Percentage Of Essential Amino Acids Research Articles

Amino acid profile behavior during the fermentation of Criollo cocoa beans

The study investigated the behavior of seventeen amino acids during spontaneous (SF) and starter culture (SC) fermentation of Criollo cocoa beans from Copallín, Guadalupe and Tolopampa, Amazonas-Peru. For this purpose, liquid chromatography (UHPLC) was used to quantify amino acids. Multivariate analysis was used to differentiate the phases of the fermentation process. The percentage of essential amino acids during SC fermentation (63.4%) was higher than SF (61.8%); it was observed that the starter culture accelerated their presence and increased their concentration during the fermentation process. The multivariate analysis identified a first stage (day 0 to day 2), characterized by a low content of amino acids that increased due to protein hydrolysis. The study showed that adding the starter culture (Saccharomyces cerevisiae) to the fermentation mass increased the concentration of essential amino acids (63.0%) compared to the spontaneous process (61.8%). Moreover, this addition reduced the fermentation time (3–4 days less), demonstrating that the fermentation process with a starter culture allows obtaining a better profile of amino acids precursors of flavor and aroma.

In vitro gastrointestinal simulated digestion of three plant proteins: determination of digestion rate, free amino acids and peptide contents

ABSTRACT Cassava protein (CP), barley protein (BP) and yellow pea protein (YPP) are important nutrient and integral constituent of staple in pet foods. It is known that the digestion of proteins directly influences their absorption and utilisation. In the present work, we performed in vitro simulated gastrointestinal digestion of three plant proteins as a staple for dog and cat food. The digestion rate of CP, BP and YPP in dog food was 56.33 ± 0.90%, 48.53 ± 0.91%, and 66.96 ± 0.37%, respectively, whereas the digestion rate of CP, BP, and YPP in cat food was 66.25 ± 0.72%, 43.42 ± 0.83%, and 58.05 ± 0.85%, respectively. Using SDS-polyacrylamide gel electrophoresis to determine the molecular weight (MW) of each protein and the products of their digestion, it was revealed that MW of digestion samples decreased, and MW during the small intestine phase was lower than that during the gastric phase. Peptide sequences of digested products were identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS), and it was found that the total number of peptides in the small intestine digestion samples was higher than that in the gastric phase samples. The MW of peptides obtained from CP was within the range of 1000–1500 Da, while MW of peptides derived from BP and YPP was within the range of 400–2000 Da. In addition, free amino acids were mainly produced in the small intestine phase. Furthermore, the percentage of essential amino acids in the small intestine phase (63 ~ 82%) was higher than that in the gastric phase (37 ~ 63%). Taken together, these findings contribute to the current understanding of the utilisation of plant proteins in dog and cat foods and provide important insights into the selection and application of plant proteins as a staple in dog and cat foods.

Comparison between Amino Acid Profiling of Structural Proteins of earliest and recent omicron strain of SARS-CoV-2 and Nutritional Burden on COVID-19 patients

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has four structural proteins. Inside human host cell, it replicates, for which each requires all the structural proteins, and to generate these, entire requirement of amino acids is borne by the host. There is no data regarding amino acid profiling, variation in strains, and its actual burden on the human host. Profiling, with its therapeutic utility, was studied using genomics and proteomics of earliest Wuhan strain and was compared with the recent emerging heavily mutated variant of concern, Omicron. With each replicating SARS-CoV-2 consuming a considerable percentage of essential amino acids (EAAs), coronavirus infection causes huge burden of EAAs on the entire human body in generating billions and billions of SARS-CoV-2 and can cause depletion of body protein stores. The complete amino acid profiling of the structural proteins of SARS-CoV-2 can act as benchmark for designing the correct nutritional supplements for the management of nutritional burden on the patients with SARS-CoV-2 infection.

