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Starch enzymatic hydrolysis is a key technology for preparing plant-based dairy alternative beverages, preferred for its low energy consumption, high product yield, and quality. However, the high-temperature requirement to terminate reactions and challenges in continuous operations hinder enzyme applicability. Therefore, encapsulation techniques have been explored to address these limitations, enhancing the enzyme's stability and facilitating process control. This study developed a novel amyloglucosidase encapsulation system based on chitosan-SDS hydrogel capsules produced by simple coacervation. The enzymatic activity of free and immobilised amyloglucosidase was assessed using corn starch and maltose as substrates. The encapsulation process successfully yielded self-supporting structured and spherical capsules, achieving an immobilisation yield of 71% and an enzyme efficiency of 83%. The residual enzymatic activity after 28 days of storage remained at 76%. A feedback inhibition investigation was performed by varying the concentration of corn starch, and favourable applicability of encapsulated amyloglucosidase for continuous processes was found. The encapsulation process offered several advantages, such as a straightforward separation step to halt enzymatic reactions and no need for high temperatures that may affect food product attributes. Lastly, the amyloglucosidase-chitosan-SDS coacervates show promise in improving enzyme stability, facilitating hydrolysis control, and expanding enzyme utilisation in dairy alternative plant beverage manufacture. [ABSTRACT FROM AUTHOR]

This experiment utilised cassava (Manihot utillissima) and arrowroot (Maranta arunadinacea) wastes as the medium of propagation of Saccharomyces cerevisiae to produce β-glucan. The amyloglucosidase hydrolysed the waste, followed by fermentation in the nitrogenous medium by S. cerevisiae. The β-glucan pellet was extracted using 2% NaOH alkaline solution at 90°C for 5 hours, followed by a series of centrifugation processes. The highest glucose concentration from hydrolysis resulted from adding 57.5 mg amyloglucosidase enzyme for arrowroot waste with 95.93% conversion and 50 mg enzyme for cassava waste with 64.70% conversion. The highest amount was obtained for producing S. cerevisiae by adding 4.75 g peptone to all samples. The optimum number of cells was obtained at 1.61 x 108 colonies at t = 48 hours for arrowroot waste and 8.55 x 107 colonies at t = 48 hours for cassava waste. For β-glucan production, the highest number was obtained by using 3.99 g of peptone for cassava waste with a yield of 1.20% and by using 4.75 g of peptone for arrowroot waste with a yield of 1.23%. For β-glucan pellet, the highest number was 1.77 g L-1 (0.18 % b/v) from cassava waste medium and 1.91 g L-1 (0.19% b/v) from arrowroot waste. Mutant cells in the Yeast Extract–Peptone–Glycerol (YPG) medium produced 6.56 g L-1 (0.66% b/v) β-glucan pellet, while wild-type cells in the similar medium produced 1.84 g L-1 (0.18% b/v).

Copyright of Journal of Chinese Institute of Food Science & Technology is the property of Journal of Chinese Institute of Food Science & Technology Periodical Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study describes the enzymatic conversion of oat starch to maltose and glucose under laboratory conditions. First, oat starch is isolated by two different extraction methods (alkali and acid‐alkali). Second, enzymatic starch hydrolysis is carried out for 10% and 12.5% starch solutions obtained by both extraction methods. Third, pullulanase usage together with amyloglucosidase is investigated during saccharification. Finally, effects of the extraction method, starch concentration, and use of pullulanase are evaluated. The use of a 12.5% starch solution obtained by the acid‐alkali method results in higher rates of conversion of starch to glucose and maltose, expressing better substrate for syrup production compared to alkali starch. The use of pullulanase increases the rate of starch conversion to glucose and maltose. The highest conversion of starch to glucose is found to be 49.06% when pullulanase (12 U) is used with amyloglucosidase. The highest dextrose equivalence (DE) value is 97.71, and it is obtained by using pullulanase in 10% ​​acid‐alkali starch. The data obtained in the study show that oat starch can be a suitable source for use in sugar syrup production. The 12.5% starch ​​concentration provides high yield, and the use of pullulanase increases both the amount of hydrolysis products and the DE value. [ABSTRACT FROM AUTHOR]

Summary: Glucose‐rich supernatants were developed based on the enzymatic hydrolysis of raw and extruded chickpea flours first treated with alcalase® and then with a combination of alpha‐amylase and amyloglucosidase or only amyloglucosidase. The optimum treatments were the extruded hydrolysates further treated with amyloglucosidase 'EF(AMG)', or the raw chickpea flour treated with a combination of alpha‐amylase and amyloglucosidase 'RF (Amyl+AMG)'. The resulting supernatants were further fermented with five different strains of Lactobacillus and monitored for 24 h in terms of pH, titratable acidity, and microbial counts. Also, the glucose content and oligosaccharides, total protein, and viability were determined. Both supernatants presented a successful fermentation as estimated by the pH drop (<4.2), lactic acid produced (>0.7%), and microbial counts 9 log (CFU mL−1) which increased up to 5 log during the 24 h fermentation. However, the EF(AMG) supernatant induced fewer reductions in glucose and protein contents in comparison to the RF (Amyl+AMG) counterpart. Among bacteria, the strain Lp 29 in EF(AMG) showed the fastest growth rate (K) and the highest residual protein. In all cases, the proposed technology enhanced the growth of five Lactobacillus strains by taking advantage of the hydrolyzed chickpea chemical composition. [ABSTRACT FROM AUTHOR]

The food enzyme glucan 1,4‐α‐glucosidase (4‐α‐d‐glucan glucohydrolase; EC 3.2.1.3) is produced with the non‐genetically modified Rhizopus arrhizus strain AE‐G by Amano Enzyme Inc. The food enzyme is free from viable cells of the production organism. The applicant proposed the use of the food enzyme in baking processes, coffee processing and manufacture of enzymatically modified dairy ingredients (EMDI). The Panel considered only the baking processes as the relevant intended use of this food enzyme. Dietary exposure to the food enzyme–total organic solids (TOS) was estimated to be up to 0.94 mg TOS/kg body weight (bw) per day in European populations. Genotoxicity tests did not raise a safety concern. The systemic toxicity was assessed by a repeated dose 90‐day oral toxicity study in rats. The Panel identified a no observed adverse effect level of 1,868 mg TOS/kg bw per day, the highest dose tested, which when compared with the estimated dietary exposure, resulted in a margin of exposure of at least 1,987. A search for the similarity of the amino acid sequence of the food enzyme to known allergens was made and one match was found. The Panel considered that under the intended conditions of use the risk of allergic reactions by dietary exposure cannot be excluded, but the likelihood is low. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns when used in baking processes under the intended conditions of use. [ABSTRACT FROM AUTHOR]

The starch in waste bread (WB) from industrial sandwich production was directly converted to ethanol by an amylolytic, ethanologenic thermophile (Parageobacillus thermoglucosidasius strain TM333) under 5 different simultaneous saccharification and fermentation (SSF) regimes. Crude α-amylase from TM333 was used alone or in the presence of amyloglucosidase (AMG), a starch monomerizing enzyme used in industry, with/without prior gelatinisation/liquefaction treatments and P. thermoglucosidasius TM333 fermentation compared with Saccharomyces cerevisiae as a control. Results suggest that TM333 can ferment WB using SSF with yields of 94–100% of theoretical (based on all sugars in WB) in 48 h without the need for AMG addition or any form of heat pre-treatment. This indicates that TM333 can transport and ferment all of the malto-oligosaccharides generated by its α-amylase. In the yeast control experiments, addition of AMG together with the crude α-amylase was necessary for full fermentation over the same time period. This suggests that industrial fermentation of WB starch to bio-ethanol or other products using an enhanced amylolytic P. thermoglucosidasius strain could offer significant cost savings compared to alternatives requiring enzyme supplementation. [ABSTRACT FROM AUTHOR]

