Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “SALICYLIC ACID”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 541 records · Page 30Linked to original sources
PubMed1983

Molecular interaction between riboflavin and salicylic acid derivatives in nonpolar solvents.

The interaction of riboflavin-2',3',4',5'-tetrabutyrate (I) with salicylic acid (II), aspirin (acetylsalicylic acid, III), and salicylamide (IV) has been spectroscopically investigated to determine the binding mechanism. NMR and absorption spectra were measured in nonpolar solvents. The association constant K of the formation of complex was calculated from the absorption spectra. Compounds I and II form a 1:1 cyclic hydrogen-bonded dimer through the N-3 proton and the C-2 carbonyl oxygen of the isoalloxazine ring, and the carboxylic hydroxyl proton and carbonyl oxygen of II. Compounds I and III form a 1:1 cyclic hydrogen-bonded dimer by the same mode. Compound IV forms a 1:1 cyclic hydrogen-bonded dimer with I through the N-3 proton and the C-2 carbonyl oxygen of the isoalloxazine ring, and the amino proton and the carbonyl oxygen of IV. Salicylates produce marked changes in the absorption spectra of I. These spectral changes are attributed to the formation of the hydrogen-bonded dimer. It appeared that the strongest complex was formed with salicylic acid, a weaker one with aspirin, and an even weaker one with salicylamide.

Chemical Phenomena↗
PubMed1984

Topical treatment of distal ulcerative colitis with 4-amino-salicylic acid enemas.

Enemas of 4-amino-salicylic acid (4-ASA) have been compared with placebo enemas in a double-blind study for the treatment of distal ulcerative colitis of mild to moderate severity. 30 patients were randomised to receive enemas containing 1 g of 4-ASA or placebo, and 22 to receive 2-gram enemas of 4-ASA or placebo. For each dose of 4-ASA there was clinical and sigmoidoscopic improvement, which reached significance when all patients receiving 4-ASA enemas were compared with those receiving placebo enemas (Cochran's test: p less than 0.005). There was also a trend towards histological improvement, but this failed to reach the level of significance. These findings suggest that 4-ASA may provide a stable, inexpensive alternative to 5-ASA for the topical treatment of ulcerative colitis or for linking to carrier molecules for release in the colon.

Aminosalicylic Acid↗
PubMed2003

Photo- and antioxidative protection, and a role for salicylic acid during drought and recovery in field-grown Phillyrea angustifolia plants.

Mechanisms of photo- and antioxidative protection, the extent of oxidative stress, and salicylic acid accumulation in leaves of Phillyrea angustifolia L. (Oleaceae) plants exposed to drought and recovery in Mediterranean field conditions were studied. The amounts of alpha-tocopherol increased up to 4-fold and those of zeaxanthin increased up to 3-fold at relative leaf water contents (RWCs) of ca. 60%, which caused up to 70% increases in the de-epoxidation state of the xanthophyll cycle (DPS). While alpha-tocopherol increased further in severe drought, zeaxanthin levels and DPS remained constant, beta-carotene decreased and malondialdehyde (MDA) levels increased at RWCs below 50%. Though this was associated with significant decreases in the maximum efficiency of photosystem II photochemistry (F(v)/ F(m)), the same leaves that suffered from drought recovered after rainfalls, and similar MDA levels and F(v)/ F(m) ratios to those observed before drought were attained. During recovery (i) the F(v)/ F(m) ratio and beta-carotene levels increased slowly, (ii) alpha-tocopherol levels decreased sharply, to increase again, and (iii) MDA levels in leaves increased to values 35% higher than those observed at maximum drought, and decreased later. Salicylic acid (SA) levels showed a strong negative correlation (r(2)=0.857) with the RWC, and increased progressively up to 5-fold, during drought. During recovery, SA levels decreased, but remained slightly higher than those observed before drought. SA levels were positively correlated with those of alpha-tocopherol during drought (r(2)=0.718), but not during recovery (r(2)=0.221). We conclude that (i) P. angustifolia plants activate several mechanisms of photo- and antioxidative protection to withstand drought stress during a Mediterranean summer, (ii) endogenous SA levels increase in leaves of drought-stressed plants, thus suggesting a role for SA in plant responses to drought, and (iii) plants suffer oxidative stress during recovery, and this stress is more severe as the previous drought is more intense.

