• Title/Summary/Keyword: Liquid Nitrogen Storage

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A Study of Establishment and Exploitation of Bio-markers for Determination of Shelf-life of Eggs and Egg Products (알 및 알가공품의 유통기한 설정을 위한 지표개발 및 산출 연구)

  • An, Ji-Hui;Park, Jung-Min;Gu, Ja-Gyeong;Yoon, Su-Jin;Lee, Jeong-Soo;Kim, Jang-Mi;Kim, Sae-Hun;Kim, Ryong-Joo;Park, Jae-Woo;Song, Sung-Ok;Wee, Sung-Hwan;Kim, Jin-Man
    • Food Science of Animal Resources
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    • v.32 no.3
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    • pp.354-363
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    • 2012
  • The study was conducted to determine bio-markers and establish shelf-life for eggs and egg products. The selected biomarkers were measured storage period according to samples (two months for table eggs and two weeks for whole liquid eggs) and five storage temperatures ($10^{\circ}C$, $15^{\circ}C$, $25^{\circ}C$, $35^{\circ}C$ and $45^{\circ}C$). The bio-markers for table eggs determined pH, acid value, VBN (volatile basic nitrogen), HU (Haugh unit), aerobic plate counts, coliform group, and Salmonella sp. The bio-markers for whole liquid eggs excluded HU in the bio-markers of eggs. The shelf-life of table eggs observed as 42 d at $10^{\circ}C$, 27 d at $15^{\circ}C$, 9 d at $25^{\circ}C$, 2 d at $35^{\circ}C$, and 1 d at $45^{\circ}C$ in sensory overall acceptability. The shelf-life of pasteurized whole liquid eggs observed as 7 d at $10^{\circ}C$, 3 d at $15^{\circ}C$, 2 d at $25^{\circ}C$, 1 d at $35^{\circ}C$, and less than one d at $45^{\circ}C$ in total plate count. The shelf-life of non- pasteurized whole liquid eggs observed as 4 d at $10^{\circ}C$, 2 d at $15^{\circ}C$, 1 d at $25^{\circ}C$, and less than 1 d at $35^{\circ}C$ and $45^{\circ}C$ in total plate count.

A Modified Cryopreservation Method of Psychrophilic Chlorophyta Pyramimonas sp. from Antarctica

  • Hong, Sung-Soo;Lee, Soo-Young;Kim, Young-Nam;Kang, Sung-Ho;Kim, Hak-Jun
    • Ocean and Polar Research
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    • v.33 no.3
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    • pp.303-308
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    • 2011
  • Polar psychrophiles which thrive under extreme conditions such as cold temperature, high salinity, and high dose ultraviolet light, emerge as novel targets for biotechnology. To prevent genetic drift and the possibility of contamination by subculturing, cryopreservation was employed for two psychrophilic microalgae, Porosira sp. (KOPRI AnM0008) and Pyramimonas sp. (KOPRI AnM0046), which have anti-freeze activities. Five cryoprotectants (dimethyl sulphoxide, ethylene glycol, glycerol, methanol and propylene glycol) showed toxicity at 20-30% (v/v). The optimal cryoprotectant concentration and equilibration time were less than 20% and 10 min, respectively. Cryopreservation was carried out in the presence of cryoprotectants either by direct freezing in liquid nitrogen ($LN_2$) or controlled freezing using a controlled rate freezer followed by storage in the $LN_2$ tank. As a result, Pyramimonas sp. (KOPRI AnM0046), a psychrophilic chlorophyta was revived. Cryopreserved Porosira sp. was not revived from either freezing protocols probably due to the silicic cell wall and its relatively large cell size. In the case of Pyramimonas sp. (KOPRI AnM0046), the controlled freezing method showed higher revival yield than the direct freezing method.

Influence of Osmolality of Complete Semen Extender on Motion Characteristics of Frozen-thawed Ram Spermatozoa

