• Title/Summary/Keyword: ester

Search Result 2,600, Processing Time 0.031 seconds

Properties of Liquid Crystalline Polyester/Poly(ethylene 2,6-naphthalate) Blend Fibers (액정 폴리에스테르/PEN 블렌드 섬유의 성질)

  • Kim, Won;Kim, Young-Yong;Son, Jung-Sun;Yun, Doo-Soo;Han, Chul;Choi, Jae-Kon;Jo, Byung-Wook
    • Elastomers and Composites
    • /
    • v.37 no.4
    • /
    • pp.244-257
    • /
    • 2002
  • A thermotropic liquid crystalline polymer(TLCP) which has flexible butylene/hexylene spacers in the main chain and a triad aromatic ester type mesogenic unit containing a naphthyl group was prepared by solution polycondensation. The in-situ composites based on poly(ethylene 2,6-naphthalate) (PEN) and a thermotropic liquid crystalline polymer(TLCP) were prepared and melt spun at different TLCP contents and different draw ratios to produce monofilaments. Blends of the TLCP with PEN were investigated in terms of thermal, mechanical properties and morphology. The TLCP synthesized showed nematic mesophasic behavior and its transition temperature to isotropic melt from mesophase was 249℃. The blends showed well dispersed TLCP phases in the PEN matrix without macroscopic phase separation. Inclusion of TLCP in the blends decreased the cold crystallization temperature of PEN in the blend, therefore, the TLCP acts as a nucleating agent in the blend and showed good interfacial adhesion between the dispersed LCP phases and PEN matrix with domain sizes 40~50 nm in diameter and well developed fibrillation in the monofilaments. The TLCP acted effectively as a reinforcing material in the PEN matrix at the 10wt% level, it led to an increase of initial modulus up to 270% and tensile strength by 235%, while the elongation rate increasing with higher draw ratios.

Analysis of Mineral and Volatile Flavor Compounds in Pimpinella brachycarpa N. by ICP-AES and SDE, HS-SPME-GC/MS (ICP-AES와 SDE, HS-SPME-GC/MS를 이용한 참나물의 무기성분과 향기성분)

  • Chang, Kyung-Mi;Chung, Mi-Sook;Kim, Mi-Kyung;Kim, Gun-Hee
    • Journal of the Korean Society of Food Culture
    • /
    • v.22 no.2
    • /
    • pp.246-253
    • /
    • 2007
  • Mineral and volatile flavor compounds of Pimpinella brochycarpa N., a perennial Korean medicinal plant of the Umbelliferae family, were analyzed by inductively coupled plasma-atomic emission spectroscopy (ICP-AES) and simultaneous steam distillation extract (SDE)-gas chromatography mass spectrometry (GC/MS), head space solid phase micro-extraction (HS-SPME)-GC/MS. Mineral contents of the stalks and leaves were compared and the flavor patterns of the fresh and the shady air-dried samples were obtained by the electronic nose (EN) with 6 metal oxide sensors. Principal component analysis (PCA) was carried out using the data obtained from EN. The 1st principal values of the fresh samples have + values and the shady air-dried have - values. The essential oil extracted from the fresh and the shady air-dried by SDE method contain 58 and 31 flavor compounds. When HS-SPME method with CAR/PDMS fiber and PDMS fiber were used, 34 and 21 flavor compounds. The principal volatile components of Pimpinella brachycarpa N. were ${\alpha}$-selinene, germacrene D, and myrcene.

Purple perilla frutescens extracts containing α-asarone inhibit inflammatory atheroma formation and promote hepatic HDL cholesterol uptake in dyslipidemic apoE-deficient mice