IMPROVEMENT OF PEARL MILLET (Pennisetum glaucum (L.) R. BR) PROLAMIN EXTRACTABILITY: CHROMATOGRAPHIC SEPARATION, CHARACTERIZATION AND FUNCTIONAL PROPERTIES

Pearl millet is a gluten free cereal resistant to drought, diseases and pests. The major protein fraction in pearl millet is prolamin the alcohol soluble fraction called pennisetin. Researches on the factors affecting pennisetin extraction and on its functional properties are still very scant. In this paper, the effect of temperature, reducing agents (β-mercaptoethanol, dithiothreitol or sodium metabisulfite) and sodium hydroxide on pennisetin extraction was assessed. Samples were characterized by protein and amino acid (AA) analysis, SDS-Page and reversed phase high-performance liquid chromatography (RP-HPLC). Pennisetin was extracted with high protein purity (90.1%) from pearl millet grain flour (PMF) using 70% aqueous ethanol containing 1% sodium metabisulfite and 0.2% sodium hydroxide at 60°C. SDS-Page confirmed pennisetin extraction and showed three subunits corresponding to the 27-, 22- and 12 kDa-pennisetins. The percentage of essential amino acids in pennisetin (68.55%) was higher than that in PMF (41.64%). The hydrophobic character of pennisetin was confirmed by the presence of 45.49% of hydrophobic amino acids. Functional properties of pennisetin and PMF were investigated. Compared to PMF, pennisetin exhibited comparable oil and water binding capacities and higher foaming capacity and emulsifying activity index but with lower emulsion stability. Pennisetin functional properties were similar or lower relatively to common used proteins of wheat, sorghum, rice or peanut. Excluding water, oil binding and foam capacities, all the functional properties of pennisetin and PMF were significantly different (p≤0.05).The findings suggest increasing the use of pennisetin and PMF as nutritional and health promoting agent for vegans and celiac patients.

Analysis and evaluation of nutritional components of <italic>Collichthys lucidus</italic> muscles from Mindong waters

<italic>Collichthys lucidus</italic> is an important small economic fish species in coastal areas of China. Because of fast growth, large catches and delicious taste, it is loved by people of Fujian and Zhejiang in China. At present, there are only a few studies of <italic>C</italic>. <italic>lucidus</italic> on nutrition. To improve the basic data of quality and nutritional composition of muscle in this species, this study analyzed and evaluated the nutrient composition of <italic>C</italic>. <italic>lucidus</italic> muscles from Mindong waters. Nutritional components in muscle of <italic>C</italic>. <italic>lucidus</italic> were tested and analyzed with routine methods. Samples of 30 wild individuals, with (12.45±1.25) cm in body length and (37.15±13.25) g in body weight, were collected from Mindong waters during the reproductive season. The results showed that contents of moisture, crude ash, crude protein and crude fat of fresh muscles were (77.70±0.21)%, (1.49±0.59)%, (17.21±0.27)% and (0.56±0.05)%, respectively. There were 17 common amino acids found in muscles, including 7 essential amino acids (except Trp). In fresh sample, the total content of amino acids was (17.01±0.11)%, the content of essential amino acids was (6.09±0.06)%; in dry sample, the total content of amino acids was (76.30± 0.44)%; the content of essential amino acids was (27.33±0.29)%; the percentage of essential amino acids in total amino acids was 35.82%; the ratio of amino acids to no-essential amino acids (EAA/ NEAA) was 66.73%. The constitutional rate of the essential amino acids accorded with the FAO/WHO standard fundamentally. According to nutrition evaluation in amino acids score (AAS) and chemical score (CS), the first limited amino acid was Val, and the second limited amino acids were Leu and Phe+Tyr; the essential amino acids index (EAAI) was 67.04. In dry sample, the content of four kinds delicious amino acids was (26.24±0.01)%, and the percentage of delicious amino acids in total amino acids was 34.40%. 27 fatty acids were found in muscle of <italic>C</italic>. <italic>lucidus</italic>. There were 12 types of saturated fatty acids, accounting for (56.48±0.10)% of the total fatty acids. The content of C18∶0 in saturated fatty acids was the highest, accounting for (32.77±0.42)% of the total fatty acids. There were 7 types of monounsaturated fatty acids, accounting for (13.22±0.12)% of the total fatty acids, and 8 types of polyunsaturated fatty acids, accounting for (30.31±0.18)% of the total fatty acids. The percentages of EPA and DHA in total fatty acids of <italic>C</italic>. <italic>lucidus</italic> were (8.23±0.14)% and (13.22±0.12)%, respectively. The composition of trace elements in muscles of <italic>C</italic>. <italic>lucidus</italic> was reasonable. Therefore, <italic>C</italic>. <italic>lucidus</italic> is delicious fish species with balanced nutrition and relatively high nutritional value, which deserves further exploitation and popularization.

