Mete Yilmaz

Bursa Teknik Üniversitesi · Bioengineering

Concerning human and environmental health, safe alternatives to synthetic pesticides are urgently needed. Many of the currently used synthetic pesticides are not authorized for application in organic agriculture. In addition, the developed resistances of various pests against classical pesticides necessitate the urgent demand for efficient and safe...

An increasing human population necessitates more food production, yet current techniques in agriculture, such as chemical pesticide use, have negative impacts on the ecosystems and strong public opposition. Alternatives to synthetic pesticides should be safe for humans, the environment , and be sustainable. Extremely diverse ecological niches and m...

To determine the drivers of phytoplankton biomass, we collected standardized morphometric, physical, and biological data in 230 lakes across the Mediterranean, Continental, and Boreal climatic zones of the European continent. Multilinear regression models tested on this snapshot of mostly eutrophic lakes (median total phosphorus [TP] = 0.06 and tot...

The cyanotoxin microcystin (MC) is a secondary metabolite, synthesized by nonribosomal peptide synthetase (NRPS) and polyketide synthase (PKS) enzymes. It has many isoforms and the mechanism of its diversity is not well understood. One of the MC synthetase genes, mcyA, codes for the McyA module containing two adenylation (A) domains. The first doma...

Microalgae present a massive and untapped natural source of biomass for various applications. The fresh-water microalgae biomass was collected from Lake Uluabat in Turkey. Diatoms, which contain large amounts of SiO2 in the form of cell walls, constituted 60% wt. of the biomass. SiO2/N-doped carbon nanocomposite (SiO2/NC) was obtained by an efficie...

Routine monitoring of microalgal growth requires the use of one of several methods such as cell counting under the microscope and measuring optical density (OD) with a spectrophotometer. Each of these methods has their advantages and disadvantages. For example, counting cells under the microscope can be time consuming, but it provides the best esti...

Exopolysaccharides (EPS), important metabolites of microalgae and cyanobacteria, can be used as food additives, drug active substances, and in detergents, adhesives and waste water treatment processes. Cyanobacterial EPSs are divided into two groups: the first group includes EPSs which are associated with the cell membrane (capsular, sheath); while...

Exopolysaccharides (EPS), important metabolites of microalgae and cyanobacteria, can be used as food additives, drug active substances, and in detergents, adhesives and waste water treatment processes. Cyanobacterial EPSs are divided into two groups: the first group includes EPSs which are associated with the cell membrane (capsular, sheath); while...

Microcystins (MCs) are hepatotoxic and potentially carcinogenic cyanotoxins. They exhibit high structural variability, with nearly 250 variants described to date. This variability can result in incomplete detection of MC variants during lake surveys due to the frequent use of targeted analytical methods and a lack of standards available for identif...

Under ongoing climate change and increasing anthropogenic activity, which continuously challenge ecosystem resilience, an in-depth understanding of ecological processes is urgently needed. Lakes, as providers of numerous ecosystem services, face multiple stressors that threaten their functioning. Harmful cyanobacterial blooms are a persistent probl...

Insight into how environmental change determines the production and distribution of cyanobacterial toxins is necessary for risk assessment. Management guidelines currently focus on hepatotoxins (microcystins). Increasing attention is given to other classes, such as neurotoxins (e.g., anatoxin-a) and cytotoxins (e.g., cylindrospermopsin) due to thei...

Insight into how environmental change determines the production and distribution ofcyanobacterial toxins is necessary for risk assessment. Management guidelines currently focus onhepatotoxins (microcystins). Increasing attention is given to other classes, such as neurotoxins (e.g.,anatoxin-a) and cytotoxins (e.g., cylindrospermopsin) due to their p...

Harmful Algal Bloom species are ubiquitous and their blooms occur in the Arabian Gulf. In this study, two cruises were performed in 2012 and 2013 to collect phytoplankton samples from 4 sites in the Arabian Gulf. Toxin analyses of phytoplankton samples for 32 algal toxins from 5 different toxin groups were conducted on the samples using both enzyme...

Harmful algae bloom (HAB) is a natural phenomenon that occurs due to increase of algae cell density in water column that subsequently causes deleterious effects to natural environments as well as mankind. HABs in the Qatari waters occurred when a particular group of Phytoplankton cells proliferate in the eutrophied semi-enclosed water body. In this...

A major consequence of the sustained degradation of the coastal environment is the progressive eutrophication, which makes Harmful Algal Blooms (e.g. cyanobacteria) more likely to happen and with potential production of cyanotoxins which may create health hazards. Qatar concerns have been rising following the observations of blooms in the last year...

The St. Lucie Estuary, located on the southeast coast of Florida, provides an example of a subtropical ecosystem where seasonal changes in temperature are modest, but summer storms alter rainfall regimes and external inputs to the estuary from the watershed and Atlantic Ocean. The focus of this study was the response of the phytoplankton community...

Cylindrospermopsis raciborskii is a potentially toxic cyanobacterium which has become increasingly prominent in algal blooms throughout the USA. Twenty strains of C. raciborskii isolated from Florida, and one strain from Indiana (USA), were tested for the ability to produce three toxins, cylindrospermopsin, microcystin and saxitoxin using newly dev...

Aphanizomenon ovalisporum is the only confirmed cylindrospermopsin producer identified in the United States to date. On the other hand, Cylindrospermopsis raciborskii is a prominent feature of many lakes in Florida and other regions of the United States. To see the variation in cylindrospermopsin cyrB gene adenylation domain sequences and possibly...

One of the most common and widespread bloom-forming cyanobacteria associated with toxin production is Microcystis aeruginosa (Kutzing) Lemmerman. While normally associated with fresh water environments, this toxigenic species has been observed at bloom concentrations in a number of major estuaries worldwide. This study examined the effect of salini...

Cyanobacteria, red algae, and cryptomonad algae utilize phycobilin chromophores that are attached to phycobiliproteins to harvest solar energy. Heme oxygenase (HO) in these organisms catalyzes the first step in phycobilin formation through the conversion of heme to biliverdin IXalpha, CO, and iron. The Synechocystis sp. PCC 6803 genome contains two...

DNA isolated from environmental samples often contains enzyme inhibitors disruptive to downstream molecular applications. Most of the existing methods of cyanobacterial DNA isolation do not effectively eliminate these inhibitors from sediment samples or cells collected from freshwater ecosystems. We describe improved methods based on the xanthogena...

The toxin cylindrospermopsin (CYN) is produced by a variety of cyanobacterial genera. One of these, Cylindrospermopsis raciborskii, is generally assumed to be the source of CYN in lakes and rivers in Florida, USA. However, in this study, none of the eight Florida isolates of this species tested contained the genetic determinants involved in toxin p...