Inhibition of fatty acids profile changes of cobia (Rachycentron canadum) fillets during frozen storage by packaging under vacuum system

This study was aimed to investigate the effect of vacuum packing (VP) on the fatty acids profiles in cobia (Rachycentron canadum) fillets during an extended frozen storage period. Cobia fillets were treated under vacuum system then stored at -18°C for up to 6 months and compared to control conditions. As a result of a frozen storage period of 6 months, a marked content decrease was found in the fatty acid groups such as MUFA, PUFA and ω-3 PUFA, as well as in the ω-3/ ω-6 ratio. However, a preserving effect on such fatty acid parameters could be observed due to the VP treatment. Assessment of the polyene index (PI) indicated an increased lipid oxidation development as a result of the frozen storage time; however, this increase was partially inhibited by the vacuum packaging. Results indicate that vacuum packaging was a proper way to reduce lipid oxidation in Cobia fillets and extend their shelf life by omitting available oxygen. Thus the employment of VP alone or in combination with other protective strategies is recommended

Comparison of antibacterial activities of Ircinia mutans extracts in two different seasons from Kish Island, Persian Gulf, Iran

Sponges, which constitute the phylum Porifera, are the most primitive of the multicellular animals, among all marine organisms screened. Marine sponges produce the largest number of structurally diversified natural products. In this study we investigated in vitro antimicrobial activity of Ircinia mutans collected from the Kish Island in the Persian Gulf against strains of bacteria Escherichia coli (ATCC 15224), Pseudomonas aeruginosa (ATCC 25619), Staphylococcus aureus (ATCC 1764), and Bacillus subtilis spizizenii (ATCC 6633). Diethyl etter, methanol and aqueous extracts of sponge were evaluated by using the Bacterial Broth Dilution Method. The results showed that the aqueous extracts didn’t have any antibacterial activity. Minimum Inhibitory Concentrations (MIC) of the winter diethyl etter extract was 2 mg/ml for E.coli and 20 mg/ml for P. aeruginosa, whereas the summer diethyl etter extract and both of methanol extracts did not show any activity. The MIC and MBC (Minimum Bacterial Concentration) of summer diethyl etter extracts were 2 mg/ml and 3mg/ml against S. aureus; and 5mg/ml and 10mg/ml when tested on B. subtilis. The MIC and MBC of winter diethyl etter extracts were measured as 1.5 mg/ml and 2mg/ml against S. aurous; and 5mg/ml and 10mg/ml when examined on B. subtilis. Summer and winter methanol and aqueous extracts of I. mutans did not show any activity against these bacteria. Therefore secondary metabolite solutions in diethyl etter contain components with antibacterial properties and can be used as antibiotics products

Quality assessment of fish burgers from deep flounder (Pseudorhombus elevatus) and brushtooth lizardfish (Saurida undosquamis) during storage at -18ºC

Microbiological, chemical and sensory changes of fish burgers prepared from deep flounder (Pseudorhombus elevatus) and brushtooth lizardfish (Saurida undosquamis) were determined during storage at -18ºC for 5 months. Microbiological counts were including total plate count (TPC), total coliform (TC), Staphylococcus aureus, Psychotropic and Escherichia coli decreased throughout the frozen storage . Reduction of microbial load in brushtooth lizardfish was higher than that in deep flounder, except for Staphylococcus aureus counts that was almost equal in both groups. There was a significant increase in pH value in both groups (P<0.05) in first and second months of storage only. Moisture content increased in both groups at the end of 5th month, with increase of moisture in deep flounder fish burgers being higher than that in brushtooth lizardfish burgers. TVB-N values in both groups increased significantly (P<0.05 and P<0.008 for deep flounder and brushtooth lizardfish burgers, respectively) at the end of the second month, however, there was a decrease or no significant change afterward. TBA value of deep flounder fish burgers had a significant decrease (P<0.05) as storage time continued, however, it increased significantly in brushtooth lizardfish burgers at the end of second month (P<0.006) following by a decrease at the end of storage period. Peroxide value (PV) in both groups increased significantly (P<0.05 and P<0.002 in deep flounder and brushtooth lizardfish burgers, respectively) during storage time but a significant decrease was observed at the end of third and fourth months (P<0.005 and P<0.001 in deep flounder and brushtooth lizardfish burgers, respectively). Sensory parameters (color, texture, taste and general acceptability) for two groups decreased significantly (P<0.003 for all parameters in 2 groups) during storage with deep flounder fish burgers receiving higher scores than brushtooth lizardfish burgers at the beginning and end of the storage period

