• Title/Summary/Keyword: Cell division

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Fermentation Properties of Rice Added Yogurt Made with Various Lactic Acid Bacteria (유산균주의 종류에 따른 쌀 첨가 요구르트의 발효 특성)

  • Bae, H.C.;Paik, S.H.;Nam, M.S.
    • Journal of Animal Science and Technology
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    • v.46 no.4
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    • pp.677-686
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    • 2004
  • The objective of this experiment was to select the best strain of lactic acid bacteria for the manufacture of new type of yogurt with rice powders. Changes in pH, titratable acidity, viable cell counts, viscosity, organic acid contents, carbohydrates during fennentation were monitored and sensory evaluation were examined. The yogurt added with 4% rice or skim milk powders and L. salivarius ssp. salivarius culture did not reach pH 4.5, because the production of acids in this media for the culture was weak. The yogurt added with 4% rice or skim milk powder with L. casei, the pH was low and the titratable acidity was high, and therefore the quality of yogurt after 8 hours from fermentation was not high. The yogurt added with 4% rice or skim milk powders with a mixed culture of B. longum, L. acidophilus, Streptococcus salivarius ssp. thermophilus was considered best for achieving pH 4.5 and titratable acidity of 1.0 % from 8 to 14 hours. The yogurt with a mixed culture had more acetic acid. Galactose was accumulated when L. salivarius ssp. salivarius or the mixed culture were used for fermenting yogurt. In sensory evaluation, the yogurt with the mixed culture received high overall sensory score. From these results, a mixed culture of B. longum, L. acidophilus, Streptococcus salivarius ssp. thermophilus was identified as the best for the manufacture of yogurt added with rice powder.

Histone H3K4 Methyltransferase SET1A Stimulates the Adipogenesis of 3T3-L1 Preadipocytes (히스톤 H3K4 메칠화효소 SET1A에 의한 지방세포 분화 촉진)

  • Kim, Seon Hoo;Jung, Myeong Ho
    • Journal of Life Science
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    • v.27 no.10
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    • pp.1104-1110
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    • 2017
  • SET1A is a histone H3K4 methyltransferase that catalyzes di- and trimethylation of histone H3 at lysine 4 (H3K4). Mono-, di-, and trimethylations on H3K4 (H3K4me1, H3K4me2, and H3K4me3, respectively) are generally correlated with gene activation. Although H3K4 methylation is associated with the stimulation of adipogenesis of 3T3-L1 preadipocytes, it remains unknown whether SET1A plays a role in the regulation of adipogenesis of 3T3-L1 preadipocytes. Here, we investigated whether SET1A regulates 3T3-L1 preadipocytes' adipogenesis and characterized the mechanism involved in this regulation. SET1A expression increased during 3T3-L1 preadipocytes' adipogenesis. Consistent with the increased SET1A expression, the global H3K4me3 level had also increased on day 2 after the induction of adipogenesis in 3T3-L1 adipocytes. SET1A knockdown using siRNA in 3T3-L1 preadipocytes inhibited 3T3-L1 preadipocytes' adipogenesis, as assessed by Oil Red O staining and the expression of adipogenic genes, indicating that SET1A stimulates the adipogenesis of 3T3-L1 preadipocytes. SET1A knockdown inhibited the cell proliferation of 3T3-L1 cells during mitotic clonal expansion (MCE) via down-regulation of the cell cycle gene cyclin E1, as well as the DNA synthesis gene, dihydrofolate reductase. Furthermore, SET1A knockdown repressed peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$) expression during the late stage of adipogenesis. These results indicate that SET1A stimulates MCE and $PPAR{\gamma}$ expression, which leads to the promotion of 3T3-L1 preadipocytes' adipogenesis.

