. A desnutrição foi observada em 7,7% dos casos, mas 23% das crianças apresentaram risco nutricional. .

Homologous human milk supplement for very low birth weight preterm infant feeding / Aditivo homólogo para a alimentação do recém-nascido pré-termo de muito baixo peso

OBJECTIVE: To develop a homologous human milk supplement for very low-birth weight infant feeding, using an original and simplified methodology, to know the nutritional composition of human milk fortified with this supplement and to evaluate its suitability for feeding these infants. METHODS: For the production and analysis of human milk with the homologous additive, 25 human milk samples of 45mL underwent a lactose removal process, lyophilization and then were diluted in 50mL of human milk. Measurements of lactose, proteins, lipids, energy, sodium, potassium, calcium, phosphorus and osmolality were performed. RESULTS: The composition of the supplemented milk was: lactose 9.22±1.00g/dL; proteins 2.20±0.36g/dL; lipids 2.91±0.57g/dL; calories 71.93±8.69kcal/dL; osmolality 389.6±32.4mOsmol/kgH2O; sodium 2.04±0.45mEq/dL; potassium 1.42±0.15mEq/dL; calcium 43.44±2.98mg/dL; and phosphorus 23.69±1.24mg/dL. CONCLUSIONS: According to the nutritional contents analyzed, except for calcium and phosphorus, human milk with the proposed supplement can meet the nutritional needs of the very low-birth weight preterm infant. .

OBJETIVO: Elaborar com metodologia original e simplificada um aditivo homólogo do leite humano para a alimentação do recém-nascido de muito baixo peso, conhecer a composição nutricional do leite humano fortificado com esse aditivo e avaliar sua adequação para a alimentação desses recém-nascidos. MÉTODOS: Para a produção e análise do leite humano com o aditivo homólogo, 25 amostras de 45 mL de leite humano passaram por processos de retirada de lactose, liofilização e foram diluídas em 50 mL de leite humano. Foram feitas dosagens de lactose, proteínas, lipídios, energia, sódio, potássio, cálcio, fósforo e osmolalidade. RESULTADOS: A composição do leite aditivado foi lactose 9,22 ± 1 g/dL; proteínas 2,20 ± 0,36 g/dL; lípides 2,91 ± 0,57 g/dL; calorias 71,93 ± 8,69 kcal/dL; osmolalidade 389,6 ± 32,4mOsmol/kgH2O; sódio 2,04 ± 0,45mEq/dL; potássio 1,42 ± 0,15mEq/dL; cálcio 43,44 ± 2,98 mg/dL; e fósforo 23,69 ± 1,24 mg/dL. CONCLUSÕES: De acordo com os teores nutricionais analisados, com exceção do cálcio e do fósforo, o leite humano com o aditivo proposto pode atender às necessidades nutricionais do recém-nascido pré-termo de muito baixo peso. .

Synthesis, DNA cleavage and antimicrobial activity of 4-thiazolidinones-benzothiazole conjugates.

Antimicrobial screening of several novel 4-thiazolidinones with benzothiazole moiety has been performed. These compounds were evaluated for antimicrobial activity against a panel of bacterial and fungal strains. The strains were treated with these benzothiazole derivatives at varying concentrations, and MIC’s were calculated. Structures of these compounds have been determined by spectroscopic studies viz., FT-IR, 1H NMR, 13C NMR and elemental analysis. Significant antimicrobial activity was observed for some members of the series, and compounds viz. 3-(4-(benzo[d]thiazol-2-yl) phenyl)-2-(4-methoxyphenyl)thiazolidin-4-one and 3-(4-(benzo[d]thiazol-2-yl)phenyl)-2-(4-hydroxy phenyl)thiazolidin-4-one were found to be the most active against E.coli and C.albicans with MIC values in the range of 15.6–125 μg/ml. Preliminary study of the structure–activity relationship revealed that electron donating groups associated with thiazolidine bearing benzothiazole rings had a great effect on the antimicrobial activity of these compounds and contributes positively for the action. DNA cleavage experiments gave valuable hints with supporting evidence for describing the mechanism of action and hence showed a good correlation between their calculated MIC’s and its lethality.

