• Natural Product Sciences
• /
• v.5 no.2
• /
• pp.80-84
• /
• 1999

Peroxynitrite is a cytotoxic intermediate produced by the reaction between the superoxide anion radical and nitric oxide. Flavonoids (afzelin, quercitrin and quercetin 3-O-sambubioside), and chlorogenic acid and its methyl ester obtained from leaves of loquat (Eriobotrya japonica) have recently been shown to scavenge 1,1-diphenyl-2-picrylhydrazyl radical and to inhibit lipid peroxidation in mouse liver homogenate. The aim of this study is to investigate the inhibitory effects of the above components on peroxynitrite produced stimulated by 3-morpholinosydnonimine (SIN-1) to produce superoxide anion radical and nitric oxide at the same time. In addition, the present study tests whether or not the components directly scavenge peroxynitrite itself. The results showed that the components with the aromatic ortho-dihydroxyl groups (catechol) were more potent inhibitors of peroxynitrite formation by SIN-1. In particular, the methyl ester form of chlorogenic acid showed the most potent inhibition. At $5\;{\mu}M$ concentration, the order of minimizing peroxynitrite formation were : methyl chlorogenic acid > quercitrin > quercetin 3-O-sambubioside > chlorogenic acid > afzelin. Authentic peroxynitrite was directly scavenged by the components in a manner similar to peroxynitrite formation by SIN-1. In particular, when compared with penicillamine as a positive control, methyl chlorogenate was as effective in inhibiting peroxynitrite formation and approximately 2 times more effective in scavenging an authentic peroxynitrite. These results demonstrate therefore, that components extracted from the leaves of Eriobotrya japonica effectively scavenged peroxynitrite.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.59 no.4
• /
• pp.435-444
• /
• 2014

This study was carried out to isolate and characterize the flavonoids present in corn silks. Maysin content in the unpollinated corn silks (Kwangpyeongok) showed its highest level at 3 days after silking, and decreased thereafter, while the content of open pollinated silks were consistently decreased after silking. This result indicates that the maysin content is considerably affected by the pollination of corn silk. Unpollinated corn silks were collected with excising, and ethanol employed to extract flavonoids at common temperature for 9 days. After extraction, chlorophyll, lipids etc. were removed with methylene chloride, then submitted to flash column cartridge ($150{\times}40mm$ i.d.) packed with a preparative $RP-C_{18}$ bulk packing material ($125{\AA}$, $55-105{\mu}m$), and monitored at 352 nm. Four fractions, fraction-I, -II, -III, and -IV, were isolated from ethanolic extract of corn silks. Absorption spectrum of fraction I showed its maximum intensity (${\lambda}_{max}$) at 327 nm and 239 nm, fraction-II showed its maximum intensity at 339 nm and 274 nm, fraction-III showed its maximum intensity at 345 nm and 277 nm, and fraction-IV showed its maximum intensity at 352 nm, 270 nm, 257 nm, respectively. On the baisis of ESI micro-TOF analysis, fraction-I was identified as chlorogenic acid (m/z 355, 3-(3,4-dihydroxycinnamoyl) quinic acid, $C_{16}H_{18}O_9$), fraction-II identified as a mixture of chlorogenic acid and luteolin 3'-methyl ether 7-glucuronosyl-($1{\rightarrow}2$)-glucuronide (m/z 653, $C_{28}H_{28}O_{18}$), fraction-III identified as a mixture of chlorogenic acid luteolin 7-O-neohesperidoside (m/z 595, $C_{27}H_{30}O_{15}$), and luteolin 3'-methyl ether 7-glucuronosyl-($1{\rightarrow}2$)-glucuronide, and fraction-IV identified as maysin (m/z 577, 2"-O-${\alpha}$-L-rhamnosyl-6-C-(6-deoxy-xylohexose-4-ulosyl)luteolin, $C_{27}H_{28}O_{14}$), respectively. From the ethanolic extract of corn silks, fraction-I was obtained about 35 mg/100 g F.W., fraction-II was about 48 mg/100 g F.W., fraction-III was about 46 mg/100 g F.W., and fraction-IV was about 138 mg/100 g F.W., respectively.

• Archives of Pharmacal Research
• /
• v.22 no.2
• /
• pp.213-218
• /
• 1999

The antioxidant activity of Eriobotrya japonica was determined by measuring the radical scavenging effect on DPPH (1,1-diphenyl-2-picrylhydrazyl) radical and lipid peroxidation produced when mouse liver homogenate was exposed to the air at $37^{\circ}C$, using 2-thiobarbituric acid (TBA). The methanol extract and its factions of Eriobotrya japonica leaves showed strong antioxidant activity. The antioxidant activity of EtOAc and n-BuOH soluble fractions were stronger than the others, and were further purified by repeated silica gel, MCl gel CHP-20P, and Sephadex LH-20 column chromatography. Antioxidant chlorogenic acid, quercetin-3-sambubioside from n-BuOH fraction and methyl chlorogenate, kaempferol- and quercetin-3-rhamnosides, together with the inactive ursolic acid and$ 2{\alpha}$-hydroxyursolic acid from EtOAc fraction were isolated. Antioxidant flavonoids and chlorogenic acid also showed prominent inhibitory activity against free radical generation in dichlorofluorescein (DCF) method.

