scholarly journals Biological properties of chemically modified insulins. I. Biological activity of proinsulin and insulin modified at A1-glycine and B29-lysine

Diabetologia ◽  
1976 ◽  
Vol 12 (6) ◽  
pp. 601-608 ◽  
Author(s):  
R. H. Jones ◽  
D. I. Dron ◽  
M. J. Ellis ◽  
P. H. S�nksen ◽  
D. Brandenburg
Keyword(s):  
Biological Activity ◽  
Biological Properties ◽  
Chemically Modified ◽  
Chemically Modified Insulins

Biological Function and Chemistry of Endothelin. A Review

1999 ◽  
Vol 64 (8) ◽  
pp. 1211-1252 ◽  
Author(s):  
Jan Hlaváček ◽  
Renáta Marcová
Keyword(s):  
Biological Activity ◽  
Amino Acid ◽  
Biological Function ◽  
Biological Properties ◽  
Structural Basis ◽  
Amino Acid Residues ◽  
Snake Venoms ◽  
Vasoactive Peptides ◽  
Physico Chemical ◽  
Endothelin A

The first part of this review deals with the biosynthesis and a biological function of strongly vasoactive peptides named endothelins (ETs) including vasoactive intestinal contractor. Where it was useful, snake venoms sarafotoxins which are structural endothelin derivatives, were also mentioned. In the second part, an attention is paid to structural basis of the ETs biological activity, with respect to alterations of amino acid residues in the parent peptides modifying the conformation and consequently the physico-chemical and biological properties in corresponding ETs analogs. Special attention is focussed on the area of ETs receptors and their interaction with peptide and non peptide agonists and antagonists, important in designing selective inhibitors of ETs receptors potentially applicable as drugs in a medicine. A review with 182 references.

Aktywność biologiczna ekstraktów z propolisu

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Magdalena Woźniak ◽  
Anna Kwiatkowska ◽  
Elżbieta Hołderna-Kędzia ◽  
Katarzyna Sosnowska ◽  
Lucyna Mrówczyńska ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Biological Activity ◽  
Phenolic Compounds ◽  
Propylene Glycol ◽  
Ethyl Alcohol ◽  
Antiradical Activity ◽  
Colorimetric Method ◽  
Biological Properties ◽  
Bioactive Substances ◽  
Dpph Test

Introduction. Propolis, also known as bee glue, is a resinous material collected by honeybees with numerous biological properties, including antibacterial, antifungal, antioxidant and anticancer effects. Due to its health-promoting properties, propolis is a component of many products, including dietary supplements, cosmetics and healthy food. Aim. The aim of the study was to determine the antibacterial, antifungal and antioxidant activity of propolis extracts, as well as to compare the biological activity of propolis extracts, depending on the solvent used – ethyl alcohol or propylene glycol. Material and methods. Two propolis extracts were used in the research – the first was prepared in ethyl alcohol, and the second in propylene glycol. The antimicrobial activity of the examined extracts was determined against S. aureus, E. coli and C. albicans. The antioxidant activity was determined on the basis of the evaluation of their antiradical activity in the DPPH· test and Fe2+ chelating activity. Moreover, the total content of phenolic compounds and flavonoids in the tested extracts was determined using the colorimetric method. Results. The tested propolis extracts, regardless of the solvent used (ethyl alcohol or propylene glycol), showed high antibacterial (against S. aureus), antifungal (against C. albicans) and antioxidant (antiradical activity in the DPPH· test and ferrous iron chelating potency in the ferrozine test) activity. Moreover, both tested extracts were characterized by a high and similar content of bioactive compounds – phenolic compounds and flavonoids. Conclusions. The results of the conducted tests showed that the solvent used did not affect determined biological activity and the content of bioactive substances in the tested propolis extracts.

scholarly journals Influence of Pollution by Antibiotics on Biological Properties of Soils (Through the Example of Ordinary Chernozem)

2021 ◽  
Author(s):  
Yuliya Akimenko
Keyword(s):  
Biological Activity ◽  
Polyphenol Oxidase ◽  
Catalase Activity ◽  
Direct Relationship ◽  
Negative Impact ◽  
Biological Indicators ◽  
Biological Properties ◽  
Field Conditions ◽  
Ordinary Chernozem ◽  
Biological Parameters