  • Sin-Hye Park;Young Eun Sim;Min-Kyung Kang;Dong Yeon Kim;Il-Jun Kang;Soon Sung Lim;Young-Hee Kang
    • Nutrition Research and Practice
    • /
    • v.17 no.6
    • /
    • pp.1099-1112
    • /
    • 2023
  • BACKGROUND/OBJECTIVES: Dyslipidemia causes metabolic disorders such as atherosclerosis and fatty liver syndrome due to abnormally high blood lipids. Purple perilla frutescens extract (PPE) possesses various bioactive compounds such as α-asarone, chlorogenic acid and rosmarinic acid. This study examined whether PPE and α-asarone improved dyslipidemia-associated inflammation and inhibited atheroma formation in apolipoprotein E (apoE)-deficient mice, an experimental animal model of atherosclerosis. MATERIALS/METHODS: ApoE-deficient mice were fed on high cholesterol-diet (Paigen's diet) and orally administrated with 10-20 mg/kg PPE and α-asarone for 10 wk. RESULTS: The Paigen's diet reduced body weight gain in apoE-deficient mice, which was not restored by PPE or α-asarone. PPE or α-asarone improved the plasma lipid profiles in Paigen's diet-fed apoE-deficient mice, and despite a small increase in high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein (LDL)-cholesterol, and very LDL were significantly reduced. Paigen's diet-induced systemic inflammation was reduced in PPE or α-asarone-treated apoE-deficient mice. Supplying PPE or α-asarone to mice lacking apoE suppressed aorta atherogenesis induced by atherogenic diet. PPE or α-asarone diminished aorta accumulation of CD68- and/or F4/80-positive macrophages induced by atherogenic diet in apoE-deficient mice. Treatment of apoE-deficient mice with PPE and α-asarone resulted in a significant decrease in plasma cholesteryl ester transfer protein level and an increase in lecithin:cholesterol acyltransferase reduced by supply of Paigen's diet. Supplementation of PPE and α-asarone enhanced the transcription of hepatic apoA1 and SR-B1 reduced by Paigen's diet in apoE-deficient mice. CONCLUSIONS: α-Asarone in PPE inhibited inflammation-associated atheroma formation and promoted hepatic HDL-C trafficking in dyslipidemic mice.

[RETRACTED] Changes in the volatile aromatic compounds and amino acid contents of distilled soju using co-fermentation by Saccharomyces cerevisiae and Hanseniaspora uvarum yeasts ([논문철회] Saccharomyces cerevisiae 와 Hanseniaspora uvarum 효모 혼합발효를 이용한 증류식 소주의 휘발성 향기성분 및 아미노산 함량 변화)

  • Kyu-Taek Choi;Chun-Woo Park;Su-Hyun Lee;Ye-Na Lee;Ji-Yun Oh;Jun-Su Choi;Deokyeong Choe;Sae-Byuk Lee
    • Food Science and Preservation
    • /
    • v.30 no.6
    • /
    • pp.1029-1042
    • /
    • 2023
  • This study aimed to apply the technology of increasing the volatile aromatic compounds in wine through mixed fermentation of Saccharomyces cerevisiae and non-Saccharomyces yeasts to make distilled soju. The expectation was to induce changes in metabolites such as volatile aromatic compounds before the distillation process, followed by concentrating these compounds through distillation to enhance the odor property of distilled soju. Additionally, the study aimed to examine the impact of mixed fermentation with S. cerevisiae and non-Saccharomyces yeasts on distilled soju's free amino acid content. As a result, when Hanseniaspora uvarum yeast was used, there was an increase in the content of low molecular weight volatile aroma compounds, particularly esters. Distilled soju co-fermented with S. cerevisiae and H. uvarum SJ69 exhibited similar amino acid content to distilled soju single-fermented with S. cerevisiae. However, distilled soju co-fermented with S. cerevisiae and H. uvarum S6, a decrease in amino acid content. Sensory evaluation results indicated a higher odor score in distilled soju co-fermented with S. cerevisiae and H. uvarum S6, suggesting that the mixed fermentation technology utilizing H. uvarum could contribute to improving the quality of distilled soju in the future.

Rosmarinic Acid Inhibits Ultraviolet B-Mediated Oxidative Damage via the AKT/ERK-NRF2-GSH Pathway In Vitro and In Vivo

