Volume 39 Issue 3

August 2011


Dear readers of the Hacettepe Journal of Biology and Chemistry,

All known matter is composed of chemical elements or of compounds made from those elements. Humankind’s understanding of our world is grounded in our knowledge of chemistry. Indeed all living processes are controlled by chemical reactions. 

Autoimmune Diseases and Immunoadsorption Therapy

The human immune system is structured to recognize, respond to, and destroy a wide variety of potentially harmful microorganisms. One major component of this defense system depends on its ability to recognize foreign antigens versus healthy cells or tissues. When the immune system begins to destroy vital cells and organs within the body, the resulting reaction can be the basis for certain autoimmune diseases. Immunoadsorption, an extracorporeal technique for the removal of autoantibodies from patient plasma, offers some advantages over plasmapheresis. Immunoadsorption appeared relatively rapid and safe for the extensive removal of pathogenic antibodies and immune-complexes. During the mid 1970’s the first application of therapeutic intervention with immunoadsorbents was reported. In this review, some selected applications on immunoadsorption therapies mainly for removal of anti-dsDNA antibodies from systemic lupus erythematosus (SLE) and rheumatoid factors from rheumatoid arthritis patients plasmas are briefly discussed. 

213 - 229
New Trends in Electrochemical Protein Sensors

Proteins are essential parts of organisms and participate in every process within cells. Protein biosensors are becoming more essential for the through and systematic investigation of complex biological processes. Several methods have been used for development of protein biosensors e.g., surface plasmon resonance, quartz crystal microbalance, chemiluminescence, electrophoresis, fluorescence techniques and electrochemical methods. There has been growing interest for electrochemical metods in protein research (like protein-protein interactions, or some diseases related to proteins investigations). Herein, this paper will specifically focus on new trends in electrochemical protein sensors. 

231 - 239
Cross-Linked Glucose Oxidase Aggregates: Synthesis and Characterization

The aim of the submitted study is to realize carrier-free immobilization (as cross-linking enzyme aggregates) of Aspergillus niger Glucose Oxidase enzyme, to determinate the optimum immobilization conditions, and to investigate the properties of immobilized enzyme sets. Carrier-free enzyme immobilization was realised by forming cross-linked glucose oxidase enzyme aggregates (CLEA’s). Different precipitants were used in different media conditions during forming CLEA’s. The “immobilized enzyme activity” was measured by activity determination method with the use of glucose substrate. The optimum conditions which were determined in the light of the experiments for the cross-linked enzyme aggregates can be summarized as; the initial enzyme concentration, 0.05 mg/ml; the optimum temperature, 25ºC; the precipitant type, BSA; the precipitant concentration, 5 mg/ml; the concentration of glutaraldehyde, 2% (v/v). After determining the optimum conditions, glucose solutions at different concentrations (1.0-4.0 mg/dl) were prepared for investigating the performance of the glucose oxidase aggregates. The kinetic parameters were calculated by Lineweaver-Burk plots such as; Km =0.0115 mM; Vm =1.206 mM.min-1 for native enzyme and Km = 0.025 mM; Vm =0.593 mM.min-1 for cross-linking enzyme aggregates. 

241 - 251
Examining Leaf and Soil Micro Element Contents of Organic Cherry Orchards around Kemalpaşa (İzmir)

In this study, the micro element content of leaf and soil samples of organic and integrated gardens where Salihli and Sapıkısa types of Kemalpaşa region were investigated. Soil analysis of organic gardens, iron (Fe) content is determined medium and sufficient in most part the gardens and generally sufficient in integrated gardens; zinc (Zn) element is low in organic gardens, high in integrated gardens. Copper (Cu) and manganese (Mn) is found in high amounts in all gardens. In both production methods, it has been found that Zn which is a leaf food element is found much lower than the value it should have, Cu sufficient, Fe and Mn in lower amount. Relations between the findings have been examined, the data of them have been evaluated. 

253 - 256
Adsorption of Lead on to Poly(acrylamide- maleic acid)-Based Hydrogel Composites

In this study, adsorptive features of the hydrogel (PAA-MA) and composites (PAA-MA-B and PAA-MA-Z) were investigated for lead (Pb2+). Adsorption of lead on hydrogels and composites is studied by batch adsorption tecnique at 25ºC. In the experiments of the adsorption, the classical Lagmuir, Freundlich and Dubinin-Radushkevich (DR) models sorption models were fitted to the results. Isotherms were L and H type of Giles classification and evaluated with reference to Langmuir, Freundlich and Dubinin-Radushkevich (DR) models. PAA-MA-B had higher adsorption capacity than PAA-MA-Z for lead ion. To increase the adsorption capacity of Pb2+ ion preparing the PAA- MA hydrogel. It has also been observed with increasing B and Z content Pb2+ ion adsorption. The values of enthalpy and entropy changed were positive for lead ions for PAA-MA, PAA-MA-B and PAA-MA-Z. The negative free enthalpy change value indicated that the adsorption process is spontaneous in the sequence of PAA-MA > PAA-MA-B > PAA- MA-Z. Free energy values derived from DR model implied that the sorption process is the ion exchange. The reus- ability tests for Pb2+ for five uses proved that the composites were reusable after complete recovery of the loaded. 