The survival rate of mesenchymal stem cells (MSC), a crucial factor in tissue engineering, is highly dependent on glucose supply. The purpose of this paper is to study the potential of starch foams as glucose suppliers. It is investigated through in vitro hydrolysis by amyloglucosidase in conditions that respect physiological constraints (37 °C and pH 7.4), including a duration of 21 days, and no stirring. Nine extruded starch foams with amylose contents ranging from 0 to 74 %, with various cell wall thicknesses (50 to 300 μm), and different crystallinities (0–30 %) were hydrolysed. These kinetics were fitted by a model which shows that the maximum rate of hydrolysis varies from 7 to 100 %, and which allows the rate of hydrolysis at 21 days to be calculated precisely. The results reveal the major role of amylose in glucose delivery kinetics, and the secondary roles of crystallinity and cell wall thickness of the foams. Additional hydrolysis of starch films revealed that thickness positively influences the amylose chain reorganisation during hydrolysis, which, in slows down and limits glucose delivery. A simple glucose delivery kinetics analysis procedure is proposed to select samples for testing as MSC glucose suppliers. [Display omitted] [ABSTRACT FROM AUTHOR]

Starch enzymatic hydrolysis is a key technology for preparing plant-based dairy alternative beverages, preferred for its low energy consumption, high product yield, and quality. However, the high-temperature requirement to terminate reactions and challenges in continuous operations hinder enzyme applicability. Therefore, encapsulation techniques have been explored to address these limitations, enhancing the enzyme’s stability and facilitating process control. This study developed a novel amyloglucosidase encapsulation system based on chitosan-SDS hydrogel capsules produced by simple coacervation. The enzymatic activity of free and immobilised amyloglucosidase was assessed using corn starch and maltose as substrates. The encapsulation process successfully yielded self-supporting structured and spherical capsules, achieving an immobilisation yield of 71% and an enzyme efficiency of 83%. The residual enzymatic activity after 28 days of storage remained at 76%. A feedback inhibition investigation was performed by varying the concentration of corn starch, and favourable applicability of encapsulated amyloglucosidase for continuous processes was found. The encapsulation process offered several advantages, such as a straightforward separation step to halt enzymatic reactions and no need for high temperatures that may affect food product attributes. Lastly, the amyloglucosidase-chitosan-SDS coacervates show promise in improving enzyme stability, facilitating hydrolysis control, and expanding enzyme utilisation in dairy alternative plant beverage manufacture.

Abstract The food enzyme glucan 1,4‐α‐glucosidase (4‐α‐d‐glucan glucohydrolase; EC 3.2.1.3) is produced with the non‐genetically modified Rhizopus arrhizus strain AE‐G by Amano Enzyme Inc. The food enzyme is free from viable cells of the production organism. The applicant proposed the use of the food enzyme in baking processes, coffee processing and manufacture of enzymatically modified dairy ingredients (EMDI). The Panel considered only the baking processes as the relevant intended use of this food enzyme. Dietary exposure to the food enzyme–total organic solids (TOS) was estimated to be up to 0.94 mg TOS/kg body weight (bw) per day in European populations. Genotoxicity tests did not raise a safety concern. The systemic toxicity was assessed by a repeated dose 90‐day oral toxicity study in rats. The Panel identified a no observed adverse effect level of 1,868 mg TOS/kg bw per day, the highest dose tested, which when compared with the estimated dietary exposure, resulted in a margin of exposure of at least 1,987. A search for the similarity of the amino acid sequence of the food enzyme to known allergens was made and one match was found. The Panel considered that under the intended conditions of use the risk of allergic reactions by dietary exposure cannot be excluded, but the likelihood is low. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns when used in baking processes under the intended conditions of use.

Background and Objectives: The main purpose of the present investigation was to evaluate the effects of the commercial enzymes amyloglucosidase, glucose oxidase, and transglutaminase on the technological quality of a gluten‐free bread based on cornstarch, rice flour, and buckwheat flour. Gluten‐free bread was analyzed for baking loss, bread central slice height, specific volume, textural properties, porosity, and pore size. Findings: Glucose oxidase and transglutaminase provided the lowest values of baking loss (7.16% and 6.38%, respectively) compared with the control (8.56%). Amyloglucosidase resulted in bread with specific volume three times greater (2.55 ml/g) than the control (0.9 ml/g). Transglutaminase provided a 73% decrease in crumb chewiness compared with the control and resulted in bread with small pores. Conclusion: The application of 15 g/kg of flour amyloglucosidase, 7.5 g/kg of flour glucose oxidase, and 0.25 g/100 kg of flour transglutaminase improved the overall technological quality of the developed gluten‐free bread. Significance and Novelty: The results obtained showed that industrial enzymes can improve the technological quality—texture and crumb parameters—of a gluten‐free bread made from a complete formulation containing food additives, and buckwheat flour as a protein source. [ABSTRACT FROM AUTHOR]

The inhibitory mechanisms of rice glutelin amyloid fibril aggregates (RAFA) against amylolytic enzymes (α-amylase and amyloglucosidase) were examined by enzyme kinetic analysis, fluorescence quenching, and molecular dynamics (MD) simulations. The results of kinetic studies revealed that 2 h-RAFA exhibited anticompetitive inhibition against α-amylase, while both 6 h-RAFA and 10 h-RAFA demonstrated competitive inhibition. For amyloglucosidase, different RAFA both exhibited competitive inhibition. In fluorescence spectroscopy analysis, RAFA led to a decrease in fluorescence intensity and a red-shift in the maximum emission wavelengths of amylolytic enzymes, suggesting evident interactions between RAFA and the enzymes. Furthermore, the MD simulations further indicated that RAFA bound to specific amino acid residues near the active site of α-amylase through hydrogen bonding, electrostatic interactions, and hydrophobic interactions. This interaction resulted in a modified microenvironment surrounding the Tyr residue in the enzyme's structure, ultimately leading to inhibited enzyme activity. In the case of amyloglucosidase, RAFA was observed to bind primarily to the catalytic structural domain of the enzyme via hydrogen bonding and hydrophobic interactions, effectively blocking the substrate's access and, consequently, diminishing enzyme activity. In summary, this study establishes a theoretical foundation for understanding the mechanisms by which RAFA inhibits starch digestion. [Display omitted] • RAFA exhibited anticompetitive or competitive inhibition on α-amylase. • RAFA exhibited competitive inhibition on amyloglucosidase. • Amylolytic enzyme fluorescence was quenched by the addition of RAFA. • MD simulations elucidated the interactions between RAFA and amylolytic enzymes. • The study helps reveal the inhibitory mechanism of RAFA on starch digestion. [ABSTRACT FROM AUTHOR]

