• 한국축산식품학회지
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• 제33권1호
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• pp.58-66
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• 2013

In this study, the effect of packaging methods [aerobic packaging (AP), vacuum packaging (VP) and modified atmosphere packaging (MAP: 75% $N_2$, 25% $CO_2$)] on colour, lipid quality and microbial growth of beef patties enhanced with flaxseed flour was investigated during storage at $2{\pm}1^{\circ}C$ for 10 d. L and a values of beef patties packaged in MAP and VP were higher (p<0.05) than that of the samples packaged in AP. Packaging in MAP and VP retarded the lipid oxidation (TBA value) and inhibited the bacterial growth of beef patties enhanced with flaxseed flour. Furthermore, TBA values in beef patties were correlated with a values (r = -0.340; p<0.05). Packaging in MAP was more effective than packaging in VP for inhibiting microbial growth. The samples packaged in VP lost their shape due to the compression by external atmosphere. Packaging treatment had no significant effect on saturated fatty acid (SFA), monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid (PUFA) levels in beef patties. The a and b, TBA and MUFA values changed during storage time. TBA values for beef patties increased during storage time, but did not reach to the limit value (1 mg/kg) until the end of the storage time. The results suggest that the shelf life of beef patties enhanced with flaxseed flour can be extended by packaging in MAP.

• 한국미생물·생명공학회지
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• 제49권3호
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• pp.320-328
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• 2021

High GABA-enriched yeast extract, for various nutritionally and pharmaceutically important functional foods, was prepared using a novel isolate of Debaryomyces hansenii JBCC541. Under optimized conditions, GABA conversion rates are significantly enhanced up to 7.55 g/l by D. hansenii JBCC541, increasing their synthesis yield 40 times. The total amino acid content of the prepared yeast extract was 10733.86 mg/l (257.36 mg/g), consisting of alanine, lysine, glutamine, leucine, and valine as the primary amino acids. The GABA content was significantly enhanced up to 6790 mg/l (162.80 mg/g) in the presence of glutamic acid, with approximately 10-fold higher GABA production. Flavor amino acids were also highly enhanced, indicating that the prepared yeast extract might be useful for preparing various functional and sensuous foods. Our results were promising as a GABA-enriched yeast extract preparation tool ensuring a suitable food material level with the potential for functionally enhanced food industrial applications.

• 한국표면공학회지
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• 제52권5호
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• pp.275-281
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• 2019

Anodization is widely used to enhance the properties of aluminum, such as hardness, electric resistance, abrasion resistance, corrosion resistance etc. But these properties can be enhanced with additional process. According to the partial crystallization of oxide layer with post heat treatment, enhanced hardness can be expected with partial crystallization. In this study, post heat treatments were applied to the anodized aluminum alloys of Al6061 to achieve the partial crystallization, and crystallizations were evaluated with the reduced breakdown voltages. Interestingly, remarkable enhanced hardness (21~29%), abrasion resistance (26~62%), and reduced breakdown voltage (24~44%) were observed for the sulfuric acid anodized samples when we annealed the anodized samples with 1hour post heat treatment at $360^{\circ}C$. For the Al5052 alloys, a lot of cracks were observed when we applied the post heat treatment.

• 대한의생명과학회지
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• 제10권2호
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• pp.115-120
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• 2004

To investigate the correlation between the magnetic resonance imaging (MRI) of cerebral fat embolism that is induced by injecting oleic acid into 10 cats, and a pathologic diagnosis. Using a microcatheter, 30 ${mu}ell$ of oleic acid was injected into the internal carotid artery of 10 cats. MR T2-weighted image (T2WI), diffusion-weighted image (DWI) and Gadolinium-enhanced T1-weighted image (Gd-enhanced T1WI) were obtained after 30 minutes and 2 hours of embolization. After 30 minutes of the embolization, lesions of very high signal intensity were detected by T2WI in 6 cats, and of slightly high signal intensity in 2 cats; in the remaining 2 cats, signal intensity was normal. DWI showed lesions of very high intensity in 9 cats and of slightly high intensity in one cat. According to the findings of light microscopic examination, infarcted lesions mainly involved the gray matter, but also some white matter. A magnetic resonance imaging diagnosis for cerebral fat embolism that was induced by oleic acid through the internal carotid artery in cats showed high signal intensity on the T2WI and the DWI within an initial 2 hours, and with a well enhancement on the Gd-enhanced T1WI. Considering cellular edema, cerebrovascular injury and extracellular space widening, we assumed pathologically that cytotoxic and vasogenic edema exists at the same time.

• The Korean Journal of Ecology
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• 제19권5호
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• pp.385-392
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• 1996

Changes in polyamine titers and enzyme activities during radicle growth of Glycine max were studied in order to investigate the effect of ferulic acid in regulation of polyamine biosynthesis. Among eight compounds used, gallic acid stimulated the radicle growth and ferulic acid inhibited it significantly. During the radicle growth of Glycine max, the content of putrescine was shown the highest level at the second day, while at the fourth day spermidine was the highest and spermine followed. Ornithine decarboxylass (ODC, EC 4.1.1.17) seems to be responsible for biosynthesis of putrescine. As the concentration of ferulic acid (0.001, 0.01, 0.1 mM) treated increased, the content of spermine was gradually enhanced and putrescine was increased at 0.001~0.01 mM, decreased after 0.1 mM concentration but spermidine was not affected. Ferulic acid elevated ODC and S-adenosylmethionine decarboxylass (SAMDC, EC 4.1.1.50) activity. ODC activity was increased more than 120% and SAMDC activity was increased about 50% more than that of the control. Diamine oxidase (DAO EC, 1.4.3.6) activity was enhanced about 20% at low concentration, decreased after then.

