• 제목/요약/키워드: Biological properties

검색결과 2,877건 처리시간 0.032초

Isolation, Physico-chemical Properties and Biological Activity of Aurodox Group Antibiotics

  • Kim, Si-Kwan;Yeo, Woon-Hyung;Kim, Sang-Seock
    • Journal of Microbiology and Biotechnology
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    • 제6권4호
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    • pp.265-269
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    • 1996
  • An isolate of Streptomyces rochei synonym was found to produce antibiotics with narrow anti-microbial spectrum against Streptococcus and Xanthomonas sp. Among the antibiotic complex produced by the strain, the main active compound was isolated, and its physico-chemical properties and biological activities were investigated. Molecular weight of the compound was determined to be ${[M+H]}^+$ 797 (FAB-MS). UV, $^1H \;and\;^{13}C$ NMR, and IR spectra suggested that the compound is a kirromycin-like aurodox group antibiotic. However, the anti-microbial spectrum of the main compound was slightly different from that of kirromycin. In addition, it was newly found that kirromycin showed a selective anti-microbial activity against Streptococcus pyogenes and phytopathogenic Xanthomonas sp.

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가열과 운동에 의한 생체조직내의 생리적 변화에 따른 광학적 특성의 변화에 관한 연구 (The Effects of Physiological Heating and Exercise on the Optical Properties of Biological Tissue.)

  • 임현수;허웅
    • 대한의용생체공학회:의공학회지
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    • 제14권1호
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    • pp.81-88
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    • 1993
  • This paper is the study of the reflectance of light from biological tissue for red and Infrared wavelengths and relates the acquired reflectance data to expected physiological changes within the skin and muscle layers associated with heat and exercise. The instrument was disigned to collect data from the calf muscle in human subjects with probe located at the surface of skin. Rapid data acquisition method allowed monitoring of rapid changes in reflecttance due to a stimulus. This study demonstrates that changes in O2 saturation and blood fractional volume expected within the dermis and muscle layers were asserted by examining the slopes of the plotted index for heat and exercise. The results presented in thls study support the claim that reflectance can separately discriminate between changes of blood volume and oxygenation in muscle and in skin. The data demonstrate the ability to measure consistent changes In tissue optical properties during exercise and heat.

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Limonene and Its Oxyfunctionalized Compounds: Biotransformation by Microorganisms and Their Role as Functional Bioactive Compounds

  • Junior, Mario Roberto Marostica;Pastore, Glaucia Maria
    • Food Science and Biotechnology
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    • 제18권4호
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    • pp.833-841
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    • 2009
  • Monoterpenes, in special limonene and its derivatives, are well studied in the literature due to their several properties. They are well recognized as major components of essential oils; some of them, are important industry residues, and others present some important biological activities. In this review, the biotransformation of the inexpensive limonene into flavor compounds was briefly reviewed and the main pathways for limonene biotransformation are presented. Furthermore, some important biological properties of these compounds were also considered, like bactericidal activity, induction of immune response, and role in disease prevention, with a little emphasis on some possibilities related to the mechanisms of anticancer action.

A Review of 3D-QSAR in Drug Design

  • Madhavan, Thirumurthy
    • 통합자연과학논문집
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    • 제5권1호
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    • pp.1-5
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    • 2012
  • Quantitative structure-activity relationship (QSAR) methodologies have been applied for many years, to correlate the relationship between physicochemical properties of chemical substances and their biological activities to generate a statistical model for prediction of the activities of new chemical entities. The basic principle behind the QSAR models is that, how structural variation is responsible for the difference in biological activities of the compounds. 3D-QSAR has emerged as a natural extension to the classical Hansch and Free-Wilson approaches, which develops the 3D properties of the ligands to predict their biological activities using various chemometric techniques (PLS, G/PLS, ANN etc). It has served as a valuable predictive tool in the design of pharmaceuticals and agrochemicals. This review seeks to provide different 3D-QSAR approaches involved in drug designing process to develop structure-activity relationships and also discussed the fundamental limitations, as well as those that might be overcome with the improved methodologies.