[Display omitted] • Food waste (FW) could be used as complete medium for astaxanthin fermentation. • The different fermentation strategies of astaxanthin from FW were compared. • Mechanism of astaxanthin production in the direct fermentation were investigated. • FW showed potential for low-cost industrial production of astaxanthin. Bioconversion of food waste (FW) into value-added products is a promising approach to solve FW management problem and achieve the global goal of carbon peak and carbon neutralization. In this study, FW could be used as a complete medium to compare the effects of four different fermentation strategies on direct astaxanthin fermentation by Phaffia rhodozyma. The carotenoid production by direct fermentation (DF) reached 129.5 mg/L, increasing by 61.3 %, compared with separate hydrolysis and fermentation (SHF), and carotenoid production by simultaneous saccharification fermentation (SSF) and 1 h pre-hydrolysis SSF (PSSF) were only 20.2 % and 21.5 % higher than DF, respectively. The mechanism of astaxanthin production in the DF could be attributed to the utilization of rice starch due to the production of amylase, and the stimulation of cell growth resulted from the metal elements and the lipid of soybean oil in FW. Remarkably, a 70.3 % increase of carotenoid production was observed when substrate loading increased from 10 % to 20 %. The present study provides a novel process for astaxanthin production from direct bioconversion of FW by P. rhodozyma , which shows potential for low-cost industrial production of astaxanthin. [ABSTRACT FROM AUTHOR]

The courses of starch digestion with individual α-amylase (AA), amyloglucosidase (AMG), and AA/AMG bi-enzyme system were performed and analyzed by first-order-reaction equations in the absence and presence of tannic acid (TA). An antagonistic effect between AA and AMG occurred at the digestion phase of readily-digestible starch due to the higher catalytic efficiency of AMG for starchy-substrates with more complex structures. This effect caused a faster rate of glucose production with AMG than with AA/AMG bi-enzyme system at this phase both in the absence and presence of TA. TA had a higher binding affinity to AA than to AMG as accessed by several methods, such as inhibition kinetics, fluorescence quenching, isothermal titration calorimetry (ITC), and molecular docking. Besides, differential scanning calorimetry (DSC) indicated that the change in the thermal and structural stabilities of enzymes in the presence of TA was related to the enzyme residues involved in binding with TA, rather than the inhibitory effects of TA. The binding characters of TA to both enzymes resulted in more “free” AMG without TA binding in AA/AMG bi-enzyme system than that in individual AMG. This binding property caused more and faster rate of glucose production at the digestion phase of slowly digestible starch (SDS) in the bi-enzyme system.

[Display omitted] • An efficient process of 6-bOcta-AA-2G without using pyridine was established. • The efficient production process by CGTase with soluble starch and amyloglucoaidase. • The yield by this process was about 3-times higher than that by the previous process. • This process is superior to the previous process in terms of efficiency and cost. 2- O -α- d- Glucopyranosyl-6- O -(2-propylpentanoyl)- l -ascorbic acid (6-bOcta-AA-2G) has shown a remarkable antitumor effect in an in vivo study. However, an efficient and low-cost process for synthesis of 6-bOcta-AA-2G has not been established yet. The process used for synthesis of 6-bOcta-AA-2G in this study consisted of three steps. The first step was acylation of l -ascorbic acid (AA) at the C-6 position with 2-propylpentanoic acid in concentrated H 2 SO 4 at room temperature for 24 h to obtain 6- O -(2-propylpentanoyl)- l -ascorbic acid (6-bOcta-AA). Next, specific glycosylation of 6-bOcta-AA at the C-2 position by cyclodextrin glucanotransferase (CGTase) from Thermoanaerobacter sp. was carried out using soluble starch as a low-cost glycosyl donor in acetate buffer (pH 6.0) at 40 °C for 24 h. In this glycosylation reaction by CGTase, oligoglucosylated 6-bOcta-AAs seemed to be generated, and thus these oligoglucosides were further hydrolyzed by amyloglucosidase from Rhizopus sp. at 40 °C for 1 h in the reaction mixture containing CGTase to efficiently obtain 6-bOcta-AA-2G. The overall yield of 6-bOcta-AA-2G was 19.4 %. The presented synthetic process can be used for mass production of 6-bOcta-AA-2G as an antitumor agent. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The physicochemical properties, organic acid, and phenolic profiles of hawthorn wines prepared by different pretreatments were analyzed. It was found that fermentation together with smashed seeds was favorable for ethanol production, while thermal maceration, addition of pectinase and amyloglucosidase significantly increased the levels of sugar-free extract, residual sugar, total phenolics, flavonoids, and most individual phenolic comounds, showing beneficial effects on improving nutritive value of hawthorn wine. Addition of pectinase and amyloglucosidase caused an increase of methanol content by 34.88% and 26.97%, respectively, while thermal maceration decrease the methanol content by 36.20%. Addition of amyloglucosidase yielded the highest contents of procyanidins as well as flavanols, while thermal maceration and addition of pectinase were favorable for improving phenolic acid level. All the pretreatments significantly increased the contents of succinic acid and malic acid in the final wines, among which thermal maceration and addition of pectinase yielded the highest content of succinic acid and malic acid respectively.

Sweet sorghum is currently being evaluated throughout the world as a raw material for biofuel production because its stem juices are rich in sugars that can be directly fermented to ethanol. In this work, the fermentative efficiency of three sweet sorghum genotypes was evaluated, aiming at ethanol production, harvested in two seasons, clean and whole stems, and the treatment of the juice and broth with amylolytic enzymes in order to use the present starch to increase the production of ethanol. The experiment was carried out in the 2013/2014 harvest, in the municipality of Jaboticabal, São Paulo, Brasil, located at 21°14’05’’S and 48°17’09’’W. The experimental design was completely randomized, with sub-subdivided plots and four replications. The primary treatments were the sweet sorghum genotypes (CV147, CV198, and BRS508), the secondary treatments, the type of harvest (whole stems and clean stems); the tertiary the two sampling times (102 and 116 days after sowing - d.a.s) and the quaternary the application of enzymes. In the fermentation process, the yeast PE-2 was used, at the end, the wine was recovered and characterized. Fermentation efficiency and liters of ethanol per ton of sorghum were calculated. The clarification of the juice with enzymatic treatment increases the quality of the fermentation broth and makes it possible to obtain wines with lower levels of RRTs and Brix. Fermentation efficiency is not affected by the genotype; however, it is influenced by the time of harvest and the technological quality of the juice. The use of amylolytic enzymes makes it possible to obtain wines with lower levels of RRTS and Brix. The best period of industrialization was at 102 d.a.s., and the processing of whole stalks resulted in less ethanol production.

