Effect of Media Composition and Growth Conditions on Production of β-Glucosidase by Aspergillus niger C-6

2005 ◽  
Vol 121 (1-3) ◽  
pp. 0347-0360 ◽  
Author(s):  
O. García-Kirchner ◽  
M. Segura-Granados ◽  
P. Rodríguez-Pascual
Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3084
Author(s):  
Hao Jing ◽  
Zhao Liu ◽  
Seng How Kuan ◽  
Sylvia Chieng ◽  
Chun Loong Ho

Recently, microbial-based iron reduction has been considered as a viable alternative to typical chemical-based treatments. The iron reduction is an important process in kaolin refining, where iron-bearing impurities in kaolin clay affects the whiteness, refractory properties, and its commercial value. In recent years, Gram-negative bacteria has been in the center stage of iron reduction research, whereas little is known about the potential use of Gram-positive bacteria to refine kaolin clay. In this study, we investigated the ferric reducing capabilities of five microbes by manipulating the microbial growth conditions. Out of the five, we discovered that Bacillus cereus and Staphylococcus aureus outperformed the other microbes under nitrogen-rich media. Through the biochemical changes and the microbial behavior, we mapped the hypothetical pathway leading to the iron reduction cellular properties, and found that the iron reduction properties of these Gram-positive bacteria rely heavily on the media composition. The media composition results in increased basification of the media that is a prerequisite for the cellular reduction of ferric ions. Further, these changes impact the formation of biofilm, suggesting that the cellular interaction for the iron(III)oxide reduction is not solely reliant on the formation of biofilms. This article reveals the potential development of Gram-positive microbes in facilitating the microbial-based removal of metal contaminants from clays or ores. Further studies to elucidate the corresponding pathways would be crucial for the further development of the field.


2013 ◽  
Vol 48 (1) ◽  
pp. 25-32 ◽  
Author(s):  
S Islam ◽  
B Feroza ◽  
AKMR Alam ◽  
S Begum

Pectinase activity among twelve different fungal strains, Aspergillus niger IM09 was identified as a potential one to produce maximal level 831 U/g at pH 4.0. Media composition, incubation temperature, incubation time, substrate concentration, aeration, inoculum size, assay temperature and nitrogen sources were found to effect pectinase activity. Moisture content did not affect the activity significantly. Media composition was varied to optimize the enzyme production in solid state fermentation. It was observed that the highest pectinase activity of 831.0 U/g was found to produce in presence of yeast extract as a nitrogen source in combination with ammonium sulfate in assay media. Aeration showed positive significant effects on pectinase production 755 U/g at 1000 ml flasks. The highest pectinase production was found at 2 g pectin (521 U/g) used as a substrate. Pectinolytic activity was found to have undergone catabolite repression with higher pectin concentration (205 U/g at 5 g pectin). The incubation period to achieve maximum pectinase activity by the isolated strain Aspergillus niger IM09 was 3 days, which is suitable from the commercial point of view. DOI: http://dx.doi.org/10.3329/bjsir.v48i1.15410 Bangladesh J. Sci. Ind. Res. 48(1), 25-32, 2013


2015 ◽  
Vol 14 (6) ◽  
pp. 602-615 ◽  
Author(s):  
Bert-Ewald Priegnitz ◽  
Ulrike Brandt ◽  
Khomaizon A. K. Pahirulzaman ◽  
Jeroen S. Dickschat ◽  
André Fleißner

ABSTRACTAdaptation to a changing environment is essential for the survival and propagation of sessile organisms, such as plants or fungi. Filamentous fungi commonly respond to a worsening of their growth conditions by differentiation of asexually or sexually produced spores. The formation of these specialized cell types is, however, also triggered as part of the general life cycle by hyphal age or density. Spores typically serve for dispersal and, therefore, translocation but can also act as resting states to endure times of scarcity. Eukaryotic differentiation in response to environmental and self-derived signals is commonly mediated by three-tiered mitogen-activated protein (MAP) kinase signaling cascades. Here, we report that the MAP kinase Fus3 of the black moldAspergillus niger(AngFus3) and its upstream kinase AngSte7 control vegetative spore formation and secondary metabolism. Mutants lacking these kinases are defective in conidium induction in response to hyphal density but are fully competent in starvation-induced sporulation, indicating that conidiation inA. nigeris triggered by various independent signals. In addition, the mutants exhibit an altered profile of volatile metabolites and secrete dark pigments into the growth medium, suggesting a dysregulation of the secondary metabolism. By assigning the AngFus3 MAP kinase pathway to the transduction of a potentially self-derived trigger, this work contributes to the unraveling of the intricate signaling networks controlling fungal differentiation. Moreover, our data further support earlier observations that differentiation and secondary metabolism are tightly linked in filamentous fungi.


