• Korean Journal of Food Science and Technology
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• v.27 no.2
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• pp.216-220
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• 1995

In order to investigate the possible use of vegetable kimchi stuff as natural preservatives for kimchi, the methanol extracts of 15 kinds of vegetable kimchi stuff were solvent-fractionated and fractions were tested for antimicrobial activities against Leuconostoc mesenteroids, Pediococcus cerevisiae, Lactobacillus plantarum and Saccharomyces cerevisiae. The neutral fractions of the extracts of garlic and leek showed strong antimicrobial activities. The extract of leek showed particularly strong antimicrobial activities against Ped. cerevisiae and L. plantarum that were known to be main microorganism of fermentation and acidification of kimchi. The results suggest the possible use of the leek extract as natural preservatives for kimchi.

• Korean Journal of Plant Resources
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• v.24 no.1
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• pp.10-16
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• 2011

We investigated the antimicrobial activity of ether and ethylacetate fractions from Artemisia capillaris and Artemisia iwayomogi used as Injin. The antimicrobial activity of the ethylacetate fractions from Artemisia capillaris and Artemisia iwayomogi for tested microbes were stronger than those of ether fractions of the two Artemisia plants. The antimicrobial activity of fractions of Artemisia iwayomogi was higher than that of fractions of Artemisia capillaris for the tested microbes. The extracts of young shoots and leaves showed stronger antimicrobial activity than those of young leaves. The range of minimum inhibitory concentrations(MICs) of ethylacetate fractions from the part of Artemisia capillaris and Artemisia iwayomogi were 0.25~2.0 mg/ml. The MICs of ether fractions were showed higher concentration than those of ethylacetate fractions. The fractions of Artemisia iwayomogi showed lower MICs than fractions of Artemisia capillaris. The highest total polyphenol content was found in young shoots and leaves of A. capillaris. The young shoots and leaves of the two kinds of Artemisia plants showed higher content of total polyphenol.

• Journal of the Korean Society of Food Culture
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• v.20 no.5
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• pp.603-607
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• 2005

Fourteen phenolic compounds(benzoic acid, p-hydroxybenzoic acid, protocatechuic acid, vanillic acid, syringic acid, gallic acid, caffeic acid, ferulic acid, (+)-catechin, quercetin, rutin, catechol, chlorogenic acid and L-ascorbic acid) were examined for their effects on the anticarigenic activity. Among tested samples, catechol was significantly inhibited the S. mutans, exhibiting an clear zone 18.5-19.5mm by 10 mg/disc level. The minimal inhibition concentration(MIC) of the phenolic compounds for Streptococcus mutans, M1 and M2 strain were determined as 2,000 ppm, whereas catechol was 1,000 ppm. The activity of glucosyltransferase(GTase) was significantly inhibited by catechol, at 10 ppm(58.7%), 50 ppm(60.7%) and 100 ppm(88.4%) and 500 ppm(89.6%), respectively. Among them, catechol showed most significant anticariogenic activity as well as inhibition of GTase activity.

• Microbiology and Biotechnology Letters
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• v.42 no.2
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• pp.207-210
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• 2014

Viral infections are capable of inducing reactive oxygen species (ROS) production in the infected cells and antioxidants have been reported to have antiviral activities against many viruses. In this study, an antiviral assay using the cytopathic effect (CPE) reduction method revealed that gallic acid possesses good anti-coxsackievirus B3 (CB3) and coxsackievirus B4 (CB4) activities, reducing the formation of visible CPE. However, ribavirin did exhibit weak anti-CB3 and CB4 activities and was unable to prevent CPE. Therefore, we conclude that the inhibition of CB3 or CB4 production by gallic acid may be due to its general action as an antioxidant.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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• pp.10-10
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• 2018

미생물 및 식물 등이 가지고 있는 많은 천연물질은 항균, 항암, 강장작용 등 다양한 생리활성 기능이 있다고 알려져 있으며, 의약품의 원료로도 많이 이용되고 있다. 또한, 미생물을 통한 발효는 거대분자를 낮은 분자량의 물질로 분해하여 인체의 흡수를 용이하게 할 수 있을 뿐만 아니라 미생물이 자체적으로 합성하는 다양한 대사산물과 발효과정에서 기존 물질에 다양한 잔기를 가감함으로서 새로운 물질이 만들어질 수 있는 장점이 있다. 본 연구에서는 구절초의 추출물을 바탕으로 발효를 진행하여 항산화 활성 및 항비만 활성 등을 발효 전 후로 비교하여 분석하고 이를 통하여 구절초 추출물을 활용한 발효제품 개발을 추진하였다. 구절초 잎과 전초의 항산화활성 측정 결과 전반적으로 구절초 전초보다는 잎 추출물에서 항산화 활성이 높게 나타났으며 구절초 잎을 70% 에탄올로 추출한 추출물에서는 비타민C보다 3.93% 항산화 활성이 높게 나타났다. 구절초 발효액의 항산화 활성 측정 결과 발효하지 않은 시료보다 발효한 시료에서 항산화 활성이 더 높게 나타났다. 더욱이, 항비만 활성과 추출물의 혈중콜레스테롤 저감 활성도 발효추출물에서 유의하게 증가하였다. 이러한 결과는 구절초 발효 추출물이 구절초 추출물에 비하여 기능성 활성이 향상되었음을 나타내고 있으며, 이러한 결과를 바탕으로 건강기능성음료 등 다양한 제품으로의 응용이 가능할 수 있음을 시사한다.

