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Naresh Magan - One of the best experts on this subject based on the ideXlab platform.
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dynamics of solute matric stress interactions with climate change abiotic factors on growth gene expression and ochratoxin a production by Penicillium verrucosum on a wheat based matrix
Fungal Biology, 2021Co-Authors: Shaimaa Abdelmohsen, Carol Verheeckevaessen, Esther Garciacela, Angel Medina, Naresh MaganAbstract:Abstract Penicillium verrucosum contaminates temperate cereals with ochratoxin A (OTA) during harvesting and storage. We examined the effect of temperature (25 vs 30 oC), CO2 (400 vs 1000 ppm) and matric/solute stress (-2.8 vs -7.0 MPa) on (i) growth, (ii) key OTA biosynthetic genes and (iii) OTA production on a milled wheat substrate. Growth was generally faster under matric than solute stress at 25 oC, regardless of CO2 concentrations. At 30 oC, growth of P. verrucosum was significantly reduced under solute stress in both CO2 treatments, with no growth observed at -2.8 MPa (=0.98 water activity, aw) and 1000 ppm CO2. Overall, growth patterns under solute stress was slower in elevated CO2 than under matric stress when compared with existing conditions. The otapksPV gene expression was increased under elevated CO2 levels in matric stress treatments. There was fewer effects on the otanrpsPV biosynthetic gene. This pattern was paralleled with the production of OTA under these conditions. This suggest that P. verrucosum is able to actively grow and survive in both soil and on crop debris under three way interacting climate-related abiotic factors. This resilience suggests that they would still be able to pose an OTA contamination risk in temperate cereals post-harvest.
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Dynamics of solute/matric stress interactions with climate change abiotic factors on growth, gene expression and ochratoxin A production by Penicillium verrucosum on a wheat-based matrix.
Fungal biology, 2020Co-Authors: Shaimaa Abdelmohsen, Angel Medina, Carol Verheecke-vaessen, Esther Garcia-cela, Naresh MaganAbstract:Abstract Penicillium verrucosum contaminates temperate cereals with ochratoxin A (OTA) during harvesting and storage. We examined the effect of temperature (25 vs 30 oC), CO2 (400 vs 1000 ppm) and matric/solute stress (-2.8 vs -7.0 MPa) on (i) growth, (ii) key OTA biosynthetic genes and (iii) OTA production on a milled wheat substrate. Growth was generally faster under matric than solute stress at 25 oC, regardless of CO2 concentrations. At 30 oC, growth of P. verrucosum was significantly reduced under solute stress in both CO2 treatments, with no growth observed at -2.8 MPa (=0.98 water activity, aw) and 1000 ppm CO2. Overall, growth patterns under solute stress was slower in elevated CO2 than under matric stress when compared with existing conditions. The otapksPV gene expression was increased under elevated CO2 levels in matric stress treatments. There was fewer effects on the otanrpsPV biosynthetic gene. This pattern was paralleled with the production of OTA under these conditions. This suggest that P. verrucosum is able to actively grow and survive in both soil and on crop debris under three way interacting climate-related abiotic factors. This resilience suggests that they would still be able to pose an OTA contamination risk in temperate cereals post-harvest.
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solute and matric potential stress on Penicillium verrucosum impact on growth gene expression and ochratoxin a production
World Mycotoxin Journal, 2020Co-Authors: Shaimaa Abdelmohsen, Carol Verheeckevaessen, Esther Garciacela, Angel Medina, Naresh MaganAbstract:Penicillium verrucosum survives in soil and on cereal debris. It colonises grain during harvesting, drying and storage. There is no information on the relative tolerance of P. verrucosum to solute ...
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Environmental factors affect efficacy of some essential oils and resveratrol to control growth and ochratoxin A production by Penicillium verrucosum and Aspergillus westerdijkiae on wheat grain.
