• Mycobiology
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• 제36권3호
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• pp.173-177
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• 2008

The crude ethanol extracts (stem and fruits), their fractions and two triterpenes, $\beta$-Amyrin and 12-Oleanene 3$\beta$, 21$\beta$-diol, isolated as a mixture from the chloroform soluble fraction of an ethanolic extract of Duranta repens stem, were evaluated for antibacterial, antifungal activities by the disc diffusion method and cytotoxicity by brine shrimp lethality bioassay. The structures of the two compounds were confirmed by IR, $^1H$-NMR, $^{13}C$-NMR and LC-MS spectral data. The chloroform soluble fraction of stem and ethanol extract of fruits possess potent antishigellosis activity and also exhibited moderate activity against some pathogenic bacteria and fungi but the isolated compound 1 (mixture of $\beta$-Amyrin and 12-Oleanene 3$\beta$, 21$\beta$-diol) showed mild to moderate inhibitory activity to microbial growth. The minimum inhibitory concentrations (MICs) of the extracts (stem and fruits), their fractions and compound 1 were found to be in the range of 32$\sim$128 ${\mu}g/ml$. The chloroform soluble fractions of stem and ethanol extract of fruit showed significant cytotoxicity with $LC_{50}$ value of 0.94 ${\mu}g/ml$ and 0.49 ${\mu}g/ml$, respectively against brine shrimp larvae.

• Journal of Microbiology and Biotechnology
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• 제15권6호
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• pp.1258-1266
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• 2005

The present study was carried out in order to assess the protective effects of calycosin-7-O-$\beta$-D-glucopyranoside, isolated from Astragali radix (AR), on hyaluronidase (HAase) and the recombinant human interleukin-$1\beta$ (IL-$1\beta$)-induced matrix degradation in human articular cartilage and chondrocytes. We isolated the active component from the n-butanol soluble fraction of AR (ARBu) as the HAase inhibitor and structurally identified as calycosin-7-O-$\beta$-D-glucopyranoside by LC-MS, IR, ${1}^H$ NMR, and ${13}^C$ NMR analyses. The $IC_{50}$ of this component on HAase was found to be 3.7 mg/ml by in vitro agarose plate assay. The protective effect of ARBu on the matrix gene expression of immortalized chondrocyte cell line C28/I2 treated with HAase was investigated using a reverse transcription polymerase chain reaction (RT-PCR), and its effect on HAase and IL-$1\beta$-induced matrix degradation in human articular cartilage was determined by a staining method and calculating the amount of degraded glycosaminoglycan (GAG) from the cultured media. Pretreatment with calycosin-7-O-$\beta$-D-glucopyranoside effectively protected human chondrocytes and articular cartilage from matrix degradation. Therefore, calycosin-7-O-$\beta$-D-glucopyranoside from AR appears to be a potential natural ant-inflammatory or antii-osteoarthritis agent and can be effectively used to protect from proteoglycan (PG) degradation.

• Food Science and Biotechnology
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• 제14권2호
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• pp.263-267
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• 2005

In order to isolate hyaluronidase (HAase) inhibitor from Astragali radix (AR), dried roots were extracted with ethanol, prior to sequential fractionations with n-hexane, chloroform, ethyl acetate, n-butanol, and aqueous fractions. The n-butanol soluble fraction was found to exhibit the most pronounced inhibitory effect (68%) on HAase, and the active components were separated using various chromatographic methods, including column chromatography and preparative HPLC. The active component was isolated from the n-butanol soluble fraction of AR and was structurally identified as calycosin-7-O-${\beta}$-D-glucopyranoside by LC-MS, IR, $^1H$ NMR, and $^{13}C$ NMR analysis. The $IC_{50}$ of calycosin-7-O-${\beta}$-D-glucopyranoside's HAase activity was found to be 3.7 mg/mL.