  • Joshi, Anil;Mathur, A.K.;Naqvi, S.M.K.;Mittal, J.P.
    • Asian-Australasian Journal of Animal Sciences
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    • v.19 no.12
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    • pp.1716-1721
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    • 2006
  • The present study was conducted to observe the effect of osmolality of glycerolated TEST-yolk glycerol extenders on post-thawing sperm kinematics of ram spermatozoa of the native Malpura breed maintained in a semi-arid tropical environment. Good quality semen obtained from adult rams was pooled, split and diluted to 1,000 million spermatozoa per ml in complete TEST-yolk-glycerol extenders of 900, 1,200, 1,500 and 1,800 mOsm/kg osmolality. Diluted semen samples were loaded in 0.25 ml straws and cooled down to $-125^{\circ}C$ freezing temperature at the rate of $-25^{\circ}C$ per minute under controlled conditions before plunging into liquid nitrogen for storage. The thawing of straws was performed at $50^{\circ}C$ in a water bath for 10 seconds and sperm kinematics of the frozen-thawed spermatozoa were assessed by a computer-assisted sperm analysis technique. Osmolality of diluent had no significant effect on post-thawing % motility, % rapid, % medium and % slow moving frozen-thawed spermatozoa but significantly (p< 0.05) affected the % linearity and % straightness. The post-thawing % motility and % rapid motile spermatozoa were highest in samples extended in diluent of 1,500 mOsm/kg osmolality and lowest in 900 mOsm/kg. The curvilinear velocity of spermatozoa was significantly (p<0.05) higher for samples extended in 1,800 mOsm/kg, compared to those in 900 and 1,200 mOsm/kg, but the effect was not significantly different to those extended in diluent of 1,500 mOsm/kg osmolality. The study indicated that ram spermatozoa could tolerate a wide osmolality range for dilution in the complete TEST-yolk-glycerol extender for their cryosurvival. The highest recovery of motile spermatozoa following thawing was achieved in samples extended in the TEST-yolk-glycerol diluent of 1,500 mOsm/kg osmolality.

Effects of Electromagnetic Heating on Quick Freezing

  • Kim, Jinse;Park, Jong Woo;Park, Seokho;Choi, Dong Soo;Choi, Seung Ryul;Kim, Yong Hoon;Lee, Soo Jang;Yoo, Seon Mi;Han, Gui Jeung
    • Journal of Biosystems Engineering
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    • v.40 no.3
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    • pp.271-276
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    • 2015
  • Purpose: Quick freezing is widely used in commercial food storage. Well-known freezing techniques such as individual quick freezing require a low-temperature coolant and small cuts for the heat-transfer efficiency. However, the freezing method for bulk food resembles techniques used in the 1970s. In this study, electromagnetic (EM) heating was applied to improve the quick freezing of bulk food. Methods: During freezing, the surface of food can be rapidly cooled by an outside coolant, but the inner parts of the food cool slowly owing to the latent heat from the phase change. EM waves can directly heat the inner parts of food to prevent it from freezing until the outer parts finish their phase change and are cooled rapidly. The center temperature of garlic cloves was probed with optical thermo sensors while liquid nitrogen (LN) was sprayed. Results: When EM heating was applied, the center cooling time of the garlic cloves from freezing until $-10^{\circ}C$ was 48 s, which was approximately half the value of 85 s obtained without EM heating. For the white radish cubes, the center cooling time was also improved, from 288 to 132 s. The samples frozen by LN spray with EM heating had a closer hardness to the unfrozen samples than the samples frozen by LN only. Conclusions: The EM heating during quick freezing functions to maintain the hardness of fresh food by reducing the freezing time from 0 to $-10^{\circ}C$.

Solubility and Physicochemical Stability of Caroverine Hydrochloride in Aqueous Solution (수용액중 염산카로베린의 용해성 및 안정성)

  • Gwak, Hye-Sun;Lee, Dong-Soo;Chun, In-Koo
    • Journal of Pharmaceutical Investigation
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    • v.28 no.2
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    • pp.121-126
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    • 1998
  • The solubility and physicochemical stability of caroverine hydrochloride (CRV), an antispasmodic, in buffered aqueous solutions were studied using a reverse phase high performance liquid chromatography. The solubilty of the drug at pH 2.76-5.40 was similar at the range 31.9-36.2 mg/ml $(34^{circ}C)$, but, at the pH higher than 6.0, markedly decreased. The use of polyethylene glycol 400 as a cosolvent did not increase the solubility at any compositions examined. Moreover. increasing molar concentration of aqueous phosphate buffer from 0 to 0.5 M remarkably decreased the solubility. The degradation of CRY followed the apparent first-order kinetics. The degradation was accelerated with decreasing pH and increasing storage temperature. The half-lives for the degradation of CRY (1.0 mg/ml) at pH 1.28. 4.01 and 5.93 $(45^{\circ}C)$ were 2.8, 31.4 and 124 hr. respectively. The pHs of incubated solutions were to some extent lowered perhaps due to the formation of acidic degradation products. The addition of disodium edetate (0.01%) to the CRY solution (pH 4.95) retarded 2.5 times the degradation rate at $45^{\circ}C$, but the use of sodium bisulfite (0.1%) accelerated 2.9 times the rate. The activation energy for the CRY solution (20 mg/ml. pH 5.4) containing 0.01% EDTA was calculated to be 5.98 kcal/mole. When the solution was stored under nitrogen displacement in ampoule, there was no significant degradation even after 3 months at $40^{\circ}C$, indicating that protection from oxidation by air (oxygen) is essential for the complete stabilization of CRY solution.

