---

Fish larvae have a high requirement of amino acid (AA) for energy production and growth. This study was aimed to increase knowledge of AA profile during feral carp larval ontogeny and estimate larval AA requirements. Larvae were collected randomly at 1, 3, 7, 11, 15, 19, 26 and 33 days post hatch for growth and AA analysis. The composition of total AA changed significantly during ontogeny. The essential AA profile of marine carp showed low correlation with rotifers (R²₌0.22). High correlation was found between dry food and early larval ages (R²≥0.7) but was lower in late stage (R²≥0.37). At day 7, when larvae were fed on rotifers, methionine seemed to be the limiting AA and when larvae were fed dry food at day 11, 15, 19, 26 and 33, arginine seemed to be the limiting AA. Larval indispensible AA profile can be used as index of the IAA requirements of carp larvae. Supplementation of larval diet used with limiting AA is one way for compensating the deficient amino acid.

---

An experiment was conducted to determine the dietary digestible lysine requirement of male and female broiler chickens (Arian) during the period from 6 to 21 days post-hatching. An amino acid-fortified basal diet containing corn and soybean meal as intact protein sources provided 20 % CP, and 3200 kcal AMEn / kg. In this experiment 150 male and 150 female chicks were allocated on the basis of BW to 12 treatments in a factorial arrangement (two sexes at six digestible lysine levels) with five replications of five chicks each in a completely randomized design (CRD). The digestible lysine levels fed were 0.85, 0.95, 1.05, 1.15, 1.25 and 1.35%. The growth rate and feed efficiency of birds fed the basal diet fortified with a surfeit level of l-Lysine-HCl were equal to those of birds fed a corn-soybean meal positive control diet. Average body-weight gain (ABWG) and gain: feed (GF) responded quadratically (P<0.05) to incremental dietary lysine addition. Subjecting the growth data to broken-line analysis indicated that the digestible lysine requirement for maximum body weight gain was 1.075% for males and 1.049% for females. The lysine requirement for maximum feed efficiency was 1.179% for males and 1.149% for females. Male chicks required a higher level of dietary lysine than females for both maximal ABWG and GF. Regardless of sex, 8.8% more digestible lysine (percentage of diet) was required for maximal GF than that needed for maximal ABWG.

---

Regarding the vast applications of amino acids  such as glutamic acid in food industry, chemistry, pharmacology and cosmetics on one and the effort to over come the problem of date wastes in  Iran on the other hand, the production of amino acids such as glutamic acid from date fruit wastes was studied. Two mutants corynebacterium glutamicum CECT690 & CECT77 were used to study of possible producing of amino acids from date wastes. Results of date fruit wastes analysis indicated that these wastes are nutritious to bacterial growth. Since date fruit wastes are complex and unknown medium for bacterial growth, in this study some effective variables on production of the amino acids using screen design (used as an experimental design) including 7 independent variables in 2 levels ( minimum and maximum) were investigated. Results of amino acids measured by high performance liquid chromatography showed that threonine and glutamic acid are produced more than other amino acids. According to the statistical  analysis, the most effective  variables on glutamic acid production are the amount of date fruit wastes, time of penicillin addition, phosphate amount and type of microorganism respectively and the least effective variables on glutamic  acid production are biotin amount, temperature and nitrogen source. Among interaction effects variables, interaction effect of date wastes amount and time of penicillin addition is the most effective of  variable on glutamic acid production. Results of statistical analysis of threonine production showed that the most effective variables on threonine production are time of penicillin addition,  the amount of date fruit wastes and type of microorganism. The results from HPLC also showed that many amino acids such as alanine, valine, lysine, proline, tyrosine, phenylalanine, leucine and isoleucine a part from glutamic acid and threonine are produced.

