• Title/Summary/Keyword: Surface activity

Search Result 3,379, Processing Time 0.033 seconds

Effect of Modified Atmosphere Packaging on Preservation of Pumpkin Rice Cake (호박 설기떡의 저장성에 미치는 변형기체포장의 영향)

  • Moon, Ki-Bok;Kim, Hwan-Ki;An, Duck-Soon;Lee, Dong-Sun
    • Food Science and Preservation
    • /
    • v.17 no.6
    • /
    • pp.908-913
    • /
    • 2010
  • Modified atmosphere packaging (MAP) was evaluated for the storage of pumpkin rice cake as a means of preserving quality and extending shelf-life. Retail-sized amounts of rice cake were packaged in trays under different modified atmosphere conditions (air, vacuum, 60% $CO_2$/40% $N_2$ and 100% $CO_2$) using gas-barrier plastic film; control was in air-permeable stretch wrap. The packages were stored at $20^{\circ}C$ with periodical measurement of package atmosphere and cake quality attributes. The modified atmosphere packages of 60% $CO_2$/40% $N_2$ and 100% $CO_2$ inhibited the growth of molds/yeasts completely and significantly retarded the growth of aerobic bacteria. All the packages except that of 100% $CO_2$ showed the reduction of internal $O_2$ concentration and increase of the $CO_2$ with storage time due to the microbial activity. There has been slight decrease of $CO_2$ concentration for 60% $CO_2$/40% $N_2$ and 100% $CO_2$ packages just after start of the storage possibly due to dissolution of headspace $CO_2$ into the cake. Any MAP conditions did not affect the retrogradation of the rice cake. Surface color of the cake within affordable microbial quality limit was not affected significantly by packaging conditions.

The Effect of Linarin on LPS-Induced Cytokine Production and Nitric Oxide Inhibition in Murine Macrophages Cell Line RAW264.7

  • Kim, Kyung-Jae;Han, Shin-Ha;Sung, Ki-Hyun;Yim, Dong-Sool;Lee, Sook-Kyeon;Lee, Chong-Kil;Ha, Nam-Ju
    • Archives of Pharmacal Research
    • /
    • v.25 no.2
    • /
    • pp.170-177
    • /
    • 2002
  • The herb, Chrysanthemum zawadskii var, latilobum commonly known as Gu-Jul-Cho in Korea, used in traditional medicine to treat pneumonia, bronchitis, cough, common cold, pharyngitis, bladder-related disorders, gastroenteric disorders, and hypertension. Linarin is the main active compound and the biological mechanisms of its activity are unclear. It is believed that effects of this herb may be exerted through the pluripotent effectors of linarin due to its ability to treat a variety of afflictions. In this study, the effects of linarin on the mouse macrophages cell line, RAW 264.7, were investigated. It was found that linarin could activate macrophages by producing cytokines. Monocytes and tissue macrophages produce at least two groups of protein mediators of inflammation, interleukin 1 (IL-1 ) and the tumor necrosis factor (TNF). Recent studies have shown that TNF and IL-1 modulate the inflammatory function of endothelial cells, leukocytes, and fibroblasts. $TNF-{\alpha}$ production by macrophages treated with linarin occured in a dose dependent manner However, IL-1 production was largely unaffected by this natural product. This study demonstrated the ability of linarin to activate macrophages both directly and indirectly. Linarin also affect both cytosine production and nitric oxide inhibition, in addition to the expression of some surface molecules. Nitric oxide (NO), derived from L-argin-ine, is produced by two forms(constitutive and inducible) of nitric oxide synthase (NOS). The NO produced in large amounts by inducible NOS is known to be responsible for the vasodilation and hypotension observed in septic shock. Linarin was found to inhibit NO production in the LPS-activated RAW 264.7 cells. Linarin may be a useful candidate as a new drug for treating endotoxemia and the inflammation accompanied by NO overproduction. The linarin-treated total Iymphocytes exhibited cytotoxicity in a dose dependent manner between $20{\;}{\mu}g/ml{\;}and{\;}40{\;}{\mu}g/ml$. These results suggest that linarin may function through macrophage activation.

