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1
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Influence of high pressure or autoclaving-cooling cycles and pullulanase treatment on buckwheat starch properties and resistant starch formation

100%
Gorecki A. R., Blaszczak W., Lewandowicz J., Le Thanh-Blicharz J., Penkacik K.
Polish Journal of Food and Nutrition Sciences
|
2018
|
tom 68
|
nr 3
Buckwheat starch was subjected to cycles of high pressure-cooling (P-CC) or autoclaving-cooling (A-CC) combined with pullulanase debranching to determine changes in resistant starch (RS) content, digestibility, rheological properties and microstructure. Native buckwheat starch had 11.9 g/kg of RS, while the highest RS content (58.7 g/kg) was reached after A-CC and 6 h of pullulanase treatment. Among the P-CC samples, the highest RS content (43.3 g/kg) was obtained after treatment with 600 MPa/9 min and 6 h pullulanase debranching. The digestibility of the starch samples was negatively correlated with RS content and its highest values were noted for native and P-CC 200 MPa preparations subjected to 2 and 16 h of pullulanase treatment (95.18–95.35%). Buckwheat starch A-CC preparations after 6 h of pullulanase treatment exhibited the lowest digestibility (85.87%). Rheological analysis of 6% starch pastes showed that all investigated samples demonstrated a non-Newtonian flow, pseudoplastic properties and thixotropy. The Ostwald de Waele rheological model was very well fitted to the flow curves of the investigated pastes (R2 >0.98). Both P-CC and A-CC reduced the consistency coeffi cient (K) and thixotropy values, while the flow behavior index (n) was increased only after P-CC treatment. The P-CC and A-CC treatment resulted in starch granule breakdown and porous gel structure formation, differing in surface properties.
2

Preperation of unbranched glucans by hydrolysis of starch of various botanical origin with pullulanase

100%
Kujawski M., Ziobro R., Gambus H.
Electronic Journal of Polish Agricultural Universities. Series Food Science and Technology
|
2003
|
tom 06
|
nr 2
The use of pullulanase preparation was checked as a method to obtain long unbranched glucans from native starch. Different starch sources as well as various solubilisation procedures were tried in order to choose the optimal one. Dissolving in NaOH proved to be suitable for all starch sources, while autoclave should be avoided in case of cereal starches. Potato starch gave clear solutions irrespective of solubilisation method, which were highly susceptible to enzymatic attack. Basing on the results obtained by size exclusion chromatography it was concluded that the time of incubation with the enzyme needed to completely degrade amylopectin molecules is short in comparison to the time needed to hydrolyse all available glycosidic bonds.
3

Pullulanase from rice endosperm

84%
Yamasaki Y., Nakashima S., Konno H.
Acta Biochimica Polonica
|
2008
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tom 55
|
nr 3
507-510
Pullulanase (EC 3.2.1.41) in non-germinating seeds was compared with that in germinating seeds. Moreover, pullulanase from the endosperm of rice (Oryza sativaL., cv. Hinohikari) seeds was isolated and its properties investigated. The pI value of pullulanase from seeds after 8 days of germination was almost equal to that from non-germinating seeds, which shows that these two enzymes are the same protein. Therefore, the same pullulanase may play roles in both starch synthesis during ripening and starch degradation during germination in rice seeds. The enzyme was isolated by a procedure that included ammonium sulfate fractionation, DEAE-cellulofine column chromatography, preparative isoelectric focusing, and preparative disc gel electrophoresis. The enzyme was homogeneous by SDS/PAGE. The molecular weight of the enzyme was estimated to be 100000 based on its mobility on SDS/PAGE and 105000 based on gel filtration with TSKgel super SW 3000, which showed that it was composed of a single unit. The isoelectric point of the enzyme was 4.7. The enzyme was strongly inhibited by β-cyclodextrin. The enzyme was not activated by thiol reagents such as dithiothreitol, 2-mercaptoethanol or glutathione. The enzyme most preferably hydrolyzed pullulan and liberated only maltotriose. The pullulan hydrolysis was strongly inhibited by the substrate at a concentration higher than 0.1%. The degree of inhibition increased with an increase in the concentration of pullulan. However, the enzyme hydrolyzed amylopectin, soluble starch and β-limit dextrin more rapidly as their concentrations increased. The enzyme exhibited α-glucosyltransfer activity and produced an α-1,6-linked compound of two maltotriose molecules from pullulan.
4

Characteristics of oligosaccharides produced by enzymatic hydrolysis of potato starch using mixture of pullulanases and alpha-amylases

84%
Krzyzaniak W., Bialas W., Olesienkiewicz A., Jankowski T., Grajek W.
Electronic Journal of Polish Agricultural Universities. Series Food Science and Technology
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2003
|
tom 06
|
nr 2
Kinetics of amylolytic hydrolysis of autoclaved and extruded potato starch using alpha-amylase and pullulanase mixtures were described. Maltodextrins with dextrose equivalent of 3, 5, 8 and 12 were obtained and their sugar compositions with HPLC method were analyzed. The low molecular sugar (PD 1-2) and oligosaccharide (PD 3-8) contents as well as relationship between dextrose equivalent of maltodextrins and oligosaccharide contents were determined.
5

Raw starch degradation by pullulanase

84%
Kujawski M., Ziobro R., Gambus H.
Acta Scientiarum Polonorum. Technologia Alimentaria
|
2002
|
tom 01
|
nr 2
Activity of two commercial pullulanase preparations has been compared with biochemical grade enzyme from Sigma. Of them PULLUZYME 750 was chosen as a reagent for hydrolysis of raw starch granules from different botanical species. The obtained results suggest that high amylose corn starch and native potato starch are more resistant to pullulanase action than wheat starch which under the action of this enzyme becomes slightly degraded.
6
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Próba zastosowania pullulanazy do otrzymywania liniowych glukanów ze skrobi ziemniaczanej

67%
Gambus H., Ziobro R., Jankowski T., Gumul D., Palasinski M.
Żywność Nauka Technologia Jakość
|
2004
|
tom 11
|
nr 1
41-54
W pracy podjęto próbę uzyskania liniowych glukanów przez wytrącenie ich z roztworu skrobi ziemniaczanej w 20% (v/v) DMSO, poddanej działaniu pululanazy zawartej w preparacie handlowym Pulluzyme 750 (ABM Chemicals). Strącanie przebiegało 3-etapowo. Po każdym etapie otrzymywano frakcje hydrolizatu, składające się z glukanów liniowych i rozgałęzionych. W uzyskanych frakcjach oznaczano zawartość liniowych łańcuchów skrobiowych, wielkość cząsteczek, tendencję do retrogradacji oraz przemiany fazowe metodą DSC. Najbardziej interesujące właściwości wykazała frakcja III składająca się głównie z krótkich łańcuchów amylozy i wykazująca największą tendencję do retrogradacji. Znaczna entalpia jej topnienia oraz wysoki zakres temperatury tej przemiany fazowej świadczą o dużym udziale krystalitów amylozowych, charakterystycznych dla skrobi opornej.
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