Effect of Adding Fenugreek and Sprouted Fenugreek Seeds on the Chemical Properties of Wheat Flour

In this research, some chemical and physical properties of sprouted and non-sprouted fenugreek powder were studied and the proportions of its chemical components (moisture, protein, fat, ash, carbohydrates) were compared with wheat flour. The effect of sprouting on chemical properties, amino acids, minerals and the production of compound flour by substituting a molecule of flour was studied. Wheat with sprouted and non-sprouted fenugreek powder at rates of 5.2%, where the results of chemical analysis showed a high content of sprouted fenugreek from protein, moisture and ash, and a decrease in fat and carbohydrates compared with non-sprouted fenugreek. The study showed that the content of amino acids increased in the sprouted fenugreek powder compared with the non-sprouted fenugreek and wheat flour, where the percentage of essential amino acids for the sprouted fenugreek powder reached 33.8 g/100 g compared with the non-sprouted fenugreek powder and wheat flour, where the essential amino acids in both of them amounted to 27.52 g/100 g and 24.87 g/100 g, respectively, and the color acceptability decreased with a relative increase The replacement method, where the loofah manufactured from adding 2% of the sprouted fenugreek was more acceptable to the members of the evaluation committee than the addition percentage of 5%.

Direct and Knock-on Effects of Water Stress on the Nutrient Contents of Triticum aestivum (Poales: Poaceae) and Population Growth of Rhopalosiphum padi (Hemiptera: Aphididae).

To ascertain the direct effects of water stress upon wheat plants (Triticum aestivum L.) and how these effects, in turn, influence the population growth of the bird cherry-oat aphid (Rhopalosiphum padi L.), we conducted a physiological analysis of wheat seedlings grown under three different watering regimes and subsequently determined the population parameters of the aphid using the age-stage, two-sex life table. A significantly higher content of free amino acids and soluble sugars were observed in wheat seedlings exposed to drought stress compared to seedlings that were well-watered and those that were grown under waterlogged conditions. Extended phloem salivation and stylet penetration with shorter duration of sustained ingestion from phloem was observed in an electrical penetration graph (EPG) of R. padi on drought-stressed wheat seedlings. This suggested that the aphid's feeding activity, as well as nutrient intake, were impeded. The significantly higher percentage of essential amino acids found in wheat seedlings grown under waterlogged conditions promoted significantly higher fecundity and intrinsic rate of increase in R. padi populations compared to aphids fed on drought-treated or well-watered wheat seedlings. Our findings suggest that wheat seedling responses to water stress involve changes in sap composition that are responsible for altering the aphids' nutrient intake and consequently affect their population growth. From a grower's perspective, extending wheat cultivation in a rice-wheat rotation paddy field during the winter season may not be economically profitable if the fields are chronically waterlogged, since this may potentially lead to a higher infestation of cereal aphids.

