• Natural Product Sciences
• /
• v.22 no.3
• /
• pp.220-224
• /
• 2016

Anti-Helicobacter pylori activity guided fractionation led to the isolation of five anthraquinones, two stilbenes and one naphthoquinone from the EtOAc fraction of Polygonum cuspidatum, using silica gel column chromatography, Sephadex-LH20, MPLC and recrystallization. The chemical structures were identified to be physcion (1), emodin (2), anthraglycoside B (3), trans-resveratrol (4), anthraglycoside A (5), polydatin (6), 2-methoxy-6-acetyl-7-methyljuglone (7) and citreorosein (8) by UV, $^1H$-NMR, $^{13}C$-NMR and mass spectrometry. Anti-Helicobacter pylori activity including MIC values of each compound was evaluated. All of the isolates exhibited anti-H. pylori activity of which MIC values were lower than that of a positive control, quercetin. Compounds 2 and 7 showed potent growth inhibitory activity. Especially, a naphthoquinone, compound 7 displayed most potent antibacterial activity with $MIC_{50}$ value of $0.30{\mu}M$ and $MIC_{90}$ value of $0.39{\mu}M$. Although anti-H. pylori activity of this plant was previously reported, this is the first report on that of compounds isolated from this species. From these findings, P. cuspidatum roots or its isolates may be useful for H. pylori infection and further study is needed to elucidate mechanism of action.

• Proceedings of the Korean Society of Applied Pharmacology
• /
• 1998.11a
• /
• pp.159-160
• /
• 1998

Results of chemistry and biological activity of many years indicate that plants belonging to the Isodon genus are rich in ent-kaurane diterpenoids, which have been revealed to possess biological activities such as antitumor, antibacterial and antiinflammatory effects. In continuation of our research on diterpenoids in medicinal plants of this genus, the acetone extract from the leaves of I. xerophilus, which is a plant native to Yunnan province of China, showed potent antitumor activity against K562. After partition, the most active EtOAc part was studied. Four new diterpenoids named xerophilusin A(l), B(2), C(3), D(4), and eight known compounds including macrocalin B(5) and rabdorosthomin A(6) were isolated, whose structures were elucidated through a series of one- and two-dimensional NMR techniques(DEPT, COSY, HMQC, HMBC and ROESY experiments). Among them, compound 1, 2 and 5 had two unique epoxy units formed by two ether bridges from C-20 to C-7, C-14. Up to now, there are four compounds having such an peculiar structure besides these three compounds. Compound 3 and 4 were two of the few examples possessing $1{\beta}$ substitutes. All the diterpenoid compounds were subjected to the antitumor screening. It is interesting that only xerophilusin A(l), B(2) and macrocalin(5) exhibited significant antitumor activity against K562 by the method of MTT($IC_{50}$ were listed in Table 1.). The results inspired us to infer that the unique ether bridges from C-20 to C-7, C-14 possibly played an important role in the antitumor activity.

• Archives of Pharmacal Research
• /
• v.29 no.1
• /
• pp.16-25
• /
• 2006

A novel series of 1-(1-benzofuran-2-yl-ethylidene)-4-substituted thiosemicarbazides (2a-d) along with some derived ring systems: substituted-2,3-dihydro-thiazoles(3a-c, 4a-f) and thiazolidin-4-ones(5a-d and 6a-d), were synthesized. In addition, cyanoacetic acid-(1-benzofuran-2-yl-ethylidene) hydrazide(7) was used to prepare another new series of compounds consisting of substituted pyridin-2(1H)-ones(8a-c); 2-thioxo-2,3-dihydro-thiazoles(9a-d) and 2-thioxo-2,3-dihydro-6H-thiazolo[4,5-d]pyrimidin-7-ones (10a-c, 11a-c). The absolute configuration of compound 5c was determined by X-ray crystallography. The compounds prepared were evaluated for their in vitro anti-HIV, anticancer, antibacterial, and antifungal activities. Among the tested compounds, compounds 5c and 9a produced a significant reduction ㅐ ㄹ the viral cytopathic effect (93.19% and 59.55%) at concentrations $>2.0{\times}10^{-4}\;M\;and\;2.5{\times}10^{-5}\;M$respectively. Compound 9a was confirmed to have moderate anti-HIV activity. Compounds 2a, 2d, and 5c showed mild antifungal activity. However, none of the tested compounds showed any significant anticancer activity.

