• Clean Technology
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• v.29 no.1
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• pp.10-21
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• 2023

Hydrogels that are made of natural polymer-based double networks have excellent biocompatibility, low cytotoxicity, and high water content, assuring that the material has the properties required for a variety of biomedical applications. However, hydrogels also have limitations due to their relatively weak mechanical properties. In this study, hydrogels based on an alginate di-aldehyde (ADA) and gelatin (Gel) double network that is reinforced with additional hydrogen bonds formed between the hydroxyl (-OH) groups of the hyperbranched polymer (HPG) and the functional groups present inside of the hydrogels were successfully synthesized. The enhanced mechanical properties of these synthesized hydrogels were evaluated by varying the amount of HPG added during the hydrogel synthesis from 0 to 25%. In addition, magnetite nanoparticles (Fe₃O₄ NPs) were synthesized within the hydrogels and the structures and the magnetic properties of the hydrogels were also characterized. The hydrogels that contained 15% HPG and Fe₃O₄ NPs exhibited superparamagnetic behaviors with a saturation magnetization value of 3.8 emu g^-1. These particular hydrogels also had strengthened mechanical properties with a maximum compressive stress of 1.1 MPa at a strain of 67.4%. Magnetic hydrogels made with natural polymer-based double networks provide improved mechanical properties and have a significant potential for drug delivery and biomaterial application.

• Journal of Applied Biological Chemistry
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• v.60 no.2
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• pp.179-184
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• 2017

Tolaasin, a 1.9 kDa peptide toxin, is produced by Pseudomonas tolaasii and causes the brown blotch disease of cultivated oyster mushroom. It forms pores on the membrane and thus destroys cellular membrane structure, seriously reducing the productivity of mushroom cultivation. The mechanism of tolaasin-induced cytotoxicity is not known in detail. However, it has been reported to form a pore structure in the cytoplasmic membrane through the molecular multimerization. Therefore, food additives which can interact with tolaasin molecules may inhibit the pore formation by hydrophobic interactions with tolaasin molecules. In this study, various food additive materials have been identified as inhibitors of the tolaasin activity and named tolaasin-inhibitory factors (TIF). Most of TIFs are emulsifying agents for food processing procedures. Among various TIFs, polyglycerol and sucrose esters of fatty acids blocked effectively the cytotoxicity of tolaasins at the concentrations $10^{-4}-10^{-5}M$. These TIFs also successfully suppressed the blotch disease development in the shelf cultivation of oyster mushroom.

• Korean Journal of Food Science and Technology
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• v.30 no.5
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• pp.1114-1119
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• 1998

The stabilities of O/W emulsions (lipophilic core material:lipophobic wall material=3:2, w/w) containing various kinds of emulsifiers were compared to determine the optimal conditions of the HLB (hydrophilic lipophilic balance) value, the concentration and composition of emulsifier, the ratio of core material to the wall material, and the concentration and composition of polymers in the wall material. The effect of different chemical types of emulsifiers and the influence of single vs. binary emulsifier systems were compared with 13 kinds of emulsifier HLB values of $0.6{\sim}16.7$ at the concentration of 0.50%(w/w). The emulsion system was stable (more than 99.0 of ESI value) when the HLB value of the emulsifier was more than 11.0 or less than 2.8 of emulsifier HLB value. But it was unstable (less than 40.0 of ESI value) at the HLB value of the emulsifier between 3.4 and 8.6. Especially, we could find out the emulsion containing the emulsifier of polyglycerol polyricinoleate (PGPR, HLB 0.6) became stable creamy state. And, the ESI value of binary emulsifier system containing 0.25%(w/w) of PGPR and 0.25%(w/w) of polyoxyethylene sorbitan monolaurate (PSML, HLB 16.7) was higher than that of any single emulsifier system at the concentration of 0.50%(w/w). The highest emulsion stability was obtained in the liquefied wall material composed of 0.25%(w/v) of waxy corn starch and 0.50%(w/v) of agar.

