The present invention relates to 5-O-[6-(3-hydroxy-3-methyl glutarate)-D-glucoside as a new antioxidant.

The present invention relates to 5-O-[6-(3-hydroxy-3-methyl glutarate)-D-glucoside as a new antioxidant.

The present document describes a method for extracting anthocyanin derivatives from a plant source. The method comprises the step of separating a homogenized extract of plant source in a polar acidified solvent for obtaining a residual solid, and a filtrate mixed with the acidified polar solvent. The separation includes a coarse filtration done by centrifugation of the plant source extract, by a filtration with a first filter having a pore size of about 100 m, and a fine filtration is done using a second filter having a pore size of about 10 m. Then, the filtrate mixed with the acidified polar solvent is evaporated for substantially separating the acidified polar solvent from the filtrate to obtain a semi-solid extract of anthocyanin derivatives.

The present document describes a method for extracting anthocyanin derivatives from a plant source. The method comprises the step of separating a homogenized extract of plant source in a polar acidified solvent for obtaining a residual solid, and a filtrate mixed with the acidified polar solvent. The separation includes a coarse filtration done by centrifugation of the plant source extract, by a filtration with a first filter having a pore size of about 100 m, and a fine filtration is done using a second filter having a pore size of about 10 m. Then, the filtrate mixed with the acidified polar solvent is evaporated for substantially separating the acidified polar solvent from the filtrate to obtain a semi-solid extract of anthocyanin derivatives.

A novel kaempferol compound is disclosed. The novel kaempferol compound is obtained by enzymatically treating kaempferol saccharides extracted from Camellia oleifera seed cake, which is discarded after oil extraction from camellia seeds, and a skin protection composition containing the same that is safe for the human body. The enzyme-treated-kaempferol compound has an increased molecular weight as sugar is additionally linked to the precursor kaempferol saccharide, and can exhibit a skin protection effect.

Provided is a method for producing a protected glycoside derivative, including reacting a sugar in which all hydroxyl groups of the sugar are protected by protective groups and protective groups of a hydroxyl group at a 1-position and a hydroxyl group at a 2-position are acyl groups, with a phenolic compound in the presence of at least one catalyst selected from the group consisting of trifluoromethanesulfonic acid and copper (II) trifluoromethanesulfonate, in which the phenolic compound is bonded to an anomeric position of the sugar and other hydroxyl groups of the sugar are protected.

Provided is a method for producing a protected glycoside derivative, including reacting a sugar in which all hydroxyl groups of the sugar are protected by protective groups and protective groups of a hydroxyl group at a 1-position and a hydroxyl group at a 2-position are acyl groups, with a phenolic compound in the presence of at least one catalyst selected from the group consisting of trifluoromethanesulfonic acid and copper (II) trifluoromethanesulfonate, in which the phenolic compound is bonded to an anomeric position of the sugar and other hydroxyl groups of the sugar are protected.

Provided is method for producing a glycoside in which a phenolic compound is bonded to an anomeric position of a sugar, the method including: a step (1) of reacting a peracetylated sugar with the phenolic compound in the presence of an acid catalyst; and a step (2) of directly adding a deacetylating agent and a deacetylating solvent selected from the group consisting of water and an alcohol to a reaction mixture obtained in the step (1) to perform a deacetylation reaction.

Provided is method for producing a glycoside in which a phenolic compound is bonded to an anomeric position of a sugar, the method including: a step (1) of reacting a peracetylated sugar with the phenolic compound in the presence of an acid catalyst; and a step (2) of directly adding a deacetylating agent and a deacetylating solvent selected from the group consisting of water and an alcohol to a reaction mixture obtained in the step (1) to perform a deacetylation reaction.