Alpha-Glucosidase Inhibitory Activity of Saponins Isolated from Vernonia gratiosa Hance

• Published in: Journal of microbiology and biotechnology Vol. 33; no. 6; pp. 797 - 805
• Main Authors: Pham Van Cong, Hoang Le Tuan Anh, Le Ba Vinh, Yoo Kyong Han, Nguyen Quang Trung, Bui Quang Minh, Ngo Viet Duc, Tran Minh Ngoc, Nguyen Thi Thu Hien, Hoang Duc Manh, Le Thi Lien, Ki Yong Lee
• Format: Journal Article
• Language: Korean
• Published: 한국미생물생명공학회 30.06.2023
• Subjects: stigmastane-type steroidal glycoside; vernogratiosides A-C; Vernonia gratiosa; α-glucosidase inhibitor; {\alpha}$-glucosidase inhibitor; stigmastane-type steroidal glycoside; vernogratiosides A-C; Vernonia gratiosa
• ISSN: 1017-7825; 1738-8872

Species belonging to the Vernonia (Asteraceae), the largest genus in the tribe Vernonieae (consisting of about 1,000 species), are widely used in food and medicine. These plants are rich sources of bioactive sesquiterpene lactones and steroid saponins, likely including many as yet undiscovered chemical components. A phytochemical investigation resulted in the separation of three new stigmastane-type steroidal saponins (1 - 3), designated as vernogratiosides A-C, from whole plants of V. gratiosa. Their structures were elucidated based on infrared spectroscopy (IR), one-dimensional (1D) and two-dimensional nuclear magnetic resonance (2D NMR), high-resolution electrospray ionization mass spectrometry (HR-ESI-MS), and electronic circular dichroism analyses (ECD), as well as chemical reactivity. Molecular docking analysis of representative saponins with α- glucosidase inhibitory activity was performed. Additionally, the intended substances were tested for their ability to inhibit α-glucosidase activity in a laboratory setting. The results suggested that stigmastane-type steroidal saponins from V. gratiosa are promising candidate antidiabetic agents.