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Culture conditions for the production of a tannase of Aspergillus tamarii IMI388810 (B)
SC Enemuor, FJC Odibo
African Journal of Biotechnology , 2009,
Abstract: Aspergillus tamarii IMI388810 (B) a tannic acid degrading fungus was isolated from soil inundated by effluent of a tannery at Oji River local Government Area of Enugu State, Nigeria. It was identified by CABI Bioscience, United Kingdom as A. tamarii with accession number of IMI 388810 (B). This fungus produced tannase in a fermentation medium M containing tannic acid as the only carbon source. Time course of enzyme synthesis by the fungus showed that the enzyme production followed logarithmic growth phase with maximum enzyme yield being obtained after 6 days corresponding to the culture pH of 3.8.
Involvement of Physical Parameters in Medium Improvement for Tannase Production by Aspergillus niger FETL FT3 in Submerged Fermentation  [PDF]
I. Darah,G. Sumathi,K. Jain,Lim Sheh Hong
Biotechnology Research International , 2011, DOI: 10.4061/2011/897931
Abstract: Aspergillus niger FETL FT3, a local extracellular tannase producer strain that was isolated from one of dumping sites of tannin-rich barks of Rhizophora apiculata in Perak, Malaysia. This fungus was cultivated in 250?mL Erlenmeyer flask under submerged fermentation system. Various physical parameters were studied in order to maximize the tannase production. Maximal yield of tannase production, that is, 2.81?U per mL was obtained on the fourth day of cultivation when the submerged fermentation was carried out using liquid Czapek-Dox medium containing (percent; weight per volume) 0.25% NaNO3, 0.1% KH2PO4, 0.05% MgSO4 ·7H2O, 0.05% KCl, and 1.0% tannic acid. The physical parameters used initial medium pH of 6.0, incubation temperature of , agitation speed of 200?rpm and inoculums size of ?spores/ ml. This research has showed that physical parameters were influenced the tannase production by the fungus with 156.4 percent increment. 1. Introduction Tannin acyl hydrolase (E.C.3.11.20) or commonly known as tannase is an inducible enzyme that catalyzes the hydrolysis of ester and depside bonds in hydrolysable tannin to produce glucose and gallic acid [1]. Tannase has wide applications especially in food, beverage, and pharmaceutical industries [2, 3]. It involves in the manufacturing of instant tea, coffee flavored, soft drinks, beer and wine where tannase is used to eliminate the water soluble precipitates [4–6]. Tannase is also used in debittering of fruit juices [7] and in improving vegetable fermentations [8]. Another important application of tannase is the production of gallic acid and propyl gallate [9, 10]. Gallic acid is used in the pharmaceutical industry for the synthesis of antibacterial drugs and also in the food industry as a substrate for the chemical synthesis of food preservatives, whereas propyl gallate is an important food additive to prevent food oxidation. Tannase is produced by a number of microorganisms and microbial. Tannase finds immense application in various industries due to its high stability and availability. Among the microbial tannase producers, filamentous fungi like Aspergillus [11–13], Rhizophs [14], Paecilomyces [15], and Penicillium [16] were studied extensively. Besides fungi, yeasts [17] and bacteria [18–22] have also been reported to produce tannase, but yeast was not extensively studied. In our study, we are reporting the production of tannase by Aspergillus niger FETL FT3 which we had successfully isolated from the dumping site of Rhizophora apiculata barks at the mangrove area in Perak, Malaysia, This fungal strain has
The Optimization of Aspergillus sp. GM4 Tannase Production under Submerged Fermentation  [PDF]
Alessandra Gon?alves de Melo, Rayssa Cristina Faria Pedroso, Luis Henrique Souza Guimar?es, José Guilherme Lembi Ferreira Alves, Eustáquio Souza Dias, Mário Lúcio Vilela de Resende, Patrícia Gomes Cardoso
Advances in Microbiology (AiM) , 2014, DOI: 10.4236/aim.2014.43019
Abstract:

Tannase is a hydrolytic enzyme that is involved in the biodegradation of tannins and it has biotechnological potential in the pharmaceutical, chemical, food and beverage industries. Microorganisms, especially filamentous fungi, are important tannase producers. The aims of this work were to find a potential tannase producer and to improve the cultivation conditions. Three Aspergillus species (A. japonicus 246A, A. tamarii 3 and Aspergillus sp. GM4) were investigated in different culture media (Adams, Czapeck, Khanna, M5 and Vogel) and inducers (1% and 2% tannic acid; 1% green tea; 1% methyl gallate; 1% gallic acid). Aspergillus sp. GM4 and Adams medium were selected. The tannase production by Aspergillus sp. GM4 in Adams medium was induced in the presence of 2% (w/v) tannic acid and gallic acid as carbon sources, while green tea was not able to induce tannase production. The Plackett-Burman screening design was performed with the variables MgSO4, KH2PO4, yeast extract, tannic acid, agitation rate and salt solution. The variables MgSO4 and agitation rate were selected for the optimization of tannase production using a Central Composite Rotatable Design. Under optimized conditions, a 2.66-fold increase in the enzyme production was observed with small modifications in the medium composition.

