• Title/Summary/Keyword: cold pretreatment

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Supercooling Pretreatment Improves the Shelf-Life of Freeze-Dried Leuconostoc mesenteroides WiKim32

  • Seul-Gi Jeong;In Seong Choi;Ho Myeong Kim;Ji Yoon Chang;Hae Woong Park
    • Journal of Microbiology and Biotechnology
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    • v.32 no.12
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    • pp.1599-1604
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    • 2022
  • Storage stability of freeze-dried lactic acid bacteria is a critical factor for their cost-effectiveness. Long-term storage of lactic acid bacteria enables microbial industry to reduce distribution costs. Herein, we investigated the effect of cold adaptation under supercooling conditions at -5℃ on the viability of Leuconostoc mesenteroides WiKim32 during the freeze-drying process and subsequent storage. Cold adaptation increased the thickness of exopolysaccharides (EPS) and improved the viability of freeze-dried Leu. mesenteroides WiKim32. Compared to non-adapted cells, cold-adapted cells showed a 35.4% increase in EPS thickness under supercooling conditions. The viability of EPS-hydrolyzed cells was lower than that of untreated cells, implying that EPS plays a role in protection during the freeze-drying process. Cold adaptation increased the storage stability of freeze-dried Leu. mesenteroides WiKim32. Fifty-six days after storage, the highest viability (71.3%) was achieved with cold adaptation at -5℃. When EPS-containing broth was added prior to the freeze-drying process, the viability further increased to 82.7%. These results imply that cold adaptation by supercooling pretreatment would be a good strategy for the long-term storage of Leu. mesenteroides WiKim32.

Effects of Pretreatment on the Field Germination Rate of Some Tree Seed (종자(種子)의 전처리(前處理)가 몇 수종(樹種)의 포장발아율(圃場發芽率)에 미치는 영향(影響))

  • Kim, Gab-Tae
    • Journal of Korean Society of Forest Science
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    • v.78 no.1
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    • pp.26-29
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    • 1989
  • To seek for a proper pretreatment method for increasing field germination rate, field germination rate of 5 tree species including Phellodendron amurense was investigated and was compared among pretreatment methods. The results obtained in this study were as follows ; 1. Field germination rates of Poncirus trifoliata and Fraxinus rhynchophylla among pretreatment methods were significantly different at 1% level, and that of Phellodendron amurense among pretreatment methods were significantly different at 5% level. In thses species, highest field germination rate was observed on the plot of cold moist stratification under the ground (Nochunmaejang ; during 166 days). 2. Field germination rates of Chaenomeles sinensis among pretreatment methods were significantly different at 1% level, and highest field germination rate was observed on the plot of cold moist stratification in the refrigerator (during 110days). 3. Field germination rates of Cudrania tricuspidata among pretreatment methods were not significantly different at 5% level.

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Studies on the Viability of Cultured Anther in Rice Anther Culture I. Changes of Respiratory Activity by Genotype and Cold-pretreatment (벼 배양약에서 약의 활력 연구 I. 품종 및 저온 전처리에 따른 호흡활성의 변화)

  • Seung Yeob, Lee;Seon Yong, Lee;Jang Soo, Choi
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.33 no.3
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    • pp.248-253
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    • 1988
  • The longer pollen stage grew to flowering stage, the higher anther respiratory rate in vivo became. and it was rapidly increased just before flowering. The anther respiratory rate in vitro showed the first and second peak points after 3-7 days and 9-1l days in culture, respectively, and fastest and highest in Daecheongbyeo with high sporophytic potentiality. It was lower in cold-pretreatment than non-treatment at the early days, but higher from 15 days after culture. The frequency of browning anthers was promoted by cold-pretreatment. The respiratory rate was not different between uncolored and browned anthers at 12 days, but it was higher in browned anthers after 24 days in culture.

