Whether green nanotechnology can be effectively used with biological control agents in integrated... more Whether green nanotechnology can be effectively used with biological control agents in integrated pest management is currently unknown. We biosynthesized 8–33 nm nanoparticles (NPs) using extracts from the fungus Fusarium solani: silver (AgNPs), selenium (SeNPs), silicon dioxide (SiO2NPs), copper oxide, titanium dioxide (TiO2NPs) and zinc oxide (ZnONPs). They were applied to the adult, egg, and larval stages of Callosobruchus chinensis (Cc) and Callosobruchus maculatus (Cm) directly or via azuki beans Vigna angularis, and the adult stage of their parasitoid wasp Anisopteromalus calandrae. Susceptibility to the nanoparticles was species-dependent and differed among developmental stages; adults and eggs were more susceptible than larvae in the beetles except for Cc adults. Female adult longevity was shortened by SeNPs in A. calandrae and by SeNPs and AgNPs in Cm. In contrast, ZnONPs elongated Cc adult longevity and SeNPs elongated male Cm longevity. When eggs were treated, SeNPs and T...
The present study investigated the biosynthesis of silver (AgNPs), zinc oxide (ZnONPs) and titani... more The present study investigated the biosynthesis of silver (AgNPs), zinc oxide (ZnONPs) and titanium dioxide (TiO2NPs) nanoparticles using Aspergillusoryzae, Aspergillusterreus and Fusariumoxysporum. Nanocomposites (NCs) were successfully synthesized by mixing nanoparticles using a Sonic Vibra-Cell VC/VCX processor. A number of analytical techniques were used to characterize the synthesized biological metal nanoparticles. Several experiments tested biologically synthesized metal nanoparticles and nanocomposites against two types of human pathogenic bacteria, including Gram-positive Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA), and Gram-negative Escherichia coli and Pseudomonasaeruginosa. Additionally, the antitumor activity in HCT-116 cells (colonic carcinoma) was also evaluated. Significant antimicrobial effects of various synthesized forms of nanoparticles and nanocomposites against E. coli and P. aeruginosa bacteria were detected. Various synthesize...
One of the substantial and most ordinary requests asked for that when starting to oversee nanopar... more One of the substantial and most ordinary requests asked for that when starting to oversee nanoparticles is “The reason are nanoparticles so intriguing? Why work with these to an incredible degree little structures that are attempting to manage and join especially when differentiated and their obviously noticeable accomplices? The suitable reaction lies in the novel properties controlled by these nanoparticles. In vitro myco synthesis of silver nanoparticles (AgNPs) using Penicillium aurantiogresium, Penicillium roqueforti, Aspergillus niger, Verticillium chlamydosporium var. chlamydosporium, Trichoderma viride andTrichoderma longibranchiatum had been investigated. The procedure of silver particle lessening by either extracellular contagious filtrate or intracellular without cell filtrate was accomplished which prompt the improvement of an easy procedure for the amalgamation of silver nanoparticles. Upon exposure of the fungal filtrate to silver nitrate, the latter was reduced to sil...
The goal of the current work was to visualize the interaction between silver nanoparticles of 8.9... more The goal of the current work was to visualize the interaction between silver nanoparticles of 8.916.73 nm and some microorganisms as well as to estimate the morphological uniqueness of naturalassemblage of some mycosynthesized silver nanoparticles (AgNPs) with different bacteria and fungi, to ascertain the prospect of the antimicrobial potential of the biosynthesized AgNPs that were systematically evaluated against fourteen pathogenic bacteria and eight fungal isolates included four isolates of yeast like fungi. Remarkably, the AgNPs-antimicrobial activity was evident particularly against highly infectious tested isolates ai eacab fa efib methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa, Klebsiella pneumoniae, Alcaligenes faecalis, Escherichia coli, as well as several fungal pathogens of Candida albicans, C. tropicalis, Trichoderma reesei, Aspergillus niger, and Penicillium marneffei. Moreover, electron microscopy visualizations of the interactions between ...
