Analysis Of Amino Acid Profiles Research Articles

Protein Fractions of Jackfruit Leaf Flour and Protein Concentrate: Amino Acid Profile, Functional Properties and Thermal Analysis

Protein Fractions of Jackfruit Leaf Flour and Protein Concentrate: Amino Acid Profile, Functional Properties and Thermal Analysis

Amino Acid Profile and Proximate Analysis of Fermented African Locust Bean (Parkia biglobosa) Seeds

Amino Acid Profile and Proximate Analysis of Fermented African Locust Bean (Parkia biglobosa) Seeds

Impact of alkaline solution, carbohydrase and biomass:solvent on extraction efficiency, and protein and amino acid profiles of Palmaria palmata protein extracts

The impact of using different alkaline solutions, carbohydrases and changing the biomass to solvent volume ratio (biomass:solvent) on protein content, protein and biomass yield recovery in protein enriched extracts from Palmaria palmata (red seaweed) was studied. Protein extraction with alkaline solutions, i.e., NaOH, KOH, Ca(OH)2 and Na2CO3 (at 0.12 M) along with (and without) carbohydrases B, BD and L (containing xylanase, a mixture of xylanase and cellulase, and a combination of cellulase, xylanase and polygalacturonase activities, respectively) was assessed. Principal component analysis was used to assess correlations (if any) between the different alkaline solvents, carbohydrases and changing biomass:solvent on extraction efficiency. The highest protein content (56.64 ± 0.43 % (w/w)) was obtained using KOH assisted extraction with carbohydrase BD. The highest protein and biomass yield recoveries (70.65 ± 1.38 and 21.99 ± 0.43 % (w/w), respectively) were obtained on extraction using NaOH assisted with carbohydrases BD. Electrophoretic, amino acid profile and amino acid score analyses displayed differences depending on the alkaline solvent used for protein extraction. Appropriate selection of the alkaline solvent, carbohydrase and biomass:volume combination during protein extraction can contribute to the production of compositionally enhanced high-quality protein concentrates from P. palmata.

Exploring the potential of germination and ozone treatment to improve the nutritional profile and functional properties of amaranth grains

SummaryThis study investigates the impact of germination and ozone treatment on the nutritional and bioactive properties of grains of two amaranth varieties. The study focused on the proximate composition, antioxidant activity, phenolic and flavonoid content, and amino acid profile of untreated and treated grains of two amaranth varieties. Germination significantly increased the protein content by 18.5%, crude fibre by 25.7%, and total phenolic content by 34.2% compared to the control. Ozone treatment further enhanced these properties, with a notable increase in antioxidant activity by 41.8% and total flavonoid content by 29.6%. The amino acid profile analysis revealed a significant rise in essential amino acids, particularly lysine, which increased by 22.4% following the combined treatment. These findings suggested that the combined application of germination and ozone treatment significantly enhances the nutritional quality and bioactive properties of amaranth, making it a superior ingredient for functional food products. The results indicated that these processes could be effectively utilised to boost the health benefits of amaranth, contributing to the development of nutrient‐rich food products.

Physicochemical composition and amino acid profile of the beverage of Ungurahua (Oenocarpus bataua) from the Amazonian Region of Ecuador.

Oenocarpus bataua, also known as Ungurahua, is a palm species indigenous to Ecuador's Amazon region. The fruit is used for oil extraction and beverage production. This research aimed to evaluate a beverage made from O. bataua by characterizing its physicochemical properties, amino acid profile, formulation, and sensory and microbiological properties. The research employed quantitative, exploratory, and experimental methodologies utilizing a bifactorial design (3 × 2). This research investigated the effect of cooking and the type of sweetener on the quality of sweetened products. Six treatments were applied, and sensory analysis was performed to determine the optimal treatment. The most effective treatment was a2b2 (cooked for 30 min at 65 ±3°C and sweetened with panela). Upon further analysis, this treatment had a moisture content of 94.7%, ash content of 0.85%, protein content of 0.59%, ethereal extract EE of 2.18%, fiber content of 0.80%, non-nitrogenous extract-ENN of 0.85%, pH of 4.37, Brix of 1.80°, and titratable acidity of 1.92%. A comparison of O. bataua beverages with similar beverages indicated their acceptable nutritional value. Amino acid profile analysis showed the presence of 10 amino acids, of which 8 were essential, and 10 were non-essential. Histidine had the highest concentration in the beverage, with an average of 77%. To ensure the safety and quality of the beverage, a microbiological analysis was performed in compliance with NTE-INEN 3028 standards. No mesophilic aerobes, Salmonella spp., or total coliforms were detected. Therefore, the proposed beverage is safe and nutritionally valuable because of its high amino acid content, balanced physicochemical composition, and sufficient microbiological composition.