Characterization of the Partitioning System of Myxococcus Plasmid pMF1

pMF1 is the only autonomously replicating plasmid that has been recently identified in myxobacteria. This study characterized the partitioning (par) system of this plasmid. The fragment that significantly increased the retaining stability of plasmids in Myxococcus cells in the absence of selective antibiotics contained three open reading frames (ORFs) pMF1.21-pMF1.23 (parCAB). The pMF1.22 ORF (parA) is homologous to members of the parA ATPase family, with the highest similarity (56%) to the Sphingobium japonicum ParA-like protein, while the other two ORFs had no homologs in GenBank. DNase I footprinting and electrophoretic mobility shift assays showed that the pMF1.23 (parB) product is a DNA-binding protein of iteron DNA sequences, while the product of pMF1.21 (parC) has no binding activity but is able to enhance the DNA-binding activity of ParB to iterons. The ParB protein autogenously repressed the expression of the par genes, consistent with the type Ib par pattern, while the ParC protein has less repressive activity. The ParB-binding iteron sequences are distributed not only near the partitioning gene loci but also along pMF1. These results indicate that the pMF1 par system has novel structural and functional characteristics

The fifth developing plan of Iranian Fisheries Research Institute

Accurate scientific and practical plan for achieving the goals of the Islamic Republic of Iran within the framework of Vision development 1404, is the infrastructure achieving sustainable development of the country. Order to achieve the above mentioned objectives and in order to the comprehensive development plans in the country, Iranian fisheries research organization adjust the fifth developing plan for support of executive related departments in country with mobilization a large number researchers consists of several working groups of ifro affiliated research centers. The fifth developing plan consist of three chapters for report of the forth developing plan and intrudction of research, construction plans and financial support (budjet) for period of 2011-2014 A.C

Edge image description using fractal interpolation

Edge images derived from compressed image databases are described using fractal techniques. The proposed method is able to give affine transformation-invariant description suitable for use in a query-by-example database application. Comparison among the proposed method, polynomial interpolation and spline interpolation is given. It is concluded that fractal interpolation can give a compact description of image contours and is able to cope with random perturbation of the coordinates of the contour points by as much as 25 percent

Efecto de un tratamiento previo con ácido ascórbico sobre el perfil de ácidos grasos de filetes de cobia (Rachycentron canadum) conservada en congelación.

[EN] The present research focuses on the nutritional value of the lipid retention associated with frozen cobia (Rachycentron canadum). The effect of a previous soaking in an aqueous ascorbic acid (AA) solution on the fatty acid profile of fish fillets during a further frozen storage period (–18 °C) was investigated. Two different AA concentrations were tested (0.25% and 0.50%) and compared to control conditions. As a result of the frozen storage period (up to 6 months), marked decreases were found in the contents of fatty acid groups such as monounsaturated, polyunsaturated and n-3 polyunsaturated, as well as in the n-3/n-6 ratio. However, a preserving effect on such fatty acid parameters could be observed resulting from the previous AA treatment, which was greater when applying the 0.50% AA concentration. Assessment of the polyene index indicated an increased lipid oxidation development during the frozen storage time; this increase was partially inhibited by the previous AA soaking.[ES] Este estudio se centra en el valor nutricional lipídico de cobia (Rachycentron canadum) congelada. Para ello, se investiga el efecto que un tratamiento previo con ácido ascórbico (AA) puede tener sobre el perfil de ácidos grasos de filete de pescado durante su conservación en congelación (–18 °C; seis meses). Se aplicaron dos concentraciones de AA (0.25% y 0.50%) que fueron comparadas con muestras control. Como resultado de la conservación en congelación, se observó un descenso importante en grupos de ácidos grasos monoinsaturados, poliinsaturados y poliinsaturados de las serie n-3, así como en la relación n-3/n-6. Sin embargo, el tratamiento previo con AA produjo un efecto protector en estos parámetros, siendo mayor al aplicar AA en la concentración superior. La medida del índice de polienos reflejó un incremento de la oxidación lipídica durante la conservación en congelación; este incremento fue parcialmente inhibido como resultado del tratamiento previo con AA.Peer reviewe