Carbon Ion Therapy: A Review of an Advanced Technology

  • Kim, Jung-in;Park, Jong Min;Wu, Hong-Gyun
    • 한국의학물리학회지:의학물리
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    • 제31권3호
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    • pp.71-80
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    • 2020
  • This paper provides a brief review of the advanced technologies for carbon ion radiotherapy (CIRT), with a focus on current developments. Compared to photon beam therapy, treatment using heavy ions, especially a carbon beam, has potential advantages due to its physical and biological properties. Carbon ion beams with high linear energy transfer demonstrate high relative biological effectiveness in cell killing, particularly at the Bragg peak. With these unique properties, CIRT allows for accurate targeting and dose escalation for tumors with better sparing of adjacent normal tissues. Recently, the available CIRT technologies included fast pencil beam scanning, superconducting rotating gantry, respiratory motion management, and accurate beam modeling for the treatment planning system. These techniques provide precise treatment, operational efficiency, and patient comfort. Currently, there are 12 CIRT facilities worldwide; with technological improvements, they continue to grow in number. Ongoing technological developments include the use of multiple ion beams, effective beam delivery, accurate biological modeling, and downsizing the facility.

Eriodictyol induces apoptosis via regulating phosphorylation of JNK, ERK, and FAK/AKT in pancreatic cancer cells

  • Oh, Ui Hyeon;Kim, Da-Hye;Lee, Jungwhoi;Han, Song-I;Kim, Jae-Hoon
    • Journal of Applied Biological Chemistry
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    • 제65권2호
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    • pp.83-88
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    • 2022
  • Although it has been intensively studied over the past few decades, pancreatic cancer remains one of the most lethal cancers. Eriodictyol, a plant-derived flavonoid mainly found in citrus fruits, exerts diverse biological effects, including anti-oxidant, anti-cancer, and anti-inflammatory properties. In this study, we investigated the anticancer properties of eriodictyol and its mechanisms of action in pancreatic cancer cells. In both SNU213 and Panc-1 cells, eriodictyol decreased viability, induced apoptosis, and decreased clonogenicity. In addition, eriodictyol treatment increased the phosphorylation level of JNK and decreased the phosphorylation levels of ERK, FAK, and AKT. These observations provide insight into the molecular mechanisms of eriodictyol-induced apoptosis in pancreatic cancer cell lines, and could contribute to the development of candidate compounds for treating pancreatic cancer.

각기 다른 유기물이 투여된 토양에서 토양의 화학적, 미생물학적 특성과 미생물의 다양성에 미치는 생물비료의 효과 (Effects of a Biological Amendment on Chemical and Biological Properties and Microbial Diversity in Soils Receiving Different Organic Amendments)

  • 박기춘;로버트 크레이머
    • 한국토양비료학회지
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    • 제40권4호
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    • pp.234-241
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    • 2007
  • 여러가지의 선발된 미생물로 구성된 미생물비료는 토양 개량과 식물 생장 촉진을 위해서 여러 유기물과 결합하여 이용되기도 한다. 미생물 비료를 미생물 비료 단독으로 그리고 도시 가로수 부산물 퇴비, 가금류 분뇨 부산물, 레드클로버와 귀리의 피복작물 등의 유기물과 같이 토양에 처리하여 토양의 화학적 또는 생물학적 특성에 미치는 효과를 측정하였다. 액체상의 미생물 비료를 2년동안 3회 처리하였다. 미생물 비료 단독으로는 pH, K, 유기물 함량에 영향을 미치지 않았지만, 미생물비료의 처리는 2년 가을 모두 가금류 분뇨 부산물을 처리한 토양의 인산 함량을 증가시켰고, 첫해 가을에 퇴비를 처리한 토양의 칼슘함량을 증가시켰으며, 레드클로버를 처리한 토양의 Ca, Mg, 그리고 양이온교환용량을 감소시켰다. 미생물 비료는 레드클로버가 처리된 토양에서 첫 해 7월에 탈수소효소 활성을 증가시켰다. 미생물 비료는 유기물이 처리되지 않은 토양이나 퇴비가 처리된 토양에서 FDA의 가수분해도를 가끔 증가시켰다. 가금류 분뇨 부산물과 레드 클로버가 처리된 토양의 FDA 가수분해도와 가금류 분뇨 부산물이 처리된 토양의 탈수소효소활성은 미생물 비료의 처리로 감소하였다. 한편, 미생물 비료의 처리는 BIOLOG에 의한 토양 미생물 군락의 생리생태적 다양성에는 영향을 미치지 못했다. 따라서 토양의 미생물학적 특성에 미치는 미생물비료의 효과는 같이 투여되는 유기물의 종류에 따라 다양하다고 할 수 있으며, 탈수소효소의 활성은 레드클로버가 처리된 토양에서, 그리고 FDA 가수분해도는 퇴비와 귀리가 처리된 토양에서 가끔 증가했다.