Disasters↗
PubMed1978

Simple and rapid high-pressure liquid chromatographic simultaneous determination of aspirin, salicylic acid, and salicyluric acid in plasma.

A rapid and sensitive high-pressure liquid chromatographic assay was developed for aspirin, salicylic acid, and salicyluric acid in plasma. The procedure involves the solvent extraction of these compounds from plasma and separation using a reversed-phase column eluted by acidified aqueous acetonitrile. Small quantitites of aspirin can be assayed directly in the presence of a large quantity of salicylic acid. The assay is also free from blank interference.

Aspirin↗
PubMed2004

Ultrastructural changes and location of beta-1, 3-glucanase in resistant and susceptible cotton callus cells in response to treatment with toxin of Verticillium dahliae and salicylic acid.

Calli from two cotton cultivars susceptible and resistant to Verticillium wilt, were treated with a crude toxin of Verticillium dahliae (VD-toxin) plus salicylic acid (SA). Cells treated with VD-toxin showed distinct ultrastructural changes. Cells from the susceptible cultivar displayed damage to plasma membrane and cytoplasm. The deleterious effect on cells of the resistant cultivar, with an accumulation of electron-dense precipitate in the vacuoles, was less noticeable. Exogenous SA protected callus cells from VD-toxin. We also report the localization of beta-1,3-glucanase in callus cells with immunofluorescence Labeling. Stronger fluorescence was observed in the extracellular space in resistant than in susceptible cotton; strongest in resistant cotton after 5 days of treatment with VD-toxin plus SA. The findings reported here indicate an important role of exogenous salicylic acid in the induction of resistance to VD-toxin in cotton. Coupled with an increase in beta-1,3-glucanase, cellular integrity is maintained and damage to cell wall and plasma membrane is avoided.

Cellulases↗
PubMed1991

Voltammetric behaviour of salicylic acid at a glassy carbon electrode and its determination in serum using liquid chromatography with amperometric detection.

Cyclic voltammetry was used to investigate the oxidation of salicylic acid at a planar glassy carbon electrode. The electrode reaction was found to be dependent on the pH and ionic strength of the acetate buffer, which contained 35% methanol. Under these conditions the maximum electrochemical signal was obtained with a supporting electrolyte of 0.06 mol dm-3 acetate buffer in 35% methanol (pH 5.0). The peak current value (ip) increased by approximately 10% when the methanol concentration was decreased to 8%. The substance was found to undergo an irreversible reaction involving one electron and possibly two protons in the initial oxidation step with at least one possible quasi-reversible follow-up reaction. The optimum mobile phase for the liquid chromatography, with amperometric detection, of the serum extracts was found to be 0.06 mol dm-3 acetate buffer in 8% methanol (pH 5.0); the acidified serum was extracted with a mixture of chloroform and acetonitrile (60 + 40), prior to injection onto a reversed-phase column. The peak current was measured at +1.35 V and the calibration graph was found to be linear in the range 4-200 ng of sample injected. The average recovery from serum was found to be 60% with a relative standard deviation of 5.8%. A pharmacokinetic study was carried out and the results obtained were comparable to those found in the literature. It was concluded that the method developed had possible application for the measurement of trace levels of salicylic acid in clinical studies.

Chromatography, High Pressure Liquid↗
PubMed1978

Effect of salicylic acid on articular cartilage in organ culture.