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Sympathetic Dependency of Cold-evoked Pain Behavior Seen in Rats with Peripheral Neuropathy (신경병증성통증 모델쥐에서 냉자극 유발 통증의 교감신경성 의존도)

  • Choi, Byung-Ock;Choi, Yoon;Gwak, Young-Seob;Nam, Taick-Sang;Paik, Kwang-Se;Leem, Joong-Woo
    • The Korean Journal of Pain
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    • v.13 no.2
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    • pp.156-163
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    • 2000
  • Background: Peripheral nerve injury sometimes leads to chronic neuropathic pain such as causalgia. A subset of patients with causalgia have a sympathetically maintained pain which is often evoked by cooling stimuli. However, our knowledge on adrenergic receptor types responsible for cold-evoked pain that is sympathetically dependent is lacking. The present study was conducted to investigate subtypes of adrenoceptors involved in mediating cold-evoked pain that developed following peripheral nerve injury. Methods: Neuropathic surgery was performed by a unilateral ligation of L5 and L6 spinal nerves of rats. Behavioral sign of cold-evoked pain was examined for 5 min by measuring cumulative duration of time that the rat lifted its foot off a metal plate held at cold temperature ($5^{\circ}C$). Whether cold-evoked pain behavior was affected by antagonists of various subtypes of adrenoceptors, which were administered intraperitoneally before and after the ligation, was investigated. Results: After ligation, duration of foot lifting on the ligated side at cold temperature increased as compared to the pre-operative period. This increase maintained for the entire 40-day test period. Pretreatment with alpha-antagonist phentolamine produced a suppression of cold-evoked pain behavior that was not affected by beta-antagonist propranolol pretreatment. Prazosin, alpha-1 antagonist, suppressed cold- evoked pain behavior when treated either before or after nerve ligation. On the other hand, alpha-2 antagonist yohimbine was without effect on cold-evoked pain behavior whether it was treated before or after the ligation. Conclusions: The results suggest that peripheral nerve injury develops cold-evoked pain that is sympathetically dependent, and that alpha-1 adrenoreceptor plays a critical role for the generation of this type of pain in its initiation as well as maintenance.

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Treatment of surface water using cold plasma for domestic water supply

  • Nguyen, Dung Van;Ho, Phong Quoc;Pham, Toan Van;Nguyen, Tuyen Van;Kim, Lavane
    • Environmental Engineering Research
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    • v.24 no.3
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    • pp.412-417
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    • 2019
  • This paper presents the results of using cold plasma to treat surface water for domestic use purpose. Experimental results showed that cold plasma was an effective method for destroying bacteria in water. After treatment with cold plasma, concentration of coliform and Escherichia coli dramatically reduced. Besides, cold plasma significantly removed water odor, increased dissolved oxygen and decreased the concentration of chemical oxygen demand. However, cold plasma significantly raised the concentration of nitrite and nitrate. Other disadvantages of treating with cold plasma were conductivity increase and pH reduction. Pretreatment steps of coagulation, flocculation, sedimentation and sand filtration followed by disinfection with cold plasma exhibited a high efficiency in surface water treatment. All parameters of surface water after treatment by using the prototype satisfied with the allowance standard of domestic water quality.

Effects of Cold Pretreatment and Medium Composition on Anther Culture Initiation in Strawberry

  • Na, Hae-Young;Kim, Dae-Young;Chun, Chang-Hoo
    • Horticultural Science & Technology
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    • v.29 no.5
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    • pp.488-493
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    • 2011
  • Callus culture initiation of strawberry (Fragaria${\times}$ananassa Duch.) was investigated at different Murashige and Skoog (MS) medium strengths, types and concentrations of plant growth regulators, and incorporating a cold pretreatment period to determine the optimal nutritional and environmental conditions. No high quality callus was induced on MS media without auxin regardless of medium strength. When 6-benzylaminopurine (BA) was combined with indole acetic acid (IAA), naphthalene acetic acid (NAA), and 2,4-dichlorophenoxyacetic acid (2,4-D), high quality callus were highly induced compared to medium supplemented with auxin alone. When $0.5mg{\cdot}L^{-1}$ BA was combined with IAA, NAA, and 2,4-D, high quality callus induction was more effective than the medium supplemented with the other BA concentrations. The best combination of auxin and cytokinin for high quality callus induction was $1.0mg{\cdot}L^{-1}$ NAA and $0.5mg{\cdot}L^{-1}$ BA. Although the differences in callus induction were not significant, high quality callus induction at half strength MS medium was more effective than at full strength medium. When $30g{\cdot}L^{-1}$ sucrose was added to the half strength MS medium, the rate of high quality callus induction increased. The optimum cold pretreatment temperature and period for high quality callus induction were $4^{\circ}C$ and 72 h, respectively. Regeneration rate of high quality callus increased in MS medium supplemented with thidiazuron.

