Assessing the Potential of Algae Extracts for Extending the Shelf Life of Rainbow Trout (Oncorhynchus mykiss) Fillets.

This study evaluates the potential of different algae extracts (Crassiphycus corneus, Cc; Ulva ohnoi, Uo; Arthrospira platensis, Ap; Haematococcus pluvialis, Hp) as additives for the preservation of rainbow trout fillets. The extracts were prepared with different water to ethanol ratios from the four algae species. The highest ferric reducing antioxidant power (FRAP) was observed in Uo extracted in 80% ethanol. Ap aqueous extract also had considerable FRAP activity, in agreement with a high total phenolic content. Radical scavenging activity (DPPH) was higher in Cc 80% ethanol extract, in agreement with a high total carotenoid content. In fact, when the algae aqueous extracts were assayed on the fish fillets, their antioxidant activity exceeded that of ascorbic acid (ASC). All algae extracts delayed microbial growth and lipid oxidation processes in trout fillets throughout the cold storage period compared to controls, and also improved textural parameters, these effects being more evident for Ap and Hp. With respect to the color parameters, the Hp extract prevented the a* values (redness) from decreasing throughout cold storage, a key point when it comes to colored species, not least salmonids. On the other hand, the Ap extract was not as effective as the rest of treatments in avoiding a* and b* decrease throughout the storage period, and thereby the color parameters were impaired. The results obtained, together with the natural origin and the viability for large-scale cultivation, make algae extracts interesting fish preservative agents for the food industry.

Effects of vacuum and modified atmosphere on textural parameters and structural proteins of cultured meagre (Argyrosomus regius) fillets.

The influence of two preservation strategies (vacuum package and modified atmosphere package) on the post-mortem changes of textural parameters, pH, water holding capacity, sarcoplasmic and myofibrillar proteins, and collagen content of meagre (Argyrosomus regius) fillets was studied. Fillets were stored in a cold room in aerobic (control, C), vacuum (V) and modified atmosphere (MA) package. Samples were withdrawn at six sampling points throughout 15-day storage, and post-mortem changes were assessed. The textural parameters were significantly enhanced in V and MA compared to C. Both V and MA treatments reduced the intensity of a group of myofibrillar protein fractions (140-195 kDa) and increased insoluble collagen compared to C. Consequently, the post-mortem flesh softening in C was attributed to increased proteolysis in both intracellular and extracellular structural proteins. The preservation of the textural and biochemical characteristics of meagre fillets subjected to V and MA treatments makes these two treatments highly recommendable for the commercialization of meagre fillets.

Influence of pre-slaughtering feed restriction on muscle characteristics of farmed sea bass (Dicentrarchus labrax L.) during cold storage.

BACKGROUND: This paper deals with the consequences of dietary restriction or complete starvation before slaughtering on the biochemical and textural characteristics of sea bass muscle. RESULTS: Results showed that only severe feed restriction influenced negatively total body and individual organ weights, and these animals showed lower condition factor as well. Neither moderate feed restriction (up to 50% of the standard ration) kept for 30 days nor total starvation up to 12 days caused significant effects on fish weight and fillet yield. Muscle lipid content was lower in feed-restricted fish, although this parameter was not altered by starvation time. Differences between the two feeding strategies studied were observed in muscle textural and biochemical parameters, and the results point to an influence of the nutritional status on the post-mortem evolution of collagen and myofibrillar proteins, although firmness was not modified. CONCLUSIONS: Moderate feed restriction prior to slaughtering could be advisable in sea bass culture, given that no detrimental effects on fish quality or fish performance were noticed, whereas substantial amounts of feed can be saved.

An improved end-point fluorimetric procedure for the determination of low amounts of trypsin activity in biological samples using rhodamine-110-based substrates.

