Publications by authors named "Yong-Ro Kim"

Unlabelled: The effectiveness of the rice flour blends (RFB) for improving the processing suitability of Dodamssal rice flour (DD), a functional rice variety with a relatively high amylose and resistance starch content, was investigated. Physicochemical properties and freeze-thaw stability of RFB composed of DD and four rice flour (RF) samples with different amylose contents were measured at different DD ratios. DD, which has low swelling power and low pasting viscosity properties, has improved some quality in terms of physicochemical properties by blending with other RF.

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The phenolic compounds (PCs) abundant in fruits and vegetables are easily browned by oxygen and browning enzymes, with subsequent destruction of nutrients during food processing and storage. Therefore, natural anti-browning additives are required to control these reactions. The aim of the present study was to investigate the feasibility of cycloamylose (CA) complexation as a way to improve stability of PCs against oxidation and browning enzymes.

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Recently, health-conscious consumers have a tendency to avoid the use of modified starch in their food products because of reluctance regarding food additives or chemical processes. The present paper considers the characteristics and manufacturing methods of clean label starch, which is free from chemical modification. Clean label starch manufacturing is mainly dependent on starch blending, physical and enzymatic modification methods.

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In this study, 4-α-glucanotransferase (4αGTase)-treated rice starch (GS) was added after 1-h (1 GS) and 96-h (96 GS) treatments to the aqueous phase of a curcumin-loaded emulsion to produce filled hydrogels (1 GS-FH and 96 GS-FH, respectively). The relative protective effects of the FH system, native rice starch-based filled hydrogel (RS-FH), and emulsion without starch (EM), on curcumin were evaluated based on ultraviolet (UV) stability and simulated gastrointestinal studies. The UV stability and curcumin retention after in vitro digestion of the filled hydrogels (FH) samples were greater than those of the EM samples.

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Rosemary extract (RE) has significant antioxidant and antibacterial properties; however, the application of RE to areas with an aqueous solution is limited due to its poor solubility. There is a need for research focused on finding a method to improve water solubility for incorporating RE into aqueous systems, such as food and cosmetic. Therefore, in this study, the micellar solubilization of RE is conducted using four types of surfactants (Tween 20, polyglyceryl-10-laurate, polyglyceryl-10-myristate, and polyglyceryl-10-monooleate) to increase the water solubility of RE and the effects of various surfactant types and concentration on solubility were investigated.

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Of all the active compounds in rosemary extract, carnosic acid (CaA) has the most potent antimicrobial and antioxidant activity; however, its low solubility limits its applications. We developed complexing systems using cycloamylose (CA), branched dextrin (BD), and β-cyclodextrin (βCD) to improve the solubility of CaA and compared it to the use of maltodextrin (MD). The complexes formed with CA, BD, βCD, and MD improved the water solubility of CaA by as much as 2.

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This study was performed to examine the stability of retinol contained within oil-in-water (O/W) emulsions under UV and during storage at different temperatures. O/W emulsions were prepared using different emulsifiers and oil concentrations. The stability of the retinol contained in the O/W emulsions was investigated by measuring the percentage of residual retinol in the samples after UV exposure and storage at different temperatures (4, 25, and 40 °C).

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A 4-α-glucanotransferases from (TTαGT) possesses an extra substrate binding site, leading to facile purification of the intact enzyme using amylose as an insoluble binding matrix. Due to the cost of amylose and low recovery yield, starch was replaced for amylose as an alternative capturer in this study. Using gelatinized corn starch at pH 9 with 36-h incubation in the presence of 1 M ammonium sulfate increased the TTαGT-starch complex formation yield from 2 to 56%.

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Xylobiose consists of two molecules of xylose and has been highly recognized as a food supplement because it possesses high prebiotic functions. β-xylosidase exhibits enzymatic activity to hydrolyze xylobiose, and the enzyme can also catalyze the reverse reaction in the presence of high concentrations of xylose. Previously, β-xylosidase from Bacillus pumilus IPO (BpXynB), belonging to GH family 43, was employed to produce xylobiose from xylose.

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The aim of this study was to examine the effects of xanthan gum on the lipid digestibility, rheological properties, and β-carotene bioaccessibility of rice starch-based filled hydrogels. β-Carotene was solubilized within lipid droplets of emulsion that were then entrapped within rice starch hydrogels fabricated with different concentrations of xanthan gum. At a low concentration of xanthan gum (<0.

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The complex formation capability of cycloamylose (CA), having a degree of polymerization of 23-45, with phenolic compounds (PCs) was investigated using various physicochemical techniques. The fluorescence intensity of PCs increased and then reached a plateau at 10-20mM cyclodextrin, while it continued to increase at up to 60mM CA. Thermodynamic data of CA complexes with PCs revealed that the binding process was primarily enthalpy-driven and spontaneous.

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An optimal reaction condition for producing cycloamylose (CA) from sweet potato starch was investigated using a combination of isoamylase (from sp.) and 4-α-glucanotransferase (from , TAαGT). Starch was debranched by isoamylase for 8 h and subsequently reacted with TAαGT for 12 h.

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A whey protein isolate-rhodamine B conjugate (WPI-RB) was synthesized to visualize changes in the location of a protein emulsifier in oil-in-water emulsions during digestion. An oil-soluble dye (Nile Red) was used to visualize changes in the lipid phase during digestion. Protein-labeled and lipid-labeled emulsions were passed through a simulated gastrointestinal tract consisting of mouth, stomach, and intestinal phases, and changes in protein and lipid location and morphology were monitored using confocal laser scanning microscopy.

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There is considerable interest in controlling the gastrointestinal fate of nutraceuticals to improve their efficacy. In this study, the influence of methylcellulose (an indigestible polysaccharide) on lipid digestion and β-carotene bioaccessibility was determined. The carotenoids were encapsulated within lipid droplets that were then loaded into rice starch hydrogels containing different methylcellulose levels.

