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Du Zhu - One of the best experts on this subject based on the ideXlab platform.
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nitrogen source significantly increases chaetomium globosum dx ths3 β glucuronidase production by controlling Fungal Morphology in submerged fermentation
Process Biochemistry, 2021Co-Authors: Junru Sun, Ya Wang, Yiwen Xiao, Boliang Gao, Du ZhuAbstract:Abstract Plant endophytic fungus Chaetomium globosum DX-THS3 can produce β-glucuronidase (GUS) for efficient hydrolysis of glycyrrhizin (GL) into more valuable compounds glycyrrhetinic acid monoglucuronide (GAMG). The low productivity of GUS and the lack of an effective strategy to control the fermentative Morphology of C. globosum DX-THS3 have significantly limited its industrial applications. In this study, the effects of nitrogen source on GUS production and morphological changes in C. globosum DX-THS3 were investigated in shake flasks. Results showed that peptone was the optimal nitrogen source and had 3.5-fold higher GUS production by C. globosum DX-THS3 than the unoptimized source. C. globosum DX-THS3 had small circular pellets 1.3 ± 0.65 mm under 7 g/L peptone. Furthermore, a 5 L bioreactor was used to produce GUS. Under the optimal fermentation conditions, the GUS activity reached 792.17 U/mL. This work provides a strategy for designing the Morphology of filamentous fungi by using nitrogen source in the industrial production of GAMG.
Licia Maria Pera - One of the best experts on this subject based on the ideXlab platform.
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orchestration an extracellular lipase production from aspergillus niger mya 135 biomass Morphology and Fungal physiology
AMB Express, 2021Co-Authors: Hebe Natalia Salvatierra, Mario Domingo Baigori, Erika Lucia Regner, Licia Maria PeraAbstract:The impact of biomass Morphology and culture conditions on Fungal fermentation was widely reviewed in the literature. In this work, we presented three independent experiments in order to evaluate the influence of some of those input factors on a lipase production separately by using the Aspergillus niger MYA 135 and the two-stage fermentation technique. Regarding the culture modality, the biomass was pre-grown in a first reactor. Then, the washed mycelium was transferred to a second reactor to continue the study. Firstly, linear effects of Fungal Morphology and several physiological parameters on a lipase production were explored using the Plackett–Burman design. The dispersed Fungal Morphology was confirmed as a proper quality characteristic for producing an extracellular lipase activity. Concerning the impact of the carbon source on the biomass pre-growth, the sucrose (E = 9.923, p < 0.001) and the l-arabinose (E = 4.198, p = 0.009) presented positive and significant effects on the enzyme production. On the contrary, the supplementation of 0.05 g/L CaCl2 displayed a highly negative and significant effect on this process (E = − 7.390, p < 0.001). Secondly, the relationship between the enzyme production and the input variables N:C ratio, FeCl3 and olive oil was explored applying the central composite design. Among the model terms, the N:C ratio of the production medium had the most negative and significant influence on the enzyme synthesis. Thus, it was concluded that a low N:C ratio was preferable to increase its production. In addition, the bifunctional role of FeCl3 on this fungus was presented. Thirdly, a prove of concept assay was also discussed.
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tailoring Fungal Morphology of aspergillus niger mya 135 by altering the hyphal Morphology and the conidia adhesion capacity biotechnological applications
AMB Express, 2013Co-Authors: Veronica Leticia Colin, Mario Domingo Baigori, Licia Maria PeraAbstract:Current problems of filamentous fungi fermentations and their further successful developments as microbial cell factories are dependent on control Fungal Morphology. In this connection, this work explored new experimental procedures in order to quantitatively check the potential of some culture conditions to induce a determined Fungal Morphology by altering both hyphal Morphology and conidia adhesion capacity. The capacity of environmental conditions to modify hyphal Morphology was evaluated by examining the influence of some culture conditions on the cell wall lytic potential of Aspergillus niger MYA 135. The relative value of the cell wall lytic potential was determined by measuring a cell wall lytic enzyme activity such as the mycelium-bound β-N-acetyl-D-glucosaminidase (Mb-NAGase). On the other hand, the quantitative value of conidia adhesion was considered as an index of its aggregation capacity. Concerning microscopic Morphology, a highly negative correlation between the hyphal growth unit length (lHGU) and the specific Mb-NAGase activity was found (r = -0.915, P < 0.001). In fact, the environment was able to induce highly branched mycelia only under those culture conditions compatible with specific Mb-NAGase values equal to or higher than 190 U gdry.wt -1. Concerning macroscopic Morphology, a low conidia adhesion capacity was followed by a dispersed mycelial growth. In fact, this study showed that conidia adhesion units per ml equal to or higher than 0.50 were necessary to afford pellets formation. In addition, it was also observed that once the pellet was formed the lHGU had an important influence on its final diameter. Finally, the biotechnological significance of such results was discussed as well.