  • Mei Jing Piao;Pattage Madushan Dilhara Jayatissa Fernando;Kyoung Ah Kang;Pincha Devage Sameera Madushan Fernando;Herath Mudiyanselage Udari Lakmini Herath;Young Ree Kim;Jin Won Hyun
    • Biomolecules & Therapeutics
    • /
    • v.32 no.1
    • /
    • pp.84-93
    • /
    • 2024
  • Rosmarinic acid (RA) is a phenolic ester that protects human keratinocytes against oxidative damage induced by ultraviolet B (UVB) exposure, however, the mechanisms underlying its effects remain unclear. This study aimed to elucidate the cell signaling mechanisms that regulate the antioxidant activity of RA and confirm its cyto-protective role. To explore the signaling mechanisms, we used the human keratinocyte cell line HaCaT and SKH1 hairless mouse skin. RA enhanced glutamate-cysteine ligase catalytic subunit (GCLC) and glutathione synthetase (GSS) expression in HaCaT cells in a dose- and time-dependent manner. Moreover, RA induced nuclear factor erythroid-2-related factor 2 (NRF2) nuclear translocation and activated the signaling kinases protein kinase B (AKT) and extracellular signal-regulated kinase (ERK). Treatment with the phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002, the ERK inhibitor U0126, and small interfering RNA (siRNA) gene silencing suppressed RA-enhanced GCLC, GSS, and NRF2 expression, respectively. Cell viability tests showed that RA significantly prevented UVB-induced cell viability decrease, whereas the glutathione (GSH) inhibitors buthionine sulfoximine, LY294002, and U0126 significantly reduced this effect. Moreover, RA protected against DNA damage and protein carbonylation, lipid peroxidation, and apoptosis caused by UVB-induced oxidative stress in a concentration-dependent manner in SKH1 hairless mouse skin tissues. These results suggest that RA protects against UVB-induced oxidative damage by activating AKT and ERK signaling to regulate NRF2 signaling and enhance GSH biosynthesis. Thus, RA treatment may be a promising approach to protect the skin from UVB-induced oxidative damage.

Type of Oil and Effect of Required HLB on Nanoemulsion Formation (오일의 종류 및 required HLB가 나노에멀젼 형성에 미치는 영향)

  • Da-yeon Lee;Hye-yun Hwang;Su-min Lim;Hy-ein Jang
    • Journal of the Korean Applied Science and Technology
    • /
    • v.40 no.6
    • /
    • pp.1533-1546
    • /
    • 2023
  • Nanoemulsion is an emulsion with a particle size of about 20 ~ 200 nm and has the advantage of having a transparent or translucent appearance and improving the skin permeability of an effective material with a small particle size, so it is applied in various fields. In this study, eight oils with different types of HLB and 16 oils with different types of required HLB were selected to investigate the effect of the required HLB and the type on the formation of nanoemulsion. The surfactants used at this time were Polysorbate 60 (HLB 14.9), Sorbitan state (HLB 4.7), PEG-60 hydrogenated castor oil (HLB 14.0), which were mixed with Polysorbate 60 and Sorbitan state, fixed with HLB 14.0, and Polysorbate 60 and PEG-60 hydrogenated castor oil, respectively. The formation of nanoemulsion was different depending on the type of oil, and oil with an ester structure showed a relatively excellent nanoemulsion formation ability. In particular, it was confirmed that a stable nanoemulsion was formed without a significant change after Cetyl ethylhexanoin was produced in a small size of 40 nm or less on average. In addition, it was found that using a mixture of Polysorbate 60 and Sorbitan stearate has a superior nanoemulsion formation ability than using PEG-60 hydrogenated castor oil or Polysorbate 60 alone.

Evaluation of Quality Standards of Bio-Diesel (BD100, BD20) Manufactured Using Waste Frying Oil (폐식용유를 이용하여 제조한 바이오디젤(BD100, BD20)의 품질기준 평가)

  • Na, Seong-Joo;Jeon, Byung-Gwan
    • Journal of the Korea Organic Resources Recycling Association
    • /
    • v.17 no.1
    • /
    • pp.39-48
    • /
    • 2009
  • Biodiesel is estimated to be the best recycling energy source as an alternative fuel for transportation vehicles which represents the biggest share of greenhouse effect gas exhausts. Thus, in order to widely expand use of biodiesel and to enhancement its reliability, studies on quality improvement of biodiesel is needed. In this study, we have produced biodiesel(BD100, BD20) through esterification reaction using raw material of waste frying oil and analyzed compatibility with 24 items of quality criteria. As waste frying oil has high contents of unsaturated fatty acid such as Oleic acid, Linoleic acid and Linolenic acid, it is confirmed that there is no problem in using the same as a raw material of biodiesel. The result of analyzing the quality criteria items of biodiesel showed that it satisfied all the quality criteria except the oxidation stability of BD100, which was 2 hours, fatty acid methyl ester of BD20, which was 18.6w% and the filter plugging point, which was $-5^{\circ}C$. We believe that it will contribute to improved utilization of waste resources as alternative energy if studies on technology to improve quality of some items are provided.

