• Nutrition Research and Practice
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• v.1 no.4
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• pp.260-265
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• 2007

Preservation methods on the physiological and brewing technical characters in bottom and top brewing yeast strains were investigated. The preserved yeasts were reactivated after 24 months storage and grown up to stationary phase. The samples of filter paper storage indicated a higher cell growth and viability during propagation than those of nitrogen and lyophilization storage independent on propagation temperature. In addition, the filter paper storage demonstrated a faster absorption of free amino nitrogen and a highest level of higher aliphatic alcohols production during propagation than other preservation methods, which can be attributed to intensive cell growth during propagation. Moreover, the filter paper storage showed a faster accumulation for glycogen and trehalose during propagation, whereas, in particular, lyophilization storage noted a longer adaptation time regarding synthesis of glycogen and trehalose with delayed cell growth. In beer analysis, the filter paper storage formed an increased higher aliphatic alcohols than control. In conclusion, the preservation of filter paper affected positively on yeast growth, viability and beer quality independent on propagation temperature. In addition, in this study, it was obtained that the HICF and Helm-test can be involved as rapid methods for determination of flocculation capacity.

• Macromolecular Research
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• v.14 no.1
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• pp.94-100
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• 2006

Although the peripheral nerve system has a relatively good regenerating capacity compared to the central nerve system, peripheral nerve repair remains a clinical challenge as restoration of normal nerve function is highly variable. Synthetic tubular nerve conduits were designed as an alternative repair method in order to replace the need for an isograft. These nerve conduits guide regenerating axons from the proximal toward the distal end, maintain within growth-promoting molecules released by the nerve stumps, and protect regenerating axons from infiltrating scar tissue. In this work, we prepared cinnamoylated alginate (CA)-collagen-chitosan nerve conduit using the lyophilization method to generate a controllable parallel channel in the center and then investigated its influence on peripheral nerve regeneration in an animal study. At 12 weeks after implantation, histological study showed that tissue cable was continuously bridging the gap of the sciatic nerve in all rats. Our newly developed nerve conduit is a promising tool for use in peripheral nerve regeneration and provides a suitable experimental model for future clinical application.

• Applied Biological Chemistry
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• v.37 no.5
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• pp.343-348
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• 1994

Ti plasmid of A. tumefaciens was labeled with $^3H-thymidine$, purified and encapsulated into phosphatidylserine (PS) and PS-cholesterol (Chol; 1 : 1 molar ratio) liposomes by lyophilization-rehydration method. PS was supplemented with 1 mole percent octadecyl rhodamine B for fluorometric measurement of PS. Liposomes entrapping $^3H-Ti plasmid$ were fused with Nicotiana sanderae protoplasts by treating with 5 mM $CaCl_2$ and 10% PEG. The fusion was evidenced by fluorescence microscopic technique. The amounts of Ti plasmid and PS associated with protoplasts were assayed by the radioactivity of $^3H-Ti plasmid$ and by the fluorescence of rhodamine B. About 7.9% of the PS liposome and 7.2% of PS-Chol liposome were fused with protoplasts. During the fusion process, about 30% of the liposomal contents of PS-Chol liposome was leaked, in contrast to about 60% leakage of its contents in PS liposome. Accounting the number of liposomes fused with protoplasts together with the encapsulation efficiency and the leakage of liposomal contents, it was calculated that ca. 1,700 Ti plasmid was transfered into one protoplast by the present method. This result may indicates that the present method transfers enough Ti plasmid into plant protoplast to elicit genetic transformation of plants.

• Journal of the Korean Chemical Society
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• v.7 no.2
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• pp.140-143
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• 1963

${\alpha}$-Ethyl-4,6-diiodo-2,3-dehydro-2,3,4,6-tetradeoxy-D-glucoside was synthesized from glucose through a modified Fischer et al. method. The yield of reduction process of an intermediate triacetylglucal, was markedly increased by utilizing lyophilization technique for removing the water in the reaction product.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.11
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• pp.249-254
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• 1997

ABA-type block copolymers composed of poly(L-leucine)(PLL) as the A component and poly(ethylene glycol)(PEG) as the B component were synthesized by ring-opening polymerization of L-leucine N-carboxyanhydride initiated by primary amino group located at both ends of PEG chain. A silver sulfadiazine(AgSD)-impregnated wound dressing of sponge-type was prepared by the lyophilization method. Morphological structure of this wound dressing obtained by scanning electron microscopy(SEM) was composed of a dense skin layer and a macroporous inner sponge layer. Equilibrium water content(EWC) of wound dressing was above 10%. It increased with an increased of PEO content in the block copolymer due to the hydrophilicity of PEO. AgSD release from AgSD- impregnated wound dressing in PBS buffer(pH=7.4) was dependent on PEG composition in the block copolymer. Therefore, EWC and release of AgSD can be control by PEG composition. Antibacterial capacity of AgSD-impregnated wound dressing was examined in agar plate against Pseudmonas aeruginosa and Stapplococus aruous. Cytotoxicity of the wound dressing was evaluated by studing mouse skin fibroblast(L929). From the behavior of antimicrobial releasing and the investigation of the suppression of bacterial proliferation, it was supposed that the wound dressing containing antibiotics could protect the wound surfaces from bacterial invasion to suppress the bacterial proliferation effectively. In cytotoxicity observation, cellular damage was reduced by the control led released of AgSD from the LEL sponge matrix of AgSD-medicated wound dressing. In vivo test, granulous tissue formation and wound contraction or the AgSD and DHEA impregnated wound dressing were aster than any other groups.

