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The role of triterpenoid on reactive oxygen scavenging system: approach from the new chemiluminescence system (XYZ system).

We propose that the reactive oxygen species/hydrogen donor/mediator system (XYZ system) is a new chemiluminescence system for the measurement of reactive oxygen scavenging activity. By using this method, we demonstrated the role of triterpenoid on a reactive oxygen scavenging system. DDMP (2,3-dihydro-2,5-dihydroxy-6-methyl-4H-pyran-4-one) conjugated saponin from soybean, produced a low level light emission in the presence of H202 (X) and gallic acid (Y). The soybean saponin acted as a mediator (Z) on the reactive oxygen scavenging system. When comparing the data of photon emission properties of saponin with that of cholic acids, it concludes that DDMP moiety of soybean saponin plays an important role rather than the aglycon moiety in the radical scavenging system.

Cotyledon↗

Identification and quantification of low molecular weight phenolic antioxidants in seeds of evening primrose (Oenothera biennis L.).

Crude extracts of evening primrose meal were prepared in 56% (v/v) acetone and separated into six fractions (I-VI) using a Sephadex LH-20 column. Qualitative tests for phenolic and vanillin positive compounds produced positive results for all fractions. Silica gel thin-layer chromatography of fractions III and V allowed the location and isolation of two spots containing moderate to strong antioxidative compounds. High-performance liquid chromatography of the spot isolated from fraction III showed the resolution of two structurally related compounds, whereas that of the spot from fraction V showed the presence of one compound. Nuclear magnetic resonance spectroscopy and electron impact mass spectrometry produced sufficient evidence to identify the isolated compounds as (+)-catechin, (-)-epicatechin, and gallic acid. These compounds accounted for about 10.5 and 1.7% of the dry mass of the crude extracts and meal, respectively.

Antioxidants↗

Characterization of five phyllosphere bacteria isolated from Rosa rugosa leaves, and their phenotypic and metabolic properties.

Five gram-negative bacteria, all of which were Enterobacteriaceae, were isolated from the phyllosphere of green or senescing leaves of Rosa rugosa, and their phenotypic and physiological characteristics were examined. Partial 16S rDNA sequences led to identification of these isolates as Pantoea agglomerans, Klebsiella terrigena, Erwinia rhapontici, and two strains of Rahnella aquatilis. Interestingly, these phyllosphere bacteria had certain phenotypic and physiological convergences, while they showed their own metabolic properties toward phenolic compounds of plant origin. In particular, the two Ra. aquatilis isolates from the green leaves had a substrate-inducible gallate decarboxylase activity in the resting cells that had been cultured in 1 mM gallic acid- or protocatechuic acid-containing medium. The other three isolates from the senescing leaves did not have this enzyme activity. Simple phenolics that the Ra. aquatilis decarboxylatively produced from benzoic acid derivatives had better antimicrobial activities than those of the substrates.

Antifungal Agents↗

[Studies on the chemical constituents in vine stem of Bauhinia championii (I)].

OBJECTIVE: To study the chemical constituents of Bauhinia championii. METHOD: Compounds were isolated from the ethanolic extract of B. championii by silica gel column Chromatography, and their structures were elucidated by spectral analyses. RESULT: Five compounds were isolated and elucidated as 2,4,6-trimethoxyphenol 1-O-beta-D-(6'-O-galloyl)-glucopyranoside (1), (+/-)-lyoniresinol (2), daucosterol (3), beta-sitosterol (4) and gallic acid (5). CONCLUSION: Compounds 1-4 were isolated from B. championii for the first time.

Anisoles↗

Cytotoxicity and antibacterial activity of Sida rhombifolia (Malvaceae) grown in Bangladesh.

The cytotoxicity and antibacterial activities of crude extracts from the leaves of Sida rhombifolia were investigated. The ethyl acetate extract showed potent cytotoxicity with LC50 values (5.41 ppm) comparable to the reference standard, gallic acid. All the extracts showed weak antibacterial activity against both Gram-positive and Gram-negative test organisms.