Kitchen waste (KW) production is anticipated to rise because of accelerated urban and economic growth, particularly in Asian nations. Therefore, applications/recycling of KW should be explored for its effective utilization to generate a sustainable source of energy that will ultimately avoid massive economic and energy losses. The main goal of this study was to investigate the combinational effect of thermochemical and enzymatic pre-treatment on synthetic KW to enhance the release of fermentable sugars for the synthesis of value-added products such as polyhydroxyalkanoates (PHAs). The thermochemical pre-treatment of KW samples was performed using 4 N HCl, 4 N H 2 SO 4 , and 4 N NaOH at a concentration of 0–30% (v/v), 30–100 °C for 0–120 min. Furthermore, to enhance the total fermentable sugars, variable enzyme dosages were added after acidic or alkaline pre-treatments (0–1% v/v α-amylase and 0–1% v/v amyloglucosidase-AMG) while maintaining a constant pH 5, temperature 50 °C, and time 30 min. Pre-treatment of KW with acid (15% v/v 4 N HCl in water) at temperature 100 °C, followed by enzymatic hydrolysis, i.e., 0.6% (v/v) α-amylase and 0.4% (v/v) amyloglucosidase (at pH 5, 50 0C and 60 min) resulted in the maximum concentration of fermentable reducing sugars (46.13 g/L) in the hydrolysate. • The food and fuel conflict can be resolved using KW for valuable product synthesis. • This research contributes to an improved comprehension of PHA production using KW. • Combined thermochemical and enzymatic pre-treatment maximized the reducing sugars. • The fermenting bacteria SSC0ST can simultaneously uptake all the reducing sugars. • PHA content in biomass reached 31.15% w/w with PHA concentration of up to 3.06 g/L. [ABSTRACT FROM AUTHOR]

Currently, comes up the need to develop and produce modified starches that allow enhancing their applicability as additives in food industry. In this, the effect of biocatalysis time and type of drying (forced convection and vacuum drying) on the morphological, structural and pasting properties of enzymatically modified cassava starch granules was evaluated. The application of amyloglucosidase generated a degree of hydrolysis ranging between 35.87 and 41.02% equivalents of dextrose (ED), in addition, it caused significant changes in starch granules morphology. At structural level, modified starch reveals substantial changes with respect to control, where FT-IR spectra show the displacement of absorption bands by tension or bending in the region between 900 and 1100 cm-1 due to the breakdown of α-D-glucosidic bonds α-D-(1,4) or α-D-(1,6), increasing swelling, absorption and solubility in water properties. Likewise, significant changes are reported in pasting properties together with an increase in stability in techno-functional properties of hydrolyzed starches dried in vacuum.

• Amyloglucosidase and glucose isomerase have been used to produce fructose syrup. • Their immobilization permit the combined use of the enzymes. • The addition of Mg2+ prevent negative effects of Ca2+. • As one biocatalyst is magnetic, it can be separated from the other biocatalyst. • They could be reused for six consecutive cycles without significant activity decrease. High fructose syrup is a sweetener widely used as a substitute for sucrose in the food and beverage industry with its current industrial production being carried out in three sequential processes using three different enzymes that operate under different pH and temperature conditions. In this study, a single step synergistic saccharification and isomerization process has been proposed, using the commercial amyloglucosidase from Aspergillus niger immobilized by the CLEA technique (co-aggregated with magnetic nanoparticles and polyethyleneimine), and the commercial immobilized glucose isomerase (IGI) from Streptomyces murinus , Sweetzyme® IT Extra. Immobilization stabilized both enzymes, widening the operation window, thus, by applying a factorial design with a central composite rotatable design it was possible to define an optimal condition of pH and temperature of the process, as well as the best ratio between the two enzymes (pH 5.7, 50 °C and U GI /U AMG ratio of 1.56). Simultaneous saccharification and isomerization of 35 % (w/v) dextrin solution produced a Dextrose Equivalent yield over 95 %, with a glucose-to-fructose conversion around 48 % after 30 h of reaction. In addition, both biocatalysts could be reused for six consecutive cycles, maintaining glucose-to-fructose conversions without loss of activity and with easy recovery of the biocatalysts. Furthermore, because they are of different natures (magnetic CLEA of amyloglucosidase and non-magnetic IGI pellets), if one of these biocatalysts is inactivated, they can be easily separated and reloaded individually. [ABSTRACT FROM AUTHOR]

Fucoidan refers to a group of sulfated polysaccharide that is commonly obtained from various species of brown seaweed. Fucoidan has gained increased popularity among researchers in the recent years due to its numerous biological activities, including its inhibitory effects against starch hydrolyzing enzymes such as α-amylase and α-glucosidase. This highlights the potential of fucoidan as an antidiabetic agent in the management and prevention of diabetes mellitus. In this study, the inhibitory effects of fucoidan isolated from the New Zealand Undaria pinnatifida seaweed species against three starch hydrolyzing enzymes—α-amylase, α-glucosidase, and amyloglucosidase—was investigated. It was demonstrated that while the fucoidan exhibited significant inhibitory effects against all the three starch hydrolases, it is an uncompetitive inhibitor of α-amylase and amyloglucosidase, and is a competitive inhibitor of α-glucosidase. Moreover, it exhibited significantly stronger inhibitory effects against α-glucosidase than α-amylase, thus having the desirable characteristics as an antidiabetic agent.

Abstract The food enzyme glucoamylase (4‐α‐D‐glucan glucohydrolase; EC 3.2.1.3) is produced with the genetically modified Trichoderma reesei strain DP‐Nzh38 by Danisco US Inc. The genetic modifications do not give rise to safety concerns. The food enzyme is free from viable cells of the production organism and its DNA. The food enzyme is intended to be used in distilled alcohol production, starch processing for glucose syrup production, baking and brewing processes. Since residual amounts of total organic solids (TOS) are removed by distillation and by purification steps applied during the production of glucose syrups, consequently, dietary exposure was not calculated for these uses. Based on the maximum use levels recommended for baking and brewing processes and individual data from the EFSA Comprehensive European Food Consumption Database, dietary exposure to the food enzyme–TOS was estimated to be up to 5.8749 mg TOS/kg body weight per day. The toxicity studies were carried out with another glucoamylase from T. reesei (strain DP‐Nzh49) considered by the Panel as a suitable substitute. Genotoxicity tests did not raise safety concern. The systemic toxicity was assessed by means of a repeated dose 90‐day oral toxicity study in rats. The Panel identified no observed adverse effect level (NOAEL) at the highest dose tested of 1,149 mg TOS/kg body weight (bw) per day resulting in a margin of exposure of at least 195. Similarity of the amino acid sequence to those of known allergens was searched for and one match was found. The Panel considered that, under the intended conditions of use, the risk of allergic sensitisation and elicitation reactions by dietary exposure cannot be excluded, but the likelihood for this to occur is considered to be low. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use.

Abstract This study aimed to purify and characterize amyloglucosidase (AMG) from Leohumicola incrustata. AMG was purified to homogeneity from cell-free culture filtrate of an ERM fungus grown in a modified Melin–Norkrans liquid medium. The molecular mass of the AMG was estimated to be 101 kDa by combining the results of Sephadex G-100 gel filtration, sodium dodecyl sulphate–polyacrylamide gel electrophoresis, and zymography. The K m and k cat values were 0.38 mg mL−1 and 70 s−1, respectively, using soluble starch as a substrate. The enzyme was stable at 45 °C (pH 5.0), retaining over 65% activity after a pre-incubation period of 24 h. The metal inhibition profile of the AMG showed that Mn2+ and Ca2+ enhanced activity, while it was stable to metals ions, except a few (Al3+, Co2+, Hg2+ and Cd2+) that were inhibitory at a concentration higher than 5 mM. Thin layer chromatography revealed that only glucose was produced as the product of starch hydrolysis. The amylase from L. incrustata is a glucoamylase with promising characteristics such as temperature stability over an extended period, high substrate affinity and stability to a range of chemicals. Also, this study reports for the first time the possibility of using some culturable ERM fungi to produce enzymes for the bio-economy.

