• 제목/요약/키워드: serial dilution

검색결과 67건 처리시간 0.023초

Expression of a Functional Human Tumor Necrosis Factor-${\alpha}$ (hTNF-$\alpha$) in Yeast Saccharomyces cerevisiae

  • Park, Seung-Moon;Mo, Ae-Young;Jang, Yong-Suk;Lee, Jae-Hwa;Yang, Moon-Sik;Kim, Dae-Hyuk
    • Biotechnology and Bioprocess Engineering:BBE
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    • 제9권4호
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    • pp.292-296
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    • 2004
  • The recombinant soluble human tumor necrosis factor-alpha (hTNF-$\alpha$) was expressed in a yeast Saccharomyces cerevisiae and its cytotoxicity was evaluated. A cDNA encoding hTNF-$\alpha$ was placed under the control of two different promoters: a glyceraldehyde-3-phosphate dehydrogenase (GPD) promoter and a yeast hybrid ADH2-GPD promoter, consisting of alcohol dehydrogenase II (ADH2) and the GPD promoter. A Northern blot analysis revealed that, although variation in the expression level of hTNF-$\alpha$ existed among transformants, the higher expression was obtained with the GPD promoter. Expressed hTNF-$\alpha$ protein (rhTNF-$\alpha$) was successfully secreted into the culture medium, producing 2.5 mg per liter of culture filtrate, with no changes in cell growth. The bioassay for observing the cytotoxicity to the murine L929 fibroblast cell line, with serial dilution of rhTNF-$\alpha$, indicated that the secreted rhTNF-$\alpha$ was bioactive and its dose-response was improved eight to ten times over that of the E. coli-derived rhTNF-$\alpha$.

한국산 천연 Naringin의 항균작용 및 안전성에 관한 연구 (Studies on Antimicrobial Activities and Safety of Natural Naringin in Korea)

  • 한성순;유일준
    • 한국균학회지
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    • 제16권1호
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    • pp.33-40
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    • 1988
  • 시판 감귤의 과피에서 naringin을 분리하고 가수분해하여 얻은 naringenin의 항균시험을 실시한 바 세균에서 naringin은 gram 양성균보다 gram 음성균이 비교적 강한 항균력을 나타내었으나 naringenin은 그 반대 현상을 나타내었다. 또 naringin과 naringenin의 항균력을 비교하면 전체적으로 naringenin이 매우 강한 항균작용이 있다. 안전성 시험에서 $LD_{50}$은 1650 mg/ kg이고 헐액임상화학적 검사에서 대조군과 비교하여 아무런 이상을 발견할 수 없었으며 병리조직학적 검사에서의 현미경 관찰에서도 대조군과 같았으며 투여군에 대해 조직학적 병변이 나타나지 않았으므로 안전성이 없다고 사료된다.

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Duplex PCR을 이용한 토끼(Oryctolagus cuniculus)와 고양이(Felis catus) 육류의 동시 검출법 개발 (Development of Duplex PCR Method for Simultaneous Detection of Rabbit (Oryctolagus cuniculus) and Cat (Felis catus) Meats)

  • 홍연;김미주;양승민;유인숙;김해영
    • Journal of Applied Biological Chemistry
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    • 제58권4호
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    • pp.383-387
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    • 2015
  • 국내 유통 식품 수입 식품 중 토끼와 고양이 고기의 혼입 여부를 알아내고 불법 도축된 고양이 고기를 토끼 고기나 다른 고기로 속여 판매하는 것을 방지하기 위해 토끼와 고양이를 동시에 검출할 수 있는 polymerase chain reaction (PCR) 법을 개발하였다. 토끼와 고양이의 종 특이 프라이머는 미토콘드리아의 cytochrome b 유전자를 대상으로 하였고 개발된 프라이머를 가공식품에 활용하는 것을 고려하여 PCR 산물의 크기는 토끼 101 bp, 고양이 191 bp로 최소화 하였다. 프라이머의 특이성은 총 21종의 동물을 대상으로 검토하였다. 개발된 검출법의 검출 한계는 시료 DNA를 희석하여 PCR과 Bioanalyzer로 확인한 결과 토끼는 0.005 ng, 고양이는 0.0005 ng이었다.

