Uporaba β-galaktozidaze na področju živilstva in prehrane

Nika ŽIBRAT, Mihaela SKRT, Polona JAMNIK

Povzetek


β-galaktozidaza je encim s hidrolitično in transgalaktozilacijsko aktivnostjo. Vrsta aktivnosti je odvisna od izvora encima. V industriji uporabljene β-galaktozidaze so pridobljene z rekombinantno produkcijo iz nitastih gliv Aspergillus sp. in kvasovk Kluyveromyces sp. V zadnjem času se vedno bolj preučujejo β-galaktozidaze, ki optimalno delujejo pri nizkih ali visokih temperaturah. V industrijskih procesih se β-galaktozidaza uporablja v obliki prostega encima ali v imobilizirani obliki. Imobilizacija pogosto ponuja večjo stabilnost encima, možnost ponovne uporabe ter znižanje stroškov. β-galaktozidaza se pretežno uporablja na področju živilstva in prehrane, v zadnjem času pa ima znatno vlogo tudi v medicini. Hidrolitična aktivnost β-galaktozidaze se že dolgo izkorišča za zmanjšanje vsebnosti laktoze v mleku, medtem ko z reakcijami transgalaktozilacije iz laktoze lahko sintetiziramo različne produkte, kot so galaktooligosaharidi, laktosaharoza in drugi. Prav slednji imajo velik potencial v živilski industriji zaradi pridobivanja izdelkov z zmanjšano vsebnostjo laktoze in izboljšanja prehranske vrednosti živil s proizvodnjo galaktooligosaharidov. Kljub temu je potrebno bolje razumeti reakcijske mehanizme kot tudi optimizirati procese, da bo uporaba encima za ta namen dosegla industrijsko raven.

Ključne besede


prehrana ljudi; živilska industrija; živilstvo; encimi; beta-galaktozidaza

Celotno besedilo:

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Literatura


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DOI: http://dx.doi.org/10.14720/aas.2017.110.1.1

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