I J Pemberton | PubMed Health

PubMed1993

Technical note: an improved method for extraction and quantification of toxic phenethylamines from Acacia berlandieri.

N-methyl-beta-phenethylamine (NMPEA) has been previously identified as the toxin causing locomotor ataxia in sheep and goats grazing the browse plant, Acacia berlandieri. We describe a simplified procedure for extraction and quantification of naturally occurring beta-phenethylamines from this Acacia species. Dried, ground plant tissue was extracted (1:20 wt/vol) with 1% glacial acetic acid and filtered. The filtrate was passed through a high-sulfonated polymeric solid-phase extraction (SPE) tube, which retained the compounds of interest (tyramine, hordenine, NMPEA) but allowed many impurities co-extracted from the plant tissue to be washed through. Amines were eluted from the tube, then separated and detected by reversed-phase HPLC. Extracted amines were resolved by HPLC in < 15 min, and UV-absorbance spectra matched those of authentic standards. Recovery efficiency of amine standards (125 micrograms/mL) from SPE tubes averaged 97, 101, and 98% for tyramine, hordenine, and NMPEA, respectively. Excess sample loss was prevented and the large volumes of solvents required for liquid-liquid extraction eliminated by use of solid-phase extraction techniques.

Acacia↗

PubMed1988

In vitro metabolism of formononetin and biochanin A in bovine rumen fluid.

The phyto-estrogens formononetin (7-hydroxy-4'methoxyisoflavone) and biochanin A (5-7-dihydroxy-4'-methoxyisoflavone) were independently incubated in vitro at 39 degrees C in bovine rumen fluid from a fistulated steer receiving an alfalfa hay diet. Formononetin was incubated in studies 1 and 2, whereas biochanin A was incubated in study 3. The isoflavones were separated and quantified by high performance liquid chromatography. In study 1, formononetin concentration, 14.80 micrograms/ml at time 0, declined to 1.16 micrograms/ml by 12 h and to .76 micrograms/ml by 24 h. Daidzein (7,4-dihydroxyisoflavone), .18 micrograms/ml at time 0, peaked at 12.92 micrograms/ml at 6 h and decreased to 1.30 micrograms/ml by 24 h. Equol (7,4'-dihydroxyisoflavan), detected at 6 h, peaked at 16.94 micrograms/ml at 18 h and dropped to 12.64 micrograms/ml at 24 h. In incubation study 2, formononetin declined from 17.57 micrograms/ml at time 0 to 7.08 micrograms/ml by 6 h. Daidzein concentration was 1.75 micrograms/ml at time 0 and increased to 12.03 micrograms/ml by 6 h. Equol was detected at 3 h and increased to 2.32 micrograms/ml at 6 h. The half-lives were 4.3 for formononetin and 9.8 h for daidzein in this in vitro system. In study 3, biochanin A, 8.54 micrograms/ml at time 0, decreased to 0 micrograms/ml by 12 h in incubation 3, whereas genistein (5,7,4'-trihydroxyisoflavone), 3.17 micrograms/ml at 1 h, peaked at 7.35 micrograms/ml at 4 h and decreased to .32 micrograms/ml at 24 h. Equol was not detected in incubation study 3. The half-lives of biochanin A and genistein were 3.9 and 5.5 h, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