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Methylated soy and chickpea proteins (MSP and MCP, respectively), and 11S globulin (a soy protein fraction), are characterized by net positive charges and a more hydrophobic nature, nominating them as antiviral proteins. Under greenhouse conditions, potato plants (cv. Spunta) mechanically infected with potato virus Y (PVY) and potato virus X (PVX) were treated with MSP, MCP, and 11S globulin at different concentrations, after ten days of infection. The three tested substances inhibited the viral propagation, where the concentration 500 µg ml−1produced the maximum antiviral action. This influence was further augmented by applying the material twice 10 and 20 days after the viral infection. Assessing the viral load by a double antibody sandwich ELISA (DAS-ELISA), dot-blot hybridization, and reverse transcription-polymerase chain reaction (RT-PCR) confirmed the viral inhibition, in the following order: MSP > MCP > 11S globulin. Bringing the virus in contact with MCP produced deformed TEM (transmission electron microscope) viral micrographs referring to a potential direct action of the substance on the virus. The tested materials' antiviral activity at 500 µg ml−1was positively reflected on the growth and yield of PVY or PVX-infected potato plants cultivated under open field conditions in January. Considerably high increases in the tuber yield of either PVY-infected (68, 42, and 36%) or PVX-infected plants (52, 41 and 30%), were produced by the treatment with MSP, MCP and 11S (500 µg ml−1), respectively.

Delilaand Rosea1anthocyanin accumulation genes were subjected to bioinformatics analysis. Delila protein has 56–69% similarity with different anthocyanin-rich plants, while Rosea1 protein has 83–87% with anthocyanin-rich plant proteins. This study aimed at transferring Delilaand Rosea1genes from the transgenic Micro-tom tomato cultivar to the Moneymaker tomato cultivar using traditional breeding for enhancing their fruit anthocyanin content. Results of all produced F1 plants of manual hybridization between both cultivars were consistent with the Mendelian inheritance hypothesis. Plants of F2 populations showed a 3:1 Mendelian segregation proportion (75% of plants have anthocyanin pigmentation). Seeds of F2 were individually cultured to get four homozygous lines with anthocyanin accumulation in fruits. The total anthocyanin in the anthocyanin-enriched inbred fruit (3 g/kg DM) represented a relative increase of about 131% of the parent level. The total phenolic compounds in inbred tomato fruits were 54.9 mg/100 g DM referring to a relative increase of about 51% of the respective parent plant. The antioxidant activity of inbred fruit at maturity (m) was 83.5% compared with 91% for TBHQ. The inbred (m) tomato fruit extract reduced the growth of G–bacteria G+bacteria by 99% and 95%, respectively.

The current research aimed to estimate the effect of dietary supplementation with glycinin isolated from soybeans on the growth performance, carcass traits, and selected blood metabolites of broiler chicks. A total of 200 1-wk-old broiler chicks were administered diets without glycinin (control treatment) or diets supplemented with 3 concentrations of soy glycinin (0.5, 1.0, or 1.5 g/kg of feed) for 6 wk. At the end of the feeding period, body weight was significantly higher in broiler chicks with glycinin supplementation (P< 0.05 or 0.01). The best values for body weight and body weight gain were recorded in the groups fed diets supplemented with 0.5 and 1.0 g glycinin/kg feed. Feed conversion was significantly (P< 0.05) improved in broilers in the glycinin-supplemented groups during the 1 to 6 and 3 to 6 wk growth periods. The highest value of breast yield was observed in broiler chicks supplemented with glycinin at a concentration of 1.0 g/kg of feed. Water-holding capacity increased with increasing concentrations of glycinin in the feed, up to 1.0%. Serum creatinine and urea concentrations decreased gradually (P< 0.01) as the concentration of glycinin in the feed increased. Broiler chicks receiving increasing concentrations of glycinin exhibited significantly (P< 0.01) lower levels of serum triglycerides, total cholesterol, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol. All meat samples from broiler chicks supplemented with glycinin had significantly higher catalase activities. These data suggest that feeding broiler chicks diets supplemented with soy glycinin (0.5 to 1.5 g/kg of feed) can improve feed conversion, enhance body weight gain, and lower abdominal fat.