Streptomyces sp. 가 생산하는 항진균성 항생물질에 관한 연구 (제4보) Tetraene계 항진균성 항생물질의 생성및 그의 성장 (Studies on the Antifungal Antibiotics Produced by a Streptomyces sp. (Part 4) The Occurrence of Tetraene Substance and Its Physiological Properties)

  • 고영희;배무
    • 한국미생물·생명공학회지
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    • 제10권3호
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    • pp.211-215
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    • 1982
  • Streptomyces griseorubiginosus var. soyoensis 에 의하여 두가지의 항진균성 항생물질이 생성되었는데 하나는 trans-cinnamamide 이었고 다른 하나는 UV, IR, NMR, mass spectrum 및 화학반응의 결과로 새로운 tetraene계 화합물임이 밝혀져 이 물질을 Tetraene KM-A라 하였다. 본 물질의 항균성을 조사한 결과 곰팡이 및 효모류에 대하여는 강한 항진균성을 나타내었으나 항세균성은 없었다. 배지에 sterol류를 첨가하였을때 Tetraene KM-A의 항균력이 없어지는 것으로 보아 stesoid와 결함함을 알수 있고 항균작용도 이와 관련이 있는 것으로 판단하였다. Tetraene KM-A의 mouse 및 rat에 대한 복강주사에 의한 $LD_{50}$ 은 각각 84.3과 90.4mg/kg이였으며 mouse에 대만 경구독성은 1503mg/kg이었다.

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Identification of Heterodera glycines (Tylenchida; Heteroderidae) Using qPCR

  • Ko, Hyoung-Rai;Kang, Heonil;Park, Eun-Hyoung;Kim, Eun-Hwa;Lee, Jae-Kook
    • The Plant Pathology Journal
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    • 제35권6호
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    • pp.654-661
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    • 2019
  • The soybean cyst nematode, Heterodera glycines, is a major plant-parasitic nematode that has caused important economic losses to Korea's soybean production. Four species of cyst nematodes, H. schachtii, H. glycines, H. trifolii, and H. sojae, all belong to schachtii group are coexist in field soil in Korea. The rapid identification of the nematode is crucial for preventing crop damage and in decision making for controlling this nematode. This study aimed to develop a species-specific primer set for quantitative PCR (qPCR) assay of H. glycines. The specific primer set (HGF1 and HGR1) for H. glycines was designed based on the cytochrome c oxidase subunit I (COI) sequence of mitochondrial DNA. After optimization, it is possible to identify the H. glycines using a qPCR assay with DNA extracted from a single cyst and single second-stage juvenile (J2). The specificity was confirmed by the absence of SYBR fluorescent signals of three other Heterodera species. A serial dilution of DNA extracted from a single cyst was obtained for the sensitivity test. The result showed that the standard curve of the test had a highly significant linearity between DNA concentration and Ct value (R2 = 0.996, slope = -3.49) and that the detection limit concentration of DNA of the primer set was 10 pg of DNA per reaction. Our findings suggested that H. glycines could be distinguished from H. sojae and other Heterodera species when a qPCR assay is used with a specific primer set.

무화과(Fig) 분리 성분의 항균성 규명 및 무화과 비누 제조에 관한 연구 (A Study on the Elucidation of Antimicrobial Activity of Separated Fig Component and the Preparation of Fig Soap)

  • 류성렬
    • 한국응용과학기술학회지
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    • 제32권4호
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    • pp.669-684
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    • 2015
  • 본 연구는 웰빙(well-being)으로 각광받고 있는 천연물 관련 연구에 무화과 추출물의 활용 가능성을 확인하고자 다음의 연구를 수행하였다. 무화과를 세척 건조하여 알코올추출 방법으로 추출한 후, Column chromatography, G-Mass, IR, $^1H$-nmr 방법에 의하여 무화과 추출물의 이화학적 성질을 분석하였으며, 무화과 추출물을 두피 제품에 적용하기 위하여 항균, 항진균에 대한 항균성을 조사하였다. 무화과 추출물의 이화학적 분석은 열매와 잎으로 나누어 분석하였으며, 두 부분 모두 비듬과 피부병 치료 효능을 가진 항균 및 항진균 효능이 있음을 알 수 있었다. 또한 무화과 추출물에 대한 항균성은 액체배지 희석법에 의해 분석하였다. 그리고 소비자의 구매 욕구를 충족시키고, 무화과의 산업화 타당성을 검토하기 위하여 무화과 추출물 함유 수제 투명 및 고형 비누를 제조하여 타당성을 검토하였다.