Animals↗

Accelerating action of tea on mouse skin carcinogenesis.

The effect of different tannin-containing aqueous solutions on the carcinogenic action of benzo(a)pyrene (BP) on the mouse skin was investigated. It was found that the appearance of tumours was accelerated in mice treated with either tea or an oak extract after a single application of BP. The time of appearance of tumours in mice treated with gallic acid or tannic acid after treatment with BP was similar to that in the group treated with BP alone. The overall incidence of tumours was similar in all five groups.

Animals↗

[Studies on chemical constituents in herb of Polygonum orientale].

OBJECTIVE: To study the chemical constituents of the essential substance from Polygonum oriental. METHOD: Compounds were isolated with silica gel and polyamide chromatography and their structures were determined by spectral analysis and chemical evidence. RESULT: Six compounds were obtained and identified as myricitrin, luteolin, gallic acid, catechin, protocatechuic acid, p-hydroxycinnamic acid. CONCLUSION: Six compounds were isolated from P. oriental for the first time.

Flavonoids↗

[Polyphenols from leaves of Euphorbia hirta L].

Six compounds have been isolated from the leaves of Euphorbia hirta and identified as gallic acid, quercitrin, myricitriu, 3,4-di-O-galloylquinic acid, 2,4,6-tri-O-galloyl-D-glucose and 1,2,3,4, 6-penta-O-galloyl-beta-D-glucose on the basis of physicochemical and spectroscopic methods.

Drugs, Chinese Herbal↗

The effects of caffeic acid and its related catechols on hydroxyl radical formation by 3-hydroxyanthranilic acid, ferric chloride, and hydrogen peroxide.

The effect of caffeic acid on hydroxyl radical formation through a reaction, which contained 0.22 M carbonate buffer (pH 7.4), 0.22 mM 3-hydroxyanthranilic acid, 87 mM 5,5-dimethyl-1-pyrroline-N-oxide (DMPO), 2.9 mM hydrogen peroxide, and 14 microM FeCl3, was investigated. The addition of 30 microM caffeic acid resulted in the decrease of hydroxyl radical formation in the reaction mixture. Chlorogenic acid, 3,4-dihydroxy-phenylalanine noradrenaline, gallic acid, dopamine, epicatechin, and D-(+)-catechin also suppressed the hydroxyl radical formation. In regard to the positional isomers of benzenediol, o-benzenediol inhibited the hydroxyl radical formation, but m and p-benzenediol did not. The inhibitory effect of the hydroxyl radical formation seems to be due to the chelation of iron ions by the catechols. Supporting evidence includes the diminished effect of catechols in the presence of EDTA (a potent iron ion chelator) and the observation of a visible band at 450 nm caused by the interaction between caffeic acid and iron ions. Additionally, the visible band (506 nm) was observed in the solution of o-benzenediol and ferric chloride but not in the solution of m- or p-benzenediol and ferric chloride. Thus compounds with adjacent hydroxyl groups on aromatic rings might inhibit hydroxyl radical formation.

3-Hydroxyanthranilic Acid↗

A new aurone and two rare metabolites from the leaves of Diospyros melanoxylon.

A new aurone, 4,6-dihydroxy-2-[alpha,alpha-(4-hydroxyphenyl)hydroxy]methylene-3(2H)-benzofuranone (2) and two rare metabolites viz. selin-4(15)-en-1beta,11-diol (5) and 5,7-dihydroxy-3-O-beta-D-glucopyranosyl-l''' --> 6''glucopyranoside-2-{4-hydroxyphenyl}-4H-benzopyran-4-one (6) in addition to the known protocatechuic acid methyl ester (1), quercitin (3) and gallic acid (4) were isolated from the methanol extract of Diospyros melanoxylon leaves. The structures were elucidated by a combination of chemical and spectroscopic analysis. Interestingly, compound 2 was found to exist in both E- and Z-isomeric forms in a 15:85 ratio. The present isolation of compounds 2 and 5 assumes taxonomic significance as aurones and sesquiterpenes have not yet been reported from the Diospyros genus, consisting of more than 350 identified species.

