Hücre Dışı Polimerik Maddeler

Hücre dışı polimerik maddeler (HPM), mikroorganizmalar tarafından salgılanan, hücre parçalanmasından üretilenyüksek moleküler ağırlıklı kompleks bir polimer karışımından ve atıksudan adsorbe edilen organik maddelerdenoluşmaktadır. HPM’nin başlıca bileşenleri (karbonhidratlar, proteinler, hümik maddeler ve nükleik asitler) vekarakteristikleri (adsorpsiyon, biyolojik parçalanabilirlik ve hidrofiliklik/hidrofobiklik) mikrobiyal agregalarınözelliklerini önemli ölçüde etkilemektedir. HPM, çok kompleks özelliklere sahip olduğundan biyolojik atıksuarıtma tesislerindeki rollerini tam olarak anlamak için çok çalışma yapılması gerekmektedir. Bu çalışmada;HPM’nin bileşenleri ve dağılımı, HPM’nin karakteristikleri, HPM üretimine etki eden faktörler, HPMekstraksiyonu, HPM analiz yöntemleri, mikrobiyal agregalarda HPM’nin rolü başlıkları altında HPM ayrıntılıolarak verilmiştir.

Extracellular Polymeric Substances

Extracellular polymeric substances (EPS) are a complex high-molecular-weight mixture of polymers excreted by microorganisms, produced from cell lysis and adsorbed organic matter from wastewater. Their characteristics (e.g., adsorption abilities, biodegradability and hydrophilicity/hydrophobicity) and the contents of the main components (e.g., carbohydrates, proteins, humic substances and nucleic acids) in EPS are found to crucially affect the properties of microbial aggregates. However, as EPS are very complex, much work is still required to fully understand their precise roles in the biological treatment process. A review concerning the composition and distribution, characterization, factors influencing production, extraction of EPS, analysis methods of EPS and role of EPS in microbial aggregates is given in this paper.

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