Abstract In model laboratory and field conditions, the influence of pollution by antibiotics (benzylpenicillin, ampicillin, streptomycin, oxytetracycline, tylosin, pharmasin, tromexin, aliseryl, and nystatin) on the biological properties of ordinary chernozem was examined in concentrations of 1-1000 mg/kg. A decrease in the majority of the basic biological parameters of chernozem occurs when the concentration of antibiotics is 100 mg/kg of soil. In most cases, there was a direct relationship between the content of antibiotics in the soil and the scale of a decrease in the studied parameters. The degree of the influence of antibiotics was determined by their nature, concentration and time of exposure. Antibacterial antibiotics had more negative impact on the studied indicators than fungicidal ones. By the degree of inhibiting the biological properties of chernozem, antibiotics formed the following sequence: ampicillin > benzylpenicillin ≥ streptomycin ≥ oxytetracycline > tylosin ≥ pharmasin > nystatin > tromexin > aliseryl. Among the examined biological parameters when polluted by antibiotics, the most informative one was the number of ammonifying bacteria and the activity of dehydrogenases. The least informative was the indicator of catalase activity. The abundance of bacteria of the genus Azotobacter in case of pollution by antibiotics was not informative. The degree of a decrease in biological indicators was more pronounced in laboratory conditions than in the field ones. The rate of the biological activity recovery of chernozem after pollution in the field was 2 times higher. According to the degree of resistance to antibiotics, the investigated microorganisms of chernozem formed the following sequence: bacteria of the genus Azotobacter > micromycetes > amylolytic bacteria > ammonifying bacteria. Enzymes formed the following sequence: peroxidase ≥ polyphenol oxidase > catalase > dehydrogenase > invertase ≥ phosphatase. Antibiotics had prolonged influence on the biological properties of ordinary chernozem. The examined parameters were observed not to be recovered to control values even on the 120th day after the pollution.

Processing, secretion, and biological properties of a novel growth factor of the fibroblast growth factor family with oncogenic potential

1988 ◽  
Vol 8 (7) ◽  
pp. 2933-2941
Author(s):  
P Delli-Bovi ◽  
A M Curatola ◽  
K M Newman ◽  
Y Sato ◽  
D Moscatelli ◽  
...  
Keyword(s):  
Biological Activity ◽  
Growth Factor ◽  
Kaposi Sarcoma ◽  
Biological Properties ◽  
Fibroblast Growth ◽  
Serum Free Medium ◽  
Free Medium ◽  
Serum Free ◽  
The Stability ◽  
Nih 3T3

We recently reported that the protein encoded in a novel human oncogene isolated from Kaposi sarcoma DNA was a growth factor with significant homology to basic and acidic fibroblast growth factors (FGFs). To study the properties of this growth factor (referred to as K-FGF) and the mechanism by which the K-fgf oncogene transforms cells, we have studied the production and processing of K-FGF in COS-1 cells transfected with a plasmid encoding the K-fgf cDNA. The results show that, unlike basic and acidic FGFs, the K-FGF protein is cleaved after a signal peptide, glycosylated, and efficiently secreted as a mature protein of 176 or 175 amino acids. Inhibition of glycosylation impaired secretion, and the stability of the secreted K-FGF was greatly enhanced by the presence of heparin in the cultured medium. We have used the conditioned medium from transfected COS-1 cells to test K-FGF biological activity. Similar to basic FGF, the K-FGF protein was mitogenic for fibroblasts and endothelial cells and induced the growth of NIH 3T3 mouse cells in serum-free medium. Accordingly, K-fgf-transformed NIH 3T3 cells grew in serum-free medium, consistent with an autocrine mechanism of growth. We have also expressed the protein encoded in the K-fgf protooncogene in COS-1 cells, and it was indistinguishable in its molecular weight, glycosylation, secretion, and biological activity from K-FGF. Taken together, these results suggest that the mechanism of activation of this oncogene is due to overexpression rather than to mutations in the coding sequences.

scholarly journals Structural Analysis of Fucoidans

2008 ◽  
Vol 3 (10) ◽  
pp. 1934578X0800301 ◽  
Author(s):  
Maria I. Bilan ◽  
Anatolii I. Usov
Keyword(s):  
Biological Activity ◽  
Structural Analysis ◽  
Charge Density ◽  
Brown Algae ◽  
Uronic Acid ◽  
Chemical Structure ◽  
Biological Activities ◽  
Biological Properties ◽  
Sulfated Polysaccharides ◽  
New Information

Sulfated polysaccharides of brown algae (“fucoidans”) constitute a wide variety of biopolymers from simple sulfated fucans up to complex heteropolysaccharides composed of several neutral monosaccharides, uronic acid and sulfate. The increased interest in this class of polysaccharides is explained by their high and versatile biological activities, and hence, by their possible use in new drug design. Structural analysis of several fucoidans demonstrates that their biological properties are determined not only by charge density, but also by fine chemical structure, although distinct correlations between structure and biological activity cannot be formulated at present. The aim of this review is to describe the methods of structural analysis currently used in fucoidan chemistry, and to discuss some new information on the structures of fucoidans presented in recent publications.