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effect of environmental conditions on extracellular lipases production and Fungal Morphology from aspergillus niger mya 135
Journal of Basic Microbiology, 2010Co-Authors: Veronica Leticia Colin, Mario Domingo Baigori, Licia Maria PeraAbstract:Under the current assay conditions, lipase production in mineral medium was only detected in the presence of vegetable oils, reaching the highest specific activity with olive oil. In this way, effect of different environmental conditions on Fungal Morphology and olive oil-induced extracellular lipases production from Aspergillus niger MYA 135 was studied. It was observed that addition of 1.0 g l–1 FeCl3to the medium encouraged filamentous growth and increased the specific activity 6.6 fold after 4 days of incubation compared to the control. However, major novelty of this study was the satisfactory production of an acidic lipase at initial pH 3 of the culture medium (1.74 ± 0.06 mU μg–1), since its potencial applications in food and pharmaceutical industry are highly promising. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Mario Domingo Baigori - One of the best experts on this subject based on the ideXlab platform.
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orchestration an extracellular lipase production from aspergillus niger mya 135 biomass Morphology and Fungal physiology
AMB Express, 2021Co-Authors: Hebe Natalia Salvatierra, Mario Domingo Baigori, Erika Lucia Regner, Licia Maria PeraAbstract:The impact of biomass Morphology and culture conditions on Fungal fermentation was widely reviewed in the literature. In this work, we presented three independent experiments in order to evaluate the influence of some of those input factors on a lipase production separately by using the Aspergillus niger MYA 135 and the two-stage fermentation technique. Regarding the culture modality, the biomass was pre-grown in a first reactor. Then, the washed mycelium was transferred to a second reactor to continue the study. Firstly, linear effects of Fungal Morphology and several physiological parameters on a lipase production were explored using the Plackett–Burman design. The dispersed Fungal Morphology was confirmed as a proper quality characteristic for producing an extracellular lipase activity. Concerning the impact of the carbon source on the biomass pre-growth, the sucrose (E = 9.923, p < 0.001) and the l-arabinose (E = 4.198, p = 0.009) presented positive and significant effects on the enzyme production. On the contrary, the supplementation of 0.05 g/L CaCl2 displayed a highly negative and significant effect on this process (E = − 7.390, p < 0.001). Secondly, the relationship between the enzyme production and the input variables N:C ratio, FeCl3 and olive oil was explored applying the central composite design. Among the model terms, the N:C ratio of the production medium had the most negative and significant influence on the enzyme synthesis. Thus, it was concluded that a low N:C ratio was preferable to increase its production. In addition, the bifunctional role of FeCl3 on this fungus was presented. Thirdly, a prove of concept assay was also discussed.
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tailoring Fungal Morphology of aspergillus niger mya 135 by altering the hyphal Morphology and the conidia adhesion capacity biotechnological applications
AMB Express, 2013Co-Authors: Veronica Leticia Colin, Mario Domingo Baigori, Licia Maria PeraAbstract:Current problems of filamentous fungi fermentations and their further successful developments as microbial cell factories are dependent on control Fungal Morphology. In this connection, this work explored new experimental procedures in order to quantitatively check the potential of some culture conditions to induce a determined Fungal Morphology by altering both hyphal Morphology and conidia adhesion capacity. The capacity of environmental conditions to modify hyphal Morphology was evaluated by examining the influence of some culture conditions on the cell wall lytic potential of Aspergillus niger MYA 135. The relative value of the cell wall lytic potential was determined by measuring a cell wall lytic enzyme activity such as the mycelium-bound β-N-acetyl-D-glucosaminidase (Mb-NAGase). On the other hand, the quantitative value of conidia adhesion was considered as an index of its aggregation capacity. Concerning microscopic Morphology, a highly negative correlation between the hyphal growth unit length (lHGU) and the specific Mb-NAGase activity was found (r = -0.915, P < 0.001). In fact, the environment was able to induce highly branched mycelia only under those culture conditions compatible with specific Mb-NAGase values equal to or higher than 190 U gdry.wt -1. Concerning macroscopic Morphology, a low conidia adhesion capacity was followed by a dispersed mycelial growth. In fact, this study showed that conidia adhesion units per ml equal to or higher than 0.50 were necessary to afford pellets formation. In addition, it was also observed that once the pellet was formed the lHGU had an important influence on its final diameter. Finally, the biotechnological significance of such results was discussed as well.
