• Title/Summary/Keyword: lyophilization

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Properties of Dextransucrase from Leuconostoc mesenteroides Isolated from Sikhae

  • Rhee, Suk-Hyung;Lee, Cheal-Ho
    • Journal of Microbiology and Biotechnology
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    • v.1 no.3
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    • pp.176-181
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    • 1991
  • Studies on the optimum conditions for dextran production and the properties of dextransucrase (DS) were performed with Leuconostoc mesenteroides from Sikhae and Leuconostoc mesenteroides NRRL B-512(F). Dextransucrases were partially purified by lyophilization of the culture supernatant and subsequent gel chromatography on Bio-Gel A-5(m). The storage stabilities of Sikhae DS and B-512(F) DS were decreaed by the addition of dextranase. The optimum conditions for the enzyme stability were pH 5 and below $30^{\circ}C$. The B-512(F) DS lost the activity at pH 4, while Sikhae DS had 30% of the activity at the same pH. The activity of DS was decreased by EDTA. confirming the metalloprotein character of the enzymes, and was restored by the addition of calcium ions. Concanavalin A completely removed the activity of DSs, confirming the glycoprotein character of the enzymes.

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Probiotic Properties of Lactobacillus salivarius Isolated from Chicken Intestines (병아리의 장에서 분리한 Lactobacillus salivarius의 생균제로서 특성)

  • 박홍식;이지혜;엄태붕
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.28 no.5
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    • pp.1003-1009
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    • 1999
  • For the isolation of probiotics which may be used for the human beings and animals, we have screened the microorganisms from chicken intestines which have acid and bile tolerance and the growth inhibition of pathogenic E. coli and Salmonella typhimurium. Among them, a strain which was identified as Lactobacillus salivarius had around 66% of survival after 2h incubation in the artificial gastric juice and 9% of survival after 24h incubation in the presence of 0.3% bile salts, and showed complete inhibition against both path ogenic E. coli and Salmonella typhimurium after 24 h coincubation. Its storage stability after lyophilization could be improved by adding polyvinylpyrrolidone.

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A Study on the Dyeing of Silk Fabrics with Chelidonium Majus Extracts (애기똥풀 추출액을 이용한 견직물 염색)

  • 최경은;이전숙;강성일
    • Journal of the Korean Home Economics Association
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    • v.42 no.7
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    • pp.55-61
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    • 2004
  • The Purpose or this study was to determine the optimal dyeing condition or Chelidonium majus extracts onto silk fabrics. Among the various dyeing properties, the colorfastness of fabrics dyed with Chelidonium majus extracts was investigated in different conditions such as dyeing temperature, dyeing time, dyeing pH etc. We also tried to dye fabrics using the Chelidonium majus extracts which were lyophilized. Although mordant was not used, dyed fabrics showed relatively good dyeability and the main pigment of Chelidonium majus showed yellow vividly in the appropriate dyeing conditions. At a dyeing temperature above 40$^{\circ}C$, the $\Delta$E value increased but the yellowish tint decreased. The pH value of unadjusted Chelidonium majus extracts was 6.4, at which a deep yellow was obtained. The dye equilibrium was reached 40 minutes after dyeing. The colorfastness to washing and light was poor at 1-2 and 2-3, respectively, but the dry-cleaning fastness was good at 4-5.

Enhancement in the Viability and Biosensing activity of Freeze-Dried Recombinant Bioluminescent Bacteria

  • Park, Sue-Hyung;Gu, Man-Bock
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.5 no.3
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    • pp.202-206
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    • 2000
  • The genetically-engineered Escherichia coli strain, DPD2540, which contains a fabA:::luxCDAbefusion gene, gives a bioluminescent output when membrane fatty acid synthesis is needed. For more pactical application of this strain in the filed as biosensor, freezedrying was adopted. A 12% surcrose solution with Luria-Bertani (LB) broth, as determined by the viability after freeze-drying, was found to be most most effective composition for lyophilization solution among various compositions testitons tested. Rapid freezing with liquid nitrogen also gave the best viability after freeze-drying as compared to samples frozen at-7$0^{\circ}C$ and -2$0^{\circ}C$. The biosensing activities of the cells showed a greater sensitivity when the cells from the expontial phase were freeze-dried. Finally, the optimum temperature for use of the freeze-dried cells in the biodencor field was determined.

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Effects of Crataegii Fructus on the Diet-induced Hyperlipidemia in Rats (산사(山揸)가 흰쥐의 식이성 고지혈증(高脂血症)에 미치는 영향)

  • Kwon, Soon-Hyuk;Kim, Jeung-Beum
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.24 no.1
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    • pp.67-73
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    • 2010
  • The purpose of this study was to investigate the effects of Crataegii Fructus on the diet-induced hyperlipidemia in rats. Rats were divided into 4 groups, normal group(supplied enough water and feeds only), high fat diet administered group(supplied high fat diet for 4 weeks, Control group) and Crataegii Fructus administered group(supplied high fat diet and Crataegii Fructus lyophilization extract for 4 weeks, 397.3 mg/kg(rat) in sample A, 662.5 mg/kg(rat) in sample B). Body weight, liver weight and serum lipid levels were evaluated. The water extract of Crataegii Fructus decreased liver weight and triglyceride in high fat diet induced hyperlipidemia in rats, and increased HDL-cholesterol.