The study sought to investigate the impact of a holistic high-power microwave technology during all stages of the extraction on the quality, time of extraction, and degree of deacetylation (DD) of shrimp chitosan (SC) and crab chitosan (KC). The demineralization and deproteinization stages took 7 and 8 min, at 750 and 875 W, respectively. The deacetylation process was conducted at two powers, 875 W and 1250 W, for 10, 15, and 20 min. It only took 25 min at 875 W to successfully prepare chitosan with a high DD and 30 min to reach the maximum DD. The highest DDs by the potentiometric titration method, FTIR, and 1H NMR of SC were 86.6%, 86.7%, and 83%, compared to 83.8%, 82.7%, and 80% for KC, respectively. Extracted SC had 79% solubility, 14.125 kDa, a 46.57% crystallinity index, 705.40% WBC, and 434.60% FBC, against 74.5%, 16.982 kDa, 74.14%, 689.82%, and 413.20% for KC, respectively. The study proved that 30 min of holistic high-power microwave at 875 W produced low-molecular-weight chitosan with relatively high deacetylation and low content of viscosity, crystallinity, and protein residue. The technique can provide a feasible alternative to the commercial production of low-molecular-weight chitosan in less time and energy.

ABSTRACTMycobacterium marinumis an opportunistic pathogen inducing infection in fresh and marine water fish. This pathogen causes necrotizing granuloma like tuberculosis, morbidity and mortality in fish. The cell wall-associated lipid phthiocerol dimycocerosates, phenolic glycolipids and ESAT-6 secretion system 1 (ESX-1) are the conserved virulence determinant of the organism. Human infections with Mycobacterium marinumhypothetically are classified into four clinical categories (type I–type IV) and have been associated with the exposure of damaged skin to polluted water from fish pools or contacting objects contaminated with infected fish. Fish mycobacteriosis is clinically manifested and characterized in man by purple painless nodules, liable to develop into superficial crusting ulceration with scar formation. Early laboratory diagnosis of M. marinumincluding histopathology, culture and PCR is essential and critical as the clinical response to antibiotics requires months to be attained. The pathogenicity and virulence determinants of M. marinumneed to be thoroughly and comprehensively investigated andunderstood. In spite of accumulating information on this pathogen, the different relevant data should be compared, connected and globally compiled. This article is reviewing the epidemiology, virulence factors, diagnosis and disease management in fish while casting light on the potential associated public health hazards.

Protein isolates from soybean and chickpea, as well as their methylated esters, were tested for their inhibitory action against the propagation of pathogenic bacteria in raw milk during its storage either at room temperature or under refrigeration. Raw milk was inoculated with a mixed culture of Listeria monocytogenesScott A and Salmonella entericaserovar Enteritidis strain PT4 at ca. 2 log CFU ml–1. Aerobic plate count, coliform count, and presumptive E. coliin raw milk treated with esterified legume proteins were inhibited by 2 to 3 log relative to a control after 6 to 8 days of storage at 4°C. At room temperature, bacterial populations (aerobic plate count, coliform count, and presumptive E. coli) in raw milk treated with esterified legume proteins were inhibited by ca. 1.5 to 1.6 log relative to the control after 12 h. Supplementation of raw milk with esterified soybean protein could significantly inhibit the counts of the two inoculated pathogens (L. monocytogenesScott A and SalmonellaEnteritidis PT4), which were initially inoculated at ca. 2 log CFU ml–1, by ca. 2.4 log and 1.6 log CFU ml–1, respectively, on day 8 of storage under cold conditions. Corresponding reductions amounting to 2.7 and 1.8 log CFU ml–1were observed after 12 h of storage at room temperature. Supplementation of raw milk with esterified soybean protein (0.5%) reduced the maximum level of titratable acidity to 0.21 and maintained the pH level at 6.4 after 8 days of storage under cold conditions as compared with 4 days for untreated raw milk. Similar results were observed when raw milk was stored at room temperature for 10 h.

