title: Potent in vivo antifungal activity against powdery mildews of pregnane glycosides from the roots of Cynanchum wilfordii.
abstract: Two new pregnane glycosides, kidjoranine 3-O-β-D-glucopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 4)-α-L-cymaropyranosyl-(1 → 4)-β-D-cymaropyranosyl-(1→4)-α-L-diginopyranosyl-(1 → 4)-β-D-cymaropyranoside (5) and caudatin 3-O-β-D-glucopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 4)-α-L-cymaropyranosyl-(1 → 4)-β-D-cymaropyranosyl-(1 → 4)-α-L-diginopyranosyl-(1 → 4)-β-D-cymaropyranoside (6), were isolated from the roots of Cynanchum wilfordii along with four known compounds (1-4). The antifungal activities of the six compounds against barley powdery mildew caused by Blumeria graminis f. sp. hordei were compared to the antifungal activity of polyoxin B. The caudatin glycosides (1, 4, and 6) showed stronger antifungal activities than polyoxin B, whereas kidjoranine glycosides (2, 3, and 5) had weaker activities than polyoxin B. A wettable powder-type formulation (C. wilfordii-WP20) of the ethyl acetate extract from C. wilfordii roots prohibited the development of barley powdery mildew much more effectively than the commercial fungicide polyoxin B-WP10. In addition, C. wilfordii-WP20 effectively controlled strawberry powdery mildew caused by Sphaerotheca humuli under greenhouse conditions. Thus, the crude extract containing the pregnane glycosides can be used as a botanical fungicide for the environmentally benign control of powdery mildews.
authors: Green Chemistry Division, Korea Research Institute of Chemical Technology, Yuseong-Gu, PO Box 107, Daejeon 305-600, Republic of Korea.
authors: Mi-Young
authors: MY
authors: Yoon
authors: Nam Hee
authors: NH
authors: Choi
authors: Byung Sun
authors: BS
authors: Min
authors: Gyung Ja
authors: GJ
authors: Choi
authors: Yong Ho
authors: YH
authors: Choi
authors: Kyoung Soo
authors: KS
authors: Jang
authors: Seong-Sook
authors: SS
authors: Han
authors: Byeongjin
authors: B
authors: Cha
authors: Jin-Cheol
authors: JC
authors: Kim
mesh_terms: D000935:Antifungal Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D001203:Ascomycota / Q000187:drug effects* / Q000502:physiology; D031105:Cynanchum / Q000737:chemistry*; D006027:Glycosides / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D015394:Molecular Structure; D010935:Plant Diseases / Q000382:microbiology*; D010936:Plant Extracts / Q000302:isolation & purification / Q000494:pharmacology*; D018517:Plant Roots / Q000737:chemistry; D011278:Pregnanes / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*
chemical_list: D000935:Antifungal Agents; D006027:Glycosides; D010936:Plant Extracts; D011278:Pregnanes