• Applied Chemistry for Engineering
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• v.22 no.4
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• pp.367-375
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• 2011

Succinic acid ester derivatives have been used as additives for the base oil of metal working fluids and pressure working oils. In this paper, a series of succinic acid alkyl half-esters were synthesized with over 97% yields by ring-opening reaction of succinic anhydride and fatty alcohol and were soluble in 100 N base oil within 1 wt% concentration. The structures and purities of ester derivatives were confirmed by $^1H-NMR$ and FT-IR spectrum and GC analysis. Anti-corrosion properties of the esters in sea water were evaluated through ASTM D665 method and weight loss method and compared to that of succinic alkyl esters without carboxylic acid group in the molecule. As the results, anti-corrosion properties of succinic acid alkyl half-esters with carboxylic acid group were better than those of succinic acid alkyl esters without carboxylic acid group. And, Anti-corrosion properties of the esters with a shorter alkyl chain of high concentration showed better performance than those with longer alkyl chain of low concentration. Inhibition efficiency % (IE%) of the esters was over 95% in the concentration of 80 ppm and corrosion rate (CR) was below 0.3 mm/year at the same concentration. Thus, the corrosion properties of succinic acid alkyl half-esters result from the carboxylic acid groups in molecules.

• Clean Technology
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• v.17 no.4
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• pp.314-324
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• 2011

Several amide derivatives have been used as additives for base oil of metal working fluids and pressure working oils. In this paper, a series of succinic acid alkyl half-amide derivatives were synthesized as over 97% yields by ring-opening reaction of succinic anhydride and several amines and were soluble in 100 N base oil within 1 wt% concentration. The structures of the synthesized amides were confirmed by $^1H$-NMR, FT-IR spectrum and GC analysis. Anti-corrosion properties of the amides in sea water were evaluated through ASTM D665 method and weight loss method. As the results of anti-corrosion properties, the properties of the amides with shorter alkyl chain and high concentration showed better performance than those with longer alkyl chain and low concentration. Also, the dialkyl amides showed better anti-corrosion properties than those of the monoalkyl amides. Inhibition efficiency% (IE%) was over 93% in the concentration of 40 ppm and corrosion rate (CR) was below 0.5 mm/year in the same concentration.

• The Korean Journal of Pesticide Science
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• v.10 no.4
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• pp.237-248
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• 2006

Forty one compounds such as ester, sulfonyl ester, carbamate, ether and phosphoyl ester derivatives of thymol(I) and carvacrol(II) were synthesized. These derivatives were identified by IR, GC/MS and $^1H$-NMR spectra. Their antifungal activities were tested against various plant pathogenicfugi. Among them, several compounds were showed potent in vivo antifungal activities. The selected compounds showing in vitro antifungal activities were tested in vivo antifungal activities aganint 5 plant diseases such as rice blast, rice sheath blight, tomato late blight, cucumber anthracnose, and cucumber gray mold. As a result, 2-isopropyl-5-methylphenylacetate(I-1a) effectively suppressed the development cucumber gray mold and rice blast. Methyl(2-isopropyl-5-methylphenoxy)acetate(I-6d) and ethyl 4-(5-methyl-2-isopopylphenoxy)crotonate(I-7d) also showed potent in vivo antifungal actively againt rice sheath blight and tomato late blight, respectively.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.42 no.2
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• pp.135-143
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• 2016

In this study, we investigated the stability of the liposome formulation containing the phytochemicals-peptide derivatives. Among liposomes prepared using lecithins or surfactant under various conditions, the most stable niosome was obtained by using sodium palmitoyl sarcosinate and macadamia intergrifolia seed oil. The stability of peptide-containing niosome (N9) was confirmed by the TEM images. The N9 was stable at 0 and 45 degrees by Turbiscan, and its particle size was 95.7 nm. The N9 showed zeta potential value of -78.19 mV, and peptide-inclusion rate of 65.2% by BCA assay.

