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1.
Crit Rev Microbiol ; 40(1): 49-62, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23363325

RESUMO

Numerous coelomycetous fungi classified in Ascochyta, Phoma and Phyllosticta, and lately established and/or re-classified genera and species, namely Boeremia and Peyronellaea have been recorded from spots on leaves and pods of soybeans. These rarely observed pathogens are cosmopolitan, ubiquitous species on diseased and dead plant materials, and define frequently as weak or opportunistic parasites. Based on the Genealogical Concordance Phylogenetic Species Recognition, the authors summarize the re-evaluation of the taxonomic status of Phoma sojicola (syn. Ascochyta sojicola) and Phyllosticta sojicola. Inspite of the former delimitation of Ph. sojicola based on small differences in morphological features, it has proved to be identical to Peyronellaea pinodella (syn. Phoma pinodella). Similarly, it was also confirmed that Ph. sojicola was identical to Boeremia exigua var. exigua (syn. Phoma exigua var. exigua). The authors and co-workers contributed to the identification of Phoma-like fungi by combined conventional and molecular methods. Protein-encoding genes (TEF1 and ß-tubulin) were successfully applied within the Phoma genus to infer phylogenetic relationships.


Assuntos
Ascomicetos/classificação , Ascomicetos/isolamento & purificação , Glycine max/microbiologia , Doenças das Plantas/microbiologia , Ascomicetos/genética , DNA de Plantas/genética , DNA Espaçador Ribossômico/genética , Frutas/microbiologia , Fator 1 de Elongação de Peptídeos/genética , Filogenia , Folhas de Planta/microbiologia , Homologia de Sequência , Tubulina (Proteína)/genética
2.
ScientificWorldJournal ; 2013: 796018, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24222751

RESUMO

Synthesis of silver nanoparticles (SNPs) by fungi is emerging as an important branch of nanotechnology due to its ecofriendly, safe, and cost-effective nature. In order to increase the yield of biosynthesized SNPs of desired shape and size, it is necessary to control the cultural and physical parameters during the synthesis. We report optimum synthesis of SNPs on malt extract glucose yeast extract peptone (MGYP) medium at pH 9-11, 40-60°C, and 190.7 Lux and in sun light. The salt concentrations, volume of filtrate and biomass quantity were found to be directly proportional to the yield. The optimized conditions for the stable and rapid synthesis will help in large scale synthesis of monodispersed SNPs. The main aim of the present study was to optimize different media, temperature, pH, light intensity, salt concentration, volume of filtrate, and biomass quantity for the synthesis of SNPs by Fusarium oxysporum.


Assuntos
Fusarium/crescimento & desenvolvimento , Nanopartículas Metálicas/química , Prata/química , Meios de Cultura
3.
Int J Med Mushrooms ; 14(5): 481-90, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23510217

RESUMO

Antibacterial activity of Lingzhi or Reishi medicinal mushroom, Ganoderma lucidum, collected from Central India was evaluated against four bacterial pathogens. Ethyl alcohol and water extracts of fruit body powder were tested using the disc diffusion method against Staphylococcus aureus, Klebsiella pneumoniae, Bacillus cereus, and Pseudomonas aeruginosa. It was noted that the aqueous extract inhibited growth of pathogenic bacteria. The combined effect of fruit body extract with synthetic antibiotic discs was found to increase the activity significantly more than the antibiotics alone. The present study is an attempt to assess antibacterial activity of extracts of G. lucidum singly and in combination. The combination of G. lucidum with commercial antibiotics proves that it enhances antibacterial activity.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Reishi/química , Testes de Sensibilidade Microbiana
4.
Chemosphere ; 291(Pt 2): 132676, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34718020

