• Journal of Environmental Science International
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• v.4 no.4
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• pp.317-321
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• 1995

ABA and SA showed different effect on stomatal closing on same condition. The addition of 1 M salicylic acid to fully opened stomata resulted in a significant reductionn of 22 % in stomatal aperture. However, 1 mM ABA reduced 73 % of stomatal aperture. The light absorption spectra of the salicylic acid solution showed that SA was degraded within 1 hour. Therefore, SA solution was resupplied % the detached epidermis every 30 min. during incubation and it was found that even at 10 $\mu$M SA induced stomatal closing significantly. Its effect was also greatly pH dependent. The reduction of stomatal aperture caused by 1 mM SA was most effective at lower pH (pH 7.2, 5 %: pH 6.2, 40 %; pH 5.2, 78 %). Therefore, if SA was properly treated to the epidermal strips in the medium, the effects of SA on stomatal closing were similar with those of ABA.

• BMB Reports
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• v.31 no.1
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• pp.70-76
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• 1998

The final step in ethylene biosynthesis is catalyzed by the enzyme 1-aminocyclopropane-1-carboxylate (ACC) oxidase. ACC oxidase was extracted from mung bean hypocotyls and its biochemical characteristics were determined. In vitro ACC oxidase activity required ascorbate and $Fe^{2+}$, and was enhanced by sodium bicarbonate. Maximum specific activity (approximately 20 nl ethylene $h^{-1}$ mg $protein^{-1}$) was obtained in an assay medium containing 100 mM MOPS (pH 7.5), $25\;{\mu}M$ $FeSO_4$, 6 mM sodium ascorbate, 1 mM ACC, 5 mM sodium bicarbonate and 10% glycerol. The apparent $K_m$ for ACC was $80{\pm}3\;{\mu}M$. Pretreating mung bean hypocotyls with ethylene increased in vitro ACC oxidase activity twofold. ACC oxidase activity was strongly inhibited by metal ions such as $Co^{2+}$, $Cu^{2+}$, $Zn^{2+}$, and $Mn^{2+}$, and by salicylic acid. Inactivation of ACC oxidase by salicylic acid could be overcome by increasing the $Fe^{2+}$ concentration of the assay medium. The possible mode of inhibition of ACC oxidase activity by salicylic acid is discussed.

• Molecules and Cells
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• v.22 no.2
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• pp.233-238
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• 2006

Endogenous salicylic acid (SA) and its predominant conjugates, SA 2-O-${\beta}$-D-glucoside (SAG) and the glucose ester of SA (SGE), increase dramatically during plant defense responses. Here I report the isolation and characterization of an Arabidopsis thaliana UDP-glucose:SA glucosyltransferase1 (AtSGT1) gene using a tobacco SGT gene previously reported, whose product catalyzes the formation of both SAG and SGE. The recombinant AtSGT1 protein had significant activities with SA and benzoic acid, and synthesized SAG and SGE. Northern blot analysis showed that AtSGT1 was rapidly induced both by exogenous SA and infection with the bacterial pathogen Pseudomonas syringae, indicating that pathogen-inducible AtSGT1 expression is an early disease response and may be involved in the accumulation of glucosyl SA during pathogenesis.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.19 no.1
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• pp.77-84
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• 1993

Two acardic acids showing antimicrobial activity against Propionibacterium acnes ATCC 6919, were isolated from Galla Rhois. They were identified as 6-pentadec-8-enyl salicylic acid and 6-pentadecyl aslicylic acid on the base of spectroscopic evidence.

• Korean Journal of Weed Science
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• v.18 no.4
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• pp.348-355
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• 1998

This study was conducted to identify allelopathic compounds in rye and oat straw extracts by HPLC analysis. These extracts were analyzed with 12 standard chemicals including salicylic acid. 11 chemicals in rye extract except for naringin and in oat extract except for catechin were identified. Salicylic acid(8.34mg/g) in rye straw extracts and naringin(7.50mg/g) in oat straw extracts among these standard chemicals were identified as the largest amount substance. The germination of Chenopodium ablum seeds was significantly inhibited by these chemicals at $10^{-3}$ and $10^{-4}M$ concentrations as compared to control. Salicylic acid in rye and naringin in oat were considered as the major allelopathic substances although allelopathy may be caused by an interaction of many substances. Yet many unidentified chemical compounds are present in both extracts.