CHRATOXIN A (OTA) is one of the most significant ……..mycotoxins of worldwide concern f... more CHRATOXIN A (OTA) is one of the most significant ……..mycotoxins of worldwide concern for human health. Various fungi which are ubiquitous contaminants of Egyptian cereals, pre- and post- harvest can produce OTA under ecophysiological conditions. Sixty two fungal isolates belonging to four genera have been isolated from Egyptian cereals. Nine isolates have the ability to produce OTA namely; A. ochraceus, A. terreus, A. fumigatus, A. alliaceus, A. carbonarius, A. niger, A. sclerotioniger, A. versicolor and P. verrucosum. The highest OTA producer strains which isolated from Egyptian rice grains are A. ochraceus, A. terreus and A. fumigatus. A. terreus and A. fumigatus were selected for this study. Both strains show optimum growth rate using Yeast Extract Sucrose (YES) culture medium, incubation temperature at 30oC with 0.98 water activity (aw) after 7 days. Maximum OTA production has been obtained for both strains at 0.98 aw at 25-30 oC after 14 and 21 days in culture medium and rice grains respectively. The two strains failed to grow and to produce OTA at 8oC on YES medium and rice grains at all tested conditions. No OTA was detected at 0.85 aw in culture medium, while the two fungal strains couldn’t grow on rice at the same aw and failed to produce OTA at 0.90 aw at all tested temperature during the 21 days incubation period. Conclusively our results show that the use of different storage practices of water activity (aw) and temperature levels below 0.90 and 20°C, respectively, enhance controlling fungal contamination and minimizing the OTA production in rice grains.
Sequencing of the conserved region of ver-1 gene in each of two Egyptian
Aspergillus sp., A. nidu... more Sequencing of the conserved region of ver-1 gene in each of two Egyptian Aspergillus sp., A. nidulans and A. parasiticus isolates, was conducted. Variation in DNA size (515 bp for A. nidulans and 495 bp for A. parasiticus) was observed with a high homology degree of 97%, however with no difference in the translated amino acid sequence. The obtained ver-1 gene sequence of both isolates was matched, using genebank database, with that of each of a no. of strains belonging to Aspergillus species, protein homology with the most similar strain was then conducted. No difference in the translated amino acids was observed for ver-1 gene of the A. nidulans isolate while two amino acid variations were observed in case of A. parasiticus isolate. The obtained sequences of the two investigated local isolates revealed no matching results with any of the A. nidulans strains on the gene bank database reflecting the uniqueness of the A. nidulans Egyptian isolate
Ubiquinone and protein profiles of twenty nine Penicillium aurantiogriseum type strains were stud... more Ubiquinone and protein profiles of twenty nine Penicillium aurantiogriseum type strains were studied as chemotaxonomic markers. Both markers succeeded in classifying the investigated type strains into three (for ubiquinone) and four (for protein) main groups. The present study provides useful markers for the intraspecific discrimination of the investigated strains and concluded unique in profiling the ubiquinone and protein patterns using HPLC and SDS-PAGE, respectively, of twenty three P. aurantiogriseum type strains
The goal of the current work was to visualize the interaction between silver nanoparticles of 8.9... more The goal of the current work was to visualize the interaction between silver nanoparticles of 8.9- 16.73 nm and some microorganisms as well as to estimate the morphological uniqueness of natural- assemblage of some mycosynthesized silver nanoparticles (AgNPs) with different bacteria and fungi. To ascertain the prospect of the antimicrobial potential of the biosynthesized AgNPs they were systematically evaluated against fourteen pathogenic bacteria and eight fungal isolates included four isolates of yeast like fungi. Remarkably, the AgNPs-antimicrobial activity was evident particularly against highly infectious tested isolates like methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa, Klebsiella pneumoniae, Alcaligenes faecalis, Escherichia coli, as well as several fungal pathogens like Candida albicans, C. tropicalis, Trichoderma reesei, Aspergillus niger, and Penicillium marneffei. Moreover, electron microscopy visualizations of the interactions between AgNPs and tested microorganisms showed that AgNPs were very harmful to some of them causing complete damage to the cells, while it binds compactly to the exterior of some others and/or entered the cell with no observable injures to them, indicating satisfactory natural- assemblage capability. Conclusively, our outcomes showed the way that biosynthesized AgNPs interact with the investigated microorganisms which indicate possibly using the AgNPs as a potent antibacterial and/or antifungal agent against broad spectrum pathogenic bacteria and fungi.
