Free Amino Acid Profiles Research Articles

Comparison of two azobenzene-based amino acid derivatization reagents for LC-MS/MS analysis in positive and negative ESI modes

Derivatization reagents based on azobenzene containing different N-hydroxysuccinimidyl moieties– AzoB (carbamate) and AzoC (ester) – are proposed for the LC-ESI-MS analysis of free amino acids in fermented beverages and juices. A dual comparison between LC-MS/MS in positive and negative ESI modes in dynamic Multiple Reaction Monitoring (dMRM) and Neutral Loss Scan was investigated. The results indicate that the studied carbamate derivatization reagent, AzoB, can be employed for targeted analysis (MS/MS) but also for non-targeted analysis of derivatized amino acids thanks to its constant neutral loss (223 Da) that is the same in both ionisation modes. For amines, precursor ion scan can be used as identification tool. The derivatization properties of AzoB and AzoC were compared against other derivatization reagents, and they showed advantages such as fast derivatization reaction and good reactivity with secondary amines. AzoC also displayed a disadvantage –side products were formed that affect the quantitation. Free amino acids profile of Kvass (a fermented beverage from eastern Europe) was determined for first time, proline was found to be the most abundant amino acid.

O79 The effect of early neonatal glutamine supplementation on tissue and digesta free amino acid profiles in suckling low birth weight piglets

O79 The effect of early neonatal glutamine supplementation on tissue and digesta free amino acid profiles in suckling low birth weight piglets

Effect of different packaging methods on the free amino acid profiles of the deep-water rose shrimp (Parapenaeus longirostris) during frozen storage.

The composition of free amino acids (FAAs) in seafood products contributes to characterizing their flavor, as well as freshness and quality during storage. Deep-water rose shrimps (Parapenaues longirostris, Lucas, 1846) (DWRS) are being increasingly harvested in the Mediterranean Sea, and the captured specimens are quickly frozen onboard fishing trawlers to preserve freshness and post-harvest quality. Here, we quantified the FAA profiles of DWRS packaged using five methods: (1) 100% N2; (2) vacuum; (3) 50% N2 + 50% CO2; (4) commercial anhydrous sodium sulfite; and (5) air (control). All samples were quickly frozen at −35°C and stored for 12 months at −18°C. Arginine (661 mg/100 g), proline (538 mg/100 g), and glycine (424 mg/100 g) were the most abundant FAAs, whereas the least abundant were tyrosine (67 mg/100 g), histidine (58 mg/100 g), and aspartic acid (34 mg/100 g). FAAs in all samples gradually (and significantly) increased in the first 6 to 8 months of storage, and then significantly decreased. The sodium sulfite treatment (Method 4) kept the initial FAA contents lower than the other treatments, due to the strong antioxidant action of sulfite agents. Interestingly, similar results were obtained for vacuum packaging (Method 2). Thus, combining frozen storage with vacuum packaging represents an alternative approach to chemical additives in shrimp/prawn processing to meet the increasing demand for high-quality seafood products with long shelf-life.

Determination of Free Amino Acids in Milk, Colostrum and Plasma of Swine via Liquid Chromatography with Fluorescence and UV Detection.

Amino acids are ubiquitous components of mammalian milk and greatly contribute to its nutritional value. The compositional analysis of free amino acids is poorly reported in the literature even though their determination in the biological fluids of livestock animals is necessary to establish possible nutritional interventions. In the present study, the free amino acid profiles in mature swine milk, colostrum and plasma were assessed using a targeted metabolomics approach. In particular, 20 amino acids were identified and quantified via two alternative and complementary reversed-phase HPLC methods, involving two stationary phases based on core-shell technology, i.e., Kinetex C18 and Kinetex F5, and two detection systems, i.e., a diode array detector (DAD) and a fluorescence detector (FLD). The sample preparation involved a de-proteinization step, followed by pre-chromatographic derivatization with 9-fluorenylmethylchloroformate (FMOC-Cl). The two optimized methods were validated for specificity, linearity, sensitivity, matrix effect, accuracy and precision and the analytical performances were compared. The analytical methods proved to be suitable for free amino acid profiling in different matrices with high sensitivity and specificity. The correlations among amino acid levels in different biological fluids can be useful for the evaluation of physio-pathological status and to monitor the effects of therapeutic or nutritional interventions in humans and animals.