RESUMO

The microbial infections due to biofilm forming bacterial pathogens are very common in human subjects. The intensive application of antibiotics in integrated disease management strategy has led to increased multidrug resistance incommon pathogens. Thus, indicating need of developing an alternative method for the control of these multidrug resistant pathogens. Present study involves the Moringa oleifera aqueous extract mediated biological synthesis of silver (Ag nanoparticles (NPs)- Avg. size 82.5 nm; zeta potential = -27.9 mV), copper oxide (CuONPs- Avg. size 61 nm; zeta potential = -19.3 mV), iron oxide (FeONPs- Avg. size 83.3 nm; zeta potential = -9.37 mV) and alumina (AlONPs- Avg. size 87.3 nm; zeta potential = -10.9 mV) nanoparticles. Biological nanoparticles were detected by visual observation, spectrophotometric detection followed by zeta potential analysis, nanoparticle tracking analysis, Fourier transform infrared spectrometry and X-ray diffraction analysis. Nanoparticles were further evaluated for their in vitro antimicrobial potential, membrane damage effectiveness, biofilm inhibition activity by MTT assay. Nanoparticles were assessed against human pathogens viz. two Gram-positive (Bacillus subtilis MTCC 441 and Staphylococcus haemolyticus MTCC 3383) and two Gram-negative bacteria (Enterobacter aerogenes MTCC 111 and Salmonella enterica ser. Typhi MTCC 8767). The nanoparticles exhibited akin activity pattern against all pathogens studied i.e. AgNPs > CuONPs > AlONPs > FeONPs. Tested nanoparticles registered lower MIC values and more intensified growth inhibition against Gram-negative bacteria compared to their Gram-positive counterparts. These results pointed out that the M. oleifera mediated nanoparticles can be prospectivelyutilized in the development of alternative antimicrobials against diverse bacterial infections.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Antibacterianos/farmacologia , Bactérias , Humanos , Testes de Sensibilidade Microbiana , Extratos Vegetais , Prata , Espectroscopia de Infravermelho com Transformada de Fourier
5.
Int J Med Mushrooms ; 13(5): 483-91, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22324414

RESUMO

Lingzhi or Reishi medicinal mushroom, Ganoderma lucidum, has been used over the ages as highly medicinal herb in the Orient. Many useful properties of this fungus are still being studied; we report here a new facet of this "elixir of life" as a mycosource for synthesis of metal nanoparticles. Treating the extracellular suspension filtrate of the mycelia of G. lucidum with silver nitrate reduces the metal ions to nanoparticles. Optical detection followed by confirmation through spectroscopic analysis suggests that this fungus can be used for the purpose of safe and sure synthesis of silver nanoparticles, demand for which is growing day by day in all fields of human life. LM-20 analysis of these G. lucidum-synthesised nanoparticles reveals the polydispersity and distribution of silver nanoparticles in the range of 10-70 nm with an average size of 45 nm and a concentration of 0.37 x 108 particles/mL. FT-IR spectrum confirms the stability of these nanoparticles due to presence of amide linkages and protein capping. These nanoparticles have shown strong bactericidal activity against test pathogens Staphylococcus aureus and Escherichia coli, and also exhibited their efficiency in enhancing the activity of the synthetic antibiotic tetracycline. The method of synthesising silver nanoparticles and its bactericidal effect discussed here can be used for environment-friendly and economically feasible production for different applications where chemically synthesized nanoparticles cause undesirable effects.


Assuntos
Antibacterianos/metabolismo , Antibacterianos/farmacologia , Ganoderma/metabolismo , Nanopartículas Metálicas/química , Prata/química , Prata/metabolismo , Antibacterianos/química , Escherichia coli , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacos
6.
Int J Antimicrob Agents ; 32(2): 180-5, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18571386

