• Title/Summary/Keyword: Chemical assay

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Detection of Spoilage Odors in Beef Using R-index and Pseudomonas Growth during Storage (쇠고기의 저장 중 R-index에 의한 부패취 발생시점과 Pseudomonas의 증식과의 비교 분석)

  • Byeon, Ko Eun;Park, Han Jo;An, Soo Rim;Hong, Kwang Won;Min, Sang Gi;Chung, Ku Young;Won, Kee Hoon;Lee, Seung Ju
    • Food Engineering Progress
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    • v.13 no.2
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    • pp.117-121
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    • 2009
  • Detection of spoilage odors from beef during storage was investigated using sensory evaluation with R-index, and microbial assay for Pseudomonas. Beef samples were tested to measure the flavor changes, which were converted to R-index, and the Pseudomonas levels during storage. There was a steep rise in R-index until 36 hr after storage at 25$^{\circ}C$, and then a gentle rise from 48 hr, whereas, there was a steady rise in R-index in the whole range of storage at 5$^{\circ}C$. Detection time of spoilage odors according to R-index was statistically analyzed at $\alpha$=5% to be at 30.92${\pm}$3.47 hr and 169.80${\pm}$11.27 hr for 25 and 5$^{\circ}C$ storage, respectively, and analyzed at $\alpha$=1% to be 34.80${\pm}$4.01 and 176.41${\pm}$9.89 hr for 25 and 5$^{\circ}C$ storage, respectively. At the detection times of spoilage odors, the Pseudomonas levels were found to be almost the same, but less than 6-7 log CFU/g generally known as a standard level at occurrence of spoilage odors in beef. This indicated that some other factors than the Pseudomonas reactions could be associated with generation of spoilage odors.

Effect of antioxidation and antibacterial activity on crude extract and Characterization of American Cockroaches (Periplaneta americana L.) in Korea (국내 서식 미국바퀴(Periplaneta americana L.)의 특성 및 추출물의 항산화·항균 효과)

  • Kim, Jung-Eun;Kim, Seon-Gon;Kang, Sung-Ju;Kim, Chun-Sung;Choi, Yong-Soo
    • Journal of Sericultural and Entomological Science
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    • v.53 no.2
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    • pp.135-142
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    • 2015
  • The American cockroaches, Periplaneta americana L. was the most important worldwide pest species. It has been an public health problems. We were determinated life cycle and extraction of crude extracts by chemical reagents from cockraches (P. americana L.). The extracted crude solution has been antibacterial activity to gram negative bacteria (Pseudomonas aeruginosa, $6.44{\pm}1.03mm$), gram positive bacteria (Bacillus subtilis, $1.88{\pm}0.40mm$), and fungus (Candida albicans, $5.61{\pm}0.57mm$) using radial diffusion assay. We were analysed of up-regulation of Glutathione-S-transferases (GSTs) stimulation, indicating that antioxidantial protein from various classes are simultaneously expressed in a single insect upon infection or injury. The gene from Periplaneta americana L. were cloned, analysed sequence, and measured protein expression by Real Time PCR (Polymerase Chain Reaction).

Chemical components and hepato-protective effect of Lentinula edodes fermented by lactic acid bacteria (표고 유산균 발효물의 성분 및 간기능 보호 효과)

  • Im, Seung-Bin;Kim, Kyung-Je;Jin, Seong-Woo;Koh, Young-Woo;Ha, Neul-I;Jeong, Hee-Gyeong;Lee, Jae-Keun;Yun, Kyeong-Won;Seo, Kyoung-Sun
    • Journal of Mushroom
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    • v.19 no.3
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    • pp.191-199
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    • 2021
  • This study was conducted to improve the useful components and biological activity of Lentinula edodes fermented by lactic acid bacteria (LAB). Three LAB strains (Lactobacillus brevis KCCM 11904, L. plantarum KCCM 354469, and L. fermentum KCCM 12116) were inoculated and used for L. edodes hot water extract (10%, 20%, 30%) fermentation. LAB fermentation of L. edodes hot water extracts decreased pH and thus were more acidic than non-fermented L. edodes hot water extract. β-glucan and ergothioneine contents were increased by L. edodes in a concentration-dependent manner. The ergothioneine and β-glucan contents were highest in fermented with 30% L. edodes hot water extract fermented by L. plantarum and L. brevis (40.48 mg/100 g and 13.94%, respectively). The hepato-protective effect of fermented L. edodes hot water extracts by the three LAB were tested using Sprague-Dawley rat primary hepatocytes. In primary hepatocytes obtained following liver injury induced by acetaminophen, fermented L. edodes hot water extracts by the three LAB showed protective effects, as evident by reduction of the aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase liver markers. The collective results indicate that the fermented L. edodes hot water extracts obtained using LAB are potentially valuable in preventing or treating liver disease.