Fucoidan refers to a group of sulfated polysaccharide that is commonly obtained from various species of brown seaweed. Fucoidan has gained increased popularity among researchers in the recent years due to its numerous biological activities, including its inhibitory effects against starch hydrolyzing enzymes such as α-amylase and α-glucosidase. This highlights the potential of fucoidan as an antidiabetic agent in the management and prevention of diabetes mellitus. In this study, the inhibitory effects of fucoidan isolated from the New Zealand Undaria pinnatifida seaweed species against three starch hydrolyzing enzymes—α-amylase, α-glucosidase, and amyloglucosidase—was investigated. It was demonstrated that while the fucoidan exhibited significant inhibitory effects against all the three starch hydrolases, it is an uncompetitive inhibitor of α-amylase and amyloglucosidase, and is a competitive inhibitor of α-glucosidase. Moreover, it exhibited significantly stronger inhibitory effects against α-glucosidase than α-amylase, thus having the desirable characteristics as an antidiabetic agent. [ABSTRACT FROM AUTHOR]

This study evaluated the effect of enzymatic hydrolysis on malt bagasse for fermentative sugar extraction in thermostatic and ultrasonic bath. The enzymatic reaction was performed using cellulase, α‐amylase, and amyloglucosidase (in separate and combined) on malt bagasse to analyze the hydrolysis effect. For this, a central composite rotational design was applied to evaluate the effect of solid:liquid (malt bagasse w/v) versus enzymatic concentration, considering cellulase, α‐amylase, and amyloglucosidase enzymes in mix solution, on fermentable sugars liberation. Then the kinetic fermentative sugars liberation was evaluated in a hydrolysis reaction using cellulase, α‐amylase, and amyloglucosidase (in separate and combined) after exposure in thermostatic and ultrasonic bath. From enzymatic mix, the maximum total reducing sugar (TRS) yield was 408.8 and 219.9 mg·g−1 in thermostatic and in ultrasound bath, respectively. Kinetic studies showed a TRS variation of 6 to 7 g·L−1 for all enzymes. Amyloglucosidase was more promising in assimilation of malt bagasse, responsible for 43% of sugar releasing. Briefly, a low‐cost procedure using thermostatic bath improved the hydrolysis reaction. The results from the experiments present a new application where malt bagasse can be employed showing the potential of this brewing industry residue in fomenting processes, as bioethanol production. [ABSTRACT FROM AUTHOR]

The food enzyme glucoamylase (4‐α‐D‐glucan glucohydrolase; EC 3.2.1.3) is produced with the genetically modified Trichoderma reesei strain DP‐Nzh38 by Danisco US Inc. The genetic modifications do not give rise to safety concerns. The food enzyme is free from viable cells of the production organism and its DNA. The food enzyme is intended to be used in distilled alcohol production, starch processing for glucose syrup production, baking and brewing processes. Since residual amounts of total organic solids (TOS) are removed by distillation and by purification steps applied during the production of glucose syrups, consequently, dietary exposure was not calculated for these uses. Based on the maximum use levels recommended for baking and brewing processes and individual data from the EFSA Comprehensive European Food Consumption Database, dietary exposure to the food enzyme–TOS was estimated to be up to 5.8749 mg TOS/kg body weight per day. The toxicity studies were carried out with another glucoamylase from T. reesei (strain DP‐Nzh49) considered by the Panel as a suitable substitute. Genotoxicity tests did not raise safety concern. The systemic toxicity was assessed by means of a repeated dose 90‐day oral toxicity study in rats. The Panel identified no observed adverse effect level (NOAEL) at the highest dose tested of 1,149 mg TOS/kg body weight (bw) per day resulting in a margin of exposure of at least 195. Similarity of the amino acid sequence to those of known allergens was searched for and one match was found. The Panel considered that, under the intended conditions of use, the risk of allergic sensitisation and elicitation reactions by dietary exposure cannot be excluded, but the likelihood for this to occur is considered to be low. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use. [ABSTRACT FROM AUTHOR]

Amyloglucosidase catalyses the hydrolysisof glycosidic residues from non-reducing ends of amylose and amylopectin in starch components to produce ß-D-glucose for industrial processes. The utilization of composite agro-substrates for amyloglucosidase production byAspergillus niger OTF and A. flavus CLOR1 using solid state fermentation and characterization of the enzyme were investigated. The substrates include rice bran (R), soybeans flour (S), palm kernel cake (P), wheat bran (W) and oyster shell (O) at various compositions (Medium I - VIII) were supplied with adequate moisture content for a solid culture medium of fermentation. They were inoculated into with the isolates and incubated at 30 °C for 120 h respectively. Cultural conditions such as temperature, pH and storage stability were optimized. Medium I (WSPO; 100:2:3:1, w/w) yielded amyloglucosidase activity 83.92 Ug-1and Medium V (WSP; 100:2:3, w/w) resulted into activity 67.64 Ug-1 at 48 h optimal time. There was decline in activity after 48 h in all samples but with maximum activity at pH 5. Aspergillus niger OTF showed maximum amyloglucosidase activity23.5 Ug-1 as compared with A. flavus CLOR1 20.07 Ug-1 at 30 °C. The residual activities in term of storage stability were 43.9% and 44.9% at 4 °C and 68. 6% and 27.8% at 28 °C at week 2 respectively which later declined over a period of time. This study revealed that higher glucoamylase activity was significantly enhanced using these inexpensive and readily available agro-residues by both strains of isolates in solid culture medium. Thus, these residues could be a potential and economic source for the production of amyloglucosidase. [ABSTRACT FROM AUTHOR]

Surface modifications of starch provide benefits in various applications for food and medical products as a carrier material due to their high adsorption ability. The effect of enzymatic and acid modification of starch surfaces on the morphology and characteristics of granular tapioca starch is investigated. Tapioca starch slurry is prepared and treated with α‐amylase (αA), amyloglucosidase (AM), the combination of these two enzymes (αA+AM), and 2.2 m HCl (AS) at various hydrolysis times. Starch granular surface of αA, AM, and αA+AM‐treated samples show voids and cavities. The AS sample induced more surface roughness in the granules as compared to the enzyme‐treated samples and some parts of the granules are smaller or fused together into a larger size. The highest relative crystallinity is obtained from the AS samples (48.43%). All modified samples exhibit an increase in their specific surface area, volume of pores, and average diameter. The AM sample shows the highest specific surface area (1.66 m2 g−1) which corresponds to the largest pore volume (0.38 cm3 g−1) while the AS sample shows the highest average diameter (21.87 nm). Overall, a modified granular starch surface with various characteristics can be provided by using hydrolysis enzymes and acid. [ABSTRACT FROM AUTHOR]

This study is based on two aims firstly, the project is to develop a relation bridge between academic and industry personnel and secondly, in this study, we have evaluated the amount of α-amylase and amyloglucosidase required for effective saccharification of parboiled rice of 18 mesh size. The reason behind the selection of broken rice was its costeffectiveness as well as waste utilization. Another reason behind the selection of broken rice as raw material was its utilization in the industry is on a large scale. The maltodextrin production rate by α-amylase and characterization of α- amylase was also a part of the study. Three unit ratios of α-amylase and amyloglucosidase were chosen i.e. 2:2, 4:4, 6:6. The maximum yield of 85.13 % maltodextrin was obtained by saccharification with a ratio of 6:6 units of α- amylase and amyloglucosidase after 30 minutes of saccharification. The 53.52 % yield of maltodextrin was obtained with 4ml of α-amylase (concentration 1mg/ml) at 120 minutes when α-amylase act alone on rice gelatinized starch. The determined kinetic parameters for α-amylase were Vmax- 33,333 s-1, Km- 446.66 M. The activity of α-amylase was found as 358.15 IU/mg. The kinetic model developed to predict the time perspective maltodextrin production was fitted well. The coefficient of determination (R2) found as0.996 for experimental and predicted values of maltodextrin. [ABSTRACT FROM AUTHOR]