Journal of Stored Products Research, 2008Co-Authors: David Aldred, Victoria Cairns-fuller, Naresh MaganAbstract:Abstract This study determined the efficacy of three essential oils (bay, clove and cinnamon oil) and the antioxidant resveratrol (0–500 μg g−1) on the control of growth and ochratoxin A (OTA) production by Penicillium verrucosum and Aspergillus westerdijkiae (=A. ochraceus) under different water activity (aw, 0.90, 0.95, 0.995), and temperature (15, 25 °C) conditions on irradiated wheat grain. The most effective treatment (resveratrol) was then tested on natural grain. The ED50 values for growth inhibition by the oils were 200–300 μg g−1 at the aw and the temperatures tested. For resveratrol, this varied from 350 at 0.995aw at both temperatures. The ED50 values for the control of OTA were slightly lower than for control of growth, with approx. 200 μg g−1 required for the oils and 50–100 μg g−1 of the antioxidant, at 0.90/0.95aw and both temperatures. In wet grain (0.995aw), higher concentrations were required. For growth there were statistically significant effects of single-, two- and three-way interactions between treatments except for concentration×temperature and concentration×temperature×essential oil/antioxidant treatment. For OTA control, statistically significant treatments were aw, temperature×aw, concentration×temperature, treatment×concentration, and three-way interaction of concentration×aw×treatment for P. verrucosum and A. westerdijkiae. Subsequent studies were done with the best treatment (resveratrol, 200 μg g−1) on natural wheat grain with either P. verrucosum or A. westerdijkiae at 0.85–0.995aw and 15/25 °C over 28 days storage. This showed that the populations of the mycotoxigenic species and OTA contamination could be reduced by >60% by this treatment at the end of the storage period.
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physiological relationship between food preservatives environmental factors ochratoxin and otapkspv gene expression by Penicillium verrucosum
International Journal of Food Microbiology, 2007Co-Authors: Markus Schmidtheydt, Rolf Geisen, Esther S Baxter, Naresh MaganAbstract:Abstract There is significant interest in trying to understand the relationship between environmental factors, preservative concentration and expression of genes involved in mycotoxin production. However, little information is available on the link between physiological stress factors and expression of genes responsible for mycotoxin production. This study has examined the effect of interactions between ionic and non-ionic water availability modified with glycerol or NaCl (aw, 0.98, 0.95 and 0.93) and sub-optimal concentrations of calcium propionate and potassium sorbate (150, 300 ppm) at 25 °C on growth, ochratoxin A (OTA) and otapksPV gene expression by the mycotoxigenic species Penicillium verrucosum. Growth was inhibited between 25–35% by the preservatives at each aw level. However, OTA production was stimulated by 150 and 300 ppm of both preservatives, especially at 0.95 and 0.93 aw. If water activity as a single stress factor was changed, a typical OTA production and otapksPV expression profile occurred, indicating that OTA biosynthesis is activated under two conditions, i.e., under optimal growth conditions and under weak stress conditions. Temporal analysis of otapksPV expression showed that there was an optimum after 8–9 days incubation. Statistical analyses indicated good correlation between sub-optimal concentrations of preservatives, intermediate aw levels and genotypic and phenotypic gene and toxin production. This is the first time that genotypic information has been linked to phenotypic mycotoxin production in relation to such interacting stress factors.
Jens Christian Frisvad - One of the best experts on this subject based on the ideXlab platform.
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comments on mycobiota and mycotoxins in traditional medicinal seeds from china toxins 2015 7 3858 3875 in attributing ochratoxin a biosynthesis within the genus Penicillium occurring on natural agricultural produce
Toxins, 2016Co-Authors: Peter G Mantle, Marina Venturini Copetti, Alan G Buddie, Jens Christian FrisvadAbstract:The unusual attribution of trace amounts of ochratoxin A in some Chinese food commodities to Penicillium polonicum is questioned by European experience in searches for ochratoxinogenic food-spoilage Penicillia, where mistaken attribution is now known to have been due to cryptic Penicillium verrucosum contamination. Consequently, selection of single-spore isolates is recommended as pre-requisite for attributing mycotoxin biosynthetic potential to fungi.
