Amylase Digestion Research Articles

Novel Porous Starch Granules Fabricated Using Controlled Lipase-Amylase Treatments: Application as Delivery Systems and Resistant Starches.

Porous starch granules (PSGs) are promising biomaterials for the encapsulation, protection, and delivery of bioactive ingredients. In this study, a lipase treatment was first used to generate pores in native starch granules, and then α-amylase was used to enlarge these pores. Electron and fluorescence microscopy analysis showed that the lipase treatment exposed the starch molecules located below the lipid-rich regions on the starch granule surfaces, which increased the swelling of the granules in aqueous solutions. Moreover, lipase treatment caused the surrounding areas to become more loosely packed, which facilitated subsequent starch hydrolysis and the formation of large internal cavities. Fourier transform infrared spectroscopy, X-ray diffraction, and thermogravimetric analyses provided further insights, these methods showed that the short-range order, long-range order, and thermal stability of the PSGs was enhanced by the sequential lipase-amylase modification. PSGs were highly resistant to amylase digestion and had strong adsorption capacity to hydrophobic and hydrophilic substances. This study shows that a combined lipase-amylase treatment can be used to fabricate PSGs, which may have health benefits due to their low digestibility and ability to encapsulate bioactive agents. These PSGs may therefore be suitable for application in the functional food, supplement, personal care, and pharmaceutical industries.

The Construction of Sodium Alginate/Carboxymethyl Chitosan Microcapsules as the Physical Barrier to Reduce Corn Starch Digestion.

To enhance the resistant starch (RS) content of corn starch, in this work, carboxymethyl chitosan/corn starch/sodium alginate microcapsules (CMCS/CS/SA) with varying concentrations of SA in a citric acid (CA) solution were designed. As the SA concentration increased from 0.5% to 2%, the swelling of the CMCS/CS/SA microcapsule decreased from 15.28 ± 0.21 g/g to 3.76 ± 0.66 g/g at 95 °C. Comparatively, the onset, peak, and conclusion temperatures (To, Tp, and Tc) of CMCS/CS/SA microcapsules were higher than those of unencapsulated CS, indicating that the dense network structure of microcapsules reduced the contact area between starch granules and water, thereby improving thermal stability. With increasing SA concentration, the intact and dense network of CMCS/CS/SA microcapsules remained less damaged after 120 min of digestion, suggesting that the microcapsules with a high SA concentration provided better protection to starch, thereby reducing amylase digestibility. Moreover, as the SA concentration increased from 0.5% to 2%, the RS content of the microcapsules during in vitro digestion rose from 42.37 ± 0.07% to 57.65 ± 0.45%, attributed to the blocking effect of the microcapsule shell on amylase activity. This study offers innovative insights and strategies to develop functional starch with glycemic control properties, holding significant scientific and practical value in preventing diseases associated with abnormal glucose metabolism.

Whey protein isolate regulates the oral processing characteristics of lotus root starch

This study aimed to investigate the influence of different levels of added whey protein isolate (WPI) on the oral processing characteristics of lotus root starch (LRS). The IDDSI test results indicated that WPI-LRS composite gels could be classified as foods suitable for individuals with dysphagia. During in vitro oral digestion process, addition of WPI increased the viscosity of the composite system. When the amount of WPI reached 100% (w/w), the reducing sugar content decreased from 105.23 to 42.35 mg. Inverted fluorescence images revealed that WPI formed a continuous network structure in the starch matrix and served as a barrier against amylase digestion. Different levels of WPI addition had diverse effects on the oral friction characteristics and rheological properties of the composite system. As the protein addition amounts were lower than 45% (w/w), the composite gels had lower lubrication properties and elastic modulus. While as the addition levels were higher than 45% (w/w), the composite gels exhibited higher lubrication properties and elastic modulus. Texture analysis indicated that the hardness value of the composite gel increased from 0.65 N for the individual LRS gel to 4.75 N for the composite gel of LRS+100% WPI. Furthermore, it was found through low-field nuclear magnetic analysis that the addition of WPI restricted the free movement of water molecules and enhanced the water-holding capacity of the composite gels.

Stability of starch-proanthocyanidin complexes to in-vitro amylase digestion after hydrothermal processing.

