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HPC Fingerprints and In vitro Antimicrobial Activity of Syringic Acid, Caffeic Acid and 4-hydroxybenzoic Acid against Ganoderma boninense  [PDF]
K.P. Chong,S. Rossall,M. Atong
Journal of Applied Sciences , 2011,
Abstract: This study discusses the in vitro antimicrobial activity and fungitoxicity of syringic acid, caffeic acid and 4-hydroxybenzoic acid which is found in oil palm root. The presence of these phenolics were first confirmed with the injection of standards using HPLC in a gradient system developed with methanol and 0.1% phosphoric acid. Experiments were observed for fourteen days, repeated at least three times and data were recorded daily. The antimicrobial activities and fungitoxicity of the phenolics against Ganoderma boninense were expressed in inhibition of radial growth of G. boninense on PDA ameliorated with the three different phenolics with a range concentration of 0.5-2.5 mg mL-1. Syringic acid was found to be very fungitoxic to G. boninense even at concentration of 0.5 mg mL-1, the lowest concentration tested in this experiment. When the concentration is increase to 1.0 mg mL-1 of syringic acid, the pathogen is inhibited. Caffeic acid and 4-hydroxybenzoic acid were having inhibitory effect with the highest concentration tested; 2.5 mg mL-1 strongly inhibited the growth of G. boninense in comparison to the control.
Degradation of 2-hydroxybenzoic acid by advanced oxidation processes
Zanta, C. L. P. S.;Martínez-Huitle, C. A.;
Brazilian Journal of Chemical Engineering , 2009, DOI: 10.1590/S0104-66322009000300006
Abstract: in this study, advanced oxidation processes (aops) such as the uv/h2o2 and fenton processes were investigated for the degradation of 2-hydroxybenzoic acid (2-hba) in lab-scale experiments. different [h2o2]/[2-hba] molar ratios and ph values were used in order to establish the most favorable experimental conditions for the fenton process. for comparison purposes, degradation of 2-hba was carried out by the uv/h2o2 process under fenton experimental conditions. the study showed that the fenton process (a mixture of hydrogen peroxide and fe2+ ion) was the most effective under acidic conditions, leading to the highest rate of 2-hydroxybenzoic acid degradation in a very short time interval. this same process led to a six-fold acceleration of the oxidation rate compared with the uv/h2o2 process. the degradation of 2-hydroxybenzoic acid was found to follow first-order kinetics and to be influenced by the type of process and the experimental conditions. the experimental results showed that the most favorable conditions for 2-hba degradation by the fenton process are ph around 4-5, [fe2+] = 0.6 mmol.l-1, and [h2o2]/[2-hba] molar ratio = 7. the hydroxylation route is explained here for the two processes, and the results are discussed in the light of literature information.
Effect of isomers of hydroxybenzoic acid on the growth and metabolism of Chlorella vulgaris Beijerinck (Chlorophyceae)
Andrzej Bajguz,Romuald Czerpak,Alicja Piotrowska,Magdalena Polecka
Acta Societatis Botanicorum Poloniae , 2001, DOI: 10.5586/asbp.2001.032
Abstract: The isomers o-, m-, and p- of hydroxybenzoic acid (HBA) in the concentration range 10-1-10-4 M in the unicellular green alga Chlorella vulgaris (Chlorophyceae) display marked biological activity. The o-HBA isomer, commonly known as salicylic acid, in a concentration of 10-4 M exerted the most stimulating effect on the parameters analysed (the number of cells, dry mass, the content of chlorophylls a and h, carotenoids, soluble proteins and their secretion, monosaccharides, DNA and RNA) whereas p-HBA had weak stimulating properties. On the other hand, m-HBA had a weak inhibitory effect on the growth of C. vulgaris and all the biochemical parameters analysed in comparison with the control culture of algae devoid of HBA isomers.
The Influence of Ferulic Acid and p-Hydroxybenzoic Acid on Nitrogen Mineralization in Soil

