• Title/Summary/Keyword: hydroxyl value

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Effect of fermented blueberry on the oxidative stability and volatile molecule profiles of emulsion-type sausage during refrigerated storage

  • Zhou, Hengyue;Zhuang, Xinbo;Zhou, Changyu;Ding, Daming;Li, Chunbao;Bai, Yun;Zhou, Guanghong
    • Asian-Australasian Journal of Animal Sciences
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    • v.33 no.5
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    • pp.812-824
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    • 2020
  • Objective: The aim of this work was to assess the effect of fermented blueberry (FB; 2%, 4%, and 6%) on the oxidative stability and volatile molecule profiles of emulsion-type sausage stored at 4℃ for 28 days. Methods: The antioxidant activity of FB was determined through radical-scavenging activity against 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl radicals. Four formulations of sausage treatments with different FB levels (0%, 2%, 4%, 6%) were prepared, then peroxide value (POVs), thiobarbituric acid-reactive substances (TBARS) values, protein carbonyls and thiol groups were measured. The aroma profiles of sausages for each treatment was also determined. Results: The half maximal inhibitory concentration indicated that FB had greater scavenging ability than ascorbic acid against DPPH and hydroxyl radicals. Sausages with FB significantly retarded increases in POVs and TBARS, as well as in the content of protein carbonyls during all storage days (p<0.05). Particularly, 4% and 6% FB-treated sausages had better oxidation inhibition effects. However, FB accelerated the reduction in thiol groups (p<0.05). Additionally, FB inhibits the excessive formation of aldehyde compounds; for example, hexanal, which may cause rancid flavors, decreased from 58.25% to 19.41%. FB also created 6 alcohols (i.e., 2-methyl-1-propanol, 3-methyl-1-butanol, and phenylethyl alcohol), 5 ester compounds (i.e., ethyl acetate, ethyl lactate, and ethyl hexanoate) and 3-hydroxy-2-butanone in the sausages that contribute to sausage flavors. The principal component analysis showed that the aroma profiles of sausages with and without FB are easily identified. Conclusion: The addition of FB could significantly reduce the lipid and protein oxidation and improve oxidative stability for storage. Also, adding FB could inhibit rancid flavors and contribute to sausage flavors.

Recovery of Covalently Linked Fatty Acid Monolayer on the Hair Surface Using Biomimetic Lipid (생체모사 지질을 이용한 모발 표면에 공유 결합된 지방산 단분자층의 회복)

  • Kim, Ei-Suk;Son, Seong-Kil;Lee, Cheon-Koo
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.38 no.2
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    • pp.139-145
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    • 2012
  • There is a unique type of fatty acid in the hair surface. 18-methyleicosanoic acid (18-MEA) is an unusual anteiso fatty acid covalently linked to the outermost surface of hair cuticle. A layer of 18-MEA is located in the upper ${\beta}$-layer of the CMC that is responsible for the low surface energy and low friction resistance of the hair's outer surface. The high mobility of 18-MEA molecule facilitates spreading of extraneous lipid by decreasing interfacial shear strength. In this study, we introduced N-hydroxyl succinimidyl ester functional group to the one end of C10 - 40 isoalkyl acid for regenerating hair surface with covalently bound fatty acid layer. The re-hydrophobicization of hair surface has been investigated by contact angle measurement. The inner moisture content of hair at different levels of humidity (40, 55, 70 %RH) was measured by electric moisture analyzer. Treatment with Hydroxysuccinimidyl C10 - 40 Isoalkyl Acidate (HCIA) was supposed to make hair surface smoother by filling the cracks between cuticles with covalently bound fatty acid monomolecular layer like cuticle glue. This glue effect was also confirmed with line profile of AFM images. Therefore, the moisture and structural components of inner hair were not easily flown out and the optimum moisture content could be kept constantly though the outside humidity level was changed. The lateral force microscopy (LFM) by using atomic force microscope showed that the friction force of hair surface treated with HCIA was decreased. It also showed the constantly sustained friction value even after shampooing repeated 15 times.