In vitro antibacterial activity of tigecycIine against clinical isolates of linezolid-Intermediate and linezolid-resistant enterococci by time-kill assay

Introduction: Enterococci have become the third leading cause of nosocomial bacteraemia, an infection which is significantly associated with the risk of developing infective endocarditis. Linezolid provides high rates of clinical cure and microbiologic success in complicated infections due to Enterococcus spp. However, several instances of emergence of resistance during linezolid treatment have been reported. The aim of this study was evaluate the activity of tigecycline against linezolidintermediate (LIE) and linezolid-resistant enterococcus faecalis(LRE) by the timekill assay. Methods: Five isolates of LRE and two isolates of LIE were used in this study. Minimum inhibitory concentration (MIC) was determined by broth dilution following the guidelines from the Clinical and Laboratory Standards Institute (CLSI). Time-kill assay was employed to access the in vitro response profile of tigecycline. Results: All seven isolates presented MIC of 0.125 ìg/mL. Tigecycline activity was individually evaluated according to CLSI criteria. This antibiotic showed bactericidal activity against three of the five isolates of LRE and bacteriostatic activity against the other isolates. Conclusions: Tigecycline presented both bacteriostatic and bactericidal activity against tested isolates, which is an important data that must be considered for new studies.

Newly-synthesized chalcones-inhibition of adherence and biofilm formation of methicillin-resistant Staphylococcus aureus

Biofilm formation and adherence of bacteria to host tissue are one of the most important virulence factors of methicillin-resistant strains of Staphylococcus aureus (MRSA). The number of resistant strains is seriously increasing during the past years and bacteria have become resistant, not only to methicillin, but also to other commonly used antistaphylococcal antibiotics. There is a great need for discovering a novel antimicrobial agent for the treatment of staphylococcal infections. One of the most promising groups of compounds appears to be chalcones. In present study we evaluated the in vitro effect of three newly synthesized chalcones: 1,3-Bis-(2-hydroxy-phenyl)-propenone, 3-(3Hydroxy-phenyl)-1-(2-hydroxy-phenyl)-propenone and 3-(4-Hydroxy-phenyl)-1-(2-hydroxyphenyl)-propenone on glycocalyx production, biofilm formation and adherence to human fibronectin of clinical isolates and laboratory control strain of MRSA (ATCC 43300). Subinhibitory concentrations of the tested compounds reduced the production of glycocalyx, biofilm formation and adherence to human fibronectin of all MRSA strains. Inhibition of biofilm formation was dose dependent and the most effective was 1,3-Bis-(2-hydroxy-phenyl)-propenone. In our study we demonstrated that three newly-synthesized chalcones exhibited significant effect on adherence and biofilm formation of MRSA strains. Chalcones may be considered as promising new antimicrobial agents that can be used for prevention of staphylococcal infections or as adjunct to antibiotics in conventional therapy.

Synthesis, anti-bronchoconstrictive, and antibacterial activities of some new 8-substituted-1,3-dimethylxanthine derivatives

Methylxanthines especially theophylline have been recognized as potent bronchodilators for the relief of acute asthma for over 50 years. Recently, it was found that bacterial infection has a role in asthma pathogenesis. Accordingly, the present work involves the synthesis of different series of 8-substituted [aryl, aralkyl, cycloalkyl, and heteroaryl]-l,3-dimethylxanthines. The chemical structures of these compounds were elucidated by IR, [1]H NMR, [13]C NMR, elemental analyses, and high resolution EI-MS or FAB-MS for some compounds. The bronchodilator activity was evaluated using acetylcholine induced bronchospasm in guinea pigs, and most of the compounds showed significant anti-bronchoconstrictive activity in comparison with aminophylline as a standard. Also, the antibacterial activity of all the target compounds was investigated in-vitro against Gram-positive and Gram-negative bacteria using ampicillin as a reference drug. Results showed that some of the tested compounds have potent antibacterial activity. A pharmacophore model was computed to get useful insight on the essential structural features of bronchodilator activity