1979 ◽  
Vol 31 (4) ◽  
pp. 134-138 ◽  
Author(s):  
N. Ramachandran ◽  
K. R. Sreekantiah ◽  
V. Sreenivasa Murthy

2020 ◽  
Vol 21 (9) ◽  
Author(s):  
Sri Sugiwati ◽  
Muhammad Hanafi ◽  
Hanifah Lioe ◽  
Maggy Suhartono

Abstract. Sugiwati S, Hanafi M, Lioe HN, Suhartono MT. 2020.  Effect of growth conditions on β-glucosidase production by local isolate of Aspergillus niger using rice bran substrate. Biodiversitas 21: 4058-4066. β-Glucosidase is the family of glycosyl hydrolase that have potential role in various food industry, such as in tea, wine and vanilla industries to increase the aroma and production of isoflavone aglycons in soybean flour. The present work produced β-glucosidase from local isolate of Aspergillus niger InaCC F57 under solid-state fermentation (SSF) using rice bran substrate. Fermentation process was made in various conditions with respect to carbon source as substrate, initial pH of fermentation medium, incubation time, water to substrate ratio, fermentation temperature, and addition of Mandels mineral salts solution. The results showed that activity of β-glucosidase was best at, i.e., 2.45 U/mL, with the use of rice bran as substrate. Furthermore, optimum condition for the highest production of β-glucosidase occurred at pH 2.0, incubation time of 5 days, water to substrate ratio of 1.5: 1, and incubation temperature of 32°C. Additionally, in optimum fermentation conditions, production of β-glucosidase could be enhanced up to 26.22% with the presence of Mandels mineral salts solution as compared to the control.


2019 ◽  
Vol 58 (5) ◽  
pp. 1-23
Author(s):  
Anton Z. Mindubaev ◽  
◽  
Elena K. Badeeva ◽  
Salima T. Minzanova ◽  
Lubov G. Mironova ◽  
...  

The biodegradation of white phosphorus is undoubtedly an amazing illustration of the adaptability of living organisms to adverse environmental factors. In addition, it is a potential basis for the creation of new, breakthrough methods for detoxifying substances of the first class danger. However, establishing the fact of biological destruction is only half the battle. It is essential to optimize the growth conditions of microbial cultures and P4 biodegradation for industrial cultivation. The presented study compared the growth of Aspergillus niger strain AM1 in culture media varying in composition but containing P4 as the sole source of phosphorus. Of the ten media, two in which Aspergillus grew the fastest were selected. These media were concluded to be optimal for growth. Comparing the compositions of the media and the growth rate of Aspergillus in them, we found a key component that is a favorable factor for the growth of AM1 and the biodegradation of white phosphorus. This component was sodium nitrate (NaNO3). It has also been shown that copper sulphate (CuSO4) has no effect on the growth of Aspergillus in media with white phosphorus, regardless of the composition of these media. This result is in harmony with our previous findings. Furthermore, in the present work, attempts to increase the concentration of white phosphorus in the culture medium to values above 1% are described for the first time. For this purpose, we added the following solvents to the culture media: dimethyl sulfoxide (DMSO) and diesel, in which white phosphorus dissolves relatively well. Apparently, the presence of these substances adversely affects the growth of Aspergill. Therefore, the problem of further increasing the concentration of P4 remains an unanswered.


Author(s):  
Feresteh Moradi ◽  
Marco Fiocchetti ◽  
Maria Marino ◽  
Christopher Moffatt ◽  
Jeffrey A. Stuart

Estradiol (E2) and selective estrogen receptor modulators (SERMs) have broad-ranging cellular effects that include mitochondrial respiration and reactive oxygen species (ROS) metabolism. Many of these effects have been studied using cell culture models. Recent advances have revealed the extent to which cellular metabolism is affected by the culture environment. Cell culture media with metabolite composition similar to blood plasma (e.g. Plasmax, HPLM) alter cellular behaviours including responses to drugs. Similar effects have been observed with respect to O2 levels in cell culture. Given these observations, we set out to determine whether the effects of E2 and SERMs are also influenced by media composition and O2 level during cell culture experiments. We analyzed mitochondrial network characteristics, cellular oxygen consumption rates, and cellular H2O2 production in C2C12 myoblasts growing in physiologic (5%) or standard cell culture (18%) O2 and in physiologic (Plasmax) or standard cell culture (DMEM) media. The cell culture conditions affected all measured parameters under basal conditions and changed how cells responded to E2 or SERMs. These results indicate that the effects of E2 and SERMs on various aspects of cell physiology strongly depends on growth conditions, which in turn emphasizes the need to consider this carefully in cell culture experiments.


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