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Comments on “Mycobiota and Mycotoxins in Traditional Medicinal Seeds from China. Toxins 2015, 7, 3858-3875”— in Attributing Ochratoxin A Biosynthesis Within the Genus Penicillium Occurring on Natural Agricultural Produce
Toxins, 2016Co-Authors: Peter G Mantle, Marina Venturini Copetti, Alan G Buddie, Jens Christian FrisvadAbstract:The unusual attribution of trace amounts of ochratoxin A in some Chinese food commodities to Penicillium polonicum is questioned by European experience in searches for ochratoxinogenic food-spoilage Penicillia, where mistaken attribution is now known to have been due to cryptic Penicillium verrucosum contamination. Consequently, selection of single-spore isolates is recommended as pre-requisite for attributing mycotoxin biosynthetic potential to fungi.
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Ochratoxin A producing Penicillium verrucosum isolates from cereals reveal large AFLP fingerprinting variability.
Journal of applied microbiology, 2005Co-Authors: Jens Christian Frisvad, Flemming Lund, Susanne ElmholtAbstract:Aims: To examine if molecular amplified fragment length polymorphism (AFLP) fingerprinting of the only ochratoxin A-producing species in European cereals, Penicillium verrucosum, can be used as a method in hazard analysis using critical control points (HACCP). Methods and Results: A total of 321 isolates of P. verrucosum were isolated from ochratoxin A-contaminated cereals from Denmark (oats), UK (wheat and barley) and Sweden (wheat). Of these, 236 produced ochratoxin A as determined by thin layer chromatography; 185 ochratoxin A-producing isolates were selected for AFLP fingerprinting. A total of 138 isolates had unique AFLP patterns, whereas 52 isolates could be allocated to small groups containing from two to four isolates with similar AFLP patterns. A total of 155 clones were found among the 185 P. verrucosum isolates, thus 84% of the isolates may represent different genets of P. verrucosum. As the few isolates that were grouped often came from the same farm, and those groups that contained AFLP-identical isolates from different countries were morphotypically different. On single farms up to 35 clones were found. The few groups of ramets from the same genet indicated that a HACCP approach based on clones may require a very large number of AFLP analysis to work in practice, we recommend basing the HACCP approach on the actual species P. verrucosum. A more detailed characterization should rather be based on the profile of species present at different control points, or analysis of the mycotoxins ochratoxin A and citrinin in the isolates. Examination of 86 isolates with HPLC and diode array detection of P. verrucosum showed that 66% produced ochratoxin A, 87% produced citrinin, 92% produced verrucin and 100% produced verrucolone. Conclusions: Among 184 ochratoxin A-producing Penicillium verrucosum, 155 clonal lineages were indicated by AFLP fingerprinting, indicating a high genetical diversity, yet the species P. verrucosum is phenotypically distinct and valid. Significance and Impact of the Study: AFLP fingerprinting of Penicillium verrucosum indicates that genetic recombination takes place in this fungus.
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Penicillium verrucosum in wheat and barley indicates presence of ochratoxin a
Journal of Applied Microbiology, 2003Co-Authors: Flemming Lund, Jens Christian FrisvadAbstract:Aims: The aims of this study were to isolate and identify ochratoxin A (OTA) producing fungi in cereals containing OTA and to determine the best selective and indicative medium for recovery of OTA producing fungi. Methods and Results: Seventy-six wheat, barley and rye samples from Europe containing OTA and 17 samples without OTA were investigated using three different media, dichloran yeast sucrose agar (DYSG), dichloran rose bengal yeast extract sucrose agar (DRYES) and dichloran 18% glycerol agar (DG18). Hundred kernels were plated on each medium and the kind and number of fungal OTA producers were recorded as percentage of infestation. Penicillium verrucosum was the sole OTA producer found in cereals. The average percentage of infestation of P. verrucosum counts was recorded as 28·3% on DYSG, 10·3% on DRYES and 9·9% on DG18 on the OTA containing samples and 0·8% on DYSG, 0·4% on DRYES and 0·6% on DG18 for the samples without OTA. Conclusions:Penicillium verrucosum was the sole OTA producer in European cereals. Determination of P. verrucosum infestation and infection was best detected on DYSG after 7 days at 20°C. The percentage of infestation of P. verrucosum found on DYSG and OTA content in cereals were correlated. More than 7% infestation of P. verrucosum indicated OTA contamination. Significance and Impact of the Study: The developed method could be used as a cereal quality control.