Study of Amino Acid Profile and Solubility of Pea Protein Isolate for the Production of Beverages for Psychiatric Patients

Abstract Excessive intake of saturated fatty acids and physiologically imbalanced amino acids worsens the patient’s psychotic condition, creating the risk of developing psychosis and other comorbidities. Therefore, to ensure the optimal amount of amino acids and improve the psychotic state, pea protein isolate is an alternative to nutritional supplementation. The aim of the study was to analyse the amino acid profile of pea protein isolates and their solubility to evaluate their potential for the development of beverages for patients with psychiatric disorders. In the study, the amino acid profile analysis of organic and conventional pea protein isolates was performed using high performance liquid chromatography mass spectrometry. To evaluate solubility, pea protein isolates were treated in an ultrasonic bath and at different pH concentrations. The results showed that organic pea protein isolate showed a higher composition of essential amino acids (41.27%) and semi-essential amino acids (8.37%) than conventional pea protein isolate. Organic pea protein isolate was able to provide a more appropriate amino acid composition to meet the amino acid needs of patients with psychiatric disorders. Organic and conventional pea protein isolates had higher solubility in the ultrasonic bath of 20 min and in the alkaline environment. The solubility between the two pea protein isolates was not significantly different, but the ultrasonic bath treatment and different pH concentrations were significant, which gave insight and further application in beverage production.

Comparative Analysis of Serum Amino Acid Profiles in Patients with Myasthenia Gravis and Multiple Sclerosis.

Background: Multiple sclerosis (MS) and myasthenia gravis (MG) are autoimmune diseases that attack the central nervous system (CNS) and the neuromuscular junction, respectively. As the common pathogenesis of both diseases is associated with an autoimmune background and the involvement of T and B lymphocytes, the overlapping of selected clinical symptoms may cause difficulties in the differential diagnosis of both diseases. Methods: The aim of the study was to use Liquid Chromatography-Electrospray Ionization-Mass Spectrometry (LC-ESI-MS/MS) in conjunction with multivariate statistical analyses to examine the changes in amino acid metabolic profiles between patients with MG, MS, and a control group. Results: Comparative analysis of amino acids (AA) between patients with MG, MS, and within the control group allowed for the identification of statistically significant differences in the amino acid profile. Comparing the patients (patients with MS and MG) with the control group, and after taking the results of multiple tests into account, it was observed that amino acids such as ARG, PRO, TRP, CIT were significantly different between the groups. When considering the comparison between the AA concentrations in MS and MG patients, we found three AAs that were significantly different in the MS and MG groups, after correcting for multiple testing (CIT, GABA, and AAA). Higher concentrations of amino acids that showed significant differences were observed in patients with myasthenia gravis. Conclusions: Our results have indicated AAs that may prove valuable for improving the diagnostics of MS and MG patients. To better assess the potential utility of these markers, their performance requires further validation in a larger study group and limitation of possible confounding factors, e.g., medications and diet.

Nutritional and Biochemical Analysis of Locally Produced Wine from a Blend of Banana (Musa sapientum) and Date Palm Fruit (Phoenix dactylifera L.)