In vitro mycosynthesis of silver nanoparticles (AgNPs) using Penicillium aurantiogresium, Penicil... more In vitro mycosynthesis of silver nanoparticles (AgNPs) using Penicillium aurantiogresium, Penicillium roqueforti, Aspergillus niger, Verticillium chlamydosporium var. chlamydosporium, Trichoderma viride and Trichoderma longibranchiatum had been investigated. The process of silver ion reduction by either extracellular fungal filtrate or intracellular cell-free filtrate was achieved which lead to the development of an easy process for synthesis of silver nanoparticles. Upon exposure of the fungal filtrate to silver nitrate, the latter was reduced to silver nanoparticles as indicated by a color change observed and characterized by UV-visible spectroscopy. The optimum experimental conditions for AgNPs synthesis were found to be a temperature of 37oC at pH of 6.0 and a substrate concentration of 2mM silver nitrate after 24 hours incubation times in dark and measured spectrophotometrically at 430 nm. Silver nanoparticles produced were characterized by various analytical techniques such as TEM, FT-IR and X-Ray analysis of both EDX and XRD. The obtained results revealed that the size of nanoparticles for all the tested fungi ranged from 8.97 to 16.73 nm with variable shapes, most of them present in spherical in nature.
2-The Regional Center for Mycology and Biotechnology (RCMB), Al-Azhar University, Cairo, Egypt.
A... more 2-The Regional Center for Mycology and Biotechnology (RCMB), Al-Azhar University, Cairo, Egypt. ABSTRACT Eleven isolates belonging to Penicillium roqueforti were classified from the analysis of their crude extracts by a polyphasic approach with data processing, using the profiles of their fatty acid; secondary and volatile metabolites as taxonomic markers for these isolates, as well as random amplified polymorphic DNA-polymerase chain reaction pattern (RAPD-PCR) technique for the phylogenetic relationship analysis at the intraspecies level using six universal primers. The study showed that with the harmony of all the four investigated markers, about all of the investigated isolates could be classified correctly at the intraspecific level using only the analysis of metabolites produced on one growth medium (YES), except in case of the volatile profile which succeeded as cladogenetic profile but not as a strain marker. The study revealed the ability of RAPD-PCR technique to evaluate the genetic diversity among the investigated isolates at the sub-species level, as well as a rapid and easy method than traditional characterization techniques. Other relations between isolates could be read from the dendrograms and the efficient classification showed the potential of this polyphasic approach identification system.
Whether green nanotechnology can be effectively used with biological control agents in integrated... more Whether green nanotechnology can be effectively used with biological control agents in integrated pest management is currently unknown. We biosynthesized 8–33 nm nanoparticles (NPs) using extracts from the fungus Fusarium solani: silver (AgNPs), selenium (SeNPs), silicon dioxide (SiO2NPs), copper oxide, titanium dioxide (TiO2NPs) and zinc oxide (ZnONPs). They were applied to the adult, egg, and larval stages of Callosobruchus chinensis (Cc) and Callosobruchus maculatus (Cm) directly or via azuki beans Vigna angularis, and the adult stage of their parasitoid wasp Anisopteromalus calandrae. Susceptibility to the nanoparticles was species-dependent and differed among developmental stages; adults and eggs were more susceptible than larvae in the beetles except for Cc adults. Female adult longevity was shortened by SeNPs in A. calandrae and by SeNPs and AgNPs in Cm. In contrast, ZnONPs elongated Cc adult longevity and SeNPs elongated male Cm longevity. When eggs were treated, SeNPs and T...
The present study investigated the biosynthesis of silver (AgNPs), zinc oxide (ZnONPs) and titani... more The present study investigated the biosynthesis of silver (AgNPs), zinc oxide (ZnONPs) and titanium dioxide (TiO2NPs) nanoparticles using Aspergillusoryzae, Aspergillusterreus and Fusariumoxysporum. Nanocomposites (NCs) were successfully synthesized by mixing nanoparticles using a Sonic Vibra-Cell VC/VCX processor. A number of analytical techniques were used to characterize the synthesized biological metal nanoparticles. Several experiments tested biologically synthesized metal nanoparticles and nanocomposites against two types of human pathogenic bacteria, including Gram-positive Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA), and Gram-negative Escherichia coli and Pseudomonasaeruginosa. Additionally, the antitumor activity in HCT-116 cells (colonic carcinoma) was also evaluated. Significant antimicrobial effects of various synthesized forms of nanoparticles and nanocomposites against E. coli and P. aeruginosa bacteria were detected. Various synthesize...