---

In this study the effect of three dietary treatments including; two concentrations (10⁶ and 10⁷ cells per ml) of the freshwater alga Chlorella vulgaris and one treatment of baker's yeast, Saccharomyces cerevisiae) on growth, protein and total and free amino acid composition of freshwater rotifer Brachionus calyciflorus were studied. Results showed that rotifers fed with high concentration of algae (10⁷cell/ml) had significantly higher growth rate (0.56 ± 0.03) than other treatments. Maximum density of rotifers fed high concentration (1790 ± 10.7 ind/ml) significantly was higher than low concentration (525±41.1 ind./ml) and baker's yeast +oil treatments (115±2.1 ind/ml). The crud protein of rotifers fed yeast was significantly higher than rotifers fed with low density of algae (p<0.05). Total amino acids of rotifers fed yeast, low concentration and high concentration of algae were obtained 250.66±16, 112.15±10 and 198.82±14 mg/ g of sample, respectively that there were significant difference between them(p<0.05). The highest and lowest amounts of free amino acids were observed in rotifers fed yeast (8.77±1.1) and low concentration of algae (4.04±0.3), respectively (p<0.05). Based on this study it can be concluded that rotifers fed with algae showed a higher growth rate compared with those fed the yeast, although protein and free amino acids in rotifers fed yeast were higher in compared algae treatments. In addition, treatment with high concentrations of algae, amino acids showed a relative increase in the body. 

---

Aims: Due to the high consumption of Pickhandle Barracuda, it is necessary to prepare its amino acid profile. The aim of this study was to investigate the proximate composition and amino acid profile of Pickhandle Barracuda and Yellowtail Barracuda fillet in autumn and spring.
Materials & Methods: The present experimental study was carried out on Pickhandle Barracuda and Yellowtail Barracuda in autumn and spring. The fish were equivalently divided in 2 groups of male and female in 3 clusters, each containing 7 fish. The total amino acid composition was performed by liquid chromatography. The data were analyzed by GRAPHPAD-PRISM 5 software, using unpaired T test.
Findings: In two species, moisture in autumn was higher than spring, but, compared to autumn, the amount of fat, protein, and total ash had a significant difference in spring. In spring, the essential/nonessential (E/NE) amino acid ratio and aromatic amino acids did not have any significant differences in two species, but other measures had significant differences. In autumn, the E/NE ratio and acidic amino acids did not have any significant differences. Chemical indices were more than 1 based on the needs of the adult human. In two species, Leucine showed depletion in the range of 2 to 5 years in autumn and spring.
Conclusion: Both species have a higher moisture in autumn, but the amount of fat, protein, and total ash in spring is higher than autumn. The most common amino acids in both seasons are Glutamic acid and Aspartic acid. Regarding the essential amino acids, there is no depletion in adult human necessity in two species in two seasons. Based on the needs of children aged 2 to 5 years, Leucine has depletion in both species.

---

• In this study, the apparent digestibility of protein and amino acids of  ten types of plant and animal feed ingredients as the main sources of protein was evaluated in Siberian sturgeon diet (290-250 g).

Materials and Methods: Feedstuffs included fish meal, meat and bone meal, poultry byproduct meal, blood meal, feather meal, soybean meal, rapeseed meal, wheat gluten, corn gluten and bakery yeast. The dietary treatments included: reference diet and ten different experimental rations (30% of the target feed ingredient + 70% of the reference diet). Chromic oxide was used as an indigestible marker in dietary feed. A group of 165 Siberian sturgeons stocked into 33 tanks with 500 liters volume and fed with test diets (3 replicates per diet).

• At the end of the experiment, the highest and lowest protein digestibility was observed in fish meal (92.87%) and poultry byproduct meal (59.96%), respectively. Also, the highest level of amino acid digestibility in fish meal was measured (90.9% and 88.13% for total essential and non-essential amino acids respectively). The lowest digestibility of the essential amino acids was observed in rapeseed meal (65.5%) and non-essential amino acids in poultry powder (60.68%). Conclusion: Based on the results of the present study, fishmeal, meat and bone meal, poultry byproduct meal, corn gluten and wheat gluten were identified as feed ingredients with high protein and amino acids digestibility for Siberian sturgeon.

