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1.
Arch Microbiol ; 204(3): 159, 2022 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-35113233

RESUMO

Extensive use of pesticides has led to the contamination of ecosystem. Therefore, it is important to isolate potential new pesticide-degrading bacteria. For the biodegradation of α-endosulfan and α-cypermethrin, a new bacterium was isolated from the body microflora of grasshopper (Poecilimon tauricola). Based on biochemical, morphological, and 16S rRNA sequence analysis, the isolated strain B7 was identified as Acinetobacter schindleri. This bacterial strain was screened for its α-cypermethrin and α-endosulfan degrading potential with minimal salt medium (MSM) and non-sulfur medium (NSM), respectively. When glucose was added to non-sulfur medium containing α-endosulfan (100 mg/L) and minimal salt medium containing α-cypermethrin (100 mg/L), both pesticide degradation and bacterial growth were increased. Acinetobacter schindleri B7 was able to degrade 67.31% of α-endosulfan and 68.4% of α-cypermethrin within 10 days. The degradation products of pesticides were determined by HPLC. As a result, A. schindleri, a Gram-negative bacterium, can inevitably be used in the biological treatment of environments exposed to pesticides.


Assuntos
Endossulfano , Gafanhotos , Acinetobacter , Animais , Biodegradação Ambiental , Ecossistema , Piretrinas , RNA Ribossômico 16S/genética , Microbiologia do Solo
2.
Prep Biochem Biotechnol ; 45(6): 596-604, 2015 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-25036570

RESUMO

Inulinase production by Rhodotorula glutinis was carried out in this study, using leek (Allium ampeloprasum var. porrum) as an alternative carbon source due to its high inulin content and easy availability. Taguchi orthogonal array (OA) design of experiment (DOE) was used to optimize fermentation conditions. For this purpose, five influential factors (leek concentration, pH, incubation temperature, agitation speed, and fermentation time) related to inulinase production were selected at four convenient levels. The results showed that maximum inulinase activity was obtained as 30.89 U/mL, which was close to the predicted result (30.24 U/mL). To validate the obtained results, analysis of variance (ANOVA) was employed. Consequently, leek has a great potential as an effective and economical carbon source for inulinase production, and the use of Taguchi DOE enhanced enzyme activity about 2.87-fold when compared with the unoptimized condition.


Assuntos
Allium/microbiologia , Reatores Biológicos/microbiologia , Insulisina/biossíntese , Insulisina/isolamento & purificação , Rhodotorula/enzimologia , Rhodotorula/crescimento & desenvolvimento
3.
Toxicol Ind Health ; 29(9): 792-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22514118

RESUMO

Single-cell protein (SCP) refers to the dried cells of microorganisms. The aim of this research was to evaluate the nutrional characteristics and possible toxic effects of the SCP of Trichoderma harzianum. First, T. harzianum was grown on whey filtrate agar medium and the obtained SCP was analysed. It was rich in both total protein (34.21%) and ash (4.78%). Furthermore, the biomass contained all the essential amino acids, and the amino acid concentrations were very close to the FAO reference protein levels. Second, we exposed zebrafish (Danio rerio) embryos to diluted SCP at various concentrations for 96 hours postfertilization (hpf). Compared with the control group, we did not observe any developmental abnormalities, delayed hatching, and lethal effects on zebrafish embryos (96 hpf) found in the SCP group. To test diet effects on spawning success and growth of embryos, adult zebrafish were fed on SCP and flake feed diets for 10 weeks. The number of laid eggs, wet weight and diameter of eggs, and the percentages of hatched eggs from fish fed the flake diet and SCP diet were not significantly different from each other. Also, larval length and weight were not significantly affected by diets. Finally, SCP did not cause any toxic effect on zebrafish adults and their offsprings and could be useful as fish food or food additive.