• Natural Product Sciences
• /
• v.16 no.1
• /
• pp.20-25
• /
• 2010

Fourteen compounds were isolated from the n-BuOH fraction of the roots of Aralia cordata (syn. = A. continentalis). Through spectroscopic method, the chemical structures were elucidated as: caffeic acid (1), protocatechuic acid (2), thymidine (3), uridine (4), methyl-$\alpha$-D-fructofuranoside (5), a mixture (3 : 1) of $\beta$-D-fructopyranoside and $\beta$-D-fructofuranoside (6), 1-methyl 1,2,3,4-tetrahydro-$\beta$-carboline-3-carboxylic acid (7), methyl-$\beta$-D-fructofuranoside (8), sucrose (9), 5-caffeoylquinic acid (chlorogenic acid) (10), 3-caffeoylquinic acid (neochlorogenic acid) (11), 4-caffeoylquinic acid (cryptochlorogenic acid) (12), 3,5-di-O-caffeoylquinic acid (13), and 1-kestose [$\beta$-D-fructofuranosyl-($2{\rightarrow}1$)-$\beta$-D-fructofuranosyl-($2{\rightarrow}1$)-$\alpha$-D-glucopyranoside] (14). Among them, compounds 5, 7, 8, and 10 - 14 were isolated from this plant for the first time.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.45 no.8
• /
• pp.1208-1213
• /
• 2016

Advanced glycation end product (AGE) formation and reactive oxygen species are potential therapeutic targets for the prevention of diabetic nephropathy and other pathogenic complications. Activity-guided isolation of an ethylacetate-soluble portion of 80% methanolic extract from fruits of Sorbus commixta of the Ulleung Island origin using AGE formation inhibition assay led to the isolation and identification of three caffeoylquinic acid derivatives of a previously known structure, 3-O-caffeoylquinic acid (neochlorogenic acid; 1), 4-O-caffeoylquinic acid (cryptochlorogenic acid; 2), and 5-O-caffeoylquinic acid (chlorogenic acid; 3). The structures of these compounds were confirmed by interpretation of nuclear magnetic resonance and mass spectrometry data. Among the isolates, the major metabolite, neochlorogenic acid (1) showed the most potent inhibitory effect against AGE formation with an $IC_{50}$ value of $167.5{\pm}3.5{\mu}M$. Furthermore, all isolated chlorogenic acid isomers were evaluated for their radical scavenging activity against peroxynitrite, and structurally related isomers 1, 2, and 3 exhibited potent inhibitory effects in this radical scavenging assay. This result suggests that the monocaffeoyl quinic acid derivatives isolated from S. commixta might be beneficial for the regulation of diabetic complications and related diseases.

• Natural Product Sciences
• /
• v.15 no.4
• /
• pp.234-240
• /
• 2009

Phytochemical investigation of the MeOH extract of the aerial parts of Bistorta manshuriensis resulted in the isolation of two cerebrosides, two lactams, six phenolic compounds and seven flavonoids. Their chemical structures were characterized by spectroscopic methods to be pinelloside (1), soyacerebroside I (2), pterolactam (3), 5-hydroxypyrrolidine-2-one (4), vanillic acid (5), caffeic acid methyl ester (6), protocatechuic acid (7), caffeic acid (8), 3,5-di-O-caffeoyl quinic acid methyl ester (9), chlorogenic acid methyl ester (10), avicularin (11), afzelin (12), quercetin (13), isoorientin (14), quercetin 3-O-${\beta}$-D-glucoside (15), quercitrin (16), and luteolin (17). The isolated compounds (1 - 4, 7, 12, 14) were isolated for the first time from this plant source and the compounds 1 - 4, 9 and 10 were first reported from the genus Bistorta. Compound 17 exhibited moderate cytotoxicity and compound 6 exhibited weak cytotoxicity against four human cancer cell lines in vitro using an SRB bioassay.

• Natural Product Sciences
• /
• v.17 no.4
• /
• pp.342-349
• /
• 2011

This study was performed to determine the composition of phenolic substances contained in the leaves of Cirsium setidens (Compositae), validate the high-performance liquid chromatography (HPLC) method, and determine the in vivo sedative effect of the main component pectolinarin. Six phenolic compounds isolated from C. setidens were spectroscopically identified as chlorogenic acid (1), hyperoside (2), 3,4-di-O-caffeoylquinic acid (3), caffeic acid methyl ester (4), linarin (5), and pectolinarin (6) and then used as standard compounds for HPLC analysis. HPLC proved to be precise, accurate, and sensitive for the simultaneous analysis of the phenolic substances. In particular, six compounds showed good regression ($R^2$ > 0.999) within test ranges and recovery was in the range of 95.4 - 104.8%. The content of pectolinarin was considerably higher (156.48 mg/g) than those of other phenolic substances including the other flavone glycoside, linarin (18.99 mg/g). The contents of other phenolic substances, in order, were chlorogenic acid (8.41 mg/g), 3,4-di-O-caffeoylquinic acid (5.74 mg/g), hyperoside (4.33 mg/g), and caffeic acid methyl ester (0.51 mg/g). Oral administration with compound 6 (10 and 20 mg/kg) enhanced the sleeping time induced by pentobarbital in mice, indicating that it has a sedative effect.

