Antimicrobial activity Research Papers - Academia.edu (original) (raw)

Hydro-distillation of the air dried and pulverized whole plant of Euphorbia graminea yielded colourless volatile oil which was analysed by gas chromatography-mass spectrometry. Isopropyl palmitate (45.81%), Oleic acid (14.09%), Palmitic... more

Hydro-distillation of the air dried and pulverized whole plant of Euphorbia graminea yielded colourless volatile oil which was analysed by gas chromatography-mass spectrometry. Isopropyl palmitate (45.81%), Oleic acid (14.09%), Palmitic acid (6.65%) and Trans-2-Pentenal (5.68%) were the major constituents in the oil. The volatile oil revealed good antimicrobial activity against ten tested strains of clinical isolates of bacteria and fungi. It was observed that the potency of the volatile oil increased with increase in concentration. High zones of inhibition were observed across all the microorganisms tested at 100µg/ml. Antioxidant activity of the volatile oil tested using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical assay revealed a moderate activity (40%) at concentration of 1000 µg/ml. The present study confirms the traditional use of E. graminea in folk medicine for dermatological diseases and microbial infections.

Background Suppression of immune system in treated cancer patients may lead to secondary infections that obviate the need of antibiotics. In the present study, an attempt was made to understand the occurrence of secondary infections in... more

Background Suppression of immune system in treated cancer patients may lead to secondary infections that obviate the need of antibiotics. In the present study, an attempt was made to understand the occurrence of secondary infections in immuno-suppressed patients along with herbal control of these infections with the following objectives to: (a) isolate the microbial species from the treated oral cancer patients along with the estimation of absolute neutrophile counts of patients (b) assess the in vitro antimicrobial activity medicinal plants against the above clinical isolates. Methods Blood and oral swab cultures were taken from 40 oral cancer patients undergoing treatment in the radiotherapy unit of Regional Cancer Institute, Pt. B.D.S. Health University, Rohtak, Haryana. Clinical isolates were identified by following general microbiological, staining and biochemical methods. The absolute neutrophile counts were done by following the standard methods. The medicinal plants selected...

The aim of this work was to isolate a lectin from Myracrodruon urundeuva heartwood and to evaluate its antimicrobial activity against bacteria and fungi that attack plants, including woods. The lectin was isolated from heartwood through... more

The aim of this work was to isolate a lectin from Myracrodruon urundeuva heartwood and to evaluate its antimicrobial activity against bacteria and fungi that attack plants, including woods. The lectin was isolated from heartwood through affinity chromatography on a chitin column monitored by hemagglutination assay. The lectin inhibited Gram-negative and Gram-positive bacteria and was more effective than antifungal Cercobin in growth inhibition of phytopathogenic fungi. The detected antimicrobial activity reveals the possible role of the lectin in the resistance of M. urundeuva heartwood against deteriorative biological agents. The M. urundeuva lectin is the first bioactive peptide found in heartwood, probably stored as a chemical protection against biodegradation.

This study was carried out to investigate the antifungal and immunomodulatory activities of Bryophylum pinnatum. Both aqueous and ethanol solvents were used for extraction. Five fungal species including Aspergillus niger, Aspergillus... more

This study was carried out to investigate the antifungal and immunomodulatory activities of Bryophylum pinnatum. Both aqueous and ethanol solvents were used for extraction. Five fungal species including Aspergillus niger, Aspergillus flavus, Cladosporium herbarium, Candida albicans and Penicillium italicum were obtained from the University of Benin Teaching Hospital and they were preliminarily identified using standard microbiological methods. Wistar rat models for the study were purchased and acclimatized for a period of two weeks. The rats were divided into five groups and orally administered with the ethanol extract of the plant while one group served as control. Antimicrobial and hematological parameters including packed cell volume (PCV), hemoglobin, white blood cell counts, platelets and CD4 count were assayed using standard methods. The only fungus sensitive to aqueous extract was Aspergillus niger, with zone of inhibition ranging from 6.00±0.58-11.33±0.33 mm at concentration...

