Study of sub-Antarctic limpets metabolism to improve the resource sustainability

GONZÁLEZ PAULA M.; PUNTARULO S.; MALANGA, G.

Enfoques interdisciplinarios para la sustentabilidad del ambiente: libro de trabajos completos del II Congreso Internacional de Ciencia y Tecnología Ambiental, y II Congreso Nacional de la Sociedad Argentina de Ciencia y Tecnología Ambiental.

Sociedad Argentina de Ciencia y Tecnología Ambiental

Lugar: Buenos Aires; Año: 2015; p. 187 - 192

The exploitation of benthonic resources (Concholepas, limptes, sea urchins, razorclams and clams, etc.) is an important fraction within the craft catch. Theactive harvest of these species generates a high use of natural banks, whichmay diminish the population densities and change the specific biodiversity, andturning them in threatened species. In particular, limpets of the genus Nacella, Patella, Fisurella are highlyexploited in Chile, Peru, Spain and other European and Asian countries. InArgentina, their consumption and capture is limited to restaurants or families,and there is not any official fishery regulation being applied. Even though, agood quality of the limpet flesh is acknowledged; neither their baselinenutritional contribution nor their food safety is known. The main objective ofthis work was to obtain basic information on the metabolism, biochemicalcomposition and antioxidant activity in the gills of two sub-Antarctic limpets(Beagle Channel, Tierra del Fuego, Argentina) Nacella magellanica and Nacelladeaurata, collected during summer time. Gills were chosen for the presentstudy since is the first tissue of the limpets in contact with the surroundingwater and may reflect the initial impact of the effects of environmentalchanges. Limpets were measured and weighted (N. deaurata: valve length 52±8 mm, fresh weight 12±5 g; and N. magellanica: 51±6 mm and 16±5 g, respectively)and gills were immediately separated and conserved at -80ºC. No significantdifferences were observed between both species in the content of proteins, carbohydrates,lipids and ashes. Lipid radical content, analyzed as an index of oxidativedamage to lipids, resulted 3.5-fold higher in N. deaurata as compared to N.magellanica. The ascorbyl radical content was 224% higher in N. deaurata than in N. magellanica. Catalase activity was 2.6±0.3 and 5.8±0.7 pmol/mgprot, and superoxide dismutase activity was 1.9±0.3 and 3.1±0.8 U/mg prot, in N. deaurata and N. magellanica, respectively. The activity of these antioxidantenzymes was significantly different between both species. The data presentedhere suggested that N. magellanica, anintertidal species which is exposed to extreme environmental conditions, has ahigher antioxidant capacity than N.deaurata, a subtidal species. This increased antioxidant protection wouldbe responsible of preventing the lipid damage. A reduced deterioration oflipids is associated to an improvement in the organoleptic characteristics and adecrease in the stress during conservation and commercialization. These studieswould contribute to find a strategy that would make possible a sub-exploitationprogress of an important resource, by improving the sustainable managementopportunities of native species of market value.