Marine Environmental and Phytoplankton Monitoring in Wando Coastal Waters in August during the Period of 2009-2010 (2009-2010년 8월 완도근해 해역의 해양환경 및 식물플랑크톤 모니터링)

  • Cho, Eun-Seob;Youn, Seok-Hyun
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.18 no.2
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    • pp.95-100
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    • 2012
  • This study was determined to analysis marine environmental and phytoplankton monitoring in Wando coastal waters in August during the period of 2009-2010 and provided the basic environmental data against Southwest Sea of Korea. In August, 2009, the distribution of water temperature and salinity showed an unique characteristics for all of stations, which was associated with a long duration of rainfall after July, 2009 and a lack of sunshine. In the lower of August, 2010, the stratification of water temperature and salinity was shown, which was caused by an intensive sunshine after the middle of August, 2010. Gangjin Bay and Gogeundo waters showed a highly different water temperature and transparency. It is thought that two regions have a distinct water mass and characteristics. In dissolved oxygen and oxygen saturation were higher according to higher water depth regardless of stations. In August, 2009, different dominant species occurred that Gangjin Bay showed a higher cell density of diatom, but Gonyaulax polygramma played an important role in dominant species in Gogeundo waters. It is associated with the introduction red tide water of G. polygramma occurring to southern coastal water in August, 2009. In August, 2010, diatom was extremely higher cell density compared with that of dinoflagellate that regarded as adaptive microrganism against higher quantity of suspended solid in Wando waters. Although Wando has a record of Cochlodinium red tide, this species may be difficult to grow and persist. Dominant species, diatom, play an important role in food organism for shellfish and forming a ecological lineage.

Effects of Onion Flesh and Peel on Chemical Components, Antioxidant and Anticancer Activities (양파 육질 및 껍질의 화학성분과 항산화 및 항암 활성 비교)

  • Jang, Joo-Ri;Lim, Sun-Young
    • Journal of Life Science
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    • v.19 no.11
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    • pp.1598-1604
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    • 2009
  • In order to determine chemical components of onion flesh and peel, general nutrients, vitamin C, and total flavonoids were measured. Onion peel showed less moisture (14.3%) and no vitamin C compared to onion flesh. Onion peel contained more amounts of total flavonoids compared to onion flesh. In addition, the inhibitory effects of solvent extracts from onion flesh and peel on $H_2O_$-induced oxidative stress and growth of cancer cell lines (AGS human gastric adenocarcinoma and HT-29 human colon cancer cells) were investigated. Acetone with methylene chloride (A+M) and methanol (MeOH) extracts from onion flesh and peel appeared to significantly reduce the levels of intracellular reactive oxygen species (ROS) (p<0.05) and a greater antioxidant effect was observed in onion peel. Among fractions, 85% aq. methanol showed a higher protective activity against oxidative stress in both flesh and peel and there was no effect in the water and hexane fractions. The growth of cancer cells exposed to medium containing extracts and fractions from onion flesh and peel was inhibited dose-dependently. The growth of AGS was inhibited more in both flesh and peel compared to HT-29, and onion peel was more effective than onion flesh. Among fractions, 85% aq. methanol showed the greatest effect on growth inhibition in both flesh and peel. $IC_{50}$ values of 85% aq. methanol fraction from onion flesh and peel on AGS were 0.04 and 0.03 mg/ml, respectively, while those on HT-29 were 0.23 and 0.04 mg/ml. From our results, 85% aq. methanol fraction had an inhibitory effect against oxidative stress and growth of cancer cells, suggesting that it may contain biological active compounds.

