• Fisheries and Aquatic Sciences
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• 제17권3호
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• pp.299-304
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• 2014

The objective of this study was to elucidate the physicochemical characteristics of gelatin extracted from jellyfish Rhopilema hispidum. We investigated the proximate composition, amino acids, gel strength, gelling/melting points, dynamic viscoelastic properties, and viscosity of jellyfish gelatin. Jellyfish gelatin contained 12.2% moisture, 1.5% lipid, 2.1% ash, and 84.8% protein. Glycine, hydroxyproline, proline, and alanine were the predominant amino acids. The gelatin showed a gel strength of 31.2 kPa, a gelling point of $18.0^{\circ}C$, and melting point of $22.3^{\circ}C$. The gelatin was composed of ${\alpha}_1$-chain, ${\alpha}_2$-chain, ${\beta}$-chain, and ${\gamma}$-chain. During cooling and heating process, jellyfish gelatin showed lower elastic modulus (G') and loss modulus (G") values than mammalian gelatin. Jellyfish gelatin did not show superior rheological properties to mammalian gelatin, like other fish gelatin; however, it can be used in various food and cosmetic products not requiring high gel strength.

• 한국지반공학회논문집
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• 제26권9호
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• pp.47-58
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• 2010

본 논문에서는 2.0 Shot 방식의 최적 주입비를 산정하고 이에 대한 주입시간과 강도에 대한 검증을 실시하였다. 따라서 본 연구를 수행하기 위하여 유제거동 지배방정식을 이용하여 최적 주입비를 산정하고 이에 대한 실내실험과 현장실험을 실시하였다. 실내실험은 주입비의 변화에 따른 주입시간의 비교, 재령과 공극비의 변화에 따른 강도 특성을 예측하기 위한 호모겔과 샌드겔의 강도실험으로 구분하여 실시하였다. 연구결과 2.0 Shot 방식의 최적 주입비는 1:2 일 경우 침투가 가장 효율적으로 나타났다. 강도 실험에서도 다른 주입비에 비해 최적 주입비가 큰 강도를 발현하는 것으로 나타났다. 또한 현장실험을 통하여 현장에서도 높은 강도가 발현될 것으로 판단된다.

• Asian-Australasian Journal of Animal Sciences
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• 제29권6호
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• pp.845-854
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• 2016

Characteristics and properties of gelatin from goat skin pretreated with NaOH solutions (0.50 and 0.75 M) for various times (1 to 4 days) were investigated. All gelatins contained ${\alpha}$-chains as the predominant component, followed by ${\beta}$-chain. Gelling and melting temperatures of those gelatins were $23.02^{\circ}C$ to $24.16^{\circ}C$ and $33.07^{\circ}C$ to $34.51^{\circ}C$, respectively. Gel strength of gelatins increased as NaOH concentration and pretreatment time increased (p<0.05). Pretreatment for a longer time yielded gelatin with a decrease in $L^*$-value but an increase in $b^*$-value. Pretreatment of goat skin using 0.75 M NaOH for 2 days rendered the highest yield (15.95%, wet weight basis) as well as high gel strength (222.42 g), which was higher than bovine gelatin (199.15 g). Gelatin obtained had the imino acid content of 226 residues/1,000 residues and the gelatin gel had a fine and ordered structure. Therefore, goat skin gelatin could be used as a potential replacer of commercial gelatin.

• Restorative Dentistry and Endodontics
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• 제29권3호
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• pp.219-225
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• 2004

This study evaluated the microshear bond strength of composte resin to teeth bleached with commercial whitening strips and compared with those bleached with home bleaching gel. Twelve extracted human central incisors were cut into pieces and central four segments were chosen from each tooth and embedded in acrylic resin. Four blocks with 12 tooth segments embedded in acrylic resin were acquired and numbered from group one to group four. Group 1 was bleached with Crest Whitestrips, group 2 with Claren, group 3 with Opalescence tooth whitening gel (10％ carbamide peroxide). Group 4 was used as control. The bleaching procedure was conducted for 14 days according to the manufacturer's instructions ; the bleaching strips twice a day for 30 min and the bleaching gel once a day for 2hr. After bleaching, composite resin (Filtek Supreme) was bonded to the enamel surfaces with a self-etching adhesive (Adper Prompt L-Pop) using Tygon tube. Microshear bond strength was tested with a universal testing machine (EZ-test). The data were statistically analysed by one-way ANOVA. The study resulted in no statistical differences in microshear bond strength between the tooth segments bleached with 2 different whitening strips and bleaching gel. It can be concluded that the effect of bleaching with either commercial whitening strips or bleaching gel on enamel is minimal in bonding with self-etching adhesive to composite resin.

