• Proceedings of the SCSK Conference
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• 2003.09b
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• pp.460-461
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• 2003

Clear rinse-off ...gels can be prepared. allowing the introduction of novel product forms. Styling gels with improved viscosity, conditioning. clarity and product aesthetics are also possible with this concept. Beyond the creation of clear product.(omitted)

• Journal of the Korean Chemical Society
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• v.23 no.5
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• pp.320-324
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• 1979

Purple membrane from Halobacterium halobium was incorporated into 7.5% polyacrylamide gels. Absorption and circular dichroic spectra of purple membrane incorporated with gels were obtained at various pH. The spectra of these gels measured at pH 7.0 were essentially identical with those obtained in the aqueous suspension of purple membrane. Acid titration of the gels showed the transition to a form absorbing at 605nm $(bR_{605}^{acid}$) at pH 2.6, and to a second form at 565nm $(bR_{565}^{acid})$ at pH 0.8. Dark-adapted gels showed an isosbestic point for each transition whereas light-adapted gels did not. Visible CD spectra of $bR_{570}^{LA},\;bR_{305}^{acid}\;and\;bR_{565}^{acid}$ all showed the typical bilobed pattern. CD spectra measured at UV wavelength region were also independent of the variation of pH in terms of molar ellipticity and spectral shape. The protonated species $bR_{605}^{acid}$ may be one of the intermediates formed during the normal photochemical cycle of purple membrane. Most probably, the species $bR_{605}^{acid}$ is considered to be $O^{640}$ in the cycle.

• Journal of Microbiology and Biotechnology
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• v.7 no.4
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• pp.267-271
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• 1997

We developed a dermal equivalent (DE) which was engineered using human dermal fibroblasts and a matrix of collagen gel. The in vitro construction of the DE was accomplished by casting a porcine collagen type I solution plus concentrated medium with isolated and cultured fibroblasts. These constructs were attached to culture dishes or left floating in culture medium. Contraction of attached gels results in decreased gel thickness without a change in gel diameter, and contraction of floating gels results in decreased gel thickness and diameter. After contraction, there was no increase in cell number in floating gels, but cells in attached gels began to increase after about 4 days of the lag phase in cell growth curve. At this lag phase, addition of fibroblast growth factor (FGF) at a concentration of $0.1{\mu}$/ml promoted cell proliferation in the attached collagen gels, but no effect in floating gels. These results indicate that the method of contraction had an influence on the extracellular matrix (ECM) organization, and this influenced not only cell growth but also fibroblast responsiveness to FGF. This suggests that attached collagen gel is more suitable as a dermal equivalent than the floating gel. And the final contracted area of attached gel is much larger than that of the floating gel since floating gel is contracted in all directions but attached gel is contracted only vertically.

• Journal of Pharmaceutical Investigation
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• v.28 no.3
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• pp.177-183
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• 1998

Low toxicity, reverse thermal gelation and high drug loading capabilities suggest that poloxamer 407 gels have great potential as a topical drug delivery system. Kojic acid (KA) is an antimelanogenic agent which has been widely used in cosmetics to whiten the skin color. However, it has the drawbacks of skin irritancy due to its acidic pH. Poloxamer gels of different polymer contents were formulated to overcome the problem and compared to the cream type formulations of either w/o/w multiple emulsion cream or o/w type emulsion cream. Using Franz diffusion cells mounted with a synthetic cellulose membrane (MWCO 12,000), drug release characteristics of the formulations were evaluated by the HPLC assay of KA concentration in the receptor compartment of pH 7.4 phosphate buffered saline solutions. Drug release from w/o/w multiple emulsion cream was controlled by oil membrane, showing the apparent zero order release kinetics. The KA release from the poloxamer gels was also controlled by the gel matrix, showing that drug release increased linearly as KA contents increase, but decreased exponentially as the polymer contents increase. In the skin irritancy test, the primary irritancy index(PII) of poloxamer gel base was lower than those of multiple emulsion cream base and o/w cream. Depending on KA contents or polymer contents in the gel. PH values in poloxamer gels were ranged from 1.3 to 2.0, which are interpreted as low or negligible irritation on skin. There was a good correlation between the log value of flux in drug release and PII value in skin irritation. It was possible to conclude that the poloxamer gels containing KA might be a good candidate for an antimelanogenic topical delivery system by virtue of the controlled release of the drug and the reduced skin irritancy.

• Korean Journal of Food Science and Technology
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• v.25 no.6
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• pp.649-654
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• 1993

We investigated the texture of the sweet potato starch gels treated with maltogenic amylase. Effects of branched gluco-oligosaccharides and acorn starch on the texture of the sweet potato starch gel were also investigated. Hardness and cohesiveness of gels were measured by using Instron and sensory evaluation on the gel properties was performed. From the results of the instrumental analysis, it was found that the overall textural properties as Mook could be improved by adding branched glucooligosaccharides, maltogenic amylase or acorn starch to the sweet potato starch gel. As a result, there was a decrease in the cohesiveness of gels while the hardness of gels increased. The sensory evaluation study indicated that the sweet potato starch gels treated with 0.02% maltogenic amylase, or added with 12.5% branched gluco-oligosaccharides, or mixed with 50% acorn starch had preferable quality as Mook.