Guanidine acetic acid supplementation altered plasma and tissue free amino acid profiles in finishing pigs

BackgroundAs a nutritive feed additive, guanidine acetic acid (GAA) participates in the metabolism of energy and proteins. This study aimed to investigate the effects of GAA on growth performance, organ index, plasma and tissue free amino acid profiles, and related metabolites in finishing pigs. A total of 72 crossbred pigs (body weight 86.59 ± 1.16 kg) were randomly assigned to 1 of 4 dietary treatments (GAA0, GAA500, GAA1000, and GAA1500). They were fed the basal diets supplemented with 0, 500, 1000, or 1500 mg/kg GAA for 42 days, respectively. The growth performance and organ weight were evaluated, and the contents of crude protein, free amino acids, and metabolites in plasma and tissues were determined. Spearman correlation between plasma and tissue free amino acids and related metabolites was also analyzed.ResultsGrowth performance in pigs was not altered by GAA (P > 0.05). The absolute and relative weight of kidneys increased (quadratic, P < 0.05). As dietary GAA concentration was increased, the contents of plasma glycine, serine, leucine, ornithine, and ratio of ornithine/arginine decreased (linear or quadratic, P < 0.05), but the contents of plasma isoleucine and taurine and the ratios of alanine/branched-chain amino acids and proline/ornithine increased quadratically (P < 0.05). The hepatic γ-amino-n-butyric acid content increased linearly and quadratically (P < 0.001), while the carnosine content decreased (quadratic, P = 0.004). The contents of renal arginine, proline, cystine, glutamate, and total amino acids (TAA) decreased quadratically (P < 0.05), but the contents of glycine (quadratic, P = 0.015) and γ-amino-n-butyric acid (linear, P = 0.008) increased. The pancreatic tryptophan content (quadratic, P = 0.024) increased, while the contents of pancreatic proline (linear, P = 0.005) and hydroxyproline (quadratic, P = 0.032) decreased in response to GAA supplementation. The contents of cardiac essential amino acids (EAA), nonessential amino acids (NEAA), and TAA in GAA1000 were higher than those in GAA1500 (P < 0.05). Supplementing with GAA linearly increased the contents of methionine, threonine, valine, isoleucine, leucine, phenylalanine, tryptophan, lysine, histidine, arginine, serine, alanine, glutamine, asparagine, tyrosine, proline, taurine, cystathionine, α-aminoadipic acid, β-aminoisobutyric acid, EAA, NEAA, and TAA in the spleen (P < 0.05). A strong Spearman correlation existed between plasma and tissue free amino acids and related metabolites.ConclusionGAA supplementation did not altered pig growth performance, but it altered plasma and tissue free amino acid profiles and the contents of related metabolites in pigs in a tissue-dependent manner.

Sautéing and roasting effect on free amino acid profiles in portobello and shiitake mushrooms, and the effect of mushroom- and cooking-related volatile aroma compounds on meaty flavor enhancement

Using mushroom to enhance meaty flavor is a common culinary practice; however, nutrition and taste studies associated with amino acid changes during mushroom cooking are limited, and mushroom aroma's enhancement of meaty flavor has not been verified. This study aimed to 1) investigate free amino acid profile changes in raw, sautéed, and roasted portobello and shiitake, and 2) investigate if certain volatiles from mushroom culinary preparation could increase meaty flavor. A total of 23 amino acids, including all 9 essential, were quantified using gas chromatography-mass spectrometry and high-performance liquid chromatography. Both cooking methods caused significant (p ≤ 0.05) free amino acid loss, while mushroom variety significantly impacted most amino acid contents. The following 8 solutions were served to 82 participants: a blank (basic taste ingredients), a control (blank with meaty flavor), and three aroma blocks (control with mushroom-like, roasted, and grilled flavors) at two intensity levels. The control solution showed significantly higher umami taste than the blank. Compared to the control and blank, the grilled aroma significantly increased meaty flavor intensity and acceptance, overall acceptance, and umami taste; while the roasted and mushroom-like aroma blocks did not show meaty flavor enhancement. Meaty flavor was mainly driven by salty, umami, and sweet tastes as well as thickness mouthfeel. This study demonstrates how culinary application impacts free amino acid content in mushroom and how meaty flavor can be enhanced by aroma compounds derived from non-animal sources.