An eco-friendly microbial method for synthesis of silver colloid solution with antimicrobial activity is developed using a fungal strain of Peni-cillium purpurogenum NPMF. It is observed that increase in concentration of AgNO3 increases... more

An eco-friendly microbial method for synthesis of silver colloid solution with antimicrobial activity is developed using a fungal strain of Peni-cillium purpurogenum NPMF. It is observed that increase in concentration of AgNO3 increases the formation of silver nanoparticle. At ...

Since the 1950s, antibiotics have been the “silver bullet” for the treatment of diseases in both the medical and livestock industries. The use of subtherapeutic antibiotics in broilers not only prevents disease outbreaks but also... more

Since the 1950s, antibiotics have been the “silver bullet” for the treatment of diseases in both the medical and livestock industries. The use of subtherapeutic antibiotics in broilers not only prevents disease outbreaks but also increases meat yield and feed conversion.1 The mode of action for the added growth promoter effects of antibiotics stems from their ability to control microbial populations in the gut, decreasing toxic microbial byproducts and limiting competition for nutrients in the gastrointestinal tract (GIT).2,3 These growth promoting effects have made antibiotics a common feed additive in the poultry industry.4 However, decades of exposing microorganisms to low doses of antibiotics has created a selection pressure for antibiotic-resistant bacteria.5 In a 2017 study in Ghana, over sixty percent of Staphylococci isolates from poultry farms and farm workers were resistant to multiple antibiotics, including tetracycline, one of the most common antibiotics in the poultry industry.6 The European Union banned the use of food animal growth-promoting antibiotics in 1986. In the USA, the guidelines for industry issued by the Center for Veterinary Medicines of the Food and Drug Administration (FDA, 2012) recommend use of antibiotics only for the prevention, control and treatment of infections in animals but not for the promotion of growth, increased performance, and improved feed efficiency. Alternatives to antibiotics are, therefore, needed in order to continue the efficiency and sustainability of the poultry production. A promising alternative is phytogenic essential oil. In this editorial, we will review how the structure of phytochemicals within essential oils contributes to the antimicrobial activity and growth promotion in broilers.

Trichoderma spp. are filamentous fungi which frequently colonise soil and plant roots. As an alternative to chemical pesticides, some Trichoderma species such as T. harzianum, T. atroviride and T. virens are being used as biocontrol... more

Trichoderma spp. are filamentous fungi which frequently colonise soil and plant roots. As an alternative to chemical pesticides, some Trichoderma species such as T. harzianum, T. atroviride and T. virens are being used as biocontrol agents against plant pathogenic fungi. Biocontrol strains of Trichoderma show both, induction of resistance in plants and direct mycoparasitism of plant pathogenic fungi. For both of these processes, the production and secretion of antifungal secondary metabolites such as peptaibols plays a key role. Peptaibols show antimicrobial activity and constitute a large group of more than 300 known different linear peptides with a length of up to 20 amino acid residues, carrying non-proteinogenic amino acids such as α-aminoisobutyric acid (Aib) as well as a modified N-terminus (e.g. acetylation) and a C- terminal amino alcohol (e.g. leucinol). Due to their bioactive properties, peptaibols are interesting target compounds for the development of biocontrol agents a...

One hundred and twenty-five isolates of Micrococcaceae from Italian salami were tested for antagonistic activities against Listeria monocytogenes. Four isolates, identified as Staphylococcus xylosus, inhibited the growth of all five... more

One hundred and twenty-five isolates of Micrococcaceae from Italian salami were tested for antagonistic activities against Listeria monocytogenes. Four isolates, identified as Staphylococcus xylosus, inhibited the growth of all five strains of L. monocytogenes tested. The antagonistic substances produced by strains 39A and 41A were inactivated by some proteases, whereas those from strains 1E and 27E were inactivated only by esterase and lipase. They are neither bacteriophages, nor lytic enzymes like lysostaphin.