• 한국축산식품학회지
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• 제43권6호
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• pp.1031-1043
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• 2023

The purpose of this study was to investigate the functional properties of salt-soluble proteins obtained from Protaetia brevitarsis (PB) and Tenebrio molitor (TM) larvae, the interaction between these proteins and pork myofibrillar protein (MP) in a gel system. The gel properties of salt-soluble protein extracts showed that the PB had a higher viscosity than the TM protein. However, the TM protein had higher gel strength compared with the PB protein. The gelation characteristics of the pork MP gel systems added with lyophilized insect salt-soluble protein powder showed to decrease slightly viscosity compared with MP alone. Adding the TM or PB protein powder did not affect the pork MP's hydrophobicity and sulfhydryl group levels. Furthermore, the protein bands of the MP did not change with the type or amount of insect salt-soluble protein. The cooking yields of the pork MP gels containing PB or TM protein powder were higher than those without insect protein. Regardless of the type of insect salt-soluble protein added, the pork MP's gel strength decreased. Furthermore, as the level of insect powder increased, the surface protein structure became rough and porous. The results demonstrated that proteins extracted from PB and TM larvae interfered with the gelation of pork MP in a gel system.

• 약학회지
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• 제42권3호
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• pp.290-295
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• 1998

To optimize the formulation of acetaminophen liquid suppository, the effect of additives on the physicochemical properties of liquid suppository base was investigated. The physi cochemical properties of P 407/P 188 (15/15%) (abbreviated in 15/15) and P 407/P l88 (15/20%) (abbreviated in 15/20) were measured after the addition of following additives; 2.5% acetaminophen as an active ingredient, vehicle components (5% ethanol, 5% propylene glycol, 5% glycerin), preservatives (0.1% sodium benzoate, 0,1% methylparahydroxybenzoate, 0.1% propylparahydroxybenzoate) and 1% of sodium chloride as an ionic strength controlling agent. Poloxamer gel was prepared with three different buffer solutions (pH 1.2, 4.0 and 6.8) and the physicochemical properties, gelation temperature, gel strength and bioadhesive force, were determined. In the results, the effect of additives on the physicochemical properties was dependent on their bonding capacities including hydrogen bonding and cross-linking bonding. Because the hydrogen-bonding capacities of acetaminophen, ethanol and propylene glycol were smaller than that of poloxamer, the binding force of poloxamer gel became weak by their putting in between poloxamer gel. Therefore, the gelation temperature (15/15, $35.7^{\circ}C$ vs 37.0, 39.4 $38.2^{\circ}C$; 15/20, $29.2^{\circ}C$ vs 31.2, 32.0, $30.3^{\circ}C$) increased, and gel strength (15/15, 4.03 see vs 2.72, 2.08, 3.12sec; 15/20, 300g vs 50, 50, 200g) and bioadhesive force (15/15, $6.8{\times}10^2\;dyne/cm^2$ vs 3.2, 6.0, $6.0{\times}10^2\;dyne/cm^2$; 15/20, $97.3{\times}10^2\;dyne/cm^2$ vs 11.1, 89.5, $92.0{\times}10^2\;dyne/cm^2$) decreased. Furthermore, the binding force of poloxamer gel became strong due to the hydrogen-bonding capacities of glycerin and the cross-liking bonding of sodium salt. Then, the gelation temperature (15/15, 35.0, $32.1^{\circ}C$; 15/20, 26.0, $21.0^{\circ}C$) decreased, and gel strength (15/15, 6.51 see, 300g; 15/20, 500, 650g) and bioadhesive force (15/15, 7.2, $81.6{\times}10^2\;dyne/cm^2$; 15/20, 112.3, $309.2{\times}10^2\;dyne/cm^2$) increased. The effect of pH on the physicochemical properties of poloxamer gel was dependent on the ingredients with which the buffer solutions were prepared. Poloxamer gels prepared with pH 1.2 and 4.0 buffer solutions had the increasing gelation temperature (15/15, 37.5, $38.1^{\circ}C$; 15/20, 33.1, $34.0^{\circ}C$) and the decreasing gel strength (15/15, 2.98, 3.81sec; 15/20, 200, 200g) and bioadhesive force (15/15, $7.0{\times}10^2dyne/cm^2$; 15/20, $74.0{\sim}88.1{\times}10^2dyne/cm^2$) owing to HCl. Poloxamer gel prepared with pH 6.8 buffer solutions had the decreasing gelation temperature (15/15, $27.2^{\circ}C$; 15/20, $22.3^{\circ}C$) and the increasing gel strength (15/15, 400g; 15/20, 550g) and bioadhesive force (15/15, $207.0{\times}10^2dyne/cm^2$; 15/20, $215.0{\times}10^2dyne/cm^2$) due to the cross-linking bonding of $NaH_2PO_4\;and\;K_2HPO_4$.