• Microbiology and Biotechnology Letters
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• v.37 no.4
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• pp.340-349
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• 2009

A CJ9 bacterial strain, which showed antifungal and antibacterial activities, was isolated from meju and identified as Bacillus polyfermenticus based on Gram staining, biochemical properties, as well as its 16S rRNA sequence. B. polyfermenticus CJ9 showed the antimicrobial activity against the various pathogenic molds, yeasts, and bacteria. The antibacterial activity was stable in the pH 5.0~9.0, but the activity was lost at $37^{\circ}C$ for 24 hr. The antifungal activity was stable in the pH range of 3.0~9.0 and reduced at $121^{\circ}C$ for 15 min, but antifungal activity was not completely destroyed. The antibacterial activity was completely inactivated by proteinase K, protease, trypsin, and $\alpha$-chymotrypsin. The antifungal activity was also completely inactivated by protease and $\alpha$-chymotrypsin, and reduced its activity by proteinase which indicated that the antifungal and antibacterial compounds have proteineous nature. The apparent molecular mass of the partially purified antifungal compound, as indicated by using the direct detection method in Tricine-SDS-PAGE, was approximately 1.4 kDa. The molecular mass of the antibacterial compound could not be determined because of its heat-liable characteristic.

• Journal of Life Science
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• v.32 no.1
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• pp.1-10
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• 2022

Natural products have gained increasing attention due to their advantage of long-term safety and low toxicity for a very long time. Torreya nucifera is widespread in southern Korea and Jeju Island and its seeds are commonly used as edible food. Oriental ingredients have often been reported for their insecticidal, antioxidant and antibacterial properties, but there have not yet been any studies on their antidiabetic effect. In this study, we investigated several biological activities of T. nucifera pericarp (TNP) and seeds (TNS) extracts and proceeded to characterize the antidiabetic compounds of TNS. The initial results suggested that TNS extract at 15 and 10 ㎍/ml concentration has inhibitory effects on α-glucosidase and protein tyrosine phosphatase 1B, that is 14.5 and 4.35 times higher than TNP, respectively. Thus, the stronger antidiabetic TNS was selected for the subsequent experiments to characterize its active compounds. Ultrafiltration was used to determine the apparent molecular weight of the active compounds, showing 300 kDa or more. Finally the mixture was then partially purified using Diaion HP-20 column chromatography by eluting with 50~100% methanol. Therefore we concluded that the active compounds of TNS have potential as therapeutic agents in functional food or supplemental treatment to improve diabetic diseases.

• Microbiology and Biotechnology Letters
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• v.35 no.4
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• pp.339-346
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• 2007

The MJP1 bacterial strain, which possesses antifungal activity, was isolated from meju and identified as Bacillus subtilis based on its morphological and biochemical properties, as well as its 16S rRNA sequence. Antimicrobial activity was found against various species of Gram-positive bacteria, yeasts, and molds, including food-spoilage microorganisms. The antifungal activity was found to be stable after heat and proteolytic enzyme treatment, and in the pH range of $6.0{\sim}10.0$. The antibacterial activity was stable in the pH range of $6.0{\sim}10.0$, but about 50% of the activity was lost after 24 hr at $30^{\circ}C$. The antibacterial compound was also inactivated by proteolytic enzyme treatment, indicating its proteinaceous nature. The apparent molecular masses of the partially purified antifungal and antibacterial compounds, as indicated by using the direct detection method in Tricine-SDS-PAGE, were approximately 2.4 kDa and 4.5 kDa, respectively. These studies suggest that B. subtilis MJP1 produces two bacteriocin-like substances with antifungal and antibacterial activities.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2000.10a
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• pp.9-12
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• 2000

• Journal of Life Science
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• v.33 no.10
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• pp.783-790
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• 2023

Modern people have an increased incidence of metabolic diseases due to changed eating habits, and diabetes is considered the most significant metabolic disease. Given that existing diabetes treatments are accompanied by side effects, the aim of this study was to identify traditional natural products that have anti-diabetic activity. The potential anti-diabetic and antioxidant activities of natural products were examined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay, α-glucosidase assay, and protein tyrosine phosphatase 1B (PTP1B) inhibition assay. Methanol extracts of Ulmus davidiana var. japonica, Acer tegmentosum branches, Nelumbo nucifera seeds, and Carthamus tinctorius seeds were found to have high anti-diabetic activity and further fractionated with solvents using ethyl acetate and butanol. Consequently, the ethyl acetate fraction of C. tinctorius seeds (MG-11-E) with high α-glucosidase and PTP1B inhibitory activity was selected. MG-11-E was subjected to preparative thin layer chromatography, and fraction #6 showed high α-glucosidase and PTP1B inhibitory activity. Fraction #6 was analyzed and fractionated via high performance liquid chromatography with 50% methanol as the mobile phase, and anti-diabetic activity was observed in the sample that eluted after 4 min as a single peak. The α-glucosidase inhibitory activity exhibited by this sample seemed to be greater than the PTP1B inhibitory activity; thus, it was concluded that a greater anti-diabetic therapeutic effect may be achieved by combining this agent with natural products that inhibit PTP1B activity.