An organ culture system was used to study the metabolic effects of exposure of articular cartilage to increasing concentrations of salicylic acid. It was shown that concentration of salicylate above 1 mM inhibited the incorporation of 35S-sulphate into proteoglycans and at concentrations above 2.5 mM inhibited the incorporation of 3H-proline into collagen. Long-term exposure of the cartilage to salicylic acid at concentrations above 1 mM had a toxic effect on both proteoglycan and collagen synthesis.

Animals↗
PubMed1987

The effect of acetyl salicylic acid and indomethacin on cell proliferation kinetics in the human gastric mucosa.

To determine the effect of acetyl salicylic acid and Indomethacin on the rate of cell proliferation in the human gastric stomach, 6 healthy volunteers received daily 3 g of acetyl salicylic acid or 150 mg of indomethacin for one week in a double-blind crossover trial. Cell proliferation was assessed by means of tritiated thymidine and autoradiography. The labelling index did not change, indicating that cell proliferation to compensate for the exfoliation caused by ASA and indomethacin does not increase.

Adult↗
PubMed1982

p-Amino salicylic acid - oxidized cellulose system: a model for long term drug delivery.

The mobilization of p-amino salicylic acid (PASA) on periodic oxidized cellulose (O.C) as a biocompatible carrier was investigated. The immobilization of the PASA is based on Schiff's base formation between the amino group of PASA and the aldehyde group of O.C. The in vivo and in vitro release of p-amino salicylic acid was studied. Such a system may be useful for the sustained delivery of the drugs in the body, since O.C. itself is a biosoluble carrier.

Aminosalicylic Acid↗
PubMed1996

Competence for Elicitation of H2O2 in Hypocotyls of Cucumber Is Induced by Breaching the Cuticle and Is Enhanced by Salicylic Acid.

To study H2O2 production, the epidermal surfaces of hypocotyl segments from etiolated seedlings of cucumber (Cucumis sativus L.) were gently abraded. Freshly abraded segments were not constitutively competent for rapid H2O2 elicitation. This capacity developed subsequent to abrasion in a time-dependent process that was greatly enhanced in segments exhibiting an acquired resistance to penetration of their epidermal cell walls by Colletotrichum lagenarium, because of root pretreatment of the respective seedlings with 2,6-dichloroisonicotinic acid. When this compound or salicylic acid was applied to abraded segments, it also greatly enhanced the induction of competence for H2O2 elicitation. This process was fully inhibited by 5 [mu]M cycloheximide or 200 [mu]M puromycin, suggesting a requirement for translational protein synthesis. Both a crude elicitor preparation and a partially purified oligoglucan mixture from Phytophthora sojae also induced, in addition to H2O2 production, a refractory state, which explains the transient nature of H2O2 elicitation. Taken together, these results suggest that the cucumber hypocotyl epidermis becomes conditioned for competence to produce H2O2 in response to elicitors by a stimulus resulting from breaching the cuticle and/or cutting segments. This conditioning process is associated with protein synthesis and is greatly enhanced when substances able to induce systemic acquired resistance are present in the tissue.

Journal Article↗
PubMed2002

Role of salicylic acid and NIM1/NPR1 in race-specific resistance in arabidopsis.

Salicylic acid (SA) and the NIM1/NPR1 protein have both been demonstrated to be required for systemic acquired resistance (SAR) and implicated in expression of race-specific resistance. In this work, we analyzed the role that each of these molecules play in the resistance response triggered by members of two subclasses of resistance (R) genes, members of which recognize unrelated pathogens. We tested the ability of TIR and coiled-coil-class (also known as leucine-zipper-class) R genes to confer resistance to Pseudomonas syringae pv. tomato or Peronospora parasitica in SA-depleted (NahG) and nim1/npr1 plants. We found that all of the P. syringae pv. tomato-specific R genes tested were dependent upon SA accumulation, while none showed strong dependence upon NIM1/NPR1 activity. A similar SA dependence was observed for the P. parasitica TIR and CC-class R genes RPP5 and RPP8, respectively. However, the P. parasitica-specific R genes differed in their requirement for NIM1/NPR1, with just RPP5 depending upon NIM1/NPR1 activity for effectiveness. These data are consistent with the hypothesis that at least in Arabidopsis, SA accumulation is necessary for the majority of R-gene-triggered resistance, while the role of NIM1/NPR in race-specific resistance is limited to resistance to P. parasitica mediated by TIR-class R genes.

