• Korean Journal of Food Science and Technology
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• v.43 no.6
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• pp.742-746
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• 2011

To increase the quality of Korean traditional yakju, we prepared seed cultures by fermentation at $20^{\circ}C$ for 2 days after addition of 140% water, 3% nuruk and 1.5% yeast into cooked rice. After the 200% cooked rice, 120% water and 0.08% commercial saccharifying enzyme were added to seed cultures and fermented for 2 days at $20^{\circ}C$, wild ginseng was added and then further fermented for 5 days. Physicochemical properties of traditional yakju were investigated. Ethanol was produced (18.5%) by the addition of 1.2% wild ginseng. However, ethanol content was not increased by addition of microwave treated-wild ginseng and rice (either cooked rice or raw). The traditional yakju obtained by fermentation at $20^{\circ}C$ for 5 days, after 90 sec of microwave treated-wild ginseng was added into main fermentation broth, showed good total acceptability and also contained 791 ppm saponin.

• KSBB Journal
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• v.11 no.6
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• pp.718-725
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• 1996

Old newsprint was deinked with endoglucanase, exoglucanase and their various compositions from Trichoderma viride. The yield decreased with an increase in enzyme concentration. Especially, it was the lowest in the treatment of endo-exo mixture(1:1). It may be regarded as a synergistic actions of the cellulase components. The brightness was the highest in pulp deinked with endo-exo mixture(1:1). Maximum brightness was observed when 0.5mg/mL of the endo-exo mixture was used. The physical strength increased with increasing concentration in exoglucanase. But, it decrease with increasing concentration in endoglucanse and endo-exo mixture(1:1). Also, we investigated the yield, brightness and physical strength of endoglucanase in combination with exoclucanase(12:1, 8:1, 4:l, 1:1, 1:4, 1:8, 1:12). Maximal deinking conditions, obtained at a specific optimal ratio of endoglucanase to exoglucanse are as follow ; 12:1 for yield, 12:1 for brightness, 4:1 for tensile strength, 12:1 for bursting strength, and 8:1 for tearing strength. These results indicated that the deinking depended largely upon the action of endoglucanase. Exoglucanase was occupying more than 60% of the total crude cellulase contents. Therefore, the most effective deinking must repress the action of exoglucanase.

• Korean Journal of Microbiology
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• v.51 no.4
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• pp.364-373
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• 2015

As an effort to utilize alginate, 103 bacterial isolates that were positive for the alginate lyase activity were isolated from various clams and seawater samples collected in Incheon coastal area. Among them, 3 strains (M1-2-1, M6-1, and C8-15) were finally selected for further analysis based on their activities at higher levels than others. These isolates were all Gram-negative and rod shaped halophilic bacteria with motility. According to their physiological and biochemical properties as well as DNA sequence of their 16S rRNA genes, M1-2-1 and M6-1 were identified as a member of genus Pseudoalteromonas and C8-15 belonged to genus Vibrio. They exhibited the alginate degrading activity at the maximal level when they were cultured in APY broth for 6-8 h at $25^{\circ}C$. Both their growth and the enzyme activity were greatly enhanced when NaCl was added to the growth medium. The crude alginate lyases from the supernatants of the bacterial cultures showed the highest activity at $45^{\circ}C$ and pH 7.0-8.0. M1-2-1 and M6-1 produced 2.723 and 1.976 g/L of reducing sugar from alginate, respectively, suggesting that they have potential for commercial application.

• Korean Journal of Food Science and Technology
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• v.35 no.5
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• pp.943-950
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• 2003

To identify the functional properties of Hongkuk ju and to improve its brewing process, Hongkuk ju was brewed using different hongkuks (Monascus red koji) made by Monascus purpureus, Monascus anka, Monascus aruneosus, and nuruk. Hongkuk using M. purpureus showed the highest enzyme activity. Hongkuk ju prepared with the M. purpureus hongkuk was fermented most efficiently, and showed the highest Hunter value. Hongkuk ju showed significant levels of phenolic compounds, electron donating ability, nitrate-scavenging activity, and ACE inhibition activity. In particular, Hongkuk ju made with M. purpureus showed the highest value among the wines of this study.

• Food Science and Preservation
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• v.19 no.5
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• pp.757-766
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• 2012

The SSH100-10 bacterial strain, which exhibits strong antifungal (anti-mold and anti-yeast) activity, was isolated from traditional korean soysauce aged 100 years. The strain was identified as Bacillus velezensis based on Gram-staining, the biochemical properties and 16S rRNA gene sequence determination. B. velezensis SSH100-10 showed strong proteinase activity and NaCl tolerance, but did not produce enterotoxin. Two-antifungal compounds from B. velezensis SSH100-10 were purified using SPE, preparative HPLC, and reverse phase-HPLC. The purified antifungal compounds were identified as $C_{14}$ and $C_{15}$ iturin through MALDI-TOF-MS and amino acid composition analysis. The stability characteristics of the antifungal compounds after temperature, pH, and enzyme treatments suggested that B. velezensis SSH100-10 produced more than two antifungal compounds; pH-stable $C_{14}$ iturin A and $C_{15}$ iturin A, and unidentified pH-unstable compounds. The results suggested that B. velezensis SSH100-10 can be used in soybean fermentation as a starter. Moreover it has potential as a biopreservative in the food and feed industry and as a biocontrol agent in the field of agriculture.