Expression of MEK1 Fusion Protein in Yeast for Developing Cell Based Assay System, a Major Substrate of LeTx (Yeast내에서 MEK1 융합 단백질 발현 및 Lethal Factor 활성 검증)

  • Hwang, Hye-Hyun;Kim, Joung-Mok;Choi, Kyoung-Jae;Park, Hae-Chul;Han, Sung-Hwan;Chung, Hoe-Il;Koo, Bon-Sung;Park, Joon-Shik;Yoon, Moon-Young
    • Korean Journal of Microbiology
    • /
    • v.42 no.3
    • /
    • pp.195-198
    • /
    • 2006
  • Lethal toxin is a critical virulence factor of anthrax. It is composed two protein: protective antigen (PA) and lethal factor (LF). PA binds to specific cell surface receptors and, forms a membrane channel that mediates entry of LF into the cell. LF is a zinc-dependent metalloprotease, which cleaves MKKs [MAPK (mitogen-activated protein kinase) kinases] at peptide bonds very close to their N-termini. In this study, we suggest application of cell-based assays in the early phase of drug discovery, with a particular focus on the use of yeast cells. We constructed MEK1 expression system in yeast to determine LF activity and approached cell-based assay system to screen inhibitors, in which the results covering the construction of LF-substrate in yeast expression vector, expression, and LF-mediated proteolysis of substrate were described. These results could provided the basic steps in design of cell-based assay system with the high efficiency, rapidly and easy way to screening of inhibitors.

The Optimum Stabilization Conditions of TiO2-containing Pitch Fiber (TiO2 함유 피치섬유의 최적 안정화 조건)

  • Eom, Sang Yong;Lee, Chang Ho;Park, Kwan Ho;Ryu, Seung Kon
    • Korean Chemical Engineering Research
    • /
    • v.45 no.3
    • /
    • pp.269-276
    • /
    • 2007
  • $TiO_2$-containing pitch fibers were prepared and various stabilization variables were investigated by characterizations of the fibers and behaviors of $TiO_2$ particles in the optimum stabilization conditions. When pitch fiber was stabilized by air at the optimum condition, the fiber weight increased as an increase of the stabilization temperature and a decrease of $TiO_2$ concentration. The carbonization yield was 71~82 wt.%, showing a decrease of the yield with the $TiO_2$ increase caused by the catalytic activity of $TiO_2$ to combustion. During the stabilization, newly developed carbonyl and carboxyl groups were introduced on the fiber surface and cross-linking reactions were progressed resulting the thermosetting property, which was verified by the replacement of hydrogen with oxygen. Pore size of the activated carbon fiber was increased by an increase in $TiO_2$ concentration. In the considerations of the aggregation behaviors of the $TiO_2$ particles, the optimum stabilization conditions of 0.5 wt.% $TiO_2$ containing petroleum-based pitch fiber were suggested as $280^{\circ}C$, 3 hr.

Optimization of Microwave-assisted Extraction Conditions for Production of Bioactive Material from Corn Stover (옥수수 대로부터 생리활성물질 생산 증대를 위한 마이크로파 추출 공정 최적화)

  • Min, Bora;Han, Yeojung;Lee, Dokyeoung;Jo, Jaemin;Jung, Hyunjin;Kim, Jin-Woo
    • Korean Chemical Engineering Research
    • /
    • v.56 no.1
    • /
    • pp.66-72
    • /
    • 2018
  • Corn stover is known as a good candidate for a functional food ingredient when the main lignocellulosic material, lignin, is used as bioactive materials as form of polyphenolic compounds. The purpose of this study was to determine the microwave extraction conditions under which total phenolic compounds (TPC) and flavonoid contents of corn stover were maximized. Microwave-assisted extracts using sulfuric acid ranging from 0 to 1.0 mol with extraction time between 40 and 240 sec were conducted by using response surface methodology (RSM). Microwave power showed significant effects (p<0.05) and the concentrations of TPC and flavonoids increased with increased level of microwave power and extraction time. The optimum conditions for corn stover extraction were determined as 698.6 W, 240 sec, and 0 mol sulfuric acid, and the predicted value of TPC and flavonoid is 82.4 mg GAE/g DM and 18.1 mg/g DM, respectively. Microwave extraction was evaluated as an economic process with low energy consumption, short extraction and high extraction yield of bioactive including TPC and flavonoids compared to conventional extractions.

