• Title/Summary/Keyword: benzoic acid

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Effect of Aromatic Ring Content on the Properties of Liquid Crystalline Copolyesters (방향족 고리 함량이 공중합 액정 폴리에스터의 성질에 미치는 영향)

  • Park, Jong-Ryul;Bang, Moon-Soo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.1
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    • pp.575-580
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    • 2014
  • The liquid crystalline copolymers were synthesized through direct polycondensation using 4-[4-(4-hydroxyphenoxy)butoxy]benzoic acid (HBBA) and p-hydroxy benzoic acid (HBA) as monomers. The structure and properties for synthesized copolymers were investigated by $^1H$-NMR, FT-IR, differential scanning calorimetry (DSC), thermogravimetry analysis (TGA) and polarizing optical microscope (POM). As result of investigations, inherent viscosities (${\eta}_{inh}$) of polymers were measured as 0.77~1.60 dL/g in phenol/p-chlorophenol/1,1,2,2-tetrachloroethane (25/40/35=w/w/w). Except for P-80, the ranges of the transition and mesophase temperature of copolymers were increased with increasing the amount of HBA. These properties of polymers were presumably due to increasing of the irregularity and rigidity of polymer chains.

Preparation of $\beta$-Cyclodextrinized Cellulosic Fiber and Deodouring Property ($\beta$-시클로덱스트린화 셀룰로오스 섬유의 제조 및 소취성)

  • Choi, Chang-Nam;Hwang, Tae-Yeon;Ko, Bong-Kook;Kim, Ryong;Hong, Sung-Hak;Kim, Sang-Yool
    • Polymer(Korea)
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    • v.25 no.5
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    • pp.635-641
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    • 2001
  • $\beta$-Cyclodextrine/benzoic acid complex was prepared and reacted with cyanuric chloride (2,4,6-trichloro-1,3,5-triazine). Identification of complex formation and reaction was checked by FT-IR, UV-Vis, and EDX. By reacting this material with cotton fiber, the deodourant fiber was prepared. The deodourizing property was evaluated by the concentration changes of aqueous ammonia solution after flowing ammonia gas through the column titled with deodourant fiber prepared. The deodourizing property was increased with an increase of concentration of $\beta$-cyclodextrine unit in the fiber. In the case of $\beta$-cyclodextrine/benzoic acid complex, the deodourzing property was much increased, comparing with the $\beta$-cyclodextrine only. It was considered to be the binding of aamonia gas caused by benzoic acid in the complex.

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Antimicrobial Effect of the Fractions Extracted from a Lotus (Nelumbo nucifera) Leaf (연잎 추출물의 항균 효과)

  • Lee, Kyung-Seok;Oh, Chang-Seok;Lee, Ki-Young
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.35 no.2
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    • pp.219-223
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    • 2006
  • In this study the antimicrobial activity of the extract from leaves of lotus (Nelumbo nucifera) was evaluated in comparison with benzoic acid. The $70\%$ ethanol extract was fractionated subsequently by hexane, chloroform, ethyl acetate, butanol and water, and the antimicrobial activity of each dried fraction was tested by paper disk diffusion method. The ethyl acetate fraction exhibited strong antimicrobial activity on the five strains of food born bacteria e.g. Bacillus subtilis, Staphylococcus aureus subsp. aureus, Escherichia coli, Salmonella Typhimurium and Pseudomonas nuorescens. The antimicrobial activity of the fraction was stronger than benzoic acid and showed no appreciable difference between on $Gm^+$ and $Gm^-$ bacteria. Heat treatment of the fraction at $110^{\circ}C$ for 1 hr did not change the degree of inhibitory effect. The ethyl acetate fraction showed almost perfect growth inhibition on the tested strains at over 800 ppm.

Effect of Self-Assembled Monolayer Treated ZnO on the Photovoltaic Properties of Inverted Polymer Solar Cells