Food Components of Wild and Cultured Fresh Water Fishes (천연 및 양식산 담수어의 식품성분)

  • KIM Kyung-Sam;LEE Eung-Ho
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.19 no.3
    • /
    • pp.195-211
    • /
    • 1986
  • The object of this study is to obtain fundamental data on cultured fishes produced in Korea to improve their food components. For this purpose, the food components of cultured fresh water fishes such as eel, Anguilla japonica, snakehead, Channa argus, and common carp, Cyprinus carpio, were investigated and compared with those of the wild ones. The results obtained are summarized as follows: 1. Common characteristics in the proximate composition were that wild fish was higher in crude protein content and lower in crude lipid content than those of cultured one. 2. Among the 9 kinds of minerals analyzed in all the samples, sodium, potassium, calcium and magnesium contents were absolutely predominant being more than $99.52\%$. These four elements in feedstuff also occupied $99.68{\sim}99.92%$ of total minerals. 3. The neutral lipids of wild and cultured eel, snakehead and common carp occupied $55.7{\sim}95.8%$ of lipid fractions, while the content of the phospholipids in snakehead was particularly higher than those of others. 4. The neutral lipids of wild and cultured eel, snakehead and common carp mainly consisted of triglycerides ($85{\sim}95%$), and a little quantity of diglycerides, monoglycerides, free sterol ester and hydrocarbon were also identified in the neutral lipid. 5. The phospolipids of eel and common carp were mainly occupied by phosphatidyl choline ($71.3{\sim}83.9%$), followed by phosphatidyl ethanolamine ($12.1{\sim}23.5%$) and phosphatidyl serine ($7.5{\sim}13.8%$). The phospholipids of snakhead consisted of phosphatidyl choline ($50.7{\sim}64.5%$), phosphatidyl ethanolamine ($28.0{\sim}35.5%$) and phosphatidyl serine ($7.5{\sim}13.8%$). Generally, phosphatidyl choline content was higher in wild fish than in cultured one, while phosphatidyl ethanolamine and phosphatidyl serine contents were higher in cultured one. 6. The major fatty acids in total lipid of wild eel, snakehead and common carp were $C_{16:0}\;and\;C_{20:5}$, while those in cultured ones were $C_{18:1},\;C_{18:2}\;and\;C_{22:6}$. The fatty acid composition of neutral lipids showed similar tendency to that of total lipid, and the main fatty acids in phospholipids of cultured fishes were $C_{18:1}\;and\;C_{18:2}$. In glycolipids, $C_{20:5}\;and\;C_{22:6}$ were higher in wild fishes, while $C_{18:2}$ were higher in cultured ones. 7. Total amino acids contents of wild and cultured eel were nearly the same, being $16.65\%$ ana $15.99\%$ respectively. The major amino acids of wild and cultured fish were glutamic acid, leucine, aspartic acid and lysine in order. In snakehead, the contents of aspartic acid and proline in cultured fish were higher than those in wild one, while the contents of glutamic acid, alanine, glycine were higher in the wild one. Total amino acid content of cultured common carp was $21.7\%$ compared with $17.08\%$ in wild one. The contents of glutamic acid, aspartic acid, glycine, proline and alanine occupied higher quantities in cultured common carp compared with those in wild one while the other amino acids revealed no significant difference. 8. Aspartic acid in free amino acids of cultured eel held $1.0\%$ of total free amino acids, while that in wild eel held $2.9\%$. Histidine, arginine and tyrosine content of cultured fish were two times higher than those of wild one. But free amino acid composition of samples seemed to be no marked differences according to cultured places. The contents of arginine, aspartic acid, glutamic acid, methionine and phenylalanine of snakehead ware higher in wild one than in cultured one, while the contents of lysine, histidine, glycine, and alanine ware higher in cultured one. In free amino acids content of wild common carp, histidine, glycine and lysine occupied $76.9\%$ of total free amino acids. Lysine, histidine, aspartic acid, alanine, valine and leucine were higher in wild one compared with those of cultured one, while glycine and tyrosine contents were higher in cultured fish.

