A method for producing an inositol derivative includes a step of reacting inositol and dextrin in the presence of cyclodextrin glucanotransferase to generate an inositol derivative in which a sugar is bonded to the inositol, and to obtain a solution containing the inositol derivative and the cyclodextrin glucanotransferase; and a step of removing the cyclodextrin glucanotransferase in the solution using an ultrafiltration membrane, in which a deactivation treatment of the cyclodextrin glucanotransferase in the solution is not performed.

The present invention discloses a mutant of cyclodextrin glycosyltransferase and belongs to the fields of gene engineering and enzyme engineering. According to the present invention, a mutant having higher disproportionation activity of cyclodextrin glycosyltransferase is obtained by mutating the cyclodextrin glycosyltransferase. The disproportionation activity of enzymes of mutants V6D, S90G, T168A, T171A, T383A, G608A and V6D/S90G/T168A/T171A/T383A/G608A is respectively 1.89 times, 1.21 times, 1.21 times, 1.22 times, 1.32 times, 2.03 times and 3.16 times that of the wild enzyme in shake flask fermentations. The present invention has certain significance for the industrial production of cyclodextrin glycosyltransferase, and improves the application potential of the enzyme in food, medicine and chemical industries.

Glucosyl Stevia compositions are prepared from steviol glycosides of Stevia rebaudiana Bertoni. The glucosylation was performed by cyclodextrin glucanotransferase using the starch as source of glucose residues. The glucosyl Stevia compositions were purified to >95% content of total steviol glycosides. The compositions can be used as sweetness enhancers, flavors, flavor enhancers and sweeteners in foods, beverages, cosmetics and pharmaceuticals.

A method of preparing a glucosylated steviol glycoside composition involving by treating stevia materials with cyclodextrin glycosyltransferase.

The invention relates to novel substance mixtures which can be used as aroma compositions to enhance the sweet taste of oral preparations.

Ent-kaurenoic acid glycoside precursor compositions and synthesis methods are provided. The KA-19-monoside, KA-19-bioside and KA-19-trioside precursors can be used as starting materials for a variety of kaurenoic acid based reactions. The precursors provide alternative synthesis pathways for steviol glycosides to the natural pathway based on Steviol biosynthesis. The alternative synthesis pathways using the precursors also circumvent the rate limiting step of the natural Steviol biosynthesis pathway. The precursors can be used individually or in combination to produce a mixture or individual steviol glycosides such as Rebaudioside A, Rebaudioside D or Rebaudioside M. Control over the precursor quantities and composition allows control over the composition of the resulting steviol glycosides that are finally produced.

The present disclosure discloses a maltooligosyl trehalose synthase mutant with improved thermal stability, and belongs to the technical fields of enzyme engineering and protein engineering. The residual enzyme activities of the MTSase mutants S361R, S444E, S361R/S444E, S361K/S444E, G415P/S361R/S444E and G415P consistent with the present disclosure after treatment at 60 C. for 10 min are respectively 70.3%, 50.1%, 83.5%, 65.9%, 100% and 80.7%, which are respectively 1.6, 1.1, 1.9, 1.5, 2.3 and 1.9 times of that of the wild type. The half-lives of the S361R/S444E and G415P/S361R/S444E at 60 C. are respectively 14.9 min and 90.8 min which are respectively 3.2 and 19.7 times of that of the wild type, indicating that the thermal stability of the MTSase mutant consistent with the present disclosure is significantly improved than that of the wild type.

Processes for the preparation of glycosylated steviol glycoside compositions useful sweeteners and flavor modifiers in food and beverage products and the like are improved by the use of basic conditions before, during and/or after an enzyme-catalyzed glycosylation of a steviol glycoside composition.

Glucosyl Stevia compositions are prepared from steviol glycosides of Stevia rebaudiana Bertoni. The glucosylation was performed by cyclodextrin glucanotransferase using the starch as source of glucose residues. The glucosyl Stevia compositions were purified to >95% content of total steviol glycosides. The compositions can be used as sweetness enhancers, flavors, flavor enhancers and sweeteners in foods, beverages, cosmetics and pharmaceuticals.

Glucosyl stevia compositions are prepared from steviol glycosides of Stevia rebaudiana Bertoni. The glucosylation was performed by cyclodextrin glucanotransferase using the starch as source of glucose residues. The glucosyl stevia compositions were purified to >95% content of total steviol glycosides. The compositions can be used as sweetness enhancers, flavors, flavor enhancers and sweeteners in foods, beverages, cosmetics and pharmaceuticals.