The aim of this study was to investigate the angiotensin I-converting-enzyme (ACE)-inhibitory activity of tryptic hydrolysates of ovine ?-lactoglobulin, and of yoghurts made by using different starters. Ovine ?-lactoglobulin (a mixture of variants A and B at a ratio of 50/50) was subjected to trypsin activity. The degree of hydrolysis of native whole ?-lactoglobulin reached 56, 72, 93 and 95% after 1, 2, 8 and 24 h, respectively. ACE-inhibitory activity of tryptic hydrolysates increased with the time of hydrolysis, yielding 85, 88 and 92% after 2, 12 and 24 h, respectively. The determination of ACE-inhibitory activity of some tryptic peptides separated by RP-HPLC and identified by mass spectroscopy showed that the more hydrophilic peptides showed the higher activity. Yoghurts obtained by fermentation of ovine milk with four different sets of starters, and their fractions soluble or not at pH 4.6 also showed an ACE-inhibitory activity. The maximum activity was obtained in the case of insoluble fractions at pH 4.6 of yoghurts made with the set of starters YC-183.Activit? inhibitrice de l?enzyme de conversion de l?angiotensine I (ECA) de peptides trypsiques de la ?-lactoglobuline du lait de brebis et de yoghourts obtenus ? partir de diff?rents levains. Une activit? inhibitrice de l?enzyme de conversion de l?angiotensine I (ECA) a ?t? recherch?e dans les peptides trypsiques de la ?-lactoglobuline du lait de brebis et dans des fractions issues de yoghourts fabriqu?s ? partir de diff?rents ferments lactiques. La ?-lactoglobuline ovine (un m?lange des variants A et B) a ?t? soumise ? une hydrolyse trypsique. Les degr?s d?hydrolyse de la ?-lactoglobuline ont atteint 56, 72, 93 et 95?% respectivement apr?s 1, 2, 8 et 24 h d?hydrolyse. L?activit? inhibitrice de l?ECA des hydrolysats trypsiques augmentait avec la dur?e de l?hydrolyse, atteignant 85, 88 et 92?% respectivement apr?s 2, 12 et 24 h. La d?termination de l?activit? inhibitrice de l?ECA de quelques peptides trypsiques s?par?s par CLHP en phase invers?e et identifi?s par spectrom?trie de masse a montr? que les peptides les plus hydrophiles pr?sentaient l?activit? la plus grande. Des yoghourts fabriqu?s par fermentation du lait de brebis ? l?aide de quatre compositions diff?rentes de levains ainsi que leurs fractions solubles ou non ? pH 4,6 pr?sentaient aussi une activit? inhibitrice de l?ECA. Le maximum d?activit? a ?t? obtenu avec les fractions insolubles ? pH 4,6 de yoghourts fabriqu?s avec le levain YC-183.

Ovine whey proteins were fractionated and studied by using different analytical techniques. Anion-exchange chromatography and reversed-phase high-performance liquid chromatography (HPLC) showed the presence of two fractions of β-lactoglobulin but only one of α-lactalbumin. Gel permeation and sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis allowed the calculation of the apparent molecular mass of each component, while HPLC coupled to electrospray ionisation-mass spectrometry (ESI-MS) technique, giving the exact molecular masses, demonstrated the presence of two variants A and B of ovine β-lactoglobulin. Amino acid compositions of the two variants of β-lactoglobulin differed only in their His and Tyr contents. Circular dichroism spectroscopy profiles showed pH conformation changes of each component. The thermograms of the different whey protein components showed a higher heat resistance of β-lactoglobulin A compared to β-lactoglobulin B at pH 2, and indicated high instability of ovine α-lactalbumin at this pH.