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Morphological and Genetic Stability of Dormant Apple Winter Buds After Cryopreservation

  • Yi, JungYoon;Lee, GiAn;Chung, JongWook;Lee, YoungYi;Kwak, JaeGyun;Lee, SeokYoung
    • Korean Journal of Plant Resources
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    • v.28 no.6
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    • pp.697-703
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    • 2015
  • Twenty apple germplasm accessions from the Korean Genebank were successfully cryopreserved using two-step freezing to back up genetic resources maintained by field collections. This study examined the morphological and genetic stability of cryopreserved dormant apple buds that were stored in liquid nitrogen, and then rewarmed and regrown. Whole plants were regenerated directly from dormant buds through budding without an intermediary callus phase. The cryopreserved buds produced high levels of shoot formation (76.2-100%), similar to those of noncryopreserved buds (91.3-100%), with no observed differences between cryopreserved and noncryopreserved materials. Three of the twenty cryopreserved apple germplasm accessions were used to assess morphological and genetic stability. No differences in morphological characteristics including shoot length, leaf shape, leaf width/length ratio, and root length were observed between controls (fresh control and noncryopreserved) and cryopreserved plantlets. The genetic stability of regenerants (before and after cryopreservation) was investigated using inter simple sequence repeat (ISSR) markers. The ISSR markers produced 253 bands using four primers, ISSR 810, SSR 835, ISSR 864, and ISSR 899. These markers showed monomorphic banding patterns and revealed no polymorphism between the mother plant and regenerants before and after cryopreservation, suggesting that cryopreservation using two-step freezing does not affect the genetic stability of apple germplasm. These results show that two-step freezing cryopreservation is a practical method for long-term storage of apple germplasms.

Effect of green tea extract in extender of Simmental bull semen on pregnancy rate of recipients

  • Susilowati, Suherni;Sardjito, Trilas;Mustofa, Imam;Widodo, Oky Setio;Kurnijasanti, Rochmah
    • Animal Bioscience
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    • v.34 no.2
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    • pp.198-204
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    • 2021
  • Objective: The aim of this study was to ascertain the effects of adding green tea extract (GTE) to skim milk-egg yolk (SM-EY) extender on both the quality of post-thawed bull semen and the pregnancy rates of the recipient cows. Methods: Twelve ejaculates from four Simmental bulls, aged 3 to 5 years and weighing 900 to 950 kg, were diluted SM-EY extender, added with 0, 0.05, 0.1, and 0.15 mg GTE/100 mL extender and then frozen. After four weeks storage in liquid nitrogen, the sperm were thawed and evaluated for viability, motility, intact plasma membrane (IPM), and DNA fragmentation. Meanwhile, the estrus cycles of 48 recipient cows were synchronized by intramuscular administration of a single injection of 5 mg prostaglandin F2α. Estrus cows were divided into four equal groups and inseminated artificially 18 to 20 h after the onset of estrus by using semen from each extender group. Pregnancy was diagnosed by measuring serum progesterone levels at 21 days, followed by transrectal palpation 90 days after insemination. Results: The findings revealed that adding 0.1 mg of GTE/100 mL extender produced the highest percentages of sperm viability (70.67%±1.75%), motility (69.17%±1.47%), and IPM (69.23%±1.21%) and the lowest percentage of DNA fragmentation (3.00%±0.50%). The pregnancy diagnosis revealed that all cows (36/36) inseminated using frozen semen in GTE addition extender were pregnant (pregnancy rate 100%), whereas the pregnancy rate of the control group was 83.33% (10/12). Conclusion: It may be concluded that 0.1 mg GTE/100 mL extender yields the best quality of spermatozoa and that all variants doses of GTE in extender produce a higher pregnancy rate among recipient cows.

Effects of Slow Freezing on Development of Blastomeres Separated from Mouse Preimplantation Embryos (완만동결이 생쥐 초기배 난할세포의 발달에 미치는 영향)

  • Jin, D.I.
    • Korean Journal of Animal Reproduction
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    • v.24 no.3
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    • pp.263-268
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    • 2000
  • The development of single blastomeres isolated from 2-, 4- and 8-cell mouse embryos and the ability of such blastomeres to survive slow freezing were studied. Of 223, 60 and 188 single blastomeres isolated from 2-, 4- and 8-cell mouse embryos, respectively, 111 blastomeres (49.8%) from 2-cell embryos, 12 blastomeres (20.0%) from 4-cell embryos and blastomeres (16.5) from 8-cell embryos developed into blastocysts after culture for 96 hrs. The recovery rate was 54.2% (65/120), 46.4% (13/28) and 24.3% (17/70) of blastomeres derived from 2-, 4- and 8-cell embryos following freezing and thawing and the survival of frozen-thawed blastomeres was 27.1% (16/59), 36.4% (4/11) and 17.6% (3/17), and respectively. The apparently six normal fetuses were obtained from frozen-thawed blastomere from 2-cell embryos after transferring into the recipients. These results indicate that mouse btastomeres isolated from preimplatation stage embryos can survive storage in liquid nitrogen following slow freezing.