Proanthocyanidins (PA) form poorly digestible complexes with starch. The study examined amylase degradation mechanism and hydrothermal stability of starch-PA complexes. Sorghum-derived PA was complexed with wheat starch, reconstituted into flour (10% gluten added) and processed into crackers and pancakes. In vitro digestion profile of the complexes and products were characterized. The starch-PA complexes retained more (34-84%) fragments with degree of polymerization (DP)>6,000 after 120min digestion than controls (0-21%). Debranching further revealed higher retention of DP 11 - 30 chains in the digested starch-PA complexes than controls, suggesting amylopectin complexation contributed to reduced starch digestion. Starch-PA complexes retained reduced digestibility (50-56% higher resistant starch vs controls) in the cracker, but not pancake model. However, removing gluten from the pancake formulation restored the reduced digestibility of the starch-PA complexes. The starch-PA complexes are stable to hydrothermal processing, but can be disrupted by hydrophobic gluten proteins under excess moisture conditions.

Efek Perbedaan Temperatur terhadap Aktivitas Tripsin-Like dan Amilase Digesti Ikan Lunjar (Rasbora lateristriata Blkr.)

Previous studies related to digestive enzyme activity have been carried out, but there is no information related to the effect of temperature on the trypsin-like activity and digestive amylase in Rsbora lateristriata. Therefore, the purpose of this study was to determine the effect of temperature differences on the activity of trypsin-like and amylase digestion of Rasbora lateristriata fish. The temperature treatments applied were 20, 30, 40, 50, 60, and 70ºC and each treatment was repeated five times. A total of 125 Rasbora fish with a body weight of 0.81 ± 0.09 grams were used in this study. Trypsin-like and amylase activities were measured using a spectrophotometer. The results showed that there were significant differences (p < 0.05) in the trypsin-like and amylase activities at different temperatures. The trypsin-like activity was not significantly different (p < 0.05) between 20-50ºC, but the activity was lower at 60-70ºC. Amylase activity at 30°C and 40°C was not significantly different (p < 0.05), but significantly different from 20, 50, 60, and 70°C. In conclusion, trypsin-like decreased activity at 60°C and amylase at 50°C.

Simple thermal and freezing treatments to improve absorption capacity and alter digestibility of canna starch granules

Swollen canna starches (SCS) were prepared by controlled heating of unmodified and heat-moisture treated (HMT) starch suspensions at sub-gelatinization temperatures; subsequently, freezing was conducted to stabilize the structure of the SCS. Sizes of both unmodified and HMT swollen granules increased with increasing heating temperatures (up to 2.5 times), and freezing resulted in a significant reduction of granular size. The absorption capacities of the swollen starches increased up to 6 times for water and 3 times for tributyrin and palm oil compared to unmodified starch. The differences in absorption capacities of the unmodified and HMT swollen starches were small. Freezing the swollen starches tended to decrease oil and water absorptions, except for unmodified starch swollen at 70 °C, where freezing increased water absorption. Freezing significantly decreased the susceptibility of the swollen unmodified starches to amylase digestion and slowed down the digestion of the swollen HMT starches.

Novel insight into valorization of potato peel biomass into type III resistant starch and maltooligosaccharide molecules

Food processing activities in the potato industry generate potato peel in huge quantities. Potato peel residual biomass is rich in biomolecules with high added value. In the present study, the carbohydrate macromolecule, starch, was extracted from the potato peel, followed by enzymatic debranching by employing type 1 pullulanase, Pul M . The retrogradation of debranched starch resulted in the production of type III resistant starch (RS3). The structural details of the granular and debranched starch samples were investigated by scanning electron microscopy. The yield of about 45% RS3 was achieved from the caloric starch obtained from potato peel. The remaining digestible proportion of the peel starch was used for making the preparation of maltooligosaccharides. The chemical composition of native and resistant starch samples was studied by FTIR. XRD profiling confirmed increased crystallinity of peel starch derived RS3 as compared to the native starch. Furthermore, RS3 exhibited higher thermal stability and remarkable resistance against α -amylase digestion than its native counterpart. The bioprocess developed in the present study can be used as an alternative technology to valorize potato peel into functional bio-products. • Granular starch was extracted from potato peel biomass. • Debranching and retrogradation of peel starch resulted biosynthesis of type III resistant (RS3). • The yield of about 45% RS3 was achieved from the peel starch. • RS3 exhibited increased crystallinity, and higher thermal stability. • RS3 showed remarkable resistance against α -amylase digestion.