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effect of environmental conditions on extracellular lipases production and Fungal Morphology from aspergillus niger mya 135
Journal of Basic Microbiology, 2010Co-Authors: Veronica Leticia Colin, Mario Domingo Baigori, Licia Maria PeraAbstract:Under the current assay conditions, lipase production in mineral medium was only detected in the presence of vegetable oils, reaching the highest specific activity with olive oil. In this way, effect of different environmental conditions on Fungal Morphology and olive oil-induced extracellular lipases production from Aspergillus niger MYA 135 was studied. It was observed that addition of 1.0 g l–1 FeCl3to the medium encouraged filamentous growth and increased the specific activity 6.6 fold after 4 days of incubation compared to the control. However, major novelty of this study was the satisfactory production of an acidic lipase at initial pH 3 of the culture medium (1.74 ± 0.06 mU μg–1), since its potencial applications in food and pharmaceutical industry are highly promising. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Shangtian Yang - One of the best experts on this subject based on the ideXlab platform.
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a novel honeycomb matrix for cell immobilization to enhance lactic acid production by rhizopus oryzae
Bioresource Technology, 2010Co-Authors: Zhen Wang, Yuanliang Wang, Shangtian Yang, Runguang Wang, Huiqing RenAbstract:Abstract A new support matrix inspired by honeycomb was developed for cell immobilization to control Fungal Morphology and enhance mass transfer in bioreactor for lactic acid production by Rhizopus oryzae . The immobilization matrix composed of asterisk-shaped fibrous matrices in a honeycomb configuration provided high surface areas for cell attachment and biofilm growth. More than 90% of inoculated spores were adsorbed onto the matrices within 6–8 h and after 10 h there was no suspended cell in the fermentation broth, indicating a 100% immobilization efficiency. Compared to free-cell fermentation, lactic acid production increased ∼70% (49.5 g/L vs. 29.3 g/L) and fermentation time reduced 33% (48 h vs. 72 h) in shake-flasks with 80 g/L initial glucose. The immobilized-cell fermentation was evaluated for its long-term performance in a bubble-column bioreactor operated in a repeated batch mode for nine cycles in 36 days. The highest lactic acid production was 68.8 g/L, corresponding to a volumetric productivity of 0.72 g/L h and 93.4% (w/w) lactic acid yield from consumed glucose. The overall yield and productivity were 77.6% and 0.57 g/L h, respectively. The fermentation can be improved by increasing aeration and mixing in the bubble-column bioreactor.
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production of gfp and glucoamylase by recombinant aspergillus niger effects of fermentation conditions on Fungal Morphology and protein secretion
Biotechnology Progress, 2005Co-Authors: Mylene Talabardon, Shangtian YangAbstract:The effect of filamentous Fungal Morphology on heterologous protein secretion was investigated using the recombinant Aspergillus niger strain AB4.1[pgpdAGLAGFP], which contained the gene coded for the GLA-GFP (glucoamylase-green fluorescence protein) fusion protein. Three culturing systems were studied to develop different morphological forms of the fungus. Free-cell cultures in conventional stirred-tank bioreactors grew in pellet form with various sizes depending on culturing conditions. Cells immobilized on cotton cloth grew in mycelial form in a rotating fibrous bed (RFB) and a static fibrous bed (SFB) bioreactors. The expression of the fusion protein was growth-associated and dependent on the Fungal Morphology. Immobilized cells produced 10-fold more GFP and glucoamylase than well-oxygenated free-cell pellets. In free-cell cultures, excretion of the fusion protein occurred mainly from cell autolysis, when oxygen or nutrient were depleted, whereas protein secretion took place from the beginning of the fermentation in immobilized-cell cultures. Also, protein secretion was found to be strongly dependent on Morphology. Small pellets of a 1-mm size secreted 82% of GFP produced, whereas 43% of GFP remained intracellular in larger pellets of 5 mm. Complete secretion of GFP was obtained with cells immobilized on the fibrous matrix. The improvement in heterologous protein synthesis and secretion can be attributed to the filamentous mycelial Morphology since protein secretion occurred predominantly at the tips of growing hyphae. Secretion of proteases occurred mainly in the stationary phase or when cell autolysis were induced by nutrient depletion and was not dependent on Morphology, although immobilizing the cells also reduced protease activity. The RFB bioreactor gave the best fermentation performance because of its ability to control the cell Morphology that was amenable to efficient oxygen transfer and protein secretion.