Effects of Different Levels of Urea as Nitrogen Source on Chemical Composi- tion of Marine Microalgae Nannochloropsis oculata

&#x0D; &#x0D; &#x0D; Microalgae breeding media must be cost-effective, enable high growth, meet exact re- quirements and be readily available. The effect of different levels of urea [25, 50, 75, and 100%] in the growth medium on the biochemical constituents (protein, carbohydrates, lipids, fatty acids, and amino acids) of the Nannochloropsis oculata, was assessed compared to the F/2 Guillard standard medium. The obtained results revealed that the chemical constituents of N. oculata were influenced by the different levels of urea. The highest total protein was obtained by A4 medium (100% urea) (26.44%) and A3 medium (75% urea) (25.84%). The maximum percentage of essential amino acids (EAA) (51.54%) was obtained by using the A4 medium (100% urea) as compared to the control (100% F/2). The highest total lipid content was achieved by using the A1 medium (25% urea) pro- ducing (17.33 %) and A4 medium (100% urea) (16.98%). Accordingly, the highest total saturated fatty acids percentage (TSFA) of N. oculata was recorded by the A3 medium. In conclusion, the addition of urea is an excellent policy to increase chemical composition and lipid accumulation. The present study recommended taming results for aquaculture feeding through using the proposed A1 medium as a lipid promoter or A4 medium as a protein promoter.&#x0D; &#x0D; &#x0D;

The Effects of Surimi Process on Amino Acids Profile of Sphyraena jello Fish

ABSTRACT The purpose of this study was to determine the amino acids profile of Sphyraena jello surimi and minced fillet. Fresh Sphyraena jello fish with an average weight of 750 g were purchased randomly from a fisheries market in Behbahan city, southern Iran. The fillet was minced with the grinder, and then washed three times with cold distilled water. The volume of water used was 4 times the weight of the fish. In the last step, the fillet was washed in a 0.2% salt water solution, and a dewatering step was done. The samples were transferred to the Pars Biofarmacy Research laboratory for measuring the protein content and amino acids profile of surimi and minced samples, according to the AOAC method. This experiment showed that there was a significant decrease in the total protein content and the amino acids profile in obtained surimi. The essential amino acids content was lower than non-essential amino acids content. The highest percentage of essential amino acids belonged to lysine, leucine, and threonine, and the lowest was found for methionine. Among the non-essential amino acids, glutamic acid and aspartic acid had the highest percentage. Therefore, the produced surimi had amino acids contents significantly lower than the minced fillet.

Optimal Production of Protein Hydrolysates from Monkfish By-Products: Chemical Features and Associated Biological Activities.

The aim of this work was the recovery of protein substrates from monkfish waste (heads and viscera) generated in the on-board processing of this species. Initially, the effect of pH, temperature, and protease concentration was studied on mixtures of a 1:1 ratio (w/v) of monkfish heads/water. The optimal conditions of proteolytic digestion were established at 57.4 °C, pH 8.31, [Alcalase] = 0.05% (v/w) for 3 h of hydrolysis. Later on, a set of hydrolysis at 5L-pH-stat reactor were run under the aforementioned conditions, confirming the validity of the optimization studies for the head and viscera of monkfish. Regarding the chemical properties of the fish protein hydrolysates (FPH), the yield of digestion was higher than 90% in both cases and the degrees of hydrolysis and the soluble protein content were not especially large (<20% and <45 g/L, respectively). In vitro digestibility was higher than 90% and the percentage of essential amino acids ranged from 40 to 42%. Antioxidant activities were higher in viscera FPH, and antihypertensive ability was superior in head FPH. The values of number average molecular weights (Mn) of monkfish hydrolysates were 600 Da in the viscera and 947 Da in the head. The peptide size distribution, obtained by size-exclusion chromatography, indicated that the largest presence of peptides below 1000 Da and 200 Da was observed in the viscera FPH.

