Biopolymers are polymers synthesized by living organisms. Depending on the monomeric units, biopolymers can be classified as polynucleotides (e.g., DNA and RNA), polypeptides (e.g., protein), polysaccharides (e.g., cellulose) and so on. Biopolymers not only play an essential role in nature, but also have wide applications in various fields of industry...