RESUMO

A polyherbal cream (Basant) has been formulated using diferuloylmethane (curcumin), purified extracts of Emblica officinalis (Amla), purified saponins from Sapindus mukorossi, Aloe vera and rose water along with pharmacopoeially approved excipients and preservatives. Basant inhibits the growth of WHO strains and clinical isolates of Neisseria gonorrhoeae, including those resistant to penicillin, tetracycline, nalidixic acid and ciprofloxacin. It has pronounced inhibitory action against Candida glabrata, Candida albicans and Candida tropicalis isolated from women with vulvovaginal candidiasis, including three isolates resistant to azole drugs and amphotericin B. Basant displayed a high virucidal action against human immunodeficiency virus HIV-1NL4.3 in CEM-GFP reporter T and P4 (Hela-CD4-LTR-betaGal) cell lines with a 50% effective concentration (EC50) of 1:20000 dilution and nearly complete (98-99%) inhibition at 1:1000 dilution. It also prevented the entry of HIV-1(IIIB) virus into P4-CCR5 cells (EC50 approximately 1:2492). Two ingredients, Aloe and Amla, inhibited the transduction of human papillomavirus type 16 (HPV-16) pseudovirus in HeLa cells at concentrations far below those that are cytotoxic and those used in the formulation. Basant was found to be totally safe according to pre-clinical toxicology carried out on rabbit vagina after application for 7 consecutive days or twice daily for 3 weeks. Basant has the potential of regressing vulvovaginal candidiasis and preventing N. gonorrhoeae, HIV and HPV infections.


Assuntos
Anti-Infecciosos/farmacologia , Candida/efeitos dos fármacos , HIV-1/efeitos dos fármacos , Papillomavirus Humano 16/efeitos dos fármacos , Neisseria gonorrhoeae/efeitos dos fármacos , Extratos Vegetais/farmacologia , Aloe/química , Animais , Anti-Infecciosos/toxicidade , Curcumina/química , Feminino , Doenças dos Genitais Femininos/microbiologia , Doenças dos Genitais Femininos/virologia , Células HeLa , Humanos , Phyllanthus emblica/química , Fitoterapia , Extratos Vegetais/toxicidade , Coelhos , Sapindus/química , Cremes, Espumas e Géis Vaginais
7.
Int J Med Mushrooms ; 17(10): 921-32, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26756184

RESUMO

Ganoderma spp. are very important therapeutic mushrooms and have been used traditionally for 4000 years in the treatment of various human disorders. Different species of Ganoderma possess bioactive compounds, which have already demonstrated antiviral, antibacterial, and antifungal activities. Various bioactive compounds such as triterpenoids, colossolactones, and polysaccharides, which are responsible for the antimicrobial potential of the genus, are discussed here in detail. Some Ganoderma spp. have been reported to be potential agents for the synthesis of metal nanoparticles. These nanoparticles have demonstrated antimicrobial activity and also are reviewed herein. The main aim of this review is to discuss the possible use of Ganoderma extracts and their active principles in antimicrobial therapy.


Assuntos
Anti-Infecciosos , Ganoderma/química , Animais , Humanos
8.
IET Nanobiotechnol ; 7(1): 28-32, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23705290

RESUMO

Till date several methods of chemical synthesis of silver nanoparticles (AgNps) are known. Most of the protocol dealing with the chemical synthesis of AgNps involves high pressure, temperature, energy and technical skills. Thus, a method with much greener approach is the need of the hour. Accordingly, the authors have developed a method that is cost-effective, energy-efficient and easy method for the synthesis of AgNps. The AgNps were synthesised by using white sugar and sodium hydroxide (NaOH) in the presence of sunlight. These nanoparticles were characterised by visual observation, ultraviolet-visible (UV-vis) spectrophotometry, Fourier transform infrared (FTIR), nanoparticle tracking and analysis (NTA) and transmission electron microscopy (TEM). The effect of NaOH on the rate of AgNps synthesis was also studied. Formation of AgNps was primarily detected by change in colour of reaction mixture from colourless to yellow after treatment with 1 mM silver salt (AgNO3). UV-vis spectroscopy showed peak at 409 nm. NTA revealed the polydispersed nature of nanoparticles, 15-30 nm in diameter. FTIR showed the presence of gluconic acid as capping agent, which increases the stability of AgNps in the colloids. TEM demonstrated the presence of spherical AgfNps in the range of 10-25 nm. The present method confirms the synthesis of AgNps by using white sugar and NaOH. This method is simple, eco-friendly and economically sustainable, making it amenable to large-scale industrial production of AgNps.


Assuntos
Química Verde/métodos , Nanopartículas Metálicas/química , Nanotecnologia/métodos , Prata/química , Sacarose/química , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Transmissão , Hidróxido de Sódio/química , Análise Espectral , Luz Solar
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