Stress resistance induced by paramylon treatment in Artemia
sp.
R. Vismara, S. Vestri, A.M. Frassanito, L. Barsanti,
P. Gualtieri-2004
Journal
of Applied Phycology, 16
(1): 61-67
Abstract:
A
study was undertaken to investigate the effectiveness of paramylon extracted
from the non-photosynthetic WZSL mutant of Euglena gracilis in
potentiating the resistance of the brine shrimp Artemia sp. to
stress conditions resulting from poor growth medium quality and daily
handling. The experimental design incorporated four different treatments: I)
paramylon addition/no growth medium replacement; II) no paramylon
addition/no growth medium replacement; III) paramylon addition/growth medium
replacement; IV) no paramylon addition/growth medium replacement. As shown
by the survival curves of Artemia sp., the addition of paramylon
significantly reduced susceptibility of animals to the stressors. Paramylon
effectively increased also the ability of offspring to withstand poor water
quality and handling damages. Without paramylon almost all offspring died
before adulthood, whereas addition of paramylon allowed the animals to moult
to the adult stage. Moreover, reproductive success (higher number of living
offspring) was enhanced considerably in animals treated with paramylon
treated under both stress conditions. These results show that paramylon
extracted from Euglena represents a promising biologically active
compound for aquaculture purposes. It could be used as a purified product or
as component of whole cells, since the Euglena mutant, because of
the high intracellular amount of paramylon it can accumulate, could be added
to the feed or to water in tanks and ponds without prior processing.
(CNR
Area della Ricerca Pisa, Istituto di Biofisica, Via Moruzzi 1, Pisa, 56124,
Italy, e-mail of P. Gualtieri: paolo.gualtieri@ib.pi.cnr.it)