A high-throughput mass spectrometry assay to measure the catalytic activity of UDP-3-O-(R-3-hydroxymyristoyl)-N-acetylglucosamine deacetylase, LpxC, is described. This reaction is essential in the biosynthesis of lipopolysaccharide (LPS)... more

A high-throughput mass spectrometry assay to measure the catalytic activity of UDP-3-O-(R-3-hydroxymyristoyl)-N-acetylglucosamine deacetylase, LpxC, is described. This reaction is essential in the biosynthesis of lipopolysaccharide (LPS) of gram-negative bacteria and is an attractive target for the development of new antibacterial agents. The assay uses the RapidFire mass spectrometry platform to measure the native LpxC substrate and the reaction product and thereby generates a ratiometric readout with minimal artifacts due to detection interference. The assay was robust in a high-throughput screen of a library of more than 700,000 compounds arrayed as orthogonal mixtures, with a median Z' factor of 0.74. Selected novel inhibitors from the screening campaign were confirmed as binding to LpxC by biophysical measurements using a thermal stability shift assay. Some inhibitors showed whole-cell antimicrobial activity against a sensitive strain of Escherichia coli with reduced LpxC ...

The Study was mainly aimed to establish the local ethno-medicinal claim of Assam that lemon peel oil has Antimicrobial property. Again when searching for the Microscopic Characters of lemon leaf for identification, data’s were not... more

The Study was mainly aimed to establish the local ethno-medicinal claim of Assam that lemon peel oil has
Antimicrobial property. Again when searching for the Microscopic Characters of lemon leaf for
identification, data’s were not available easily and then the aim of the study was broadened to include
evaluation of pharmacognostic, phytochemical, physicochemical property and to make the data’s available
easily for further use. The Lemon Peel Oil as every other volatile oil has shown antimicrobial activity, but
was active against both Gm +ve and Gm _ve organism. When compared with Standard drug Amoxicillin
the activities were less potent but can be useful if explored either alone or in combination with other
antimicrobial agents.

A vancomicina é um antimicrobiano glicopeptídeco indicado em situações de infecções graves por MSRA, com uso difundido nas UTIs devido, sobretudo, às características assistenciais e ao perfil dos pacientes. No entanto, em virtude de... more

A vancomicina é um antimicrobiano glicopeptídeco indicado em situações de infecções graves por MSRA, com uso difundido nas UTIs devido, sobretudo, às características assistenciais e ao perfil dos pacientes. No entanto, em virtude de apresentar estreita faixa terapêutica, apresenta variações importantes dos seus níveis séricos a partir da existência de algumas condições clínicas. Nesse sentido, o presente estudo teve como objetivo analisar os fatores que podem alterar a concentração sérica de vancomicina em pacientes em UTIs. Foi realizada uma revisão integrativa da literatura, durante março de 2020, nas bases de dados Scientific Electronic Library Online, Medical Literature Analysis and Retrieval System Online e Literatura Latino-Americana e do Caribe em Ciências da Saúde, através de três estratégias de busca formuladas a partir dos Descritores em Ciências da Saúde e cruzadas por meio do operador booleano AND. Foram encontrados 126 artigos, dos quais 32 compuseram o corpus de análise da pesquisa. A análise de conteúdo resultou na construção das categorias Função renal, Sepse, Peso, Idade, Queimadura, Terapias de substituição renal, Proteínas séricas, Ventilação mecânica, Incompatibilidades medicamentosas e Oxigenação por membrana extracorpórea. Observou-se que a existência de variados fatores que alteram a concentração sérica de vancomicina ratifica a necessidade de qualificação das iniciativas de segurança do paciente diante de estratégias que possibilitem o alcance do sucesso clínico e microbiológico da vancomicina.