Protein content correlates with the in vitro starch digestibility of raw barley flour

Protein content is one of the most important criteria used to evaluate the nutritional and functional qualities of raw barley, yet, its relation with starch digestibility remain elusive. The in vitro starch digestion kinetics of six barley varieties were characterized and correlated with the total protein content, starch chain-length distribution and the particle size distributions (PSD) of raw barley flour. Both the logarithm of slope plot and sequential first-order kinetics model were applied to fit the digestion curves. Results showed that only a single digestible starch fraction was observed for all flour samples under the simultaneous digestion of pancreatic amylase and amyloglucosidase. The barley protein content significantly and negatively correlated with the digestion rate constant k (r = 0.93, p = 0.007), whereas it significantly and positively correlated with the C∞ (r = 0.89, p = 0.017) corresponding to the amount of starch digested at infinite digestion time. No significant correlations between PSD and kinetic parameters were found, whereas of barley containing higher protein content, it contained a relatively higher amount of medium amylopectin chains with degree of polymerization (DP) raging from 34 to 67, and a smaller averaged DP of amylose molecules. This could rationalize its slower starch digestion rate. The current study provides important information for barley breeders and manufacturers to develop barley products with preferred starch functional properties except for only according to the barley protein content.

Surface Removal Enhances the Formation of a Porous Structure in Potato Starch

AbstractNative potato starch exhibits limited susceptibility to enzyme digestion and does not form a porous structure. This study investigates the impact of granule surface on starch susceptibility to amylases. Two levels of surface removal via chemical gelatinization of common corn and potato starches are prepared and subjected to digestion by α‐amylase or glucoamylase. The degree of digestion varies with the surface removal level and starch type. A porous structure is observed in potato starch after combining surface removal and digestion by amylases. However, the pores in the surface‐removed potato starches are not as homogeneous or enlarged compare with corn starch. The removal of dense and tightly packed crystallites on the granule surface is proposed to enhance the degree of binding and hydrolytic activity of both amylases in potato starch. This study provides direct evidence that surface structure hinders amylase digestion and the formation of a porous structure in potato starch.

Effect of α-amylase digestion in fermented Nagara bean grits for gelatinization profile and in vitro starch digestibility

Treatment of α-amylase digestion in wet grits nagara bean after spontaneous fermentation was assessed to determine changes in rehydration ability, gelatinization profile and in vitro starch digestibility of the flour produced. This was important for further processed products that required easy hydration in cold water and high starch digestibility. The research was carried out by hydrolysis of α-amylase with 60 IU enzyme activity as much as 0.1% on wet grits nagara beans from spontaneous fermentation which had been soaked in NaHSO3 and Ca(OH)2 for 1 hour. Moreover, α-amylase digestion was carried out at 37°C for 30, 60 and 90 minutes. The results showed that the amylose content of nagara bean flour from the pre-treatment soaking using Ca(OH)2 was relatively higher than the pre-treatment of NaHSO3, and there was a tendency for amylase digestion up to 90 minutes could reduce amylose and starch content. In vitro starch digestibility of flour by amylase digestion of wet grits nagara bean for 60 minutes with pre-treatment soaked in Ca(OH)2 were 88.79% db, peak viscosity and final viscosity of 2416 cP and 2419 cP respectively.

The Contribution of Different Subunits of Intestinal Mucosal α-glucosidases to the Glucose Release from Starches (P08-090-19)

