The in vitro, ex vivo, and in vivo experimental findings of Nephrolepis exaltata

Nephrolepis exaltata (L.) Schott decreases the heartbeats of cockroaches and it was postulated that the plant could be an anticholinesterase agent and could have effects. It was performed: (a) In vitro: hydroalcoholic extract of N. exaltata was pharmacognostically characterized, the cholinesterase activity determined with 1.0 and 3.0 mg/ml, comparing to positive control and negative control, and the preliminary toxicity was evaluated with 5 mg/plate through Salmonella/microsome assay using TA100 strain; (b) Ex vivo:  2, 5, or 10 mg of extract was assayed on mouse phrenic nerve-diaphragm preparation using conventional myographic technique; and (c) In vivo: 2.0, 1.0 or 0.5 g of extract was exposed to Allium cepa root cells, using onions bulbs for further measuring and microscopic analysis. The cholinesterase activities (U/L, n=3) of 1.0 and 3.0 mg/mL fern extract were of 2,866.6 ± 200.7 and 3,092.9 ± 214.2, respectively, versus 87.1 ± 58.1 (p<0.05) for positive control. The extract showed the absence of micronucleus and inhibited the root growth reaching 100% at 2 mg.  The plant has no anticholinesterase activity, it is not toxic on bacterial reverse mutation or nerve-muscle parameters and is not genotoxic on A. cepa assay, but inhibits the root growth of A. cepa.   Key words: Allium cepa, cholinesterase, fern, pharmacognosy, Salmonella.