Characteristics of Sand-Silt Mixtures during Freezing-Thawing by using Elastic Waves (탄성파를 이용한 모래-실트 혼합토의 동결-융해 특성)

  • Kang, Mingu;Kim, Sangyeob;Hong, Seungseo;Kim, Youngseok;Lee, Jongsub
    • Journal of the Korean GEO-environmental Society
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    • v.15 no.5
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    • pp.47-56
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    • 2014
  • In winter season, the pore water inside the ground freezes and thaws repetitively due to the cold air temperature. When the freezing-thawing processes are repeated on the ground, the change in soil particle structure occurs and thus the damage of the infrastructure may be following. This study was performed in order to investigate the stiffness change of soils due to the freeze-thaw by using elastic waves. Sand-silt mixtures are prepared with in the silt fraction of 40 %, 60 % and 80 % in weight and in the degree of saturation of 40 %. The specimens are placed into the square freezing-thawing cell by the temping method. For the measurement of the elastic waves, a pair of the bender elements and a pair of piezo disk elements are installed on the cell, and a thermocouple is inserted into soils for the measurement of the temperature. The temperature of the mixtures is decreased from $20^{\circ}C$ to $-10^{\circ}C$ during freezing, is maintained at $-20^{\circ}C$ for 18 hours, is gradually increased up to the room temperature of $20^{\circ}C$ to thaw the specimens. The shear waves, the compressional waves and the temperature are measured during the freeze-thaw process. The experimental result indicates that the shear and the compressional wave velocities after thawing are smaller than those of before freezing. The velocity ratio of after thawing to before freezing of shear wave is smaller than that of the compressional wave. As silt fraction increases from 40 % to 80 %, the shear and compressional wave velocities are gradually increased. This study suggests that the freezing-thawing process in unsaturated soil loosens the soil particle structure, and the shear wave velocity reflects the effect of freezing-thawing more sensitively than the compressional wave velocity.

Isolation and Identification of Agarose-degrading Bacterium, Pseudoalteromonas sp. GNUM08122 (아가로오스 분해세균인 Pseudoalteromonas sp. GNUM08122 분리 및 동정)

  • Kim, Yu-Na;Jeong, Yeon-Kyu;Kim, Mu-Chan;Kim, Sung-Bae;Chang, Yong-Keun;Chi, Won-Jae;Hong, Soon-Kwang;Kim, Chang-Joon
    • Microbiology and Biotechnology Letters
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    • v.40 no.1
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    • pp.1-9
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    • 2012
  • This study's aim was to isolate microorganisms producing agarase with a high activity, with possible applications in improving the performance of the pretreatment processes for bioethanol production. Marine algaes were collected from the south coast of Korea, from which three kinds of microorganisms were isolated. After a 4-day culture of these strains at $25^{\circ}C$, crude enzymes were obtained from culture supernatant or cell-free extract by ammonium sulfate precipitation and membrane dialysis. Agarase activity was observed in these crude enzymes. Notably higher specific activity was observed in the crude enzyme obtained from the culture supernatant rather than that from the cell-free extract. This indicates that a secreted enzyme has a much greater activity than a cellular enzyme. Crude enzymes from the GNUM08122 strain were inferred to have ${\alpha}$-agarase activity because release of p-nitrophenol was observed, possibly due to the cleavage of p-nitrophenyl-${\alpha}$-D-galactopyranoside. The 16S rRNA sequence of GNUM08122 showed a close relationship to Pseudoalteromonas issachenkonii KMM 3549 (99.8%) and Pseudoalteromonas tetraodonis IMA 14160 (99.7%), which led us to assign it to the genus Pseudoalteromonas. Biochemical and physiological study revealed that this strain can grow well at $40^{\circ}C$ under a wide range of pH (pH 4~8) in high-salt conditions (10% NaCl).