Background: Wine is a low-alcohol beverage made from fresh grapes or grape juice through partial or complete fermentation. Wine contains many nutrients necessary for the human body, such as sugar, vitamins, amino acids, mineral elements, polyphenols etc. Objective: This project aimed at analysing the nutritional and biochemical composition of locally produced wine from a blend of banana and dates palm fruit. The study includes determining the proximate, phytochemical, mineral, physicochemical, and amino acid profiles. Methods: The method involves heating a crucible dish to eliminate moisture, determining fat content, defatting the sample, determining ash, and determining crude protein. The phytochemical analysis includes tests for saponin, flavonoid, alkaloid, and tannin. Mineral analysis was carried using an atomic absorption spectrophotometer, while physicochemical analysis includes alcohol, pH, and temperature measurements as well as determination of amino acid profile analysis of banana-date palm wine. Results: The proximate analysis revealed high moisture content (97.87%), suggesting a good source of fruit wine production. The wine contains low crude fibre (1.01%), low crude protein (0.14%), Ash content (0.49%) and low crude lipid (0.58%). The wine also contains antioxidant and anti-inflammatory properties. Physicochemical analysis revealed an average pH of 4.62 to 4.71, with sugar concentration decreasing daily over four days and two mineral elements were reveal which are potassium and phosphorus. The amino acid profile analysis of banana-date palm wine reveals that it contains both essential and non-essential amino acids. The essential amino acids include isoleucine, methionine, histidine, and phenylalanine, non-essential amino acids include glutamic acid, asparagine, proline, and cysteine. Conclusion: The findings of this study suggest that a blend of Banana (musa sapientum) and date palm fruit (Phoenix dactyliferal) wine has a unique pleasant aroma, and may have the potential to provide both essential and non-essential amino acids, provide other nutrients that are important for normal physiological function of the body.

Comprehensive biochemical analysis and nutritional evaluation of fatty acid and amino acid profiles in eight seahorse species (Hippocampus spp.)

Seahorses are increasingly recognized for their nutritional potential, which underscores the necessity for comprehensive biochemical analyses. This study aims to investigate the fatty acid and amino acid compositions of eight seahorse species, including both genders of Hippocampus trimaculatus, Hippocampus kelloggi, Hippocampus abdominalis, and Hippocampus erectus, to evaluate their nutritional value. We employed Gas Chromatography-Mass Spectrometry (GC-MS) and High-Performance Liquid Chromatography (HPLC) to analyze the fatty acid and amino acid profiles of the seahorse species. GC-MS was used to detect 34 fatty acid methyl esters, while HPLC provided detailed amino acid profiles. GC-MS analysis demonstrated high precision with relative standard deviations (RSDs) generally below 2.53 %, satisfactory repeatability (RSDs from 6.55 % to 8.73 %), and stability (RSDs below 2.82 %). Recovery rates for major fatty acids ranged from 98.73 % to 109.12 %. HPLC analysis showed strong separation of amino acid profiles with theoretical plate numbers exceeding 5000. Precision tests yielded RSDs below 1.23 %, with reproducibility and stability tests showing RSDs below 2.73 % and 2.86 %, respectively. Amino acid recovery rates ranged from 97.58 % to 104.66 %. Nutritional analysis revealed significant variations in fatty acid content among the species. Female H. erectus showed higher levels of hexadecanoic acid and saturated fatty acids, while male H. abdominalis had lower concentrations of n-3 full cis 4,7,10,13,16,19-docosahexaenoic acid (DHA). Total lipid yields varied from 3.2491 % to 12.3175 %, with major fatty acids constituting 17.9717 %–74.6962 % of total lipids. In conclusion, this study provides essential insights into the fatty acid and amino acid composition of seahorses, supporting their potential as valuable dietary supplements. The differences between genders in specific fatty acids suggest a nuanced nutritional profile that could be exploited for targeted dietary applications. Further research is needed to explore the seasonal and environmental variations affecting seahorse biochemical composition.

