• Natural Product Sciences
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• v.26 no.2
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• pp.158-164
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• 2020

Helicobacter pylori is a well-known pathogen that is responsible for gastric disorders. Overcoming of the antibiotic-resistance is a main barrier to treat H. pylori infection. In our search for anti-H. pylori compounds from natural resources, bioactivity-guided isolation on the ethyl acetate fraction of Fraxinus mandshurica bark that had shown anti-H. pylori activity gave twelve compounds (1 - 12) of six coumarins, three phenylethanoids, two secoiridoids, and a lignan using silica gel column chromatography, Sephadex-LH 20, and recrystallization. The chemical structures were identified by spectroscopic data analysis, including 1D, 2D NMR, and mass spectrometry. Among them, compounds 2, 10, and 11 showed moderate growth inhibitory activity against three strains of H. pylori, compared with positive controls of quercetin and metronidazole. Compounds 5, 6, 8, and 12 exhibited the inhibitory activity against strains 26695 or 43504. This is the first report on the anti-H. pylori activity of this plant and the isolated compounds.

• Journal of the Korean Wood Science and Technology
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• v.33 no.5 s.133
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• pp.86-91
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• 2005

Six compounds were isolated from the EtOAc and $Et_2O$ fractions of the bark of Rhus chinensis by repeated column chromatography with $SiO_2$ and Sephadex LH-20. The structures were determined by instrumental analysis using MS and NMR spectrophotometer as: gallic acid (1), methyl gallate (2), 6, 7-dimethoxycoumarin (3), orcinol-${\beta}$-D-glucoside (4), scopoletin (5), semialactone (6). Among these compounds, 6,7-dimethoxycoumarin (3) was isolated from this plant for the first time. To measure the antioxidant activity, the DPPH radical scavenging activity test was performed. Gallic acid (1) showed the strongest activity, while orcinol-${\beta}$-D-glucoside (4), semialactone (5) and scopoletin (6) had the low activities.

• Journal of the Korean Wood Science and Technology
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• v.43 no.5
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• pp.591-599
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• 2015

Cercidiphyllum japonicum leaves were collected, air-dried and extracted with 70% aqueous acetone, then concentrated and sequentially fractionated using n-hexane, methylene chloride ($CH_2Cl_2$), ethylacetate (EtOAc), and $H_2O$. A portion of EtOAc fraction (10 g) was chromatographed on a Sephadex LH-20 column, by the successively elution with various aqueous $MeOH-H_2O$ (1:9, fraction $1-2{\rightarrow}3:7$, fraction $3-5{\rightarrow}1:1$, fraction $6-9{\rightarrow}7:3$, fraction $10-13{\rightarrow}9:1$, fraction 14-16). Compound 2 was isolated from fraction 6 and compound 1 was separated from fraction 11 and 12. Compound 3 and 4 were purified from fraction 13. The isolated compounds were elucidated as quercetin-3-O-${\alpha}$-L-rhamnopyranoside (1), chlorogenic acid (2), quercetin-3-O-${\alpha}$-L-arabinofuranoside (3) and quercetin-3-O-${\beta}$-D-xylopyranoside (4) by the spectral and literature data, and by comparison with the authentic samples. These compounds were reported, for the first time, from the extracts of C. japonicum leaves. Also chlorogenic acid (2) has never been reported before in domestic tree species and can be used as an index compound for C. japonicum.

• Journal of Food Hygiene and Safety
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• v.15 no.2
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• pp.122-127
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• 2000

An antifungal bacterium was isolated to inhibit of the growth of Asp. flavus and Asp. parasiticus, and its antifungal compounds were purified from lyophilized culture broth using chromatographic methods. Antifungal bacterium #19 which was shown a higher inhibitory activity on the growth of aflatoxin producing fungi was identified as Bacillus subtilis. The purified antifungal compound(1 mg) was demonstrated strong antifungal activity against the aflatoxin producing fungi.

• Journal of Microbiology and Biotechnology
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• v.7 no.1
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• pp.56-61
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• 1997

A strain producing immunosuppressive substances was isolated from a soil in Cheju island. By morphological, cultural, and physiological studies, the strain was identified as Streptomyces lydicus MCY-524. Cultured broth was purified by silica gel, sephadex LH-20 and preparative HPLC and gave two immunosuppressive compounds, MCH-22 and MCH-32. They dramatically suppressed the B cell activation with lipopolysaccharide, T cell activation by mixed lymphocyte response, and primary T-dependent antibody response at a final concentration of 1 ${\mu}g$/ml. They also markedly suppressed the proliferation of lymphocytes induced by lipopolysaccharide, pokeweed mitogen, and concanavaline A at the same concentration. Their suppressive activities, which were comparable to those of cyclosporin A, suggested that they were potent and broad immunotoxic agents on the immune functions of murine lymphocytes.