One of the substantial and most ordinary requests asked for that when starting to oversee nanopar... more One of the substantial and most ordinary requests asked for that when starting to oversee nanoparticles is “The reason are nanoparticles so intriguing? Why work with these to an incredible degree little structures that are attempting to manage and join especially when differentiated and their obviously noticeable accomplices? The suitable reaction lies in the novel properties controlled by these nanoparticles. In vitro myco synthesis of silver nanoparticles (AgNPs) using Penicillium aurantiogresium, Penicillium roqueforti, Aspergillus niger, Verticillium chlamydosporium var. chlamydosporium, Trichoderma viride andTrichoderma longibranchiatum had been investigated. The procedure of silver particle lessening by either extracellular contagious filtrate or intracellular without cell filtrate was accomplished which prompt the improvement of an easy procedure for the amalgamation of silver nanoparticles. Upon exposure of the fungal filtrate to silver nitrate, the latter was reduced to sil...
The goal of the current work was to visualize the interaction between silver nanoparticles of 8.9... more The goal of the current work was to visualize the interaction between silver nanoparticles of 8.916.73 nm and some microorganisms as well as to estimate the morphological uniqueness of naturalassemblage of some mycosynthesized silver nanoparticles (AgNPs) with different bacteria and fungi, to ascertain the prospect of the antimicrobial potential of the biosynthesized AgNPs that were systematically evaluated against fourteen pathogenic bacteria and eight fungal isolates included four isolates of yeast like fungi. Remarkably, the AgNPs-antimicrobial activity was evident particularly against highly infectious tested isolates ai eacab fa efib methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa, Klebsiella pneumoniae, Alcaligenes faecalis, Escherichia coli, as well as several fungal pathogens of Candida albicans, C. tropicalis, Trichoderma reesei, Aspergillus niger, and Penicillium marneffei. Moreover, electron microscopy visualizations of the interactions between ...
CHRATOXIN A (OTA) is one of the most significant ……..mycotoxins of worldwide concern f... more CHRATOXIN A (OTA) is one of the most significant ……..mycotoxins of worldwide concern for human health. Various fungi which are ubiquitous contaminants of Egyptian cereals, pre- and post- harvest can produce OTA under ecophysiological conditions. Sixty two fungal isolates belonging to four genera have been isolated from Egyptian cereals. Nine isolates have the ability to produce OTA namely; A. ochraceus, A. terreus, A. fumigatus, A. alliaceus, A. carbonarius, A. niger, A. sclerotioniger, A. versicolor and P. verrucosum. The highest OTA producer strains which isolated from Egyptian rice grains are A. ochraceus, A. terreus and A. fumigatus. A. terreus and A. fumigatus were selected for this study. Both strains show optimum growth rate using Yeast Extract Sucrose (YES) culture medium, incubation temperature at 30oC with 0.98 water activity (aw) after 7 days. Maximum OTA production has been obtained for both strains at 0.98 aw at 25-30 oC after 14 and 21 days in culture medium and rice grains respectively. The two strains failed to grow and to produce OTA at 8oC on YES medium and rice grains at all tested conditions. No OTA was detected at 0.85 aw in culture medium, while the two fungal strains couldn’t grow on rice at the same aw and failed to produce OTA at 0.90 aw at all tested temperature during the 21 days incubation period. Conclusively our results show that the use of different storage practices of water activity (aw) and temperature levels below 0.90 and 20°C, respectively, enhance controlling fungal contamination and minimizing the OTA production in rice grains.