• Analytical Science and Technology
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• v.8 no.3
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• pp.305-311
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• 1995

The stability constant of the complex between salicylic acid($H_2A$) and Fe(III) ion has been determined using UV-Vis absorption spectrometry and pH titration method in O.1M $KNO_3$ aqueous solution at $20^{\circ}C$ and compared with reference value, $logK_f=16.48$. The $pK_{a1}$ and $pK_{a2}$ of $H_2A$ are $2.92{\pm}0.08$ and $12.90{\pm}0.13$, respectively and the $logK_f$ of 1:1 complex Fe(III)-$H_2A$ system is $11.88{\pm}0.12$ at $20^{\circ}C$.

• Journal of the Korean Chemical Society
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• v.46 no.2
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• pp.99-116
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• 2002

The thiazolylazo compounds and their Co(II), Ni(II) and Cu(II) complexes of barbituric acid, uracil, thiouracil, citrazinic acid, chromotropic acid, gallic acid, pyrogallol and salicylic acid were pre-pared and characterized by $^1H$ NMR , IR and the effect of pH on the electronic absorption spectra . The mode of ionization, the electronic transitions and the dissociation constants were discussed. The stoichiometries of the complexes were of 1:1, 2:1 and 3:2 (M:L). The copper complexes are of isotropic ESR spectra (except that of gallic acid which showed a complicated one) and are of magnetically diluted behaviour with orbital con-tribution. Detailed DTA data were obtained and discussed.

• Korean Journal of Plant Resources
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• v.11 no.2
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• pp.195-201
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• 1998

Some morphological character were surveyed and PR-proteinases were induced and characterized from Lilium formosanum Wallace endeimc to Cheju island . Its flower characters were similar to those of white trumpet lilies(Lilium longiflorum Thunb) although its flowering period was later than that of white trumpet lilies and it hadd a wide range of variation among individuals. Six PR-proteinases(II-2, III-1, III-2, IV-1, IV-2 and V) were induced from bulbs by 2.5mM salicylic acid and almost excreted into the intercellular spaces. These PR-proteinases were strongly activated by Ca 2+, , whereas they were strongly inhibited by Cu2+ Co2+ and Fe2+ . Three PR proteinases(II-2, IV-1 and IV-2) were strongly inhibited by 1, 10 -phenanthroline, indicating that these enzymes are metallo-proteinases. Three PR-proteinases(III-1, III-2 and V) had a high sensitivity to PMSF and required $\beta$-mercaptoethanol for their activities. These results indicate that these proteinases are cysteine proteinases.

• Mycobiology
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• v.30 no.2
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• pp.88-92
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• 2002

Rehmannia glutinosa is a perennial medicinal plant belonging to the family Scrophulariaceae with more than 300 species known in the world, especially in temperate regions. Its roots have been used widely in Korea for medicinal purposes. However, it is commonly infected by various pathogens during storage, causing great damage to the roots, and impedes the intensive farming of the crop. Therefore, an attempt has been made to isolate and screen a resistance gene against the pathogen Fusarium oxysporum using differential display. We treated salicylic acid(SA), and isolated a resistance gene that responds to SA. As a result, we found that SA was involved in plant defense mechanism in pathogenicity tests with SA treated and non-treted plants, and we isolated a partial PR-la gene through differential display polymerase chain reaction(DD-PCR) method.

• International Journal of Computer Science & Network Security
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• v.22 no.6
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• pp.91-96
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• 2022

The photocatalytic degradation of salicylic acid takes place in several stages involving coupled phenomena, such as the transport of molecules and the chemical reaction. The systems of transport equations and the photocatalytic reaction are numerically solved using COMSOL Mutiphysics (CM) simulation software. CM will make it possible to couple the phenomena of flow, the transport of pollutants (salicylic acid) by convection and diffusion, and the chemical reaction to the catalytic area (bauxite or TiO2 doped by nanoparticles). The simulation of the conversion rate allows to correctly fit the experimental results. The temporal simulation shows that the reaction reaches equilibrium after a transitional stage lasting over one minute. The outcomes of the study highlight the importance of diffusion in the boundary layer and the usefulness of injecting micro-agitation into the microchannel flow. Under such conditions, salicylic acid degrades completely.