- Further study on the 1,4-alpha-transglucosylation of rubusoside, a sweet steviol-bisglucoside from Rubus suavissimus.
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Rubusoside (the beta-D-glucosyl ester of 13-O-beta-D-glucosyl-steviol), which is the major sweet principle of leaves of Rubus suavissimus S. Lee, was subjected to 1,4-alpha-transglucosylation by the cyclodextringlucanotransferase-starch system (the CGTase system). The tri- and tetra-glucosylated products were isolated together with the mono- and di-glucosylated products, which had already been isolated. A prominent increase in intensity of the sweetness was observed for the compounds which were di- and tri-glucosylated at the 13-O-glucosyl moiety. This result further substantiated the structure-sweetness relationship for 1,4-alpha-glucosylated compounds of steviol-glycosides reported previously. For protection of the 19-COO-glucosyl moiety against glucosylation by the CGTase system, the 4-hydroxyl group of the 19-COO-glucosyl moiety was beta-galactosylated by the beta-galactosidase-lactose system. This galactosylated compound was subjected to a regio-selective glucosylation of the 13-O-glucosyl moiety by the CGTase system, which was followed by enzymic elimination of the galactosyl group to furnish an exclusive preparation of the improved sweeteners just mentioned.
- Ohtani,Aikawa,Ishikawa,Kasai,Kitahata,Mizutani,Doi,Nakaura,Tanaka
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- NATURAL AND SYNTHETIC DITERPENE GLYCOSIDES, COMPOSITIONS AND METHODS
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Novel diterpene glycosides isolated from Stevia extract as well as diterpene glycosides that are synthetically prepared are provided herein. Compositions and consumables comprising the novel diterpene glycosides are also provided herein. Methods of enhancing the sweetness and/or flavor of consumables using the novel diterpene glycosides, methods of preparing compositions and consumables comprising the novel diterpene glycosides, methods of purifying the novel diterpene glycosides and methods of synthesizing the diterpene glycosides are also provided.
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Page/Page column 99; 108-109; 124-125
(2019/08/12)
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- Glucosyltransferase Capable of Catalyzing the Last Step in Neoandrographolide Biosynthesis
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ApUGT, a diterpene glycosyltransferase from Andrographis paniculata, could transfer a glucose to the C-19 hydroxyl moiety of andrograpanin to form neoandrographolide. This glycosyltransferase has a broad substrate scope, and it can glycosylate 26 natural and unnatural compounds of different structural types. This study provides a basis for exploring the glycosylation mechanism of ent-labdane-type diterpenes and plays an important role in diversifying the structures used in drug discovery.
- Li, Yuan,Lin, Hui-Xin,Wang, Jian,Yang, Jian,Lai, Chang-Jiang-Sheng,Wang, Xing,Ma, Bao-Wei,Tang, Jin-Fu,Li, Yong,Li, Xin-Lin,Guo, Juan,Gao, Wei,Huang, Lu-Qi
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supporting information
p. 5999 - 6002
(2018/10/20)
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- Discovery of: Arabidopsis UGT73C1 as a steviol-catalyzing UDP-glycosyltransferase with chemical probes
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Chemoselective and affinity-based probes of steviol were applied to the discovery of glycosyltransferase activity and corresponding UDP-glycosyltransferase in Arabidopsis thaliana, which illustrates a simple strategy for rapidly harnessing minable novel biological parts from plants for synthetic biology.
- Zhou, Yiqing,Li, Weichao,You, Wenjing,Di, Zhengao,Wang, Mingli,Zhou, Haiyan,Yuan, Shuguang,Wong, Nai-Kei,Xiao, Youli
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supporting information
p. 7179 - 7182
(2018/07/03)
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- PRODUCTION OF STEVIOL GLYCOSIDES IN RECOMBINANT HOSTS
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The invention relates to recombinant microorganisms and methods for producing steviol glycosides, glycosylated ent-kaurenol, and glycosylated ent-kaurenoic acid.
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Paragraph 0052; 00202
(2016/08/23)
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- Enzymic Transglucosylation of Rubusoside and the Structure-Sweetness Relationship of Steviol-Bisglycosides
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Rubusoside, the β-D-glucosyl ester of 13-O-β-D-glucosyl-steviol which was isolated from leaves of Rubus suavissimus collected in China as the major sweet principle (yield: 5.4percent), was subjected to α-1 4 transglucosylation with the cyclodextrin glucosyltransferase produced by Bacillus megaterium Strain No. 5 using soluble starch as donor.A significant improvement in the quality of sweetness was observed for the crude reaction mixture, which was separated into mono-, di-, tri-, tetra-, penta-, and hexa-glucosylated products.All isomers of the mono- and di-glucosylated products were further separated.Evaluation of the sweetness of these products compared with stevioside, rebaudioside A, etc. disclosed that the ratio of the number of glucose units at the 13-hydroxyl group to that at 19-carboxyl group seems to have a significant relationship with the sweetness as well as the quality of taste for glucosides of this type.
- Darise, Muchsin,Mizutani, Kenji,Kasai, Ryoji,Tanaka, Osamu,Kitahata, Sumio,et al.
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p. 2483 - 2488
(2007/10/02)
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