Biology Reference
In-Depth Information
12.4.4
Asparagopsis
Species
Gametophytes of
Asparagopsis armata
and
A. taxiformis
represent promising
sources of pharmaceutical agents of remarkable anti-protozoan, bactericidal, and
fungicidal activities (McConnell and Fenical
1977
; Woolard et al.
1979
; Paul et al.
2006
; Salvador et al.
2007
; Genovese et al.
2009
). In addition,
Asparagopsis
species
produce valuable natural secondary metabolites such as compounds with consider-
able antimicrobial activity against
vibrio harveyi
strains, useful in cosmetics indus-
try and animal aquaculture (Salvador et al.
2007
; Manilal et al.
2009
); compounds
of cytotoxic activity against cancer cells (Zubia et al.
2009
) and as preservatives in
industrial applications (Kraan and Barrington
2005
). Furthermore, “
Falkenbergia”
stages have been successfully cultivated in southern Portugal and can be used as
continuous, rapidly growing bio-filter systems for the effluent of commercial fish
farms (Schuenhoff et al.
2006
; Figueroa et al.
2008
; Mata et al.
2010
). Introduced in
Ireland in 1939, and following population decline due to inadequate temperature for
sexual reproduction,
Asparagopsis armata
is now commercially cultivated. The
persistence of this species along the Irish West coast seems to be due to continued
replenishment from a single aquaculture operation (Kraan and Barrington
2005
).
Both
A. taxiformis
and
A. armata
exhibit a number of invasive traits, including
vegetative propagation of gametophytes and tetrasporophytes, frequent sexual
reproduction of tetrasporophytes, and a suite of halogenated secondary metabolites
that increase resistance to herbivory (Boudouresque and Verlaque
2002
; Paul et al.
2006
; Williams and Smith
2007
). In addition, polyploidy has been associated with
the extraordinary invasive success of the Indo-Pacific Mediterranean linage 2 of
A. taxiformis
(Andreakis et al.
2009
). Furthermore, “
Falkenbergia
” is particularly
well suited to human-mediated transport (ballast water) and capable of surviving
for long periods as free-floating or loosely attached filaments transported on ships,
animals, and other materials in aquaculture (Flagella et al.
2007
).
12.4.5
Caulerpa
Species
Among three genetically distinct ESUs of the
Caulerpa racemosa
species-complex
occurring in the Mediterranean Sea, the so-called
C. racemosa
var.
cylindracea
(Sonder) Verlaque, Huisman and Boudouresque, is highly invasive.
Caulerpa
species are greatly valued for human consumption due to their high vitamin
and protein content (“sea grapes”,
C. racemosa
var
laetevirens
,
C. racemosa
,
C. geminata
,
C. hodgkinsoniae
) or pleasant taste (“green caviar”,
C. lentillifera
)
and have been identified in several countries as high-value candidates for cultiva-
tion and commercial production (Matanjun et al.
2009
).
Caulerpa
species also offer
promising potential for bioremediation of nutrient-enriched effluent from intensive
tropical aquaculture systems because of their high nutrient uptake rates (linked to
high growth rates) and the fact
that many
Caulerpa
species are native and