Analysis of carcass traits, meat quality, amino acid and fatty acid profiles between different duck lines

To investigate the effect of genetic selection on meat quality in ducks, twenty of each fast growth ducks (LCA) and slow growth ducks (LCC) selected from F6 generation of Cherry Valley ducks (♂) x Liancheng white ducks (♀) were analyzed for carcass characteristics, meat quality (physicochemical and textural characteristics), amino acid and fatty acid profiles at 7 wk. Results showed that live body weight, slaughter weight, eviscerated yield and abdominal fat percentage of LCA were significantly higher than those in LCC ducks (P < 0.01). Moreover, the average area and diameter of myofiber were larger in LCA than LCC ducks (P < 0.01). The breast and thigh muscles of LCA exhibited significantly lower water holding capacity and thermal loss compared with LCC ducks (P < 0.01). In addition, the content of nonessential amino acids (Glu, Asp, and Arg) in breast muscles and Asp, Ser, Thr, and Met in thigh muscles was higher in LCC than LCA ducks (P < 0.05). The proportion of polyunsaturated fatty acids (PUFA) in breast muscles of LCC was higher than LCA ducks (P < 0.05). However, the content of saturated fatty acids (SFA) in breast and thigh muscles of LCA was higher compared with LCC ducks (P < 0.05). The proportion of monounsaturated fatty acids (MUFA) in thigh muscles was significantly higher in LCC compared with LCA ducks (P < 0.01). Finally, multiple traits were evaluated by applying principal component analysis (PCA) and the results indicated that PUFA and SFA in breast muscles of LCA played important roles in meat quality, followed by Warner-Bratzler shear force (WBSF) and MUFA. However, water holding capacity (WHC) had a dominant effect in meat quality of thigh muscles in both LCA and LCC ducks.

Metabolomic Analysis of Amino Acid and Organic Acid Profiles in Tissue From Ovarian Cancer Patients Using High-Performance Liquid Chromatography-Tandem Mass Spectrometry (HPLC-MS/MS) and Gas Chromatography-Tandem Mass Spectrometry (GC-MS/MS)

Targeted metabolomics studies on organic acids (OAs) and amino acids (AAs) were performed to search for biomarkers for ovarian cancer progression. Simultaneous AA profiling analysis method was developed through LC-MS/MS. Under optimal conditions, method showed good linearity (r ≥ 0.998) with limits of detection (LOD) ≤ 0.22 ng/mL and limits of quantification (LOQ) of ≤0.72 ng/mL. Repeatability varied from 1.4 to 17.3 relative standard deviation (%RSD) and accuracy varied from −20.6% to 12.1% relative error (% RE). Twenty-six AAs and 13 OAs were detected in the analyses of ovarian tissue from patients with benign ovarian tumors (BOT), borderline tumors (BT), and ovarian serous carcinoma (OSC). Star pattern recognition analysis was performed by normalizing each group to the BOT group. The star symbol plots in the BT and OSC groups were distinct and easily distinguished from those in the BOT group. The BT and the OSC groups exhibited higher 3-hydroxybutyric acid and lactic acid levels, lower pyruvic acid and OA levels in the TCA cycle, and alterations in AA metabolic patterns in comparison to the BOT group. Especially, citrulline and leucine were significantly reduced, while fumaric acid and malic acid significantly increased in the OSC group compared to the BT group. The BT and the OSC groups were completely separated in orthogonal partial least squares-discriminant analysis (OPLS-DA) and heatmap analysis. These findings, elevated ketone body levels, increased anaerobic glycolysis, reduced energy production related to mitochondrial dysfunction in the TCA cycle, and AA metabolic patterns associated with the impaired antioxidant system, may explain the characteristic metabolic reprogramming and Warburg effect related to the progression of the OSC into malignancy.

Characterization and comparative effect of drying process on antioxidant activity over Chilean sea cucumber (Athyonidiun chilensis)

Chilean sea cucumber, Athyonidium chilensis, has both a high nutritional value and a high economic potential to increase the trade of other marine products. Currently there is a minimal commercialization of sea cucumber within Chile, and it is sold exclusively to China in dry or frozen forms where it is then used nutraceutical, cosmetic and nutricosmetic products marketed mostly in Asia. The objective of this study was to determine the nutritional, heavy metals, mineral and amino acids contents of Chilean sea cucumber (eviscerated and ground form) and compare its antioxidant capacity following three different drying processes. The results showed that A. chilensis had very high level of protein contain (68.17%), ash (17.41%), fiber (13.22%), and very low fat and carbohydrate contents. The antioxidant activity measured by ORAC (oxygen radical absorbance capacity) was between 6676.34 and 10,321.30 μmol TE(Trolox equivalents)/100 g, depending on the drying process used. Amino acid profile analysis showed that total amino acids in Chilean sea cucumber was 60.3 g/100 g protein. The information obtained illuminates the antioxidant capacity and amino acid profile that has not previously been reported for Athyonidium chilensis, which indicates that this species has a competitive commercial value for use in food or nutraceutical products, when compared to similar sea cucumbers found on the international market.