The use of alpha-methyl-D-glucoside, a synthetic analogue of maltose, as inducer of amylase by Aspergillus sp in solid-state and submerged fermentations
Moreira, Fabiana G.;Lenartovicz, Veridiana;Souza, Cristina G.M. de;Ramos, Edivan P.;Peralta, Rosane M.;
Brazilian Journal of Microbiology , 2001, DOI: 10.1590/S1517-83822001000100004
Abstract: the use of a methyl-d-glucoside (amg), a synthetic analogue of maltose, as carbon source and inducer of amylase synthesis to several species of aspergillus was studied in submerged and solid-state fermentations. among a group of ten species, a. tamarii, a. fumigatus and a. flavus were able to produce biomass and high specific amylolytic activity in submerged cultures containing amg as the only carbon source. in solid state fermentation, the enrichment of basal wheat bran or corn cob medium with amg increased up to 3 times the production of amylases. in both submerged and solid state fermentations, amg was more effective inducer of amylases than maltose and starch.
The use of a-methyl-D-glucoside, a synthetic analogue of maltose, as inducer of amylase by Aspergillus sp in solid-state and submerged fermentations  [cached]
Moreira Fabiana G.,Lenartovicz Veridiana,Souza Cristina G.M. de,Ramos Edivan P.
Brazilian Journal of Microbiology , 2001,
Abstract: The use of a methyl-D-glucoside (alphaMG), a synthetic analogue of maltose, as carbon source and inducer of amylase synthesis to several species of Aspergillus was studied in submerged and solid-state fermentations. Among a group of ten species, A. tamarii, A. fumigatus and A. flavus were able to produce biomass and high specific amylolytic activity in submerged cultures containing alphaMG as the only carbon source. In solid state fermentation, the enrichment of basal wheat bran or corn cob medium with alphaMG increased up to 3 times the production of amylases. In both submerged and solid state fermentations, alphaMG was more effective inducer of amylases than maltose and starch.
Characterization of a thermostable extracellular tannase produced under submerged fermentation by Aspergillus ochraceus
Gon?alves,Heloísa Bressan; Riul,Alana Jacomini; Quiapim,Andréa Carla; Jorge,Jo?o Atílio; Guimar?es,Luis Henrique Souza;
Electronic Journal of Biotechnology , 2012,
Abstract: background: tannases are enzymes that may be used in different industrial sectors as, for example, food and pharmaceutical. they are obtained mainly from microorganisms, as filamentous fungi. however, the diversity of fungi stays poorly explored for tannase production. in this article, aspergillus ochraceus is presented as a new source of tannase with interesting features for biotechnological applications. results: extracellular tannase production was induced when the fungus was cultured in khanna medium with tannic acid as carbon source. the extracellular tannase was purified 9-fold with 2% recovery and a single band corresponding to 85 kda was observed in sds-page. the native apparent molecular mass was estimated as 112 kda. optima of temperature and ph were 40oc and 5.0, respectively. the enzyme was fully stable from 40oc to 60oc during 1 hr. the activity was enhanced by mn2+ (33-39%) and nh4+ (15%). the purified tannase hydrolyzed tannic acid and methyl gallate with km of 0.76 mm and 0.72 mm, respectively, and vmax of 0.92 u/mg protein and 0.68 u/mg protein, respectively. the analysis of a partial sequence of the tannase encoding gene showed an open read frame of 567 bp and a sequence of 199 amino acids were predicted. tlc analysis revealed the presence of gallic acid as a tannic acid hydrolysis product. conclusion: the extracellular tannase produced by a. ochraceus showed distinctive characteristics such as monomeric structure and activation by mn2+, suggesting a new kind of fungal tannases with biotechnological potential. further, it was the first time that a partial gene sequence for a. ochraceus tannase was described.