Assuntos
Ração Animal , Proteínas Alimentares/administração & dosagem , Proteínas Alimentares/efeitos adversos , Testes de Toxicidade/métodos , Peixe-Zebra/crescimento & desenvolvimento , Animais , Biomassa , Peso Corporal/efeitos dos fármacos , Cruzamento , Feminino , Larva/efeitos dos fármacos , Masculino , Trichoderma
4.
Turk J Chem ; 44(3): 589-601, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33488179

RESUMO

Four linear nonphenolic diarylheptanoids were synthesized and their antibacterial activities were studied. ( S )-2-Me-CBS-catalysed reduction of alnustone with BH3SMe2 gave ( R )(-)(4 E ,6 E )-1,7-diphenylhepta-4,6-dien-3-ol, a natural product. Reduction of alnustone with Na in t -BuOH at -15 °C under N3 atm gave (E)-1,7-diphenylhept-5- en-3-one as a Birch-type reduction product. t-BuOK catalysed condensation of benzalacetone with propionyl chloride gave (4 Z ,6 E )-5-hydroxy-1,7-diphenylhepta-4,6-dien-3-one, a natural product. (1 E ,4 Z ,6 E )-5-Hydroxy-4-phenethyl-1,7-diphenylhepta-1,4,6-trien-3-one, a curcuminoid, was synthesized starting from pentan-2,4-dione in 3 steps. The synthesized chemical compounds were applied against 2 gram-positive bacteria ( Bacillus cereus and Arthrobacter agilis ), 4 gram-negative bacteria ( Pseudomonas aeruginosa , Xanthomonas campestris , Klebsiella oxytoca , and Helicobacter pylori ), and 1 yeast (Candida albicans) by the disc diffusion method. All of the synthesized compound exhibited different degrees of antimicrobial activity at concentrations between 20-100 µg/disc against the test organisms.

5.
J Pathog ; 2017: 7628175, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29250446

RESUMO

This study was conducted to assess highly pathogenic Beauveria bassiana isolates to be used in biocontrol and to determine their potentials as mycopesticide. For this purpose, two B. bassiana isolates, which were locally isolated from T. urticae, were chosen. Firstly, three suspensions were investigated at the degree of humidity of 65 ± 5% and 100% RH. Secondly, these strains were selected according to their tendency to mass production, tolerance to UV radiation, and capability of producing spore at the different temperatures. Finally, identification of the selected isolate was performed by using ITS rDNA analysis. Both tested fungal isolates were pathogenic to the T. urticae. Mycelial growths of isolate AT076 at 20°C and 30°C were found to be greater than isolate AT007. It was observed that isolate AT076 had more spore production with 1.61 × 107 spore/disc at 30°C and 44.33% germination after UV radiation for 15 min. The numbers of spores per 5 mm disk area for isolates AT076 and AT007 were found to be 1.2 × 106 and 1.0 × 106. These results show that isolate AT076 was more virulent and more UV-tolerant and had higher tendency to mass production compared to isolate AT007 against T. urticae. As a result of this study, isolate AT076 can be used in the biocontrol as mycopesticide.

6.
3 Biotech ; 7(2): 113, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28567625

RESUMO

Stenotrophomonas maltophilia OG2 was isolated from the intestine of cockroaches that was collected from a cow barn contaminated some pesticides belong to pyrethroid and organochlorine groups. OG2 was able to degrade α-endosulfan in non sulfur medium (NSM) as a sole sulfur source for growth within 10 days of incubation. The effects of some growth parameters on endosulfan biodegradation by OG2 was studied and found that the biodegradation was significantly affected by the endosulfan concentrations, pH and temperature. Experimental results obtained in different conditions show that the optimum concentration of α-endosulfan, pH and temperature were 100 mg/L, 8.0 and 30 °C, respectively. Under these conditions, the bacterium degraded 81.53% of the α-endosulfan after 10 days. The concentration of α-endosulfan and its metabolites was determined by HPLC. Endosulfan ether, endosulfan lactone and endosulfan diol were the main metabolites in culture, but did not produce toxic metabolite, endosulfan sulfate. These results suggested that S. maltophilia OG2 degrades α-endosulfan via a hydrolysis pathway. The present study indicates that strain OG2 may have potential use in the biodegradation of pesticides contaminated environments.

7.
3 Biotech ; 7(1): 23, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28401461

RESUMO

Indole acetic acid (IAA) is a plant growth-promoting hormone used in agriculture; therefore, its continuous production is of paramount importance. IAA-producing eight bacteria were isolated from the rhizosphere of Verbascum vulcanicum. Among them, Arthrobacter agilis A17 gave maximum IAA production (75 mg/L) and this strain was used to immobilization studies. The A. agilis A17 cells were immobilized in calcium alginate for the production of IAA. Optimization of process parameters for IAA production was carried out to enhance IAA production using immobilized cells. The maximal production of IAA was 520 mg/L under the following optimal conditions: 1% mannitol, 30 °C, pH 8.0, and 24 h incubation. It was determined that the immobilized cells could be reused (13 times) for the production of IAA.