• Microbiology and Biotechnology Letters
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• v.24 no.1
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• pp.82-86
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• 1996

Three thousand microbial strains collected from different sources were screened for herbicidal activity. A strain of ME-9189 showed herbicidal activity against Digitaria sanguinalis and Portulaca oleracea was isolated from a mountainy soil. Based on taxonomic studies, the strain was identified as Streptomyces tubercidicus. The active compound of ME-9189 was purified from the culture broth by charcoal, silica gel, sephadex LH-20 column chromatography and crystalization, consecutively. The ME-9189 compound was identified as tubercidin by spectroscopic methods of UV, $^{1}H$ and $^{13}C$-NMR, and EIMS. In the bioassay, growth of radish shoot and root was inhibited by 50% with tubercidin treatment of 10 ppm, showing 2 times higher activity than that of herbicidin A and similar to that of toyocamycin.

• Fisheries and Aquatic Sciences
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• v.14 no.4
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• pp.283-288
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• 2011

The jellyfish Nemopilema nomurai was hydrolyzed with papain and a novel dipeptide purified via ultrafiltration, gel filtration chromatography with Sephadex LH-20, and reverse phase chromatography using $C_{18}$ and $C_{12}$ columns. The IR, 1H NMR, 13C NMR, and MS spectrometer analyses showed that the dipeptide comprised tyrosine-isoleucine (Tyr-Ile). The $IC_{50}$ and $K_i$ values were $6.56{\pm}1.12$ and $3.10{\pm}0.28\;{\mu}M$, respectively, indicating competitive inhibition of angiotensin-I-converting enzyme (ACE). As a novel ACE-inhibitory active peptide, Tyr-Ile may have potential for use in antihypertensive therapy.

• Journal of the Korean Wood Science and Technology
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• v.44 no.4
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• pp.551-558
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• 2016

Katsura tree (Cercidiphyllum japonicum Sieb. Et Zucc) bark was collected, air-dried and extracted with 70% aqueous acetone, then concentrated and sequentially fractionated using n-hexane, methylene chloride ($CH_2Cl_2$), ethylacetate (EtOAc), and $H_2O$. The $H_2O$ fraction was chromatographed on a Sephadex LH-20 column with various aqueous MeOH eluting solvents to isolate an ellagitannin. The isolate was elucidated as macabarterin, a polyoxygenated ellagitannin by NMR analysis, including HSQC, HMBC, Q-TOF MS, and with the comparison of authentic literature data. The compound was an ellagitannin which was isolated, for the first time, from the extracts of Katsura tree bark, and has never been reported before in domestic tree or plant sources.

• Journal of the Korean Wood Science and Technology
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• v.44 no.4
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• pp.559-570
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• 2016

The EtOAc and $H_2O$ soluble fractions of Katsura tree (Cercidiphyllum japonicum Sieb. Et Zucc) bark extracts were chromatographed on a Sephadex LH-20 column with various aqueous MeOH. Gallic acid (1), methyl galate (2), kurigalin (3), 1,2,3,6-tetra-O-galloyl-${\beta}$-D-glucose (4) and 1,2,3,4,6-penta-O-galloyl-${\beta}$-D-glucose (5) were isolated from EtOAc fraction. Isocorilagin (6) and methyl galate (2) were separated from $H_2O$ fraction. The structure determination was done by $^1H$ and $^{13}C$ NMR. Of these isolated compounds, methyl galate (2), kurigalin (3) and isocorilagin (6) were isolated, for the first time, from the bark extracts of Cercidiphyllum japonicum.

• Archives of Pharmacal Research
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• v.26 no.5
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• pp.367-374
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• 2003

In the course of screening neuraminidase inhibitors from herbal medicines, Reynoutria elliptica exhibited high inhibitory activity. Four active compounds were isolated from the ethyl acetate soluble fraction by consecutive purification using sillica gel, Sephadex LH-20 chromatography, and recrystallization. The chemical structures of these compounds were identified as 1,3,8-trihydroxy-6-methylanthraquinone (emodin) 1,8-dihydroxy-3-methoxy-6-methylanthraquinone (emodin 3-methyl ether; physcion), 1,3,8-trihydroxy-6-hydoxymethylanthraquinone ($\omega$-hydroxyemodin), and 3,5,4 -trihydroxystilbene (trans-resvertrol) by spectral data including MS, $^1 H-, and ^{13}C-NMR. The IC_{50}$ values of emodin, emodin 3-methyl ether, $\omega$-hydroxyemodin, and trans-resvertrol were 2.81, 74.07, 10.49, and 8.77 $\mu$M, respectively. They did not inhibit other glycosidase such as glucosidase, mannosidase, and galactosidase, indicating that they were relatively specific inhibitors of neuraminidase.