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2006년도 추계 학술발표회 발표논문집
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• pp.285-289
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• 2006

In screening of algicidal bacteria, we isolated a marine bacterium which had potent algicidal effects on harmful algal bloom (HAB) species. This organism was identified as a strain very close to Bacillus subtilisby 16S rRNA gene sequencing. This bacterium, Bacillus sp. SY-1, produces very active algicidal compounds against the harmful dinoflagellate Cochlodinium polykrikoides. We isolated three algicidal compounds (MS 1056, 1070, 1084) and identified them by amino acid analyses, fast atom bombardment mass spectrometry (FAB-MS), infrared spectroscopy (IR), $^1H$, $^{13}C$, and extensive two-dimensional nuclear magnetic resonance (2D NMR) techniques including $^1H-^{15}N$ HMBC analysis. One of them, MS 1056, contains a b-amino acid residue with an alkyl side chain of $C_{15}$. MS 1056, 1070, and 1084 showed algicidal activities against C. polykrikoides with an $LC_{50}$ (6 hrs) of 2.3, 0.8, $0.6\;{\mu}g/ml$, respectively. These compounds also showed significant algicidal activities against other harmful dinoflagellates and raphidophytes. In contrast, MS 1084 showed no significant growth inhibition against various organisms coexisting with HAB species in natural environments, including bacteria, eukaryotic microalgae, and cyanobacteria, although it inhibited growth of some fungi and yeasts. These observations imply that algicidal bacterium Bacillus sp. SY-1 and its algicidal compounds could play an important role in regulating the onset and development of HABs in the natural environments.

• Journal of Microbiology and Biotechnology
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• 제17권3호
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• pp.403-407
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• 2007

Several marine. bacterial strains, which were isolated from seawater off the island Dokdo, Korea, were screened to find new bioactive compounds such as antibiotics. Among them, Donghaeana dokdonensis strain DSW-6 was found to produce antibacterial agents, and the agents were then purified and analyzed by LC-MS/MS and 1D- and 2D-NMR spectrometries. The bioactive compounds were successfully identified as cholic acid and glycine-conjugated glycocholic acid, the $7{\alpha}$-dehydroxylated derivatives (deoxycholic acid and glycodeoxycholic acid) of which were also detected in relatively small amounts. Other marine isolates, taxonomically different from DSW-6, were also able to produce the compounds in a quite different production ratio from DSW-6. As far as we are aware of, these bile acids are produced by specific members of the genus Streptomyces and Myroides, and thought to be general secondary metabolites produced by a variety of bacterial taxa that are widely distributed in the sea.

• Biomolecules & Therapeutics
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• 제25권6호
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• pp.559-568
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• 2017

Metabolomics has been used as a powerful tool for the analysis and quality assessment of the natural product (NP)-derived medicines. It is increasingly being used in the quality control and standardization of NP-derived medicines because they are composed of hundreds of natural compounds. The most common techniques that are used in metabolomics consist of NMR, GC-MS, and LC-MS in combination with multivariate statistical analyses including principal components analysis (PCA) and partial least squares-discriminant analysis (PLS-DA). Currently, the quality control of the NP-derived medicines is usually conducted using HPLC and is specified by one or two indicators. To create a superior quality control framework and avoid adulterated drugs, it is necessary to be able to determine and establish standards based on multiple ingredients using metabolic profiling and fingerprinting. Therefore, the application of various analytical tools in the quality control of NP-derived medicines forms the major part of this review. $Veregen^{(R)}$ (Medigene AG, Planegg/Martinsried, Germany), which is the first botanical prescription drug approved by US Food and Drug Administration, is reviewed as an example that will hopefully provide future directions and perspectives on metabolomics technologies available for the quality control of NP-derived medicines.