Drogas antimicrobianas / Antimicrobial Drugs

A palavra antibiótico, originária do termo antibiose, define a(s) substância(s) elaborada(s) por seres vivos, capazes de agir como tóxicos seletivos em pequenas concentrações, sobre os microorganismos. O mecanismo de ação dos antibióticos é exercido essencialmente por: interferência na síntese da parede celular, inibição da síntese de proteínas; injúria à membrana citoplasmática; inibição da síntese de ácidos nucléicos e da síntese de metabólitos essenciais. O maior interesse premente é com o uso inadequado dos antibióticos, o que aumenta a probabilidade da emergência de cepas bacterianas resistentes. Lamentavelmente, a problemática da resistência a drogas antimicrobianas tem alcançado um ponto crítico. Para superar essa crise, serão necessárias novas condutas, tais como intensivas campanhas educacionais e pesquisas científicas que enfoquem o desenvolvimento de antibióticos alternativos, produzidos por plantas e animais

Antibiotic resistance--a close look.

The discovery of antibiotic greatly improved the human health care system. But today we are facing the problem of antibiotic resistance due to uncontrolled use of the compound. This can be by passed by controlled use of antibiotic and formulation of newer ones.

Estreptomicina: propiedades fisicoquímicas y toxicidad vestibular / Streptomycin, physical and chemical characteristics and vestibular toxicity

Propósito: Los antibióticos aminoglucósidos estreptomicina (STP) y kanamicina (KAN) son tóxicos para las células sensoriales del vestíbulo y de la cóclea, respectivamente. Químicamente están constituidos por estreptidina (STD) un derivado del inositol y dos azúcares, la esteptosa (Stosa) y la N-metilglucosamida (nm-GLUN); sin embargo, en la STP, la STD tiene dos sustituyentes guanidino, los que están ausentes en la KAN. Por lo tanto, se propone estudiar si la vestíbulo-toxicidad específica de la STP se debe a los grupos guanidino. Material y Métodos: Se incubaron en vitro, membranas celulares aisladas de los órganos vestibulares, con 3H-espermidina (3H-Spdina), un análogo estructural de la STP. Se midió la capacidad de los siguientes compuestos: STP, STD, KAN, guanidina (GUA) y n-acetilglucosamina (na-GLUN) para desplazarlos específicamente. Resultados: Se encontró que el orden de desplazamiento de la 3HSPdina para esas sustancia era STP=STD KanGUAn-a-GLUN. Conclusiones: Los resultados sugieren fuertemente que la STP debe su especificidad vestibulotóxica, a la presencia de los grupos guanidino en la porción de STD de su molécula, los que interactuarían por sus cargas positivas con estructuras membranales vestibulares relacionadas con la transducción, muy probablemente los cilios sensorios de las células ciliadas vestibulares

Synthesis and antibacterial activity of some Schiff bases and 4-thiazolidinones.

Some new schiff bases (1a-d) 4-thiazolidinones (2a-d) have been synthesised and tested for their antibacterial activity. The structures of these compounds have been established on the basis of elemental analysis and spectral data (IR and H1 NMR).

