Marine Algal Bioactivities 137
and proceeded with the identification of the bioactive compounds by GC/MS. In this work, IC 50 values
between 1.5 and 4.3 μg/mL were observed using subfractions of the hexane and dichloromethane extracts.
Although the bioactive compounds have yet to be identified, the volatile compounds found in B. tenella
seem to be fatty acids, low molecular mass hydrocarbons, esters and steroids, and also some less common
compounds as neophytadiene.
Cruz et al. (2009) have also reported leishmanicidal activity for kahalalide F, a cyclic depsipeptide
that can be found in the green alga Bryopsis sp. (Smit 2004), and its synthetic analogues. This peptide
seems to alter and depolarize the plasma membrane of the parasite with consequently fatal biochemical
imbalances. The authors refer to this lethal mechanism as considerably less prone to the development of
resistance than classical drugs.
Antitrypanosomal activity
Nara et al. (2005), Orhan et al. (2006), Allmendinger et al. (2010), Felício et al. (2010), Spavieri et
al. (2010a,b), Süzgeç-Selçuk et al. (2010), and Vonthron-Sénécheau et al. (2011) screened different
marine macroalgae extracts for antitrypanosomal activity against Trypanosoma brucei rhodesiense and
T. cruzi, encompassing 147 species from 56 families of Chlorophyta (15 species/5 families), Ochrophyta
(47 species/16 families) and Rhodophyta (85 species/35 families) phyla from Japan, Turkey, France,
United Kingdom, and Ireland. The species displaying antitrypanosomal activity below 25 µg/mL are
summarized in Table 4.
The data shown in Table 4 was obtained towards T. cruzi trypomastigote using resazurin staining
and intracellular T. brucei rhodesiense amastigote forms by means of the MTT or the β-galactosidase
(chlorophenolred-ß-D-galactopyranoside) assays.
Concerning the activities against T. brucei rhodesiense, the majority of the species with IC 50 values
under 25 µg/mL belong to the Ochrophyta and Rhodophyta phyla. From this group of macroalgae,
the chloroform:methanol extracts of the ochrophytes such as Halidrys siliquosa, Bifurcaria bifurcata,
Cystoseira tamariscifolia, Cystoseira baccata, Sargassum natans, Sargassum muticum, Fucus spiralis,
Fucus vesiculosus, Fucus ceranoides, Pelvetia canaliculata, Chorda filum, and Saccorhiza polyschides
displayed IC 50 < 11 µg/mL (Orhan et al. 2006; Spavieri et al. 2010a).
Although the Ochrophyta phylum displayed the most prominent antiparasitic activities, algae of the
Rhodophyta phylum were also highly active against T. brucei rhodesiense, being the methanolic extract
of Dasya pedicellata, the most potent of the species screened (IC 50 = 0.37 μg/mL; Süzgeç-Selcuk et al.
2010). The chloroform:methanol extracts of other algae from different families as, for example, Corallina
officinalis, Ceramium virgatum, Gelidium pulchellum, Halopitys incurvus, Osmundea pinnatifida, and
Porphyra linearis, exhibited higher IC 50 values (IC 50 < 10 µg/mL; Allmendinger et al. 2010).
The rhodophyte Dasya pedicellata showed the lowest IC 50 value (62.02 μg/mL) against T. cruzi
trypomastigote forms (Süzgeç-Selcuk et al. 2010).
The search for inhibitors of T. cruzi dihydroorotate dehydrogenase (DHOD), a key enzyme for
pyrimidine biosynthesis of the parasite, in methanol extracts of Japanese algae showed that the brown
algae Fucus evanescens and Pelvetia babingtonii were able to halve the recombinant DHOD activity at
a concentration of 50 μg/mL, and were also able to inhibit the growth of T. cruzi cells (Nara et al. 2005).
As observed for the antileishmanial activity of macroalgae, so far, only a few works have explored
the antitrypanosomal activity of isolated compounds from algae. As described by Dos Santos et al.
(2010) for L. donovani parasites, Veiga-Santos et al. (2010) showed that the sesquiterpene elatol isolated
from Laurencia dendroidea is active against the T. cruzi trypomastigote (IC 50 = 1.38 μg/mL) and the
intracellular amastigote (IC 50 = 1.01 μg/mL) forms, being also active against the epimastigote form
(IC 50 = 45.4 μg/mL).
