Abstract: A lacto-N-triose II crystal form A and a preparation method therefor. The powder X-ray diffraction pattern of the crystal form has characteristic diffraction peaks at diffraction angles (2?±0.2°) of 4.80, 8.32, 9.62, 12.72, 18.67, 19.90, 21.05, and 21.59 degrees. The lacto-N-triose II crystal form A has good moisture absorption resistance and stability, can reduce packaging costs, and prolongs product shelf life.

Abstract: An ?-salidroside, a method for preparing same, and application thereof. A novel type of salidroside, namely, ?-salidroside, which when compared with the known ?-salidroside, ?-salidroside exhibits superior activity in scavenging DPPH radicals and hydroxyl radicals and can be added as a new functional ingredient to cosmetics or anti-fatigue health supplements. The method for preparing ?-salidroside involves using inexpensive starch, etc., as a glycosyl donor and tyrosol as a substrate, synthesizing ?-salidroside under the action of glycosyltransferase. The glycosyltransferase has strict specificity and chiral catalytic ability, enabling the specific generation of ?-salidroside.

Abstract: The technical field of preparation of organic compounds, and particularly to yeasts producing tyrosol or hydroxytyrosol and construction methods thereof. PcAAS and ADH-encoding DNA sequences are introduced into the yeast strain BY4741, to obtain a PcAAS-ADH recombinant yeast producing tyrosol. A PDC1 knockout cassette and a TyrA expression cassette are introduced into the PcAAS-ADH recombinant yeast to obtain a PcAAS-ADH-?PDC1-TyrA recombinant yeast producing tyrosol. A HpaBC encoding DNA sequence is introduced into the PcAAS-ADH-?PDC1-TyrA recombinant yeast, to obtain a PcAAS-ADH-HpaBC-?PDC1-TyrA recombinant yeast producing hydroxytyrosol. The construction of a tyrosol or hydroxytyrosol biosynthesis pathway in the yeast strain BY4741 enhances the production of tyrosol or hydroxytyrosol.

Abstract: A method for synthesizing lacto-N-biose and belongs to the technical field of bioengineering and oligosaccharide synthesis. A multi-enzyme catalytic system with good biological safety and wide application, and an ATP regeneration cycle system is introduced into a multi-enzyme reaction system, so that the synthesis of lacto-N-biose and the utilization rate of substrates are improved. A novel lacto-N-biose synthetic route lays a foundation for large-scale industrial production of lacto-N-biose and has important economic values and social benefits. At the same time, the synthetic method is efficient, mild, simple, easy to operate, low in cost and suitable for industrial production, and has a high practical application value.

Abstract: The technical field of preparation of organic compounds, and particularly to yeasts producing tyrosol or hydroxytyrosol and construction methods thereof. PcAAS and ADH-encoding DNA sequences are introduced into the yeast strain BY4741, to obtain a PcAAS-ADH recombinant yeast producing tyrosol. A PDC1 knockout cassette and a TyrA expression cassette are introduced into the PcAAS-ADH recombinant yeast to obtain a PcAAS-ADH-?PDC1-TyrA recombinant yeast producing tyrosol. A HpaBC encoding DNA sequence is introduced into the PcAAS-ADH-?PDC1-TyrA recombinant yeast, to obtain a PcAAS-ADH-HpaBC-?PDC1-TyrA recombinant yeast producing hydroxytyrosol. The construction of a tyrosol or hydroxytyrosol biosynthesis pathway in the yeast strain BY4741 enhances the production of tyrosol or hydroxytyrosol.