북한강 수계 대규모 탁수사상 발생에 의한 댐 저수지의 탁수 영향 분석 (Analyzing the Effect of an Extreme Turbidity Flow Event on the Dam Reservoirs in North Han River Basin)

  • 박형석;정세웅;정선아
    • 한국물환경학회지
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    • 제33권3호
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    • pp.282-290
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    • 2017
  • A long-term resuspension of small particles, called persistent turbidity, is one of the most important water quality concerns in the dam reservoirs system located in North Han River. Persistent turbidity may incur aesthetic nuisance and harmful effect on the ecosystem health, in addition to elevated water treatment costs for the drinking water supply to the Seoul metropolitan area. These sufferings have been more intensified as the strength and frequency of rainfall events increase by climate change in the basin. This study was to analyze the effect of an extreme turbidity flow event that occurred in 2006 on the serial reservoirs system (Soyang-Uiam-Cheongpyung-Paldang) in North Han River. The CE-QUAL-W2 model was set up and calibrated for the river and reservoirs system using the field data obtained in 2006 and 2007. The results showed that Soyang Reservoir released turbid water, which was classified as the TSS concentration is greater than 25 mg/L, for 334 days with peak TSS of 264.1 mg/L after the extreme flood event (592.7 mm) occurred between July 10 and 18 of 2006. The turbid water departed from Soyang Reservoir reached at the most downstream Paldang Reservoir after about 20 days and sustained for 41 days, which was validated with water treatment plant data. Since the released water from Soyang Reservoir had low water temperature and high TSS, an underflow formed in the downstream reservoirs and vertically mixed at Paldang Reservoir due to dilution by the sufficient inflow from South Han River.

Isolation and Characterization of Fungal Diversity from Crop Field Soils of Nigeria

  • Yadav, Dil Raj;Kim, Sang Woo;Adhikari, Mahesh;Babu, Anam Giridhar;Um, Yong Hyun;Gim, Eun Bi;Yang, Jae Seok;Lee, Hyug Goo;Lee, Youn Su
    • 한국균학회소식:학술대회논문집
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    • 한국균학회 2014년도 추계학술대회 및 정기총회
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    • pp.49-49
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    • 2014
  • In order to find indigenous beneficial fungal species from crop field soils of Nigeria, 23 soil samples were collected from various places of Nigeria in June, 2013 and fungi were isolated through serial dilution technique. Isolated fungi were purified and differentiated according to their morphological and microscopic characteristics. In total, 38 different representative isolates were recovered and the genomic DNA of each isolates was extracted using QIAGEN$^{(R)}$ Plasmid Mini Kit (QIAGEN Sciences, USA) and the identification of fungi was carried out by sequence analysis of internal transcribed spacer (ITS) region of the 18S ribosomal DNA (18S rDNA). Recovered isolates belonged to 9 fungal genera comprising Fusarium, Aspergillus, Chaetomium, Coniothyrium, Dipodascaceae, Myrothecium, Neosartorya, Penicillium and Trichoderma. Aspergillus spp., Penicillium spp. and Trichoderma spp. were the most dominant taxa in this study. The antagonistic potentiality of species belonged to Trichoderma against 10 phytopathogenic fungi (F. oxysporum, C. gloesporoides, P. cytrophthora, A. alternata, A. solani, S. rolfsii, F. solani, R. solani, S. sclerotiorum and P. nicotiana) was assessed in vitro using dual culture assay. The dual culture assay results showed varied degree of antagonism against the tested phytopathogens. The potential Trichoderma spp. will be further evaluated for their antagonistic and plant growth promotion potentiality under in vivo conditions.