Rolf Geisen - One of the best experts on this subject based on the ideXlab platform.
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Sequencing and Analysis of the Genome of the Filamentous Fungus Penicillium verrucosum BFE808, Which Produces the Mycotoxins Citrinin and Ochratoxin
Microbiology resource announcements, 2018Co-Authors: Markus Schmidt-heydt, Dominic A. Stoll, Rolf GeisenAbstract:ABSTRACT Penicillium verrucosum is a filamentous ascomycete that occurs worldwide. Various cereals and the products thereof are the main habitats of this fungal species, where it produces the mycotoxins ochratoxin and citrinin. Here, we report the first draft genome sequence of P. verrucosum strain BFE808, isolated from wheat kernels.
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Influence of Different Nanomaterials on Growth and Mycotoxin Production of Penicillium verrucosum
PloS one, 2016Co-Authors: Kathrin Kotzybik, Volker Gräf, Lena Kugler, Dominic A. Stoll, Ralf Greiner, Rolf Geisen, Markus Schmidt-heydtAbstract:Nanoparticles are ubiquitous in the environment. They originate from anthropogenic or natural sources or they are intentionally produced for different purposes. There exist manifold applications of nanoparticles in modern life leading unavoidably to a confrontation and interaction between nanomaterial and living organisms. Based on their wide distribution tending to increase steadily, the influence of particles based on silica and silver, exhibiting nominal sizes between 0.65 nm and 200 nm, on the physiology of the mycotoxigenic filamentous fungus Penicillium verrucosum was analyzed. The applied concentration and time-point, the size and the chemical composition of the particles was shown to have a strong influence on growth and mycotoxin biosynthesis. On microscopic scale it could be shown that silver nanoparticles attach to the mycelial surface. Moreover, silver nanoparticles with 0.65 nm and 5 nm in size were shown to internalize within the cell, form agglomerates in the cytoplasm and associate to cell organelles.
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Growth morphology of Penicillium verrucosum supplemented by NanoComposix silver nanospheres.
2016Co-Authors: Kathrin Kotzybik, Volker Gräf, Lena Kugler, Dominic A. Stoll, Ralf Greiner, Rolf Geisen, Markus Schmidt-heydtAbstract:(a) Growth of Penicillium verrucosum 7 days at 25°C under rotation of 230 rpm in MEA-liquid medium supplemented by different amounts (0–100 ppm) of NanoComposix silver nanospheres exhibiting sizes of 5 nm, 50 nm and 200 nm. Silver has been applied before (!) growth of P. verrucosum (b). Growth of Penicillium verrucosum 7 days at 25°C under rotation of 230 rpm in MEA-liquid medium either as control or supplemented by different amounts (0–100 ppm) of NanoComposix silver nanospheres exhibiting a size of 200 nm. Silver has been applied after (!) growth of P. verrucosum.
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Relative growth density reflecting the growth rates of Penicillium verrucosum supplemented by NanoComposix SiO2 nanospheres.
2016Co-Authors: Kathrin Kotzybik, Volker Gräf, Lena Kugler, Dominic A. Stoll, Ralf Greiner, Rolf Geisen, Markus Schmidt-heydtAbstract:Penicillium verrucosum incubated 7 days at 25°C under shaking of 230 rpm in MEA-liquid medium, supplemented by different amounts (0–2,500 ppm) of NanoComposix SiO2 nanospheres exhibiting sizes of 20 nm, 50 nm, 100 nm and 200 nm. Significant differences (P < 0.05) are indicated with an asterisk. The growth rate is specified as relative growth density. Data in S2 data set.