• Journal of Applied Biological Chemistry
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• v.61 no.4
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• pp.423-428
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• 2018

Anaerobic growth-inhibiting and acaricidal activities of 2'-hydroxy-5'-methoxyacetophenone derived from Cyanachum paniculatum oil and its derivatives against five intestinal bacteria (Bifidobacterium bifidum, B. longum, Clostridium pefringens, Escherichia coli and Lactobacillus casei) and Haemaphysalis longicornis were examined. In the packet test against the larvae of H. longicornis, none of the C. paniculatum oil exhibited acaricidal activity, while the C. paniculatum oil showed only antimicrobial activity against five intestinal bacteria in the disc diffusion method. Based on the inhibition zones and MIC values, 2',4'-dimethoxyacetophenone, 2',5'-dimethoxyacetophenone, 2'-hydroxy-4'-methoxyacetophenone, 2'-hydroxy-5'-methoxyacetophenone, 2'-methoxyacetophenone, and 4'-methoxyacetophenone, containing a methyl group on the acetophenone skeleton, possessed growthinhibiting activities against C. perfringens and E. coli. However, acetophenone, 2'-hydroxyacetophenone, 4'-hydroxyacetophenone, 2',4'-hydroxyacetophenone and 2',5'-hydroxyacetophenone, which contained a hydroxyl group on the acetophenone skeleton, had no growth-inhibiting activity against intestinal bacteria. These results indicated that 2'-hydroxy-5'-methoxyacetophenone and its derivatives could potentially be developed as natural antimicrobial agents to specific control of C. perfringens and E. coli.

• Journal of environmental and Sanitary engineering
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• v.10 no.3
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• pp.1.2-8
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• 1995

In the present study the sesamin and sesamol contents of the sesame extracts prepared from nine provinces in Korea were determined HPLC method. A comparative test was also carried out using the Villavecchia-suarez test, the red colored reaction for the sesamol and sesamol derivatives. The contents of sesamin and sesamol of the sesame oils from each area by the HPLC method were 0.57~0.78% and 0.010-0.023%, respectively. and the paralled results were obtained by the Villavecchia-suarez test and the HPLC method. The average contents of the sesamin was $0.68{\pm}0.074%$ by the HPLC method and the average absorbance of the Villavecchia-suarez test was $0.56{\pm}0.034$. The contents of sesamol from sesame oil by the HPLC method and the Villavecchia-suarez test were so low that it was not possible to correlate with the sesamin contents. The contents of sesamol from the sesame oil produced in Kyeong-gi and Jeon-nam provinces were $0.010{\pm}0.002%$ and $0.023{\pm}0.004$, respectively.

• Food Science and Biotechnology
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• v.18 no.5
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• pp.1224-1229
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• 2009

The main objective of this study was to investigate possible application of citron (Citrus junos Sieb. ex TANAKA) seeds, which are massively produced as by-products during citron tea process, into functional food materials. First of all, citron seeds were germinated and produced citron shoots were examined for their functional properties. When contents of flavonoids in citron seeds and their germinated shoots were compared, naringenin, neohesperitin, and hesperitin were remarkably increased in shoots after germination while naringin and didymin were decreased. Concentrations of limonin and nomilin were decreased by germination otherwise their unidentified derivatives were newly formed. A methanol extract of citron shoot had lower $IC_{50}$ values [0.13 and 0.07 mg/mL for 2,2-diphenyl-1-picryl-hydrazyl (DPPH) and ABTS, respectively] than citron seed extract in radical scavenging activities. Addition of 500 mg/mL of citron shoot extract suppressed fat accumulation in 3T3-L1 adipocytes by 36.9%. Oral administration of olive oil along with citron shoot extract (33 mg/kg body weight) to Sprague Dawley rats effectively inhibited absorption of lipid into a body by decreasing blood triglyceride levels from 105.1 to 74.9 mg/dL 2 hr after olive oil administration. According to these results, citron shoot extract as a rich source of flavonoids can be utilized for functional food ingredients with effective antioxidant and anti-adipogenic properties.

