• Applied Biological Chemistry
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• v.48 no.3
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• pp.280-284
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• 2005

Several biological activities of Rhododendron mucronulatum were investigated. The electron donating abilities of ethanol extracts of Rhododendron mucronulatum were more than 90% at 100 ppm, 500 ppm and 1,000 ppm. Xanthine oxidase was inhibition about 46% by the ethanol extracts of R. mucronulatum at 500 ppm 48% of tyrosinase activity relating to skin-whitening was shown at 1,000 ppm. Uniquely, the anti-microbial effects of water extract and ethanol extract were shown only on Staphylococcus aureus. The water extract 1 mg/disc showed the higher activity than ethanol extract. The growth inhibition effect of each sample on lung cancer (A549) and melanoma (B16F10) cell lines were over 70% at 1,000 ppm, while the effects on the melanoma (G361) and liver cancer (HepG2) were about 50% at the same concentration.

• Preventive Nutrition and Food Science
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• v.16 no.1
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• pp.29-36
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• 2011

The purpose of this study was to investigate the phytochemical contents and biological activities, including $\alpha$-glucosidase inhibitory activity and antioxidant activity, from the fruits of Elaeagnus multiflora using different solvent systems. The 50% ethanol extract of this species showed the most potent $\alpha$-glucosidase inibitory activity (88.5%) at a concentration of 1 mg/mL. Moreover, this extract also displayed the strongest antioxidant activity in each assay, showing 96.3% in DPPH scavenging activity, 98.2% in ABTS scavenging activity, and 2.5% in reducing power. The highest total phytochemical contents, including flavan-3-ols, phenolic acids, and flavonoids, were observed in the 50% ethanol extract. Interestingly, flavan-3-ols (3.150 mg/g) were detected at a significantly higher total content than those of phenolic acids (0.380 mg/g) and flavonoids (not detected). Additionally, the contents of individual phytochemicals showed remarkable differences, especially the epicatechin gallate (2.008 mg/g) and gallic acid (0.099 mg/g), which were the predominant constituents of each phytochemical type. Therefore, our results suggest that the 50% ethanol extract of E. multiflora fruits has strong biological activities, which are correlated with high phytochemical contents.

• Journal of Physiology & Pathology in Korean Medicine
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• v.30 no.6
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• pp.397-401
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• 2016

The quality control is a fundamental procedure for the standardization of herbal medicine to guarantee the consistency of efficacy and safety. For a long time, the quality analysis of herbal medicine has been largely dependent on the routine sensory evaluation, such as taste, smell, color, and shape. However, with the recent development of analytical instruments, various scientific approaches have been introduced in this field. On the basis of the theory that the biological activities of herbal medicine are mainly contributed by its chemical compositions, several types of chemical markers have been suggested for the quality evaluation. In addition to the analytical methods for the specific marker compound(s), including analytical marker and active marker, recently, chemical fingerprinting, a method comparing the chromatographic pattern of the whole chemical components, has been developed and widely accepted as a reliable approach for the quality control of herbal medicine. Moreover, in order to exactly understand the relationship between complex compounds and their holistic biological activities in herbal medicine, unique strategies, such as "BECCs (bioactive equivalent combinatorial components)" and "PhytomicsQC" have been established. In this article, we give an overview of the several categories of chemical markers and the recent research trends for the quality evaluation of herbal medicine.

• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.3
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• pp.199-204
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• 2003

Among 59 Korean isolated, 20 were confirmed as members of the genus Bifidobaferium species based on gram staining, microscopic examination of cell morphology and the TLC method, The oxygen tolerance and antioxidative activities of these 20 Bifidobacterium strains and 5 standard Bifidobaferium strains were tested. All the strains demonstrated antioxidative activities as regards inhibiting linoleic acid peroxidation. The antioxidative activities of isolated and standard strains were found to range from 10.7-46.4% and from 10.7-22.2%, respectively. In addition, all tested strains exhibited a Scavenging ability on DPPH free radicals, range from 15-41% for the isolated strains and 8.3-22% for the standard strain. Accordingly. the isolated Bifidobarterium strains demonstrated higher antioxidative artivities than the 5 standa rd Bifidobarterium strains. On the base of grades for each test, HJL 7511 was identified 35 the best strain, followed by HJL 7501. 2 strains were identified with Polymerase Chain Reaction (PCR) assay using group-specific primers designed from the nucleotide Sequences of the 16S rRNA and internal transcribed spacer (ITS) regions of the Bifidobacteria. Based on the Sequencing results, HJL 7511 and HJL 7501 were identified as Bifidobacterium infantis.