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Oxidative stress induces the biosynthesis of citrinin by Penicillium verrucosum at the expense of ochratoxin
International Journal of Food Microbiology, 2015Co-Authors: Markus Schmidt-heydt, Dominic A. Stoll, Peter Schütz, Rolf GeisenAbstract:Abstract Penicillium verrucosum is a fungus that can produce ochratoxin A and citrinin, two structurally related nephrotoxic mycotoxins. P. verrucosum usually occurs on wheat but can occasionally also be found in NaCl rich habitats such as salted cheeses or olives, indicating that this fungus can adapt to different environments. The ratio of ochratoxin A to citrinin produced by P. verrucosum is shifted to one of either mycotoxin at the expense of the other dependent on the environmental conditions. High NaCl concentrations shift secondary metabolite biosynthesis towards ochratoxin A production. P. verrucosum copes with NaCl stress by increased ochratoxin A biosynthesis, ensuring chloride homeostasis. Ochratoxin A carries chlorine in its molecule and can excrete chlorine from the cell. It was further shown that the regulation of ochratoxin A by high NaCl conditions is mediated by the HOG MAP kinase signal transduction pathway. Here it is shown that high oxidative stress conditions, evoked for example by increasing concentrations of Cu2 + cations in the growth medium, shift secondary metabolite biosynthesis of P. verrucosum from ochratoxin A to citrinin. The production of citrinin normalizes the oxidative status of the fungal cell under oxidative stress conditions leading to an adaptation to these environmental conditions and protects against increased oxidative stress caused by increased Cu2 + concentrations. Moreover citrinin also protects against light of short wavelength, which may also increase the oxidative status of the environment. The biosynthesis of citrinin is apparently regulated by a cAMP/PKA signaling pathway, because increasing amounts of external cAMP reduce citrinin biosynthesis in a concentration dependent manner. These conditions lead to the cross-regulation of the ochratoxin A/citrinin secondary metabolite pair and support the adaptation of P. verrucosum to different environments.
Débora De Oliveira - One of the best experts on this subject based on the ideXlab platform.
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Production of multifunctional lipases by Penicillium verrucosum and Penicillium brevicompactum under solid state fermentation of babassu cake and castor meal
Bioprocess and Biosystems Engineering, 2011Co-Authors: Marceli Fernandes Silva, Marco Di Luccio, Helen Treichel, Denise M.g. Freire, Aline Machado Castro, Marcio A. Mazutti, J. Vladimir Oliveira, Débora De OliveiraAbstract:The main objective of this work was to optimize lipase production, in terms of hydrolytic and esterification activities, by Penicillium brevicompactum and Penicillium verrucosum in solid state fermentation using agroindustrial residues as raw material. Maxima hydrolytic activities of 48.6 and 87.7 U/g were achieved when P. brevicompactum was cultured in babassu cake and castor meal, respectively. Higher esterification activities (around 244 U/g) were achieved when P. brevicompactum was used as microorganism and babassu cake as raw material. Different experimental conditions led to these promising values, clearly showing that no correlation can be attributed between hydrolytic and esterification activities. In spite of the several applications of lipases which are capable of catalyze synthesis reactions, only few works in this subject are presented in the literature, especially when low cost raw materials are used.