Quality Characteristics of White Bread Manufactured with Shinan Seomcho (Spinacia oleracea L.) Powder (신안 섬초(시금치) 분말을 대체한 식빵의 품질특성)

  • Ko, Sang-Heui;Bing, Dong-Joo;Chun, Soon-Sil
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.42 no.5
    • /
    • pp.766-773
    • /
    • 2013
  • In this study, white bread was prepared with Shinan seomcho powder (SSP). Different amounts of SSP were tested (2, 4, 6 and 8%) to determine the optimal amount. The samples and a control were compared for quality characteristics, including pH, total titratable acidity, specific volume, baking loss, moisture content, water activity, color, textural characteristics, external and internal surface appearances, and sensory qualities. As the SSP increased, the total titratable acidity of the dough decreased (pH increased), and a decreased specific volume and baking loss was observed as well. However, the total titratable acidity and pH of the bread did not show significant differences among the samples. The moisture content was highest at a substitution level of 8%, and increased with increasing SSP contents. The crumb L value, a value, and resilience decreased with increasing SSP, whereas the crumb b value and hardness increased. Color, flavor, softness and overall acceptability were highest for the control group and were lowest for the 8% group. This likely reflects the high value of a grassy flavor, green tea taste, bitterness, astringency, and off-flavor at addition level of 8%. As a results, the optimum amount of SSP to add for baking bread would be 2~4%.

The Mechanical Sensitivity at Interfaces between Bone and Interbody Cage of Lumbar Spine Segments (Lumbar spine 의 뼈와 Interbody cage의 접촉면에서 기계공학적 민감성 고찰)

  • Kim Y.
    • Journal of Biomedical Engineering Research
    • /
    • v.21 no.3 s.61
    • /
    • pp.295-301
    • /
    • 2000
  • It is known that among many factors, relative micromotion at bone/implant interfaces can hinder bone ingrowth into surface pores of an implant. Loading conditions, mechanical properties of spinal materials, friction coefficients at the interfaces and geometry of spinal segments would affect the relative micromotion and spinal stability. A finite clement model of the human lumbar spine segments (L4-L5) was constructed to investigate the mechanical sensitivity at the interfaces between bone and cage. Relative micromotion. Posterior axial displacement. bone stress, cage stress and friction force were predicted in changes of friction coefficients, loading conditions. bone density and age-related material/geometric properties of the spinal segments. Relative micromotion (slip distance in a static loading means relative micromotion in routine activity) at the interfaces increased significantly as the mechanical properties of cancellous bone, annulus fibers or/and ligaments decrease or/and as the friction coefficient at the interfaces decreases. The contact normal force at the interfaces decreased as cancellous bone density decreases or/and as the friction coefficient increases A significant increase of slip distance at anterior annulus occurred with an addition of torsion to compressive preload. Relative micromotion decreased with an increase of disc area. In conclusion. relative micromotion, stress response. Posterior axial displacement and contact normal force are sensitive to the friction coefficient of the interfaces, bone density, loading conditions and age-related geometric/material changes.

  • PDF

Conditions for Obtaining Optimum Polyphenol Contents and Antioxidant Activities of Korean Berry and Green Tea Extracts (반응표면분석을 이용한 오가자, 오디, 복분자 및 녹차의 항산화 활성 추출 최적화)

  • Lee, Ji-Hye;Kim, Yang;Lee, Suyong;Yoo, Sang-Ho
    • Korean Journal of Food Science and Technology
    • /
    • v.46 no.4
    • /
    • pp.410-417
    • /
    • 2014
  • Berries and green tea are underutilized in the food industry despite their great potential as a functional food ingredients. The purpose of this study was to determine the extraction conditions under which total phenolic contents and antioxidant activities of berry and green tea extracts are maximized. Extracts produced using 0-80% ethanol and temperatures ranging from $5-65^{\circ}C$ were evaluated for total phenolic content (TP), as well as for DPPH and ABTS radical-scavenging activities by using response surface methodology. Both ethanol and temperature had significant effects (p<0.05). Ogaja extract produced at $67^{\circ}C$ by using 33% ethanol yielded maximum TP, ABTS, and DPPH values of 23.74 mg GAE/g, 19.77, and 25.04 mg VCE/g, respectively. Optimum conditions for mulberry and raspberry extraction were found to be $65^{\circ}C$ by using 69% and 40% ethanol, respectively. Mulberry and raspberry extracts had TP, DPPH, and ABTS values of 20.74 mg GAE/g, 23.55, and 35.44 mg VCE/g, and 26.08 mg GAE/g, 39.93, and 55.60 mg VCE/g, respectively. Green tea extraction at $57^{\circ}C$ by using 43% ethanol was found to be optimal, yielding TP, ABTS, and DPPH values of 101.15 mg GAE/g, 171.38, and 177.56 mg VCE/g, respectively.

