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1

Future Applications of Apricot (Prunus Armeniaca Kaisa) ß Galactosidase in Dairy Industry

100%

Ansari S. A. , Satar R. , Zaidi S. K. , Khan M. J. , Naseer M. I. , Al-Qahtani M. H. , Maskat M. Y.

Polish Journal of Chemical Technology

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2014

|

tom 16

|

nr 3

74-79

EN

The present study demonstrates the immobilization of β galactosidase from apricots (Prunus armeniaca kaisa) on an inexpensive concanavalin A layered cellulose-alginate hybrid gel. Immobilized β galactosidase retained 78% of the initial activity after crosslinking by glutaraldehyde. It exhibited greater fraction of activity at both acidic and basic pH, and showed broad spectrum temperature optimum as compared to free enzyme. Moreover, immobilized enzyme exhibited higher thermal stability at 60°C and retained 80% of the original enzyme activity in presence of 3% galactose. The crosslinked immobilized enzyme showed improved hydrolysis of lactose from milk and whey in batch processes at 50°C as well as in continuous reactors operated at fl ow rate of 20 mL/h and 30 mL/h even after one month. Moreover, crosslinked adsorbed β galactosidase retained 76% activity even after its sixth repeated use, thereby promoting its use for lactose hydrolysis in various dairy products even for longer durations.

2

Hydrolysis of Lactose from Cheese Whey Using a Reactor with β-Galactosidase Enzyme Immobilised on a Commercial UF Membrane

100%

Regenhardt S. A. , Mammarella E. J. , Rubiolo A. C.

Chemical and Process Engineering

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2013

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tom 34

|

nr 3

375-385

EN

In this study, β-galactosidase enzyme from Kluyveromyces fragilis was immobilised on a commercial polyethersulfone membrane surface, 10 kDa cut-off. An integrated process, concerning the simultaneous hydrolysis-ultrafiltration of whey lactose was studied and working conditions have been fixed at 55°C and pH 6.9, the same conditions that are used for the industrial process of protein concentration. For the immobilisation, best results were obtained using 5% (v/v) of glutaraldehyde solution and 0.03 M galactose; the total activity recovery coefficient (TARC) was 44.2%. The amount of immobilised enzyme was 12.49 mg with a total activity of 86.3 LAU at 37°C, using 5% (w/v) lactose solution in phosphate buffer (100 mM pH 6.9). The stability of the immobilised enzyme was approximately 585 fold higher in comparison with the stability of free enzyme. Multipoint covalent immobilisation improves the stability of the enzyme, thereby enhancing the decision to use the membrane as a filtering element and support for the enzyme immobilisation.

3

Future applications of apricot (Prunus armeniaca kaisa) ß galactosidase in dairy industry

100%

Ansarin S. A. , Satar R. , Zaidi S. K. , Khan M. J. , Naseer M. I. , Al-Qahtani M. H. , Maskat M. Y.

Polish Journal of Chemical Technology

|

2014

|

tom Vol. 16, nr 3

74--79

EN

The present study demonstrates the immobilization of β galactosidase from apricots (Prunus armeniaca kaisa) on an inexpensive concanavalin A layered cellulose-alginate hybrid gel. Immobilized β galactosidase retained 78% of the initial activity after crosslinking by glutaraldehyde. It exhibited greater fraction of activity at both acidic and basic pH, and showed broad spectrum temperature optimum as compared to free enzyme. Moreover, immobilized enzyme exhibited higher thermal stability at 60oC and retained 80% of the original enzyme activity in presence of 3% galactose. The crosslinked immobilized enzyme showed improved hydrolysis of lactose from milk and whey in batch processes at 50oC as well as in continuous reactors operated at flow rate of 20 mL/h and 30 mL/h even after one month. Moreover, crosslinked adsorbed β galactosidase retained 76% activity even after its sixth repeated use, thereby promoting its use for lactose hydrolysis in various dairy products even for longer durations.

4

Hydrolysis of Lactose from Cheese Whey Using a Reactor with β-Galactosidase Enzyme Immobilised on a Commercial UF Membrane

88%

Regenhardt S. A. , Mammarella E. J. , Rubiolo A. C.