• Journal of Microbiology and Biotechnology
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• 제21권9호
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• pp.930-936
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• 2011

Two new cyclic depsipeptides wewakamide A (1) and guineamide G (2) have been isolated from the marine cyanobacterium Lyngbya semiplena and Lyngbya majuscula, respectively, collected from Papua New Guinea. The amino and hydroxy acid partial structures of wewakamide A and guineamide G were elucidated through extensive spectroscopic techniques, including HR-FABMS, 1D $^1H$ and $^{13}C$ NMR, as well as 2D COSY, HSQC, HSQC-TOCSY, and HMBC spectra. The sequence of the residues of wewakamide A was determined through a combination of ESI-MS/MS, HMBC, and ROESY. Wewakamide A possesses a ${\beta}$-amino acid, 3-amino-2-methylbutanoic acid (Maba) residue, which has only been previously identified in two natural products, guineamide B (3) and dolastatin D (4). Although both new compounds (1,2) showed potent brine shrimp toxicity, only guineamide G displayed significant cytotoxicity to a mouse neuroblastoma cell line with $LC_{50}$ values of 2.7 ${\mu}M$.

• Bulletin of the Korean Chemical Society
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• 제32권10호
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• pp.3650-3654
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• 2011

Two new unusual soyasaponins named 6"-O-methyldehydrosoyasaponin I(7) and desglucosylsoyasaponin $A_1$ (10) along with eight known saponins, dehydrosoyasaponin IV (1), dehydrosoyasaponin III (= impatienoside A) (2), soyasaponin III (3), dehydrosoyasaponin II (= soyasaponin Bg) (4), soyasaponin II (5), dehydrosoyasaponin I (= soyasaponin Be) (6), soyasaponin I (8), and kudzusaponin $SA_3$ (9), were isolated as their methyl esters and identified from the liquid culture of G. applanatum. Their structures were determined by chemical and spectroscopic analyses including 1D- and 2D-NMR as well as by comparison of their spectroscopic data with those of the reported in literatures. Although dehydrosoyasaponin IV was identified by LC-MS/MS method from soy protein isolate, this is the first report of the isolation of this compound. Dehydrosoyasaponin III (2) and kudzusaponin $SA_3$ (9) were also isolated for the first time from soybean. The presence of soyasaponins in Ganoderma species seems to be unusual feature. Thus, we presumed that compounds 1-10 might all be derived from the defatted soybean flour which was added to the culture medium as a nitrogen source.

• Journal of Applied Biological Chemistry
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• 제62권1호
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• pp.81-86
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• 2019

A yellow resin (gamboge) from Garcinia hanburyi has been widely used as folk medicine due to its antibacterial and antitumor activities. We isolated four ${\alpha}$-glucosidase inhibitory compounds from the methanol extract of gamboge. The compounds (1-4) were identified as gambogoic acid (1), moreollic acid (2), gambogic acid (3), and 10-methoxygambogenic acid (4), respectively through spectroscopic data including 2D-NMR and HREIMS. All compounds were examined in the enzyme inhibition assay against ${\alpha}$-glucosidase to identify their inhibitory potencies and kinetic behavior. All compounds (1-4) showed enzyme inhibition against ${\alpha}$-glucosidase, but the activity was significantly affected by the methoxy group on C-10 of ring A and pentenyl pyran moiety of ring D. For example, compound 1 ($IC_{50}=41.4{\mu}M$) bearing pyran ring eight times effective that 4 ($IC_{50}=350.6{\mu}M$) having geranyl group itself. Most active compound was found out to be gambogoic acid (1) which was analyzed most abundant metabolite in gamboge by LC-ESI-MS/MS. In kinetic study, compounds 1 and 2 were proved as noncompetitive inhibitors.

• 약학회지
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• 제54권4호
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• pp.240-243
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• 2010

High-performance liquid chromatography (HPLC) screening method revealed that a propolis product marketed as a functional food contained an undeclared substance similar to tadalafil, the active ingredient of the prescription drug Cialis$^{(R)}$ approved for the treatment of male erectile dysfunction. In order to identify the illegal additive, the propolis product was extracted with methylene chloride, and the extract was purified further using semipreparative HPLC. The chemical structure of the isolated substance was elucidated based on IR, LC/MS-ESI, and $^1H$- and $^{13}C$-NMR spectroscopy, which showed the characteristics similar to tadalafil. The only difference was the substitution of the methyl group at the piperazinedione ring of tadalafil to the amino group of the identified illegal additive.