Hayrunnisa Nadaroglu

Bio: Hayrunnisa Nadaroglu is an academic researcher from Atatürk University. The author has contributed to research in topics: Adsorption & Enzyme assay. The author has an hindex of 18, co-authored 107 publications receiving 1084 citations. Previous affiliations of Hayrunnisa Nadaroglu include Florida State University College of Arts and Sciences.

Purification of Chitinase enzymes from Bacillus subtilis bacteria TV-125, investigation of kinetic properties and antifungal activity against Fusarium culmorum.

Abstract: Chitin is the main structural component of cell walls of fungi, exoskeletons of insects and other arthropods and shells of crustaceans. Chitinase enzyme is capable of degrading chitin, and this enzyme can be used as a biological fungicide against phytopathogenic fungi, as well as an insecticide against insect pests. In this study, 158 isolates, which were derived from bacteria cultures isolated from leaves and root rhizospheres of certain plants in Turkey, were selected after confirming that they are not phytopathogenic based on the hypersensitivity test performed on tobacco; and antifungal activity test was performed against Fusarium culmorum, which is a pathogenic fungi that cause decomposition of roots of vegetables. Accordingly, chitinase enzyme activity assay was performed on 31 isolates that have an antifungal activity, and among them the isolate of Bacillus subtilis TV-125 was selected, which has demonstrated the highest activity. Chitinase enzyme was purified by using ammonium sulphate and DEAE-sephadex ion exchange chromatography. Ammonium sulphate precipitation of chitinase enzyme from Bacillus subtilis TV-125 isolate was performed at maximum range of 0-20%, and 28.4-fold purification was obtained with a 13.4% of yield. Optimum activity of the purified enzyme was observed at pH 4.0 and at 50°C of temperature. In addition, it was identified that Bacillus subtilis TV-125A isolate retains 42% of its activity at 80°C temperature. In the last phase of the study, chitinase enzyme purified from Bacillus subtilis TV-125A was tested on four fungal agents, although all the results were positive, it was particularly effective on F. culmorum according to the findings.

Synthesis of Nanoparticles by Green Synthesis Method

Abstract: As an emphasis on the synergistic interaction of nanotechnology and nanobiotechnology, nanoparticles need to develop environmentally benign technologies in the synthesis of bio-synthesis and nanomaterialsMicroorganisms, plants and fungi can be used as biodegradable agent material inthis field work Thus, it was possible to develop a simple, fast and green method for the synthesis of nanoparticles Various strategies are used for the synthesis of nanoparticles Traditionally, physicochemical techniques have increased environmental con-cerns due to the reduction of metal ions followed by surface modification, toxiccompounds added for stability, and dangerous byproducts formed At the time of nanoparticle synthesis by adding chemical and physical methods at high temperature and pressure, reducing and stabilizing agents; nanoparticle synthesis by biological methods; room temperature and pres-sure, reducing and stabilizing agents are needed Green synthesis method; provides a faster metallic nanoparticle production by offering an environmentally friendly, simple, economi-cal and reproducible approach Given the wide range of applications of metallic nanoparticles produced, biological methods play a major role in the synthesis of metallic nanoparticles

Removal of cobalt (II) ions from aqueous solution by using alternative adsorbent industrial red mud waste material

Abstract: This study on the removal of cobalt ions from aqueous solutions by red mud was conducted in batch condition. Its objective was to investigate the possibility of using red mud waste material as an alternative to high cost commercial adsorbent materials for the removal of cobalt from aqueous solution. In this study, batch experiments were carried out for the adsorption of cobalt onto red mud industry waste. The red mud waste material was successfully used for the removal of cobalt ion from aqueous solution and the technique appears industrially applicable and viable. The potential of economically cheap waste materials like red mud was assessed for cobalt adsorption from aqueous solutions. The operating variables studied were contact time, initial solution pH, initial metal concentration, temperature and adsorbent dosage. The experimental investigation results show that activated red mud has a high level of adsorption capacity for cobalt ion. The adsorption data was correlated with the Langmuir and Freundlich isotherm models. It was found out that the Langmuir and Freundlich isotherms fitted well to the data. Consequently, it was concluded that the red mud can be successfully used for the removal of the cobalt ions from the aqueous solutions with heavy metals. Key words: Red mud, cobalt removal, aqueous solution, adsorption isotherms.