A Comparative Study on the Chemical Characteristics and Antioxidant Effects of Sea Mustards Sourced from Different Areas in Taejongdae (태종대산 5종 돌미역의 화학성분 및 항산화활성 비교)

  • Kim, Hojun;Jayapala, HPS;Jo, Won Hee;Nam, Hyung Sik;Lim, Sun Young
    • Journal of Life Science
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    • v.31 no.6
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    • pp.559-567
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    • 2021
  • This study compared the nutritional characteristics and antioxidant effects of sea mustards sourced from five different areas (Barammaegi, Gultongmeori, Chanmulgae, Johongtaek, and Goraedeung) in Taejongdae, Youngdo, Busan. The contents of total flavonoids and phenols and fatty acid composition were measured. To evaluate their antioxidant effects, 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays were used. Acetone/methylene chloride (A+M) extracts from all the sea mustards contained higher amounts of total flavonoids and phenols than methanol (MeOH) extracts. Among the sea mustards obtained from the different areas, the total flavonoid and total phenolic content of the A+M extract of the sea mustard from Gultongmeori was 1.44±0.04 mg/g and 1.72±0.06 mg/g, respectively. In terms of the fatty acid composition, the Gultongmeori sea mustard had higher percentages of total n-6, total n-3, eicosapentaenoic acid (EPA, 20:5n-3), and docosahexaenoic acid (DHA, 22:6n-3) than the sea mustards from the other areas. The A+M extract of the sea mustard from Gultongmeori was more effective in terms of scavenging free radicals as compared with that of the other sea mustards, as assessed by the DPPH and ABTS assays (p<0.05). In a 120-minute reactive oxygen species (ROS) production assay, all the extracts tested decreased cellular ROS production induced by H2O2 compared to that produced by exposure to an extract-free control (p<0.05). The extracts from Barammaegi and Gultongmeori had a greater inhibitory effect on cellular ROS production. These results indicated that the antioxidant effects of sea mustards might be associated with a higher amount of flavonoids and phenols. This study suggests that food-processed products from sea mustard can be developed as functional foods for promoting health in the local population.

Anti-obesity effect of radish leaf extracts on high fat diet-induced obesity in mice (고지방식이를 통해 비만이 유발된 마우스에서 무청 추출물의 항비만 효과)

  • Lee, Yun-Seong;Seo, Young Ho;Kim, Ji Yong
    • Korean Journal of Food Science and Technology
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    • v.54 no.3
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    • pp.297-305
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    • 2022
  • The goal of this study was to evaluate the anti-obesity effect of radish leaf extracts (MU-C) and radish leaf extracts with 3% citric acid (MU-CA) in a high-fat diet (HFD)-induced C57BL/6 mice. The effects of radish leaf extracts on adipogenesis were also investigated using 3T3-L1 adipocytes. As determined by Oil red O staining, MU-C inhibited adipogenesis in 3T3-L1 adipocytes. Four-week-old male C57BL/6 mice were fed an HFD for 6 weeks and then treated with radish leaf extracts (500 mg/kg, p.o.) for 6 weeks. Then, the serum levels of Aspartate aminotransferase, Alanine aminotransferase, Total cholesterol, Triglyceride and low-density lipoprotein cholesterol in the mice were measured using an automatic chemical analyzer and enzyme-linked immunosorbent assay. Administration of MU-C significantly reduced the fat weight when compared with HFD controls. As confirmed by histopathologic analysis, adipose tissue size markedly decreased in mice treated with MU-C. Therefore, this study could provide a basis for investigating the clinical use of MU-C as an agent for preventing obesity.