Chemical and Process Engineering

|

2013

|

nr 3

5

Hydrolysis of lactose from cheese whey using a reactor with [beta]-galactosidase enzyme immobilised on a commercial uf membrane

63%

Regenhardt S. A. , Mammarella E. J. , Rubiolo A. C.

Chemical and Process Engineering

|

2013

|

tom Vol. 34, nr 3

375--385

EN

In this study, [Beta]-galactosidase enzyme from Kluyveromyces fragilis was immobilised on a commercial polyethersulfone membrane surface, 10 kDa cut-off. An integrated process, concerning the simultaneous hydrolysis–ultrafiltration of whey lactose was studied and working conditions have been fixed at 55[degrees]C and pH 6.9, the same conditions that are used for the industrial process of protein concentration. For the immobilisation, best results were obtained using 5% (v/v) of glutaraldehyde solution and 0.03 M galactose; the total activity recovery coefficient (TARC) was 44.2%. The amount of immobilised enzyme was 12.49 mg with a total activity of 86.3 LAU at 37[degrees]C, using 5% (w/v) lactose solution in phosphate buffer (100 mM pH 6.9). The stability of the immobilised enzyme was approximately 585 fold higher in comparison with the stability of free enzyme. Multipoint covalent immobilisation improves the stability of the enzyme, thereby enhancing the decision to use the membrane as a filtering element and support for the enzyme immobilisation.

6

Żywieniowe i technologiczne uwarunkowania zmniejszania zawartości laktozy w mleku i produktach mlecznych

63%

Świątek M. , Bednarski W. , Śliwiński M.

Przemysł Spożywczy

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2018

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tom T. 72, nr 10

26--29

PL

W pracy omówiono znaczenie laktozy w żywieniu. Wskazano na problem hipolaktazji i nietolerancji laktozy, z istotnym wpływem czynników etnicznych i genetycznych. Przedstawiono możliwości diagnostyczne i sposoby leczenia nietolerancji laktozy. Opisano właściwości preparatów β-galaktozydazy oraz aspekty technologiczne pozyskiwania produktów z rozłożoną laktozą. Przedstawiono zalecenia dotyczące diety bezlaktozowej i wskazano na potrzebę zwiększenia asortymentu produktów z obniżoną zawartością laktozy. W pracy wskazano poziomy progowe laktozy w niektórych krajach UE, w odniesieniu do stosowania określeń „bez laktozy” i „niska zawartość laktozy”.

EN

This work discusses the importance of lactose in nutrition. The problem of hypolactasia and lactose intolerance is pointed out, with significant influence of ethnic and genetic factors. Diagnostic possibilities and methods of treatment of lactose intolerance are presented. The properties of β-galactosidase preparations and technological aspects of obtaining products with hydrolised lactose are discussed. Recommendations regarding a lactose-free diet are presented and the need to increase the range of products with reduced lactose content is indicated. This paper indicates the threshold levels of lactose in some EU countries with reference to the use of the terms “lactose-free” and “low-lactose”.

7

Immobilization of Aspergillus oryzae Β galactosidase on concanavalin A-layered calcium alginate-cellulose beads and its application in lactose hydrolysis in continuous spiral bed reactors

51%

Ansari S. A. , Husain Q.

Polish Journal of Chemical Technology

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2011

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tom Vol. 13, nr 4

15-20

EN

In this study, Aspergillus oryzae Β galactosidase was immobilized on concanavalin A layered calcium alginate-cellulose beads as a bioaffi nity support. Immobilized enzyme showed a remarkable broadening in temperature-activity profi les as compared to the native enzyme and exhibited 65% activity in the presence of 5% galactose. Michaelis constant (Km) was 2.57 mM and 5.38 mM for the free and the immobilized Β galactosidase, respectively. Crosslinked Β galactosidase showed greater catalytic activity in the presence of Mg2+ and was more stable during storage at 4°C for 6 weeks. Immobilized enzyme hydrolyzed 67% lactose in milk in 8 h and 85% lactose in whey in 9 h in the stirred batch process at 50oC. The continuous hydrolysis of lactose by crosslinked Β galactosidase in spiral bed reactor exhibited 93% and 88% hydrolysis of lactose at flow rate of 20 ml/h and 30 ml/h, after 1 month operation, respectively.