• Journal of Life Science
• /
• v.22 no.12
• /
• pp.1665-1671
• /
• 2012

This study was conducted to assess the removal of residual pesticides and to obtain high amounts of quercetin in onion peel extracts (OPEs) by 4 washing treatments. Washing is one of the standard processing steps in obtaining functional food ingredients from onion peel. After a first detergent wash (0.2% w/v) (DW) and hot air drying ($80^{\circ}C$, 24 hr) (B), 4 washing treatments were tested, including a second DW (C), ultrasonication ($50^{\circ}C$, 10 min) plus DW (D), 0.3% $H_2O_2$ (v/v) plus DW (E), and blanching ($95-97^{\circ}C$, 2 min) plus DW (F). This was followed by 60% (v/v) ethanol extraction and vacuum freeze drying of the OPE. The E treatment yielded 89.04% OPE and a quercetin content of 96.84% in the OPE compared with the B treatment, and had the highest efficiency of all treatments tested. The OPE was tested for the presence of 177 residual pesticides and three compounds were detected in all treatments: cyhalothirn, fluquinconazole and procymidone. Cyhalothirn and fluquinconazole levels were below the permitted levels for fresh onion, while procymidone was present in the high level range of 128.01~133.46 mg/kg in all samples. The E treatment was a better washing method than the others for removal of residual pesticides. It could reduce the level of residual pesticides without changing the functional properties of the OPE.

• The Korea Journal of Herbology
• /
• v.22 no.2
• /
• pp.51-63
• /
• 2007

Objectives : For the congenital feeble, the Gongjindan is useful medicine. The experiment is to estimate the value of the Gongjindan as therapeutic agent preventing against aging with an analysis of the ingredients and the bio-activating effects by enzymologic methods. Methods : General ingredients' of the Gongjindan's extract were analyzed first and the quantitative analysis of a reducing sugar, a soluble protein, an amino acid and minerals was made. The Gongjindan, which is extracted, concentrated, and freeze drying with water, ethanol and chloroform, have got applied for the experiment. The effects on electronic donating ability, SOD-like activity, nitric oxide inhibition, xanthine oxidase inhibition, whitening effect have been investigated in the physiological activity measurement of function experiment. Results : The contained amino acid, in order of high amount, is Arginine, Alanine, Glutamic acid, Proline and the contained free amino acid is Glutamic acid, Leucine, Lysine, Phenylalanine. The derivative of free amino acid is ${\gamma}-Aminoisobutyric$ acid, Phosphoserine, Taurine. And the Gongjindan is containing 13 species of minerals in order of Ca>K>Na>Mg>Fe>AI>Mn. Then, to assure of the Gongjindan's capability of anti-oxidation, these following subjects-polyphenol, electronic donating ability, SOD-like activity, nitric oxide inhibition, xanthine oxidase inhibition, tyrosinase inhibition- are analyzed and show high activity especially the most in ethanol extracts. Conclusion : With this analysis of ingredients, the Gongjindan is containing many materials functioning as anti-oxidation, anti-aging, anti-fatigue, neurotransmitter and immune agent. Moreover, In every water, ethanol, chloroform extracts, the Gongjindan's capability of anti-oxidation is confirmed so that we can apply to patients' treatment clinically.

• YAKHAK HOEJI
• /
• v.42 no.3
• /
• pp.265-274
• /
• 1998

In order to attain a sustained release at targeted organs in a prolonged time which can reduce the side effects and maximize the therapeutic effect, aclarubicin (ACL) was entrap ped into liposomes of different lipid compositions using Microfluidizer, and dry liposomes were prepared by lyophilization. The dry aclarubicin-entrapped liposomes were evaluated in terms of mean particle size and size distribution, entrapment efficiency and in vitro drug release profile. The Entrapment efficiency of liposome, when the concentration of aclarubicin and lipid were 0.5 to 1.0mg/ml and $200{\mu}mol$/ml, respectively, was over 80% using Microfluidizer, in contrast to 70% of entrapment efficiency using hand-shaking method. Mean particle size and size distribution of aclarubicin-entrapped liposomes of various lipid compositions did not change considerably by the freeze drying. The range of particle size was between 80 and 200nm. Among aclarubicin-entrapped liposomes, ACL-liposome of PC/DPPC/CH0L/TA displayed the most significant sustained release. The addition of DPPC appeared to be favorable for the control of release. In general, aclarubicin entrapped in liposomes was less stable than free aclarubicin either in pH 7.4 phosphate buffer or in human plasma. Formulation I($t_{1/2}$, 20.3 hr) devoid of lipid additive was the most unstable in the phosphate-buffer solution while formulation II($t_{1/2}$, 40.7 hr) with cardiolipin was the most stable. Half lives of aclarubicin-entrapped liposomes in human plasma were 43.2, 50.7, 35.9 and 35.3 hr for formulation I. II, III and IV, respectively, in contrast to 57.8 hr for free aclarubicin.