• Korean Journal of Plant Resources
• /
• v.20 no.3
• /
• pp.221-225
• /
• 2007

The plant Ligularia fischeri var. spiciformis (Compositae) is a candidate for available functional foods. It has been used to treat diabetes mellitus and rheumatoid arthritis. We have reported the isolation of a new eremophilanolide named 6-oxoeremophilenolide and cytotoxic intermedeol together with the isolation of hydrophilic constituents, chlorogenic acid, 3,4-di-O-caffeoylquinic acie (3), and 5-O-[1-butyl]-3,4-di-O-caffeoylquinic acid. Compound 3 was again isolated by combination of silica gel- and ODS column chromatography for the anti-nociceptive action. Compound 3 and 4 were assayed in hot plate- and writhing tests in the rat. Although the three derivatives of caffeic acid exhibited significant anti-nociceptive effects at 10 mg/kg dose (i.p.),(activity potency: 4>3). These results suggest that compound 3 is responsible for at least rheumatoid arthritis, and caffeic acid moiety is the active moiety of dicaffeoylquinic acid.

• Journal of Integrative Natural Science
• /
• v.10 no.1
• /
• pp.1-6
• /
• 2017

Demand for a new anti-malarial drug has been dramatically increasing in the recent years. Plasmodium falciparum enoyl-acyl carrier protein reductase (PfENR) plays a vital role in fatty acid elongation process, which now emerged as a new important target for the development of anti-microbial and anti-parasitic molecules. In the present study, 19 compounds namely alginic acid, atropine, chlorogenic acid, chrotacumine A & B, coenzyme $Q_1$, 4-coumaric acid, curcumin, ellagic acid, embelin, 5-O-methyl embelin, eugenyl glucoside, glabridin, hyoscyamine, nordihydroguaiaretic acid, rohitukine, scopolamine, tlatlancuayin and ursolic acid were evaluated on their docking behaviour on P. falciparum enoyl-acyl carrier protein reductase (PfENR) using Auto dock 4.2. The docking studies and binding free energy calculations exhibited that glabridin gave the highest binding energy (-8.07 kcal/mol) and 4-coumaric acid in contrast showed the least binding energy (-4.83 kcal/mol). All ligands except alginic acid, ellagic acid, hyoscyamine and glabridin interacted with Gln409 amino acid residue. Interestingly four ligands namely coenzyme $Q_1$, 4-coumaric acid, embelin and 5-O-methyl embelin interacted with Gln409 amino acid residue present in both chains (A & B) of PfENR protein. Thus, the results of this present study exhibited the potential of these 19 ligands as P. falciparum enoyl-acyl carrier protein reductase (PfENR) inhibitory agents and also as anti-malarial agents.

• Korean Journal of Pharmacognosy
• /
• v.47 no.1
• /
• pp.92-101
• /
• 2016

In this study, an ultra-performance liquid chromatography-electrospray ionization-mass spectrometry (UPLC-ESI-MS/MS) method was established for simultaneous determination of the 25 marker components, including chlorogenic acid, gallic acid, oxypaeoniflorin, homogentisic acid, methyl gallate, caffeic acid, 3,4-dihydroxybenzaldehyde, paeoniflorin, albiflorin, liquiritin, nodakenin, ferulic acid, ginsenoside Rg1, liquiritigenin, coumarin, cinnamic acid, benzoylpaeoniflorin, ginsenoside Rb1, cinnamaldehyde, paeonol, glycyrrhizin, 6-gingerol, evodiamine, rutecarpine, and spicatoside A in traditional Korean formula, Onkyung-tang. All analytes were separated on a Waters Acquity UPLC BEH $C_{18}$ analytical column ($2.1{\times}100mm$, $1.7{\mu}m$) at $45^{\circ}C$ using a mobile phase of 0.1% (v/v) formic acid in water and acetonitrile with gradient elution. The MS analysis was carried out using a Waters ACQUITY TQD LC-MS/MS coupled with an electrospray ionization (ESI) source in the positive and negative modes. The flow rate and injection volume were 0.3 mL/min and $2.0{\mu}L$, respectively. The correlation coefficient of all analytes in the test ranges was greater than 0.98. The limits of detection and quantification values of the 25 marker compounds were in the ranges 0.03-19.43 and 0.09-58.29 ng/mL, respectively. As a result, methyl gallate, 3,4-dihydroxybenzaldehyde, evodiamine, and rutecarpine were not detected in this sample and the concentrations of the 21 compounds except for the above 4 compounds were $33.09-3,496.32{\mu}g/g$ in Onkyung-tang decoction. Among these compounds, paeonol was detected at the highest amount as a $3,496.32{\mu}g/g$.