Galba Maria de Campos Takaki

Role of the Morphology and Polyphosphate in Trichoderma harzianum Related to Cadmium Removal

This study concerns the metabolism of polyphosphate in Trichoderma harzianum, a biocontrol agent with innate resistance against most chemicals used in agriculture, including metals, when grown in the presence of different concentrations of cadmium. The biomass production was affected by the concentration of metal used. Control cultures were able to accumulate polyphosphate under the conditions used. Moreover, the presence of cadmium induced a reduction in polyphosphate content related to the concentration used. The morphological/ultrastructural aspects were characterized by using optical and scanning electron microscopy, and were affected by the heavy metal presence and concentration. The efficiency of cadmium removal revealed the potential of the microorganism for use in remediation. The data indicate the potential for polyphosphate accumulation by the fungus, as well as its degradation related to tolerance/survival in the presence of cadmium ions.

A new indoloditerpene derivative, penijanthine A, isolated from Penicillium janthinellum

In a screen searching for new bioactive agents, a new indoloditerpene, penijanthine A (1), was isolated from Penicillium janthinellum IFM 55557. The structure of 1 was established on the basis of spectroscopic and chemical investigation, as well as detailed comparison with the spectroscopic and physico-chemical data of paxilline (2), which was isolated along with 1.

Cadmium Tolerance and Removal from Cunninghamella elegans Related to the Polyphosphate Metabolism

The aim of the present work was to study the cadmium effects on growth, ultrastructure and polyphosphate metabolism, as well as to evaluate the metal removal and accumulation by Cunninghamella elegans (IFM 46109) growing in culture medium. The presence of cadmium reduced growth, and a longer lag phase was observed. However, the phosphate uptake from the culture medium increased 15% when compared to the control. Moreover, C. elegans removed 70%–81% of the cadmium added to the culture medium during its growth. The C. elegans mycelia showed a removal efficiency of 280 mg/g at a cadmium concentration of 22.10 mg/L, and the removal velocity of cadmium was 0.107 mg/h. Additionally, it was observed that cadmium induced vacuolization, the presence of electron dense deposits in vacuoles, cytoplasm and cell membranes, as well as the distinct behavior of polyphosphate fractions. The results obtained with C. elegans suggest that precipitation, vacuolization and polyphosphate fractions were associated to cadmium tolerance, and this species demonstrated a higher potential for bioremediation of heavy metals.

Eliminação de resistência a drogas por fluorquinolonas em Staphylococcus aureus de origem bovina

Bovine strains of Staphylococcus aureus were submitted to treatment with four fluoro-quinolones in subinhibitory concentrations (1/2 x MICs) to evaluate their influence on the curing of plasmids. Ciprofloxacin showed to be the most efficient by eliminating resistance to streptomycin, tetracyclin, penicillin, and cadmium nitrate. Norfloxacin and pefloxacin eliminated penicillin- and tetracyclin-resistance respectively. Otherwise, plasmids elimination by ofloxacin was not evidenced. The results obtained in this study confirm the potential of fluoroquinolones to eliminate antibiotic-resistant plasmids, and showed to be a valuable contribution for the prevention of multi-resistant strains, and may even enhance their sensitivity to other chemotherapeutic agents.

Hybrid microbial-photosynthetic biofuel cells for simultaneous bacterial glycerol biotransformation and algal carbon dioxide capture

Power generation at bioanodes of Pseudomonas aeruginosa for glycerol biotransformation was coupled to the carbon dioxide capture in biocathodes of Chlorella vulgaris in hybrid photosynthetic biofuel cells (HPSBC). Biochemical parameters such as microbial growth, substrate consumption, production of bacterial pigments and CO2 capture were studied. Also electrochemical parameters of maxima current densities (Idmax), power output (Pdmax) and coulombic efficiencies (CE) were studied. Initially, both systems were evaluated in separate against the corresponding Fe3+|Fe2+ redox pair. In bacterial systems, important results in terms of Idmax of 42 ± 2.1 µA cm-2, CE of 48 ± 2.4% and Pdmax of 350 ± 17.5 mW cm-2 were achieved. Likewise, for isolated algal cathode systems, Idmax of 93 ± 4.65 µA cm-2, CE of 56 ± 2.8% and Pdmax of 3.2 ± 0.16 mW cm-2, were achieved. In contrast, when both systems were coupled, a lower Idmax of 48.5 ± 2.42 µA cm-2 was observed. Finally, bioelectrochemical conditions were improved based on substrate consumption, electrogenic products, cation transport and mediated electron transfer systems. Thus, higher average values for Idmax of 80 ± 4.0 µA cm-2, CE of 71.5 ± 3.57% and Pdmax of 650 ± 32.5 mW cm-2 were obtained.