• KSBB Journal
• /
• v.13 no.5
• /
• pp.502-510
• /
• 1998

Stabilization of antibody, which is specific to Salmonella typhimurium antigens, present in dry states on membranes was accomplished, and its shelf-life, i.e., duration for maintaining minimum 90% of the initial activity, under optimal conditions was determined. To prepare two major components of an immuno-strip, the antibody was not only immobilized on nitrocellulose membrane surfaces but also placed within the pores of glass fiber membrane after conjugating it with old colloids as signal generator. Among potential stabilizers of the immuno-components, a disaccharide, trehalose, showed a significant protection effect of immunoglobulin structure from thermal energy. Optimal concentrations of trehalose for the respective component were significantly different (8-fold higher for the antibody-gold conjugate than for the immobilized antibody), which probably resulted from distinct densities and configurations of antibody present on the membranes. An additional requirement for the gold conjugate was freeze-drying of this substance such that the conjugate can be readily resolubilized upon contact with aqueous medium. By using the components prepared under optimal conditions, immuno-strips were constructed and exposed to thermal energy. Signals with less than 10% decrease in the intensity were maintained for approximately 21 days at 60$^{\circ}C$. Compared to previous reports, this result represented a 2-year shelf-life at room temperature. it was, however, two times longer if determined from thermal acceleration tests based on the theory of inactivation rate of protein. Such discrepancy between the two estimates could be mainly attributed to errors in accurately controlling temperatures and also to changes in the physical properties of membranes due to a high thermal energy.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.12 no.2
• /
• pp.87-90
• /
• 2002

$LiCoO_{2}$ powders were synthesized at various temperatures using lithium hydroxide and cobalt hydroxide as precursors prepared by precipitation process and freeze-drying. In this study, the$LiCoO_{2}$ samples were synthesized via a solid state reaction with various LiOH concentration between 10 % and 30 % excess. And $LiCoO_{2}$powders were calcined at 600~$800^{\circ}C$ in a short time. Measurements of XRD and SEM were performed to characterize the properties of the prepared materials. The effect of amount of Li ions on the structural change in powder has been examined using the XRD analysis. For the not added excess of LiOH, CoOOH phase presented in the XRD pattern of $LiCoO_{2}$ due to loss of Li ions during firing. The morphology and particle size of the powders were examined using SEM. The obtained powders are high temperature-$LiCoO_{2}$HT-LiCoO$_{2}$) and homogeneous with the range of grain size in the order of hundreds of nanometers. The effects of variation of LiOH concentration on the structural change in powder were investigated using the Rietveld analysis. As an analysis result, c/a is constant by 4.99 on all occasions. Finally, the structure of HT-$LiCoO_{2}$ was simulated by the commercial software $Creius^{2}$(Molecular Simulations, Inc.) from the results of Rietveld analysis.

• Journal of Dairy Science and Biotechnology
• /
• v.36 no.3
• /
• pp.164-170
• /
• 2018

The objectives of this study were to manufacture casein phosphopeptide (CPP)/chitosan oligosaccharide (CSO) nanocomplexes and to investigate the impacts of manufacturing variables, such as CPP concentration and pH, on their morphological and physicochemical characteristics. Transmission electron microscopy (TEM) and particle size analysis were used to assess the morphological and physicochemical properties of the CPP/CSO nano-complexes, respectively. Based on the images obtained by TEM, the spherical shapes of the CPP/CSO nanocomplexes ranged from 50 to 150 nm. As the concentration of CPP was increased and the pH was decreased, the average particle size of the nanocomplexes significantly (p<0.05) increased. The CPP/CSO nanocomplexes had a highly uniform distribution with a polydispersity index value of less than 0.3. In addition, they had a negative surface charge with a zeta-potential value between -17 and -26 mV. The CPP/CSO nanocomplexes showed good stability during the freeze-drying process. In conclusion, CPP/CSO nanocomplexes were successfully manufactured, and the CPP concentration and pH were found to be key factors that affected their morphological and physicochemical properties.