8.
Bioresour Technol ; 97(4): 599-604, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15922594

RESUMO

Heads of sunflower (Helianthus annuus L.) were first biodegraded at 55 degrees C by their microflora. Biodegradation products of sunflower heads (BPSH) were analyzed. They were found to contain 9.77% dry matter, 3.98% total ash, 3.18% crude protein and 5.75% total organic matter. BOD load was determined as 4.80 g/100 g. Subsequently, the effects of BPSH at various concentrations (1.0%, 2.5%, 10% and 100%) on the seed germination and some growth parameters of Phaseolus vulgaris L., Cicer arietinum L. and Triticum vulgare L. were investigated. The percentages of seed germination and germination index of seeds were similar between the control and 1.0% and 2.5% BPSH groups, but these values decreased at higher concentrations. On the other hand, growth of the seedlings gradually increased up to a concentration of 10% BPSH and decreased at 100% concentration. As a result, at concentrations up to 10% the product was found to be beneficial for growth of plants.


Assuntos
Agricultura/métodos , Produtos Agrícolas/crescimento & desenvolvimento , Flores/metabolismo , Helianthus/metabolismo , Biodegradação Ambiental , Flores/química , Germinação/fisiologia , Helianthus/química
9.
Mater Sci Eng C Mater Biol Appl ; 56: 432-7, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26249611

RESUMO

A commercial strain of Gluconobacter oxydans together with a new co-polymer Poly(glycidyl methacrylate-co-3-thienylmethylmethacrylate) (Poly(GMA-co-MTM)), which provides effective immobilization in the continuous flow system, was used in the sensor design. By taking the advantages of the nano-technology, carbon nanotubes (CNTs) were also added to the cell film and the sensitivity of the sensor was increased about 15 times. During the glycerol analysis in the continuous system, it was shown that composite film was not removed from the electrode surface and film elements were not washed out from the system. Glycerol analyses were performed by using batch loaded continuously flow cell at different flow rates of 1, 2, 4, and 6mL/min. The linear range was found as 2-100mM with the detection limit (LOD) of 0.057mM according to S/N=3. The calibration graphs were obtained for Poly(GMA-co-MTM)/G. oxydans and Poly(GMA-co-MTM)/CNT/G. oxydans biofilm electrodes in FIA mode, and sensitivities were found to be 1.50nA/mM and 19.13nA/mM, respectively. In this study, Poly(GMA-co-MTM) was used for the first time as a microbial matrix and was shown to be an effective immobilization agent.


Assuntos
Técnicas Biossensoriais , Gluconobacter oxydans/metabolismo , Glicerol/análise , Membranas Artificiais , Metilmetacrilatos/química , Eletrodos
10.
Braz J Microbiol ; 46(2): 631-7, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26273284

RESUMO

This work addresses the production of prodigiosin from ram horn peptone (RHP) using MO-1, a local isolate in submerged culture. First, a novel gram-negative and rod-shaped bacterial strain, MO-1, was isolated from the body of the grasshopper (Poecilemon tauricola Ramme 1951), which was collected from pesticide-contaminated fields. Sequence analysis of 16S rDNA classified the microbe as Serratia marcescens. The substrate utilization potential (BIOLOG) and fatty acid methyl ester profile (FAME) of S. marcescens were also determined. The effect of RHP on the production of prodigiosin by S. marcescens MO-1 was investigated, and the results showed that RHP supplementation promoted the growth of MO-1 and increased the production of prodigiosin. A concentration of 0.4% (w/v) RHP resulted in the greatest yield of prodigiosin (277.74 mg/L) after 48 h when mannitol was used as the sole source of carbon. The pigment yield was also influenced by the types of carbon sources and peptones. As a result, RHP was demonstrated to be a suitable substrate for prodigiosin production. These results revealed that prodigiosin could be produced efficiently by S. marcescens using RHP.