Genetic stability, amino acid, and polyamine profile analyses in radiata pine somatic embryos maturated at high temperatures

Genetic stability, amino acid, and polyamine profile analyses in radiata pine somatic embryos maturated at high temperatures

Comparative Analysis of Amino Acid Profile of Tenualosa Ilisha and Catla Catla and Their Potential Contribution to Recommended Nutrient Intake

Objective: The current study aimed to determine the amino acid profiles and proximate compositions of two commonly consumed fish species of Bangladesh: Tenualosa ilisha and Catla catla, commonly known as Hilsha, the national fish of Bangladesh and Catla, respectively. Methodology: The fish samples were collected from two wholesale fish markets (ghaats) in Dhaka city, the capital of Bangladesh. The Amino Acid content of the selected samples was analyzed by an amino acid analyzer. Fourteen amino acids (eight essential and six non-essential) could be detected by the analyzer. Results: In the case of the essential amino acid content of the samples, threonine, valine, isoleucine, histidine, and lysine content was greater in the Hilsha fish than that of Catla. On the other hand, methionine, leucine, and phenylalanine content were higher in Catla than that in Hilsha. All six non-essential amino acids were found in greater amounts in Hilsha. Concerning the potential contribution (%) of the selected samples to the daily recommended nutrient intake (RNI) of essential amino acids in children (5-10 years), Hilsha fish potentially contributes (&gt;50%) to the daily RNI of threonine, methionine, and lysine and Catla fish potentially contributes (&gt;50%) to the daily RNI of methionine and lysine. In regards to the adult’s RNI, Hilsha potentially contributes (&gt;50%) to the daily RNI of methionine and lysine but Catla was found to contribute potentially (&gt;50%) to the daily RNI of methionine only. Conclusion: Both of the samples were found to be a substantial source of protein and essential amino acids to significantly contribute to the daily RNI of essential amino acids concerning children (5-10 years) for growth and adults for maintenance. Bioresearch Commu. 10(1): 1371-1377, 2024 (January)

Phenotypic, nutritional, and bioactive characteristics of Pluerotus pulmonarius grown on three different substrates

This paper investigated the impact of substrates on the physical and biochemical properties of Pluerotus pulmonarius. The mushroom was grown on three different substrates: sawdust (sds), palm bunch (pbs) and corn cob (ccs), in the cropping house for 28 days for fruiting bodies to emerge. The phenotypic properties of the mushrooms grown from the three different substrates designated as sdm, pbm, ccm, were measured. Proximate composition, phytoconstituents and antioxidant activities were determined using standard methods while the amino acid profile and mineral analysis were determined using HPLC and ICP-AES, respectively. From our results, the electrical conductivity of the substrates was high. The mushroom grown on pbs supported the growth and yield of the mushroom most while ccm produced mushroom with the least phenotypic attributes. The mushrooms grown on all the substrates had high crude protein content and low-fat content, however pbm had the highest crude protein content of 25.19%. Amino acid profile showed all the essential amino acids in all the mushrooms. Interestingly, sdm had the highest (P < 0.05) amino acid concentration compared to pbm while ccm had the least. Mineral analysis showed the presence of essential trace minerals including Fe, Zn and Cu which were either absorbed or bioaccumulated by the mushrooms especially those grown on sds and pbs. The substrates pbs (Fe: 537.12 ppm), and ccs (Cu: 11.37 ppm, Zn: 59.33 ppm) had the highest (P < 0.05) concentration of the minerals. The phytochemical composition of the mushrooms was relatively low: phenolics (1.27 mg/g), flavonoids (0.87 mg/g), tannins (1.08 mg/g), saponins (1.49 mg/g), alkaloid (0.43 mg/g). The mushrooms showed antioxidant activity and the highest activity was seen with ABTS* free radical scavenging using pbm (82.21 mmolTEAC/g). The mushrooms inhibited cholinesterase and lipase activities indicating possible use in therapeutics. Our data indicates that pbs provided the most support and nourishment that significantly impacted the physical and, in some degree, the biochemical characteristics of the mushroom followed by sds. Our data together suggest that pbs maybe the most viable in mushroom growth among all tested substrates.

