Response Surface Methodology Applied to the Enzymatic Synthesis of Galacto-oligosaccharides from Cheese Whey

Cristiane Reinaldo Lisboa,Luciana de Simoni Martinez,Renata Aguirre Trindade,Fátima Aparecida de Almeida Costa,Janaína Fernandes de Medeiros Burkert,Carlos André Veiga Burkert 한국식품과학회 2012 Food Science and Biotechnology Vol.21 No.6

In this study, a strategy was proposed for making galacto-oligossaccharides (GOS), a high valueadded product, from a byproduct of the dairy industry,cheese whey, using a commercial β-galactosidase from Kluyveromyces lactis (Lactozym® 3000L). The effects of the substrate concentration, temperature, and enzyme dosage were statistically studied and their optimum combinations were determined using response surface methodology. The increase in lactose concentration, temperature, and enzyme concentration favored a transgalactosylation reaction. The maximum values for GOS concentration (119.8 mg/mL)and yield (29.9%) in a 4 h process were obtained in the reaction system, composed of 400 mg/mL of lactose and 10 U/mL of enzyme at 40°C. Under these conditions, the lactose conversion was 68.7%. The maximum value for lactose conversion (87.8%) was observed at the same temperature and enzyme concentration, although the lactose level was 20%.

Extraction of Carotenoids from Phaffia rhodozyma: A Comparison between Different Techniques of Cell Disruption

Mariano Michelon,Thais de Matos de Borba,Ruan da Silva Rafael,Carlos André Veiga Burkert,Janaína Fernandes de Medeiros Burkert 한국식품과학회 2012 Food Science and Biotechnology Vol.21 No.1

The yeast Phaffia rhodozyma is known for producing carotenogenic pigments, commonly used in aquaculture feed formulation as well as in cosmetic,pharmaceutical, and food industries. Despite the high production of carotenoids from microorganisms by biotechnology, their use has limitation due to the cell wall resistance, which constitutes a barrier to the bioavailability of carotenoids. Therefore, there is a need to improve carotenoids recovering technique from microorganisms for the application of food industries. This study aimed to compare mechanical, chemical, and enzymatic techniques of cell disruption for extracting carotenoids produced by P. rhodozyma NRRL Y-17268. Among the techniques studied, the highest specific concentration of carotenoids (190.35 μg/g) resulted from the combined techniques of frozen biomass maceration using diatomaceous earth and enzymatic lysis at pH of the reaction medium of 4.5 at 55oC, with initial activity of β-1,3 glucanase of 0.6 U/mL for 30 min.

A successive ionic layer adsorption and reaction (SILAR) method to fabricate a layer-by-layer (LbL) MnO₂-reduced graphene oxide assembly for supercapacitor application

Jana, Milan,Saha, Sanjit,Samanta, Pranab,Murmu, Naresh Chandra,Kim, Nam Hoon,Kuila, Tapas,Lee, Joong Hee Elsevier 2017 Journal of Power Sources Vol.340 No.-

<P><B>Abstract</B></P> <P>A facile, cost effective and additive-free successive ionic layer adsorption and reaction (SILAR) technique is demonstrated to develop layer-by-layer (LbL) assembly of reduced graphene oxide (RGO) and MnO<SUB>2</SUB> (MnO<SUB>2</SUB>-RGO<SUB>SILAR</SUB>) on a stainless steel current collector, for designing light-weight and small size supercapacitor electrode. The transmission electron microscopy and field emission scanning electron microscopy images shows uniform distribution of RGO and MnO<SUB>2</SUB> in the MnO<SUB>2</SUB>-RGO<SUB>SILAR</SUB>. The LbL (MnO<SUB>2</SUB>-RGO<SUB>SILAR</SUB>) demonstrates improved physical and electrochemical properties over the hydrothermally prepared MnO<SUB>2</SUB>-RGO (MnO<SUB>2</SUB>-RGO<SUB>Hydro</SUB>). The electrochemical environment of MnO<SUB>2</SUB>-RGO<SUB>SILAR</SUB> is explained by constant phase element in the high frequency region, and a Warburg element in the low frequency region in the Z-View fitted Nyquist plot. The equivalent circuit of the MnO<SUB>2</SUB>-RGO<SUB>Hydro</SUB>, displays the co-existence of EDL and constant phase element, indicating inhomogeneous distribution of MnO<SUB>2</SUB> and RGO by the hydrothermal technique. An asymmetric supercapacitor device is designed with MnO<SUB>2</SUB>-RGO<SUB>SILAR</SUB> as positive electrode, and thermally reduced GO (TRGO) as negative electrode. The designed cell exhibits high energy density of ∼88 Wh kg<SUP>−1</SUP>, elevated power density of ∼23,200 W kg<SUP>−1</SUP>, and ∼79% retention in capacitance after 10,000 charge-discharge cycles.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Layer-by-layer assembly (LbL) of MnO<SUB>2</SUB> and reduced graphene oxide (RGO) is prepared. </LI> <LI> The LbL acts as single material with hybrid electrochemical properties. </LI> <LI> Uniform distribution of MnO<SUB>2</SUB> over RGO exhibits high specific capacitance. </LI> <LI> No organic binder is used to design the supercapacitor electrodes. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>The LbL RGO-MnO<SUB>2</SUB> acts as single hybrid electro-active material and the hydrothermally prepared RGO-MnO<SUB>2</SUB> provides mixed properties of two materials.</P> <P>[DISPLAY OMISSION]</P>