• The Korean Journal of Mycology
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• v.51 no.4
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• pp.265-276
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• 2023

This study aimed to isolate and characterize fungi from freshwater environments in South Korea and evaluate their extracellular enzyme activities. Fungal strains were collected from various freshwater sources and identified using phylogenetic analysis. The isolated fungi included known aquatic hyphomycetes and previously unreported species. Extracellular enzyme, including those of protease, amylase, lipase, cellulase, laccase, and chitinase, activities were evaluated. Among the isolated strains, several showed high enzyme activity, suggesting their potential role in organic matter decomposition in freshwater ecosystems. This research expands our knowledge of the diversity and enzyme activities of the fungi in freshwater environments, contributing to our understanding of their ecological roles.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.380.2-380.2
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• 2016

The emergence of new infectious diseases, the resurgence of several infections that appeared to have been controlled and the increase in bacterial resistance have created the necessity for studies directed towards the development of new antimicrobials. In the present study, we have synthesized a novel antioxidant ZnO nanoparticle that is newly designed and prepared by simple surface modification process. Antioxidative functionality is provided by the immobilization of antioxidant 3-(3,4-dihydroxyphenyl)-2-propenoic acid (caffeic acid, CA) onto the surface of ZnO nanoparticles. Microstructure and physical properties of the ZnO@CA nanoparticles were investigated by field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), infrared spectroscopy (IR) and steady state spectroscopic methods. Antimicrobial Activities of ZnO@CA nanoparticles were measured against various bacterial strains using antibacterial testing methods.

• Preventive Nutrition and Food Science
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• v.14 no.3
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• pp.195-200
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• 2009

This study was carried out to investigate the biological activities of star anise extracts obtained from four different solvents (water, methanol, ethanol and chloroform) by measuring total polyphenol and flavonoid contents, DPPH radical scavenging, hydroxyl radical scavenging, nitrite scavenging activity and antimicrobial activity. The methanol extract showed the highest extraction yield, followed by ethanol, water and chloroform. The properties of the extracting solvents significantly affected the total polyphenol content. Methanol extracts contained more total polyphenols than any other extracts. The highest DPPH radical scavenging activity was found in methanol extract. The hydroxyl radical and nitrite scavenging activity were highest in methanol and ethanol extracts. In antimicrobial activity, water extract showed stronger activities than methanol and ethanol extract against Micrococcus luteus and Bacillus subtilis, and no inhibitory effects on Gram negative bacteria were found in all extracts at the concentration used.

• Natural Product Sciences
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• v.3 no.1
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• pp.1-7
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• 1997

Eucalyptus is a rich source of biologically active compounds. Among these, phloroglucinol compounds such as sideroxylonals, macrocarpals, euglobals, and robustadials are unique to Eucalyptus species. Sideroxylonal A is a very potent attachment-inhibitor. Macrocarpals show very strong antibacterial activity against gram positive bacteria. Macrocarpals also show HIV-RTase inhibitory activity. Euglobals are potent inhibitors of Epstein-Barr virus activation and are developed as skin and antitumor agents. They also show granulation inhibitory activity. In this review we aim to remove the existing confusion in literature on macrocarpals and discuss the biological activities and structure-activity relationships of phloroglucinol compounds.

• Journal of Marine Bioscience and Biotechnology
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• v.1 no.4
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• pp.225-231
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• 2006

The secondary metabolites from Taiwanese marine soft corals and sponges have attracted much attention because they possess considerable potential biological activities. To explore the origin of bioactivity, many cytotoxic natural products were isolated and characterized in the past few years. For examples, The lipophilic extracts from marine sponges Petrosia elastica and Ircinia formosana were found active against several human tumor cells. The investigation of the gorgonian Junceela has also resulted in the discovery of a series of new juncenolides. Bioassay-directed fractionation of Clavularia viridis yielded seven new prostanoids. These compounds have been tested and evaluated as potential antitumor agents. The soft corals of the genus Cespitularia produced novel secondary metabolites with diverse chemical structures and interesting biological activities. Four new norditerpenoids, designated cespitulactones and cespihypotins were isolated from Cespitularia hypotentaculata. Cespitulactones are novel structures having a bond cleavage between C-10 and C-11. In addition, three novel diterpenes were isolated from C. taeniata and designated cespitulactams A, B and C having a phenylethyl amino side chain.

• Animal cells and systems
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• v.5 no.3
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• pp.195-198
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• 2001

Hepatitis B virus (HBV) polymerase, which possesses the activities of terminal binding, DNA polymerase, reverse transcriptase and RNaseH, has been shown to accomplish viral DNA replication through a pregenomic intermediate. Because the HBV polymerase has not been purified, the expression of HBV polymerase was examined in an E. coli expression system that is under the regulation of arabinose operon. The expressed individual domain containing terminal binding protein, polymerase, or RNaseH turned out to be insoluble. The activities of those domains were not able to be recovered by denaturation and renaturation using urea or guanidine-HCI. The expressed reverse transcriptase containing the polymerase and RNaseH domains became extensively degraded, whereas the proteolysis was reduced in a Ion- mutant. These results indicate that Lon protease proteolyzes the HBV reverse transcriptase expressed in E. coli.