The fungus Aspergillus niger produced extracellular and cellular acid phosphatase activities duri... more The fungus Aspergillus niger produced extracellular and cellular acid phosphatase activities during growth in the presence or absences of copper ions in the medium. The levels of both phosphatase activities depended on the copper concentrations in the medium. Enzyme ...
Copper accumulation and phosphatase activities of three Aspergillus species resistant to copper w... more Copper accumulation and phosphatase activities of three Aspergillus species resistant to copper were compared to three copper-sensitive Rhizopus species. High level of acid phosphatases and decreased Cu2+-uptake were found with resistant in contrast to sensitive strains. The presence of copper(II) ions in the medium increased the production of acid phosphatases in the resistant A. niger and decreased their activity in the sensitive R. delemar. Copper ions inhibited the activity of A. niger cellular acid phosphatase with a Ki of 8.9x10(-4) M and slightly activated the R. delemar enzyme.
The fungus Rhizopus delemar produced extracellular and cellular acid phosphatase during the growt... more The fungus Rhizopus delemar produced extracellular and cellular acid phosphatase during the growth in starch-supplemented medium in the presence or absence of copper ions. The levels of both AP-ase activities were maximal at the end of exponential growth phase and ...
World Journal of Microbiology & Biotechnology, 2003
A rapid qualitative test is proposed for bacterial respiratory type based on 24 h culturing of ba... more A rapid qualitative test is proposed for bacterial respiratory type based on 24 h culturing of bacteria in liquid medium supplemented with a redox indicator: methylene blue or resazurin. Five reference bacterial strains with definite respiratory type as well as nine bacterial isolates from a laboratory digester for methane fermentation were used. Results obtained showed that both indicators can be used for distinction of strict aerobes from other bacterial representatives with definite respiration. In addition, the resazurin is able to differentiate strict anaerobes from microaerophiles and other anaerobes. The main advantages of the methylene blue is that it is a cheap, easily accessible dye, wide-used in microbiological practice and the results obtained with it are more stable over time. It was also noticed that the test with both indicators gave reliable results for the bacterial respiration only when an inoculum up to 48 h old was used.
The fungus Aspergillus niger produced extracellular and cellular acid phosphatase activities duri... more The fungus Aspergillus niger produced extracellular and cellular acid phosphatase activities during growth in the presence or absences of copper ions in the medium. The levels of both phosphatase activities depended on the copper concentrations in the medium. Enzyme ...
Copper accumulation and phosphatase activities of three Aspergillus species resistant to copper w... more Copper accumulation and phosphatase activities of three Aspergillus species resistant to copper were compared to three copper-sensitive Rhizopus species. High level of acid phosphatases and decreased Cu2+-uptake were found with resistant in contrast to sensitive strains. The presence of copper(II) ions in the medium increased the production of acid phosphatases in the resistant A. niger and decreased their activity in the sensitive R. delemar. Copper ions inhibited the activity of A. niger cellular acid phosphatase with a Ki of 8.9x10(-4) M and slightly activated the R. delemar enzyme.
The fungus Rhizopus delemar produced extracellular and cellular acid phosphatase during the growt... more The fungus Rhizopus delemar produced extracellular and cellular acid phosphatase during the growth in starch-supplemented medium in the presence or absence of copper ions. The levels of both AP-ase activities were maximal at the end of exponential growth phase and ...
World Journal of Microbiology & Biotechnology, 2003
A rapid qualitative test is proposed for bacterial respiratory type based on 24 h culturing of ba... more A rapid qualitative test is proposed for bacterial respiratory type based on 24 h culturing of bacteria in liquid medium supplemented with a redox indicator: methylene blue or resazurin. Five reference bacterial strains with definite respiratory type as well as nine bacterial isolates from a laboratory digester for methane fermentation were used. Results obtained showed that both indicators can be used for distinction of strict aerobes from other bacterial representatives with definite respiration. In addition, the resazurin is able to differentiate strict anaerobes from microaerophiles and other anaerobes. The main advantages of the methylene blue is that it is a cheap, easily accessible dye, wide-used in microbiological practice and the results obtained with it are more stable over time. It was also noticed that the test with both indicators gave reliable results for the bacterial respiration only when an inoculum up to 48 h old was used.
Uploads
Papers by Danka Galabova