257 - 264
Systematic Studies on Male Genital Organs of Central Anatolian Elateridae (Coleoptera) Species Part II: The Subfamilies Agrypninae, Cardiophorinae, Dendrometrinae and Negastriinae

In this study, male genital organs of Central Anatolian species of the subfamilies Agrypninae, Cardiophorinae, Dendrometrinae and Negastriinae (Elateridae, Coleoptera) are examined. Morphologies of male genital organs are drawn and described in detail. Systematical status of species are discussed due to their male genital organ morphologies. 

265 - 281
Immobilization of Lipase and Lipase Producing Yeast, Yarrowia lipolytica NBRC 1658 ​

Lipase production was screened out of three Yarrowia strains and a novel Candida tropicalis strain isolated from soil samples and Yarrowia lipolytica NBRC 1658 showed the highest lipolytic activity was selected. Lipase produced by Yarrowia lipolytica NBRC 1658 was partially purified by ammonium sulfate precipitation and dialysis. Crude lipase, partially purified lipase and the yeast Yarrowia lipolytica NBRC 1658 was used for immobilization. Immobilization was carried out on carriers such as Sodium-alginate, k-Carrageenan and Agar- Agar. The highest lipase activity was detected in unimmobilized purified lipase sample as 11.17 U/ml. 

283 - 288
Investigation of Radiopharmaceutical Potential of an Unsymmetrical Perylene diimide (DMANPER) Radiolabeled with 131I ​

The aim of this study was to investigate the radiopharmaceutical potential of N-(2,6-diisopropylphenyl)-N’- [4-(N,N-dimethylaminophenyl)]-perylene-3,4,9,10-tetra carboxylic diimide (DMANPER) radiolabeled with 131I using scintigraphic imaging and biodistributional techniques. Radiolabeled DMANPER (131I-DMANPER) was intravenously injected into an adult male Albino rabbit via its ear vein anesthetizing with a mixture of Alfazyne and Alfamine (Serva) to determine dynamic and static situations of radiolabeled compound in the rabbit metabolism. Three rats were used for biodistribution studies corresponding to different time intervals. The animals were sacrificed by heart puncture under ether anesthesia within post-injection time intervals ranging from 30 to 300 min. Results were expressed as % of the injected dose per gram tissue (% ID/g). TLRC analysis showed that DMANPER was successfully radioiodinated with 131I with a yield of practically 100 %. According to scintigraphy studies, 131I-DMANPER was completely accumulated in the stomach in 30 min. In the biodistributional data for 131I-DMANPER in rats, a significant amount of activity is seen in the stomach between 30-60 min. It can be concluded that 131I-DMANPER may be an alternative imaging agent like N-(2,6- diisopropylphenyl)-N`-(4-pyridyl)-perylene-3,4,9,10-tetracarboxylic diimide (PYPER) to be a potential agent for diagnosis and perhaps therapy of stomach cancer. 

289 - 296
Antibacterial Agent Loaded Fungal Polymer for Use As A Wound Dressing

This study is mainly concerned with the preparation and characterization of a novel wound dressing, in the form of three-dimensional microporous structure, from extracellular polysaccharide produced by Trametes versicolor, a white-rot basidiomycete. A model antibiotic (i.e., ciprofloxacin) was loaded into these wound dressings in the preparation procedure. The prepared wound dressings were investigated and evaluated in four main sections. In the first part, morphological evaluations were made by using scanning electron microscopy and the obtained images revealed that the wound dressings were having highly porous structure with interconnected pores. Antibacterial agent loaded-wound dressings were also investigated with swelling behavior, in vitro drug release and biodegradation studies. Obtained results showed that wound dressings from fungal polymer including antibacterial agent could provide a great potential in the treatment of dermal wounds as a new kind of wound dressing material. 

297 - 303
Laccase Production with Submerged and Solid State Fermentation: Benefit and Cost Analysis

The aim of this study is to investigate benefit and cost analysis of enzyme production with solid state and sub- merged fermentation techniques, biotechnological processes within production of value-added products. The approach of benefit and cost analysis is commonly used a way at deciding and investigating of the project.

This analysis was referred two methodologies on production of laccase, a significant enzyme at environmental biotechnology. According to the result of the comparison, benefit/cost ratio in laccase activity obtained with solid state fermentation was calculated 1.76 and the ratio of laccase activity was 22.62 U ml-1, whereas those of submerged fermentation was 2.42 and the activity was 29.08 U ml-1. In particular, induced liquid culture ob- tained submerged fermentation is seen maximum benefit of production facilities and the minimum cost. This situation indicates laccase production with this type fermentation for a company is more attractive. 

305 - 313
  • ISSN 1303 5002
  • © 1973-2024 Hacettepe University