Calorimetric studies of thermal denaturation of β-lactoglobulin in the presence of polysaccharides
The thermal denaturation of β-lactoglobulin at pH 6 and 7 in the presence of polysaccharides was studied by differential scanning calorimetry. At neutral pH, the shape of differential scanning calorimetry curves was affected by polysaccharides and an increase of 2-3°C in the onset temperature of β-l...
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todo:paper_00236438_v35_n5_p393_Baeza2023-10-03T14:34:03Z Calorimetric studies of thermal denaturation of β-lactoglobulin in the presence of polysaccharides Baeza, R.I. Pilosof, A.M.R. Denaturation Polysaccharide Thermostability β-lactoglobulin The thermal denaturation of β-lactoglobulin at pH 6 and 7 in the presence of polysaccharides was studied by differential scanning calorimetry. At neutral pH, the shape of differential scanning calorimetry curves was affected by polysaccharides and an increase of 2-3°C in the onset temperature of β-lactoglobulin denaturation was observed. This tendency was magnified up to 10°C at low water contents. At pH 7, the apparent enthalpy changes and the activation energy (Ea) were larger for β-lactoglobulin + polysaccharides mixtures than for pure β-lactoglobulin. At pH 6 the transition temperatures, denaturation enthalpy and activation energy of pure β-lactoglobulin were highly increased and slight changes were observed with further addition of polysaccharides. The rate constants of conversion of native β-lactoglobulin at pH 7 indicate a lower conversion of β-lactoglobulin when heated in the presence of polysaccharides, in agreement with electrophoretic results. Nevertheless, the formation of larger protein aggregates is promoted. A general analysis of the calorimetric and kinetic data indicates that polysaccharides enhance the thermal stability of β-lactoglobulin at neutral pH due to a limited thermodynamic incompatibility between the biopolymers. At pH 6 this effect is minimised because of the prevailing stabilizing effect of pH and a decreased incompatibility between β-lactoglobulin and polysaccharides. Fil:Baeza, R.I. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Pilosof, A.M.R. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_00236438_v35_n5_p393_Baeza |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
Denaturation Polysaccharide Thermostability β-lactoglobulin |
| spellingShingle |
Denaturation Polysaccharide Thermostability β-lactoglobulin Baeza, R.I. Pilosof, A.M.R. Calorimetric studies of thermal denaturation of β-lactoglobulin in the presence of polysaccharides |
| topic_facet |
Denaturation Polysaccharide Thermostability β-lactoglobulin |
| description |
The thermal denaturation of β-lactoglobulin at pH 6 and 7 in the presence of polysaccharides was studied by differential scanning calorimetry. At neutral pH, the shape of differential scanning calorimetry curves was affected by polysaccharides and an increase of 2-3°C in the onset temperature of β-lactoglobulin denaturation was observed. This tendency was magnified up to 10°C at low water contents. At pH 7, the apparent enthalpy changes and the activation energy (Ea) were larger for β-lactoglobulin + polysaccharides mixtures than for pure β-lactoglobulin. At pH 6 the transition temperatures, denaturation enthalpy and activation energy of pure β-lactoglobulin were highly increased and slight changes were observed with further addition of polysaccharides. The rate constants of conversion of native β-lactoglobulin at pH 7 indicate a lower conversion of β-lactoglobulin when heated in the presence of polysaccharides, in agreement with electrophoretic results. Nevertheless, the formation of larger protein aggregates is promoted. A general analysis of the calorimetric and kinetic data indicates that polysaccharides enhance the thermal stability of β-lactoglobulin at neutral pH due to a limited thermodynamic incompatibility between the biopolymers. At pH 6 this effect is minimised because of the prevailing stabilizing effect of pH and a decreased incompatibility between β-lactoglobulin and polysaccharides. |
| format |
JOUR |
| author |
Baeza, R.I. Pilosof, A.M.R. |
| author_facet |
Baeza, R.I. Pilosof, A.M.R. |
| author_sort |
Baeza, R.I. |
| title |
Calorimetric studies of thermal denaturation of β-lactoglobulin in the presence of polysaccharides |
| title_short |
Calorimetric studies of thermal denaturation of β-lactoglobulin in the presence of polysaccharides |
| title_full |
Calorimetric studies of thermal denaturation of β-lactoglobulin in the presence of polysaccharides |
| title_fullStr |
Calorimetric studies of thermal denaturation of β-lactoglobulin in the presence of polysaccharides |
| title_full_unstemmed |
Calorimetric studies of thermal denaturation of β-lactoglobulin in the presence of polysaccharides |
| title_sort |
calorimetric studies of thermal denaturation of β-lactoglobulin in the presence of polysaccharides |
| url |
http://hdl.handle.net/20.500.12110/paper_00236438_v35_n5_p393_Baeza |
| work_keys_str_mv |
AT baezari calorimetricstudiesofthermaldenaturationofblactoglobulininthepresenceofpolysaccharides AT pilosofamr calorimetricstudiesofthermaldenaturationofblactoglobulininthepresenceofpolysaccharides |
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1782025538333835264 |