• 한국세라믹학회지
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• 제32권9호
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• pp.995-1002
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• 1995

The alumina fiber was obtained by extruding the TEA complexed polymeric sol, synthesized by the alkoxide sol-gel method, through nozzle. The purpose of this study was to investigate the properties of fiber spun by TEA complexed sol. The analysis of sol indicated that TEA was bonded at alkoxide precursor and the optimum molar ratio for spinning was 0.5 mole of TEA, 3 mole of H2O. The cross section of the fiber from circular nozzle was not circular but oval, which indicated that the shape of nozzle did not affect the shape of fiber. The diameter of the fiber was about 100 ${\mu}{\textrm}{m}$ in the state of dried gel fiber, 60${\mu}{\textrm}{m}$ in calcined fiber, and the tensile strength of the fiber calcined at 90$0^{\circ}C$ was 2.1$\times$108 Pa.

• Journal of Industrial and Engineering Chemistry
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• 제67권
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• pp.326-332
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• 2018

In this study,the result shows that polyvinyl alcohol-sodium alginate (PVA-SA) gel bead crosslinked with sodium sulfate are better among the different methods by comparing the relative mechanical strength, mechanical strength swelling and expansion coefficient of beads in water. Subsequently, anammox biomass entrapment by PVA-SA gel was introduced into continuous stirred tank reactor (CSTR). After 24 operation days, the nitrogen removal efficiency achieved 60%, while the nitrogen loading rate (NLR) was $0.14kgN/m^3/d$ and the experiment data indicated that PVA-SA gel bead crosslinked with sodium sulfate can be used to initiate anammox process. Furthermore, it is an alternative for culturing anammox in a long-term operation.

• 한국식품조리과학회지
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• 제11권5호
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• pp.542-547
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• 1995

Pectinesterase was isolated from the culture medium of Aspergillus japonicus and partially purified by DEAE-Sephadex batchwise, Sephadex G-75 gel filtration and ion exchange chromatography. The purified enzyme solution was completely free from polygalacturonase which depolymerizes pectin molecule. The ability of the pectinesterase to demethylate high methoxyl pectin was investigated. On 20 minute of incubation methoxyl content of low methoxyl pectin decreased from 88％ to 6.93%. In general gel prepared with the pectin containing lower methoxyl content showed the lower value of percent sag, and showed the hieher Bel strength. Textural characteristics of pectin gel determined by Rheometer showed that as the methoxyl content was lowered, hardness and resilience of the gel were increased and cohesiveness was decreased. Apple juice containing HMP and organic acids can be converted into low methoxyl pectin apple jelly by the action of pectinesterase and addition of calcium ion. The strength of low methoxyl pectin apple jelly increased when it stored at room temperature.

• 한국식품조리과학회지
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• 제12권4호
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• pp.571-576
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• 1996

The moisture-dependent gelation characteristics of five different proteins are evaluated to understand the modification of gel strength when they are added in surimi gel. Compressive force and penetration force of protein gels gradually decreased with increase of moisture level, with showing markedly decrease at certain point of moisture level called critical moisture level. The critical moisture level for gelation of SPI-1, SPI-2, EW, WPC and LA were 79.4%, 81.6%, 91.4％, 87,8% and 84.7%, respectively. Beyond this critical level of water, protein gel matrix begins to lose its water binding and structural integrity. The mnisture that was not re tained by a protein was available to diluting the protein matrix and eventually weakened the overall gel strength. EW and MPI showed higher water retention than those of SPI, WPC and LA. The compressive force of SPI, WPC and LA-incorporated surimi gel at the varying moisture levels strongly correlated with the amount if water retained at corresponding moisture level within those protein (r=0.99).