A review on biosynthesis of silver nanoparticles and their biocidal properties.

Abstract: Use of silver and silver salts is as old as human civilization but the fabrication of silver nanoparticles (Ag NPs) has only recently been recognized. They have been specifically used in agriculture and medicine as antibacterial, antifungal and antioxidants. It has been demonstrated that Ag NPs arrest the growth and multiplication of many bacteria such as Bacillus cereus, Staphylococcus aureus, Citrobacter koseri, Salmonella typhii, Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumonia, Vibrio parahaemolyticus and fungus Candida albicans by binding Ag/Ag+ with the biomolecules present in the microbial cells. It has been suggested that Ag NPs produce reactive oxygen species and free radicals which cause apoptosis leading to cell death preventing their replication. Since Ag NPs are smaller than the microorganisms, they diffuse into cell and rupture the cell wall which has been shown from SEM and TEM images of the suspension containing nanoparticles and pathogens. It has also been shown that smaller nanoparticles are more toxic than the bigger ones. Ag NPs are also used in packaging to prevent damage of food products by pathogens. The toxicity of Ag NPs is dependent on the size, concentration, pH of the medium and exposure time to pathogens.

Nanotechnology in sustainable agriculture: Present concerns and future aspects

Abstract: Nanotechnology is a promising field of interdisciplinary research. It opens up a wide array of opportunities in various fields like medicine, pharmaceuticals, electronics and agriculture. The potential uses and benefits of nanotechnology are enormous. The current global population is nearly 7 */billion with 50% living in Asia. A large proportion of those living in developing countries face daily food shortages as a result of environmental impacts or political instability, while in the developed world there is surplus of food. For developing countries, the drive is to develop drought and pest resistant crops, which also maximize yield. The potential of nanotechnology to revolutionise the health care, textile, materials, information and communication technology, and energy sectors has been well publicized. The application of nanotechnology to agriculture and food industries is also getting attention nowadays. Investments in agriculture and food nanotechnologies carry increasing weight because their potential benefits range from improved food quality and safety to reduced agricultural inputs and improved processing and nutrition. While most investment is made primarily in developed countries, research advancements provide glimpses of potential applications in agricultural, food, and water safety that could have significant impacts on rural populations in developing countries. This review is concentrated on modern strategies used for the management of water, pesticides, limitations in the use of chemical pesticides and potential of nano-materials in sustainable agriculture management as modern approaches of nanotechnology. Key words: Agriculture, nanotechnology, nanofertilizer, nanoencapsulation, nanoherbicides.

Chitosan nanoparticles preparation and applications

Abstract: Shell fish processing industry is very common in coastal areas. While processing, only the meat is taken, the head and shells are discarded as waste. On an average, the sea food industry produces 80,000 tons of waste per year. The sheer amount of waste makes degradation a slow process causing accumulation of waste over a period of time. A very simple and effective solution to this environmental hazard is the recycling of shell waste to commercially viable products like chitin. Chitosan is the N-acetyl derivative of chitin obtained by N-deacetylation. Chitosan is widely used in food and bioengineering industries for encapsulation of active food ingredients, enzyme immobilization, as a carrier for controlled drug delivery, in agriculture as a plant growth promoter. Chitosan is also a defense elicitor and an antimicrobial agent. Chitosan has interesting properties such as biodegradability, biocompatibility, bioactivity, nontoxicity and polycationic nature. This review presents structural characteristics and physicochemical properties of chitosan. The methods of preparation of chitosan nanoparticles are detailed. Applications of chitosan nanoparticles are discussed. Applications include drug delivery, encapsulation, antimicrobial agent, plant growth-promoting agent and plant protector.