Sequencing of the conserved region of ver-1 gene in each of two Egyptian
Aspergillus sp., A. nidu... more Sequencing of the conserved region of ver-1 gene in each of two Egyptian Aspergillus sp., A. nidulans and A. parasiticus isolates, was conducted. Variation in DNA size (515 bp for A. nidulans and 495 bp for A. parasiticus) was observed with a high homology degree of 97%, however with no difference in the translated amino acid sequence. The obtained ver-1 gene sequence of both isolates was matched, using genebank database, with that of each of a no. of strains belonging to Aspergillus species, protein homology with the most similar strain was then conducted. No difference in the translated amino acids was observed for ver-1 gene of the A. nidulans isolate while two amino acid variations were observed in case of A. parasiticus isolate. The obtained sequences of the two investigated local isolates revealed no matching results with any of the A. nidulans strains on the gene bank database reflecting the uniqueness of the A. nidulans Egyptian isolate
Ubiquinone and protein profiles of twenty nine Penicillium aurantiogriseum type strains were stud... more Ubiquinone and protein profiles of twenty nine Penicillium aurantiogriseum type strains were studied as chemotaxonomic markers. Both markers succeeded in classifying the investigated type strains into three (for ubiquinone) and four (for protein) main groups. The present study provides useful markers for the intraspecific discrimination of the investigated strains and concluded unique in profiling the ubiquinone and protein patterns using HPLC and SDS-PAGE, respectively, of twenty three P. aurantiogriseum type strains
The goal of the current work was to visualize the interaction between silver nanoparticles of 8.9... more The goal of the current work was to visualize the interaction between silver nanoparticles of 8.9- 16.73 nm and some microorganisms as well as to estimate the morphological uniqueness of natural- assemblage of some mycosynthesized silver nanoparticles (AgNPs) with different bacteria and fungi. To ascertain the prospect of the antimicrobial potential of the biosynthesized AgNPs they were systematically evaluated against fourteen pathogenic bacteria and eight fungal isolates included four isolates of yeast like fungi. Remarkably, the AgNPs-antimicrobial activity was evident particularly against highly infectious tested isolates like methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa, Klebsiella pneumoniae, Alcaligenes faecalis, Escherichia coli, as well as several fungal pathogens like Candida albicans, C. tropicalis, Trichoderma reesei, Aspergillus niger, and Penicillium marneffei. Moreover, electron microscopy visualizations of the interactions between AgNPs and tested microorganisms showed that AgNPs were very harmful to some of them causing complete damage to the cells, while it binds compactly to the exterior of some others and/or entered the cell with no observable injures to them, indicating satisfactory natural- assemblage capability. Conclusively, our outcomes showed the way that biosynthesized AgNPs interact with the investigated microorganisms which indicate possibly using the AgNPs as a potent antibacterial and/or antifungal agent against broad spectrum pathogenic bacteria and fungi.
In vitro mycosynthesis of silver nanoparticles (AgNPs) using Penicillium aurantiogresium, Penicil... more In vitro mycosynthesis of silver nanoparticles (AgNPs) using Penicillium aurantiogresium, Penicillium roqueforti, Aspergillus niger, Verticillium chlamydosporium var. chlamydosporium, Trichoderma viride and Trichoderma longibranchiatum had been investigated. The process of silver ion reduction by either extracellular fungal filtrate or intracellular cell-free filtrate was achieved which lead to the development of an easy process for synthesis of silver nanoparticles. Upon exposure of the fungal filtrate to silver nitrate, the latter was reduced to silver nanoparticles as indicated by a color change observed and characterized by UV-visible spectroscopy. The optimum experimental conditions for AgNPs synthesis were found to be a temperature of 37oC at pH of 6.0 and a substrate concentration of 2mM silver nitrate after 24 hours incubation times in dark and measured spectrophotometrically at 430 nm. Silver nanoparticles produced were characterized by various analytical techniques such as TEM, FT-IR and X-Ray analysis of both EDX and XRD. The obtained results revealed that the size of nanoparticles for all the tested fungi ranged from 8.97 to 16.73 nm with variable shapes, most of them present in spherical in nature.
2-The Regional Center for Mycology and Biotechnology (RCMB), Al-Azhar University, Cairo, Egypt.