Mark R. Marten - One of the best experts on this subject based on the ideXlab platform.
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Effect of cycle time on Fungal Morphology, broth rheology, and recombinant enzyme productivity during pulsed addition of limiting carbon source
Biotechnology and bioengineering, 2005Co-Authors: Swapnil Bhargava, Kevin S. Wenger, Kishore Rane, Vanessa Rising, Mark R. MartenAbstract:For many years, high broth viscosity has remained a key challenge in large-scale filamentous Fungal fermentations. In previous studies, we showed that broth viscosity could be reduced by pulsed addition of limiting carbon during fed-batch fermentation. The objective in this study was to determine how changing the frequency of pulsed substrate addition affects Fungal Morphology, broth rheology, and recombinant enzyme productivity. To accomplish this, a series of duplicate fed-batch fermentations were performed in 20-L fermentors with a recombinant glucoamylase producing strain of Aspergillus oryzae. The total cycle time for substrate pulsing was varied over a wide range (30-2,700 s), with substrate added only during the first 30% of each cycle. As a control, a fermentation was conducted with continuous substrate feeding, and in all fermentations the same total amount of substrate was added. Results show that the total biomass concentration remained relatively unaltered, while a substantial decrease in the mean projected area of Fungal elements (i.e., average size) was observed with increasing cycle time. This led to reduced broth viscosity and increased oxygen uptake rate. However, high values of cycle time (i.e., 900-2,700 s) showed a significant increase in Fungal conidia formation and significantly reduced recombinant enzyme productivity, suggesting that the fungi channeled substrate to storage compounds rather than to recombinant protein. In addition to explaining the effect of cycle time on fermentation performance, these results may aid in explaining the discrepancies observed on scale-up to larger fermentors.
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Fungal Morphology and fragmentation behavior in a fed batch aspergillus oryzae fermentation at the production scale
Biotechnology and Bioengineering, 2000Co-Authors: Vivek Shukla, Kevin S. Wenger, Andrew P Fordyce, Annemarie Gade Pedersen, Mark R. MartenAbstract:It is well known that high-viscosity fermentation broth can lead to mixing and oxygen mass transfer limitations. The seemingly obvious solution for this problem is to increase agitation intensity. In some processes, this has been shown to damage mycelia, affect Morphology, and decrease product expression. However, in other processes increased agitation shows no effect on productivity. While a number of studies discuss Morphology and fragmentation at the laboratory and pilot scale, there are relatively few publications available for production-scale Fungal fermentations. The goal of this study was to assess Morphology and fragmentation behavior in large-scale, fed-batch, Fungal fermentations used for the production of protein. To accomplish this, a recombinant strain of Aspergillus oryzae was grown in 80 m(3) fermentors at two different gassed, impeller power-levels (one 50% greater than the other). Impeller power is reported as energy dissipation/circulation function (EDCF) and was found to have average values of 29.3 +/- 1.0 and 22.0 +/- 0.3 kW m(-3) s(-1) at high and low power levels, respectively. In all batches, biomass concentration profiles were similar and specific growth rate was < 0.03 h(-1). Morphological data show hyphal fragmentation occurred by both shaving-off of external clump hyphae and breakage of free hyphae. The fragmentation rate constant (k(frag)), determined using a first-order model, was 5.90 and 5.80 h(-1) for high and low power batches, respectively. At the end of each batch, clumps accounted for only 25% of Fungal biomass, most of which existed as small, sparsely branched, free hyphal elements. In all batches, fragmentation was found to dominate Fungal growth and branching. We speculate that this behavior was due to slow growth of the culture during this fed-batch process.
