Polysaccharides, constitution from lipids

It is estimated that nearly 30 g of dry mixed sludge (from aerobic and anaerobic treatment) are produced per day per inhabitant [53] in municipal treatment systems alone. This suggests that for a city of 1 million inhabitants, this constitutes approximately 30 tonnes of dry sludge produced every day. Wastewater biosolids can be an important source of carbon-based compounds [54], The most important components of wastewater biomass are polysaccharides and proteins, either in pure form or in associations with other compounds, such as glycoproteins, lipopolysaccharides, lipoproteins, and so on. Other constituents include humic substances, deoxyribonucleic acid (DNA), lipids and uronic acids [54]. In the case of lipids, the content of lipids can vary from 2 to 30% [55]. 

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