A novel end-point fluorimetric procedure based on the use of rhodamine-110-labeled specific substrate was developed to determine trypsin activities in biological samples. We evaluated the ability of trichloroacetic acid and acetic acid to stop the enzymatic reaction without hindering the detection of the fluorescence of rhodamine-110 released into the reaction mixture from the specific substrate (CBZ-L-alanyl-L-arginine)(2)-rhodamine-110. Trichloroacetic acid decreased markedly the fluorescence of rhodamine-110, even at low concentrations. On the other hand, the addition of 50 mmol/l acetic acid inactivated efficiently trypsin activity, causing minor effects on rhodamine-110 fluorescence. The proposed procedure was more sensitive than the spectrophotometric end-point method using N-alpha-benzoyl-DL-arginine-p-nitroanilide as substrate. The possibility of carrying out end-point fluorimetric assays improves the performance of monocell fluorimeters by setting specific conditions optimal for each enzyme activity independently of the fluorimeter. This method also allows replicate assays to be conducted simultaneously, resulting in considerable time saving and in increased performance of low-cost equipment.

Cribaje clínico del adolescente obeso sospechoso de Shas / No disponible

INTRODUCCIÓN. Obesidad y las alteraciones del sueño son situaciones cada vez más frecuentes. Los objetivos de este estudio de casos y controles son comprobar si los niños obesos de nuestro medio tienen un mayor riesgo de presentar trastornos respiratorios durante el sueño, si existe correlación de la sospecha clínica con datos polisomnográficos y encontrar claves clínicas sencillas que permitan realizar un cribado de sospecha de estos problemas en asistencia primaria. MATERIAL Y MÉTODOS. Se estudiaron 51 niños seleccionados de manera consecutiva según orden de asistencia a consulta y que presentaban un índice de masa corporal (IMC) superior al percentil 85 y se compararon con 39 niños no obesos con IMC percentil menor 85 reclutados de manera consecutiva, de semejante edad y distribución por sexos que acudían a controles de salud. Se valoró el tamaño amigdalar e istmo velofaringeo radiológicamente. En los que cumplían los criterios clínicos de alteración respiratoria durante el sueño se realizó polisomnografía ambulatoria. RESULTADOS. Los datos clínicos seleccionados muestran una alta especificidad (85.71;CI 95%: 59.78- 111.64) y un alto valor predictivo positivo (96.30;CI 95%: 89.18-103.42) con la presencia de trastornos respiratorios durante el sueño demostrados en la polisomnografía. La presencia de hipertrofia amigdalar junto con estrechamiento del velo faringeo tienen una alta especificad ante la presencia de trastornos respiratorios durante el sueño. CONCLUSIÓN. El tamaño amigdalar mayor o igual a 3 junto con la obstrucción de la vía aérea superior tiene un alto valor de sospecha clínica de padecer un SDB en preadolescentes obesos y puede ser utilizado como un cribado clínico sencillo y rápido (AU)

INTRODUCTION. Obesity and sleep problems are situations increasingly frequent. The aims are to verify if the children with overweight/obesity have a major risk of presenting sleep respiratory disorders, if there exists correlation of the clinical suspicion with polisomnographic information and to find key simple clinics that allow to fulfill the screening of suspicion of these problems in primary care. MATERIALAND METHODS. There were studied 51 children selected of a consecutive way according to order of assistance to consultation and that had an index of corporal mass bigger that 85 percentile and there compared with 39 children with index of corporal mass minor percentile 85 recruited ones of a consecutive way, of similar age and distribution for sexes that were coming to controls of health. The tonsil size was clinical valued and the pharyngeal isthmus by RX. In those who were fulfilling the clinical criteria of sleep respiratory disorders was realized an ambulatory polysomnography. RESULTS. The clinical selected information shows a high specificity (85.71;CI 95%: 59.78- 111.64) and a positive predictive value of 96.30 (CI 95%: 89.18-103.42) with the presence of sleep respiratory disorders in the polysomnography. The presence of hypertrophic tonsils (>3) together with tightening of the pharyngeal istmus they have a discharge specify (80.00;CI 95%: 44.94-115.06) and a positive predictive value of 95.65 (CI 95%: 87.31-103.99) for the presence of sleep respiratory disorders. CONCLUSIONS. The size tonsils bigger or equal to 3 together with the obstruction of the top airway has a high value of clinical suspicion to endure a sleep disorders breathing in preadolescents with overweight and can be used like sifted clinical simply and rapidly (AU)