Antioxidant Activities and Quality Characteristics of Jelly Added with Saengmaegsan Concentrate (생맥산 농축액의 양을 달리하여 제조한 젤리의 품질 특성 및 항산화성)

  • Kim, Hyun Jeong;Hong, Seul Kee;Min, A Young;Shin, Suk Kyung;Sim, Eun Kyoung;Yoon, Jun Hwa;Kim, Mee Ree
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.44 no.3
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    • pp.393-400
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    • 2015
  • In this study, antioxidant activities and quality characteristics of gelatin jelly prepared with different amounts (0, 25, 50, and 75%) of saengmaegsan concentrate (SC) were investigated. As the concentration of SC increased, the pH level of SC-added jelly decreased while acidity increased. Hunter a (redness) value of jelly increased as the amount of SC increased, whereas L (lightness) and b (yellowness) values decreased. Texture properties for springiness and resilience were higher in the SC-added groups compared to those of control. Moreover, antioxidant activities such as DPPH radical and hydroxyl radical scavenging activities increased according to increase of SC amount. Total phenol content was the highest in 75% SC-added jelly. Regarding overall preference of sensory properties, 50% SC-added jelly showed the highest scores among all treatments. From these results, the optimal amount of SC was 50% for preparation of high quality jelly.

Comparative Study of the Antioxidative Potential of Common Natural Flavonoids and Isoflavonoids (천연물인 플라보노이드와 이소플라보노이드의 항산화 효과 비교연구)

  • Pandey, Ramesh Prasad;Koirala, Niranjan;Lee, Joo Ho;Lee, Hei Chan;Sohng, Jae Kyung
    • Microbiology and Biotechnology Letters
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    • v.41 no.3
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    • pp.367-371
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    • 2013
  • The half maximal inhibitory concentration ($IC_{50}$) values and trolox equivalent antioxidant capacity (TEAC) values were calculated by a 2,2'-diphenylpicrylhydrazyl (DPPH) assay and a 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid ($ABTS^{+{\cdot}}$) assay, in order to determine the antioxidative activities of the compounds. On the basis of the DPPH assay, quercetin had the strongest antioxidative potential of the flavonoids, followed in order by fisetin, 7,8-dihydroxyflavone, morin and kaempferol. Quercetin, fisetin and 7,8-dihydroxyflavone had higher antioxidant potentials than butyl hydroxyl anisole. Quercetin had the highest TEAC value amongst the flavonoids and isoflavonoids, followed in order by 3-hydroxyflavone, fisetin, 7,8-dihydroxyflavone and morin. Comparatively, isoflavonoids were found to have significantly weaker antioxidative potential than the flavonoids.

Chemical Structure of the Major Color Component from a Korean Pigmented Rice Variety (한국산 유색미에서 분리한 안토시아닌의 화학구조)

  • Cho, Man-Ho;Paik, Young-Sook;Yoon, Hye-Hyun;Hahn, Tae-Ryong
    • Applied Biological Chemistry
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    • v.39 no.4
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    • pp.304-308
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    • 1996
  • The major color component of a Korean pigmented rice (Oeyza sativa var. Suwon 415) was purified with Amberlite XAD-7 column and preparative paper chromatography. The purified pigment was determined as anthocyanin by paper chromatography, UV/Vis and NMR spectroscopy. The $\lambda_{max}$ of the Purified anthocyanin on UV/Vis spectrum were 529 nm and 281 nm. The $A_{440}/A_{529}$ value of the purified anthocyanin was 23% suggesting the presence of 3-glycosidic structure. The aglycone from acid hydrolysis showed bathochromic shift (18 nm) in the presence of $AlCl_3$ indicating that the anthocyanidin contained free adjacent hydroxyl groups such as cyanidin, delphinidin, petunidin or luteolinidin. The sugar moiety obtained from acid hydrolysis was determined as glucose by paper chromatography. The NMR spectra showed that the aglycone was cyanidin and the sugar was ${\beta}-D-glucopyranose$. Thus, the chemical structure of the purified anthocyanin was identified as cyanidin $3-O-{\beta}-D-glucopyranoside$.

