• Journal of Life Science
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• v.14 no.2
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• pp.291-295
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• 2004

Rooibos (Aspalathus linearis) (RB) is a leguminous shrub native to the mountainous areas of the northwestern Cape Province in South Africa. RB tea infusions are the fermentation products of its leaves and fine sterns, and known to have a high antioxidative activity due to the presence of flavonoids and phenolic acids. We investigated the effects of RB tea on the alleviation of oxidative stress on cultured rat cortical neurons in a hypoxic model. Measurement of lactate dehydrogenase (LDH) released into culture media revealed that RB increased cell viabilities in both normoxia (6-18%) and hypoxia (2-24%) dose-dependently (10-100 $\mu\textrm{g}$/ml) on 16 days in vitro (3 days after treatment). Visualization of cell morphology by expression of GFP-Hsc70 fusion protein showed that RB (50 $\mu\textrm{g}$/ml) reduced the average vacuolated soma from 55.4$\pm$4.59% (no RB addition) to 40.9$\pm$6.3% (RB addition) on 5 days after hypoxia. Our results proves efficacy of RB in the neuroprotection of hypoxic neurons and extend application for RB into the prevention and/or treatment of neuronal damages.

• Korean Journal of Food Science and Technology
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• v.30 no.1
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• pp.62-68
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• 1998

To develop methods to produce low salt fermented squid with rich flavor and acceptable shelf life, the optimum processing conditions such as water activity of raw material, amounts of NaCl, papain and gucose were investigated. Water activity of squid meat was adjusted to 0.94 (raw meat), 0.90 and 0.88 by cold air blast and each was salted with 3, 5, or 7% NaCl followed by fermenting at $10^{\circ}C$ for 6 weeks. Amino nitrogen was increased rapidly with high water activity and low NaCl concentration. As a result of organoleptic evaluation it was concluded that optimum conditions were to adjust water activity of raw material to 0.90 and to salt with 5% NaCl. When squid meat adjusting water activity to 0.90 was treated with 0.05, 0.1 and 0.5% papain and fermented at $10^{\circ}C$ for 6 weeks, SDS-PAGE pattern showed rapid breakdown of myofibrilar protein with increasing amounts of papain but the treatment with 0.1% enzyme was best organoleptically. pH values of squid meat added with 1 and 2% glucose were maintained lower than control (glucose 0%) but there were no significant differences between the two glucose treatments. Therefore, it was thought that adding of glucose might be extended shelf life of fermented squid with low salt concentration.

• Korean Journal of Food Science and Technology
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• v.14 no.1
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• pp.36-42
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• 1982

An investigation on optimum processing conditions for meaty textured fish protein concentrate (MT-FPC) was carried out with the fish meat of filefish, Navodon modestus, and sandfish. Arctoscopus japonicus. The processing conditions were determined by the lipid content and the rehydration capacity of MT-FPC. The optimum pH and sodium chloride content of fish meat were 8.0 and 1.0%, respectively. The most effective soaking conditions were: soaking time in chilled ethanol was 15 min for both filefish and sandfish; amount of chilled ethanol, 3 volumes and 4 volumes for filefish and sandfish, respectively; temperature of chilled ethanol, $25 ^{\circ}C$ for both filefish and sandfish; soaking time in boiling ethanol, 15 and 25 min for filefish and sandfish, respectively; amount of boiling ethanol, 2 and 4 volumes for filefish and sandfish, respectively; and number of snaking in boiling ethanol, 2 and 4 times for filefish and sandfish, respectively. Yields of the product to the minced meat weight, the contents of protein and lipid in MT-FPC prepared from filefish were 13.7%, 84.5% and 0.2%, and those from sandfish were 12.5%, 84.2% and 1.1%, respectively.

• Korean Journal of Food Science and Technology
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• v.15 no.3
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• pp.252-261
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• 1983

Isopropyl alcohol extracted filefish protein concentrate (FPC) and NaOH hydrolyzed filefish protein isolate (FPI) were used for the investigation on the effect of processing conditions on the molecular distribution and functional properties. The molecular distribution of FPC on polyacrylamide gel showed a resemblance to that of fish muscle, but that of alkaline hydrolyzed FPI showed the severe degradation of protein. The content of several amino acids in FPI were lower than those of FPC. The pepsin digestibility of the FPC dried at high temperature was relatively high. FPC didn't exhibit a significant difference in nitrogen solubility at the pH range of 3.0-9.0, while FPI showed a wide difference with the pH change. FPI was more suspensible and rehydrated in water than FPC. Although the aeration capacity of FPI was very low, foam viscosity was higher than that of FPC. In contrast with aeration capacity, FPI presented higher emulsion capacity and lower emulsion viscosity than FPC. The size of fat globule in the emulsion of FPC was larger than that of FPI. In general, most functional properties decreased with the increment in drying temperature, except water holding capacity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.7
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• pp.857-867
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• 2017

This study was performed to encapsulate low molecular weight marine collagen and ${\gamma}$-aminobutyric acid (GABA)-producing lactic acid bacteria to inhibit degradation and improve survival rate during exposure to adverse conditions of the gastro-intestinal tract. Calcium-alginate method was used for the manufacture of a double-layered coated capsule. The inner core material was composed of collagen and lactic acid bacteria, and the coating materials were alginate and chitosan. The sizes and shapes of the double-coated capsule were affected mainly by centrifuge speed and pH. Manufactured capsules were observed with a scanning electron microscope and by confocal laser scanning microscopy to confirm the micromorphological changes of capsules and bacterial cells. As a result, double-layered coated capsules were not degraded at pH 1.2, whereas degradation occurred at pH 7.4. In addition, GABA and collagen were maintained in stable state at pH 1.2. Therefore, double-layered coated capsules developed in this study would not be degraded in the stomach and could be stably delivered to the small intestine to benefit intestinal and dermatic health.