The compensation for damage by space accidents (우주손해배상법에 관한 약간의 고찰)

  • Kim, Sun-Ihee
    • The Korean Journal of Air & Space Law and Policy
    • /
    • v.22 no.2
    • /
    • pp.3-25
    • /
    • 2007
  • In 2002 Republic of Korea successfully launched a self-made mined proportion rocket and it is expected that she will be able to have own space launching system by 2010. According to Article 14 of the Space Exploration Promotion Act, a new law should be established to impose the limit of compensation for the damage by space accident. Therefore, The Space Accident Liability Act was passed in Korean Congress on Nov. 22, 2007 and it will be enforced in six months. The purpose of this Act is to provide reparation for the damage of the third parties that a launch causes; and the Commonwealth should be insured against any possible space accidents to pay for such a damage. Here space accident means the damages to our life, body, and properties from the launching of space objects. There should be an actual loss to establish the compensation of Liability Act. Article 2 in Liability Act defines "damage" as follows: the term "damage" means loss of life, personal injury or loss of or damage to property of persons. Physical and material damages are included in the conception of damage. The meaning of a launching includes any test launch and launch for a real arrangement which will ultimately provides a wide range of compensation. Article 4 indicates that absolute liability should be imposed in compensating for damage by space accidents. Article 4 also indicates that a launching party should be absolutely liable to compensate for the damage caused by its space object on the surface of the Earth. In general, liability stands where fault is. But if the activity is ultra-hazardous and causes serious harm, the individual needs to compensate for the damage unlimitedly. Because of the many launchings for the Seattleite launching, a launching organization is obligated to the liability insurance in preparation for the space accidents. According to the Article 6 of Space Accident Liability Act, to be insured for the compensation for damage is obligatory. It says: "In accordance with Article 11 in the Space Exploration Promotion Act, the person who wants to receive an approval f3r launching needs to be insured in compensation for the possible damage by space accidents.

  • PDF

The Effect of Treatment with Intrathecal Ginsenosides in a Rat Model of Postoperative Pain (백서를 이용한 수술 후 통증 유발 모형에서 척수강 내로 투여한 Ginsenosides의 효과)

  • Shin, Dong Jin;Yoon, Myung Ha;Lee, Hyung Gon;Kim, Woong Mo;Park, Byung Yun;Kim, Yeo Ok;Huang, Lan Ji;Cui, Jin Hua
    • The Korean Journal of Pain
    • /
    • v.20 no.2
    • /
    • pp.100-105
    • /
    • 2007
  • Background: Ginseng has been used to manage various types of pain in folk medicine. This study characterized the effect of treatment with intrathecal ginsenosides, the active components of ginseng in a postoperative pain model. Methods: Male Sprague-Dawley rats were implanted with lumbar intrathecal catheters. An incision was made in the plantar surface of the hindpaw. Withdrawal thresholds following the application of a von Frey filament to the wound site were measured. To determine the role of the opioid or GABA receptors following treatment with the ginsenosides, naloxone, bicuculline (a $GABA_A$ receptor antagonist), and saclofen (a $GABA_B$ receptor antagonist) were administered intrathecally 10 min before the delivery of the ginsenosides and the changes of the withdrawal thresholds after application of the von Frey filament were Observed. Results: Treatment with the intrathecal ginsenosides increased the withdrawal threshold in a dose dependent manner. Pre-treatment with intrathecal naloxone reversed the antinociceptive effect of the ginsenosides. However, pre-treatment with intrathecal bicuculline and saclofen failed to have an effect on the activity of the ginsenosides. Conclusions: These results suggest that ginsenosides are effective to alleviate the postoperative pain evoked by paw incision. The opioid receptor, but not GABA receptors, may be involved in the antinociceptive action of the ginsenosides at the spinal level.