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1.
Rev Biol Trop ; 52(1): 287-95, 2004 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-17357426

RESUMO

The potential role of the fungi, isolated from the peanut rhizosphere, in the production of extracellular and intracellular acid and alkaline phosphatase, was evaluated in vitro. Acid and alkaline extracellular phosphatases showed the highest activities, and the Penicillium species were the most efficient in their production. The correlation analysis showed that extracellular acid and intracellular acid phosphatase produced by Aspergillus niger A. terreus, Penicillium sp. y P. brevicompactum were negatively correlated; while the extracellular and intracellular phosphatase activities, were positively correlated. The extracellular acid phosphatase activities produced in vitro by majority of fungi assayed, were not correlated with the acid phosphatase activity present in the peanut soil rhizosphere. Nevertheless, the extracellular alkaline phosphatase activities produced in vitro, were negatively correlated with the extracellular alkaline phosphatase activities present in the rhizosphere. The ability of phosphatase production by fungi isolated from peanut rhizosphere suggests they have great potential to contribute to the P mineralization in this zone.


Assuntos
Fosfatase Ácida/metabolismo , Fosfatase Alcalina/metabolismo , Arachis/microbiologia , Aspergillus/enzimologia , Penicillium/enzimologia , Arachis/citologia
2.
Rev. biol. trop ; Rev. biol. trop;51(supl. 4): 141-147, jun. 2003. tab
Artigo em Espanhol | LILACS | ID: lil-388925

RESUMO

This research expresses the potential of the bacterial activity present in the organic extracts obtained from Penicillium sp., isolated from the esponge Irciniafelix. This activity was evaluated through agar diffusion test and Minimal Inhibitory Concentration (MIC). The susceptibility trials of organic fractions were carried out against Staphylococcus aureus, S. epidermidis, Bacillus cereus and B. subtilis. The use of the chromatographic techniques (CLV and TLC), permitted to obtain bioactive organic extracts of different polarities, of which only the EtOAc and MeOH fractions inhibited the growth of the bacteria used. Of the EtOAc fractionation, only fraction number 3 EtOAc/Hex presented greatest activity against the Gram-positive bacteria. Number 1 EtOAc/Hex fraction increased its activity against S. aureus (24 mm) and S. epidermidis (25 mm), which can be explained by the loss of possible antagonistic effect during the fractionation process. The CMI trials were carried out for the EtOAc number I subfraction against S. aureus, S. epidermidis, B. cereus and B. subtilis, wich was clinical interest, and shows the potential of this organic extract as antimicrobial agent.


Assuntos
Animais , Antibacterianos , Bactérias Gram-Positivas , Penicillium , Poríferos , Testes de Sensibilidade Microbiana , Penicillium
3.
Rev Biol Trop ; 51 Suppl 4: 141-7, 2003 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-15264564

RESUMO

This research expresses the potential of the bacterial activity present in the organic extracts obtained from Penicillium sp., isolated from the esponge Irciniafelix. This activity was evaluated through agar diffusion test and Minimal Inhibitory Concentration (MIC). The susceptibility trials of organic fractions were carried out against Staphylococcus aureus, S. epidermidis, Bacillus cereus and B. subtilis. The use of the chromatographic techniques (CLV and TLC), permitted to obtain bioactive organic extracts of different polarities, of which only the EtOAc and MeOH fractions inhibited the growth of the bacteria used. Of the EtOAc fractionation, only fraction number 3 EtOAc/Hex presented greatest activity against the Gram-positive bacteria. Number 1 EtOAc/Hex fraction increased its activity against S. aureus (24 mm) and S. epidermidis (25 mm), which can be explained by the loss of possible antagonistic effect during the fractionation process. The CMI trials were carried out for the EtOAc number I subfraction against S. aureus, S. epidermidis, B. cereus and B. subtilis, wich was clinical interest, and shows the potential of this organic extract as antimicrobial agent.


