• Title/Summary/Keyword: Acid and Alkali

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Compostion of Constituents of Commercial Wood Vinegar Liquor in Korea (시판 목초액의 성분조성)

  • Kim, Sam-Kon;Kim, Kun-Soo;Lee, Yun-Hwan;Kim, Young-Hoi
    • Applied Biological Chemistry
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    • v.44 no.4
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    • pp.262-268
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    • 2001
  • Two commercial wood vinegar liquors prepared from Cryptomeria japonica and Quercus sp., which are used as a mineral fertilizer in Korea, were extracted using dichloromethane as a solvent, respectively. The extracts were separated into acidic, phenolic, neutral and basic fraction by acid or alkali treatment, and the compositions of each fraction were analyzed by means of GC and GC-MS. A total of 103 compounds including 26 acids, 32 phenols and 45 neutral compounds were identified. The major components were acetic, propionic and n-butyric acid, representing of $41{\sim}58%$ of the acidic fraction, guaiacol, 4-methylguaiacol and phenol, repersenting of $53.2{\sim}63.9%$ of the phenolic fraction, and furfural, 3-methyl-2-cyclopenten-2-one, 2,3-dimethyl-2-cyclopenten-1-one and 5-methyl-2-furfural in the neutral fraction. In addition to these compounds, phenolic fraction in dichloromathane extract from wood vinegar liquor of C. japonica included large amounts of vanillin, acetovanillone and tentatively identified ethylvanillyl ether while that of Quercus sp. included some amounts of syringol and 4-methylsyringol.

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Postharvest Changes in Quality and Biochemical Components of Leaf Lettuce (상치의 수확후(收穫後) 품질(品質) 및 성분변화(成分變化))

  • Kim, Seong Yeol;Hong, Young Pyo;Choi, Woo Young
    • Korean Journal of Agricultural Science
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    • v.12 no.1
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    • pp.128-138
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    • 1985
  • This study was conducted to elucidate the shelf-life and quality changes in relation to biochemical components in leaf lettuce (Lactuca sativa L.). The shelf-life of leaf lettuce at room temperature was 2 to 3 days. But it was extended to 3 weeks by packaging in a 0.01 mm thick polyethylene film sack when stored at $3^{\circ}C$. The ascorbic acid contents of fresh leaf lettuce was 25 mg per 100 gram fresh weight. The acid at room temperature was almost destroyed after 4 days storage. But the contents of ascorbic acid at $3^{\circ}C$ maintained about 50 to 60% of the initial level in packaging of polyethylene film sack after 8 days storage. The content of chlorophyll was greatly decreased at room temperature but no significant changes were found at $3^{\circ}C$. The changes of total sugar and reducing sugar contents during storage were not very different between treatments. The contents of alkali soluble protein and free amino acid gradually increased in the treatments of polyethylene film sack packaging during storage in general, but the contents decreased after the increase in control treatment. Nucleic acid content, peroxidase and polyphenoloxidase activities were measured and discussed in relation to the leaf senescence.

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Physicochemical Properties and Intestinal Bacterial Growth-Promoting Effect of Cell-Wall Polysaccharides from Cucumber Peel

  • Jun, Hyun-Il;Song, Geun-Seoup;Lee, Young-Tack;Kim, Young-Soo
    • Food Science and Biotechnology
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    • v.14 no.3
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    • pp.375-379
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    • 2005
  • Physicochemical properties, intestinal microbial growth, and inhibitory effects of alcohol-insoluble polysaccharide (AIP) extracted from cucumber peel were investigated. AIP was composed of 14.54% crude protein, 1.04% crude lipid, 13.74 % crude ash, 9.1% soluble dietary fiber, and 41.2% insoluble dietary fiber. AIP showed low bulk density (0.18 g/mL) and water-holding capacity (6.39 g/g), and high oil-holding capacity (3.96 g/g). Pectic substance fractions [water-soluble pectic substance (WSP), ethylenediaminetetraacetic acid-soluble pectic substance (ESP), and alkali-soluble pectic substances (ASP)] and hemicellulose fractions [1 M KOH-soluble hemicellulose (KHP1) and 4 M KOH-soluble hemicellulose (KHP4)] were obtained from sequential chemical fractionation of AIP. WSP showed higher total sugar contents than total uronic acid contents, whereas opposite results were observed in ESP and ASP. Molecular weight distributions of three pectic substance fractions were in order of ASP>ESP>WSP. Ion exchange chromatogram pattern of WSP was different from those of ESP and ASP. Major component of WSP was fraction eluted by 0.05 M ammonium acetate buffer, whereas that of ESP and ASP was fraction eluted by 0.2 M NaOH. WSP and ASP showed growth-promoting activities against Lactobacillus brevis, Bifidobacterium bifidum, and B. longum, whereas B. bifidum and B. longum for ESP. KHP1 and KHP4 fractions had significant growth-promoting activities against B. bifidum.

