title: High efficiency transformation of stevioside into a single mono-glycosylated product using a cyclodextrin glucanotransferase from Paenibacillus sp. CGMCC 5316.
abstract: Stevioside is a non-caloric, natural, high-intensity sweetener. However, the bitter aftertaste of stevioside restricts its utilization for human consumption and limits its application in the food industry. In this study, a high efficiency enzymatic modification system was investigated to improve stevioside taste quality. A cyclodextrin glucanotransferase (CGTase) producing strain Paenibacillus sp. CGMCC 5316 was isolated from Stevia planting soil. With starch as glycosyl donor, this CGTase can transform stevioside into a single specific product which is an isomer of rebaudioside A and identified as mono-glycosylated stevioside. The taste of stevioside is improved noticeably by generating mono-glycosylated stevioside, which possesses a sucrose-like taste and has sweetness increased significantly by 35.4%. Next, the parameters influencing CGTase production were optimized. Compared to initial conditions, CGTase activity increased by 214.7% under optimum conditions of 3.9 g/L starch, 17.9 g/L tryptone, and 67.6 h of culture time, and the transglycosylation rate of stevioside was remarkably increased by 284.8%, reaching 85.6%. This CGTase modification system provides a promising solution for improving the sweetness and taste quality of stevioside. The efficiency of CGTase transformation can be greatly increased by optimizing the culture conditions of Paenibacillus sp. CGMCC 5316.
authors.affiliation: State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China.
authors.forename: Xuejian
authors.initials: X
authors.lastname: Yu
authors.affiliation: State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China.
authors.forename: Jinshui
authors.initials: J
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China.
authors.forename: Baozhen
authors.initials: B
authors.lastname: Li
authors.affiliation: State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China. hlyuan@cau.edu.cn.
authors.forename: Hongli
authors.initials: H
authors.lastname: Yuan
mesh_terms: D002851:Chromatography, High Pressure Liquid; D045786:Diterpenes, Kaurane / Q000737:chemistry / Q000378:metabolism*; D005960:Glucosides / Q000737:chemistry / Q000378:metabolism*; D005964:Glucosyltransferases / Q000096:biosynthesis / Q000378:metabolism*; D006031:Glycosylation; D013058:Mass Spectrometry; D056507:Paenibacillus / Q000201:enzymology* / Q000302:isolation & purification / Q000378:metabolism; D013213:Starch / Q000737:chemistry / Q000378:metabolism; D013549:Sweetening Agents / Q000737:chemistry / Q000378:metabolism
chemical_list: D045786:Diterpenes, Kaurane; D005960:Glucosides; D013549:Sweetening Agents; C012043:stevioside; D013213:Starch; C025474:rebaudioside A; D005964:Glucosyltransferases; C019963:cyclomaltodextrin glucanotransferase
keywords: Cyclodextrin glucanotransferase; Enzymatic modification; Rebaudioside A; Stevioside; Transglycosylation