• Journal of the Korean Applied Science and Technology
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• v.36 no.2
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• pp.434-447
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• 2019

Polyethylene glycol (PEG) is widely used in cosmetics as a surfactant, detergent and emulsifier. During the manufacturing process, 1,4-dioxane, which is toxic to humans, can be produced as a by-product by dimerization of ethylene oxide. As consumers' interest in cosmetic ingredients has increased, the need for safe emulsion research without PEG ingredients in the personal care market has increased. With increasing consumer interest in cosmetic ingredients, the need for safer emulsion research without the PEG ingredient in the personal care market has increased. In this study, we aimed to develop and stabilize nanoemulsion formulation without PEG. Response Surface Methodology (RSM) was used to develop optimized nanoemulsion formulations. Surfactant content (2~4%), oil content (4~8%) and polyol content (12~24%) were set as independent variables as a result of preliminary experiments for determining independent variables and ranges. The particle size, zeta potential, turbidity, and polydispersity index of the formulation were measured as response variables. As a result of measurement of the prepared nanoemulsion by FIB (Focused ion beam), spherical particles were found to have a size distribution of 100 to 200 nm. The stability of each formulation was evaluated for 30 days at each temperature ($4^{\circ}C$, $25^{\circ}C$, and $45^{\circ}C$). The optimal formulation considering the optimum particle size, turbidity, polydispersity index and zeta potential was found to be surfactant (2%), oil (8%) and polyol (24%).

• Food Engineering Progress
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• v.23 no.2
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• pp.118-124
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• 2019

This study aims to investigate the physical properties of extruded psyllium husk upon the addition of emulsifiers. Three different emulsifiers-glycerol monostearate (GMS), polyglycerol ester (PGE), and sugar ester (SE)-were added to the mixture of psyllium husk and rice powder before extrusion. Extrusion was performed using a twin-screw extruder at 140℃ die temperature, 200 rpm screw speed, and 16% feed moisture content. The physical properties of psyllium husk extrudates including expansion ratio, specific length, piece density, texture profile, color properties, water soluble index, and water absorption index were evaluated. It was observed that the expansion ratio was the highest while the specific length and piece density were the lowest in the control which had no emulsifiers. Texture profile analysis showed that the apparent elastic modulus and breaking strength were highest in the extrudate with a PGE of 0.1%. The adhesiveness was found to be lowest in the extrudates with an SE of 0.1% and GMS of 0.5%. Lightness value was highest in the extrudate with a PGE of 0.1%. Color difference, water soluble index, and water absorption index were highest in the control. The results reveal that some physical properties of extruded psyllium husk were improved with the addition of emulsifiers. This finding provides useful information for the development of psyllium snacks with good physical characteristics.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.4
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• pp.581-587
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• 2003

This study was designed to examine the effect of icroencapsulated iron fortified drink yogurt and vitamin C as a bioavailable helper of iron on chemical and sensory aspects during 20 d storage. Coating material was polyglycerol monostearate (PGMS), and ferric ammonium sulfate and vit C were selected as core materials. The highest efficiency of microencapsulation of iron and vit C were 73% and 95%, respectively, with 5:1:50 ratio (w/w/v) as coating to core material to distilled water. Iron fortification did not affect the fermentation time required for the drink yogurt to reach pH 4.2. The addition of uncapsulated iron decreased the pH during storage. TBA absorbance was significantly lower in capsulated treatments than in uncapsulated treatments during storage. In sensory aspect, the yogurt sample added with uncapsulated iron and vit C, regardless of capsulation, showed a significantly high score of astringency, compared with those of control and other groups. A significantly strong sourness was observed in treatment containing capsulated iron and uncapsulated vitamin C at every time interval. The present study provides evidence that microencapsulation of iron with PGMS is effective for iron fortification in drink yogurt.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.4
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• pp.596-601
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• 2002

The present study was designed to examine the effect of ozone treatment in microencapsulated ${\beta}$-galactosidase on inactivation of the enzyme and sterilization of microorganism. The efficiency was the highest as 78.4% when the ratio of polyglycerol monostearate (PGMS) was 15:1. Activities of lactase remaining outside the capsule were affected by ozone treatment. With the increase of ozone concentration and duration of ozone treatment, the activity reduced significantly. In sensory aspect, with 2% microcapsule addition, no significant difference in sweetness was found compared with a market milk during 12 d storage. Above result indicated that the additional washing process of lactase was not necessary to inactivate the residual enzyme. In a subsequent study, the vegetative cells of microorganisms were completely killed with 10 ppm for 10 min treatment by ozone. The present study provides evidence that ozone treatment can be used as an inactivation and a sterilization process. In addition, these results suggest that acceptable milk products containing lactase microcapsules made by PGMS can be prepared with ozone treatment.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.12
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• pp.1808-1812
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• 2002