RELATIONSHIP BETWEEN MORPHOLOGY, RHEOLOGY AND GLUCOAMYLASE PRODUCTION BY Aspergillus awamori IN SUBMERGED CULTURES
Pamboukian, C.R.D.;Facciotti, M.C.R.;Schmidell, W.;
Brazilian Journal of Chemical Engineering , 1998, DOI: 10.1590/S0104-66321998000300004
Abstract: the influence of inoculum preparation on aspergillus awamori morphology, broth rheology and glucoamylase synthesis in submerged cultures was investigated. a series of runs were performed in fermenters, using initial total reducing sugar concentrations of 20 g/l and 80 g/l. the inocula were prepared in a rotary shaker, at 35oc and 200 rev/min, using a spore concentration of 9.2 x 105 spores/ml and varying both cultivation time and medium ph during the spore germination step. three types of inocula were used: inoculum cultivated for 24 hours at an initial ph of 5.0, and inocula cultivated for 7 hours at both a ph of 2.5 and a ph of 5.5. regarding glucoamylase production, the inoculum which provided the best results was shaker cultivated for 7 hours at a ph of 2.5. this inoculum produced glucoamylase of about 1,221 u/l in the fermenter, which was between 20% and 30% higher than those obtained using other inocula.
RELATIONSHIP BETWEEN MORPHOLOGY, RHEOLOGY AND GLUCOAMYLASE PRODUCTION BY Aspergillus awamori IN SUBMERGED CULTURES  [cached]
Pamboukian C.R.D.,Facciotti M.C.R.,Schmidell W.
Brazilian Journal of Chemical Engineering , 1998,
Abstract: The influence of inoculum preparation on Aspergillus awamori morphology, broth rheology and glucoamylase synthesis in submerged cultures was investigated. A series of runs were performed in fermenters, using initial total reducing sugar concentrations of 20 g/L and 80 g/L. The inocula were prepared in a rotary shaker, at 35oC and 200 rev/min, using a spore concentration of 9.2 x 105 spores/mL and varying both cultivation time and medium pH during the spore germination step. Three types of inocula were used: inoculum cultivated for 24 hours at an initial pH of 5.0, and inocula cultivated for 7 hours at both a pH of 2.5 and a pH of 5.5. Regarding glucoamylase production, the inoculum which provided the best results was shaker cultivated for 7 hours at a pH of 2.5. This inoculum produced glucoamylase of about 1,221 U/L in the fermenter, which was between 20% and 30% higher than those obtained using other inocula.
Tannase production under solid and submerged culture by xerophilic strains of Aspergillus and their genetic relationships  [cached]
A. A. de la Cerda Gómez,M. H. Reyes Valdés,N. P. Meléndez Rentería,R. Rodríguez Herrera
Micología Aplicada Internacional , 2011,
Abstract: La enzima tanasa cataliza la hidrólisis de los enlaces éster del ácido tánico. En el presente estudio, se evalúo la producción de tanasa por siete cepas xerófilas de Aspergillus, utilizando medio de cultivo sólido y sumergido. Seis de las siete cepas fueron aisladas de una región semidesértica mexicana y una cepa fue utilizada como control (Aspergillus niger Aa-20). Las cepas fueron caracterizadas molecularmente por secuenciación de la región 18S del ADNr, con el objetivo de analizar sus relaciones genéticas. La cepa GH1 de Aspergillus niger produjo los niveles más altos de actividad enzimática en ambos sistemas de fermentación. Las especies identificadas fueron A. fumigatus, A. niger, A. ornatus, y A. rugulosus.
Quantification of the fractal nature of mycelial aggregation in Aspergillus niger submerged cultures
Maria Papagianni
Microbial Cell Factories , 2006, DOI: 10.1186/1475-2859-5-5
Abstract: Fractal analysis of distinct morphological forms produced by fermentation conditions that influence fungal morphology and acid production, showed that the two fractal dimensions DBS (box surface dimension) and DBM (box mass dimension) are very sensitive indexes, capable of describing morphological differences. The two box-counting methods applied (one applied to the whole mass of the mycelial particles and the other applied to their surface only) enabled evaluation of fractal dimensions for mycelial particles in this analysis in the region of DBS = 1.20–1.70 and DBM = 1.20–2.70. The global structure of sufficiently branched mycelia was described by a single fractal dimension D, which did not exceed 1.30. Such simple structures are true mass fractals (DBS = DBM = D) and they could be young mycelia or dispersed forms of growth produced by very dense spore inocula (108–109 spores/ml) or by addition of manganese in the medium. Mycelial clumps and pellets were effectively discriminated by fractal analysis. Fractal dimension values were plotted together with classic morphological parameters derived from image analysis for comparisons. Their sensitivity to treatment was analogous to the sensitivity of classic morphological parameters suggesting that they could be equally used as morphological descriptors.Starting from a spore, the mycelium develops as a mass fractal and, depending on culture conditions, it either turns to a surface fractal or remains a mass fractal. Since fractal dimensions give a measure of the degree of complexity and the mass filling properties of an object, it may be possible that a large number of morphological parameters which contribute to the overall complexity of the particles, could be replaced by these indexes effectively.In submerged culture the morphology of filamentous microorganisms varies between two extreme forms, pellets and free filaments, depending on culture conditions and the genotype of the applied strain. A close link between myceli
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