Arabidopsis↗
PubMed2006

Simultaneous quantitative LC-ESI-MS/MS analyses of salicylic acid and jasmonic acid in crude extracts of Cucumis sativus under biotic stress.

Salicylic acid (SA) and jasmonic acid (JA) are plant hormones involved in basal resistance against plant pathogens and also in induced resistance. The aim of this study is to develop a fast and sensitive method to determine simultaneously the levels of both these hormones. The present paper proposes a method that includes hormone extraction with MeOH-H(2)O-HOAc (90:9:1, v/v), evaporation of the extracts, and injection into the liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) system in multiple reaction monitoring (MRM). Endogenous SA and JA levels in noninfested control cucumber cotyledons were 30.96 and 0.73ngg(-1) fresh weight, respectively. In roots, the levels were 8.31 and 15.82ngg(-1) FW, respectively. In plants treated with the biological control agent Trichoderma asperellum strain T-34, the levels of SA and JA did not differ from control plants. Rhizoctonia solani-diseased cucumber plants showed higher levels of SA and JA compared to noninfested controls (up to 2 and 13-fold higher, respectively). Detection limits for SA and JA were 0.45 and 0.47ngg(-1) fresh weight, respectively. The results of our research include the development of a method that is both fast and highly sensitive in the simultaneous quantitation of SA and JA from crude cucumber plant extracts, avoiding any purification and derivatization steps.

Chromatography, Liquid↗
PubMed1996

Race-Specific Elicitors of Cladosporium fulvum Induce Changes in Cell Morphology and the Synthesis of Ethylene and Salicylic Acid in Tomato Plants Carrying the Corresponding Cf Disease Resistance Gene.

Defense responses mediated by the genetically unlinked Cf-9 and Cf-2 genes were compared with those involving no Cf gene (Cf0). Compatible tomato (Lycopersicon esculentum)-Cladosporium fulvum intercellular washing fluids were injected into tomato cotyledons, and the kinetics of responses was monitored under conditions of 70 and 98% relative humidity. The latter conditions suppressed the normal macroscopic responses. For the Cf-9-Avr9 interaction, stomatal opening was induced within 3 to 4 h and after 9 h mesophyll cell death commenced. A burst of ethylene production occurred between 9 and 12.5 h and remained elevated. Free salicylic acid levels increased after 12 h, peaked at 24 h, and thereafter declined. For the Cf-2-Avr2 interaction, stomata became plugged after 8 h, and salicylic acid and ethylene levels increased by 12 and 18 h, respectively, and thereafter declined. Host cell death commenced around vascular tissue by 24 h. Cell death in both incompatible interactions was frequently preceded by cell enlargement. For Cf0-injected plants, no significant responses were detected. High humidity delayed and reduced the Cf-Avr-gene-dependent cell death and ethylene synthesis, whereas induced salicylic acid levels were unaffected for Cf-2-Avr2 and reduced in magnitude only for Cf-9-Avr9.

Journal Article↗
PubMed2000

Tobacco transcription factor TGA2.2 is the main component of as-1-binding factor ASF-1 and is involved in salicylic acid- and auxin-inducible expression of as-1-containing target promoters.