  • Yoo, Seong Il;Do, Thu Trang;Ha, Ye Eun;Jo, Mi Young;Park, Juyun;Kang, Yong-Cheol;Kim, Joo Hyun
    • Bulletin of the Korean Chemical Society
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    • v.35 no.2
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    • pp.569-574
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    • 2014
  • Inverted bulk hetero-junction polymer solar cells (iPSC) composed of P3HT/PC61BM blends on the ZnO modified with benzoic acid derivatives-based self-assembled monolayers (SAM) are fabricated. Compared with the device using the pristine ZnO, the devices with ZnO surface modified SAMs derived from benzoic acid such as 4-(diphenylamino)benzoic acid (DPA-BA) and 4-(9H-carbazol-9-yl)benzoic acid (Cz-BA) as an electron transporting layer show improved the performances. It is mainly attributed to the favorable interface dipole at the interface between ZnO and the active layer, the eective passivation of the ZnO surface traps, decrease of the work function and facilitating transport of electron from PCBM to ITO electrode. The power conversion eciency (PCE) of iPSCs based on DPA-BA and Cz-BA treated ZnO reaches 2.78 and 2.88%, respectively, while the PCE of the device based on untreated ZnO is 2.49%. The open circuit voltage values ($V_{oc}$) of the devices with bare ZnO and SAM treated ZnO are not much different. Whereas, higher the fill factor (FF) and lower the series resistance ($R_s$) are obtained in the devices with SAMs modification.

Growth Characteristics and Ingredient Analysis According to the Transplanting Date and Distance of Dendranthema (L.). (감국 정식시기와 거리에 따른 생육특성과 성분 분석)

  • Jung, J.H.;Park, N.B.
    • Journal of Practical Agriculture & Fisheries Research
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    • v.22 no.1
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    • pp.65-77
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    • 2020
  • In order to industrialize of Dendranthema indicum (L.) DesMoul., which is a lot of commercially available and is synonymous with chrysanthemum tea, in the autumn of 2018, Dendranthema indicum (L.) DesMoul. seeds were collected from its own native region, and the seeds were germinated after refrigerated storage. Young seedlings were subjected to experiments in February, March, and April in the open field to examine the effects on the harvesting of leaves by distance and the growth of leaves and stems. The results of analyzing the components by collecting the leaves+stem after collecting the flower of Dendranthema indicum (L.) DesMoul. are as follows. 1. When D. indicum (L.) DesMoul. seedlings were planted according to the transplanting date, the number of flowers was 17.1 in the transplanting date in April. The diameter of the flower was 2.9cm, 16ea, 6.5~6.6g in the fresh weight, and the dry weight of the case was 1.1~1.2g. The leaves were 46~47ea in March and April in the planted area, 5.2~5.3cm in leaf length and 3.5~3.6cm in leaf width. 2. When planted D. indicum (L.) DesMoul. seedlings according to transplanting distance, the number of flowers was 16.2 when planted at 20×20cm intervals and, 16.8~17.1 at 30×30~50×50cm intervals. The diameter of the flower was 2.7~2.8cm, the number of petals was 8, the length of the petal was 0.8 cm, and fresh weight was 6.5~6.6g per flower. Leaves had the largest number of 47 of 30×30cm and 40×40cm, and leaf length appeared at the longest 6.2cm in the 50×50cm treatment area, but 5.2cm in the other treatment areas. 3. The extraction yield of D. indicum (L.) DesMoul. leaves+stems was 7.93%, and the extraction solvent colors were light green at 50, 60% and green at 70, 80, 90, 100%. The extraction yield of D. indicum (L.) DesMoul. flowers was 7.58%, the color of the extraction solvent was light yellow at 50, 60 and 70%, yellow at 80 and 90%, and dark yellow at 100%. 4. We confirmed 11 kinds of ingredients such as in D. indicum (L.) DesMoul. flowers are gallic acid, 4-hydroxy benzoic acid, methyl gallate, 4-hydroxy-3-methoxy benzoic, caffeic acid, salicylic acid, p-coumaric acid, sinapic acid, naringin, 4-melthoxyben, flavone. The content was 29.200-36.900ppm. 5. The components contained in the D. indicum (L.) DesMoul. leaf+stem, salicylic acid appeared at 6,129.526ppm, and the next 4-methoxyben was 1,966.714ppm. It was methyl gallate 8.197ppm, 4-hydroxy-3-methoxy benzoic 6.994ppm, caffeic acid 5.566ppm, flavone 4.522ppm, p-coumaric acid 3.787ppm, gallic acid 1.893ppm that appeared in the content below 10ppm.

Efficacy of Chemical Preservatives to Control Perilla Rust

  • Al-Reza, Sharif M.;Hwang, Cher-Won;Kang, Sun-Chul
    • Korean Journal of Environmental Agriculture
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    • v.29 no.4
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    • pp.417-420
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    • 2010
  • The rust fungi are biotrophic fungal pathogens that cause serious disease on Perilla leaves in Korea. The effect of some commonly used chemical preservatives (sorbic acid, D-sorbitol, propionic acid and benzoic acid) against Perilla rust was investigated in this study. Results of this investigation showed that all the preservatives were effective against Perilla rust except benzoic acid. There was no growth of rust spores on the Perilla leaves treated with 0.1% of preservative even after 21 days of preservation. However, 0.01% of preservative also showed remarkable reduction of rust spores on the Perilla leaves as compared to the control groups. Thus, the results of this study indicated that the chemical preservatives used might be useful to control the growth of rust fungi on Perilla leaves.

