In vivo evaluation of antiparasitic activity of plant extracts on Nosema ceranae (Microsporidia)

摘要

This study evaluated the activity of plant extracts on Nosema ceranae development and their toxicity on the infected host Apis mellifera. Newly emerged bees were fed ad libitum with enriched syrups after individual infection. Diets consisted of ethanolic extracts obtained from Artemisia absinthium, Allium sativum, Laurus nobilis, and Ilex paraguariensis diluted in syrup at 1% and 10% concentrations. Examination of individual midgut homogenates on day 19 post-infection indicated that 1% concentration of L. nobilis extract significantly inhibited N. ceranae development. Absinth extract, previously reported as effective against Nosema apis, did not diminish the number of N. ceranae spores throughout the experiment. Ten percent concentrations showed high toxicity on infected bees, but also a significant activity diminishing parasitosis development in short periods. Syrups with the addition of extracts were consumed avidly as the control, even more in some cases. The present study constitutes the first report of antiparasitic activity in vivo of plant extracts against the Microsporidian N. ceranae and postulate natural substances as an alternative for antiparasitic treatment.