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Effects of Equivalent Weight of Epoxy Resins and Content of Catalyst on the Curing Reaction in Cationic Catalyst/Epoxy Cure System (양이온 촉매/에폭시 경화계에서 에폭시 수지의 당량 및 촉매 함량이 경화반응에 미치는 영향)

  • Kim, Youn Cheol;Park, Soo-Jin;Lee, Jae-Rock
    • Applied Chemistry for Engineering
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    • v.8 no.6
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    • pp.960-966
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    • 1997
  • The effects of epoxy resins and content of catalyst on the cure characteristics were studied by FT-IR, DSC and dynamic viscometer for the thermal properties and rheological properties of the catalytic (N-Benzylpyrazinium hexafluoroantimonate, BPH) epoxy thermosetting system. Compared with DSC results of DEGBF containing 0.5wt% BPH, the DSC thermograms of DGEBA containing 0.5wt% BPH indicated that the reaction was faster than that of DGEBF/BPH and the conversion rate of DGEBA/BPH was high in the initial stage of the reaction. As the concentration of BPH increases, the reaction and conversion rates show similar value in both the cases. The influence of hydroxyl group of epoxy resin on gel point defined from the crossover point of storage modulus (G') and loss modulus (G") could be explained by the formation of 3-dimensional network in the initial stage owing to the curing reaction between epoxides and hydroxyl groups of epoxy resin. This was consistent with the gel point obtained from DSC, FT-IR and moduli crossover. The activation energy (Et) obtained from the crossover point (G'/G"=1) are $31-39kJ.mol^{-1}$ for various BPH compositions in case of two epoxy systems.

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The Reactivity of Different Polyols for Paint to Polyisocyanate (도료용 폴리올 종류에 따른 폴리이소시아네이트와의 반응성)

  • Seo, Seok-Hwan;Suh, Cha-Soo;Park, Jin-Hwan
    • Applied Chemistry for Engineering
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    • v.19 no.4
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    • pp.388-396
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    • 2008
  • 2 Components polyurethane coatings are widely used for the industrial coating in general because of its excellent film performance and the workability which were brought by the 3 dimensional cross linked chain structures being formed after the reaction between polyol and polyisocyanate. 2 components polyurethane can be classified into alkyd polyol, polyester polyol, acrylic polyol and polyester modified acrylic polyol depending on where it is used. This research was conducted under the conditions below; different chemical compositions of resin for paint, set the same conditions of viscosity, thinner and acid value, set alternative polyols, OH values and catalysts, set alternative polyisocyanate hardeners of the paint, measure the reaction rates and dynamic mechanical characteristics using RPT-3000, Rotation Rheometer, DMA and FTIR. The research found that the reactivity between polyol and isocyanate influences the film performance and workability depending on the catalysts, OH values and chemical compositions. We find out that different reaction rate of acrylic polyol and polyester modified acrylic polyol with poly-isocyanate is not influenced on temperature and catalyst. In addition, reaction speed of high hydroxyl content polyol is faster than low hydroxyl equivalent. These results can improve difficult working condition to apply urethane coating.

Effect of Hydropsyche kozhantschikovi Extracts on Oxidative Stress (줄날도래 추출물이 산화적 스트레스에 미치는 영향)