• KSBB Journal
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• v.30 no.3
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• pp.109-113
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• 2015

Current drying and encapsulation methods for probiotics manufacturing are complicate and cost-burdened processes. The aim of this study was to develop a simple ingredient mixture to make probiotic granules via one-step process, providing not only a cryoprotective effect during freezing and drying but also high survival ratio in gastrointestinal tract. As cryoprotectans, commercially available ingredients including skim milk, monosaccharide (trehalose or glycerin), maltodextrins (with low or high degree of equivalents) were used. Their cryoprotective effect during lyophilization and survival ratios in artificial gastric juice and bile salt were measured against 3 strains of lactic acid bacteria (LAB) (Lactobacillus plantarum, Lb. brevis, and Lactococcus lactis). As results, 3 mixtures with different compositions showed a cryprotective effect on LAB tested and the best compostion was dependant upon LAB; skim milk 10%, trehalose 15%, glycerin 0.5%, and NaCl 1% was for Lb. plantarum and Lc. lactis, and maltodextrin 10% instead of skim milk was for Lb. brevis. In addition, those mixtures showed similar survival effect on LAB tested. These results demonstrate that skim milk or maltodextrins with trehalose, glycerin, and NACl can be effectively used for onestep lyophilization of LAB as an alternative method of encapsulation.

• 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.

• KSBB Journal
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• v.17 no.1
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• pp.106-109
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• 2002

Gel electrophoresis of DNA is a well known technique in molecular biology. This technique is simple, rapid to perform, and capable of adequately separating fragments of DNA. A number of mixtures of DNA fragments ("DNA size markers") are frequently employed in a purpose of extrapolating the sizes or the amount of DNA molecules during gel electrophoresis. DNA size markers are constructed by digesting plasmid DNA, bacteriophage DNA, or recombinant DNA molecules with one or more restriction enzymes. However, liquid suspension containing DNA size marker needs to be kept at a low temperature during storage and shipping. In an attempt to maintain the DNA samples at room temperature for extended period of time, lyophilization of DNA with addition of nuclease inhibitor was studied. Gel loading buffer was also added to the lyophilized DNA to provide additional convenience such that DNA size marker was the "ready-to-use" followed by simply reconstituting with distilled water.

• Mycobiology
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• v.38 no.1
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• pp.33-38
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• 2010

We have successfully applied the nested PCR to detect Cylindrocarpon destructans, a major pathogen causing root rot disease from ginseng seedlings in our former study. The PCR assay, in this study, was used to detect the pathogen from soils. The nested PCR using internal transcribed spacer (ITS) 1, 4 primer set and Dest 1, 4 primer set maintained the specificity in soils containing various microorganisms. For a soil DNA extraction method targeting chlamydospores, when several cell wall disrupting methods were tested, the combination of lyophilization and grinding with glass beads, which broke almost all the chlamydospores, was the strongest. The DNA extraction method which was completed based on the above was simple and time-saving because of exclusion of unnecessary stages, and efficient to apply in soils. As three ginseng fields whose histories were known were analyzed, the PCR assay resulted as our expectation derived from the field information. The direct PCR method will be utilized as a reliable and rapid tool for detecting and monitoring C. destructans in ginseng fields.

• Journal of Veterinary Science
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• v.24 no.6
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• pp.79.1-79.16
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• 2023

Background: The need for a storage method capable of preserving the intrinsic properties of bones without using toxic substances has always been raised. Supercooling is a relatively recently introduced preservation method that meets this need. Supercooling refers to the phenomenon of liquid in which the temperature drops below its freezing point without solidifying or crystallizing. Objectives: The purpose of this study was to identify the preservation efficiency and applicability of the supercooling technique as a cortical bone allograft storage modality. Methods: The biomechanical effects of various storage methods, including deep freezing, cryopreservation, lyophilization, glycerol preservation, and supercooling, were evaluated with the three-point banding test, axial compression test, and electron microscopy. Additionally, cortical bone allografts were applied to the radial bone defect in New Zealand White rabbits to determine the biological effects. The degree of bone union was assessed with postoperative clinical signs, radiography, micro-computed tomography, and biomechanical analysis. Results: The biomechanical properties of cortical bone grafts preserved using glycerol and supercooling method were found to be comparable to those of normal bone while also significantly stronger than deep-frozen, cryopreserved, and lyophilized bone grafts. Preclinical research performed in rabbit radial defect models revealed that supercooled and glycerol-preserved bone allografts exhibited significantly better bone union than other groups. Conclusions: Considering the biomechanical and biological superiority, the supercooling technique could be one of the optimal preservation methods for cortical bone allografts. This study will form the basis for a novel application of supercooling as a bone material preservation technique.