• Archives of Pharmacal Research
• /
• v.29 no.10
• /
• pp.826-833
• /
• 2006

Previously, we synthesized and evaluated several benzofuran derivatives containing heterocyclic ring substituents linked to the benzofuran nucleus at C-2 by a two- to four-atom spacer as potential anti-HIV-1, anticancer and antimicrobial agents. Among these derivatives, NSC 725612 and NSC 725716 exhibited interesting anti-HIV-1 activity. To further investigate the structure-activity relationship, we synthesized several new benzofuran derivatives derived from 2-acetylbenzofuran (2, 3a-c) and 2-bromoacetylbenzofuran (6; 7a,b; 8a,b). The compounds were designed to comprise the heterocyclic substituents directly linked to the benzofuran nucleus at C-2. Moreover, various related benzimidazoles derived from 2-acetylbenzimidazole and from 2-cyanomethylbenzimidazole (12a,b; 13a,b; 15; 16a,b) were also prepared as isosteres. The synthesized compounds were preliminarily evaluated for their in vitro anti-HIV-1, anticancer and antimicrobial activity. Compounds 2, 3a, 3b, and 12b showed weak anti-HIV-1 activity. Compound 6 exhibited mild activity against S. aureus, while compound 15 had mild activity towards S. aureus and C. albicans. However, no significant anticancer activity was observed with any of the tested compounds. From these results, we conclude that the presence of the spacer between the heterocyclic substituent and the benzofuran nucleus may be essential for the biological activity.

• Journal of the Korean Chemical Society
• /
• v.40 no.9
• /
• pp.623-629
• /
• 1996

In order to identify antibiotic substances in the extract of a lichen, Umbilicaria vellea, the extract was chromatographed and two compounds were isolated. Compound I which showed antifungal and antibacterial activities, melted around 129∼132$^{\circ}C$ and showed UV absorption at 217, 265 and 300 nm. It showed a molecular ion at m/z 196. Its molecular formular was confirmed to be $C_{10}H_{12}O_4$ from elemental analysis. From its IR and NMR data it was identified to be ethyl 2,4-dihydroxy-6-methyl benzoate. Compound II melted around 58∼59$^{\circ}C$ and showed UV absorption at 212, 276 and 282 nm. It showed a molecular ion at m/z 124 and molecular formular was confirmed to be $C_7H_8O_2.$ From the analysis of its IR and NMR spectra it was identified to be 5-methyl-1,3-benzenediol.

• Mycobiology
• /
• v.36 no.3
• /
• pp.173-177
• /
• 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.

• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2019.10a
• /
• pp.8-8
• /
• 2019

The stringent response (SR) is characterized as a bacterial defense mechanism in response to various growth-inhibiting stresses. It is activated by accumulation of a small nucleotide regulator, (p)ppGpp, and induces global changes in bacterial transcription and translation. Recent work from our group has shown that (p)ppGpp plays a critical role in virulence and survival in Vibrio cholerae. The genes, relA and relV, are involved in the production of (p)ppGpp, while the spoT gene encodes an enzyme that hydrolyzes it in V. cholerae. A mutant strain defective in (p)ppGpp production (i.e. ${\Delta}relA{\Delta}relV{\Delta}spoT$ mutant) lost the ability to produce cholera toxin (CT) and lost their viability due to uncontrolled production of organic acids, when grown with extra glucose. In contrast, the ${\Delta}relA{\Delta}spoT$ mutant, a (p)ppGpp overproducer strain, produced enhanced level of CT and exhibited better growth in glucose supplemented media via glucose metabolic switch from organic fermentation to acetoin, a neutral fermentation end product, fermentation. These findings indicates that (p)ppGpp, in addition to its well-known role as a SR mediator, positively regulates CT production and maintenance of growth fitness in V. cholerae. This implicates SR as a promising drug target, inhibition of which may possibly downregulate V. cholerae virulence and survival fitness. Therefore, we screened a chemical library and identified a compound that induces medium acidification (termed iMAC) and thereby loss of wild type V. cholerae viability under glucose-rich conditions. Further, we present a potential mechanism by which the compound inhibits (p)ppGpp accumulation. Together, these results indicate that iMAC treatment causes V. cholerae cells to produce significantly less (p)ppGpp, an important regulator of the bacterial virulence and survival response, and further suggesting that it has a therapeutic potential to be developed as a novel antibacterial agent against cholera.

• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2023.04a
• /
• pp.61-61
• /
• 2023

Zanthoxylum piperitum has been used as a spice or various folk remedies since ancient times, and studies on antibacterial, anti-inflammatory and analgesic effects have been reported. In this study, a raw material standardization study was conducted for the industrialization of Z. piperitum. First, optimal conditions for drying methods were established for the standardization of raw materials for Z. piperitum, and optimal conditions were established through content analysis using quercitrin, an marker compound, by obtaining samples every month. As for the drying method of Z. piperitum, it was confirmed that cold air drying was the best. It was analyzed that the marker compound content was highest in July. Next, for functional and toxicity evaluation of Z. piperitum, anti-oxidant, anti-inflammatory and immune enhancing efficacy and cytotoxicity were evaluated. Cytotoxicity of Z. piperitum was not observed, and it was confirmed that although it had an antioxidant and anti-inflammatory effect, it had no immuneenhancing effects. In addition, a study was conducted on the change in the efficacy of Z. piperitum using lava seawater, and as a result of the study, it was confirmed that the efficacy was superior when lava seawater was simultaneously treated. In conclusion, this study suggested the standardization of raw materials through the analysis of the marker compounds and the functional evaluation of Z. piperitum, and it can be used as basic data for future industrialization.

• The Journal of the Korean dental association
• /
• v.55 no.2
• /
• pp.180-188
• /
• 2017

Introduction : Inadequate oral health control is a major risk of oral diseases. Regular home-based care is essential to maintain good oral hygiene. In particular, mouthrinses can support conventional tooth brushing in reducing accumulation of oral plaque. Effect : Antimicrobial mouthrinses are used as part of daily oral care to reduce plaque and gingivitis. Mouthrinses contains fluoride could help remineralization of enamel and dentin. The most common molecules contained in mouthrinses are chlorhexidine, essential oils, cetyl pyridinium chloride, triclosan, hyaluronic acid. Currently, chlorhexidine is the most efficacious compound, with both antiplaque and antibacterial activities. Similar results are reported for essential oils and cetyl pyridinium chloride, although with a somewhat reduced efficacy. Considering the adverse effects of chlorhexidine and its time-related characteristics, this molecule may best be indicated for acute/short term use, while essential oils and cetyl pyridinium chloride may be appropriate for long-term, maintenance treatment. Conclusion and suggestion : Antimicrobial mouthrinses are safe and effective, and when used in conjunction with brushing and flossing, they are an important method of reducing plaque and gingivitis. To improve compliance, dental health care professionals should adapt oral health care recommendations to fit patients' specific needs.

• Journal of the Korean Wood Science and Technology
• /
• v.48 no.6
• /
• pp.888-895
• /
• 2020

Ulmus genus has excellent various physiological activities, including anti-ulcer, antioxidant, antibacterial, anti-cancer, immunity, and homeostasis maintenance effects, and it is known to have many additional drug effects And one of reasons for these excellentbiological activities is a flavan-3-ol chemical group in Ulmus genus. In this study a new flavan-3-ol compound was identified in Ulmus davidiana var. japonica. A flavan-3-ol,(2R,3S)-7-[(2S,3R,4R)-3,4-dihydroxy-4-(hydroxymethyl)oxolan-2-yl]oxy-2-(3,4-dihydroxyphenyl)-3,4-dihydro-2H-chromene-3,5-diol, named as catechin 7-O-beta-D apiofuranoside, was isolated from the stems and barks of Ulmus davidiana var. japonica for. suberosa, which is a species belonging to the genus Ulmus, growing throughout the Korea peninsula. The structure was elucidated by various spectroscopic methods including high-resolution TOF mass spectrometry, ¹H-NMR and ¹³C-NMR spectrometry and comparison with chemical structures of defined compounds.