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중합효소연쇄반응(PCR)을 이용한 고양이 혈액내에서의 Toxoplasma gondii 검출에 관한 연구 (Polymerase chain reaction for the detection of Toxoplasma gondii in the blood of cats)

  • 서명득;주보현
    • 대한수의학회지
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    • 제39권6호
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    • pp.1151-1160
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    • 1999
  • This study was conducted to detect the toxoplasma-specific DNA in peripheral blood collected from cats experimentally infected with Toxoplasma gondii (RH strain) and from domiciled cats by B1 gene-base polymerise chain reaction(PCR). The sensitivity of oligonucleotide primer, T-1 & T-2, designed from toxoplasma B1 gene amplification method was compared with parasite detection by mouse inoculation(MI). And also, latex agglutination test(LAT) and indirect fluorescent antibody test(IFAT) were conducted to detect the fluctuation of serum antibodies compared with the detection of toxoplasma by PCR and MI. Toxoplasma B1 gene PCR was shown consistently high sensitivity and the results obtained by PCR agreed completely with those from MI. All blood samples collected before infection with T gondii gave negative results by PCR and MI. Also, toxoplasma Bl gene PCR was not cross reaction with Neospora caninum DNA and normal cat leucocyte as controls. The toxoplasma-specific DNA was detected by PCR in blood of 5 cats experimentally infected with T gondii 6 days after infection and the detection of this specific-DNA was long lasted in blood for 64 days after infection. The detection of toxoplasma-specific DNA by PCR could be identified as few as 10 tachyzoites and the isolation of T gondii by MI could be isolated as few as 1 tachyzoite from tenfold serial dilution of T gondii with normal cat blood, respectively. In healthy domiciled cats, the toxoplasma-specific DNA and the parasite were detected and isolated in blood from 3 of 56(5.3%) cats by both PCR and MI, respectively. In the results of antibody test from the total 56 heads of healthy domiciled cats, the positive rates are 15(26.7%) by LAT and 19(33.9%) by IFAT. These results suggest that PCR detection of toxoplasma can be applied as a sensitive and specific diagnostic and research tool.

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항암 화학요법중인 급성 골수성 백혈병 환자의 구강내 세균변화에 관한 연구 (Changes in the Oral Microflora in Patients with Acute Myeloid Leukemia during the Period of Induction Therapy)

  • Byul-Hee Lee;Chong-Youl Kim
    • Journal of Oral Medicine and Pain
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    • 제18권1호
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    • pp.73-82
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    • 1993
  • To investigate the changes in aerobic and facultative anaerobic oral microflora during remission-induction chemotherapy in patients with acute myeloid leukemia, 10 consecutive patients were studied during a period of 28 days. One day before, during and after the induction therapy, patients were given 10% Betadine solution for mouthrinses after breakfast and kept from eating and drinking. After 3 hours, paraffin-stimulated whole saliva was obtained for 2 minutes and transported to the laboratory. The samples were dispersed and homogenized by use of vortex mixer for 20 seconds. From these samples 10-fold serial dilutions (from 10-1 through 10-3) were prepared. Each dilution of 0.1 ml was plated on duplicate set of one nonselective medium (Blood agar) and four selective media (Sabourauds dextrose agar, Mannitol salt agar, Mac-Conkey agar, SF medium ) using applicator woods. All agar plate were incubated at 37$^{\circ}C$ for 48 hours. The total number of microorganisms was calculated and the percentage distribution of the various microorganisms from each specimen was drawn. 1. The salivary flow rate decreased by 66%, going from 5.38 ml/2min to 1.81 ml/2min over two days during the chemotherapy. 2. The total number of microorganisms in saliva increased by 22%, going from 4.88$\times$105/ml to 6.00$\times$105/ml over two days during the chemotherapy. 3. The salivary flow rate and the total number of microorganisms in saliva were recovered within 28 days after the chemotherapy. 4. The quantitative alteration in oral Enterobacteria, Enterococci, Staphylococci, Cndida during the chemotherapy had no statistical significance. 5. In saliva of the patients with acute myeloid leukemia who ahd intraoral ulcer, Enterobacteria was quantitatively predominent. Our study suggests that chemotherapy-induced transient xerostomia may induce acute oral infection. Consequently, the use of saliva substitute, the removal of intraoral infection source and the consistent oral hygiene care seem to be required to avoid the transmission of potential pathogenes in this group of patients.

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