  • PDF

Studies on the Development of Food Resources from Waste Seeds -II. Chemical Composition of Apple Seed- (폐기종실(廢棄種實)의 식량자원화(食糧資源化)에 관(關)하여 -제(第) 2 보(報) : 사과씨의 화학적(化學的) 조성(組成)-)

  • Yoon, Hyung-Sik;Choi, Cheong;Oh, Man-Jin
    • Korean Journal of Food Science and Technology
    • /
    • v.15 no.2
    • /
    • pp.128-132
    • /
    • 1983
  • The apple seed contained 25.96% of crude fat and 37.62% of crude protein. The lipid fractions obtained by cilicic column chromatography were mainly composed of about 93.52% neutral lipid, whereas compound lipid was only 6.48% level. Among the neutral lipid separated by thin layer chromatography, triglyceride was 92.17%, sterol ester, sterol, diglyceride and free fatty acid were 3.53, 2.25, 1.44 and 0.56, respectively. The predominent fatty acids of total and neutral lipids were linoleic acid (59.79-69.37%) and oleic acid (20.04-29.82%), but those of glycolipid and phojspholipid were linoleic acid (29.20-36.04%). The major fatty acids of triglyceride separated from neutral lipid were oleic acid (44.31%), linoleic acid (36.66%) and palmitic acid (12.48%). The salt soluble protein of apple seed was highly dispersible in 0.02M sodium phosphate buffer containing about 1.0M $MgSO_4$, and the extractability of seed protein was 37%, Glutamic acid was the major amino acid in salt soluble protein, followed by arginine and aspartic acid. The eletrophoretic analysis showed three bands in apple seed protein, and the collection rate of the main protein fraction purified by Sephadex G-100 and G-200 was 76.6%. Glutamic acid, aspartic acid and arginine were the major amino acids of the main apple seed protein. The molecular weight for the main protein of the apple seed was estimated to be 45,000.

  • PDF

Thermotropic Liquid Crystalline and Photochemical Phase Transition Behavior of Octa[8-{4-(4'-cyanophenylazo)phenoxy}]octyl and Octa[8-{4-(4'-cyanophenylazo) phenoxycarbonyl}]heptanoated Disaccharides (옥타[8-{4-(4'-시아노페닐아조)펜옥시}]옥틸 그리고 옥타[8-{4-(4'-시아노페닐아조) 펜옥시카보닐}]헵타노화 이당류의 열방성 액정과 광화학적 상전이 거동)

  • Kim, Hyo Gap;Jung, Seung Yong;Jeong, Hee Sung;Ma, Yung Dae
    • Polymer(Korea)
    • /
    • v.36 no.6
    • /
    • pp.776-788
    • /
    • 2012
  • Octa[8-{4-(4'-cyanophenylazo)phenoxy}]octyl and octa[8-{4-(4'-cyanophenylazo)phenoxycarbonyl}]heptanoated disaccharide derivatives were synthesized by reacting cellobiose, maltose, and lactose with 1-{4-(4'-cyanophenylazo) phenoxy}octylbromide or 1-{4-(4'-cyanophenylazo)phenoxycarbonyl}]heptanoyl chloride, and their thermotropic liquid crystalline and photochemical phase transition behavior were investigated. All the {(cyanophenylazo)phenoxy} octyl disaccharide ethers (CADETs) formed monotropic nematic (N) phases, whereas all the {(cyanophenylazo) phenoxycarbonyl}heptanoated disaccharide esters (CADESs) exhibited enantiotropic N phases. Compared with CADETs, CADESs showed higher isotropic (I)-to-N phase transition temperatures. Photoirradiation of the disaccharide derivatives in a glass cell or in a cell with a rubbed polyimide (PI) alignment layer at a N phase resulted in disappearance of the N phase due to trans-cis photoisomerization of azobenzene, and the initial N phase was recovered when the irradiated sample was kept in the dark because of cis-trans thermal isomerization and reorientation of trans-azobenzenes. The rates of the photochemical N-I and the thermal I-N phase transition of disaccharide derivatives in a cell with a rubbed PI alignment layer were faster than those in a glass cell, and were significantly different from those observed for the monomesogenic compounds containing cyanoazobenzene and the 4-{4'-(cyanophenylazo)phenoxy}octyl glucose and cellulose ethers. The results were discussed in terms of difference in cooperative motion of azobenzene groups due to the flexibility of the main chain, the number of mesogenic units per repeating units, and the distance between the azobenzene groups.