Effect of Various Bicarbonate Supplements on Biodiesel Production and Valuable Biochemical Components of the Marine Eustigmatophyceae Nannochloropsis oculata (Droop)

Microbial breeding media must be cost-effective, enable high growth, meet exact requirements and be readily available. The effect of different levels of sodium bicarbonate (SB) [25, 50, 75 and 100%] in the growth medium on the biochemical constituents (protein, carbohydrates, lipids, fatty acids, and amino acids) of the Nannochloropsis oculata was assessed compared to the F/2 Guillard standard medium. The obtained results revealed that the chemical constituents of N. oculata were influenced by the used level of sodium bicarbonate. The highest total protein, carbohydrate contents, and the maximum percentage of essential amino acids (EAA) (59.68 %) were obtained by using the B1 medium (25% SB) as compared to the control (100% F/2). The highest total lipid content was achieved by using the B4 medium (100% SB) producing (20.09 %). In accordance, the highest total saturated fatty acids percentage (TSFA) of N. oculata was recorded by B4 medium. However, the highest total unsaturated fatty acids percentage (USFA) was exhibited by the B1 medium. The EN 14214 and ASTM D-6751 analyzes of the production of biodiesel have shown that the produced biodiesel by B4 medium (100% SB) and the control media of high quality. In conclusion, the addition of sodium bicarbonate is an excellent policy to increase chemical composition and lipid accumulation. The present study recommended taming results foreither biodiesel production or aquaculture feeding by using proposed B4 medium as a lipid promoter or B1 medium as a protein promoter.

Features of lysine inheritance in grain sorghum hybrids of the second generation

Sorghum is one of the most important grain crops in the world. Sorghum grain is characterized by a low percentage of essential amino acids in protein, primarily lysine, which significantly reduces its feed value. There are two known mutant genes with a large lysine percentage, namely the spontaneous mutant hl gene, which was originally identified in Ethiopian lines, and the P721 gene, which is induced by ethylmethanesulfonate. The purpose of the current study was to identify the patterns of inheritance of the lysine percentage in grain sorghum hybrids of the second generation which were obtained by hybridization according to two 4x4 diallelic schemes (I - SPZS-11, Sb-126/4, 144 f/8, Zernogradskoe 204; II - ZSK-4, Belozernoe 100, Otbor 100, 34045). The hybridological analysis has established that in lysine percentage in sorghum protein there are genetic differences of 1-3 genes between the parental samples included in the hybridization. The greatest differences (3 genes) were identified between sorghum grain samples 34045 and 144 f/8. In most hybrid combinations there have been identified monogenic and digenic differences between the samples involved in hybridization. The estimation of dominance degree has identified the value of the gene manifestation, that controls lysine percentage in sorghum protein. There has been determined the dominance of both large and small values of the trait. The frequency distribution curves of the studied hybrids were within the variability of the parental forms, however, there were positive transgressions in some combinations. In the combinations Sb-126/4 × SPZS-11, Zernogradskoe 204 × SPZS-11 there have been identified the forms with a large lysine percentage in grain (more than 3.5%) for further breeding process.

Physiology and defense responses of wheat to the infestation of different cereal aphids

Cereal aphids are major insect pests of wheat, which cause significant damages to wheat production. Previous studies mainly focused on the resistance of different wheat varieties to one specific aphid species. However, reports on the physiology and defense responses of wheat to different cereal aphids are basically lacking. In this work, we studied the feeding behavior of three cereal aphids: the grain aphid, Sitobion avenae (Fabricius), the greenbugs, Schizaphis graminum (Rondani), and the bird cherry-oat aphid, Rhopalosiphum padi (Linnaeus) on winter wheat, and the physiology and defense responses of wheat to the infestation of these cereal aphids with focus on how these cereal aphids utilize divergent strategies to optimize their nutrition requirement from wheat leaves. Our results indicated that S. graminum and R. padi were better adapted to penetrating phloem tissue and to collect more nutrition than S. avenae. The harm on wheat physiology committed by S. graminum and R. padi was severer than that by S. avenae, through reducing chlorophyll concentration and interfering metabolism genes. Furthermore, cereal aphids manipulated the plant nutrition metabolism by increasing the relative concentration of major amino acids and percentage of essential amino acids. In addition, different cereal aphids triggered specific defense response in wheat. All of these results suggested that different cereal aphids utilize divergent strategies to change the physiological and defense responses of their host plants in order to optimize their nutrition absorption and requirement. These findings not only extend our current knowledge on the insect–plant interactions but also provide useful clues to develop novel biotechnological strategies for enhancing the resistance and tolerance of crop plants against phloem-feeding insects.