Benzofurans↗

Terminalia arjuna.

Terminalia arjuna is a deciduous tree found throughout India growing to a height of 60-90 feet. The thick, white-to-pinkish-gray bark has been used in India's native Ayurvedic medicine for over three centuries, primarily as a cardiac tonic. Clinical evaluation of this botanical medicine indicates it can be of benefit in the treatment of coronary artery disease, heart failure, and possibly hypercholesterolemia. It has also been found to be antibacterial and antimutagenic. Terminalia's active constituents include tannins, triterpenoid saponins (arjunic acid, arjunolic acid, arjungenin, arjunglycosides), flavonoids (arjunone, arjunolone, luteolin), gallic acid, ellagic acid, oligomeric proanthocyanidins (OPCs), phytosterols, calcium, magnesium, zinc, and copper.

Animals↗

[Studies on the chemical constituents in root of Rheum rhizastachyum].

OBJECTIVE: To investigate the chemical constituents from the root and rhizome of Rheum rhizastachyum. METHOD: The compounds were isolated by column chromatography on silica gel, Sephadex LH-20, MCI-gel CHP-20P separately and their structures were elucidated by chemical and spectral technology. RESULT: Six compounds were isolated and identified as chrysophanol, emodin, gallic acid, sucrose, 1-O-beta-D-glucopyranosyl-chrysophanols, 1-O-beta-D-glucopyranosyl-emodin. CONCLUSION: All the compounds were obtained from this plant for the first time.

Anthraquinones↗

[Studies of the chemical constituents of Ardisia pusilla A. DC].

Six chemical compounds isolated from the leaves and stems of Ardisia pusilla were identified as gallic acid (I), succinic acid (II), naringenin-6-C-glucoside (III), kaempferol-3-O-beta-D-galactoside (IV) by chemical and spectroscopic analysis. They were isolated from Ardisia plant for the first time.

Drugs, Chinese Herbal↗

Anti-babesial and anti-plasmodial compounds from Phyllanthus niruri.

Bioassay-guided fractionation of boiled aqueous extracts from the whole plant of Phyllanthus niruri led to the isolation of 1-O-galloyl-6-O-luteoyl-alpha-d-glucose (1), with IC(50) values of 4.7 microg/mL against Babesia gibsoni and 1.4 microg/mL against Plasmodium falciparum in vitro. The known compounds beta-glucogallin (2), quercetin 3-O-beta-d-glucopyranosyl-(2-->1)-O-beta-d-xylopyranoside (3), beta-sitosterol, and gallic acid were also isolated. Structures of these compounds were elucidated on the basis of their chemical and spectroscopic data.

Animals↗

A new stilbene glycoside from Elephantorrhiza goetzei.

A new stilbene glycoside, 5-methoxy-(E)-resveratrol 3-O-rutinoside (1) was isolated from the root bark of Elephantorrhiza goetzei, along with known compounds, namely gallic acid, (E)-resveratrol, (+/-)-catechin, (+/-)-gallocatechin and oleanene triterpenoids. The combined ethyl acetate-methanol extract exhibited high lethality against brine shrimp larvae (LC(50) 10.8 ppm) compared to the isolates, some of which were not active.

Animals↗

[Studies on the chemical constituents of hypogeal part from Limonium bicolor].

OBJECTIVE: To study chemical constituents of hypogeal part from Limonium bicolor. METHODS: Column chromatography and spectral analysis were usded to isolate and identify the constituents, respectively. RESULTS: Four compounds were isolated and identified as beta-sitosterol (1), gallic acid (2), luteolin (3), quercetin (4). Some white grease was obtained, and nine constituents were identified by GC-MS elementarily. They were 2,4-dimethyl-heptene (5), ethylbenzene (6), O-xylene (7), styrene (8), hexadecanoic acid etylester (9), 9,12-octodecadienoic acid etylester (10), diisooctyl phthalate (11), alpha-amyrin (12), beta-amyrin (13), respectively. CONCLUSION: Compound 1 is isolated from Limonium bicolor and compounds 5-13 are extracted from Limonium Mill for the first time.