---

Aims: the aim of this study was to extract gelatin from the skin of farmed great sturgeon at different temperatures, hydrolysis using Alcalase enzyme, and to measure molecular weight distribution of peptides, amino acid composition and antioxidant activity of hydrolysates.
 
Materials & Methods: After removing pigments and non-collagenous proteins, defatting, and swelling of triple-helix structure, gelatin was extracted at temperatures of 50, 60, 70 and 80 ºC for 6 h and then hydrolysed using Alcalase (E/S ratio of 1:20 w/w) for 3 h. Molecular weight distribution of peptides, amino acid composition and antioxidant activity of hydrolysates were determined.
 
Findings: Degree of hydrolysis reached its maximum within the first 30 min. Hydolysate from extraction temperature of 80 ºC had the highest DH.  No significant differences were found among hydrolysates with regards to amino acid composition and peptide molecular weight distribution. At of 60 ºC, the content of small peptides (< 1 kDa) and amino acids were slightly higher compared to other samples. This could influence antioxidant activity to some degree. At higher extraction temperature of gelatin, the efficacy of hydrolysates in preventing the loss in total sulfhydryl groups content was decreased (P < 0.05) while TBARS and surface hydrophobicity were not influenced (P < 0.05).
 
Conclusion: Extraction temperature of gelatin did not reveal a considerable effect on properties and antioxidant activities of the resulting hydrolysates and gelatin hydrolysates with antioxidant activity and rich in peptides with molecular weight less than 1 kDa could be produced at 50 ºC.

---

An experiment was conducted to reevaluate the digestible lysine requirement of Arian male broilers by comparing the performance of chicks fed different levels of cottonseed meal (CSM) on a total amino acid (AA) versus a digestible AA basis. Four hundred and thirty two (432) Arian male broiler chicks were allotted to 18 treatments with four repli-cates of six chicks each in a completely randomized block design in a factorial arrange-ment with two factors (two levels of digestible lysine  nine different diets). The first of the eighteen treatments was the corn and soybean meal control diet based on previously de-termined digestible lysine requirement for maximum body weight gain. Diets 2 to 5 con-tained 5, 10, 15 or 20% CSM, respectively and were formulated to contain levels of total AA equivalent to those in the first treatment. Diets 6 to 9 contained the same levels of CSM as diets 2 to 5 but the diets were formulated to be equal in digestible AA content to the first treatment. Treatments 10 to 18 were the same as treatments 1 to 9, but on the ba-sis of determined digestible lysine requirement for maximum feed efficiency. Formulating diets containing CSM on a digestible AA basis resulted in an improvement in chick per-formance compared to those formulated on a total AA basis (P<0.01). The lessening of chick performance with diets formulated on a total AA basis compared to a digestible AA basis, indicated that the previously determined digestible lysine requirement for the Arian broiler strain may be correct.

---

To Aims salt reduction and investigation, the effect of sodium chloride (NaCl) replacement by potassium chloride (KCl) on the nutrition quality and sensory assessment of fish sauce from Common Kilka (Clupeonella cultriventris) with substituting NaCl by KCl at 0%, 25%, and 50% concentration was produced during 45 days of fermentation at 37±2 C^o. The proximate composition, free amino acid profile, profile, groups, and rate of the total amino acid (TAA), indices including acid amine score, chemical score, essential amino acid (EAA) index, biological value (BV) and protein efficiency rate (PER) as well as sensory assessment, was investigated. The increase of KCl concentration led to a decrease in the sum of essential free amino acids. The most abundant amino acid in the level of 100% NaCl and 25% KCl was glutamic acid as well in the level of 50% KCl was Lysine. The highest sum of EAA and rate of EAA to TAA respectively in the level of 25 and 50% KCl recorded. Phenylalanine, Methionine, and Threonine were identified as limiting amino acids in produced fish sauces. Fish sauce with 25% KCl concentration contained a higher amount of EAA index, BV, and PER than other samples. According to sensory assessment, levels of 100% NaCl and 24% KCl were accepted by the panelists. In Conclusion, due to partly improvement in nutrition quality as well as acceptable sensory, would suggest that NaCl replaces by KCl in 25% concentration in the production of common Kilka fish sauce.