Effect of pertussis toxin pretreated centrally on blood glucose level induced by stress

  • Suh, Hong-Won;Sim, Yun-Beom;Park, Soo-Hyun;Sharma, Naveen;Im, Hyun-Ju;Hong, Jae-Seung
    • The Korean Journal of Physiology and Pharmacology
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    • v.20 no.5
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    • pp.467-476
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    • 2016
  • In the present study, we examined the effect of pertussis toxin (PTX) administered centrally in a variety of stress-induced blood glucose level. Mice were exposed to stress after the pretreatment of PTX (0.05 or 0.1 mg) i.c.v. or i.t. once for 6 days. Blood glucose level was measured at 0, 30, 60 and 120 min after stress stimulation. The blood glucose level was increased in all stress groups. The blood glucose level reached at maximum level after 30 min of stress stimulation and returned to a normal level after 2 h of stress stimulation in restraint stress, physical, and emotional stress groups. The blood glucose level induced by cold-water swimming stress was gradually increased up to 1 h and returned to the normal level. The intracerebroventricular (i.c.v.) or intrathecal (i.t.) pretreatment with PTX, a $G_i$ inhibitor, alone produced a hypoglycemia and almost abolished the elevation of the blood level induced by stress stimulation. The central pretreatment with PTX caused a reduction of plasma insulin level, whereas plasma corticosterone level was further up-regulated in all stress models. Our results suggest that the hyperglycemia produced by physical stress, emotional stress, restraint stress, and the cold-water swimming stress appear to be mediated by activation of centrally located PTX-sensitive G proteins. The reduction of blood glucose level by PTX appears to due to the reduction of plasma insulin level. The reduction of blood glucose level by PTX was accompanied by the reduction of plasma insulin level. Plasma corticosterone level up-regulation by PTX in stress models may be due to a blood glucose homeostatic mechanism.

Effects of Nefopam on Streptozotocin-Induced Diabetic Neuropathic Pain in Rats

  • Nam, Jae Sik;Cheong, Yu Seon;Karm, Myong Hwan;Ahn, Ho Soo;Sim, Ji Hoon;Kim, Jin Sun;Choi, Seong Soo;Leem, Jeong Gil
    • The Korean Journal of Pain
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    • v.27 no.4
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    • pp.326-333
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    • 2014
  • Background: Nefopam is a centrally acting non-opioid analgesic agent. Its analgesic properties may be related to the inhibitions of monoamine reuptake and the N-methyl-D-aspartate (NMDA) receptor. The antinociceptive effect of nefopam has been shown in animal models of acute and chronic pain and in humans. However, the effect of nefopam on diabetic neuropathic pain is unclear. Therefore, we investigated the preventive effect of nefopam on diabetic neuropathic pain induced by streptozotocin (STZ) in rats. Methods: Pretreatment with nefopam (30 mg/kg) was performed intraperitoneally 30 min prior to an intraperitoneal injection of STZ (60 mg/kg). Mechanical and cold allodynia were tested before, and 1 to 4 weeks after drug administration. Thermal hyperalgesia was also investigated. In addition, the transient receptor potential ankyrin 1 (TRPA1) and TRP melastatin 8 (TRPM8) expression levels in the dorsal root ganglion (DRG) were evaluated. Results: Pretreatment with nefopam significantly inhibited STZ-induced mechanical and cold allodynia, but not thermal hyperalgesia. The STZ injection increased TRPM8, but not TRPA1, expression levels in DRG neurons. Pretreatment with nefopam decreased STZ-induced TRPM8 expression levels in the DRG. Conclusions: These results demonstrate that a nefopam pretreatment has strong antiallodynic effects on STZ-induced diabetic rats, which may be associated with TRPM8 located in the DRG.

