29 research outputs found
Recovery of Natural Antioxidants from Fruit Juice Industry Residuals by Ultrasound-Assisted Extraction and Response Surface Methodology
Fruit processing industries produce by-products that are good sources of natural antioxidants. These residuals are non-toxic and available in large quantities. A central composite design (CCD) and response surface methodology (RSM) were used to optimize experimental conditions. The processing variables were solvent type, solvent to solid ratio, ethanol concentration, temperature, and time. The responses were total phenolic content (TPC), scavenging activity of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, and yield. The optimal conditions were 70% ethanol— water mixture as a food grade solvent, temperature of 35 °C and extraction time 60 min for obtaining extracts with maximum of total phenolic content. Predicted values for total phenolic content in pear, apricot, and peach were 24.7, 19.3, and 10.4 mg gallic acid equivalents per 100 g fruit residual, respectively
Comparison of neutral anolyte solution and malachite green efficiency on fungal contamination control of rainbow trout (Oncorhynchus mykiss) eggs in incubation stage
One of the important problems in Rainbow trout production industry is egg fungal infection especially saprolegniasis which is the most important mortality factor in Rainbow trout hatcheries. Controlling saprolegniasis in hatcheries was done using green malachite in the past years, which is a very effective fungicide. Nowadays, due to the prohibition of using green malachite, effort is done to replace it with other materials as an effective fungicide. Some of the most important materials which have been examined are formalin, sodium chloride and hydrogen peroxide etc. The aim of this study was to evaluate the effects of neutral anolyte on the mortality percent of rainbow trout eggs and produced larvae in point of view of growth indices and survival until yolk sac absorption and larvae active feeding in incubation phase comparing with green malachite to be able to introduce a suitable alternative. This study was carried out in a complete randomly plan with 7 treatments and 3 replications (21 troughs in general), in 20*35*70 cm (length*width*depth) Californian troughs containing an incubator. Treatments included anolyte solutions constant bathing with 0.5 and 0.25 ppm concentrations and periodic anolyte treatments with 2 ppm concentrations (every 2 days), positive control infected with fungus without any disinfectant and negative control without any infection or disinfectant. 300 grams of newly propagated green eggs of rainbow trout which were provided from one of the fish hatcheries in Haraz Road and acclimated with the trough’s water temperature, were distributed in one layer at the bottom of the trough basket. All treatments, except negative control, were infected with saprolegnia, taken from infected eggs of rainbow trout which were previously provided from one of the fish hatcheries of 2000 Road in Tonekabon. The treatments took one month to complete. The studied variables included hatching percent, percent of eyed eggs, abnormality percent and percent of unfertilized eggs, from which percent of eyed eggs was calculated and recorded in the middle and the rest of the variables at the end of the test. In this study Paired-sample T-student test, Levene’s test, one-way ANOVA and Bonferroni’s test was used. For examining egg abnormality, hatching, fungus infection and eyed eggs, first the percent of the variables were specified and then for comparing the rate of abnormality in one of the anolyte treatments (which had the least abnormality) and green malachite, Mann-Whitney test was carried out. This comparison was done to analyze the rate of hatching, fungus infections, eyed eggs, resulting from the materials used in different treatments, using one-way ANOVA Bonferroni’s tests. Results showed that in lower anolyte concentrations (0.5 and 0.25 ppm), the number of fungal colonies of hatchery water and the percent of egg fungus infection were significantly higher than higher concentrations of anolyte (100 ppm and 30 ppm) and green malachite. In other words with concentration increase, the fungicidal effect has also increased. In evaluating the percent of eyed eggs, statistical results showed that eyed eggs percent in 0.25 ppm treatment and green malachite treatment were significantly higher than the other three anolyte treatments. This result can explain egg hatching in 0.25 ppm concentrations and not seeing hatching in the (other) remaining three doses. Between the treatments of 0.25 ppm and green malachite, the group of 0.25 ppm anolyte can be a better disinfectant for rainbow trout eggs compared to green malachite, for fish farmers, due to the high percent of eyed eggs and the low total count of fungus. The results of this study showed that the amount of abnormality in 0.25 ppm treatment has been higher compared to the green malachite group. Because this study was the first research on using anolyte as a fungicide in rainbow trout hatcheries, therefore for more specific study of the concentrations, the timing of usage and the factors affecting these two, more vast and general research is needed
