Stimulation of p-nitrophenylphosphatase activity of mung bean shoot extracts. Preliminary observations as a possible screening test for anticonvulsant drugs.
The p-nitrophenylphosphatase (pNPPase) activity of mung bean shoot extracts has similar characteristics to that of animal tissue. Mung bean shoot pNPPase activity is maximal between pH 7.8 and 8.2 and at a substrate concentration between 10 and 20 mM and is inhibited by sodium ions. Mung bean shoot pNPPase activity is competitively inhibited by ATP with a Ki value of 2.8 mM. A wide range of anticonvulsant drugs tested all stimulated the pNPPase activity of the mung bean shoot extracts. The nonanticonvulsant drugs tested did not have this effect, with the exception of pemoline, which, although not acknowledged to be an anticonvulsant drug, did show anticonvulsant activity when tested using conventional methods involving animals. In double-blind trials, 12 out of 15 compounds were correctly classified as anticonvulsants or nonanticonvulsants. It is proposed that the pNPPase activity of mung bean shoot extracts may be useful as a preliminary screen for anticonvulsant drugs.
D009597:4-Nitrophenylphosphatase / Q000378:metabolism*; D000927:Anticonvulsants / Q000494:pharmacology; D004311:Double-Blind Method; D004353:Drug Evaluation, Preclinical; D007887:Fabaceae / Q000201:enzymology*; D006863:Hydrogen-Ion Concentration; D066298:In Vitro Techniques; D010744:Phosphoric Monoester Hydrolases / Q000378:metabolism*; D010936:Plant Extracts / Q000378:metabolism; D010946:Plants, Medicinal
D000927:Anticonvulsants; D010936:Plant Extracts; D010744:Phosphoric Monoester Hydrolases; D009597:4-Nitrophenylphosphatase