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Imobilização de lipases produzidas por fermentação em estado sólido utilizando Penicillium verrucosum em suportes hidrofóbicos
Ciência e Tecnologia de Alimentos, 2009Co-Authors: Silvana Menoncin, Natalia Molossi Domingues, Jose Vladimir De Oliveira, Marco Di Luccio, Helen Treichel, Denise M.g. Freire, Débora De OliveiraAbstract:The major interest in the immobilization of enzymes is obtaining a biocatalyst with activity and stability that are not affected during the process when compared to the free enzyme. The application of lipases in industries requires the study of techniques suitable for reuse and stability increase such as immobilization strategies. This work studied the immobilization of lipases produced by solid state fermentation from Penicillium verrucosum using two hydrophobic supports: Accurel EP 1000 and activated carbon. For the lipase immobilization, 1 g of support was added to 50 mL of an enzyme solution and kept for 2 hour in an ice bath. The solution was then filtered and the immobilized enzyme was stored in a dissecator for 48 hour before the assays for lipase activity, protein, and specific lipase activity. The results showed that the lipase immobilized in activated carbon presented higher specific activity than the lipase immobilized in Accurel EP 1000. The use of activated carbon as support led to a specific activity of 1.5 × 106 U/mg of protein, yield of 30.42%, and retention of 382.516%.
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Response surface method to optimize the production and characterization of lipase from Penicillium verrucosum in solid-state fermentation
Bioprocess and Biosystems Engineering, 2008Co-Authors: Aniela Pinto Kempka, Silvana Menoncin, Helen Treichel, Denise M.g. Freire, Nadia Lamb Lipke, Thais Luz Fontoura Pinheiro, Marco Di Luccio, Débora De OliveiraAbstract:Current studies about lipase production by solid-state fermentation involve the use of agro-industrial residues towards developing cost-effective systems directed to large-scale commercialization of enzyme-catalyzed processes. In this work, lipase production and partial characterization of the crude enzymatic extracts obtained by Penicillium verrucosum using soybean bran as substrate was investigated. Different inductors were evaluated and the results showed that there is no influence of this variable on the lipase production, while temperature and initial moisture were the main factors that affected enzyme production. The optimized cultivation temperature (27.5 °C) and initial moisture of substrate (55%) were determined using the response surface methodology. Kinetics of lipase production was followed at the optimized growth conditions. Optimum lipase yield was 40 U/g of dry bran. The crude enzymatic extract showed optimal activity in the range from 30 to 45 °C and in pH 7.0.
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Production and partial characterization of lipase from Penicillium verrucosum obtained by submerged fermentation of conventional and industrial media
Ciência e Tecnologia de Alimentos, 2008Co-Authors: Thais Luz Fontoura Pinheiro, Silvana Menoncin, Natalia Molossi Domingues, Marco Di Luccio, Helen Treichel, Débora De Oliveira, Denise M.g. FreireAbstract:The growing interest in lipase production is related to the potential biotechnological applications that these enzymes present. Current studies on lipase production by submerged fermentation involve the use of agro-industrial residues aiming at increasing economic attractiveness. Based on these aspects, the objective of this work was to investigate lipase production by Penicillium verrucosum in submerged fermentation using a conventional medium based on peptone, yeast extract, NaCl and olive oil, and an industrial medium based on corn steep liquor, Prodex Lac (yeast hydrolysate), NaCl and olive oil, as well as to characterize the crude enzymatic extracts obtained. Kinetics of lipase production was evaluated and the highest enzymatic activities, of 3.15 and 2.22 U.mL-1, were observed when conventional and industrial media were used, respectively. The enzymatic extract showed optimal activity in the range from 30 to 40 °C and at pH 7.0. Although the industrial medium presents economical advantages over the conventional medium, the presence of agro-industrial residues rich in nitrogen and other important nutrients seemed to contribute to a reduction in lipase activity.
Markus Schmidt-heydt - One of the best experts on this subject based on the ideXlab platform.
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Sequencing and Analysis of the Genome of the Filamentous Fungus Penicillium verrucosum BFE808, Which Produces the Mycotoxins Citrinin and Ochratoxin
Microbiology resource announcements, 2018Co-Authors: Markus Schmidt-heydt, Dominic A. Stoll, Rolf GeisenAbstract:ABSTRACT Penicillium verrucosum is a filamentous ascomycete that occurs worldwide. Various cereals and the products thereof are the main habitats of this fungal species, where it produces the mycotoxins ochratoxin and citrinin. Here, we report the first draft genome sequence of P. verrucosum strain BFE808, isolated from wheat kernels.