Simultaneous Determination of Preservatives in Food by GC/MS (Gas Chromatography/Mass Spectrometry를 이용한 식품보존료의 동시분석방법 연구)

  • 김승기;노동석
    • Journal of Food Hygiene and Safety
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    • v.14 no.2
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    • pp.140-145
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    • 1999
  • Analytical method for preservatives in food was developed using gas chromatography/mass spectrometry (GC/MS). Propionic acid, sorbic acid, benzoic acid, ethyl salicylate, ethyl p-hydroxy benzoate, iso-propyl p-hydroxy benzoate, n-propyl p-hydroxy benzoate, iso-butyl p-hydroxy benzoate, n-butyl p-hydroxy benzoate, p-hydroxy benzoic acid and dehydro acetic acid were extracted from cooling beverage with diethyl ether. The polar hydroxyl and carboxyl groups of food preservatives were derivatized with N-methyl-N-tert-butyldimethylisilyl-trifluoroscetamide (MTBSTFA) to form the corresponding tert-bytyldimethyl-silylated derivatives, and submitted to GC/MS analysis. The mass spectra of the derivatives were investigated for the selection of monitoring ions for multi-residue analysis of 11 preservatives by GC/MS. The macro program was also developed for the qualitative analysis of these preservatives in food.

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Studies on the Dissociation Constants of Benzoic Acids in Ethanol-Water Mixtures by Conductometric Method (에탄올-물 혼합용매에서 전도도법에 의한 벤조산의 해리상수에 관한 연구)

  • Min Soo Cho;Soon Ki Lee;Lee, Gye Su
    • Journal of the Korean Chemical Society
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    • v.25 no.2
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    • pp.67-74
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    • 1981
  • The dissociation constants of benzoic acid, p-methoxybenzoic acid and p-nitrobenzoic acid have been determined at $25^{\circ}C$ in ethanol-water mixtures containing 0, 10, 20, 30, 40, 50, 65 and 80 weight % ethanol by the direct conductance measurements and the method involving titration of the acid sample with perchloric acid reagent. The results by the two methods have been discussed and compared with those by other methods.

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Screening of Phenolic Compounds with Inhibitory Activities against HMG-CoA Reductase (페놀 화합물로부터 HMG-CoA reductase 저해 활성 물질 탐색)

  • Son, Kun Ho;Lee, Ju Yeon;Lee, Jeong Soon;Kang, Sam Sik;Sohn, Ho Yong;Kwon, Chong Suk
    • Journal of Life Science
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    • v.27 no.3
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    • pp.325-333
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    • 2017
  • High level of plasma cholesterol is strongly associated with the development of atherosclerosis and coronary heart disease. Clinical trials designed to reduce plasma cholesterol level by diet or pharmacological intervention have resulted in marked reduction of disease incidence. The enzyme 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase which reduces cholesterol biosynthesis in the liver is the key enzyme of the mevalonate pathway that produces cholesterol. In this study, 71 naturally occurring phenolic compounds were tested for inhibitory activities against HMG-CoA reductase. Eleven compounds out of 71 showed inhibitory activities: three hydrolyzable tannin (geraniin, acetonyl geraniin and pentagalloyl ${\beta}-D-glucose$), four benzoic acid derivatives (benzoic acid, trans-cinnamic acid, 2,4-dihydroxybenzoic acid and 2,5-dihydroxybenzoic acid), and four naphthoquinone derivatives (1,2-naphthoquinone, 1,4-naphthoquinone, plumbagin and shikonin). At the concentration of $10{\mu}g/ml$, 1,4-naphthoquinone inhibited HMG-CoA reductase by 99.4%, and then plumbagin 91.4%, pentagalloyl ${\beta}-D-glucose$ 46.6%, 2,4-dihydroxybenzoic acid 40.9%, shikonin 37.7%, 1,2-naphthoquinone 36.6%, trans-cinnamic acid 32.0%, acetonyl geraniin 30.2%, benzoic acid 28.5%, geraniin 28.3% and 2,5-dihydroxybenzoic acid 22.3%, respectively. $IC_{50}$ values of 1,4-naphthoquinone and plumbagin was $2.1{\mu}g/ml$ and $5.8{\mu}g/ml$, respectively.