Volatile composition of light red wines aged in Canary pine barrels from La Palma (Canary Islands, Spain)
Multivarietal wines aged in barrels made from the resinous heartwood of the Canary Pine (Vinos de Tea) in La Palma (Canary Islands, Spain) were analysed, together with a control sample and a Greek Retsina wine. The concentrations of various families of varietal and fermentative volatile compounds were determined by gas chromatography and mass spectrometry. Results showed the significant presence of the terpene family, especially terpinen-4-ol and α-terpineol (probably derived from contact with the resinous wood of the barrels), regardless of grape variety. Samples taken from commercial wineries presented significantly lower concentrations of α-terpineol than samples from traditional artisan producers. The principal component analysis clearly differentiated both from the Retsina. It also revealed a correlation between the length of time that wine aged in Canary pine barrels and a sharp increase in α-terpineol, which can be considered a marker of the typicity of these unique traditional wines on the verge of disappearance.
Alciporin, a pore-forming protein as complementary defense mechanism in Millepora alcicornis
Millepora alcicornis (Cnidaria: Hydrozoa), known as fire coral, is a tropical species settled in marine ecosystems of the Canary Islands in the last years. This hydrocoral biosynthesizes toxins involved in chemical defense and prey capture mechanisms. Toxicological studies have shown that the venom contained in the nematocysts of Millepora species is mainly composed of thermolabile proteins that display hemolytic activity, causing skin irritation and burn-like lesions upon contact. As a continuation of a previous study, the chromatographic fractionation of the aqueous extracts of M. alcicornis has confirmed the coexistence of proteins of different nature responsible for the hemolytic effects of red blood cells (RBCs) through two different mechanisms. Aside from the already described phospholipase A2 (PLA2) activity, in this work the presence of alciporin, a pore-forming protein (PFP), has been established for the first time for M. alcicornis. The sequence analysis revealed that alciporin fit an actinoporin with high homology to stichotoxins. The hemolytic effects of alciporin were analyzed and sphingomyelin was identified as its biological target. Also, the evolution of the hemolytic damage produced at the nanoscale has been studied using atomic force microscopy (AFM).
Nocchi, Nathalia; González-Orive, Alejandro; Hernández-Creus, Alberto; Lorenzo-Morales, Jacob; Rodríguez, Adriana; Morchón, Rodrigo; Díaz-Marrero, Ana R.; Fernández, José J.
Genetic Characterization of a Plum Landrace Collection from La Palma, Canary Islands
A plum collection located in the island of La Palma, Canary Islands, composed of twenty-nine European and Japanese plums was analyzed using nine simple sequence repeat (SSR) highly polymorphic loci. First, a cytometry flow analysis was performed to determine the ploidy level. Sixteen accessions turned out diploid and thirteen hexaploid. According to morphological characteristics, fourteen of the sixteen diploid accessions were assigned to Prunus salicina, and two accessions to P. cerasifera. All the hexaploid accessions were assigned to P. domestica. The 29 accessions were compared using SSR markers with twenty-two P. domestica accessions maintained at the CITA plum germplasm collection located in Zaragoza, Aragón, Spain. A principal component analysis (PCA) and a clustering approach grouped the accessions according to the assigned species and geographical location, while some synonyms and homonyms were found within La Palma accessions. The two principal components explained 80.3% (67.3% and 13%, respectively) of the total variance. A tree generated with UPGMA hierarchical clustering and Bruvo distance grouped the accessions in two main clusters according to ploidy level and species assignment. The STRUCTURE approach clearly differentiated La Palma diploid accessions and some of the hexaploid accessions from those of the CITA collection. The results obtained could be used for management and conservation purposes of this valuable local plum germplasm.
Pérez Méndez, Verónica; Rodrigo, Javier; Abdallah, Donia; Larranaga, Nerea; Hormaza, José I.