In vitro biological properties and predicted DNA–BSA interaction of three new dicyanidoargentate(i)-based complexes: synthesis and characterization

2018 ◽  
Vol 42 (6) ◽  
pp. 4679-4692 ◽  
Author(s):  
Ahmet Karadağ ◽  
Nesrin Korkmaz ◽  
Ali Aydın ◽  
Şaban Tekin ◽  
Yusuf Yanar ◽  
...  
Keyword(s):  
Biological Activity ◽  
Biological Properties ◽  
Synthesis And Characterization ◽  
Drug Candidates ◽  
Bsa Interaction

The synthesis, characterization and biological activity of three novel dicyanidoargentate(i)-based complexes are reported. The in vitro results show that these complexes may be potent antiproliferative drug candidates.

scholarly journals MECHANOCHEMICAL ACTIVATION OF PHARMACEUTICAL SUBSTANCES AS A FACTOR FOR MODIFICATION OF THEIR PHYSICAL, CHEMICAL AND BIOLOGICAL PROPERTIES

2019 ◽  
pp. 118-123 ◽  
Author(s):  
A.V. SYROESHKIN ◽  
E.V. USPENSKAYA ◽  
T.V. PLETENEVA ◽  
M.A. MOROZOVA ◽  
T.V. MAKSIMOVA ◽  
...  
Keyword(s):  
Biological Activity ◽  
Chemical Elements ◽  
Raw Materials ◽  
Biological Activities ◽  
Biological Properties ◽  
Raw Material ◽  
Native Form ◽  
Preparation Methods ◽  
Pharmaceutical Substances ◽  
Before And After

Objective: Study the influence of the mechanical preparation methods (grinding, fluidization) of solid pharmaceutical substances (PS) and herbal raw material on their physicochemical properties and biological activities. Methods: Test substances and solvents-Lactose monohydrate (DFE Pharma, Germany). Sodium chloride, bendazol hydrochloride (all Sigma-Aldrich, USA) and herbal raw material (Callisia fragrans). The dispersity and native structure of pharmaceutical substances were analyzed by several methods: optical microscopy–Altami BIO 2 microscope (Russia); low angle laser light scattering (LALLS) method (Malvern Instruments, UK); Spirotox method–Quasichemical kinetic of cell transition of cellular biosensor Spirostomum ambiguum; Fourier-transform infrared spectroscopy–the analysis in the middle IR region was carried out using an IR Cary 630 Fourier spectrometer (Agilent Technologies, USA). The analysis of dried leaves of C. fragrans before and after mechanical activation was performed using Shimadzu EDX-7000 X-ray fluorescence spectrophotometer without mineralization (Shimadzu, Japan). Results: It was established that the mechanical change, such as dispersion and drying, alters the biological activity of PS and herbal raw materials. The observed increase in the influence of the dispersed substance on the biosensor S. ambiguum is quantitatively estimated from the values of the activation energy (obsEa), which turns to be valued 1,5 (P≤0,05) times more than for the native form substance. In the study of the dependence of the availability of chemical elements K, Ca, Zn on the degree of dispersion of herbal raw materials was established a quantitative 4-fold (P≤0,05) increase in the concentration of elements in mechano-activated raw materials. Conclusion: By the example of the biological model of Spirotox (single-celled biosensor S. ambiguum) and herbal raw materials obtained from C. fragrans, the increase of biological activity of PS at the dispersion of initial preparations was proved.

scholarly journals Enzyme Immobilization on Maghemite Nanoparticles with Improved Catalytic Activity: An Electrochemical Study for Xanthine

Materials ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1776 ◽  
Author(s):  
Massimiliano Magro ◽  
Davide Baratella ◽  
Andrea Venerando ◽  
Giulia Nalotto ◽  
Caroline R. Basso ◽  
...  
Keyword(s):  
Biological Activity ◽  
Catalytic Activity ◽  
Enzyme Immobilization ◽  
Self Assembly ◽  
Immobilized Enzymes ◽  
Biological Properties ◽  
Oxide Nanoparticles ◽  
Electrochemical Studies ◽  
Maghemite Nanoparticles ◽  
Surface Active

Generally, enzyme immobilization on nanoparticles leads to nano-conjugates presenting partially preserved, or even absent, biological properties. Notwithstanding, recent research demonstrated that the coupling to nanomaterials can improve the activity of immobilized enzymes. Herein, xanthine oxidase (XO) was immobilized by self-assembly on peculiar naked iron oxide nanoparticles (surface active maghemite nanoparticles, SAMNs). The catalytic activity of the nanostructured conjugate (SAMN@XO) was assessed by optical spectroscopy and compared to the parent enzyme. SAMN@XO revealed improved catalytic features with respect to the parent enzyme and was applied for the electrochemical studies of xanthine. The present example supports the nascent knowledge concerning protein conjugation to nanoparticle as a means for the modulation of biological activity.

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