The physicochemical properties, organic acid, and phenolic profiles of hawthorn wines prepared by different pretreatments were analyzed. It was found that fermentation together with smashed seeds was favorable for ethanol production, while thermal maceration, addition of pectinase and amyloglucosidase significantly increased the levels of sugar-free extract, residual sugar, total phenolics, flavonoids, and most individual phenolic comounds, showing beneficial effects on improving nutritive value of hawthorn wine. Addition of pectinase and amyloglucosidase caused an increase of methanol content by 34.88% and 26.97%, respectively, while thermal maceration decrease the methanol content by 36.20%. Addition of amyloglucosidase yielded the highest contents of procyanidins as well as flavanols, while thermal maceration and addition of pectinase were favorable for improving phenolic acid level. All the pretreatments significantly increased the contents of succinic acid and malic acid in the final wines, among which thermal maceration and addition of pectinase yielded the highest content of succinic acid and malic acid respectively. [ABSTRACT FROM AUTHOR]

• ANAG was covalently immobilized on AFAC with 100% efficiency. • Immobilized ANAG's initial activity was retained after 20 use and 20 days storage. • Maltodextrin was completely converted to glucose by using immobilized ANAG. • Immobilized ANAG obtained can be used in industrial production of glucose syrup. This study was aimed the covalently immobilization of Aspergillus niger amyloglucosidase (ANAG) onto activated carbon (AC) obtained from sesame seed shell. AC was firstly functionalized with ethylenediamine, and after then activated with glutaraldehyde. 99.80% immobilization yield and 99.83% activity yield were obtained as the result of optimization of immobilization conditions (pH and molarity of immobilization buffer, AC amount, and reaction time). The optimum pH (5.5) and the optimum temperature range (55–60 °C) for ANAG were not affected by immobilization. After immobilization, Vmax value decreased from 1464.1 μmol D-glucose/L.min to 1342.3 μmol D-glucose/L.min, while Km value decreased from 116.3 g maltodextrin/L to 109.9 g maltodextrin/L. The immobilized enzyme retained 99.30% and 98.30% of its initial activity, respectively after twenty repeated uses and after twenty days of storage in 5 mL sodium phosphate buffer (0.1 M, pH 5.5) at +4 °C in a refrigerator. Finally, glucose syrup was produced from maltodextrin solution having 1% (w/v) concentration by using the immobilized ANAG. Maltodextrin was completely converted to glucose after four hours. Consequently, it can be said that the immobilized ANAG obtained in this study can be used in the industrial production of glucose syrup. [ABSTRACT FROM AUTHOR]

Starch is a technologically challenging polysaccharide that arouses the global interest in its modification to increase its applicability. Thus, the objective of the present work was to study the influence of enzymatic modification on the properties of red rice starch. The enzymatic modification was performed sequentially through the actions of α-amylase enzymes and amyloglucosidase using a design of experiments where several process conditions were used at sub-gelatinization temperatures. Then the native and modified starches were characterized for its physicochemical, physical, centesimal, phytochemical, morphological, and thermal properties. The enzymatic hydrolysis of the starch granules with α-amylase resulted in 4.46% hydrolysis and more 8.63% after the action amyloglucosidase. Results revealed that surface adsorption is more limiting than diffusion. The enzymatic hydrolysis process resulted in a reduction of the amylase and amylopectin content, as well as on all phytochemicals. After hydrolysis, granules starches presented surface alterations and tendency to become spherical. Small differences on crystallinity revealed that the enzymes had more influence on the amorphous fractions of the starch granules. • Un-treated red rice starch was sequentially hydrolyzed using a-amylase and then amyloglucosidase. • Enzyme adsorption revealed to be the limiting step of the hydrolysis process. • Starch granules surface and geometry were altered after both hydrolysis. • Minor changes on gelatinization temperature and crystallinity suggest that the hydrolysis occurred on the amorphous fraction. [ABSTRACT FROM AUTHOR]

An investigation on purification and characterization of amyloglucosidase enzyme from Endomycopsis fibuligera by fermentation of sago starch has been carried out. This enzyme is inductive and can be produced by fermenting sago starch in a medium containing E. fibuligera. Crude enzyme was obtained by centrifuging the medium cultures containing E. fibuligera at 6,000 rpm for 20 min and then adding with 0.15 M acetate buffer (pH 5.0). Enzyme activity was determined using Somogyi-Nelson method by quantifying the released glucose from amyloglucosidase catalysis of starch (0.2%) as substrate. Prepurification process was conducted by ammonium sulphate fractionation and it showed that the ammonium sulphate fractionation with the degree of saturation of 40-60% produced a maximum activity of enzyme. Purification by DEAE-Cellulose and Sephadex G-75 column chromatography produced three and one fractions with purifity 17.4 and 22.5 times, respectively, compared to the crude extract enzyme. Characterization of this enzyme showed the optimum condition at pH 5.0 and 55 °C with 0.2% starch as substrate. The amyloglucosidase activities was strongly increased by addition of Co2+ and Mn2+ ions, whereas the activities were weakly decreased by addition of K+, Mg2+, and Fe3+ ions.

Currently, comes up the need to develop and produce modified starches that allow enhancing their applicability as additives in food industry. In this, the effect of biocatalysis time and type of drying (forced convection and vacuum drying) on the morphological, structural and pasting properties of enzymatically modified cassava starch granules was evaluated. The application of amyloglucosidase generated a degree of hydrolysis ranging between 35.87 and 41.02% dextrose equivalents (ED), in addition, it caused significant changes in starch granules morphology. At structural level, modified starch reveals substantial changes with respect to control, where FT-IR spectra show the displacement of absorption bands by tension or bending in the region between 900 and 1100 cm-1 due to the breakdown of a-Dglucosidic bonds a-D-(1,4) or a-D-(1,6), increasing swelling, absorption and solubility in water properties. Likewise, significant changes are reported in pasting properties together with an increase in stability in techno-functional properties of hydrolyzed starches dried by vacuum. Actualmente surge la necesidad desarrollar y producir almidones modificados que permitan potenciar su aplicabilidad como aditivos en la industria alimentaria. En este se evaluó el efecto del tiempo de biocatálisis y tipo de secado (convección forzada y secado a vacío) sobre las propiedades morfológicas, estructurales y de empastamiento de gránulos de almidón de yuca modificados enzimáticamente. La aplicación de la amiloglucosidasa generó un grado de hidrólisis que oscila entre 35.87 y 41.02 % equivalentes de dextrosa (ED), además, provocó cambios significativos en la morfología de los gránulos de almidón. A nivel estructural, el almidón modificado revela cambios sustanciales con respecto al control, donde los espectros de FT-IR muestran el desplazamiento de bandas de absorción por tensión o flexión en la región entre 900 a 1100 cm-1 debido al rompimiento de uniones glucosídicas a-D-(1,4) o α-D-(1,6), aumentando las propiedades de hinchamiento, absorción y solubilidad en agua. Asimismo, se reportan cambios significativos en las propiedades de empastamiento junto con un incremento de estabilidad en las propiedades tecnofuncionales de los almidones hidrolizados secados a vacío. [ABSTRACT FROM AUTHOR]