A... more 2-The Regional Center for Mycology and Biotechnology (RCMB), Al-Azhar University, Cairo, Egypt. ABSTRACT Eleven isolates belonging to Penicillium roqueforti were classified from the analysis of their crude extracts by a polyphasic approach with data processing, using the profiles of their fatty acid; secondary and volatile metabolites as taxonomic markers for these isolates, as well as random amplified polymorphic DNA-polymerase chain reaction pattern (RAPD-PCR) technique for the phylogenetic relationship analysis at the intraspecies level using six universal primers. The study showed that with the harmony of all the four investigated markers, about all of the investigated isolates could be classified correctly at the intraspecific level using only the analysis of metabolites produced on one growth medium (YES), except in case of the volatile profile which succeeded as cladogenetic profile but not as a strain marker. The study revealed the ability of RAPD-PCR technique to evaluate the genetic diversity among the investigated isolates at the sub-species level, as well as a rapid and easy method than traditional characterization techniques. Other relations between isolates could be read from the dendrograms and the efficient classification showed the potential of this polyphasic approach identification system.
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Papers by Eman Helmy
Aspergillus sp., A. nidulans and A. parasiticus isolates, was conducted. Variation in
DNA size (515 bp for A. nidulans and 495 bp for A. parasiticus) was observed with a high
homology degree of 97%, however with no difference in the translated amino acid sequence.
The obtained ver-1 gene sequence of both isolates was matched, using genebank database,
with that of each of a no. of strains belonging to Aspergillus species, protein homology
with the most similar strain was then conducted. No difference in the translated amino
acids was observed for ver-1 gene of the A. nidulans isolate while two amino acid
variations were observed in case of A. parasiticus isolate. The obtained sequences of the
two investigated local isolates revealed no matching results with any of the A. nidulans
strains on the gene bank database reflecting the uniqueness of the A. nidulans Egyptian
isolate
ABSTRACT
Eleven isolates belonging to Penicillium roqueforti were classified from the analysis of their crude extracts by a polyphasic approach with data processing, using the profiles of their fatty acid; secondary and volatile metabolites as taxonomic markers for these isolates, as well as random amplified polymorphic DNA-polymerase chain reaction pattern (RAPD-PCR) technique for the phylogenetic relationship analysis at the intraspecies level using six universal primers. The study showed that with the harmony of all the four investigated markers, about all of the investigated isolates could be classified correctly at the intraspecific level using only the analysis of metabolites produced on one growth medium (YES), except in case of the volatile profile which succeeded as cladogenetic profile but not as a strain marker. The study revealed the ability of RAPD-PCR technique to evaluate the genetic diversity among the investigated isolates at the sub-species level, as well as a rapid and easy method than traditional characterization techniques. Other relations between isolates could be read from the dendrograms and the efficient classification showed the potential of this polyphasic approach identification system.
Aspergillus sp., A. nidulans and A. parasiticus isolates, was conducted. Variation in
DNA size (515 bp for A. nidulans and 495 bp for A. parasiticus) was observed with a high
homology degree of 97%, however with no difference in the translated amino acid sequence.
The obtained ver-1 gene sequence of both isolates was matched, using genebank database,
with that of each of a no. of strains belonging to Aspergillus species, protein homology
with the most similar strain was then conducted. No difference in the translated amino
acids was observed for ver-1 gene of the A. nidulans isolate while two amino acid
variations were observed in case of A. parasiticus isolate. The obtained sequences of the
two investigated local isolates revealed no matching results with any of the A. nidulans
strains on the gene bank database reflecting the uniqueness of the A. nidulans Egyptian
isolate
ABSTRACT
Eleven isolates belonging to Penicillium roqueforti were classified from the analysis of their crude extracts by a polyphasic approach with data processing, using the profiles of their fatty acid; secondary and volatile metabolites as taxonomic markers for these isolates, as well as random amplified polymorphic DNA-polymerase chain reaction pattern (RAPD-PCR) technique for the phylogenetic relationship analysis at the intraspecies level using six universal primers. The study showed that with the harmony of all the four investigated markers, about all of the investigated isolates could be classified correctly at the intraspecific level using only the analysis of metabolites produced on one growth medium (YES), except in case of the volatile profile which succeeded as cladogenetic profile but not as a strain marker. The study revealed the ability of RAPD-PCR technique to evaluate the genetic diversity among the investigated isolates at the sub-species level, as well as a rapid and easy method than traditional characterization techniques. Other relations between isolates could be read from the dendrograms and the efficient classification showed the potential of this polyphasic approach identification system.