©The World Botanical Associates Web Page
Prepared by Richard W. Spjut
Dec 2007

Eysenhardtia texana
Brewster Co., TX
Black Gap Wildlife Management Area
Nov 2007



Alvarez L., M. Y. Rios, C. Esquivel, M. I. ChávezI, G. Delgado, M. I. AguilarI, M. L. Villarreal and V/ Navarro.  Cytotoxic isoflavans from Eysenhardtia polystachya. J. Nat. Prod. 26;61(6):767–770. “Two new cytotoxic isoflavans, (3S)-7-hydroxy-2',3',4',5', 8-pentamethoxyisoflavan (1) and (3S)-3',7-dihydroxy-2',4',5', 8-tetramethoxyisoflavan (2), were isolated from the bark and trunks of Eysenhardtia polystachya (Leguminosae), together with the known constituents stigmasterol, isoduartin, cuneatin, 7-hydroxy-2',4', 5'-trimethoxyisoflavone, and 3,4-dimethoxy-8, 9-(methylenedioxy)pterocarpan. The structures of 1 and 2 were elucidated on the basis of spectroscopic methods. The antimicrobial, cytotoxic, and insecticidal potential of some of these compounds were evaluated. The isoflavans 1, 2, and isoduartin (2', 7-dihydroxy-3',4',8-trimethoxyisoflavan) displayed moderate cytotoxic activity against KB cell lines.

Narváez-Mastache J.M., F. Novillo and G. Delgado.   2007. Antioxidant aryl-prenylcoumarin, flavan-3-ols and flavonoids from Eysenhardtia subcoriacea. Phytochemistry: Sep. “Antioxidant activity (AOA) assay-guided chemical analysis, using a rat pancreas homogenate model, of aerial parts from Eysenhardtia subcoriacea, led to isolation of the new compound subcoriacin (3-(2'-hydroxy-4',5'-methylendioxyphenyl)-6-(3''-hydroxymethyl-4''-hydroxybut-2''-enyl)-7-hydroxycoumarin) together with the known substances: (+)-catechin, (-)-epicatechin, (+)-afzelechin, eriodictyol, (+)-catechin 3-O-beta-d-galactopyranoside and quercetin 3-O-beta-d-galactopyranoside as bioactive constituents. The structure of the compound was determined from 1D and 2D NMR spectroscopic analyses. Additional known constituents were characterized. The bioactive compounds showed also moderate to strong radical scavenging properties against diphenylpicrylhydrazyl radical (DPPH). In addition, subcoriacin, (+)-catechin, (-)-epicatechin and (+)-afzelechin improved the reduced glutathione levels in rat pancreatic homogenate.”

Narváez-Mastache J. M., Soto C, and G. Delgado. 2007. Antioxidant evaluation of Eysenhardtia species (Fabaceae): relay synthesis of 3-O-Acetyl-11alpha,12alpha-epoxy-oleanan-28,13beta-olide isolated from E. platycarpa and its protective effect in experimental diabetes. Biol. Pharm. Bull. 30(8):1503–1510. “The antioxidant activities of plant extracts from Eysenhardtia platycarpa, E. punctata, and E. subcoriacea (Fabaceae) species, used in Mexican traditional medicine for the treatment of diabetes complications, were analyzed in a rat pancreas homogenate model. Methanolic extracts of E. platycarpa, E. punctata, and E. subcoriacea protected the pancreatic homogenate from 2,2-azo-bis(2-amidinopropane)dihydrochloride (AAPH)-induced damage. The inhibitory effect was dose-dependent at concentrations of 10-1000 ppm and correlated with 1,1 diphenyl-2-picrylhydrazyl (DDPH) radical scavenger capacity. 3-O-Acetyl-11alpha,12alpha-epoxy-oleanan-28,13beta-olide (1, EC(50)=21.2+/-2.2 microM), (+)-catechin (2, EC(50)=7.4+/-1.1 microM), and (+)-catechin 3-O-beta-D-galactopyranoside (3, EC(50)=11.5+/-1.5 microM), natural constituents isolated from the branches of E. platycarpa, displayed significant antioxidant activity. Compounds 1 and 2 significantly increased (p<0.001) the pancreatic glutathione (GSH) concentration alone and in combination with AAPH treatment. Compound 1 was obtained from oleanolic acid by relay synthesis via acetylation, bromo-lactonization, dehydrobromination, and oxidation, and its antioxidant effect was evaluated on streptozotocin (STZ)-induced diabetic rats. On its own, 1 at a dose of 100 mg/kg b. wt. (i.p.) for 5 d significantly increased the activities of glutathione peroxidase (GSHPx) and catalase (CAT). Simultaneous treatment of 1 (100 mg/kg b. wt.) and STZ significantly reduced the pancreatic thiobarbituric acid reactive substances (TBARS) concentration together with a significant increase in the activities of GSHPx and CAT, preventing hyperglycemia induced by STZ after 5 d of treatment. The present study demonstrates the antioxidant and antihyperglycemic activities of compound 1 isolated from Eysenhardtia species used in traditional.