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Comprehensive Proteomic Analysis of Penicillium verrucosum
Proteomics, 2017Co-Authors: Katharina Nöbauer, Markus Schmidt-heydt, Karin Hummel, Corina Mayrhofer, Maike Ahrens, F. M. C. S. Setyabudi, Martin Eisenacher, Ebrahim Razzazi-fazeliAbstract:Mass spectrometric identification of proteins in species lacking validated sequence information is a major problem in veterinary science. In the present study, we used ochratoxin A producing Penicillium verrucosum to identify and quantitatively analyze proteins of an organism with yet no protein information available. The work presented here aimed to provide a comprehensive protein identification of P. verrucosum using shotgun proteomics. We were able to identify 3631 proteins in an "ab initio" translated database from DNA sequences of P. verrucosum. Additionally, a sequential window acquisition of all theoretical fragment-ion spectra analysis was done to find differentially regulated proteins at two different time points of the growth curve. We compared the proteins at the beginning (day 3) and at the end of the log phase (day 12).
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Influence of Different Nanomaterials on Growth and Mycotoxin Production of Penicillium verrucosum
PloS one, 2016Co-Authors: Kathrin Kotzybik, Volker Gräf, Lena Kugler, Dominic A. Stoll, Ralf Greiner, Rolf Geisen, Markus Schmidt-heydtAbstract:Nanoparticles are ubiquitous in the environment. They originate from anthropogenic or natural sources or they are intentionally produced for different purposes. There exist manifold applications of nanoparticles in modern life leading unavoidably to a confrontation and interaction between nanomaterial and living organisms. Based on their wide distribution tending to increase steadily, the influence of particles based on silica and silver, exhibiting nominal sizes between 0.65 nm and 200 nm, on the physiology of the mycotoxigenic filamentous fungus Penicillium verrucosum was analyzed. The applied concentration and time-point, the size and the chemical composition of the particles was shown to have a strong influence on growth and mycotoxin biosynthesis. On microscopic scale it could be shown that silver nanoparticles attach to the mycelial surface. Moreover, silver nanoparticles with 0.65 nm and 5 nm in size were shown to internalize within the cell, form agglomerates in the cytoplasm and associate to cell organelles.
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Growth morphology of Penicillium verrucosum supplemented by NanoComposix silver nanospheres.
2016Co-Authors: Kathrin Kotzybik, Volker Gräf, Lena Kugler, Dominic A. Stoll, Ralf Greiner, Rolf Geisen, Markus Schmidt-heydtAbstract:(a) Growth of Penicillium verrucosum 7 days at 25°C under rotation of 230 rpm in MEA-liquid medium supplemented by different amounts (0–100 ppm) of NanoComposix silver nanospheres exhibiting sizes of 5 nm, 50 nm and 200 nm. Silver has been applied before (!) growth of P. verrucosum (b). Growth of Penicillium verrucosum 7 days at 25°C under rotation of 230 rpm in MEA-liquid medium either as control or supplemented by different amounts (0–100 ppm) of NanoComposix silver nanospheres exhibiting a size of 200 nm. Silver has been applied after (!) growth of P. verrucosum.
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Relative growth density reflecting the growth rates of Penicillium verrucosum supplemented by NanoComposix SiO2 nanospheres.
2016Co-Authors: Kathrin Kotzybik, Volker Gräf, Lena Kugler, Dominic A. Stoll, Ralf Greiner, Rolf Geisen, Markus Schmidt-heydtAbstract:Penicillium verrucosum incubated 7 days at 25°C under shaking of 230 rpm in MEA-liquid medium, supplemented by different amounts (0–2,500 ppm) of NanoComposix SiO2 nanospheres exhibiting sizes of 20 nm, 50 nm, 100 nm and 200 nm. Significant differences (P < 0.05) are indicated with an asterisk. The growth rate is specified as relative growth density. Data in S2 data set.