Characterization of Protein Hydrolysates from Eel (Anguilla marmorata) and Their Application in Herbal Eel Extracts

The enzymatic hydrolysis of fish proteins is the principle method for converting under-utilized fish into valuable products for the pharmaceutical and health food industries. In this study, three commercial enzymes (alcalase, bromelain, and papain) were tested for their ability to create eel protein hydrolysates (EPHs) from whole eel (Anguilla marmorata). Freeze-dried EPHs had almost more than 80% solubility (p &lt; 0.05) in solutions ranging from pH 2–10. The amino acid profiles of the EPHs showed a high percentage of essential amino acids, including histidine, threonine, valine, isoleucine, and leucine. The emulsion activity index (EAI) of EPH resulted as follows: alcalase group (36.8 ± 2.00) &gt; bromelain group (21.3 ± 1.30) &gt; papain group (16.2 ± 1.22), and the emulsion stability index (ESI) of EPH was: alcalase group (4.00 ± 0.34) &gt; bromelain group (2.62 ± 0.44) &gt; papain group (1.44 ± 0.09). As such, EPH has a high nutritional value and could be used as a supplement to diets lacking protein. EPH showed excellent solubility and processed interfacial properties, which are governed by its concentration. Among of them the alcalase group had the best antioxidant effect at 1,1-diphenyl-2-pyridinohydrazinyl (DPPH) radical method, determination of reducing power and ABTS test compared with other groups. EPH may be useful in developing commercial products like herbal eel extracts that are beneficial to human health.

Nutritional and Technological Characteristics of New Cowpea (&amp;lt;i&amp;gt;Vigna unguiculata&amp;lt;/i&amp;gt;) Lines and Varieties Grown in Eastern Kenya

Protein sources in the diet of people living in semi-arid land of Kenya are lacking and if available it is costly to them. In terms of safe food and a healthy food supply, cowpeas (Vigna unguiculata.) are a significant source of protein, carbohydrates, and minerals especially for poor populations in the Kenya, it is said to be poor man’s meat. The aim of this study was to determine nutritional composition of newly bred ten cowpea lines and five varieties commonly grown in Eastern Kenya of Kitui, Machakos and Makueni counties to understand their potential utilization in curbing rising food and nutrition insecurity in arid and semi-arid lands ASALs and in any other food applications in Kenya. The experiment was arranged in Completely Randomized Design (CRD) whereby proximate composition and minerals were determined using standard AOAC and AACC methods and technological characteristics checked using modified methods used by other researchers. Collected data were subjected to Analysis of Variance (ANOVA) using SAS (2006) version 9.1, mean separation was done using Tukey’s Honestly Significant Difference (HSD) method at 5% level of significance. Cowpeas composition ranged from 12.28% - 13.35% for moisture content, 49.37% - 55.74% for total carbohydrates, 2.99% - 3.34% for crude ash, 0.13% - 0.81% for crude lipids, 23.37% - 29.70% for crude protein and 1.40% - 4.34% for crude fibers. Cowpea samples recorded highest percentage of essential amino acids (60.71%) and non-essential amino acids (39.29%). Minerals ranged from 1.97 - 2.69 mg/100g for calcium, 3.23 - 3.90 mg/100g for magnesium, 205.53 - 223.30 mg/100g for sodium, 0.80 - 1.23 mg/100g for zinc, 1071.15 - 1152.62 mg/100g for potassium and 0.62 - 1.06 mg/100g for phosphorus. For technological properties, lines absorbed water equivalent to their weights and they were comparable to varieties grown in the region. From the results it showed that cowpea line IT97K-1042-3, TEXAN PINKIYE, TX123, IT85F-867-5, IT82D-889-1 and IT82D-889 have desirable attributes such as high crude protein contents, good water absorption capacities and volumetric expansion. They compared well with existing K80 variety. These cowpea lines could possibly be bred and combined into a single cowpea line and further improved by breeders to have other good properties such as higher levels of water absorption during soaking hence reduced cooking times. Therefore, this work has shown that cowpea lines developed can be used as food security crop, industrial food applications and enriching foods of low protein like in complementary foods for healthy food supply in Eastern Kenya.