Highlights • The influence of ultrasound in the activity of amyloglucosidase was evaluated. • Six commercially-available amyloglucosidases were tested. • A Box-Behnken response surface methodology established the optimum conditions for each enzyme. • The role of US in the amlyloglucosidase-assisted hydrolysis of pure starch (corn, rice, potato, wheat) was investigated. Abstract The present report studied the role of ultrasound (US) energy in the amyloglucosidase-based starch hydrolysis using two complementary approaches: (i) in the activity of six commercially-available amyloglucosidases (using soluble starch as substrate), and (ii) in the hydrolysis of four pure starches from different botanical sources. This corresponds to the first systematic evaluation of the role of US in starch hydrolysis mediated by amyloglucosidase, being a consequence of our previous report that assessed the effect of US in the activity of alpha-amylase (LWT – Food Science and Technology 84 (2017) 674–685). Regarding amlyloglucosidases, three enzymes obtained from Aspergillus niger (AN1-AN3), and Spirizyme Achieve (SPA), Spirizyme Fuel (SPF) and Spirizyme Ultra (SPU) were submitted to a Box-Behnken experimental design in order to establish the optimum conditions for their maximum activity. In the presence of US, we found both inactivation and activation, ranging from -88% (AN3) to 699% (SPA). The US promoted the enzyme activity when combined with lower temperatures (40–60 °C), with a marked effect in Spirizyme enzymes. Based on the optimum conditions established by the experimental design, we also evaluated the role of US in the glucose yield resulting from the hydrolysis of pure starches (corn, rice, potato, wheat). In this case, US led to higher glucose yields in all conditions tested. The enhancement factors observed ranged from 1.2 (AN1, rice starch) to 65 (SPA, potato starch) times. We compared these findings with previous reports, which highlighted the role of US in intensifying amyloglucosidase-based saccharification in mild conditions, by simultaneously influencing both enzyme and substrate. Hence, US power has to be fine-tuned for each particular enzyme in order to maximize process intensification. [ABSTRACT FROM AUTHOR]

Galactooligosaccharides are added to infant formula to simulate some of the benefits associated with human milk oligosaccharides, in particular to modulate the gut microbiota. During our study the galactooligosaccharide content of an industrial GOS ingredient was determined by differential enzymatic digestion using amyloglucosidase and β-galactosidase. The resulting digests were fluorophore labeled and analyzed by capillary gel electrophoresis with laser induced fluorescence detection. Quantification of the results were based on a lactose calibration curve. Utilizing this approach, the galactooligosaccharide concentration of the sample was determined as 37.23 g/100 g, very similar to earlier HPLC results, but requiring only 20 min separation time. The CGE-LIF method in conjunction with the differential enzymatic digestion protocol demonstrated in this paper offers a rapid and easy to use method to measure galactooligosaccharides and should be applicable to the determination of GOS in infant formulas and other products. • Galactooligosaccharide content of an industrial GOS ingredient was determined. • Differential enzymatic digestion was used with amyloglucosidase and β-galactosidase. • The resulting digests were fluorophore labeled and analyzed by CE-LIF. • Quantification of the results were based on a lactose calibration. • Method applicable to determine GOS in infant and adult formulas. [ABSTRACT FROM AUTHOR]

Abstract The food enzyme glucoamylase (glucan 1,4‐α‐glucosidase; EC 3.2.1.3) is produced with the genetically modified strain of Aspergillus niger by Novozymes A/S. The genetic modifications do not give rise to safety concerns. The food enzyme is free from viable cells of the production organism and recombinant DNA. This glucoamylase is intended to be used in brewing processes and in starch processing for glucose syrups production. Residual amounts of total organic solids (TOS) are removed by the purification steps applied during the production of glucose syrups, consequently dietary exposure was not calculated. For brewing processes, based on the proposed maximum use levels, dietary exposure to the food enzyme–TOS was estimated to be below 3.627 mg TOS/kg body weight (bw) per day in European populations. Genotoxicity tests did not raise a safety concern. The systemic toxicity was assessed by means of a repeated dose 90‐day oral toxicity study in rodents. The Panel identified a no‐observed‐adverse‐effect level (NOAEL) at the highest dose of 1,360 mg TOS/kg bw per day. Similarity of the amino acid sequence to those of known allergens was searched and one match was found. The Panel considered that, under the intended condition of use, the risk of allergic sensitisation and elicitation reactions upon dietary exposure to this food enzyme cannot be excluded, but the likelihood of such reactions to occur is considered to be low. Based on the data provided, the removal of TOS during the production of glucose syrups and the derived margin of exposure for brewing processes, the Panel concluded that this food enzyme does not raise safety concerns under the intended conditions of use.

Industrial processing factors, such as temperature, compromise the viability of probiotic cells. Objective was to develop a system to thermally stabilize probiotic bacteria based on porous starches and using biopolymers as coating materials (gelatinized starch, guar gum and xanthan gum). Porous starches from corn and rice starches, having controlled number and size of porous were used as supporting material. Scanning electron microscopy confirmed the adsorption of the microorganism, leading microcapsules with corn starch but aggregates with rice starch. Surface pores of rice starch increased the encapsulation yield of rice starch around 10%, but that effect was not observed in porous corn starch. The highest encapsulation yield was obtained with porous starches coated with gelatinized starch, which ranged from 92 to 100%. Microencapsulates made with porous starches with small pores, like the ones obtained with α-amylase, and coated with gelatinized starch resulted in the highest thermal resistance at 55 °C. [ABSTRACT FROM AUTHOR]

Preparation of poly[ethylene glycol dimethacrylate (EGDMA)-glycidyl methacrylate (GMA)] cryogel and its usability for amyloglucosidase adsorption were investigated. Cryogels were prepared by cryocopolymerization technique and then functionalized by lectin concanavalin A (Con A). The synthesized cryogel was characterized by FTIR, SEM and EDX analysis and then used for adsorption of amyloglucosidase in a continuous flow system. The maximal amyloglucosidase adsorption efficiency of Con A attached cryogel was found to be as 30.50 mg/g cryogel. Con A modified cryogels were used repeatedly for 30 times without any significant decrease at the amyloglucosidase adsorption capacity. SDS-PAGE and activity studies confirmed that the desorbed amyloglucosidase was active and retained 90% of its initial activity after the adsorption/desorption processes. [ABSTRACT FROM AUTHOR]