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Low-fat spreads were developed using a thermoreversible gelling agent, the 4-α-glucanotransferase (4αGT)-modified rice starch. The low-fat spreads consisted of the modified starch paste (or rice starch or maltodextrin), olive oil (0-30% w/w), egg yolk, salt, xanthan gum, and butter flavor, and were produced by homogenization, ultrasonic processing at 50% amplitude for 2min, and cold-gel setting at 4°C for 24h. Formulations with 15% and 20% of the modified starch paste resulted in highly stable oil-in-water low-fat spreads having varied textural properties and acceptable spreadability, whereas formulations with rice starch and maltodextrin did not yield enough stability and consistency.

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β-Carotene was incorporated into three types of delivery system: (i) "emulsions": protein-coated fat droplets dispersed in water; (ii) "hydrogels": rice starch gels; and (iii) "filled hydrogels": protein-coated fat droplets dispersed in rice starch gels. Fat droplets in filled hydrogels were stable in simulated mouth and stomach conditions, but aggregated under small intestinal conditions. Fat droplets in emulsions aggregated under oral, gastric, and intestinal conditions.

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A gel-based encapsulation system was developed by incorporating W/O/W emulsions and 4-α-glucanotransferase (4αGTase) treated starch capable of thermoreversible gel formation, and its physical and release characteristics were investigated as functions of preparation conditions and temperature. Release properties of the W/O/W gels were affected by stability and encapsulation efficiency (EE) of W/O/W emulsions embedded within. Lower EE caused by longer sonication time increased fast release dye portion, which resulted in higher dye release rate, even though emulsion stability improved at longer sonication time.

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The physicochemical properties of 4-α-glucanotransferase (4αGTase)-modified rice flours were examined by measuring the molecular weight distribution, moisture sorption isotherm, and melting enthalpy of ice crystals. The results obtained by measuring the moisture sorption isotherm and melting enthalpy of ice crystals revealed that 4αGTase-modified rice flours had high water binding capacity than that of control rice flour. When the textural properties of noodles containing 4αGTase-treated rice flours after freeze-thaw cycling were measured by texture profile analysis, the textural properties of control noodle deteriorated.

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The present study was performed to investigate the stability of W/O/W emulsions containing 4-α-glucanotransferase (4αGTase)-treated starch against environmental stresses such as heating, shearing, and repeated freeze-thawing. W/O/W emulsions were subjected to thermal processing at different temperatures ranging from 30 to 90 °C for 30 min, constant shear for 0-7 min, and freeze-thaw cycling between -20 °C and 30 °C, respectively, and followed by encapsulation efficiency (EE) measurement. As for the case of thermal stress, it was clearly shown that addition of 4αGTase-treated starch in the internal aqueous phase of emulsions helped to maintain higher EE during thermal processing.

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To develop a novel ibuprofen-loaded solid dispersion with enhanced bioavailability using cycloamylose, it was prepared using spray-drying techniques with cycloamylose at a weight ratio of 1:1. The effect of cycloamylose on aqueous solubility of ibuprofen was investigated. The physicochemical properties of solid dispersions were investigated using scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and X-ray diffraction.

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The present study was performed to investigate the possibility of using 4-α-glucanotransferase (4αGTase)-treated starch in W/O/W emulsions to increase their encapsulation efficiency (EE) and stability. Emulsions were prepared using soybean oil, polyglycerol polyricinoleate (PGPR), 4αGTase-treated starch and Tween 20. The mean diameter of W/O/W droplets ranged from 4 to 10μm depending on the sonication time.

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To investigate the hypocholesterolemic mechanism of barley in vivo, six-week-old C57BL/6J mice were fed a high-fat diet (HFD) or high-fat diet containing barley (HFD-B) for seven weeks. Total and LDL cholesterol concentrations were significantly reduced in the HFD-B group while fecal cholesterol and bile acid was increased. Real-time PCR and immunoblot analysis revealed the induction of FXR expression, which in turn suppressed the expression of ASBT and NPC1L1 in the HFD-B group compared with the controls.

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The effect of cycloamylose on the aqueous solubility of flurbiprofen was investigated. To improve the solubility and bioavailability of flurbiprofen (poor water solubility), a solid dispersion was spray dried with a solution of flurbiprofen and cycloamylose at a weight ratio of 1:1. The physicochemical properties of solid dispersions were investigated using SEM, DSC, and X-ray diffraction.

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Scope: Enzymatically modified rice starch (ERS) synthesized with 4-α-glucanotransferase has a longer structure than rice starch, which could delay digestion, similar to dietary fiber. We investigated the effects of ERS on glucose and lipid metabolism with mice fed a high-fat diet containing ERS (HFD-ERS).

Method And Results: Four weeks of ERS feeding showed hypoglycemic effects with a significant reduction in fasting glucose (46%), insulin (57%), and leptin (83%) levels; improved glucose tolerance (20% in AUC of oral glucose tolerance test); and increased adiponectin concentrations (+27%) compared to the HFD group.

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In this study we tried to prepare stable water-in-oil-in-water (W/O/W) emulsions using polyglycerol polyricinoleate (PGPR) as a hydrophobic emulsifier and whey protein isolate (WPI) as a hydrophilic emulsifier. At first, water-in-oil (W/O) emulsions was prepared, and then 40 wt% of this W/O emulsion was homogenized with 60 wt% aqueous solution of different WPI contents (2, 4, and 6 wt% WPI) using a high-pressure homogenizer (14 and 22 MPa) to produce W/O/W emulsions. The mean size of final W/O/W droplets ranged from 3.

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