Effect of Different Pre-treatments on the Physicochemical and Antioxidant Activities of Cold-Vacuum Dried Peaches (전처리조건에 따른 냉풍감압건조 복숭아의 이화학적 및 항산화 활성)

  • Kwon, Gi-Man;Kim, Jae-Won;Youn, KwangSup
    • Korean Journal of Food Science and Technology
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    • v.45 no.4
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    • pp.466-472
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    • 2013
  • This study was performed to determine the effects of the pretreatment and cold-vacuum drying methods on the physicochemical properties and antioxidant activities of dried peaches. Moisture content was significantly lower with 0.3% NaCl treatment with cold-vacuum drying. The pH, brix and acid ratio (SS/TA) were the lowest with 1.0% soluble Ca treatment, while soluble solid and SS/TA were significantly higher with 0.1% vitamin C treatment compared to those with other treatments. The ${\delta}E$ and browning degree was lower in the pretreated sample compared to the untreated sample. Cutting strength of dried peaches was highest in the pretreated samples, and it was the highest with 1.0% soluble Ca treatment. Total sugar content with 0.1% vitamin C and 1.0% soluble Ca treatment was significantly higher than that with 0.3% NaCl treatment. The free sugar content was lower with 0.3% NaCl treatment but it was higher with 0.1% vitamin C and 1.0% soluble Ca treatment. The sensory evaluation result was highest with 0.1% vitamin C treatment. Phenolic compounds and antioxidant ability were the highest with the 0.1% vitamin C and 0.1% soluble Ca treatment; all the dried peaches showed relatively high antioxidant activities. These results suggest that pretreatment can affect the quality of dried peaches, showing that cold-vacuum drying can be applied for the production of high quality dried peach products.

Effects of Cold Shock Pretreatment and Carbohydrate Sources on Anther Culture of Rice (벼 약배양에 효과적인 배지조성 및 저온처리 방법)

  • Yi, Gi-Hwan;Won, Yong-Jae;Ko, Jong-Min;Park, Hyang-Mi;Cho, Jun-Hyeon;Oh, Byeong-Geun;Yang, Sae-Jun;Kim, Soon-Chul;Nam, Min-Hee
    • Journal of Plant Biotechnology
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    • v.30 no.4
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    • pp.369-373
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    • 2003
  • In spite of potential benefits of anther culture, low productivity of plant regeneration in some genotypes; e.g. tonsil and indica rice, is one of the major obstacles for practical use of anther culture. This study was conducted to improve cold shock method and carbohydrate source for increasing the efficiency of anther culture in rice. The most common carbon source, sucrose was replaced to maltose, which has two molecules of glucose. Maltose increased callus induction 1.4-to 1.8-fold higher in japonica rice, 3.2-to 11.6-fold in tongil types and 2.7-fold in indica rice IR50. Callus induction was increased from 0.2% to 12.5% in maltose medium compared to the medium supplemented with sucrose plus glucose in indica rice "Tetep". A simple procedure of vacuum packaging of panicles during cold shock treatment prolonged not only anther viability more than 15 days but also increased callus induction more than 2-fold compared to open-air storage (conventional method). Combining of above two methods, callus induction was increased 28 to 56% in japonica, 13 to 33% in tonsil type and 12 to 31% in indica rice. Plant regeneration was increased 14 to 35% in japonica, 10 to 20% in tonsil and 4 to 15% in indica rice, respectively.