Synthesis of 2-alkoxy-3cyano-4,6-diarylpyridines as antibacterial agents

Two facile synthetic methods were adopted for the preparation of new series of 2-alkoxy-3-cyano-4, 6-diarylpyridines VI-Xa-e. The first involved the reaction of substituted chalcones with malononitrile in sodium alkoxide-alcohol system. The second reacted the arylidene malononitrile XI, XII with the appropriate aryl methyl ketones XIII-XV in sodium alkoxide-alcohol system. The two methods gave good yields of the target compounds VI-Xa-e. Representative examples of the newly synthesized compounds were evaluated for antibacterial activity

Síntese e atividade antiestafilocócica do derivado 2-acetóxi-1, 4-naftoquinona / Synthesis and anti-staphylococcus activity of 2-acetoxi-1, 4-naftoquinona derivative

O derivado 2-acetóxi-1, 4-naftoquinona (DNQ), sintetizado por Ferreira, foi testado contra seis diferentes espécies de bactérias isoladas de pacientes do Hospital Universitário Antônio Pedro (HUAP). A droga exibiu atividade apenas contra cepas Gram-positivas (zonas de inibição = 12 mm, em testes preliminares): Enterococcus faecalis, Staphylococcus aureus e Staphylococcus epidermidis. Para os isolados de S. aureus, as concentrações mínimas inibitórias (CMIs) e mínimas bactericidas (CMBs) variaram de 16mug a 256 mug/ml e de 64 mug a 512 mug/ml, respectivamente. Através da espectrofotometria de absorção em 560nm, DNQ originou cinéticas de inibição diretamente proporcionais às suas concentrações, com 2CMI promovendo resposta lítica (apenas na 1ª hora de tratamento) nas cepas sensíveis à oxacilina. Em nível de viabilidade celular (UFC/ml), os efeitos do derivado também cresceram na razão direta do aumento de sua concentração, com 2 x CMI acarretando uma resposta bactericida bem nítida (já na 2ª hora de ação), contra as cepas sensíveis ao Beta-lactâmico. Apesar da menor atividade do DNQ em relação aos antibióticos de uso em clínica, estamos continuando os estudos com o derivado, agora, na tentativa de, através da modificação de sua estrutura, ampliar o seu espectro de ação e a sua atividade antibacteriana.

Synthesis of some new quinoline derivatives of potential antimicrobial activity

A series of quinolinoxy methyl-1,3,4-oxadiazoles [2 and 3], N-imido derivatives [5,6], pyrazole [7], pyrazolone [8], pyrazolidindione [9], Schiff bases [10a-f] and 8-O [2-oxo-3-indolinylidene] acetic acid hydrazido] 5,7 diiodoquinoline [4] was prepared. Some of the new compounds showed considerable antimicrobial activity against Gram +ve and Gram -ve bacteria, yeast and fungi

Studies on some phenolic and flavonoid contents of vicia faba hulls and their antibacterial activity

Vicia faba hulls [broad bean Giza 2, Leguminosae] appeared to contain 18 flavonoid glycosides, three aglycones and two phenolic acids. They were isolated from the 80% aqueous ethanolic extract after its fractional extraction using diethyl ether and ethyl acetate. The structure of the isolated compounds was identified through chromatographic, chemical and spectral analyses. The antibacterial effect of these extracts and some of the isolated compounds was studied by using the agar-diffusion technique on six different microorganisms [bacteria]

Mutagénesis con luz ultravioleta (UV) de una cepa del género streptomyces productora de antibiótico / Ultraviolet mutagenesis of an antibiotic-producing straing of the genre streptomyces

Se aíslan 6 mutantes auxotróficos por la técnica de plaqueo por réplica después de la mutagénesis con luz ultravioleta (UV). Se señala que en la caracterización todos resultaron alterados en la vía de síntesis de la arginina. Se aíslan 4 revertantes espontáneos de 3 de los mutantes. Se informa que la aplicación del método de Kelner de difusión en agar para determinar la producción antibiótica a mutantes y revertantes y el procesamiento estadístico de los resultados obtenidos, evidenció que no existen diferencias significativas entre la cepa parental y los mutantes, pero sí entre la cepa parental y los revertantes, y produce uno de ellos, el 28-2, significativamente menos que la cepa RA-2. Se indica que el cálculo del coeficiente de variación para los mutantes evidenció una mayor estabilidad de los mutantes 20, 25, 26, y 28 en relación con la cepa parental, y el 25 es 5 veces más estable que éste