Prakash Indra, Bunders Cynthia, Devkota Krishna P, Charan Romila D, Ramirez Catherine, Priedemann Christopher, Markosyan Avetik
The Coca-Cola Company, Atlanta, GA 30313, USA.
AMRI-Albany, Analytical Development, Albany, NY 12212, USA.
Biomolecules. 2014 Mar 31;4(2):374-89. doi: 10.3390/biom4020374.
A minor product, rebaudioside M2 (2), from the bioconversion reaction of rebaudioside A (4) to rebaudioside D (3), was isolated and the complete structure of the novel steviol glycoside was determined. Rebaudioside M2 (2) is considered an isomer of rebaudioside M (1) and contains a relatively rare 1→6 sugar linkage. It was isolated and characterized with NMR (1H, 13C, COSY, HSQC-DEPT, HMBC, 1D-TOCSY, and NOESY) and mass spectral data. Additionally, we emphasize the importance of 1D and 2D NMR techniques when identifying complex steviol glycosides. Numerous NMR spectroscopy studies of rebaudioside M (1), rebaudioside D (3), and mixture of 1 and 3 led to the discovery that SG17 which was previously reported in literature, is a mixture of rebaudioside D (3), rebaudioside M (1), and possibly other related steviol glycosides.
从莱鲍迪苷A（4）生物转化为莱鲍迪苷D（3）的反应中分离出一种次要产物莱鲍迪苷M2（2），并确定了这种新型甜菊醇糖苷的完整结构。莱鲍迪苷M2（2）被认为是莱鲍迪苷M（1）的异构体，含有相对罕见的1→6糖键。通过核磁共振（1H、13C、COSY、HSQC-DEPT、HMBC、1D-TOCSY和NOESY）和质谱数据对其进行了分离和表征。此外，我们强调了一维和二维核磁共振技术在鉴定复杂甜菊醇糖苷时的重要性。对莱鲍迪苷M（1）、莱鲍迪苷D（3）以及1和3的混合物进行的大量核磁共振光谱研究发现，文献中先前报道的SG17是莱鲍迪苷D（3）、莱鲍迪苷M（1）以及可能的其他相关甜菊醇糖苷的混合物。