The present study was carried out to examine the efficiency of microcapsules and a stability of lactase in vitro in the simulated gastric and intestinal conditions. As a coating materials, medium-chain triacylglycerol (MCT) and polyglycerol monostearate (PGMS) were used. The highest efficiency of microencapsulation was found in the ratio of 15:1 as coating to core material with both MCT (91.5%) and PGMS (75.4%). In a subsequent experiment, lactose content was measured to study a microcapsule stability. Lysis of microcapsules made by MCT in simulated gastric fluid was proportionally increased such as 3% in pH 5 and 11% in pH 2 for 20 min incubation. In the case of PGMS microcapsulation, 11-13% of lactose was hydrolyzed at 20 min in all pHs and also very little amount (less than 3%) of lactose was hydrolyzed after 20 min in all pHs. The highest percentages of lactose hydrolysis in MCT and PGMS microcapsules were 68.8 and 60.8% in pHs 7 and 8 during 60 min, respectively. Based on our data, the lactase microcapsules seemed to be stable when they stay in the stomach, and hydrolyzed rapidly in small intestine where the bile acid was excreted.

• Archives of Pharmacal Research
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• v.26 no.10
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• pp.874-879
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• 2003

The present study was carried out to examine the stability of microencapsulated ascorbic acid in simulated-gastric and intestinal situation in vitro and the effect of microencapsulated ascorbic acid on iron bioavailability. Coating materials used were polyglycerol monostearate (PGMS) and medium-chain triacylglycerol (MCT), and core materials were L-ascorbic acid and ferric ammonium sulfate. When ascorbic acid was microencapsulated by MCT, the release of ascorbic acid was 6.3％ at pH 5 and 1.32％ at pH 2 in simulated-gastric fluids during 60 min. When ascorbic acid was microencapsulated by PGMS, the more ascorbic acid was released in the range of 9.5 to 16.0％. Comparatively, ascorbic acid release increased significantly as 94.7％ and 83.8％ coated by MCT and PGMS, respectively, for 60 min incubation in simulated-intestinal fluid. In the subsequent study, we tested whether ascorbic acid enhanced the iron bioavailability or not. In results, serum iron content and transferring saturation increased dramatically when subjects consumed milks containing both encapsulated iron and encapsulated ascorbic acid, compared with those when consumed uncapsulated iron or encapsulated iron without ascorbic acid. Therefore, the present data indicated that microencapsulated ascorbic acid with both PGMS and MCT were effective means for fortifying ascorbic acid into milk and for enhancing the iron bioavailability.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.2
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• pp.225-231
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• 1994

As the way of mass process of red pepper, extraction of oleoresin, which is labile during distribtuion and long-term storage, is alternative way to minimize markdown of red pepper quality. Changes of carotenoid pigments in modified oleoresin during cooking at high temperature were investigated. Dried red peperwas milled to 100 mesh of size particle and oily compounds were extracted by reduced pressure steam distillation. The rest part was reetracted and concentrated. The extracts were combined . The same volume of water and 4 % of polyglycerol condensed ricinoleate (PGDR) were added to the combined extract, and emulsified to make oleroesin. Capsanthin among dried red pepper, was the most abundant carotenoid (97.80mg%) followed by $\beta$ -cartoene, cryptoxanghin ,violaxanthin, crypotocapsin, and capsorubin. Oleoresin is acquiesce in the same order of raw red pepper. Transmittal of color components from raw red pepper to oleroresin was over 85% in cryptoxanthin, crytocapsin, and $\beta$ -carotene, over 70% in capsolutein and hydroxycapsolutein, and under 50% in antheraxanthin and mutatoxanthi Crytocapsin cryptoxanthin, an capsorubin in oleoresin red pepper were remained 72.1, 51.8 and 25.25, respectively, after cooking for 5hours at10$0^{\circ}C$. Color compounds were unsteady by cooking , About 90% of color compounds were destroyed by 3 hours cooking at 15$0^{\circ}C$. But, they were more thermostable under nitrogen circumstance than air one.