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Cryopreservation of mesenchymal stem cells derived from dental pulp: a systematic review

  • Sabrina Moreira Paes;Yasmine Mendes Pupo;Bruno Cavalini Cavenago;Thiago Fonseca-Silva;Carolina Carvalho de Oliveira Santos
    • Restorative Dentistry and Endodontics
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    • v.46 no.2
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    • pp.26.1-26.15
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    • 2021
  • Objectives: The aim of the present systematic review was to investigate the cryopreservation process of dental pulp mesenchymal stromal cells and whether cryopreservation is effective in promoting cell viability and recovery. Materials and Methods: This systematic review was developed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement and the research question was determined using the population, exposure, comparison, and outcomes strategy. Electronic searches were conducted in the PubMed, Cochrane Library, Science Direct, LILACS, and SciELO databases and in the gray literature (dissertations and thesis databases and Google Scholar) for relevant articles published up to March 2019. Clinical trial studies performed with dental pulp of human permanent or primary teeth, containing concrete information regarding the cryopreservation stages, and with cryopreservation performed for a period of at least 1 week were included in this study. Results: The search strategy resulted in the retrieval of 185 publications. After the application of the eligibility criteria, 21 articles were selected for a qualitative analysis. Conclusions: The cryopreservation process must be carried out in 6 stages: tooth disinfection, pulp extraction, cell isolation, cell proliferation, cryopreservation, and thawing. In addition, it can be inferred that the use of dimethyl sulfoxide, programmable freezing, and storage in liquid nitrogen are associated with a high rate of cell viability after thawing and a high rate of cell proliferation in both primary and permanent teeth.

Viability of Endothelial Cells in Preserved Human Saphenous Vein Allografts (보존된 사람 동종 복재정맥 이식편혈관 내피세포의 생활성에 관한 연구)

  • 지현근;김용진
    • Journal of Chest Surgery
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    • v.36 no.4
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    • pp.229-241
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    • 2003
  • Background:Autogenous vein is the preferred vascular graft for patients who require coronary artery bypass surgery or peripheral arterial bypass surgery. When an autogenous vein is not available, an allograft saphenous vein can be used as an alternative conduit. Although arterial homograft has been under investigation since the beginning of this century, the viability of endothelial cells and the optimum mode of storage for the venous and arterial allografts is controversial. In addition, with the recently gained knowledge of vascular endothelial functions, such as the production of nitric oxide or thrombomodulin, the viability and antigenicity of endothelial cells are being studied again. The purpose of this study was to evaluate the viability of endothelial cells in the preserved human saphenous veins. Material and Method: The veins were stored in a $4^{\circ}C$ RPMI (Roswell Park Memorial Institute) 1640 solution including 10% fetal calf serum, for one, three, five, seven or fourteen days. After the completion of the storage period, the veins were divided into two groups: Group I: studied immediately at $4^{\circ}C$ (cold) storage (I-1, I-3, I-5, I-7, I-14), and Group II: studied after storage at $-196^{\circ}C$ liquid nitrogen tank (cryopreservation) in an RPMI 1640 solution containing 10% DMSO for two weeks (II-1, II-3, II-5, II-7, II-14). Light microscopy and scanning electron microscopy (SEM), frypan blue exclusion testing, and thrombomodulin immunohistochemistry were performed. Result: In a morphometric study using SEM, there was statistically significant increase in Gundry Score in Groups I-7, I-14, II-5, II-7, and II-14 and showed cellular destruction (p<0.05). In the thrombomodulin immunohistochemistry study, there was reactivity in Groups I-1, I-3, and I-5, but the cryopreserved group revealed decreased reactivity (p<0.05). The trypan blue exclusion testing also showed superior viability in cold storage Group I. Conclusion: Venous allografts preserved in a $4^{\circ}C$ RPMI 1640 solution showed well preserved endothelial cellular integrity and thrombomodulin expression at up to seven days of preservation. Although cryopreservation of venous allografts stored in 10% DMSO -RPMI 1640 solution maintained the endothelial cellular structure on SEM, immunohistochemistry from the thrombomodulin and trypan blue exclusion testing showed decreased viability, It remains to be seen whether the decreased thrombomodulin reactivity could be restored, and what the nature to the relationship is between thrombomodulin and long-term patency of allografts.