• Journal of the Korean Geosynthetics Society
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• v.19 no.2
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• pp.23-33
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• 2020

This study determines the basic properties and acid rock drainage generation capacity of Pohang tertiary mudstone through laboratory experiments. According to X-ray fluorescence (XRF) analysis results, the mudstone of this area mostly comprised of SiO₂ with a proportion of approximately 60%, followed in order by Al₂O₃ and Fe₂O₃. As such, it is clear that there is an abundance of aluminosilicates with a high probability of generating acid rock drainage. The XRD analysis showed that the mudstone contains pyrite (FeS₂), it is highly likely to generate acid rock drainage, and inductively coupled plasma atomic emission spectroscopy (ICP-AES) analysis results showed that the mudstone samples contained a high amount of Fe²⁺ ions. As a result of anion analysis measured by ion chromatography (IC), all mudstone samples were measured to have high SO^2-₄ concentrations. According to elemental analysis, the total sulfur (S) content was high, which in turn indicates a high risk of acid rock drainage generation reflected by a maximum potential acidity (MPA) higher than 1%. All in all, although there were slight deviations between the tertiary mudstone samples, overall, the samples exhibited high acid rock drainage generation capacities.

• Korean Chemical Engineering Research
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• v.48 no.6
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• pp.741-746
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• 2010

Phospholipids were recovered from squid viscera residues by ethanol extraction after supercritical carbon dioxide($SCO_2$) extraction and from squid viscera was not processed $SCO_2$ by various organic solvent extraction. $SCO_2$ extraction were performed at $45^{\circ}C$ and 20 MPa for removal of non polar lipid molecules from freeze dried squid viscera sample. Phospholipids were extracted from freeze dried squid viscera sample by chloroform, hexane, methanol, and ethanol and from $SCO_2$extracted squid viscera sample by ethanol. The pH was fixed at 5.7 for all phospholipids extraction conditions. Phospholipid classes were analyzed by HPLC equipped with evaporative light scattering detector (ELSD). Phosphatidyl choline(PC) extracted by ethanol from $SCO_2$ extracted residues was higher than that of extracted by ethanol from squid viscera. But phosphatidyl ethanolamine(PE) and phosphatidic acid(PA) were extracted higher percentage in raw squid viscera. The fatty acid compositions in phospholipids extract by ethanol extract from $SCO_2$ extracted residues were analyzed by gas chromatography(GC). Docosahexanoic acid(DHA) was found in highest percentage in phospholipid extract.

• The Korean Journal of Food And Nutrition
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• v.17 no.1
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• pp.80-85
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• 2004

This study was performed to provide basic quality characteristics data of Kimchi by storage containers that will be applied for Kimchi storage container development of new material. In all storage containers, pH was decreased with increased storage days, while acidity was increased with increased storage days, The changes of pH and acidity by storage containers were alumina < stainless < bio < plastic. Salt content was same to all containers. In all storage containers, reducing sugars of Kimchi at first were 22.65${\pm}$0.04$\^$a/ mg/mL. But as these of alumina, stainless, bio and plastic at storage after 31 days were 11.18${\pm}$0.15$\^$a/ mg/mL, 5.39${\pm}$0.02$\^$b/, 3.74${\pm}$0.10$\^$c/, and 3.14${\pm}$0.02$\^$d/ mg/mL, respectively. The hardness, cohesiveness and gumminess of Kimchi by storage containers decreased with increased storage days. And the changes ratio of these were alumina < stainless < bio < plastic. The desirable organoleptic characteristic such as sourness, fresh cabbage taste and firmness were long time maintained at alumina container A significant evidence was detected that the alumina container showed less quality change than that of bio, stainless and plastic containers as storage days increased.

• The Korean Journal of Mycology
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• v.44 no.4
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• pp.300-306
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• 2016

Recently, the incidence of oak wilt disease has been increasing in Korea, resulting in an increasing number of dead trees. In this study, we performed sawdust bag cultivation of shiitake (Lentinula edodes) using oak wilt-diseased logs and measured the antioxidant activities of the resulting mushrooms. For sawdust media, 4 types of logs (healthy, infected, dead, and fumigated ones) were used. As inocula, three strains of L. edodes (NIFoS 764, Sanjo 701ho, and Sanmaru 2ho) were used. The productivity of L. edodes from dead logs was similar to that from healthy logs. Except for the Sanmaru 2ho strain, fumigated logs and infected logs yielded a lower productivity of L. edodes compared to healthy logs. In terms of antioxidant activity, L. edodes grown on sawdust from fumigated logs showed higher values than those from other logs.

• Polymer(Korea)
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• v.37 no.2
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• pp.127-134
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• 2013

The vascular endothelial cells are the inner layers of blood vessels. It regulates the function of blood vessels and proliferation of vascular smooth muscle cells. Poly(lactide-co-glycolic acid) (PLGA) is a biodegradable synthetic polymer with a well-controlled degradation rate and an acceptable mechanical strength. It can be easily fabricated into many shapes. Silk consists of 18 amino acids. It found important for attaching cells cultured in vitro, and maintaining cell functions. In this study, we fabricated silk/PLGA biomaterial hybrid films of 0, 10, 20, 40 and 80 wt% silk. We performed MTT, SEM, ELISA, and immunocytochemistry analyses. We confirmed the adhesion and the proliferation of HAECs on silk/PLGA according to the content of silk, and 40 wt% silk/PLGA hybrid films have superior adhesion and proliferation properties. These results demonstrate that silk/PLGA hybrid films provide suitable surfaces for HAECs, and there is the effect of silk on cell growth and proliferation.