• Corrosion Science and Technology
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• v.16 no.2
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• pp.85-89
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• 2017

One of the most challenging issues in the oil and gas industry is corrosion assessment and management in subsea structures or equipment. At present, almost all steel pipelines are sensitive to corrosion in harsh working environments, particularly in salty water and sulphur ingress media. Nowadays, the most commonly practiced solution for a damaged steel pipe is to entirely remove the pipe, to remove only a localized damaged section and then replace it with a new one, or to cover it with a steel patch through welding, respectively. Numerous literatures have shown that fiber-reinforced polymer-based composites can be effectively used for steel pipe repairs. Considerable research has also been carried out on the repair of corroded and gouged pipes incorporated with hybrid natural fiber-reinforced composite wraps. Currently, further research in the field should focus on enhanced use of the lesser and highly explored hybrid-biocomposite material for the development in corrosion prevention. A hybrid-biocomposite material from renewable resource based derivatives is cost-effective, abundantly available, biodegradable, and an environmentally benign alternative for corrosion prevention. The aim of this article is to provide a comprehensive review and to bridge the gap by developing a new hybrid-biocomposite with superhydrophobic surfaces.

• Archives of Pharmacal Research
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• v.22 no.3
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• pp.279-287
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• 1999

Therapeutic use of anti-inflammatory steroids is limited due primarily to their systemic suppressive effects on pituitary function and the immune system.. To overcome the clinical limitation, a new approach toward the discovery of non-systemic anti-inflammatory steroids is based upon the antedrug concept introduced by this laboratory. The new concept describes locally active agents which are designed to undergo a predictable biotransformation to inactive metabolites upon entry into systemic circulation from the applied site. Thus, true antedrugs are devoid of systemic adverse effects. In a continuing effort, 16$\alpha$-carboxylate and isoxazoline derivatives of prednisolone have been synthesized and screened. In the croton oil-induced ear edema bioassay, the following relative potencies were obtained setting hydrocortisone=1.0; 3a, 1.5; 3b, 3.1; 4a, 4.0; 4b, 12.2; 5b, 8.2; 6b, 11.2; 7a, 1.9; 7b, 4.1; 8a, 3.3; 8b 6.8; 9a, 0.7; 9b 8.6; 10a 2.6; 10b, 7.4. Results of the five-day bioassay indicated that, in contrast to the parent compound, the novel steroidal antedrugs did not significantly alter body weight gain, thymus weights, adrenal weights or plasma corticosterone levels. Taken together, the antedrug concept appears to be a fundamentally sound strategy for the separation of local anti-inflammatory activity form systemic adverse effects.

• Korean journal of food and cookery science
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• v.25 no.4
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• pp.488-495
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• 2009

Pork cutlet is a favorite deep fat fried food item among Korean children, and an excellent protein-containing food, and as well as a simple and economical cuisine. However, the frying process adds a significant amount of calories. We added MC (Methylcellulose) and HPMC (Hydroxypropyl Methylcellulose) to the batter in an effort to reduce oil uptake in prepared pork cutlets. After additions of MC and HPMC at concentrations of 0.5, 1, and 1.5% respectively, we assessed the viscosity of batter, color after frying, the increases in moisture retention and oil uptake, and sensory characteristics, comparing each quality. The viscosity of batter with 0.5% HPMC added (w/w) was similar to that of the controls, but the viscosity of all the batter with added MC was so much higher that it was difficult to use the batter for coating at the same temperature, leading to a failure even to prepare a sample. After frying, the batter with added HPMC provided significantly less oil uptake and more moisture retention than the batter to which MC was added. Additionally, with regard to color and sensory characteristics, the pork cutlet with 0.5% added HPMC was superior to the other samples. According to these results, we concluded that when cellulose derivatives are added in order to reduce oil uptake and to raise the moisture retention of the batter of pork cutlet, HPMC is more useful in this regard than MC. Additionally, the batter with 0.5% HPMC added appears to be the best of the tested choices, for three reasons: first, the viscosity of the batter is similar to that of the controls; second, the taste is not greasy after frying as the result of the reduced oil uptake and higher moisture retention; and third, the sensory characteristics of this sample, such as, color, crispiness, and hardness were the best among samples.