Plantas de cana-de-açúcar cultivadas in vitro com antibióticos

A contaminacao por microrganismos e conhecida como um dos mais serios problemas da cultura de tecidos de plantas, especialmente, em especies tropicais. Com o objetivo de eliminar bacterias endofiticas, propagulos das cultivares de cana-de-acucar Co 997, SP 70-1143 e apices caulinares isolados de plantas, provenientes de semente botânica biparental (RB 818004 x SP 71-6949), foram cultivados in vitro, em meios de cultivo com antibioticos. No primeiro experimento, propagulos das cultivares Co 997 e SP 70-1143 foram cultivados em meio de cultivo contendo 200 e 300 mg.L-1 de amoxicilina e cefatoxima sodica durante 30 dias. Num segundo experimento, utilizou-se apenas a amoxicilina em concentracoes mais elevadas ( 300, 600 e 1000 mg.L-1), com as mesmas plantas utilizadas no primeiro experimento, permanecendo em cultivo por mais 30 dias. No terceiro experimento foram utilizados apices caulinares isolados de plantas provenientes de semente botânica biparental (RB 818004 x SP 71-6949), cultivados em meio de cultivo contendo 1000 mg.L-1 de amoxicilina, por um periodo de 120 dias. Apos estes periodos de cultivo, testes de infeccao e observacoes histologicas revelaram que o isolamento do apice caulinar associado ao uso de antibiotico no meio de cultivo nao foi suficiente para eliminar as bacterias endofiticas.

Copper influence on polyphosphate metabolism of Cunninghamella elegans

The aim of this work was to evaluate the physiological aspects of polyphosphate metabolism of Cunninghamella elegans grown in presence of copper. The growth profile was obtained by means of biomass yields, orthophosphate consumption, polyphosphate accumulation and phosphatases activities. The results revealed the influence of copper on the growth, observed by biomass yields. Orthophosphate consumption was faster in cells grown in the presence of copper. The presence of copper in the culture medium induced polyphosphate accumulation. The polyphosphate level was almost constant in the beginning of control culture growth, and could be related to the exponential growth phase. On the other hand, the copper treated cultures exhibited a significant reduction in the polyphosphate levels, indicating an active metabolization of the polymer. Acid phosphatase activity was not detected in the conditions studied, but alkaline phosphatase activity was significantly lower in the treated cultures. The results suggest the potential use of Cunninghamella elegans isolate in bioremediation and biosorption applied to environments polluted by copper.

Optimization of production, biochemical characterization and in vitro evaluation of the therapeutic potential of fibrinolytic enzymes from a new Bacillus amyloliquefaciens

The capacity of fibrinolytic enzymes to degrade blood clots makes them of high relevance in medicine and in the pharmaceutical industry. In this work, forty-three microorganisms of the genus Bacillus were evaluated for their potential to produce fibrinolytic proteases. Thirty bacteria were confirmed as producers of fibrinolytic enzymes, the best results obtained for the strain Bacillus amyloliquefaciens UFPEDA 485. The optimization of the enzyme production conditions was done by a central composite design (CCD) star 23 that allowed to define the optimal conditions for soybean flour and glucose concentrations and agitation rate. The highest fibrinolytic activity (FA) of 813 U mL–1 and a degradation of blood clot in vitro of 62% were obtained in a medium with 2% (w/v) of soybean flour and 1% (w/v) glucose at 200 rpm after 48 h of cultivation, at pH 7.2 and 37 °C. The obtained fibrinolytic enzyme was characterized biochemically. Fibrinolytic activity was inhibited by PMSF (fluoride methylphenylsulfonyl - C7H7FO2S) 91.52% and EDTA (ethylenediaminetetraacetic acid - C10H16N2O8) 89.4%, confirming to be a serine-metallo protease. The optimum pH and temperature were 7.0 and 37 oC, respectively, and the enzyme was stable for 12 h. The fibrinolytic activity at physiological conditions of this enzyme produced by Bacillus amyloliquefaciens UFPEDA 485, as well as its long term stability, demonstrate that it has suitable characteristics for human and veterinary applications, and promises to be a powerful drug for the treatment of vascular diseases.

Assessment of the effectiveness of the PPD-mallein produced in Brazil for diagnosing glanders in mules

To assess the potency of the PPD-mallein produced in Brazil, five animals were from a property identified as a focus of glanders. These animals had suggestive clinical signs of the disease and the other five, from a property free from glanders, showed no clinical signs and were serology negative (control group). PPD-mallein from Burkholderia mallei was obtained by precipitation with trichloroacetic acid and ammonium sulfate. The animals were inoculated according to the criteria established by Department of Agriculture, Livestock and Supply (MAPA) for the diagnosis of glanders. After 48 h of application of PPD-mallein, there was swelling in the area of application, presence of ocular secretion and tears in sick animals. The control group showed no inflammatory reaction at the site of inoculation of PPD-mallein. This immunogen produced in Brazil and still being tested was effective for identifying the infection in true positive animals and excluding the truly negative ones, being a new possibility for diagnosis and control of glanders

Taxonomic Approach to Aspergillus sp. Isolated from Caatinga Soil and Potential to Amylase Production

There are several enzymatic productions described in the literature through biotechnological processes with the use of filamentous fungi of the genus Aspergillus (Moreira, 2013; Cunha, 2016). The wide diversity in the characteristics of the enzymes potentiates their application in different processes in the industry, thus, faced with the demand for new amylases with prospect of applicability in the sector, there is a natural stimulus for the exploration of the microbial biodiversity, with the isolation and selection of new strains enzyme producers (Baratto, 2012).