Biochemical Assessment of Deer Velvet Antler Extract and its Cytotoxic Effect including Acute Oral Toxicity using an ICR Mice Model (ICR 마우스 모델을 이용한 녹용 추출물의 생화학적 평가 및 급성 경구 독성을 포함한 세포 독성 효과)

  • Ramakrishna Chilakala;Hyeon Jeong Moon;Hwan Lee;Dong-Sung Lee;Sun Hee Cheong
    • Journal of Food Hygiene and Safety
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    • v.38 no.6
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    • pp.430-441
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    • 2023
  • Velvet antler is widely used as a traditional medicine, and numerous studies have demonstrated its tremendous nutritional and medicinal values including immunity-enhancing effects. This study aimed to investigate different deer velvet extracts (Sample 1: raw extract, Sample 2: dried extract, and Sample 3: freeze-dried extract) for proximate composition, uronic acid, sulfated glycosaminoglycan, sialic acid, collagen levels, and chemical components using ultra-performance liquid chromatography-quadrupole-time-of-light mass spectrometry. In addition, we evaluated the cytotoxic effect of the deer velvet extracts on BV2 microglia, HT22 hippocampal cells, HaCaT keratinocytes, and RAW264.7 macrophages using the cell viability MTT assay. Furthermore, we evaluated acute toxicity of the deer velvet extracts at different doses (0, 500, 1000, and 2000 mg/kg) administered orally to both male and female ICR mice for 14 d (five mice per group). After treatment, we evaluated general toxicity, survival rate, body weight changes, mortality, clinical signs, and necropsy findings in the experimental mice based on OECD guidelines. The results suggested that in vitro treatment with the evaluated extracts had no cytotoxic effect in HaCaT keratinocytes cells, whereas Sample-2 had a cytotoxic effect at 500 and 1000 ㎍/mL on HT22 hippocampal cells and RAW264.7 macrophages. Sample 3 was also cytotoxic at concentrations of 500 and 1000 ㎍/mL to RAW264.7 and BV2 microglial cells. However, the mice treated in vivo with the velvet extracts at doses of 500-2000 mg/kg BW showed no clinical signs, mortality, or necropsy findings, indicating that the LD50 is higher than this dosage. These findings indicate that there were no toxicological abnormalities connected with the deer velvet extract treatment in mice. However, further human and animal studies are needed before sufficient safety information is available to justify its use in humans.

CELL CULTURE STUDIES OF MAREK'S DISEASE ETIOLOGICAL AGENT (조직배양(組織培養)에 의한 Marek 병(病) 병원체(病原體)의 연구(硏究))

  • Kim, Uh-Ho
    • Korean Journal of Veterinary Research
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    • v.9 no.1
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    • pp.23-62
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    • 1969
  • Throughout the studies the following experimental results were obtained and are summarized: 1. Multiplication of agents in primary cell cultures of both GF classical and CR-64 acute strain of Marek's disease infected chicken kidneys was accompanied by the formation of distinct transformed cell foci. This characteristic nature of cell transformation was passaged regularly by addition of dispersed cell from infected cultures to normal chicken kidney cell cultures, and also transferred was the nature of cell transformation to normal chick-embryo liver and neuroglial cell cultures. No cytopathic changes were noticed in inoculated chick-embryo fibroblast cultures. 2. The same cytopathic effects were noticed in normal kidney cell monolayers after the inoculation of whole blood and huffy coat cells derived from both forms of Marek's disease infected chickens. In these cases, however, the number of transformed cell foci appearing was far less than that of uninoculated monolayers prepared directly from the kidneys of Marek's disease infected chickens. 3. The change in cell culture IS regarded as a specific cell transformation focus induced by an oncogenic virus rather than it plaque in slowly progressing cytopathic effect by non-oncogenic viruses, and it is quite similar to RSV focus in chick-embryo fibroblasts in many respects. 4. The infective agent (cell transformable) were extremely cell-associated and could not be separated in an infective state from cells under the experimental conditions. 5. The focus assay of these agents was valid as shown by the high degree of linear correlation (r=0.97 and 0.99) between the relative infected cell concentration (in inoculum) and the transformed cell foci counted. 6. No differences were observed between the GF classical strain and the CR-64 acute strain of Marek's disease as far as cell culture behavior. 7. Characterization of the isolates by physical and chemical treatments, development of internuclear inclusions in Infected cells, and nucleic acid typing by differential stainings and cytochemical treatments indicated that the natures of these cell transformation agents closely resemble to those described fer the group B herpes viruses. 8. Susceptible chicks inoculated with infected kidney tissue culture cells developed specific lesions of Marek's disease, and in a case of prolonged observation after inoculation (5 weeks) the birds developed clinical symptoms and gross lesions of Marek's disease. Kidney cell cultures prepared from those inoculated birds and sacrificed showed a superior recovery of cell transformation property by formation of distinct foci. 9. Electron microscopic study of infected kidney culture cells (GF agent) by negative staining technique revealed virus particles furnishing the properties of herpes viruses. The particle was measured about $100m{\mu}$ and, so far, no herpes virus envelop has been seen from these preparations. 10. No relationship of both isolates to avian leukosis/sarcoma group viruses and PPLO was observed.

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