Effect of Filter-feeding Bivalve (Corbiculidae) on Phyto- and Zooplankton Community (여과 섭식성 패류가 동 ${\cdot}$ 식물플랑크톤 군집에 미치는 영향)

  • Kim, Ho-Sub;Kong, Dong-Soo;Hwang, Soon-Jin
    • Korean Journal of Ecology and Environment
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    • v.37 no.3 s.108
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    • pp.319-331
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    • 2004
  • This study was conducted to evaluate the ecological impact of freshwater bivalve (Corbiculidae) on plankton communities in experimental enclosure systems (2 m ${\times}$ 2 m ${\times}$ 2 m). During the acclamation period of one month, cyanobacteria, including Microcystis viridis and Microcystis aeruginosa, dominated in both control and treatment enclosures with no noticeable density difference. After the addition of 100 mussels, dominant species of phytoplankton shifted from Microcystis to Scenedesmus in concert with slight decrease in the cell density and the increase of N/P ratio. However, cell density in the control quickly increased, accompanied with changes of dominant species to Oscillatoria spp. With the introduction of additional 500 musseles in the treatment enclosure, dominant phytoplankton species in both enclosures were replaced with Selenastrum spp. and Cryptomonas sp. In the initial stage, the total zooplankton abundance in the control was higher than that of treatment, but it was reversed after the addition 100 mussels. After mussel density increased up to 600 indivisuals, zooplankton density in the treatment decreased with dominance of small taxa, such as rotifers and nauplius. However, abundance and carbon biomass of large zooplankton, such as Bosmina longirostris and Diacyclops thomasi were maintained in a high level compared with those of control. During the study period, Chl. a concentration in mussel treatment and control increased with DIP and $NH_3-N$, respectively. Due to the increase of $NH_3-N$, especially after the introduction of additional 500 mussels, nitrogen limitation did not occur in the treatment enclosure in contrast with strong nutrient limitation occurred in the control. These results indicate that filter-feeding Corbicula could exert important impact on nutrient recycling and plankton community structure in a freshwater ecosystem, through direct feeding and competition for the same food resource as zooplankton on one hand, and through alteration of nutrient availability on the other.

Antioxidant Effect of Extracts from 9 Species of Forest Plants in Korea (국내 9종 산림식물 추출물의 항산화 효능)

  • Sim, Wan-Sup;Lee, Jong Seok;Lee, Sarah;Choi, Sun-Il;Cho, Bong-Yeon;Choi, Seung-Hyun;Han, Xionggao;Jang, Gill-Woong;Kwon, Hee-Yeon;Choi, Ye-Eun;Kim, Jong-Yea;Kim, Jong-Dai;Lee, Ok-Hwan
    • Journal of Food Hygiene and Safety
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    • v.34 no.4
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    • pp.404-411
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    • 2019
  • This study was carried out to investigate the antioxidant effects of extracts from 9 species of forest plants in Korea. DPPH, ABTS, $NaNO_2$, hydrogen peroxide radical scavenging activity and reducing power activity were evaluated to measure the antioxidant activities of plant extracts. As a result, Geranium thunbergii has been identified as the most effective antioxidant resource. Also, total phenolic content was highest in Geranium thunbergii ($303.94{\pm}0.63mg\;GAE/g$) among 9 species extracts. Total flavonoid content was highest in Rosa multiflora ($24.32{\pm}0.22mg\;QE/g$) and proanthocyanidin content was highest in Vitis ficifolia ($279.00{\pm}4.58mg\;CE/g$) among 9 species extracts. In addition, the protective effect of plant extracts in $H_2O_2-induced$ human dermal fibroblast (HDF) cell systems were also assessed. Significant protective effects in $H_2O_2-induced$ human dermal fibroblast (HDF) cell systems were found in all plant extracts, especially in Geranium thunbergii. These results suggest that Geranium thunbergii could be a potential natural resource for antioxidant activity.