SOME PROPERTIES OF EXTENDED τ-HYPERGEOMETRIC FUNCTION

Jana, Ranjan Kumar,Maheshwari, Bhumika,Shukla, Ajay Kumar Korean Mathematical Society 2018 대한수학회논문집 Vol.33 No.4

Recently, Parmar [5] introduced a new extension of the ${\tau}$-Gauss hypergeometric function $_2R^{\tau}_1(z)$. The main object of this paper is to study this extended ${\tau}$-Gauss hypergeometric function and obtain its properties including connection with modified Bessel function of third kind and extended generalized hypergeometric function, several contiguous relations, differential relations, integral transforms and elementary integrals. Various special cases of our results are also discussed.

Growth of Ni–Co binary hydroxide on a reduced graphene oxide surface by a successive ionic layer adsorption and reaction (SILAR) method for high performance asymmetric supercapacitor electrodes

Jana, Milan,Saha, Sanjit,Samanta, Pranab,Murmu, Naresh Chandra,Kim, Nam Hoon,Kuila, Tapas,Lee, Joong Hee The Royal Society of Chemistry 2016 Journal of Materials Chemistry A Vol.4 No.6

<▼1><P>Ni–Co–BH–G was prepared by using a SILAR technique and the corresponding asymmetric supercapacitor showed an energy density of 92 W h kg<SUP>−1</SUP>.</P></▼1><▼2><P>A simple, additive-free, cost-effective and scalable successive ionic layer adsorption and reaction (SILAR) method is reported to prepare nickel–cobalt binary hydroxide (Ni–Co–BH) on a reduced graphene oxide (RGO) directing template over a macro-porous conductive nickel foam substrate. This green technique is not only considered as fundamental research interest, but also describes the commercial applications of supercapacitors to reduce the electrode fabrication cost. Three different Ni–Co–BH–G (Ni–Co–BH/RGO) composites are synthesised by tailoring the nickel–cobalt ratios. The flower-like 3D framework of Ni–Co–BH–G provides a porous nano-structure to facilitate the charge transfer and ion diffusion. The cathodic peak current density <I>vs.</I> square root of the scan rate slope values of cyclic voltammetry are consistent with specific capacitance (SC) retention (<I>vs.</I> current density) from charge–discharge curves and the diffusion time constant of the Nyquist plot of the Ni–Co–BH–G composites. Taking the advantage of 3D conductive mesoporous open framework, the Ni–Co–BH–G has provided an excellent SC of 2130 F g<SUP>−1</SUP> at 2 A g<SUP>−1</SUP>. An asymmetric supercapacitor device is designed with the optimized Ni–Co–BH–G as the positive electrode and concentrated HNO3 treated conducting carbon cloth (CCN) as the negative electrode. An excellent energy density of ∼92 W h kg<SUP>−1</SUP> and a high power density of ∼7.0 kW kg<SUP>−1</SUP> with lifetime stability up to 10 000 charge–discharge cycles (capacitance retention ∼ 80%) are provided by the asymmetric device. Four asymmetric devices have been assembled in series, which provided ∼5.6 V charge–discharge potential. The assembled system has powered a 5 V light-emitting diode (LED) successfully.</P></▼2>

Superior performance of asymmetric supercapacitor based on reduced graphene oxide-manganese carbonate as positive and sono-chemically reduced graphene oxide as negative electrode materials

Jana, M.,Kumar, J.S.,Khanra, P.,Samanta, P.,Koo, H.,Murmu, N.C.,Kuila, T. Elsevier Sequoia 2016 Journal of Power Sources Vol.303 No.-

A novel strategy to synthesize hierarchical rod like MnCO<SUB>3</SUB> on the reduced graphene oxide (RGO) sheets by a facile and cost-effective hydrothermal method is demonstrated. The chelating action of citric acid facilitates the formation a complex intermediate of Mn<SUP>2+</SUP> and citrate ions, which finally results a 3D MnCO<SUB>3</SUB>/RGO (MRGO) composite with high electrical conductivity (~1056 S m<SUP>-1</SUP>), good surface area (59 m<SUP>2</SUP> g<SUP>-1</SUP>) and high pore volume (0.3 cm<SUP>3</SUP> g<SUP>-1</SUP>). The specific capacitance (SC) of the MRGO composite is ~1120 F g<SUP>-1</SUP> at a current density of 2 A g<SUP>-1</SUP> in three electrode system. An asymmetric device has been designed with MRGO as positive and sono-chemically reduced RGO (SRGO) as negative electrode material. The asymmetric device (MRGO//SRGO) shows the SC of ~318 F g<SUP>-1</SUP> (at 2 A g<SUP>-1</SUP>) and energy density of ~113 W h kg<SUP>-1</SUP> (at 1600 W kg<SUP>-1</SUP>). The true energy density (1.7 W h kg<SUP>-1</SUP>) has been calculated considering the total weight of the device. The MRGO//SRGO device can power a wall clock for ~13 min after full charging. The Nyquist plot of the asymmetric cell has been simulated with Z-View software to measure the solution resistance, charge-transfer resistance and Warburg elements.