The Pretreatment Effects on Methane Fermentation of Microalgal Biomass (미세조류의 전처리에 따른 메탄발효 특성)

  • Kang, Chang-min
    • Journal of Korean Society of Environmental Engineers
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    • v.22 no.5
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    • pp.849-859
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    • 2000
  • This study was conducted to identify the characteristics of methane fermentation and lysis effects of pre-treated microalgae. Chemical compositions of microalgae showed that the VS(volatile solid) was 86.1% of TS(total solid), and the protein was 63.5% of VS. These values were higher than those of activated sludge. The cell lysis test of raw microalgae biomass was conducted by many physicochemical methods. presenting that the degree of cell lysis was affected by following order: ultrasonic(100min.), alkali(pH 13), ultrasonic(10min), thermal($120^{\circ}C$), thermal($50^{\circ}C$), and acidic(pH 3) treatment. Methane fermentation with many pre-treated samples was performed, showing that the concentration of acetic acid was the highest. followed by propionic acid, butylic acid and valerie acid among all VFA(volatile fattic acid). In methane production. ultrasonic samples were only more effective than untreated one in total gas and methane productivity. but other samples were less effective. Especially. the alkalic sample had an inhibitation effect on methanogens.

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Flexible membranes with a hierarchical nanofiber/microsphere structure for oil adsorption and oil/water separation

  • Gao, Jiefeng;Li, Bei;Wang, Ling;Huang, Xuewu;Xue, Huaiguo
    • Journal of Industrial and Engineering Chemistry
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    • v.68
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    • pp.416-424
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    • 2018
  • Oil spill and oily wastewater have now become a serious threat to the freshwater and marine environments. Porous materials with super-hydrophobicity and super-oleophilicity are good candidates for the oil adsorption and oil/water separation. Here, flexible hybrid nanofibrous membrane (FHNM) containing $SiO_2$/polyvinylidene fluoride (PVDF) microspheres was prepared by simultaneous electrospinning and electrospraying. The obtained FHNM combined the flexibility of the nanofiber mat and super-hydrophobicity of the microspheres, which could not be achieved by either only electrospinning or only electrospraying. It was found that when the weight ratio between the $SiO_2$ and PVDF reached a critical value, the $SiO_2$ nanoparticles were present on the PVDF microsphere surface, significantly improving the surface roughness and hence the contact angle of the FHNM. Compared with the pure electrospun PVDF nanofiber mat, most of the FHNMs have a higher oil adsorption capacity. The FHNM could separate the oil with water quickly under the gravity and displayed a high efficiency and good reusability for the oil/water separation. More importantly, the FHNM could not only separate the oil with the pure water but also the corrosive solution including the salt, acid and alkali solution.

Surimi Processing Using Acid and Alkali Solubilization of Fish Muscle Protein (산과 알칼리 pH에서 어육 단백질의 용해를 이용한 수리미 제조)

  • 박주동;정춘희;김진수;조득문;조민성;최영준
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.32 no.3
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    • pp.400-405
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    • 2003
  • The surimi processing from jack mackerel and white croaker muscle using acidic and alkaline solubilization was evaluated. The optimum pH for solubilizing protein in acidic and alkaline range was around 2.5 and 10.5, respectively. The optimum pH value for recovery of protein was around 5. The protein solubility was decreased with increase of salt. The homogenized speed and time for maximum solubility were below 9,500 rpm and 30s, respectively The optimum ratio of water to minced muscle was 6 by evaluating breaking force, deformation and whiteness of cooked gel. The protein yield of alkaline processing is higher than that of conventional processing. In addition, the waste water of conventional processing had high solid, nitrogen content and chemical oxygen demand compare to those of acidic and alkaline processing.

Synthesis of Azo based Disperse Dyes for Dyeing Polyester Fiber in Supercritical Carbon Dioxide (초임계 유체 염색용 아조계 분산염료 합성 및 PET 섬유에 대한 염색 특성 연구)

  • Shin, Seung-Rim;An, Kyoung-Lyong;Lee, Sunhye;Lee, Seung Eun;Ko, Eunhee;Kim, Changil;Jun, Kun
    • Textile Coloration and Finishing
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    • v.31 no.3
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    • pp.135-146
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    • 2019
  • A series of azo based disperse dyes were synthesized and applied to polyester(PET) fiber in supercritical carbon dioxide($ScCO_2$). Various aniline derivatives were used as diazo component and coupled with glycine ethylester or carbonic acid ethylester derivatives to give azo based disperse dyes. Depending on the various diazo substituents, absorption maxima varied from 415 to 529nm in acetone. Dyeing in $ScCO_2$ was carried out at $120^{\circ}C$ and 250bar pressure for 2hrs with 0.5% o.w.f. of dye concentration. Dyed PET fiber had excellent brightness and good light, washing and perspiration(acid/alkali) fastness properties.