---

The effect of a selected autochthonous starter culture made up by Streptococcus thermophilus, Lactobacillus delbrueckii subsp. lactis and Lactobacillus helveticus on the microbiological and physicochemical properties of Pecorino Romano cheese during ripening was investigated. The suitability of the experimental starter culture was tested at industrial scales in cheese-making trials of Pecorino Romano. Pecorino Romano cheese manufactured by use of scotta-fermento served as control. The lactic microflora increased significantly in experimental cheeses as compared to the control and this was also accompanied by a substantial decrease of spoilage microorganisms in experimental cheeses. Free amino acids (FAAs) were more abundant in experimental cheeses, arginine+g-aminobutyric acid and leucine in particular. These differences could be likely due to a different enzymatic activity of the selected starter culture as compared to the scotta-fermento used in the control trials. Oleic (C18:1), palmitic (C16:0), butyric (C4), stearic (C18:0) and myristic (C14:0) acids were the most abundant Free Fatty Acids (FFAs) detected in both brand of cheeses at the end of ripening. Overall, the level of FFAs in experimental and control cheeses did not show significant differences, even if the average values in experimental cheeses were always slightly higher than those recorded for the control. Moreover, the average content of FFAs of Pecorino Romano was found the lowest when compared with the other Sardinian PDO cheeses; most likely the high content of sodium chloride and the low aW of Pecorino Romano influenced all the lipase activities, even those present in the rennet paste. Despite this, the employment of the selected starter culture revealed useful to improve the physico-chemical features of Pecorino Romano while preserving its tipicity.

---

Fish protein, with its higher levels of essential amino acids than land animal protein, high digestibility, and strong binding ability with other proteins as a binder, emulsifier, or dispersing agent, has prompted food industry experts to conduct extensive research into various methods for producing concentrates and powders from it. In this research, protein powder was produced from silver carp meat (Hypophthalmichthys molitrix) by washing, heat and pH-shift methods, and then the amino acid composition of the protein powder produced by different methods was compared. The results of the comparison of the average of the amino acid composition indicated that heating treatment has the maximum amount of 306.08, 409.09 mg/g of protein and 75.0% of total essential and non-essential amino acids and EAA/NEAA ratio, respectively (p<0.05). and the minimum values ​​in the EAA and NEAA indices in the pH-shift treatment with the average values ​​of 229.39 and 321.08 mg/g of protein, respectively (p<0.05) Also, the minimum ratio of EAA/NEAA was assigned to the washing treatment with an average value of 0.68% (p<0.05). On the other hand, according to the general results and in line with determining and classifying the optimal treatment, it can be reported that heat treatment among other treatments, Due to the maximum amounts of total essential and non-essential amino acids and the EAA/NEAA ratio and the amount of Glu and Asp amino acids (two important umami amino acids),

---

Aspergillus has many species that are important in medicine, agriculture, and various industries. The genus has 446 identified species, which are difficult to distinguish from each other with the use of morphological characteristics. Xylan 1,4-beta-xylosidase is an enzyme that catalyzes the hydrolysis process of xylose in xylooligosaccharides and is produced by different species of Aspergillus. This research was conducted with the aim of a bioinformatics study of the gene region related to this enzyme and to evaluate its similarities and differences in some Aspergillus species. The results showed that this gene region, due to the presence of conserved motifs, was able to distinguish some species studied in this research.