Bio-reduction of graphene oxide using drained water from soaked mung beans (Phaseolus aureus L.) and its application as energy storage electrode material

Jana, M.,Saha, S.,Khanra, P.,Murmu, N.C.,Srivastava, S.K.,Kuila, T.,Lee, J.H. Elsevier 2014 Materials science and engineering B. Advanced Func Vol.186 No.-

Green reduction of graphene oxide (GO) using drained water from soaked mung beans (Phaseolus aureus L.) has been demonstrated. In comparison to the toxic and hazardous reducing chemicals, the drained water from soaked mung beans (P. aureus L.) is completely green reducing agent, the reduction process is very simple and cost effective. The removal of oxygen containing functional groups of GO has been confirmed by UV-vis, Fourier transform infrared and X-ray photoelectron spectroscopy analysis. Morphological characterization of rGO has been performed by atomic force and transmission electron microscopy analysis. Electrochemical performances of rGO have been evaluated by cyclic voltammetry (CV), charge-discharge and electrochemical impedance spectroscopy techniques. The specific capacitance (SC) of rGO has been found to be 137Fg<SUP>-1</SUP> at a current density of 1.3Ag<SUP>-1</SUP>. The retention in SC is more than 98% after 1000 charge-discharge cycles suggesting long-term electrochemical cyclic stability as supercapacitor electrode materials.

On the Margins of Czech Fairy Tales

Jana Bischofov? 아시아중동부유럽학회 2002 동유럽발칸학 Vol.4 No.1

B3S monolayer: prediction of a high-performance anode material for lithium-ion batteries

Jana, Saibal,Thomas, Siby,Lee, Chi Ho,Jun, Byeongsun,Lee, Sang Uck Royal Society of Chemistry 2019 Journal of Materials Chemistry A Vol.7 No.20

<P>To mitigate the ever-growing global temperature rise, renewable energy is needed and use of fossil fuels has to be reduced on an urgent basis. Next-generation renewable energy technology demands electrode materials with suitable structural, electronic, and mechanical properties. Through particle swarm-intelligence and first-principles structure calculations, we have designed a new novel B3S monolayer, which is dynamically, mechanically, and thermally stable and of higher cohesive energy compared to synthesized B2S3 thus ensuring the feasibility of experimental synthesis. As an anode material, the B3S monolayer can be expected to have high performance with high storage capacity (1662 mA h g<SUP>−1</SUP>), low open-circuit voltage (∼0.16 V) and a low lithium diffusion barrier (<I>E</I>a < 0.4 eV). Furthermore, the metallicity of the B3S monolayer is sustained after lithium adsorption, indicating good electrical conductivity and battery operating cycle. Our results clarify that these intriguing properties make B3S monolayer an appealing candidate for anode material in lithium-ion batteries.</P>

Slide Session : OS-GAS-06 ; Gastroenterology : Non-Resorbable Chelating Polymeric Beads as Potential Treatment of Wilson`s Disease

( Jana Mattova ),( Pavla Pouckova ),( Petr Urbanek ),( Martin Hruby ),( Jan Kucka ),( Miroslav Vetrik ),( Michaela Skodova ),( Petr Stepanek ),( Milos Petrik ),( Zbynek Novy ) 대한내과학회 2014 대한내과학회 추계학술대회 Vol.2014 No.1

Background: Wilson`s disease is a genetic disorder caused by a malfunction of ATPase 7B that leads to high accumulation of copper in the organism and consequent toxic effects. We propose a gentle therapy to eliminate the excessive copper content with oral administration of insoluble non-resorbable polymer sorbents containing selective chelating groups for copper ions (Cu²<sup>+</sup> ions). Methods: Polymeric beads with the chelating agents triethylenetetramine, N,N-di(2-pyridylmethyl)amine and 8-hydroxyquinoline were investigated. We performed a long term experiment with Wistar rats fed a diet containing the particular polymers. Further, we investigated non-resorbability of polymeric beads. We measured organ radioactivity after oral administration of 8-hydroxyquinoline on polymer radiolabelled with iodine-125. Non-resorbability was also tested with small animal PET/CT imaging (using copper-64) in NMR mice. Results: In a long-term experiment with Wistar rats fed a diet containing the polymers, we have found that there were no signs of polymer toxicity and the addition of polymers to the diet led to a significant reduction in the copper contents in the kidneys, brains, and livers of the rats. 8-hydroxyquinoline on polymer radiolabelled with iodine-125 was not absorbed from the digestive tract after oral administration. Non-resorbability was also confirmed with PET/CT imaging. Conclusions: We have shown that polymers containing specific ligands could potentially be novel therapeutics for Wilson`s disease. Polymeric beads significantly reduced copper content in selected organs and they are non-resorbable from digestive tract and fully eliminated in feces after oral administration.