Bioflocs substituted fishmeal feed stimulates immune response and protects shrimp from Vibrio parahaemolyticus infection

Fishmeal is the main source of protein in the shrimp feed industry and is normally derived from trash fish. As such, the production of fishmeal has an adverse effect on the marine environment by taking away small and juvenile fish, leading to depletion of marine species. There is a need for alternative sources of protein which will substitute fishmeal in the aquaculture industry. This study evaluated the components and nutritional efficacy of bioflocs, which were used to substitute fishmeal protein. The effect of bioflocs diets on growth performance, survival rate, and immune response in shrimp compared to normal fishmeal feed were determined. Bioflocs were harvested from the shrimp ponds (C:N ratio >12:1) at Shrimp Village, Chaiya district, Surat Thani, Thailand. The total protein in bioflocs was about 48% and the total lipid was about 5% (dried weight) and the percentages of essential amino acids (EAA) and fatty acids (EFA) in bioflocs were similar to those of fishmeal feed. Shrimp fed with the different dietary bioflocs feed regimens [% to replace fishmeal; 0% (B0), 25% (B25), 50% (B50), 75% (B75), and 100% (B100)] for 42 days revealed that all growth parameters were almost similar to those of the control shrimp (shrimp fed with normal fishmeal, B0) including final body weight, weight gain, specific growth rate, and feed conversion ratio. Remarkably, the survival rates, the levels of immune parameters, and expression of immune genes (proPO-I, PEN-4 and dicer) were significantly higher in bioflocs fed shrimp, especially in B25 and B50 shrimp. Moreover, B25 and B50 bioflocs fed shrimp showed notably increased survival rates following Vibrio parahaemolyticus (V. parahaemolyticus) infection. In conclusion, the present study demonstrates that shrimp survival and immunity are enhanced by biofiocs substituted fishmeal. Significantly, the bioflocs diets activated the immune response to prevent V. parahaemolyticus infection.

Physicochemical and Biological Properties of Eel By-Products Protein Hydrolysates: Potential Application to Meat Product Preservation

European eel by-products have been hydrolysed in order to produce novel bioactive peptides with antibacterial and antioxidant activity. Protein hydrolysates from Anguilla by-products obtained by treatment with Savinase® (PHAB-s) have high protein content than that produced with Protamex® (PHAB-p). Furthemore, both protein hydrolysates had a high percentage of essential amino acids. In addition, results indicated that PHAB-s and PHAB-p exhibited different degrees of antioxidant activities, evaluated by several antioxidant assays. Thus, PHAB-s displayed high antioxidant activity, in terms of DPPH-radical scavenging effect (IC50 = 5.2 mg/ml), β-carotene bleaching inhibitory effect (CI50 = 4.4 mg/ml) and metal chelating activity. At 10 mg/ml, PHAB-p showed the highest reducing power. Antibacterial activities of PHAB-s and PHAB-p were also evaluated. PHAB-s showed the most important inhibitory effects against seven bacterial species. The application of PHAB-s and PHAB-p on minced meat as preservative reduced the lipid oxidation and inhibited the microbial growth during chilled storage for 11 days.

