The effect of chitosan-based edible film and high hydrostatic pressure process on the microbiological and chemical quality of rainbow trout ( Oncorhynchus mykiss

The objective of this study is to determine the changes in the chemical and microbiological quality of fresh rainbow trout (Oncorhynchus mykiss Walbaum) fillets during storage at 4 +/- 1 degrees C as a result of chitosan-based edible film coating, vacuum packaging and high pressure application processes. Chemical (pH, total volatile basic nitrogen and thiobarbituric acid index) and microbiological (total mesophilic and total psychrophilic microorganism) shelf life analyses were carried out in 4-day intervals for samples that were vacuum packaged (C), subjected to high pressure after vacuum packaging (high hydrostatic pressure (HHP)), vacuum packaged after being wrapped by chitosan-based film (CFW) and subjected to high pressure after vacuum packaging and being wrapped by chitosan-based film (HHP+CFW ). According to the chemical and microbiological shelf life analysis results of rainbow trout fillets, shelf life increases of 4 days in HHP group samples, 8 days in CFW group samples and 24 days in HHP+CFW group samples were provided in comparison with the control group. In conclusion, it was determined that high pressure and wrapping with chitosan-based film had protective effect both chemically and microbiologically and that the most effective protection was obtained when both methods were used together

Detection and partial molecular characterization of Plum pox virus on almond trees in Turkey

Almond (Prunus dulcis) is one of the well known stone fruit species grown for its unripe fruits and delicious seeds in Turkey. In the Trakya region, however, some prevailing virus infections have reduced almond yields and quality. In ten districts of Trakya, 260 leaf samples were collected from affected almond trees in June 2010. DAS-ELISA assays and RT-PCR tests were employed for the identification of viruses. As a result of these detection studies, five of the 260 leaf samples gathered from symptomatic almond trees had Plum pox virus (PPV), 81 of them had Prunus necrotic ringspot virus (PNRSV), and 11 samples contained Prune dwarf virus (PDV). Only four out of 260 samples had a mixture of these viruses. Partial nucleotide sequences of five almond isolates of PPV were determined and compared with 17 other PPV isolates in databases. Computer analysis of obtained and published nucleotide sequences showed identity ranged from 75.72% to 96.87%. Of the five PPV almond isolates obtained, however, there was a close nucleotide identity of 95.82-96.61% to Turkish isolates. Phylogenetic analysis of nucleotides and amino acids showed that five PPV isolates of almond from the Trakya Region of Turkey were clustered in the same subgroup with PPV-T Turkish isolates in GenBank. Therefore we can consider almond isolates of PPV as PPV-T strain, like the two other isolates from apricot trees in Turkey