ObjectivesTo analyze the role of each subunit from Sucrase-Isomaltase (SI) and Maltase-Glucoamylase (MG) on the glucose production from corn starch (NC), Waxy starch (WX) and Hylon V (HLV) starch predigested with pancreatic amylase (Amy). MethodsThe starches were selected based on their ratios of α-1,4 and α-1,6 linkages. Starches were predigested with Amy for 0, 10, 20, 30, 60 and 120 min. After predigestion starches were hydrolyzed with different combinations of recombinant C terminal (C) and N terminal (N) subunits of Sucrase-Isomaltase (SI) and Maltase-Glucoamylase (MG), each at the relative maltase activity of: 40% C-SI, 20% N-SI, 32% C-MG and 8% N-MG, resembling the observed in the human intestinal mucosa. Glucose release was quantified by a real-time glucose oxidase-peroxidase method at 37°C. ResultsC-MG subunit hydrolyzed the three starches without predigestion by Amy at rates of 2.9 ± 0.02, 2.5 ± 0.02 and 2.4 ± 0.05 ng/min of glucose for WX, HLV and NC, respectively. C-SI subunit produced only 0.9 ± 0.02 ng/min glucose from the starches not predigested by Amy. After 30 min of Amy predigestion, the rates of glucose release by C-MG were modified to 13.3 ± 0.09, 12.3 ± 0.08 and 11.6 ± 0.08 ng/min for HLV, NC and WX, respectively. The same predigestion modified glucose release by C-SI subunit to 3.9 ± 0.02, 4.7 ± 0.08 and 5.8 ± 0.03 for WX, NC and HLV, respectively. In starches predigested 60 or 120 min, C-MG subunit alone or together with N-MG showed lower activity than expected, suggesting the occurrence of substrate inhibition. Together the four MG and SI subunits showed clear differences on the rates of glucose production from the starches predigested with Amy for 120 min (22.8 ± 0.133 for WX, 26.4 ± 0.2 for NC and 26.7 ± 0.8 for HLV; all ng/min) which correlated with the glucose production by the N and C SI subunits together (15.5 ± 0.9 for WX, 19.4 ± 0.09 for NC and 23.85 ± 0.12 for HLV; all ng/min). ConclusionsWe found complex interactions among the starch structure, extent of amylase digestion and the rate of glucose release by each C and N subunits of SI and MG. Thus, the rate of intestinal starch digestion depends on the structure of the starches, the predigestion by amylase and, importantly, the relative abundance and catalytic properties of the individual subunits of MG and SI. Funding SourcesConsejo Nacional de Ciencias y Tecnología (CONACyT), Mexico.

The effect of extrusion puffing on the physicochemical properties of brown rice used for saccharification and Chinese rice wine fermentation

Chinese rice wine (CRW), with its high nutritional value and unique flavor, has been popular in China for thousands of years. The traditional steps of immersion and steam cooking during the brewing of rice wine have several drawbacks, including the long production time, large energy consumption, generation of wastewater and the large production area it occupies. Extrusion puffing has the potential to overcome these drawbacks. In this study, the physicochemical properties of extruded-puffed brown rice obtained under different conditions were analyzed. The puffed extrudates exhibited low bulk density, high water solubility index and higher surface area than the steam-cooked brown rice. Extrusion puffing operates at high temperatures, high pressure and provides mechanical shearing forces, resulting in the puffed extrudates having a higher degree of gelatinization, as determined by X-ray diffractometer (XRD), Fourier transform infrared spectroscopy with attenuated total reflection (FTIR-ATR) and differential scanning calorimetry (DSC), revealed the disruption of the native crystalline structure. The effect of extrusion on enzymatic hydrolysis was evaluated using amylase digestion. The results indicated that puffed extrudates significantly improved the enzymatic hydrolysis rate and yield. Moreover, the catalytic efficiency was evaluated by kinetic constants, with extrusion puffing treatment demonstrating an efficiency18-fold higher than steam-cooked brown rice. Finally, extruded-puffed blown rice was used for Chinese rice wine fermentation. The extruded-puffed blown rice improved alcohol yield during the fermentation process, which increased the wine yield by 12.4% compared to traditional cooking methods.

Stabilisation of oil-in-water emulsions with non-chemical modified gelatinised starch

In this research, stabilisation of oil-in-water emulsions with non-chemically modified gelatinised starch is presented. Thus far only octenyl succinic anhydride (OSA) modified gelatinised starch has been known to adsorb at emulsion droplet interfaces, acting as emulsifiers. Screening a range of commercially available food starches revealed that a non-waxy rice starch, a waxy rice starch and the waxy maize starch PRIMA600 showed oil-in-water emulsifying ability following gelatinisation. The microstructure of emulsions formulated with 20% oil and 1% starch was stable for at least 3 months. Thermal, crystallinity and molecular property analyses as well as amylose and protein content revealed no obvious link to this property. Nevertheless, this research has provided the food industry with exciting results for the formulation of clean label emulsions. Moreover, it presents a concept for oral release food emulsions with destabilisation via salivary amylase digestion of the stabilising starch emulsifier.

Inhibition of pancreatic alpha amylase digestion of potato starch by chlorogenic acid in vitro

Inhibition of pancreatic alpha amylase digestion of potato starch by chlorogenic acid <i>in vitro</i>

In vitro amylase digestion of extruded maize and high amylose maize starches and evolution of starch structure

In vitro amylase digestion of extruded maize and high amylose maize starches and evolution of starch structure

Requirements of phytochemical food composition databases: Comparing current use in food industry and biomedical research

Requirements of phytochemical food composition databases: Comparing current use in food industry and biomedical research

Molecular, mesoscopic and microscopic structure evolution during amylase digestion of extruded maize and high amylose maize starches.