Amino Acids Composition of Maggot, Earthworm, Termite and Chicken Viscera Meals Used as Proteins Sources in Fish Feeding

The present study was conducted to compare the nutritive value of animal protein sources such as maggot meal (MM), earthworm meal (EM), termite meal (TM) and chicken viscera meal (CM) for fish feeding. Amino acids composition was determined in triplicate by HPLC method. These sources were rich in crude protein (54.30-71.8%), crude fat (10.7-18.7%) and crude fibre (5.7-9.7%). The total amino acid ranged from 18.8 to 57.19 g/100 g of crude protein and the percentages of essential amino acids were 61.58% (MM), 46.21% (EM), 32.02% (TM) and 45.72% (CM). CM was the richest in total acid amino acid (Aspartic acid and Glutamic acid) than other protein sources whereas basic amino acid (Histidine, Lysine and Arginine) was higher in MM than others. Leucine has the most concentrated amino acid in MM, EM and CM whereas there is phenylalanine in TM. Predicted protein efficiency ratio (P-PER 1 and P-PER 2 ) values were (2.16, 2.14) MM, (0.68, 0.67) EM, (0.79, 0.27) TM, and (1.20, 1.13) CM respectively; isoelectric point (pI) ranged from 1.10 to 3.65; chemical index (ICh) values were: (1.07) MM, (0.24) EM, (0.11) TM and (0.61) CM. Consequently, the results showed that MM was better at 76.47%, CM in 17.64% while TM was better at 5.88%. Based on these, maggot, earthworm and chicken viscera would be recommended as alternative protein sources to fish meal, especially maggot for fish feeding.

Molecular and structural properties of three major protein components from almond kernel

Three major protein components, namely, albumin, globulin, and glutenin, were extracted from Xinjiang SC-1 defatted almond kernel powder using the Osborne classification method, and their molecular and structural properties were analyzed. SDS-PAGE indicated that the molecular weight distribution of almond kernel proteins was within the range of 21–245 kDa. The percentages of essential amino acids in the defatted almond kernel powder, albumin, globulin, and glutenin were 31.17, 24.56, 32.22, and 39.96, respectively. Among the three major protein components, almond albumin had a relatively tighter and more stable structure, resulting in a higher denaturation temperature and lower surface hydrophobicity. Spectroscopic analysis demonstrated that the almond glutenin had more aromatic amino acids distributed on its surface and was more sensitive to ultraviolet and fluorescence spectrums. This information is essential for the understanding and application of almond kernel proteins. Practical applications The present study separated the defatted almond kernel powder into its major protein components, namely, albumin, globulin, and glutenin, and the structural properties of these three major protein components were analyzed. This study aimed to provide essential information for the research and application of the almond kernel proteins.

Impact of germination on the chemical components and bioactive properties of adlay (Coix lachryma‐jobi L.) water extract

SummaryIn recent years, adlay water extract and related products have been widely consumed. This study investigated the chemical components and bioactive properties of adlay water extract at different germination stages. Glucose and maltose were significantly increased, whereas fructose was slightly decreased after germination. The contents of vitamins C and B1 in the water extract increased 1.61‐ and 2.68‐fold, respectively. The amounts of peptides, especially those with a molecular weight under 3000 Da, were significantly increased after germination. During germination, the level of total free amino acids rose from 54.09 to 128.22 μg mL−1, and the percentage of essential amino acids was elevated from 21.63% to 42.13%. Germination also substantially augmented the total phenolic content and antioxidant activity of the water extract. Moreover, the germinated adlay water extract showed higher inhibitory activity on angiotensin‐converting enzyme (ACE), xanthine oxidase and tyrosinase than the water extract of nongerminated adlay. These findings revealed that germination might be a potential way to improve the nutritional value and bioactive properties of adlay water extract.