Neem (Azadirachta indica) Seed Cake in Animal Feeding-Scope and Limitations - Review -

  • Gowda, S.K.;Sastry, V.R.B.
    • Asian-Australasian Journal of Animal Sciences
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    • v.13 no.5
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    • pp.720-728
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    • 2000
  • The different products of neem (Azadirachta indica) are utilized for variety of purposes in industry, health and animal agriculture in the Indian subcontinent. The cake from seeds after oil extraction is a good source of nutrients (CP: 35-38%; EE: 4.5-5.5%; CF: 12-15%; Ca: 0.75%; P: 0.45% on DM), and in particular, the one out of its kernel is proteinaceous and is relatively balanced in its amino acid and mineral profile. But the cake is toxic and bitter to taste owing to triterpenoids (nimbin, salannin, azadirachtin), which restricts its safe inclusion in livestock diet. Several feeding trials with raw cake have revealed poor palatability and adverse performance among different categories of livestock and poultry. Internal organ changes included histological alteration in intestine, liver, kidney and distruption of spermatogenesis and ovarian activity. Ruminants appears to tolerate reasonably higher levels of the cake and to a limited low levels of dietary inclusion also proved to be tolerable in monogastric farm animals. Debitterization through solvent (hexane, ether) extraction, water washing, alkali (NaOH, 1.5, 2.5 or 3%, wt/wt) soaking and urea (1.5 or 3%, wt/wt) - ammoniation have been tried with appreciable success in improving the palatability and nutritive value of the cake. For enhanced utilization, decortication of neem seeds is to be done effectively at industrial level with maximum oil recovery. The resultant proteinaceous kernel by-product could be a cheaper unconventional protein supplement after suitable processing.

Effect of the Dye Bath and Mordants on the Dyeing of Silk Fabric using Cochineal (견섬유의 코치닐 염색에서 염욕의 액성의 매염제가 미치는 영향)

  • Kim Kyung-Sun;Jeon Dong-Won;Kim Jong-Jun
    • Journal of the Korean Home Economics Association
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    • v.43 no.7 s.209
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    • pp.109-116
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    • 2005
  • Using buffer solutions, consisting of pH 4, 5, 6, 7, and 8, silk fiber fabric specimens, pre-mordanted with one of the mordanting agents, Sn, Al, Cu, Cr, and Fe, were dyed using cochineal dyestuff. The color of the dyed silk fabric specimens was predominantly red(R) for the acidic range of pH 4 and 5, and predominantly purple(RP) for the neutral range of pH 6,7, with 8, with the pH boundary differentiating between the shades being between pH 5 and 6. As a general trend, the chroma value decreased as the pH changed from acid to alkali, and the highest chroma value us attained between pH 4 and 5. Regardless of the mordanting conditions, the trend was that $ {\Delta}E$ showed the highest measured value in the acidic range of pH 4 and 5, and it dropped abruptly after the pH 6.

The study of Phellodendron amurense Rupr. Dyeing (황벽의 염색성에 관한연구)

  • 소황옥
    • Journal of the Korean Society of Costume
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    • v.27
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    • pp.121-132
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    • 1996
  • This study showed the proper pigment extract in the Phe. Dyeing which is the basic dye of the natural plants dyeing,. Also it compared and examined the K/S the promotion of the color fastness and the effect of color difference change were attended by mordants and method of mordanting. 1. The most absorbance of Phellodendron. sol-ution is 330nm berberine is 430nm. 2. The best and proper temperature to extrat Phe,. was 80 and dyeing solution for 24 hours. 3. The pH effect was stable in the absorbances and color differences change. 4. Mordanted group increased the absorbances compared to non-mordanted sample. In case depth the most absorbance of Al. Sn. K. Cu and C. A solution were in 3% Fe and Cr were in 5%. In the color difference change they became dark reduced greenish and increased yellowish when their absorbances were in 3% 5. K./S was recoginzed by tainnin and fe, K/S was more increased pre-mordants than post-mordants. 6. Fe is the unchangable mordant in the color difference change and pre-mordants is more stable than post-mordants in the difference color. 7. Generally light C. F indicated more than grade 2 and light C. F, was much improved in post-mordanted by alumium potassium potass-ium dichromate. Washing C.F was improved in mordanted by tainnin and ferrous suulfate mordanted group was better than non-mordanted sample. Perspir-ation C,F was more stable in acid than alkali. Dry cleaning C.F indicated more than grade. 4.

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