Spectroscopic study of interactions between esterified whey proteins and nucleic acids, at neutral pH, showed positive differential spectra over a range of wavelength between 210 and 340 nm. In contrast, native forms of whey proteins added to DNA did not produce any differential spectra. The positive difference in UV absorption was observed after addition of amounts of proteins as low as 138 molar ratio (MR) of protein/DNA, indicating high sensitivity of the applied method to detect interactions between basic proteins and DNA. UV-absorption differences increased with MR of added whey protein up to saturation. The saturation points were reached at relatively lower MR in the case of methylated forms of the esterified protein as compared to its ethylated form. Saturation of nucleic acid (2996 bp long) was achieved using 850 and 1100 MR of methylated β-lactoglobulin and of methylated α-lactalbumin, respectively. Saturation with ethylated forms of the proteins was reached at MR of 3160 and 2750. Lysozyme, a native basic protein, showed a behavior similar to what was observed in the case of methylated forms of the dairy proteins studied. However, in the case of lysozyme, saturation was achieved at relatively lower MR (700). Methylated β-casein failed to give positive spectra at pH 7 in the presence of DNA. It interacted with DNA only when the pH of the medium was lowered to 6.5, below its pI. Generally, amounts of proteins needed to saturate nucleic acid were much higher than those needed to neutralize it only electrostatically, demonstrating the presence on DNA of protein-binding sites other than the negative charges on the sugar-phosphate DNA backbones. Addition of 0.1% SDS to the medium suppressed totally all spectral differences between 210–340 nm. The presence of 5 M urea in the medium reduced only the spectral differences between 210–340 nm, pointing to the role played by hydrophobic interactions. Peptic hydrolysates of esterified and native proteins or their cationic fractions (pH > 7) produced negative differential spectra when mixed with DNA. The negative differences in UV absorption spectra were the most important in the case of peptic hydrolysates of methylated derivatives of whey proteins.

Different starch types (corn, rice, potato, corn amylose and corn amylopectin) were phosphorylated to varying degrees of substitution (DS) and tested both for acid hydrolysis during 3 h in a boiling bath and for enzymatic hydrolysis with a thermostable bacterial α-amylase (Bacillus licheniformis) for 30 min at 95 °C. Generally, phosphorylated starches showed a reduced degree of acid hydrolysis during the entire time of hydrolysis (3 h) as well as reduced susceptibility to α-amyIase hydrolysis. The enzyme action was inhibited by the presence of phosphate groups in the modified starch molecules and the extent of inhibition increased with increasing degree of phosphate substitution, regardless of the starch type. Thermoplastic films were fabricated by blending modified corn starches of different DS with polyacrylate, urea and water at a ratio of 4:5:1:50, heating for 30 min at 95 °C before casting and allowing to cool, stand and dry at room temperature. The plastic films prepared from phosphorylated corn starch showed both higher disintegration rate and a greater degradability by thermostable bacterial α-amylase than the ones prepared from non-phosphorylated starch. These new acquired properties can meet the increasing demand for biodegradable disposable plastic bags.

Different starch types (corn, rice, and potato starch, corn amylose and corn amylopectin) were phosphorylated by reaction with a mixture of mono and disodium phosphate at different molar ratios (mol phosphate/mol anhydrous glucose) under heat and vacuum. The starch granules of the modified and the native starches were microscopically examined for their sizes and morphology. The correlation between the variation in granular size of the modified starches with the extent of phosphorylation and some other physicochemical properties was studied. The granular size was generally increased while the iodine absorption capacity was decreased by phosphorylation. There were strong correlations between the variation in the starch granular size in dependence on phosphorylation and the corresponding changes in some physicochemical parameter of starch, e.g. solubility, swelling and paste clarity. This relationship was most evident in the case of phosphorylated corn amylopectin. Starch granular size can be taken as a quick indicator of the physicochemical properties of the native and modified starches.