Eleven essential oils (EOs) were evaluated for their antibacterial properties, against Vancomycin-Resistant Enterococci (VRE) and E. coli O157:H7. EOs were introduced into Brain Heart Infusion agar (BHI) (15ml) at a concentration of 0.25... more

Eleven essential oils (EOs) were evaluated for their antibacterial properties, against Vancomycin-Resistant Enterococci (VRE) and E. coli O157:H7. EOs were introduced into Brain Heart Infusion agar (BHI) (15ml) at a concentration of 0.25 to 2% (vol/vol) to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) for each pathogen evaluated. Results showed that the most active essential oils against bacteria tested were thyme oil, with MIC90 and MBC90 for the VRA strains of 0.25% and 0.5%, respectively. Eucalyptus, juniper and clove oils were the least potent agent, with MIC90 and MBC90 of 2%. Furthermore, the inhibitory effect of these EO were evaluated against VRE and E. coli O157:H7, experimentally inoculated (103 cfu/g) in Feta soft cheese and minced beef meat, which was mixed with different concentrations (0.1%, 0.5% and 1%) of the EO and stored at 7 ºC for 14 days. Out of eucalyptus, juniper, mint, rosemary, sage, clove and thyme oils tested against target bacteria sage and thyme showed the best results. Clove and mint did not show any effect on VRE and E. coli O157:H7 in both kinds of studied foods. The addition of thyme oil at concentrations of 0.5 and 1% caused best significant reduction in the growth rate of VRE and E. coli O157:H7 in cheese and meat at 7 ºC. It is concluded that selected plant EOs can act as potent inhibitors of both microorganisms in a food product. The results revealed the potential of thyme oil as a natural preservative in feta soft cheese and minced beef meat against VRE and E. coli O157:H7 contamination.

The leaves of Persea americana are widely used for ethno-medicinal purposes worldwide. This study assessed the antimicrobial and antioxidant activities of the methanol, ethyl acetate, chloroform and petroleum ether leaves extracts of P.... more

The leaves of Persea americana are widely used for ethno-medicinal purposes worldwide. This study assessed the antimicrobial and antioxidant activities of the methanol, ethyl acetate, chloroform and petroleum ether leaves extracts of P. americana. Extracts displayed variable antimicrobial activities that were microorganism-specific. The methanolic extract displayed the most potent antimicrobial activities with the largest zones of inhibition (0-1.8 mm) in the agar diffusion assay and with the lowest minimum inhibitory concentration (MIC) in the broth dilution assay against a panel of microorganisms that included Bacillus subtilis, Escherichia coli, Salmonella typhi, Streptococcus aureus, Pseudomonas aeruginosa and Candida albicans. The ethyl acetate extract exhibited the most potent antioxidant potential with the lowest EC 50 of 4.15x10-30 g/ml for the peroxide radical scavenging activities. The data supports the ethnomedicinal use of the leaves of P. americana for the management of infections and for other symptoms whose etiology may be linked to oxidative stress.

A facile and inexpensive route has been developed to synthesize a ternary ZnO/Ag/Mn2O3 nanocomposite having nanorod structures based on the thermal decomposition method. The as-synthesized ternary ZnO/Ag/Mn2O3 nanocomposite was... more

A facile and inexpensive route has been developed to synthesize a ternary ZnO/Ag/Mn2O3 nanocomposite having nanorod structures based on the thermal decomposition method. The as-synthesized ternary ZnO/Ag/Mn2O3 nanocomposite was characterized and used for visible light-induced photocatalytic, sensing and antimicrobial studies. The ternary ZnO/Ag/Mn2O3 nanocomposite exhibited excellent and enhanced visible light-induced photocatalytic degradation of industrial textile effluent (real sample analysis) compared to pure ZnO. Sensing studies showed that the ternary ZnO/Ag/Mn2O3 nanocomposite exhibited outstanding and improved detection of uric acid (UA) and ascorbic acid (AA). It also showed effective and efficient bactericidal activities against Staphylococcus aureus and Escherichia coli. These results suggest that the small size, high surface area and synergistic effect among ZnO, AgNPs and Mn2O3 induced visible light photocatalytic activity by decreasing the recombination of photogenerated electrons and holes, and extending the response of pure ZnO to visible light, enhanced sensing of UA and AA and antimicrobial activity. Overall, the ternary ZnO/Ag/Mn2O3 nanocomposite is a valuable material that can be used for a range of applications, such as visible light-induced photocatalysis, sensing and antimicrobial activity. Therefore, ternary nanocomposites could have important applications in environmental science, sensing, and biological fields.