Antiplasmodial activity
Antiplasmodial activity has been screened on different algae from France, Turkey, India, Brazil and
Philippines, namely Chlorophyta (11 species/5 families), Ochrophyta (12 species/6 families), and
and proceeded with the identification of the bioactive compounds by GC/MS. In this work, IC 50 values
between 1.5 and 4.3 μg/mL were observed using subfractions of the hexane and dichloromethane extracts.
Although the bioactive compounds have yet to be identified, the volatile compounds found in B. tenella
seem to be fatty acids, low molecular mass hydrocarbons, esters and steroids, and also some less common
compounds as neophytadiene.
Cruz et al. (2009) have also reported leishmanicidal activity for kahalalide F, a cyclic depsipeptide
that can be found in the green alga Bryopsis sp. (Smit 2004), and its synthetic analogues. This peptide
seems to alter and depolarize the plasma membrane of the parasite with consequently fatal biochemical
imbalances. The authors refer to this lethal mechanism as considerably less prone to the development of
resistance than classical drugs.
Antitrypanosomal activity
Nara et al. (2005), Orhan et al. (2006), Allmendinger et al. (2010), Felício et al. (2010), Spavieri et
al. (2010a,b), Süzgeç-Selçuk et al. (2010), and Vonthron-Sénécheau et al. (2011) screened different
marine macroalgae extracts for antitrypanosomal activity against Trypanosoma brucei rhodesiense and
T. cruzi, encompassing 147 species from 56 families of Chlorophyta (15 species/5 families), Ochrophyta
(47 species/16 families) and Rhodophyta (85 species/35 families) phyla from Japan, Turkey, France,
United Kingdom, and Ireland. The species displaying antitrypanosomal activity below 25 µg/mL are
summarized in Table 4.
The data shown in Table 4 was obtained towards T. cruzi trypomastigote using resazurin staining
and intracellular T. brucei rhodesiense amastigote forms by means of the MTT or the β-galactosidase
(chlorophenolred-ß-D-galactopyranoside) assays.
Concerning the activities against T. brucei rhodesiense, the majority of the species with IC 50 values
under 25 µg/mL belong to the Ochrophyta and Rhodophyta phyla. From this group of macroalgae,
the chloroform:methanol extracts of the ochrophytes such as Halidrys siliquosa, Bifurcaria bifurcata,
Cystoseira tamariscifolia, Cystoseira baccata, Sargassum natans, Sargassum muticum, Fucus spiralis,
Fucus vesiculosus, Fucus ceranoides, Pelvetia canaliculata, Chorda filum, and Saccorhiza polyschides
displayed IC 50 < 11 µg/mL (Orhan et al. 2006; Spavieri et al. 2010a).
Although the Ochrophyta phylum displayed the most prominent antiparasitic activities, algae of the
Rhodophyta phylum were also highly active against T. brucei rhodesiense, being the methanolic extract
of Dasya pedicellata, the most potent of the species screened (IC 50 = 0.37 μg/mL; Süzgeç-Selcuk et al.
2010). The chloroform:methanol extracts of other algae from different families as, for example, Corallina
officinalis, Ceramium virgatum, Gelidium pulchellum, Halopitys incurvus, Osmundea pinnatifida, and
Porphyra linearis, exhibited higher IC 50 values (IC 50 < 10 µg/mL; Allmendinger et al. 2010).
The rhodophyte Dasya pedicellata showed the lowest IC 50 value (62.02 μg/mL) against T. cruzi
trypomastigote forms (Süzgeç-Selcuk et al. 2010).
The search for inhibitors of T. cruzi dihydroorotate dehydrogenase (DHOD), a key enzyme for
pyrimidine biosynthesis of the parasite, in methanol extracts of Japanese algae showed that the brown
algae Fucus evanescens and Pelvetia babingtonii were able to halve the recombinant DHOD activity at
a concentration of 50 μg/mL, and were also able to inhibit the growth of T. cruzi cells (Nara et al. 2005).
As observed for the antileishmanial activity of macroalgae, so far, only a few works have explored
the antitrypanosomal activity of isolated compounds from algae. As described by Dos Santos et al.
(2010) for L. donovani parasites, Veiga-Santos et al. (2010) showed that the sesquiterpene elatol isolated
from Laurencia dendroidea is active against the T. cruzi trypomastigote (IC 50 = 1.38 μg/mL) and the
intracellular amastigote (IC 50 = 1.01 μg/mL) forms, being also active against the epimastigote form
(IC 50 = 45.4 μg/mL).
Antiplasmodial activity
Antiplasmodial activity has been screened on different algae from France, Turkey, India, Brazil and
Philippines, namely Chlorophyta (11 species/5 families), Ochrophyta (12 species/6 families), and