---

Arginine (Arg) requirements of male broilers (Ross 308) reared at high altitude (2100 m above sea level) during the 1-to 3-week period was estimated in a graded supplementation method, in which six diets (230 g kg-1 CP and 3200 Kcal ME kg-1) with Arg increments of 1.25 g kg-1 were applied to four pens of fifteen birds each. Dietary Arg content of the experimental groups ranged from 10 g kg-1 (80% of the NRC recommendation) to 16.25 g kg-1 (130% of the NRC recommendation). Body weight gain, feed: gain ratio, and plasma nitric oxide (NO) concentration were determined as response criteria. Arginine requirements for maximal body weight gain and optimal feed: gain during the 21 days under study were estimated to be 15.3, and 15.1 g kg-1 of diet, respectively. The estimated Arg requirement based on the response in plasma NO was 15.6 g kg-1. In conclusion, broilers receiving dietary Arg of 15 g kg-1 had the best performance. Data obtained for the individual factors are by far the highest values reported for Arg requirements.

---

---

In present study, the effect of the percentage of meat in the first stage (three levels of 30, 60% and 90%) and replacement of dried milk powder with soybean meal in the second stage on amount of acrylamide formed in grilled beef and chicken burgers (containing 60% meat) was investigated. Also, total sugar, protein, moisture and sensory characteristics of burgers were determined. The results indicated that the amount of acrylamide in chicken burgers was significantly less than that of beef burgers (p <0.05). The highest and the lowest amounts of formed acrylamide related to meat burger 60% (66.03 μg/kg) and chicken burger 90% (26.54 μg/kg), respectively. Further, the increase of the beef and chicken meat content from 30 to 60% led to increase in acrylamide while increasing from 60 to 90% resulted in decrease in the amount of formed acrylamide. The total sugar content of chicken meat burgers was significantly higher than that of beef burgers while their protein content was lower (p<0.05). The results also indicated that increasing replacement of dry milk powder caused to increase in amount of formed acrylamide in the burgers. The highest and the lowest amounts of acrylamide in the second stage related to the beef burger contains 16% dried milk powder (69.25 µg/kg) and chicken burger containing 8% dried milk powder (40.35 µg/kg). It seems the lowest amount of acrylamide in burgers would be formed in present of the chicken burgers containing 90 percent meat without dried milk powder

---

Caviar is one of the valuable and most popular fish products all over the world that are obtained from sturgeons. Nowadays, the wild resources of these fishes are diminished, therefore, to meet the demand for the product, farming sturgeons has been considered. The chemical composition and the amino acids profiles of the wild and farmed roe obtained from beluga (Huso huso) were compared and the results have indicated that the amount of glutamine, serine, alanine, methionine, and lysine in the wild roe were higher than the farmed one (P< 0.05). The total amino acids (TAAs) and the ratio of essential amino acids (EAAs) to TAAs and EAAs to non-essential amino acids (N-EAAs) in the samples from the wild and farmed roe were similar (P> 0.05). The protein efficiency ratio (PER) and chemical score in farmed and wild roe were also similar (P> 0.05). The results showed that the farmed roe was similar to the wild one based on chemical composition, chemical score, PER, EAAs/TAAs and EAAs/N-EAAs. According to the results, farmed roe can be a good substitution for wild beluga roe (Huso huso).

---

In this research, two field crops(Zea mays L. and Phaseolus vulgaris L.), two medicinal plants(Hyssopus officinalis L. and Nigella sativa L.)and two weeds(Amaranthus retroflexus L. and Taraxacum officinale F. H. Wigg) were separately treated with three concentrations of SiO₂ nanoparticles (400, 2,000, and 4,000 mg L^-1). The effects of these treatments on morphological and biochemical characteristics of the plants were assessed, including germination, root and shoot length, root and shoot fresh weight, root and shoot dry weight, photosynthetic pigments, total carbohydrates, total protein, total amino acid, and proline content. In the crops and medicinal plants, 400 mg L^-1 SiO₂ NPs significantly increased seed germination, root and shoot lengths, fresh weights (except for H. officinalis) and dry weights, photosynthetic pigments, total protein, and total amino acid (except for H. officinalis). In weeds, as SiO₂ NP concentration increased from 400 to 4,000 mg L^-1, germination, root and shoot lengths, fresh and dry weights, and photosynthetic pigments as well as total protein decreased. Total carbohydrates in all plants decreased significantly, except for A. retroflexus at 400 mg L^-1 SiO₂ NPs. In all plant species, with increasing SiO₂ NP concentration, proline content increased significantly. According to these results, a lower concentration of SiO₂ NPs can have beneficial effects on morphological, physiological, and biochemical characteristics of plants.