• KSBB Journal
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• 제17권1호
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• pp.49-53
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• 2002

GABA가 고함유된 발아현미를 생산할 수 있는 전략을 마련하고자 현미발아시 통상적인 물발아구 외에 젖산발아구, glutamic acid발아구로 나누어 발아 이전의 현미와 GABA 및 일부 유리아미노산 함량을 비교분석하였다. 5 mM glutamic acid 용액을 발아에 사용한 경우 가장 높은 GABA 함량 증진을 보여 시료 g당 및 시료 추출물 중의 단백질 mg당 증가정도가 발아하지 않은 현미에 비해 각각 8배와 12배로 나타났다. 또한 glutamic acid 발아구는 물발아나 젖산발아시 현저히 감소되던 serine의 함량을 오히려 증진시켰다. 모든 발아구에서 GABA 및 alanine 함량이 증진된 것과 는 반대로 glutamic acid와 aspartic acid 함량은 현저히 감소 하였다. 이는 발아 과정에 의해 glutamic acid는 GABA로 aspartic acid는 alanine으로 전환된 것에 기인된 것이라 여겨진다. 이상의 결과를 종합하면 현미발아시 glutamic acid액을 사용하면 기능성 물질인 GABA 함량을 현저히 증진시키며, serine의 감소를 막을 수 있어 기능성이 보강된 발아현미를 얻을 수 있을 것으로 기대된다.

• 한국수산과학회지
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• 제51권6호
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• pp.613-622
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• 2018

This study investigated changes in the quality and antioxidant activity of soy sauce with added Saccharina japonica powder (FSP). Soy sauce was prepared with acid-hydrolyzed soy sauce, brewed soy sauce, honey, ginger, garlic, dried red pepper, ${\gamma}$-aminobutyric acid (GABA)-enriched sea tangle fermented in lactic acid, and 1% or 3% S. japonica powder by soy sauce volume. The color, pH, microbiology, amino nitrogen, free amino acids, antioxidant activity, and sensory qualities of the soy sauce were evaluated. There were no significant differences in the general characteristics or antioxidant activity. However, the addition of FSP to the soy sauce enhanced the delicate flavor. Furthermore, soy sauce containing FSP had higher levels of GABA (50 mg/100 mL), a biofunctional ingredient. Therefore, the development of seasoning soy sauce with enhanced functionality seems possible.

• 한국미생물·생명공학회지
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• 제44권4호
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• pp.488-492
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• 2016

S. fibuligera 균주는 생전분을 분해하는 활성이 있는 효모 균주이다. 본 연구에서는 첨가되는 젖산의 농도가 점차 증가하는 장기간 반복 회분식 배양 방법을 사용하는 적응진화를 통하여 S. fibuligera 균주의 젖산에 대한 내성을 증진시키고자 하였다. 진화된 균주인 S. fibuligera MBY1940 균주는 비성장속도 측정과 평판배지를 사용하는 성장분석을 통하여 모균주가 성장할 수 없는 젖산 농도 2.5%에 대해서도 내성을 나타내는 것을 확인하였다. 전자현미경 관찰을 통하여 젖산이 첨가된 스트레스 조건에서 모균주는 신장된 세포 형태와 세포막에 손상을 입은 것으로 보아 진화된 균주에 비해 젖산에 대하여 상대적으로 취약한 것으로 판단되었다.

• Korea-Australia Rheology Journal
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• 제17권2호
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• pp.79-85
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• 2005

Aqueous mixtures of hyaluronic acid and poly(vinyl alcohol) system and hydrogels thereof were introduced to obtain new bioartificial materials that have excellent mechanical properties, biocompatibility and enhanced rheological properties. The interactions between hyaluronic acid and poly(vinyl alcohol) and/or borax were investigated by rheological measurements. Preparation parameters of the aqueous mixtures were mixture composition, the degree of hydrolysis of poly(vinyl alcohol) and borax concentration. From the rheological behavior, it could be deduced that the key factor of the interaction between hyaluronic acid and poly(vinyl alcohol) was the hydrogen bonding between them and the effect was pronounced with borax. Enhanced viscosity was observed at the composition of $20wt\%$ of hyaluronic acid solution and $80wt\%$ of poly(vinyl alcohol) and borax solution. Rheological properties were influenced by the degree of hydrolysis of poly(vinyl alcohol) and borax concentration. As the degree of hydrolysis and borax concentration increased, rheological properties increased due to the increased hydrogen bonding and networking of hyaluronate aggregates. Physical hydrogels from hyaluronic acid and poly(vinyl alcohol) were prepared and the composition dependence of the gels was rheologically investigated as well.

• 응용화학
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• 제15권1호
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• pp.29-32
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• 2011

Surfactant enhanced fluorescence (FL) of europium-salicylic acid (SA) complex has been studied. It was observed that weak FL of Eu(III) at the wavelength of 589 nm and 612 nm was found to be enhanced after addition of salicylic acid and cetyltrimethylammonium bromide (CTAB) surfactant upon excitation at 395 nm. Under optimized condition, FL intensity of Eu(III) at 612 nm responded linearly with the concentration of SA in the range of 5.5×10^-9 to 1.5×10^-6 M of SA. The detection limit was calculated from the calibration curve(3Sb/m) as 9.27×10^-9 M.