  • Park, Young Mi;Lim, Jae Hwan;Lee, Jong Eun;Seo, Eul Won
    • Journal of Life Science
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    • v.23 no.1
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    • pp.31-37
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    • 2013
  • The present study aimed to investigate effects of ethanol extracts from Hydropsyche kozhantschikovi on cell and DNA damage caused by oxidative stress. In a radical scavenging assay, compared with ascorbic acid used as a control, the level of DPPH (1,1-diphenyl-2-picrylhydrazyl) and that of hydroxyl radicals in H. kozhantschikovi extracts were 60.0% and 43.7%, respectively. The ferrous iron chelating level was 37.5% compared to the chelating value of EDTA (ethylenediaminetetraacetic acid) as a positive control at the same concentration. To verify inhibitory effects of oxidative cell damage induced by reactive oxygen species (ROS), the relative level of lipid peroxidation and the expression level of the p21 protein were compared in extracts-treated and untreated groups. Lipid peroxidation was completely inhibited in the extracts-treated group compared with the radical-only treated group. The level of p21 protein expression was restored to 92.2% of p21 protein expression in the control sample. In addition, DNA cleavage inhibition in the H. kozhantschikovi extracts was 74.1% compared with that of the control group, suggesting that H. kozhantschikovi extracts repress DNA cleavage induced by ROS. Moreover, the phosphorylation ratio of the H2AX protein was 16.7% in the radical-treated group, indicating that the ethanol extracts inhibited 83.3% of DNA damage. Our findings suggest that ethanol extracts from H. kozhantschikovi are effective not only in repressing the oxidation of free radicals and highly toxic hydroxyl radicals, but also in decreasing cell and DNA damage caused by oxidative stress.

Antioxidant Activity of the Ethanol Extract from Cooking Drips of Thunnus thynnus by Gamma Irradiation (참치 자숙액의 항산화 활성에 감마선 조사가 미치는 영향)

  • Lee, Hee-Sub;Kim, Hyun-Joo;Choi, Jong-Il;Kim, Jae-Hun;Kim, Jin-Gyu;Chun, Byung-Soo;Ahn, Dong-Hyun;Chung, Young-Jin;Kim, Yeung-Ji;Byun, Myung-Woo;Lee, Ju-Woon
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.37 no.6
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    • pp.810-814
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    • 2008
  • This study was conducted to examine the effect of a gamma irradiation on the antioxidant activity of ethanol extract from cooking drips of Thunnus thynnus (ECT). The electron donating ability against 1,1-diphenyl- 2-picryl-hydrazyl (DPPH), authentic hydroxyl radical scavenging activity by Ultra Weak Luminescence Analyzer, oxidative protection factors by Racimat method, ferric reducing antioxidant power (FRAP), and ${\beta}$-carotene bleaching activity were measured as indices of antioxidant activity. All of the results shown that irradiation increased the antioxidant activity of ECT. These results suggested that ECT could be used as an antioxidative component in food and gamma irradiation could enhance these antioxidative properties.

Antioxidant activities and quality characteristics of Yanggeng added with aged black chestnut inner shell (숙성 흑율피 첨가 양갱의 품질 특성 및 항산화성)

  • Lee, Seok Ryong;Lim, Jun Young;Kim, Mee Ree
    • Food Science and Preservation
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    • v.24 no.2
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    • pp.303-311
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    • 2017
  • This study was performed to evaluate the quality characteristics and the antioxidant activities of yanggeng added with the aged black chestnut inner shells (ACI). The levels of ACI addition to Yanggeng were 0%, 1%, 3%, or 5%. The moisture content and the reducing sugar contents of Yanggeng increased with the amount of ACI. The pH of Yanggeng with ACI decreased with the amount of ACI, but the acidity increased. Depending on the amount of ACI added, the lightness (L) and yellowness (b) values of Yanggeng with ACI decreased in the Hunter color system, and the redness (a) value increased. Textural properties by TPA showed that hardness, springiness and chewiness decreased as increase in the amount of ACI added. Total phenol content in the Yanggeng added with ACI increased with the amount of ACI added. Increasing amount of ACI addition enhanced antioxidant activities of Yanggeng, as evidenced by DPPH radical scavenging activity and hydroxyl radical scavenging activity assays. In the preference test, Yanggeng added with 3% ACI showed the highest overall preference and texture. Based on these results, when 3% ACI was added to Yanggeng the quality characteristics, antioxidant property and sensory properties were excellent.