Gene Transfer to Chicks Using Lentiviral Vectors Administered via the Embryonic Chorioallantoic Membrane
The lack of affordable techniques for gene transfer in birds has inhibited the advancement of molecular studies in avian species. Here we demonstrate a new approach for introducing genes into chicken somatic tissues by administration of a lentiviral vector, derived from the feline immunodeficiency virus (FIV), into the chorioallantoic membrane (CAM) of chick embryos on embryonic day 11. The FIV-derived vectors carried yellow fluorescent protein (YFP) or recombinant alpha-melanocyte-stimulating hormone (α-MSH) genes, driven by the cytomegalovirus (CMV) promoter. Transgene expression, detected in chicks 2 days after hatch by quantitative real-time PCR, was mostly observed in the liver and spleen. Lower expression levels were also detected in the brain, kidney, heart and breast muscle. Immunofluorescence and flow cytometry analyses confirmed transgene expression in chick tissues at the protein level, demonstrating a transduction efficiency of ∼0.46% of liver cells. Integration of the viral vector into the chicken genome was demonstrated using genomic repetitive (CR1)-PCR amplification. Viability and stability of the transduced cells was confirmed using terminal deoxynucleotidyl transferase (dUTP) nick end labeling (TUNEL) assay, immunostaining with anti-proliferating cell nuclear antigen (anti-PCNA), and detection of transgene expression 51 days post transduction. Our approach led to only 9% drop in hatching efficiency compared to non-injected embryos, and all of the hatched chicks expressed the transgenes. We suggest that the transduction efficiency of FIV vectors combined with the accessibility of the CAM vasculature as a delivery route comprise a new powerful and practical approach for gene delivery into somatic tissues of chickens. Most relevant is the efficient transduction of the liver, which specializes in the production and secretion of proteins, thereby providing an optimal target for prolonged study of secreted hormones and peptides
Translational readthrough in Tobacco necrosis virus-D
AbstractThe plus-strand RNA genome of Tobacco necrosis virus-D (TNV-D) expresses its polymerase via translational readthrough. The RNA signals involved in this readthrough process were characterized in vitro using a wheat germ extract translation system and in vivo via protoplast infections. The results indicate that (i) TNV-D requires a long-range RNA-RNA interaction between an extended stem-loop (SL) structure proximal to the readthrough site and a sequence in the 3'-untranslated region of its genome; (ii) stability of the extended SL structure is important for its function; (iii) TNV-D readthrough elements are compatible with UAG and UGA, but not UAA; (iv) a readthrough defect can be rescued by a heterologous readthrough element in vitro, but not in vivo; and (v) readthrough elements can also mediate translational frameshifting. These results provide new information on determinants of readthrough in TNV-D and further support the concept of a common general mechanism for readthrough in Tombusviridae
Gas-Screen Slotted Quartz Tube Atomic Absorption Spectrometry: A Remedy for Reducing Interference Effects of Calcium and Chromium
A simple device for the reduction of nonspectral interferences in flame atomic absorption spectrometry is proposed. It has been reported that the use of a gas screen (GS) system together with a slotted quartz tube (SQT) enhances the residence time of analyte atoms in measurement zone even more than the SQT alone. This combination causes enhancement of sensitivity and improves the reproducibility of absorbance measurements. In addition, it protects the optical windows of the atomic absorption spectrometer. The operational mechanism of gas screen is simply applying two argon gas walls at both ends of SQT to provide an environment that is partly protected from air. This action enhances the sensitivity of measurement. In this study, interference effects of excess amounts of calcium and chromium on the measurements of Cd, Co, Cu, Pb, Mn, Ni, Se, and Zn were studied using flame AAS. The presence of both Ca and Cr cause higher absorbance values; it is suggested that this is due to formation of oxide species of Ca and Cr and as a result analyte oxide production is suppressed. Therefore, analyte free atom population and sensitivity are enhanced. This enhancement results in a positive error in measurements. For instance, presence of solely 8.0mgL1 of Cr or Ca for Pb as the analyte enhances the signals by 75% and 56%, respectively. When SQT or GS-SQT is used, this effect is significantly reduced