Effects of Polygonati Rhizoma on the Diet-induced Hyperlipidemia in Rats (황정(黃精)이 흰쥐의 식이성 고지혈증에 미치는 영향)

  • Roh, Seung-Won;Kim, Jeong-Beom
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.22 no.5
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    • pp.1147-1151
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    • 2008
  • The purpose of this study was to investigate the effects of Polygonati Rhizoma on the diet-induced hyperlipidemia in rats. Rats were divided into 4 groups, normal group(supplied enough water and feeds only), high fat diet administered group(supplied high fat diet for 4 weeks, Control group) and Astragali Radix administered group(supplied high fat diet and Astragali Radix lyophilization extract for 4 weeks, 397.3 mg/kg(rat) in sample A, 662.5mg/kg(rat) in sample B). Body weight, liver weight and serum lipid levels were evaluated. The water extract of Polygonati Rhizoma decreased body weight, liver weight, total cholesterol, LDL-cholesterol, triglyceride and phospolipid in high fat diet induced hyperlipidemia in rats, and increased HDL-cholesterol.

Effects of Astragali Radix on the Diet-induced Hyperlipidemia in Rats (황기가 흰쥐의 식이성 고지혈증에 미치는 영향)

  • Kim, Hak-Joon;Kim, Jeung-Beum
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.22 no.3
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    • pp.575-579
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    • 2008
  • The purpose of this study was to investigate the effects of Astragali Radix on the diet-induced hyperlipidemia in rats. Hyperlipedemia was induced in rats with high fat diet. Rats were divided into 4 groups, normal group(supplied enough water and feeds only), high fat diet administered group(supplied high fat diet for 4 weeks, Control group) and Astragali Radix administered group(supplied high fat diet and Astragali Radix lyophilization extract for 4 weeks, 178.6 mg/kg(rat) in sample A, 297.8 mg/kg(rat) in sample B). Body weight, liver weight and serum lipid levels were evaluated. The water extract of Astragali Radix decreased body weight, liver weight, total cholesterol, LDL-cholesterol, triglyceride and phospolipid in high fat diet induced hyperlipidemia in rats, and increased HDL-cholesterol.

Preparation of Blood Glue from Porcine Plasma Protein and Cross-linking Reaction of Plasma Protein with Formaldehyde

  • Cho, Yongsik;Lee, Hwahyoung;Song, Kyung Bin
    • Journal of Applied Biological Chemistry
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    • v.42 no.2
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    • pp.81-84
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    • 1999
  • Blood glue was prepared to reutilize porcine blood. Plasma proteins after lyophilization were treated by addition of wood flour, sodium hydroxide, sodium silicate, and hydrated lime to make blood glue with a suitable adhesivity. Characteristics of the prepared blood glue was monitored by measuring the viscosity with time, and the relationship between degree of hydrolysis of plasma proteins by addition of various amounts of sodium hydroxide and adhesivity was studied. To prevent the emission of formaldehyde during manufacturing of plywood by blood glue, the cross-linking reaction of plasma protein with formaldehyde was also examined. Fourier transform infrared, circular dichroism, and fluorescence spectroscopy study showed that blood plasma proteins react with formaldehyde, resulting in removal of formaldehyde by cross-linking reaction.

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유기용매 내에서 중쇄지방질의 합성

  • Gwon, Dae-Yeong
    • Bulletin of Food Technology
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    • v.7 no.2
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    • pp.64-73
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    • 1994
  • Using 20 lipases from various microbial origins medium chain glycerides, namely, mono-, di-, and tri-carproyl glycerols from glycerol and acid were synthesized in isooctane. Enzyme reaction was performed at 0.35 M of capric acid, 0.025M of glycerol and the same mass of silica gel to remove water in 5ml of isooctane with 30mg of lyophilized lipase. Among 20 lipases, eleven lipases showed good synthetic activities, especially lipase from Pseudomonas aeruginosa (Lipase PS), Rhizomucor miehei origined lipase and Chromobacterium viscosum lipase (Lipase CV) showed good activities for production of tricaproylglycerol, while Lipase OF-360 (origined from Candida rugosa) and Lipase D (Rhizopus delemar) were good for production of dicaprolyglycerol. The lipases, especially Lipase PS, have high thermal stability at $ 60^{circ}C$, and optimum pH of lyophilization for dehydrating the lipase was pH 6.5.

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XPS STUDY ON DNA DAMAGE BY LOW-ENERGY ELECTRON IRRADIATION

  • Noh, Hyung-Ah;Cho, Hyuck
    • Journal of Radiation Protection and Research
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    • v.36 no.4
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    • pp.190-194
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    • 2011
  • After the first report that electrons with sub-ionization energy of DNA could cause single strand breaks or double strand breaks to DNA, there have been various studies to investigate the mechanisms of DNA damage by low-energy electrons. In this paper, we examined the possibility of using X-ray photoelectron spectroscopy (XPS) to analyze the dissociation patterns of the molecular bonds by electron irradiation on DNA thin films and tried to establish the method as a general tool for studying the radiation damage of biomolecules by low energ yelectrons. For the experiment, pBR322 plasmid DNA solution was formed into the films on tantalum plates by lyophilization and was irradiated by 5-eV electrons. Un-irradiated and irradiated DNA films were compared and analyzed using the XPS technique.