Comparative Analysis of Amino Acid Profiles in Patients with Glioblastoma and Meningioma Using Liquid Chromatography Electrospray Ionization Tandem Mass Spectrometry (LC-ESI-MS/MS)

Brain tumors account for 1% of all cancers diagnosed de novo. Due to the specificity of the anatomical area in which they grow, they can cause significant neurological disorders and lead to poor functional status and disability. Regardless of the results of biochemical markers of intracranial neoplasms, they are currently of no diagnostic significance. The aim of the study was to use LC-ESI-MS/MS in conjunction with multivariate statistical analyses to examine changes in amino acid metabolic profiles between patients with glioblastoma, meningioma, and a group of patients treated for osteoarthritis of the spine as a control group. Comparative analysis of amino acids between patients with glioblastoma, meningioma, and the control group allowed for the identification of statistically significant differences in the amino acid profile, including both exogenous and endogenous amino acids. The amino acids that showed statistically significant differences (lysine, histidine, α-aminoadipic acid, phenylalanine) were evaluated for diagnostic usefulness based on the ROC curve. The best results were obtained for phenylalanine. Classification trees were used to build a model allowing for the correct classification of patients into the study group (patients with glioblastoma multiforme) and the control group, in which cysteine turned out to be the most important amino acid in the decision-making algorithm. Our results indicate amino acids that may prove valuable, used alone or in combination, toward improving the diagnosis of patients with glioma and meningioma. To better assess the potential utility of these markers, their performance requires further validation in a larger cohort of samples.

Impact of Different Light Conditions on the Nitrogen, Protein, Colour, Total Phenolic Content and Amino Acid Profiles of Cultured Palmaria palmata

The impact of different light conditions during culture on the nitrogen, protein, colour, total phenolic content (TPC) and amino acid profile of Palmaria palmata biomass was investigated. P. palmata was cultured using different light regimes, i.e., white (1 and 2), red, blue and green over 12 days. A significant decrease (p &lt; 0.05) in total nitrogen (TN), non-protein nitrogen (NPN) and protein nitrogen (PN) was observed on day 6 while an increase was observed on day 12 in P. palmata samples cultured under blue light. The protein content (nitrogen conversion factor of 4.7) of the initial sample on day 0 was 15.0% (w/w) dw whereas a maximum protein content of 16.7% (w/w) was obtained during exposure to blue light following 12 days culture, corresponding to an 11.2% increase in protein content. Electrophoretic along with amino acid profile and score analyses showed light-related changes in protein composition. The lighting regime used during culture also influenced the colour parameters (lightness L*, redness a*, yellowness b* and colour difference ΔE) of milled algal biomass along with the TPC. Judicious selection of lighting regime during culture may allow the targeted production of sustainable high-quality proteins from P. palmata.

Molecular Diversity of Rice Yellow Mottle Virus in Uganda and Relationships with Other Strains from Africa.