In higher plants, activating sequence-1 (as-1) of the cauliflower mosaic virus 35 S promoter mediates both salicylic acid (SA)- and auxin-inducible transcriptional activation. Originally found in promoters of several viral and bacterial plant pathogens, as-1-like elements are also functional elements of plant promoters activated in the course of a defense response upon pathogen attack. Nuclear as-1-binding factor (ASF-1) and cellular salicylic acid response protein (SARP) bind specifically to as-1. Four different tobacco bZIP transcription factors (TGA1a, PG13, TGA2.1, and TGA2.2) are potential components of either ASF-1 or SARP. Here we show that ASF-1 and SARP are very similar in their composition. TGA2.2 is a major component of either complex, as shown by supershift analysis and Western blot analysis of DNA affinity-purified SARP. Minor amounts of a protein immunologically related to TGA2.1 were detected, whereas TGA1a was not detectable. Overexpression of either TGA2.2 or a dominant negative TGA2.2 mutant affected both SA and auxin (2, 4D) inducibility of various target promoters encoding as-1-like elements, albeit to different extents. This indicates that TGA2.2 is a component of the enhancosome assembling on these target promoters, both under elevated SA and 2,4D concentrations. However, the effect of altered TGA2.2 levels on gene expression was more pronounced upon SA treatment than upon 2,4D treatment.

Alleles↗
PubMed1989

Fate and effects of salicylic acid compounds in freshwater systems.

The comparative fates and effects of salicylic acid (SA) and Na salicylate in algae (Scenedesmus subspicatus, Monoraphidium minutum), in Lemna minor, and in Daphnia magna were examined. Test methods were principally based on the OECD testing guidelines with modifications in the procedures. The influence of fulvic acid (FA) on bioconcentration and on toxic effects was studied. FA addition significantly reduced the bioavailability of SA in L. minor and the algae species. SA was more toxic to Lemnaceae, algae, and daphnids than to its Na salt. Bioconcentration factors in S. subspicatus, M. minutum, and L. minor were about 10(3) in 72-96 hr. The reproducibility of D. magna was reduced by 38% at a concentration of 20 mg SA/liter.

Eukaryota↗
PubMed2006

Isolation of a novel ABC-transporter gene from soybean induced by salicylic acid.

This paper reports on the identification and characterization of a new ATP-binding cassette (ABC) transporter which was identified as a salicylic acid-induced gene from soybean (Glycine max cv. Williams 82) in a subtractive suppression hybridization approach. A fragment of an ABC-transporter gene was used to isolate a full-length cDNA clone for this gene with a length of 4750 bp. The encoded protein has a length of 1447 amino acids and is composed of two similar repeat units typical of full-size ABC transporters. The sequence displays a close relationship to plant pleiotropic drug resistance (PDR)-type transporters and, on a homology basis, clusters together with the Arabidopsis thaliana PDR12 gene, suggesting GmPDR12 as a name for the gene isolated from soybean. GmPDR12 is rapidly responsive to salicylic acid and methyl jasmonate. The mRNA starts to accumulate 30 min after the addition of the signalling compounds. Salicylic acid is required for the execution of the hypersensitive reaction in soybean cell suspension cultures inoculated with Pseudomonas syringae pv. glycinea. It has been demonstrated previously that salicylic acid can be substituted by a variety of functional analogues of salicylic acid. All of these compounds lead to a strong and rapid transcriptional activation of GmPDR12, suggesting a shared signalling pathway.

ATP-Binding Cassette Transporters↗
PubMed1988

Comparative absorption kinetics of imidazole and salicylic acid in volunteers after administration of ITF 182 tablets and suppositories.

Comparative absorption kinetics in volunteers of a new antiinflammatory drug (Selezen), in the form of 750 mg tablets and suppositories, were studied. The two components of the drug, imidazole and salicylic acid were found in plasma. Pharmacokinetic parameters were calculated according to a first order absorption. Salicylic acid showed a maximum concentration 59.2 +/- 5 min and 75.4 +/- 7.6 min after the administration of the tablet and suppository respectively; and imidazole after 86.3 +/- 10.8 min and 75.2 +/- 5.4 min, respectively.

Adult↗