Aim of the present study is to estimate glycemic carbohydrates and develop data base on glycemic index and glycemic load (GI and GL) of commonly consumed cereals and legumes by using Food and Agriculture Organization (FAO) or World Health Organization (WHO) methods. The results of glycemic carbohydrates in rice was 79.22 %, wheat 63.26 % and pulses in the range from 51.24 % (green gram) to 56.22 %, (chana dhal), mixed dhal 40.09 %, wheat + chana dhal (60:40) 49.94 %, wheat + chana dhal + barley (40:30:30) was 46.89 %, respectively. The results of GI and GL of rice were the highest (GI-78.23, GL-49.38), followed by wheat chapatti (GI-65.66, GL-32.83). The pulses tested were showing lower values ranging from (GI-37.95 to 43.01 and GL-18.97 to 21.50), mixed dhal (GI-43.64, GL-21.82), wheat + chana dhal (60: 40) (GI-32.37, GL-16.18), wheat + chana dhal + barley (40:30:30) GI-39.27, GL-19.63, respectively. The results of the study indicated that pulses have low glycemic indices and glycemic loads, hence, could be safely used in the diet of diabetic patients. [ABSTRACT FROM AUTHOR]

The effects of the molecular structures of amylopectins on the enzymatic hydrolysis of waxy-rice amylopectin (WRA) and normal-rice amylopectin (NRA) were investigated. The results indicated that compared to NRA, WRA possessed larger chain length, number of chains, internal chain length, degree of polymerisation, interblock chain length, and lower degree of branching and short:long B-chains, which caused WRA was much less susceptible to enzymatic hydrolysis than NRA. The digestibility curves for WRA and NRA were well fitted by the first-order kinetic equation. WRA and NRA were hydrolyzed in two separates phases in the LOS plots. Whether using α-amylase alone, or together with amyloglucosidase, WRA and NRA exhibited different digestibility rates due to different chain structure of amylopectin. The low C 1∞ values predicted that WRA and NRA would have little impact on blood glucose concentrations in the early digestion stage. HPLC results showed that G1 ∼ G5 from WRA using α-amylase were lower than that from NRA, whereas from WRA were higher than that from NRA. There was the synergism between α-amylase and amyloglucosidase in glucose released from WRA and NRA. [ABSTRACT FROM AUTHOR]

It were performed two experiments to evaluate the utilization of industrial enzymes in the evaluation of NDF contents in high-starch materials. In the first experiment, it was verified the accuracy of estimates of neutral detergent fiber (NDF) obtained with the utilization of three industrial enzymes (Termamyl 2X, Liquozyme Supra 2.2.X, and Amylase AG 300L) at different volumes (50, 100, 250 or 500 mL/ sample). Samples were simulated to contain starch at 0, 100, 300, 500 and 1000 g/kg using purified cellulose and starch (n = 240). In the second experiment, samples of corn grain and sorghum grain were evaluated considering the same enzyme types and volumes used in the first experiment adding aliquots without using enzyme (n = 104). There was no significant bias of NDF recovery for simulated samples containing starch up to 300 g/kg. Considering those samples, none difference among enzymes was observed. It was observed a more intense decrease in NDF content according to each enzyme unit added on corn when compared to sorghum. Considering NDF evaluation in samples with mass of 0.7 to 1.0 g, it can be recommended the utilization of 250 mL the ?-amylases Termamyl and 2X Liquozyme 2.2X with activities of 240 and 300 KNU/g, respectively.

The purpose of the present study is to improve the endothelial progenitor cells (EPC) activation, proliferation, and angiogenesis using enzyme-aided extraction of fucoidan by amyloglucosidase (EAEF-AMG). Enzyme-aided extraction of fucoidan by AMG (EAEF-AMG) significantly increased EPC proliferation by reducing the reactive oxygen species (ROS) and decreasing apoptosis. Notably, EAEF-AMG treated EPCs repressed the colocalization of TSC2/LAMP1 and promoted perinuclear localization of mTOR/LAMP1 and mTOR/Rheb. Moreover, EAEF-AMG enhanced EPC functionalities, including tube formation, cell migration, and wound healing via regulation of AKT/Rheb signaling. Our data provided cell priming protocols to enhance therapeutic applications of EPCs using bioactive compounds for the treatment of CVD.

Background: Wet methods of 1-3, 1-4 -β-D-glucan isolation from cereals differ mainly in the type of grain fraction used as raw material, the solid-liquid ratio of β-glucan in raw material vs. solvent used, and the type of aqueous solvent modification (alkali, neutral or acidic). All these factors impact the characterization of the residues finally found in extracts. Oat bran is a rich source of globulin fraction which can be transferred into the extracts, especially when a high pH is employed. Methods: A multi-stage (enzymatic and acidic) purification procedure was performed to remove the residues, especially starch and protein, from β-glucan isolates from oat of different molar mass. Pancreatin, thermostable α-amylase, amyloglucosidase, and papain were used for consecutive residue removal. Three levels of low pH = 4.5, 3.5 and 3.0 were also tested for effective protein precipitation. Results: The starch hydrolysis and liquefaction significantly facilitate the proteinaceous matter removal although papain usage showed an intensive unfavorable impact on β-glucan molar mass. Soluble protein content was significantly decreased after pancreatin and α-amylase treatment, while the significant reduction of amine nitrogen was noted after complete starch hydrolysis and a second acidification step. Conclusions: A complex procedure employing different enzymes is needed to successfully reduce the possibly bioactive residues in isolated oat β-glucan fractions.

Porous starches might offer an attractive alternative as bio-adsorbents of a variety of compounds. However, morphology and physicochemical properties of starches must be understood before exploring their applications. Objective was to study the action of different amylolytic enzymes for producing porous starches. Wheat, rice, potato and cassava starches were treated with Amyloglucosidase (AMG), α-amylase (AM) and cyclodextrin-glycosyltransferase (CGTase). Morphological characteristics, chemical composition, adsorptive capacity and pasting/thermal properties were assessed. Scanning Electron Microscopy (SEM) showed porous structures with diverse pore size distribution, which was dependent on the enzyme type and starch source, but no differences were observed in the total granule surface occupied by pores. The adsorptive capacity analysis revealed that modified starches had high water absorptive capacity and showed different oil adsorptive capacity depending on the enzyme type. Amylose content analysis revealed different hydrolysis pattern of the amylases, suggesting that AMG mainly affected crystalline region meanwhile AM and CGTase attacked amorphous area. A heatmap illustrated the diverse pasting properties of the different porous starches, which also showed significant different thermal properties, with different behavior between cereal and tuber starches. Therefore, it is possible to modulate the properties of starches through the use of different enzymes. [ABSTRACT FROM AUTHOR]

Slowly digestible starch (SDS) offers a range of health benefits due to its stabilizing and sustaining effect on blood glucose. Contributors to the slow digestion property of certain starches include their specific structure and their interaction with factors that inhibit effective digestion. In this study, the effects of tea polyphenols (TPLs) on the enzyme activities of pancreatic a-amylase and amyloglucosidase, which are used during starch digestion, were investigated by an in vitro Englyst test. Our results showed that TPLs noncompetitively inhibit the activity of pancreatic a-amylase (pH 6.9) but activate amyloglucosidase (pH 4.6) in a dose-dependent manner. However, when the two enzymes were employed together under the Englyst test condition at pH 5.2, a heterogeneous inhibition pattern was observed with a peak inhibition of ~30% when the TPL content was ~2.5 mg/mL, and a negative inhibition pattern when TPL content was greater than 4 mg/mL. In contrast, a similar degree of starch digestibility was observed in the presence of TPLs, which indicates that a modification of the Englyst assay warrants further studies to reflect the in vivo starch-digestion patterns, where a slower digestion of starch was observed in the presence of TPLs, which is corroborated by in vivo studies from the literature. [ABSTRACT FROM AUTHOR]