Wei Wang,Xinru Zhu,E Wu,Ruixia Ma,Xiufen Liu,

环境科学 , 2000,
Abstract: An ivestigation on the influence of the ferulic acid and p hydroxybenzoic acid on the nitrogen mineralization in the soil was carried out.It was showed that ferulic acid and p hydroxybenzoic acid could immobilize the nitrogen in the soil and the influence of the p hydroxybenzoic acid was stronger than that of ferulic acid.The results also showed that the soil nitrogen mineralization was much stronger influenced by straws than that of phenolic acids,and with different trends.
Syringic Acid Extracted from Herba dendrobii Prevents Diabetic Cataract Pathogenesis by Inhibiting Aldose Reductase Activity  [PDF]
Xiaoyong Wei,Dan Chen,Yanchun Yi,Hui Qi,Xinxin Gao,Hua Fang,Qiong Gu,Ling Wang,Lianquan Gu
Evidence-Based Complementary and Alternative Medicine , 2012, DOI: 10.1155/2012/426537
Abstract: Objective. Effects of Syringic acid (SA) extracted from dendrobii on diabetic cataract (DC) pathogenesis were explored. Methods. Both in vitro and in vivo DC lens models were established using D-gal, and proliferation of HLEC exposed to SA was determined by MMT assay. After 60-day treatment with SA, rat lens transparency was observed by anatomical microscopy using a slit lamp. SA protein targets were extracted and isolated using 2-DE and MALDI TOF/TOF. AR gene expression was investigated using qRT-PCR. Interaction sites and binding characteristics were determined by molecule-docking techniques and dynamic models. Results. Targeting AR, SA provided protection from D-gal-induced damage by consistently maintaining lens transparency and delaying lens turbidity development. Inhibition of AR gene expression by SA was confirmed by qRT-PCR. IC50 of SA for inhibition of AR activity was 213.17?μg/mL. AR-SA binding sites were Trp111, His110, Tyr48, Trp20, Trp79, Leu300, and Phe122. The main binding modes involved hydrophobic interactions and hydrogen bonding. The stoichiometric ratio of non-covalent bonding between SA and AR was 1.0 to 13.3. Conclusion. SA acts to prevent DC in rat lenses by inhibiting AR activity and gene expression, which has potential to be developed into a novel drug for therapeutic management of DC. 1. Introduction Increasing population senescence due to improved living standards and diet has increased the incidence rate of diabetic cataract, a frequent cause of vision impairment and blindness [1]. A complex pathogenic mechanism underlies diabetic cataract. Though the exact mechanism remains uncertain, a large body of research indicates that aldose reductase (AR) is a key enzyme involved in DC development [2]. In order to reduce diabetic cataract incidence and slow the progression of diabetic cataract in current patients, further understanding of the mechanistic involvement of AR in diabetic cataract development and progression is required. In diabetic patients, AR activation increases polyalcohol metabolism rates. As a result, glucitol accumulation in the eye caused increased osmotic pressure, alterations to cell membrane permeability, edema, and damage to cells of the optical lens. These changes block the passage of nutrients into the lens, further resulting in reduced amino acid levels accompanied by protein denaturation and polymerization. The end result of this process is cataract formation and progression [3]. Previous studies of the experimental aldose reductase inhibitors GP-1447 and KIOM-79 have demonstrated a relationship between AR
Research on the Separation of Three Isomers of Hydroxybenzoic Acid by Capillary Zone Electrophoresis

ZHANG Qiang,

色谱 , 2001,
Abstract: The separation behavior of o hydroxybenzoic acid, m hydroxybenzoic acid and p hydroxybenzoic acid in high performance capillary zone electrophoresis was investigated using cetyltrimethylammonium bromide(CTAB) as reversed reagent for electroosmotic flow The effects of pH of buffer solution and volume fraction of methanol on the separation, peak shape and elution order were studied
Synthesis of Bosutinib from 3-Methoxy-4-hydroxybenzoic Acid  [PDF]
Xiao Jia Yin,Guan Hong Xu,Xu Sun,Yan Peng,Xing Ji,Ke Jiang,Fei Li
Molecules , 2010, DOI: 10.3390/molecules15064261
Abstract: This paper reports a novel synthesis of bosutinib starting from 3-methoxy-4-hydroxybenzoic acid. The process starts with esterification of the starting material, followed by alkylation, nitration, reduction, cyclization, chlorination and two successive amination reactions. The intermediates and target molecule were characterized by 1H-NMR, 13C-NMR, MS and the purities of all the compounds were determined by HPLC.
2-Hydroxybenzoic acid–purin-6-amine (3/1)  [cached]
Lian-cai Du,Wu-lan Zeng,Xue-ying Liu,Fang-Fang Jian
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809025240
Abstract: In the title 3:1 adduct, 3C7H6O3·C5H5N5, an intramolecular O—H...O hydrogen bond occurs in each of the three 2-hydroxybenzoic acid molecules. In the crystal, the components are linked by N—H...O and O—H...N hydrogen bonds.
Synthesis of some bis- and mono-2-hydroxybenzoic acid derivatives and the determination of their acidity constants
Journal of the Serbian Chemical Society , 2000,
Abstract: Several bis- and mono-2-hydroxybenzoic acid derivatives were synthesized by the reaction of methyl 2-hydroxybenzoate with some alcohols (diols, polyols and amino alcohols) and their acidity constants were determined in 60 % aqueous ethanol by the potentiometric titration method. It has been shown that the biochemical behaviour of these compounds is greatly dependent on their acidity. It appears that the ester derivatives are weaker acids than the amide derivatives and, therefore, can be potentially more involved in the processes of metal ions transport in plants, whereas the introduction of OH and CH3 groups has a very small effect on the biochemical properties.
Induction of Heat Resistance in Wheat Coleoptiles by 4-Hydroxybenzoic Acid: Connection with the Generation of Reactive Oxygen Species  [PDF]
Yastreb T.O.,Kolupaev Yu.Ye.,Vayner A.O.
Journal of Stress Physiology & Biochemistry , 2012,
Abstract: The effect of 4-hydroxybenzoic acid (4-HBA) on resistance of coleoptiles of 4-day-old etiolated seedlings of wheat (Triticum aestivum L., cv. Elegiya) to damaging heating (10 min at 43°C) and possible dependence of this effect on changes in the activities of enzymes producing and scavenging reactive oxygen species (ROS) were investigated. Treatment of coleoptiles with 10 μM 4-HBA resulted in enhancing of superoxide anion-radical generation and maintaining of hydrogen peroxide content there in. Increasing of the rate of ROS production was significantly suppressed by inhibitors of NADPH oxidase (α-naphthol) and peroxidase (salicylhydroxamic acid). Under the influence of 4-HBA the activities of superoxide dismutase and apoplastic forms of peroxidase were increased. The activity of oxalate oxidase and catalase has not changed. Exogenous 4-HBA improved coleoptiles heat resistance and its effects were comparable with the influence of salicylic acid. Antioxidant agent BHT (butylhydroxytoluene), inhibitors of NADPH oxidase and peroxidase significantly reduced the increasing of wheat coleoptiles heat resistance, caused by 4-HBA action. It was concluded that 4-HBA influence on coleoptiles heat resistance is realized with the ROS mediation.
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