• The Korean Journal of Food And Nutrition
• /
• v.25 no.4
• /
• pp.747-754
• /
• 2012

The objective of this study was to investigate free amino acid composition, antioxidant activity, alcohol dehydrogenase activity and the sensory quality attributes for the development of functional soy sauce using Hutgae (Hovenia dulcis Thunb) fruit, which is well-known for improving liver function and alleviating various negative physiological effects following heavy consumption of alcoholic beverages. Soy sauces adding six types of extract from Hutgae fruit (HF) were prepared (SSH1: HF 20%, SSH2: HF 10%, SSH3: HF 20%/40 days NaCl extract, SSH4: HF 20%/20 days NaCl extract, SSH5: HF 20% water bath extract, SSH6: freeze-drying powder from HF 20% aqueous extract), compared with soy sauce using the conventional method. These soy sauces were used for determining alcohol dehydrogenase activity by NADH absorbance, the antioxidant effect by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and sensory evaluation by sensory scaling. Total free amino acid contents for most samples were in the range of 327.3 to 375.5 mg%, and then, aspartic acid and glutamic acid content of SSH1 and SSH5 were higher than that of others. DPPH radical scavenging activity was shown to be the highest in SSH4, also SSH1, SSH5 and SSF6 were shown to be higher than the control group. Alcohol dehydrogenase activity was shown to be the highest in SSH5. In sensory evaluation, the highest intensity of roast smell was observed in SSH4 while sweet taste was shown to be the highest in SSH5, and SSH3 and SSH5 revealed higher overall acceptability. From these results, Hutgae fruit soy sauces demonstrated antioxidant activity and alcohol dehydrogenase activity. In conclusion, soy sauces containing the water bath extract of Hutgae fruit may be used as a functional seasoning.

• Membrane Journal
• /
• v.19 no.1
• /
• pp.47-53
• /
• 2009

The aim of this paper is to prepare metal/ceramic composite ultrafiltration membranes by coating inorganic particles on a metallic hollow fiber filter. The diameter and the pore size of the filter was 2.0 mm and $2{\sim}8{\mu}m$. The metal/ceramic composite ultrafiltration membranes were obtained by a coating process of silica and titania sols on top of the metallic filter. For this purpose the method of fast freeze drying and dip-coating were used. It was found that the pore size of the membrane was about 50 nm from SEM and PMI characterization. The pore size was controlled by changing the size of the particles, sintering period and temperature.

• The Korean Journal of Mycology
• /
• v.11 no.2
• /
• pp.69-77
• /
• 1983

To find antitumor components with low toxicity in the Basidiomycetes of Korea, the carpophores of Flammulina velutipes (Fr.) Singer were extracted with hot water for eight hours. The extract was purified by dialyzing through Visking tube and a protein-bound polysaccharide fraction was obtained as pale brownish amorphous powder after freeze-drying. The fraction was examined for antitumor activity against sarcoma 180 implanted subcutaneously in the left groin in ICR mice. The inhibition ratio of this fraction against the tumor was 62.3% at the dose of 10mg/kg/day for the period of ten days. The tumors in three of the ten treated mice were completely regressed. The chemical analysis of the antitumor component by anthrone and Lowry-Folin methods showed that it consisted of a polysaccharide (42.4%) and a protein (24.5%). The hydrolysis of the polysaccharide moiety with 3% HCl-MeOH and trimethysilylation of the hydrolyzate yielded five monosaccharides which were identified by G.L.C. Several amino acids were identified by an amino acid autoanalyzer in the acid hydrolyzate of the protein moiety.

• Polymer(Korea)
• /
• v.34 no.6
• /
• pp.534-539
• /
• 2010

Polystyrene (PS)/multi-walled carbon nanotube (MWCNT) nanocomposites were prepared via latex technology and the effect of nanotube length on rheological properties were investigated. Monodisperse PS particle was synthesized by the emulsifier-free emulsion polymerization and two types of MWCNTs were used after surface modification to improve dispersion state and to remove impurities. Final nanocomposites were prepared by the freeze-drying process after dispersing the PS particles and the surface-modified MWCNTs in a ultrasonic bath. The effects of MWCNT content and nanotube length on rheological properties were evaluated by imposing the small-amplitude oscillatory shear flow. The PS/MWCNT nanocomposites showed that rheological properties were enhanced as the amount and length of MWCNT increased. It is speculated that the rheological characteristics of nanocomposites change from liquid-like to solid-like as the MWCNT amount increases, and the critical concentration to achieve network structure decreases as the nanotube length increases.