Caratteristiche merceologiche, nutrizionali, sensoriali e di freschezza di Nasello (Merluccius merluccius), Lanzardo (Scomber japonicus) e Suro (Trachurus trachurus)

Three finfish species frequently caught in the waters of the Gulf of Manfredonia (Apulia, Italy) were studied in order to know how the flesh composition (proximate, fatty acid, macro- and micro- element contents) could be affected by the season effect. The species we examined were European hake (Merluccius merluccius), chub mackerel (Scomber japonicus) and horse mackerel (Trachurus trachurus), which were analysed at the raw state in three catch season and after cooking in two catch season. More precisely, European hake and chub mackerel caught during winter, summer and fall were analysed at the raw state. The composition of the flesh of grilled European hake and chub mackerel was study on fish caught in winter and fall. Horse mackerel of summer and winter catches were analysed both at the raw and grilled state. Furthermore, an overall sensory profile was outlined for each species in two catch season and the relevant spider web diagrams compared. On the whole, two hundred and eighty fish were analysed during this research project in order to obtain a nutritional profile of the three species. One hundred and fifty was the overall number of specimens used to create complete sensory profiles and compare them among the species. The three finfish species proved to be quite interesting for their proximate, fatty acids, macro- and micro-element contents. Nutritional and sensory changes occurred as seasons elapsed for chub and horse mackerel only. A high variability of flesh composition seemed to characterise these two species. European hake confirmed its mild sensory profile and good nutritional characteristics, which were not affected by any season effect.

Approcci molecolari e bioinformatici volti alla caratterizzazione di Vgt1, QTL coinvolto nella regolazione dell'epoca di fioritura in Zea Mays

The genetic control of flowering time has been addressed by many quantitative trait locus (QTL) studies. A survey of the results from 29 independent studies reporting information on 441 QTLs led to the production of a QTL consensus map, which enabled the identification of 59 chromosome regions distributed on all chromosomes and shown to be frequently involved in the genetic control of flowering time and related traits. One of the major QTLs for flowering time, the Vegetative to generative transition 1 (Vgt1) locus , corresponds to an upstream (70 kb) non-coding regulatory element of ZmRap2.7, a repressor of flowering. A transposon (MITE) insertion was identified as a major allelic difference within Vgt1. One of the hypotheses is that Vgt1 might function by modifying ZmRap2.7 chromatin through an epigenetic mechanism. Therefore, the methylation state at Vgt1 was investigated using an approach that combines digestion with McrBc, an endonuclease that acts upon methylated DNA, and quantitative PCR. The analyses were performed on genomic DNA from leaves of six different maize lines at four stages of development. The results showed a trend of reduction of methylation from the first to the last stage with the exception of a short genomic region flanking the MITE insertion, which showed a constant and very dense methylation throughout leaf development and for both alleles. Preliminary results from bisulfite sequencing of a small portion of Vgt1 revealed differential methylation of a single cytosine residue between the two alleles. ZmRap2.7 expression was assayed in the four developmental stages afore mentioned for the six genotypes, in order to establish a link between methylation at Vgt1 and ZmRap2.7 transcription. To assess the role of Vgt1 as a transcriptional enhancer, two reporter vectors for stable transformation of plants have been developed.