• Korean Journal of Food Science and Technology
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• v.27 no.6
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• pp.928-933
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• 1995

Sensory and instrumental characteristics of mixed starch gels of defatted corn starch and mung bean starch were examined in terms of the effects of various additives such as textured soy protein(TSP), soybean oil(S0), carboxymethyl cellulose(CMC) and pectin(PC). Gels were prepared by storing the paste at room temperature for 24 hrs and 72 hrs. The additives were used 1% or 2% on the starch basis. The ratio of defatted corn starch and mung bean starch was selected 60 : 40(to, w/w), where the acceptability was the highest. The cohesiveness and springiness of the mixed starch gels stored 24 hrs increased, but the brittleness and acceptability decreased with all the additives. Textural characteristics of the mixed gels stored 72 hrs were different according to the type and content of additives, whereas hardness and cohesiveness increased in all case. Unlike the sensory evaluation, the textural properties of mixed gels tested by a Instron Universal Testing Machine showed no difference in hardness, but the cohesiveness and springiness increased.

• Polymer(Korea)
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• v.39 no.2
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• pp.311-316
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• 2015

Densely structured polyhedral oligomeric silsesquioxane (POSS) was employed as an additive to enhance hardness of silicon-based hybrid gels for LED encapsulants. To improve the miscibility of POSS and polysiloxane resin, alkyl or oligosiloxane branches were introduced to POSS moiety. Platinum-catalyzed hydrosilylation reactions were used to attach branches of 1-decanol, 9-decen-1-ol, and vinyl-terminated oligosiloxane to the POSS molecules. Alkyl-branched POSSs (decyl-POSS and decenyl-POSS) were immiscibile with polysiloxane resin and generated gels with low transparency and low hardness values. On the other hand, oligosiloxane-branched POSS (Siloxy-POSS) showed good miscibility with polysiloxane resin to give gels with high transparency. However, the prepared gels did not show noticeable improvement in hardness compared to the gels without the POSS additive.

• Food Science of Animal Resources
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• v.36 no.5
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• pp.671-678
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• 2016

Fractioning and/or preheating treatment on the rheological properties of myofibrillar protein (MP) gels induced by microbial transglutaminase (MTG) has been reported that they may improve the functional properties. However, the optimum condition was varied depending on the experimental factors. This study was to evaluate the effect of red bean protein isolate (RBPI) on the rheological properties of MP gels mediated by MTG as affected by modifications (fractioning: 7S-globulin of RBPI and/or preheat treatment (pre-heating; 95℃/30 min): pre-heating RBPI or pre-heating/7S-globulin). Cooking yields (CY, %) of MP gels was increased with RBPI (p<0.05), while 7S-globulin decreased the effect of RBPI (p<0.05); however, preheating treatments did not affect the CY (p>0.05). Gel strength of MP was decreased when RBPI or 7S-globulin added, while preheat treatments compensated for the negative effects of those in MP. This effect was entirely reversed by MTG treatment. Although the major band of RBPI disappeared, the preheated 7S globulin band was remained. In scanning electron microscopic (SEM) technique, the appearance of more cross-linked structures were observed when RBPI was prepared with preheating at 95℃ to improve the protein-protein interaction during gel setting of MP mixtures. Thus, the effects of RBPI and 7S-globulin as a substrate, and water and meat binder for MTG-mediated MP gels were confirmed to improve the rheological properties. However, preheat treatment of RBPI should be optimized.

• Journal of the Korean Society of Food Culture
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• v.23 no.4
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• pp.499-506
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• 2008

This study was conducted to determine the quality characteristics of grape jellies for the elderly. The jellies contained sugar (control) or sugar derivative sweeteners (erythritol, isomaltooligosaccharide, sorbitol, and xylitol). Agar (0.31%) and $\kappa$-carrageenan (0.27%) were the gelling agents. The average age of the subjects participating in the acceptance test was 79. The lightness (L), redness (a), and yellowness (b) values of the agar gel with erythritol mostly decreased, indicating a darker and pale red color. The L and b values of the carrageenan gel with sugar derivative sweeteners increased, indicating brighter and yellowish color. The agar and carrageenan gels with sorbitol showed higher gelling and melting temperature, indicating that gelation occurred easily and did not easily melt. The agar and carrageenan gels with xylitol showed a low-melting temperature, indicating low stability with temperature change. The break-down rate of the agar and carrageenan gels with erythritol was low, whereas that of agar gel with sorbitol was relatively high despite its high melting temperature. Hardness, cohesiveness, gumminess, and chewiness of the gels with sugar derivative sweeteners decreased, and this tendency was most distinct with isomaltooligosaccharide in the agar gel and with sorbitol in the carrageenan gel. The rupture properties of the gel were the same as the hardness of the gel. Sensory acceptance of the agar gels with erythritol, sorbitol, isomaltooligosaccharide, and the carrageenan gel with erythritol was fairly high, whereas that of the agar gel with xylitol and the carrageenan gel with isomaltooligosaccharide and xylitol was low. The results show that sorbitol and erythritol are appropriate as sugar substitutes in grape jellies for the elderly about the acceptability and stability of the gels.

• Korean Journal of Food Science and Technology
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• v.28 no.5
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• pp.904-909
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• 1996

To investigate effects of sugars on the retrogradation of rice flour gels, sucrose and isomaltooligosaccharide (1, 2, and 5%, w/w on the flour basis were added to 50% Dongjinbyeo rice flour gels and stored at different temperature $(20^{\circ}C,\;4^{\circ}C)$ far 1, 3 and 6 days. Changes on the degree of retrogradation (DR) of these rice flour gels were measured by α-amylase-iodine method, DSC and X-ray diffractometry. DRs of rice flour gels increased over storage and showed a rapid increase up to 3 days and then decreased thereafter. DRs of rice flour gels with sucrose or oligosaccharide also increased rapidly until 3 day storage but these values were lower than those of rice flour gels without sugar. DRs of rice flour gels with oligosaccharide were lower than those of gels with sucrose. Changes in enthalpy of rice flour gels measured by DSC showed the same tendency with those in DRs of rice flour gels by ${\alpha}-amylase-iodine$ method, but varied with sugar levels.