• Applied Chemistry for Engineering
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• v.35 no.2
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• pp.67-78
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• 2024

Light absorption has potential as a signal in biochemical analyses due to its simplicity in measurement and interpretational clarity. Among substances that generate absorption signals, gold nanoparticles possess advantages such as chemical stability, biological compatibility, and unique optical properties from the localized surface plasmon resonance (LSPR) in the visible light range. They also exhibit versatility compared to other colorimetric substances effective only for specific target molecules, as they easily conjugate with various detection active substances like antibodies and aptamers. Particularly due to advantages such as low cost, ease of particle synthesis, and high environmental stability compared to enzyme-based colorimetric methods, gold nanoparticles are extensively researched as signal substances in colorimetric assays. This review summarizes various strategies utilizing gold nanoparticles as absorption signal substances, focusing on recent research. Based on the characteristics of gold nanoparticles, where the optical property is influenced by particle morphology, literature is classified and reviewed based on strategies controlling the shape of gold nanoparticles during signal generation. Through this, it is observed that gold nanoparticles, which have been used as absorption signal substances, continue to be actively researched, affirming their potential for broad and continuous improvement in the future.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.4
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• pp.876-881
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• 1999

Fresh onions were extracted by two methods of conventional extraction(CE) and microwave assisted extraction(MAE) under different extraction conditions. Onion extracts obtained by CE and MAE were examined in oleoresin yield and physiological activities. The optimal extraction time of MAE was about 5 minutes, whereas that of CE was 2 hours. Therefore extraction time was shortened drastically by MAE but there was no significance in oleolesin yield. The electron donating abilities also showed negligible difference between two extracts obtained by CE and MAE, and 45% level in CE and 50% level in MAE. The nitrite scavenging effect was diminished while pH was increasing, and showed a high elimination effect over 85% at pH 1.2. The tyrosinase inhibitory effect was 20% level in both CE and MAE when water was used and 40% level when ethyl alcohol was used. The angiotensin I converting enzyme inhibitory effect showed higher activity with 70% level in MAE than 60% level in CE. The pyruvic acid content was 6.8 and 6.4 moles per 1g of fresh onion by CE and MAE when water was used, and was 4.3 and 5.6 moles by CE and MAE when ethyl alcohol was used.

• Journal of Animal Science and Technology
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• v.51 no.2
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• pp.171-176
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• 2009

A bacterial strain producing intracellular phytase was isolated from cultivable soil near cowsheds and identified as a fluorescent Pseudomonas sp. BUN1. The BUN1 phytase, partially purified by cation and anion exchange chromatography, exhibited its optimal activity at $40^{\circ}C$ and pH 5.5. As for substrate specificity, it was very specific for phytate and showed little activity on other phosphorylated conjugates. Its activity was greatly inhibited by metal ions such as $Cu^{2+}$, $Cd^{2+}$, and $Zn^{2+}$. Addition of corn starch to PSM (phytasesynthetic medium) [0.5% sodium phytate, 0.5% $(NH_4)_2SO_4$, 0.5% KCl, 0.01% $MgSO_4\cdot7H_2O$, 0.01% $CaCl_2\cdot2H_2O$, 0.01% NaCl, 0.001% $FeSO_4\cdot7H_2O$, 0.001% $MnSO_4\cdot4H_2O$; pH 6.5] for the phytase production significantly induced its enzyme activity in comparison with other carbon sources tested.

• Korean Chemical Engineering Research
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• v.60 no.1
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• pp.1-6
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• 2022

As the demand for wearable devices increases, many studies have been studied on the development of flexible electrode materials recently. In particular, the development of high-performance flexible electrode materials is very important for wearable sensors for healthcare because it is necessary to continuously monitor and accurately detect body information such as body temperature, heart rate, blood glucose, and oxygen concentration in real time. In this study, we fabricated the nonenzymatic glucose sensor based on polyaniline/carbon nanotube fiber (PANI/CNT fiber) electrode. PANI layer was synthesized on the flexible CNT fiber electrode through electrochemical polymerization process in order to improve the performance of a flexible CNT fiber based electrode material. Surface morphology of the PANI/CNT fiber electrode was observed by scanning electron microscopy. And its electrochemical characteristics were investigated by chronoamperometry, cyclic voltammetry, electrochemical impedance spectroscopy. Compared to bare CNT fiber electrode, this PANI/CNT fiber electrode exhibited small electron transfer resistance, low peak separation potential and large surface area, resulting in enhanced sensing properties for glucose such as wide linear range (0.024~0.39 and 1.56~50 mM), high sensitivity (52.91 and 2.24 ㎂/mM·cm²), low detection limit (2 μM) and good selectivity. Therefore, it is expected that it will be possible to develop high performance CNT fiber based flexible electrode materials using various nanomaterials.

• Microbiology and Biotechnology Letters
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• v.36 no.4
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• pp.276-284
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• 2008

A lactic acid bacterium having antifungal activity was isolated from kimchi. It was identified as Lactobacillus plantarum based on its morphological and biochemical properties, and 16S rRNA sequence, and designated as Lb. plantarum AF1. This isolate inhibited the growth of Aspergillus flavus ATCC 22546, A. fumigatus ATCC 96918, A. petrakii PF-1, A. ochraceus PF-2, A. nidulans PF-3, Epicoccum nigrum KF-1, and Cladosporium gossypiicola KF-2 under a dual culture overlay assay. Also, the antimicrobial activity was found to be active against various species of Gram-positive and Gram-negative bacteria. The antifungal activity was found to be stable after heat ($121^{\circ}C$, 15 min) and proteolytic enzyme treatment, but it was unstable over pH 5.0. The antifungal compound(s) was estimated to have a low molecular mass (below 3,000 Da).