• Title/Summary/Keyword: Biological properties

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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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    • v.6 no.4
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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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The Effects of Physiological Heating and Exercise on the Optical Properties of Biological Tissue. (가열과 운동에 의한 생체조직내의 생리적 변화에 따른 광학적 특성의 변화에 관한 연구)

  • Lim, Hyun-Soo;Huh, Woong
    • Journal of Biomedical Engineering Research
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    • v.14 no.1
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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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    • v.18 no.4
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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
    • Journal of Integrative Natural Science
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    • v.5 no.1
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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
    • Progress in Medical Physics
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    • v.31 no.3
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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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    • v.65 no.2
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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.

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

  • Park, Kee-Choon;Kremer, Robert J.
    • Korean Journal of Soil Science and Fertilizer
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    • v.40 no.4
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    • pp.234-241
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    • 2007
  • Biological amendments consisting of suspensions of selected microorganisms are often used in conjunction with various organic materials for amending soils to improve soil quality and plant growth. The effects of the biological amendment on chemical and biological properties of soil were investigated for a biological amendmentalone and when combined with different organic materials includingmunicipal compost (MC), poultry litter (PL), and cover crops (red clover (RC) and spring oats). A liquid preparation of a biological amendment called Effective Microorganisms was sprayed on the tested plots three times over a two-year period. Effective Microorganisms alone did not influence pH, K, or organic matter content in soil. However, increases in P in PL-treated soils in fall of both years andCa in MC-treated soil in fall 2001, and decreases in Ca, Mg, and cation exchange capacity (CEC) in RC-planted soil were associated with EM. Increased dehydrogenase(DH) activitiesassociated with Effective Microorganismswere only detected in July (P=0.0222) and October (P=0.0834) for RC-planted soils in the first year. Fluorescein diacetate (FDA) hydrolysisappeared to be enhanced by Effective Microorganisms in soils untreated or treated with MC and oatsbut only sporadically during the sampling period. FDA hydrolysis in both PL- and RC-treated soils as well as DH activity in PL-treated soils decreased with Effective Microorganisms treatment. Effective Microorganisms did not influence substrate utilization patterns expressed by the BIOLOG assay. We conclude that Effective Microorganisms effects on soil chemical and biological properties varied depending on the added organic materials. Effective Microorganisms periodically increased soil DH activity and FDA hydrolysis with RC and with MC plus oats, respectively.

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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    • v.43 no.1
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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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    • v.3 no.2
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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.

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

  • Choi, Hae-yeon;Jun, Moo-hyung;Park, Seong-kuk
    • Korean Journal of Veterinary Research
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    • v.31 no.3
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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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