Narvaez-Mastache J. M, M. L. Garduńo-Ramírez, L. Alvarez and G. Delgado.  2006. Antihyperglycemic activity and chemical constituents of Eysenhardtia platycarpa. J. Nat. Prod. 69(12):1687–1691.  “The methanolic extracts from branches (BEP) and leaves (LEP) of Eysenhardtia platycarpa significantly decreased the blood glucose levels in normal and streptozotocin (STZ)-induced diabetic rats. One new flavone, (1"R)-5,4',1"-trihydroxy-6,7-(3",3"-dimethylchroman)flavone (1), together with the known compounds 5,7-dihydroxy-6-methyl-8-prenylflavanone (3), 5,7-dihydroxy-8-methyl-6-prenylflavanone (4), 5,7-dihydroxy-6-prenylflavanone (5), 5,7-dihydroxy-8-prenylflavanone (6), 3-O-acetyloleanolic acid (7), oleanolic acid, 3beta-acetoxy-11alpha,12alpha-epoxy-oleanan-28,13beta-olide, lupeol, betulinic acid, beta-sitosterol, beta-sitosteryl beta-D-glucopyranoside, beta-sitosteryl palmitate, and 3-O-methyl-myo-inositol were isolated from BEP. Additionally, one new flavanone, (2S)-4'-O-methyl-6-methyl-8-prenylnaringenin (2), as well as the known compounds 3, 4, 6, 4'-O-methyl-8-prenylnaringenin (8), and 5-hydroxy-7-methoxy-8-prenylflavanone (9) were isolated from LEP. 3-O-Acetyloleanolic acid (7), identified as the major constituent of BEP, showed a significant decrease (31 mg/kg of body weight, P < 0.05) in the glucose level of STZ-induced diabetic rats. The obtained results correlate with the traditional use of this species.

Wächter G. A, J. J. Hoffmann, T. Furbacher, M. E. Blake and B. N. Timmermann. 1999. Antibacterial and antifungal flavanones from Eysenhardtia texana. Phytochemistry 52(8): 1469–1471. “An activity-guided fractionation of a methanol-dichloromethane extract obtained from the aerial parts of Eysenhardtia texana led to the isolation of two novel antibacterial and antifungal flavanones together with a known flavanone. Their structures were established as 4',5,7-trihydroxy-8-methyl-6-(3-methyl-[2-butenyl])-(2S)-flavanone, 4',5,7-trihydroxy-6-methyl-8-(3-methyl-[2-butenyl])-(2S)-flavanone and 4',5-dihydroxy-7-methoxy-6-(3-methyl-[2-butenyl])-(2S)-flavanone on the basis of their UV, 1D and 2D-NMR spectra.