Aroma of Cooked Rice (Oryza sativa): Comparison Between Commercial Basmati and Italian Line B5-3

Selected lines of aromatic rice from American cv. A301 were cultivated in Italy, and the agronomic traits and chemical properties related to their aroma were studied. The most characteristic compound responsible for aromatic rice, 2-acetyl-1-pyrroline, was quantified in all lines. Line B5-3, characterized by high 2-acetyl-1-pyrroline content, was investigated in greater detail for its volatile components and was compared with a commercial Basmati rice. Volatiles were collected by steam-distillation. Several classes of compounds were identified and quantified in both samples, including hydrocarbons, aldehydes, alcohols, ketones, heterocyclic, terpenes, disulfides, and phenols. Hexanal was the most abundant compound in both samples, followed by pentanal, 2-acetyl-1-pyrroline, hexanol, benzaldehyde, oct-1-en-3-ol, 4-vinylguaiacol, indole, and trans-2- nonenal. 2-Acetyl-1-pyrroline was present at 570 and 2,350 ppb in Basmati and B5-3, respectively.     

A study of the population structure of the Pacific sardine Sardinops sagax (Jenyns, 1842) in Mexico based on morphometric and genetic analyses

Several studies on the Pacific sardine Sardinops sagax have focused on the identification of stock composition and boundaries, using morphometric and genetic analysis. In this study, geometric morphometric body landmarks and control region mtDNA sequences were used to examine the population structure of sardines along the Pacific coast of the Baja California Peninsula. Samples from commercial landings in Ensenada (ENS), Baja California, and Bahia Magdalena (BM), Baja California Sur, were obtained during 2006–2007. The population hypotheses tested were based on the distribution of sea surface temperature (SST) along the coast, which was previously used to define stocks. A total of 275 sardines from ENS and 119 from BM were used in morphometric analysis. Fifty-three sequences from ENS and 106 from BM were used for genetic comparisons. Morphometric results showed differences among the three groups based on SST, suggesting the existence of different morphotypes. Percentage of molecular variance explained by the differences among three groups was significantly different from zero. However, the distribution of haplotypes in the groups did not show a clear phylogeographic pattern. Additionally, mismatch distributions supported relatively similar historical demographic events in the three groups. Although evidence of phenotypic groups along the Pacific coast of the Peninsula was found, current molecular data did not clearly support the existence of a phylogeographically structured population.     

New records of the distribution and conservation status of the endangered limpet Patella ferruginea in Sardinia (Italy,W Mediterranean)

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