Cellulose-based Nanocrystals: Sources and Applications via Agricultural Byproducts

  • Seo, Yu-Ri;Kim, Jin-Woo;Hoon, Seonwoo;Kim, Jangho;Chung, Jong Hoon;Lim, Ki-Taek
    • Journal of Biosystems Engineering
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    • 제43권1호
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    • pp.59-71
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    • 2018
  • Purpose: Cellulose nanocrystals (CNCs) are natural polymers that have been promoted as a next generation of new, sustainable materials. CNCs are invaluable as reinforcing materials for composites because they can impart improved mechanical, chemical, and thermal properties and they are biodegradable. The purpose of this review is to provide researchers with information that can assist in the application of CNCs extracted from waste agricultural byproducts (e.g. rice husks, corncobs, pineapple leaves). Methods & Results: This paper presents the unique characteristics of CNCs based on agricultural byproducts, and lists processing methods for manufacturing CNCs from agricultural byproducts. Various mechanical treatments (microfluidization and homogenization) and chemical treatments (alkali treatment, bleaching and hydrolysis) can be performed in order to generate nanocellulose. CNC-based composite properties and various applications are also discussed. Conclusions: CNC-based composites from agricultural byproducts can be combined to meet end-use applications such as sensors, batteries, films, food packaging, and 3D printing by utilizing their properties. The review discusses applications in food engineering, biological engineering, and cellulose-based hydrogels.

Electrochemical Properties of Polyaniline Electrodes Prepared by Chemical Synthesis and Electrodeposition: Revisited with High-Scan-Rate Behaviors

  • Nam, Ji Hyun;Woo, Cho Hyeon;Kim, Kwang Man;Ryu, Kwang Sun;Ko, Jang Myoun
    • Journal of Electrochemical Science and Technology
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    • 제3권2호
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    • pp.80-84
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    • 2012
  • The polyaniline (PANI) electrodes are prepared by chemical synthesis and electrodeposition methods and their supercapacitive properties are characterized and compared by morphology observation, cyclic voltammetry as a function of scan rate, and impedance spectra analysis. In particular, the supercapacitive properties obtained in the range of higher potential scan rates (e.g., over $200mV\;s^{-1}$) are emphasized to be capable of utilizing adequately the high power capability of supercapacitor. As a result, the PANI electrode by the electrodeposition shows superior specific capacitance (max. $474F\;g^{-1}$ at $10mV\;s^{-1}$ and about $390F\;g^{-1}$ at $500mV\;s^{-1}$) than those by the chemical synthesis method. This is mainly due to highly porous structure obtained by the electrodeposition to yield higher specific surface area.

설사증 이환견(罹患犬)으로 부터 분리한 canine parvovirus의 성상에 관한 연구 (Biological and physicochemical properties of canine parvovirus isolated from the dogs with diarrhea)

  • 최해연;전무형;박성국
    • 대한수의학회지
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    • 제31권3호
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    • pp.295-302
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    • 1991
  • From 1988 to 1989, 8 strains of canine parvovirus-2(CPV-2) were isolated from the fecal specimens from the dogs that were clinically diagnosed as canine parvoviral enteritis in the veterinary hospitals located in the regions of Taejeon and Chungbuk province. The biological and physicochemical properties for the isolates were studied. Among 62 fecal samples collected from the dogs with enteric diseases, 24(38.7%) showed the haemagglutinating activity to porcine erythrocyte ranging from 16 to 16,384 of HA titers. In cytopathological studies with CRFK cells, intranuclear inclusion bodies were observed in all of eight specimens with the high HA titer over 1,000, of which three specimens showed cytoplasmic inclusions concurrently with the intranuclear inclusion bodies. It was found that the isolates revealed the highest haemagglutinating activity with porcine erythrocytes and the relatively lower haemagglutination titers with the erythrocytes from cat and rabbit. None of erythrocytes from the other animals reacted with the isolates. By the cross-haemagglutination inhibition test for the isolates with the reference viruses and sera, the isolates were evidently identified as the strains of CPV-2. In physicochemical property test, the isolates were stable in lipid solvent, pH and heat treatment at $56^{\circ}C$ for 30 min, and showed the virus particle size less than 25 nm, containing a DNA genome.

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