Abstract: The disclosure discloses a method for efficient biosynthesis of Reb D by glycosyltransferase, belonging to the field of biocatalytic synthesis. According to the disclosure, a glycosyltransferase having an activity to catalyze synthesis of Reb D from Reb A is obtained, and a mutant YojK-I241T/G327N with high catalytic activity is obtained through directed evolution. The glycosyltransferase mutant YojK-I241T/G327N and a sucrose synthase AtSuSy derived from Arabidopsis thaliana are used for constructing a coupling reaction to realize efficient catalytic synthesis of Reb D with Reb A as a substrate. The reaction is carried out by using 19.32 g/L (20 mmol/L) of Reb A as the substrate for 15 h to efficiently synthesize 20.59 g/L of Reb D, and the yield of Reb D reaches 91.29%, which provides an efficient and green new pathway for production of Reb D.

Abstract: The present disclosure discloses preparation and application of a novel multifunctional nanocomposite material with new photosensitizer, and belongs to the technical field of photodynamic therapy and the field of biomedicine. The photosensitizer multifunctional nanocomposite material provided by the present disclosure is prepared by self-assembly of cercosporin and an acid-sensitive copolymer multifunctional material with liver tumor cell targeting ability and traceability, wherein the acid-sensitive copolymer multifunctional material can be a copolymer of poly(N,N-dimethylaminoethyl methacrylate) and poly-3-azido-2-hydroxypropyl methacrylate covalently linked by galactose-modified rhodamine B.

Abstract: The present disclosure discloses preparation and application of a novel multifunctional nanocomposite material with new photosensitizer, and belongs to the technical field of photodynamic therapy and the field of biomedicine. The photosensitizer multifunctional nanocomposite material provided by the present disclosure is prepared by self-assembly of cercosporin and an acid-sensitive copolymer multifunctional material with liver tumor cell targeting ability and traceability, wherein the acid-sensitive copolymer multifunctional material can be a copolymer of poly(N,N-dimethylaminoethyl methacrylate) and poly-3-azido-2-hydroxypropyl methacrylate covalently linked by galactose-modified rhodamine B.