Starch was phosphorylated by reaction with mono- and disodium hydrogen orthophosphate under dry conditions in a vacuum oven at 150-180 °C (800 mbar). Studying the different factors affecting the reaction showed that the optimal conditions for starch phosphorylation in the monoester form were: 3 h reaction time, 160 °C reaction temperature and pH 6. The different types of starch gave different degrees of substitution; and amylose bound a higher amount of phosphate than amylopectin under similar reaction conditions. Both ash content and acidity of the phosphorylated starch products increased proportionally with the increase in the degree of substitution while the pH of the different modified starch products was nearly in the same range (pH 6.55—6.75).

Different types of starch were phosphorylated to different degrees of substitution using monosodium and disodium hydrogen orthophosphate at 160 °C under vacuum. Generally, phosphation enhanced the physicochemical properties of the modified starches compared to their native counterparts. Solubility and swelling power greatly increase when phosphorylation was carried out to a low degree of substitution, while the solubility and swelling power decreased gradually by increasing the degree of substitution. However, the values of the monoesters were still higher than those of the corresponding native polysaccharides. Viscosities of different starch types except corn amylose showed the highest values at the lowest degree of substitution, when the degree of phosphation increased the viscosity values decreased. Native potato starch formed a clear paste (96% transmittance) due to the presence of phosphate groups while the paste clarity of potato starch decreased gradually by increasing the degree of phosphation. Generally, phosphorylation increased the light transmittance of the other starches investigated at the lowest degree of substitution but the clarity decreased by increasing the degree of substitution.

Limited specific hydrolysis of casein byStaphylococcus aureusV8 protease was used to produce 2% and 6.7% hydrolysates (2 and 6.7% of the peptide bonds hydrolyzed), each containing five polypeptides (by gel filtration) ranging in size from ~ 16,000 to ~1,000 daltons. The mixtures of polypeptides had substantially increased solubilities at pH 4.0–4.5, near the isoelectric point of casein. In general, the emulsifying activity index was less for the hydrolysates than for casein; the emulsion stability was higher for the 2% hydrolysate than was the emulsion from casein. Phosphorylation of zein markedly increased the water solubility of zein above and below pH 4. When the free amino acids tryptophan and/or lysine were added to zein in the presence of POC13, some amino acids were covalently bound to zein, in addition to covalent attachment of phosphate groups. Threonine did not become incorporated into zein by this method. These derivatives were much more soluble than zein above and below pH 4, the minimum solubility point. A derivative containing 0.98 mol P/mol of zein, along with 1.05% tryptophan and 0.24% lysine, had a relative growth effect onTetrahymena thermophiliof 49% that of casein, in comparison to 4.5% for unmodified zein. All the modified zeins had improved emulsifying activity indices.

Abstract: Limited specific hydrolysis of casein byStaphylococcus aureus V8 protease was used to produce 2% and 6.7% hydrolysates (2 and 6.7% of the peptide bonds hydrolyzed), each containing five polypeptides (by gel filtration) ranging in size from ∼ 16,000 to ∼1,000 daltons. The mixtures of polypeptides had substantially increased solubilities at pH 4.0–4.5, near the isoelectric point of casein. In general, the emulsifying activity index was less for the hydrolysates than for casein; the emulsion stability was higher for the 2% hydrolysate than was the emulsion from casein. Phosphorylation of zein markedly increased the water solubility of zein above and below pH 4. When the free amino acids tryptophan and/or lysine were added to zein in the presence of POC13, some amino acids were covalently bound to zein, in addition to covalent attachment of phosphate groups. Threonine did not become incorporated into zein by this method. These derivatives were much more soluble than zein above and below pH 4, the minimum solubility point. A derivative containing 0.98 mol P/mol of zein, along with 1.05% tryptophan and 0.24% lysine, had a relative growth effect onTetrahymena thermophili of 49% that of casein, in comparison to 4.5% for unmodified zein. All the modified zeins had improved emulsifying activity indices.