Activity-guided Purification of N-benzyl-N-methyldecan-1-amine from Garlic and Its Antitumor Activity against CT-26 Colorectal Carcinoma in BALB/C Mice (활성추적분리법에 의해서 순수분리한 마늘 N-benzyl-N-methyldecan-1-amine이 CT-26 세포주 이식 BALB/C mice의 항암효과)

  • Seetharaman, Rajasekar;Choi, Seong Mi;Guo, Lu;Cui, Zheng Wei;Otgonbayar, Duuriimaa;Park, Ju Ha;Kwon, Young-Seok;Kwak, Jung Ho;Kwon, Young Hee;Min, Ji Hyun;Kang, Jum Soon;Choi, Young Whan
    • Journal of Life Science
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    • v.29 no.10
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    • pp.1062-1070
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    • 2019
  • A components of garlic (Allium sativum) have anti-proliferative effects against various types of cancer. We aimed to investigate the capacity of garlic compounds to anti-tumor on a various cancer cell lines. Fractionation of garlic extract, guided by antiproliferative activity against human gastric cancer (AGS) cells, has resulted in the isolation of N-benzyl-N-methyldecan-1-amine (NBNMA). We investigated the effect of newly isolated NBNMA from garlic cloves on the inhibition of the growth of CT-26, AGS, HepG2, HCT-116, MCF7, B16F10, and Sarcoma-180 cells for in vitro and CT-26 colon carcinoma cells in vivo. NBNMA exhibited an antiproliferative effect in CT-26 cells by apoptotic cell death. NBNMA exhibited down-regulation of anti-apoptotic Bcl-2 proteins and up-regulation of apoptotic Bad protein expression in western blot analyses. In addition, NBNMA meagre activated caspase 3 and caspase 9, initiator caspases of the extrinsic and intrinsic pathways of apoptosis. NBNMA treatment at a dose of 10 mg/kg for 21 days in experimental mice implanted with tumors resulted in significant reduction of the tumor weight (43%). NBNMA exhibited both in vitro and in vivo anticancer activity. These results indicate that NBNMA has promising potential to become a novel anticancer agent from garlic cloves for the treatment of colon carcinoma cancer.

Antioxidation and Functional Cosmetics Activity of Humulus japonicus Sieboid & Zucc. According to Collection Time and Extraction Solvent (채취 시기 및 추출 용매에 따른 환삼덩굴의 항산화 및 기능성 화장품 활성)

  • Chae, Jungwoo;Jo, Huiseon;Yeom, Hyeonji;Lee, Jin-young
    • Journal of Korean Society of Forest Science
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    • v.110 no.2
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    • pp.254-265
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    • 2021
  • As a result of measuring the polyphenol content of Humulus japonicus (HJ) extract according to the collection time and extraction solvent, bothhot water extract and 70% ethanol extract were collected and extracted in June, and the polyphenol content was high. When the harvesting time was the same, the polyphenol content of the ethanol extract was higher than that of the hot water extract. As a result of measuring the antioxidant activity of HJ extract by measuring electron-donating ability, SOD-like activity, and ABTS radical scavenging ability, HJ6E, which has the highest polyphenol content, showed the highest activity. In addition, in the case of the extract collected in August, the polyphenol content was similar. However, the antioxidant activity of the ethanol extract was high, sothe antioxidant activity remained high when extracted with 70% ethanol. As a result of measuring tyrosinase inhibitory activity for evaluating skin whitening activity, HJ6W did not show any activity. The activity at the highest concentration was 16.18% for HJ8W, 8.07% for HJ6E, and 14.7% for HJ8E. Therefore, the content of ingredients showing skin whitening activity was higher in August than in June. In the elastase inhibitory activity for evaluating the anti-wrinkle activityof the skin, the ethanol extract showed very little activity, and the hot water extract did not. In addition, since all extracts do not show astringent activity, it is judged that it is not appropriate to use HJ as a functional ingredient for preventing wrinkle formation. As a result of measuring the cell viability of HJ6E, which showed the highest polyphenol content and antioxidant activity, it showed a cell proliferation effect at low concentrationsbut strong cytotoxicity at concentrations above 50 ㎍/mL. In the case of the NO production inhibitory ability, as the concentration increased, the NO production of Raw 264.7 was suppressed. Theamount of NO production at 1,000 ㎍/mL decreased to 40.7%. However, whether these results are due to cytotoxicity or the extract's efficacy is a part that requires further research.