Rice yellow mottle virus disease, caused by Rice yellow mottle virus (RYMV), is the most important disease of lowland rice in Uganda. However, little is known about its genetic diversity in Uganda and relationships with other strains elsewhere across Africa. A new degenerate primer pair that targets amplification of the entire RYMV coat protein gene (circa 738 bp) was designed to aid virus variability analysis using RT-PCR and Sanger sequencing. A total of 112 rice leaf samples from plants with RYMV mottling symptoms were collected during the year 2022 in 35 lowland rice fields within Uganda. The RYMV RT-PCR results were 100% positive, and all 112 PCR products were sequenced. BLASTn analysis revealed that all isolates were closely related (93 to 98%) to those previously studied originating from Kenya, Tanzania, and Madagascar. Despite high purifying selection pressure, diversity analysis on 81 out of 112 RYMV CP sequences revealed a very low diversity index of 3 and 1.0% at the nucleotide and amino acid levels, respectively. Except for glutamine, amino acid profile analysis revealed that all 81 Ugandan isolates shared the primary 19 amino acids based on the RYMV coat protein region examined. Except for one isolate (UG68) from eastern Uganda that clustered alone, phylogeny analysis revealed two major clades. The Ugandan RYMV isolates were phylogenetically related to those from the Democratic Republic of Congo, Madagascar, and Malawi but not to RYMV isolates in West Africa. Thus, the RYMV isolates in this study are related to serotype 4, a strain common in eastern and southern Africa. RYMV serotype 4 originated in Tanzania, where evolutionary forces of mutation have resulted in the emergence and spread of new variants. Furthermore, mutations are evident within the coat protein gene of the Ugandan isolates, which may be attributed to changing RYMV pathosystems as a result of rice production intensification in Uganda. Overall, the diversity of RYMV was limited and most noticeably in eastern Uganda.

Impact of growth conditions on the nitrogen, protein, colour and amino acid profiles of the cultured macroalga, Palmaria palmata

The impact of growth conditions on the nitrogen, protein, colour and amino acid profiles of Palmaria palmata (from 2 locations) were investigated. Laboratory cultures of P. palmata were grown over a period of 18 days with and without nutrient addition, i.e., with culture medium (F/2) and urea (0.05 or 0.10 g L−1). The total nitrogen (TN) content of cultured P. palmata originating from longlines harvested from Cork increased with the addition of culture medium (F/2) and urea (0.05 g L−1) in comparison to the initial sample (4.15 ± 0.05 vs 1.73 ± 0.03%) while biomass from Galway increased with addition of culture medium (F/2) and urea (0.10 g L−1) in comparison to the initial sample (3.72 ± 0.05 vs 2.43 ± 0.06%). The protein nitrogen (PN) and non-protein nitrogen (NPN) of cultured P. palmata originating from Galway also increased when grown with the addition of nutrients. Nutrient enrichment during growth influenced the colour characteristics (lightness L*, redness a*, yellowness b* and colour difference ΔE) and the electrophoretic protein profile. Correlations between TN and ΔE (r = 0.945) for Cork originated sample, PN and ΔE (r =-0.944) and NPN and ΔE (r = 0.734) for Galway originated sample were observed. In-gel digestion followed by UPLC-MS/MS demonstrated that RuBiSCo, phycoerythrin and allophycocyanin expression in P. palmata was enhanced with nutrient addition. Amino acid profile and score analysis showed variation as a function of nutrient addition. Overall, nutrient inclusion in the growth medium provides a strategy for the enhanced production of high-quality protein by P. palmata.

Amino acids profile of 56 species of microalgae reveals that free amino acids allow to distinguish between phylogenetic groups

Microalgae represent a phototrophic resource with a high protein content, whose nutritional value is very high as a result of its amino acid profile. Although the total amino acid profile has been repeatedly described to change little among phylogenetic groups of microalgae, some variability has occasionally been reported. Part of this uncertainty is associated with the low phylogenetic diversity encompassed in the work to date and the high methodological variability between studies. Among these studies, very few have differentiated between total and free amino acid content for common microalgae samples. Thus, in the present work, the profile of total and free amino acids has been determined in a diverse group composed of 56 species of microalgae belonging to 7 phyla. A multivariate analysis of the total amino acid profile in the studied microalgae group revealed close amino acid patterns throughout microalgae phylogeny and agreed with results obtained from similar analysis performed with published data. Conversely, the free amino acid profile strongly differentiated between phylogenetic groups. On the one hand, species of Cyanobacteria, Plantae, Cryptophyta, and Bacillariophyta showed close free amino acid patterns, characterized by the highest abundance of free glutamic acid. Ochrophyta species were particularly rich in free proline, while the free amino acid profile of Miozoa and Haptophyta species stood out from the rest of the phylogenetic groups for their outstanding levels of the two essential amino acids phenylalanine and lysine. Haptophyta species were also characterized by their much higher free tyrosine content.