Assuntos
Meios de Cultura/química , Peptonas/metabolismo , Prodigiosina/metabolismo , Serratia marcescens/crescimento & desenvolvimento , Serratia marcescens/metabolismo , Animais , Técnicas de Tipagem Bacteriana , Análise por Conglomerados , Citosol/química , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Ácidos Graxos/análise , Gafanhotos/microbiologia , Dados de Sequência Molecular , Filogenia , Pigmentos Biológicos/metabolismo , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Serratia marcescens/classificação , Serratia marcescens/isolamento & purificação
11.
Bioresour Technol ; 85(2): 125-9, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12227535

RESUMO

Ram horns obtained from the slaughterhouse of Erzurum, Turkey were hydrolyzed by treating with acid (6N-HCl) and ram horn hydrolysate (RHH) was obtained. The hydrolysate was used as substrate to grow Bacillus cereus NRRL B-3711, Bacillus subtilis NRRL NRS-744 and Escherichia coli in batch system at 30 degrees C; air 1.5 v/v/min; stirring 150 rpm. Both RHH and biomass samples were analyzed. The bacterial cells produced in this hydrolysate were found to be rich in total protein (66%, 68% and 71% for E. coli, B. cereus and B. subtilis, respectively). The chemical oxygen demand and biological oxygen demand were reduced significantly by the growth of bacteria. The protein produced contained all essential amino acids for ruminant feed.


Assuntos
Bactérias/metabolismo , Aminoácidos/metabolismo , Ração Animal , Animais , Bacillus cereus/metabolismo , Bacillus subtilis/metabolismo , Escherichia coli/metabolismo , Fermentação , Hidrólise , Oxigênio/metabolismo , Ovinos
12.
Braz. j. microbiol ; 46(2): 631-637, Apr-Jun/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-749708

RESUMO

This work addresses the production of prodigiosin from ram horn peptone (RHP) using MO-1, a local isolate in submerged culture. First, a novel gram-negative and rod-shaped bacterial strain, MO-1, was isolated from the body of the grasshopper (Poecilemon tauricola Ramme 1951), which was collected from pesticide-contaminated fields. Sequence analysis of 16S rDNA classified the microbe as Serratia marcescens. The substrate utilization potential (BIOLOG) and fatty acid methyl ester profile (FAME) of S. marcescens were also determined. The effect of RHP on the production of prodigiosin by S. marcescens MO-1 was investigated, and the results showed that RHP supplementation promoted the growth of MO-1 and increased the production of prodigiosin. A concentration of 0.4% (w/v) RHP resulted in the greatest yield of prodigiosin (277.74 mg/L) after 48 h when mannitol was used as the sole source of carbon. The pigment yield was also influenced by the types of carbon sources and peptones. As a result, RHP was demonstrated to be a suitable substrate for prodigiosin production. These results revealed that prodigiosin could be produced efficiently by S. marcescens using RHP.


Assuntos
Animais , Meios de Cultura/química , Peptonas/metabolismo , Prodigiosina/metabolismo , Serratia marcescens/crescimento & desenvolvimento , Serratia marcescens/metabolismo , Técnicas de Tipagem Bacteriana , Análise por Conglomerados , Citosol/química , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Ácidos Graxos/análise , Gafanhotos/microbiologia , Dados de Sequência Molecular , Filogenia , Pigmentos Biológicos/metabolismo , /genética , Análise de Sequência de DNA , Serratia marcescens/classificação , Serratia marcescens/isolamento & purificação
13.
Pak J Biol Sci ; 10(10): 1708-12, 2007 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-19086522

RESUMO

In this study the effects of some selected medical plants (Pimpinella anisum L., Rosmarinus officinalis L., Achillea millefolium L., Acorus calamus L., Hypericum perforatum L.) on the development of Drosophila melanogaster have been investigated. When the different concentration of plant extracts were applied to the cultures of Drosophila melanogaster, they did not caused an elongation of metamorphosis of F1 progeny. Furthermore, depending on an increase of plant extract on the application groups, the number of offsprings increased. But this increasing (for application groups no. I, II and IV) was not statistically significant (p > 0.05) according to control group. The highest increase in the total number of offspring of F1 progeny obtained from applications of Acorus calamus extracts and the 10 mL/100 mL medium concentration of the extract of Hypericum perforatum.


Assuntos
Drosophila melanogaster/efeitos dos fármacos , Extratos Vegetais/química , Plantas Medicinais/química , Teratogênicos/toxicidade , Animais , Drosophila melanogaster/crescimento & desenvolvimento
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