Extrusion processing of cereal starch granules with high (>50%) amylose content is a promising approach to create nutritionally desirable resistant starch, i.e. starch that escapes digestion in the small intestine. Whilst high amylose content seems to be required, the structural features responsible for the slow digestion of extrudates are not fully understood. We report the effects of partial enzyme digestion of extruded maize starches on amylopectin branch length profiles, double and single helix contents, crystallinity and lamellar periodicity. Comparing results for three extruded maize starches (27, 57, and 84% apparent amylose) that differ in amylase-sensitivity allows conclusions to be drawn concerning the rate-determining features operating under the digestion conditions used. Enzyme resistance is shown to originate from a combination of molecular and mesoscopic factors, including both recrystallization and an increase in very short branches during the digestion process. This is in contrast to the behaviour of the same starches in the granular form (Shrestha et al., 2012) where molecular and mesoscopic factors are secondary to microscopic structures in determining enzyme susceptibility. Based on the structure of residual material after long-time digestion (>8h), a model for resistant starch from processed high amylose maize starches is proposed based on a fringed micelle structure with lateral aggregation and enzyme susceptibility both limited by attached clusters of branch points.

Mechanism for Starch Granule Ghost Formation Deduced from Structural and Enzyme Digestion Properties

After heating in excess water under little or no shear, starch granules do not dissolve completely but persist as highly swollen fragile forms, commonly termed granule "ghosts". The macromolecular architecture of these ghosts has not been defined, despite their importance in determining characteristic properties of starches. In this study, amylase digestion of isolated granule ghosts from maize and potato starches is used as a probe to study the mechanism of ghost formation, through microstructural, mesoscopic, and molecular scale analyses of structure before and after digestion. Digestion profiles showed that neither integral nor surface proteins/lipids were crucial for control of either ghost digestion or integrity. On the basis of the molecular composition and conformation of enzyme-resistant fractions, it was concluded that the condensed polymeric surface structure of ghost particles is mainly composed of nonordered but entangled amylopectin (and some amylose) molecules, with limited reinforcement through partially ordered enzyme-resistant structures based on amylose (for maize starch; V-type order) or amylopectin (for potato starch; B-type order). The high level of branching and large molecular size of amylopectin is proposed to be the origin for the unusual stability of a solid structure based primarily on temporary entanglements.

Assessing the susceptibility of amylose–lysophosphatidylcholine complexes to amylase by the use of iodine

The formation of amylose–lysophosphatidylcholine (LPC) inclusion complexes renders amylose less susceptible to amylase digestion. In order to better understand this phenomenon on a structural level, the complexation of 9% wheat starch suspensions with 0, 2, 3, and 5% exogenous LPC was developed in RVA. Amylose–LPC inclusion complexes were isolated after 15, 30, 60, 120, and 240 min in vitro digestion of the wheat starch suspensions to quantify the amount of non‐complexed amylose by spectrophotometry. The samples were dissolved in DMSO containing 0.5% LiBr and exposed to iodine. In addition, parts of the digesta were defatted and subjected to the same procedure to elucidate the total amount of amylose that remained undigested. In this way, more insight was obtained into the protective effect of amylose–LPC complex formation on digestion of starch. This study confirms that the amylose susceptibility to amylolysis decreases in the presence of LPC. Higher LPC concentrations not only induced the formation of more amylose inclusion complexes but also resulted in more stable complexes which remained undigested as well as longer amylose chains after enzyme hydrolysis, due to the presence of LPC inside the amylose helix. In addition, a higher melting enthalpy of the amylose–LPC complexes in the digesta demonstrates the protective effect of LPC during enzyme hydrolysis.

The effect of temperature and time on the formation of amylose–lysophosphatidylcholine inclusion complexes

The formation of amylose inclusion complexes could help to decrease the susceptibility of starch granules against amylase digestion. We studied the formation of amylose–lysophosphatidylcholine (LPC) inclusion complexes at temperatures at and below the gelatinization temperature of starch, using DSC, CLSM and SEM. At temperatures below 50°C, only low amounts of complexes were formed; even upon prolonged incubation time (16 h). However, our results show that heating at 50–60°C, for prolonged times, leads to a nearly complete formation of inclusion complexes. Our study therefore indicates that gelatinization is not a prerequisite for inclusion complex formation. Also, the thermal characteristics of the gelatinization peak (onset temperature and enthalpy) are not affected by amylose–LPC complex formation.