Assuntos
Antibacterianos/farmacologia , Bactérias Gram-Positivas/efeitos dos fármacos , Penicillium/isolamento & purificação , Poríferos/microbiologia , Animais , Testes de Sensibilidade Microbiana , Penicillium/química
4.
Rev. biol. trop ; Rev. biol. trop;48(Supl.1): 199-206, dic. 2000.
Artigo em Espanhol | LILACS | ID: lil-503261

RESUMO

Organic extracts of the sponge Aplysina fistularis (Pallas 1766) were tested for antimicrobial activity against Gram positive bacteria (Staphylococcus aureus) and Gram negative bacteria (Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa). The minimal inhibitory concentration (MIC) and toxic activity of extract were determined. Susceptibility trials of organic fractions obtained by VLC: Hexane, EtOAc and CHCl3 showed that EtOAc fraction has antibacterial activity against E. coli, while CHCl3 fraction inhibited E. coli and S. aureus growth. The later refractioning of EtOAc fraction and the biodirected assays showed that fractions F12 and F13 of EtOAc/Hex and EtOAc F14 were bioactive against Gram positive and Gram negative bacteria. Only EtOAc/MeOH Sf2 from subfractionig of EtOAc F14 produced inhibition for E. coli and S. aureus. In Sf2 EtOAc/MeOH, MIC was moderate for S. aureus (MIC > 256 g/ml). F4 CHCl3/MeOH produced a high inhibition in S. aureus (MIC = 0.125 g/ml) and for E. coli (MIC > 16 g/ml). F10 CHCl3/MeOH showed a moderate activity against S. aureus (MIC > 128 g/ml) and low activity against E. coli (MIC = 512 g/ml). F10 CHCL3/MeOH did no present toxic activity against Artemia salina. The fractiorts F4 CHCL3/MeOH and Sf2 EtOAc/MeOH were toxic for this organism when the concentration was higher than 100 microg/ml. LC50 in both cases was 548.4 and 243.4 microg/ml respectively. Secondary metabolites of medium polarity obtained from A. fistularis have a wide spectrum of anti bacterial activity. Toxicity analysis suggests that only F10 CHCL3/MeOH has potential as an antimicrobial agent for clinical use.


Assuntos
Animais , Antibacterianos/farmacologia , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Poríferos/química , Dose Letal Mediana , Testes de Sensibilidade Microbiana
5.
Rev Biol Trop ; 48 Suppl 1: 199-206, 2000 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-15266809

RESUMO

Organic extracts of the sponge Aplysina fistularis (Pallas 1766) were tested for antimicrobial activity against Gram positive bacteria (Staphylococcus aureus) and Gram negative bacteria (Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa). The minimal inhibitory concentration (MIC) and toxic activity of extract were determined. Susceptibility trials of organic fractions obtained by VLC: Hexane, EtOAc and CHCl3 showed that EtOAc fraction has antibacterial activity against E. coli, while CHCl3 fraction inhibited E. coli and S. aureus growth. The later refractioning of EtOAc fraction and the biodirected assays showed that fractions F12 and F13 of EtOAc/Hex and EtOAc F14 were bioactive against Gram positive and Gram negative bacteria. Only EtOAc/MeOH Sf2 from subfractionig of EtOAc F14 produced inhibition for E. coli and S. aureus. In Sf2 EtOAc/MeOH, MIC was moderate for S. aureus (MIC > 256 g/ml). F4 CHCl3/MeOH produced a high inhibition in S. aureus (MIC = 0.125 g/ml) and for E. coli (MIC > 16 g/ml). F10 CHCl3/MeOH showed a moderate activity against S. aureus (MIC > 128 g/ml) and low activity against E. coli (MIC = 512 g/ml). F10 CHCL3/MeOH did no present toxic activity against Artemia salina. The fractiorts F4 CHCL3/MeOH and Sf2 EtOAc/MeOH were toxic for this organism when the concentration was higher than 100 microg/ml. LC50 in both cases was 548.4 and 243.4 microg/ml respectively. Secondary metabolites of medium polarity obtained from A. fistularis have a wide spectrum of anti bacterial activity. Toxicity analysis suggests that only F10 CHCL3/MeOH has potential as an antimicrobial agent for clinical use.


Assuntos
Antibacterianos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Poríferos/química , Animais , Dose Letal Mediana , Testes de Sensibilidade Microbiana
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