Induction of basal resistance by methyl jasmonate against fusarium culmorum in bread wheat

Fusarium culmorum is a soilborne fungal pathogen, agent of crown and root rot disease (FCRR), responsible of major economic losses in wheat plants. This host-pathogen interaction, following methyl jasmonate (MeJA) application at the beginning of the necrotrophic stage of infection, has not been previously studied at molecular level. In this study, using real-Time quantitative PCR, the emerging role of MeJA in the basal resistance of two bread wheat cultivars against F. culmorum has been investigated. MeJA treatment was dispensed 6 hours after pathogen inoculation (6 hai) to detect the defense response at the beginning of the necrotrophic stage. The expression of phenylalanine ammonia-lyase (PAL), lipoxygenase (LOX), cytochrome P450 (CYP709C1) genes and of some pathogenesis related (PR) genes, including PR3, PR4 and PR9, was examined in both root and crown tissues of the susceptible wheat cultivar Falat and the tolerant cultivar Sumai3. The pathogen responsive defense genes were induced in both cultivars, with a higher level of induction in Sumai3 than in Falat. MeJA treatment reduced the symptoms in cv Falat, whereas no significant effects have been detected in cv Sumai3. In fact, MeJA treatment caused a striking difference in defense gene induction. The genetic change was present in root and crown tissues of both wheat cultivars, demonstrating a systemic signaling pathway. The chemically induced protection correlated with induction of the F. culmorum-responsive genes supports a possible role of jasmonate signaling in regulating basal resistance in wheat-F. culmorum interaction

Methyl Jasmonate Strengthens Wheat Plants Against Root and Crown Rot Pathogen Fusarium culmorum Infection

Root and crown rot of wheat, caused by Fusarium culmorum (Fc), is a serious disease worldwide, particularly in Iran. Currently, the mechanisms underlying resistance to Fusarium-caused diseases are still unknown. Methyl jasmonate (MeJA) has been identified as a vital cellular regulator, and the effect of exogenous MeJA application during wheat-Fc interaction has not been studied previously at the molecular level. This study, using real-time quantitative PCR, was carried out to determine the expression of seven host defense-associated genes consisting of PR3, PR4, PR5, TaPERO, LOX, PAL and cytochrome P450 gene (CYP709C1) at 48, 72 and 96 h after Fc-inoculation (hai) and to investigate the relationship between the induced resistance by MeJA application and the gene expression patterns. The results showed that several genes were induced earlier (48 hai) and to higher levels in the resistant cv. Sumai3 than in susceptible cv. Falat. Many Fc-induced genes were also activated and induced by MeJA particularly during the later stages of infection; however, in contrast to defense-gene induction by the pathogen, there was not a general trend of higher induction in Sumai3 compared to Falat following this chemical treatment. The chemically induced protection significantly reduced the development of necrotic symptoms in both cultivars over a 3-week period after inoculation; however, this reduction was greater in Falat than in Sumai3 relative to the controls. Surprisingly, the expression of these genes was also expressed in crown tissue that had not yet been in contact with the fungus, signifying that a form of systemic response was taking place in this interaction. This is the first work reporting the effect of timing application of MeJA during Fc infection and comparing the defense-related gene expression between root and crown tissues of wheat genotypes. Moreover, soil-drench application of MeJA resulted in strong induction, verifying the success of this application method in systemically activating JA signaling for the first time. These results provided important intimations for designing strategies to curtail diseases caused by Fusarium