---

In this study, the effect of enzyme type (alcalase and pepsin) and process time (50-300 minutes) on the degree of hydrolysis and antioxidant indices including free radical scavenging of DPPH, ABTS, hydroxyl, reducing power, and chelating activity of Iron and copper ions were evaluated for navy bean protein (Phaseolus vulgari L.). Also, the composition of amino acids (hydrophobic and antioxidants types) and structural properties (FTIR) of primary protein and hydrolysates were investigated. The results showed that enzymatic hydrolysis improves antioxidant properties. Also, the composition of amino acids has a significant effect on antioxidant activities. On the other hand, the type of enzyme and the time of the hydrolysis process affected the degree of hydrolysis and the antioxidant activity of the hydrolysates. Thus, the highest percentage of free radicals scavenging of DPPH (82.4%), ABTS (58.3%), reducing power (0.97), hydroxyl radical scavenging (57.5%), and chelation of Fe (53.7%) and Cu ions (12.1%) were affected by the type of enzyme and process time. Among different treatments, the highest value of these indices (except copper ion chelating) was related to hydrolysates with alcalase. Structural properties of white bean protein were evaluated and enzymatic hydrolysis caused changes in the amide regions (I and II) as well as exposure to some hydrophobic-buried groups. The results of this study indicated the positive effect of enzymatic hydrolysis on the production of antioxidant hydrolysates that can be used in the food industry.

---

The present work aimed to study the effect of enzymatic hydrolysis of sarcoplastic and myofibrillar proteins from pangasius sutchi fish on the chemical compositions, the solubility, degree of hydrolysis (DH), peptide content and amino acid compositions was evaluated and their molecular weight recorded. The fish sarcoplasmic protein hydrolysates (SPHs) and myofibrillar protein hydrolysates (MPHs) were produced using three types of proteases: papain, alcalase and flavourzyme. Physicochemical properties of proteins and molecular weight were investigated. Results indicated that type of protease affected the degree of hydrolysis (DH), where all of the enzymes showed high rate of hydrolysis during the first hour, and then gradually decreased. The type of enzyme and the extent of the DH greatly influenced the amino acid residue composition and the molecular weight of the protein hydrolysates. Different amino acid composition of proteins and their hydrolysates was observed. The soluble protein and peptide content of hydrolysates significantly increased by the increase in time of incubation. The high amount of hydrophobic and aromatic amino acids in the SPH and MPH can enhance the biological activities of the peptides. Results suggest that the protein hydrolysates derived from patin may be used in functional food and supplements.
 

---

 In view of the increasing sulphur deficiency in Poland’s soils, in 2007-2010, a field experiment was performed with white mustard (Sinapis alba L.) in Haplic Luvisol with low sulphur content (mean – 9.4 mg kg^-1). The aim of the research was to evaluate the effect of varied sulphur application methods (foliar and pre-sowing soil application), forms (elemental and ionic), and rates (0, 20, 40, 60 kg S ha^-1) on the content of protein in mustard seeds, as well as on its amino acid and fraction composition. The research showed that of all the studied factors, the sulphur application rate affected the protein content the most. As compared with the control, sulphur application increased the overall sums of essential and dispensable amino acids in the mustard seeds as well as their quantitative ratio. The biological protein value indices (Chemical Score and Essential Amino Acid Index) point to a clearly positive effect of sulphur on the amino acid composition of the protein, including sulphur-containing methionine, an amino acid limiting protein biosynthesis. The sulphur rate significantly affected the content of all the protein fractions assayed, except for glutelins.