Benzene Derivatives↗

Theaflavin-3,3'-digallate from black tea blocks the nitric oxide synthase by down-regulating the activation of NF-kappaB in macrophages.

Nitric oxide (NO) plays an important role in inflammation and also in multiple stages of carcinogenesis. We investigated the effects of various tea polyphenols, including theaflavin, a mixture of theaflavin-3-gallate and theaflavin-3'-gallate, theaflavin-3,3'-digallate, thearubigin, and (-)-epigallocatechin-3-gallate on the induction of NO synthase in lipopolysaccharide-activated murine macrophages, RAW 264.7 cells. Theaflavin-3,3'-digallate was found to be stronger than (-)-epigallocatechin-3-gallate in inhibiting NO generation and inducible NO synthase protein in activated macrophages, while theaflavin, a mixture of theaflavin-3-gallate and theaflavin-3'-gallate and thearubigin were less effective. Inhibition of NO production was observed when cells were cotreated with theaflavin-3,3'-digallate and lipopolysaccharide. Western blot and reverse transcriptase-polymerase chain reaction (RT-PCR) analyses demonstrated that significantly reduced 130-kDa protein and mRNA levels of inducible NO synthase were expressed in lipopolysacchride-activated macrophages with theaflavin-3,3'-digallate, compared to those without theaflavin-3,3'-digallate. Electrophoretic mobility shift assay (EMSA) indicated that theaflavin-3,3'-digallate blocked the activation of nuclear factor kappaB (NF-kappaB), a transcription factor necessary for inducible NO synthase induction. Theaflavin-3,3'-digallate also blocked phosphorylation of IkappaB from cytosolic fraction and reduced lipopolysacchride-induced nuclear accumulation of transcription factor NF-kappaB p65 and p50 subunits. These results suggest that theaflavin-3,3'-digallate decreases the protein levels of inducible NO synthase by reducing the expression of inducible NO synthase mRNA, and the reduction could be via preventing the activation of NF-kappaB, thereby inhibiting the induction of inducible NO synthase transcription. It was also demonstrated that the gallic acid moiety of theaflavin-3,3'-digallate is essential for their potent anti-inflammation activity.

Animals↗

Free radical scavenging properties of wheat extracts.

Three hard winter wheat varieties (Akron, Trego, and Platte) were examined and compared for their free radical scavenging properties and total phenolic contents (TPC). Free radical scavenging properties of wheat grain extracts were evaluated by spectrophotometric and electron spin resonance (ESR) spectrometry methods against stable 2,2-diphenyl-1-picryhydrazyl radical (DPPH*) and radical cation ABTS*+ (2,2'-azino-di[3-ethylbenzthiazoline sulfonate]). The results showed that the three wheat extracts differed in their capacities to quench or inhibit DPPH* and ABTS*+. Akron showed the greatest activity to quench DPPH radicals, while Platte had the highest capacity against ABTS*+. The ED50 values of wheat extracts against DPPH radicals were 0.60 mg/mL for Akron, 7.1 mg/mL for Trego, and 0.95 mg/mL for Platte under the experimental conditions. The trolox equivalents against ABTS*+ were 1.31 +/- 0.44, 1.08 +/- 0.05, and 1.91 +/- 0.06 micromol/g of grain for Akron, Trego, and Platte wheat, respectively. ESR results confirmed that wheat extracts directly reacted with and quenched free radicals. The TPC were 487.9 +/- 927.8 microg gallic acid equivalents/g of grain. No correlation was observed between TPC and radical scavenging capacities for DPPH* and ABTS*+ (p = 0.15 and p > 0.5, respectively).

Benzothiazoles↗