Quantitation of non-derivatized free amino acids for detecting inborn errors of metabolism by incorporating mixed-mode chromatography with tandem mass spectrometry

IntroductionAmino acids are critical biomarkers for many inborn errors of metabolism, but amino acid analysis is challenging due to the range of chemical properties inherent in these small molecules. Techniques are available for amino acid analysis, but they can suffer from long run times, laborious derivatization, and/or poor resolution of isobaric compounds. ObjectiveTo develop and validate a method for the quantitation of a non-derivatized free amino acid profile in both plasma and urine samples using mixed-mode chromatography and tandem mass spectrometry. MethodsChromatographic conditions were optimized to separate leucine, isoleucine, and allo-isoleucine and maintain analytical runtime at less than 15 min. Sample preparation included a quick protein precipitation followed by LC-MS/MS analysis. Matrix effects, interferences, linearity, carryover, acceptable dilution limits, precision, accuracy, and stability were evaluated in both plasma and urine specimen types. ResultsA total of 38 amino acids and related compounds were successfully quantitated with this method. In addition, argininosuccinic acid was qualitatively analyzed. A full clinical validation was performed that included method comparison to a reference laboratory for plasma and urine with Deming regression slopes ranging from 0.38 to 1.26. ConclusionThis method represents an alternative to derivatization-based methods, especially in urine samples where interference from metabolites and medications is prevalent.

Amino acid balance of microbial-tissue complex in the small intestinal and liver under administration of lead acetate

It is known that the initiating event of liver damage during lead intoxication is the effect of lead on the intestinal microbiome and the metabolic profile of enterocytes. The aim of the study was to reveal the dependence of the concentrations of free amino acids and their derivatives in the liver on the amino acid pool of the microbial-tissue complex of the small intestine. We used rats weighing 120‒140 g, which were injected intragastrically for three weeks with drinking water with lead acetate. Free amino acids and their nitrogen-containing metabolites in the microbial-tissue complex of the intestine and liver were determined by HPLC. Enteral intake of lead acetate with drinking water changes the profile of free amino acids and their derivatives in the microbial-tissue complex of the small intestine, which correlates with a violation of amino acid homeostasis in the liver. The analysis of the correlations of the indicators we determined indicates the essential role of nitrogen-containing metabolites of amino acids ‒ ethanolamine and phosphoethanolamine, taurine, and cystathionine. The direction of the correlation relationship between various nitrogen-containing metabolites of the microbial-tissue complex and the liver can be considered as marker of discoordination of homeostasis.

Determination of Free Amino Acids in Bee Pollen by Liquid Chromatography with Fluorescence Detection

Bee pollen is one of the hive products that is of most interest today due to its multiple beneficial health properties, making it an increasingly popular food supplement. Bee pollen contains many bioactive compounds, such as fatty acids, vitamins, minerals, proteins, and amino acids, among others. In the present study, the free amino acid content was determined in bee pollen by using liquid chromatography coupled to a fluorescence detector. Sample treatment consisted of a solvent extraction of the free amino acids with ultrapure water and a further centrifugation of the extract, which was repeated twice. After that, it was necessary to perform a pre-column derivatization of the amino acids using a combination of two reagents (o-phthalaldehyde and 9-fluorenylmethyl chloroformate) prior to their separation in a Gemini® C18 reverse phase column in gradient elution mode. The analytical performance was evaluated, and several commercial bee pollen samples were analyzed. Significant differences in the free amino acid profile and concentration, which ranged between 19 and 192 mg/g, were observed depending on the botanical origin of the samples.

Effect of pH on Rhodomonas salina growth, biochemical composition, and taste, produced in semi-large scale under sunlight conditions

Rhodomonas salina is a microalgal species, belonging to the cryptophytes, and is widely used as aquaculture feed because of its high nutritional profile and phycoerythrin content. This study investigated the effect of pH on the growth, biochemical composition, and taste of R. salina when cultivated on a semi-large scale under natural light conditions. Two tubular photobioreactors (200 L) were used for the cultivation of R. salina with sunlight as the only illumination source. Two different pH setpoints were applied, 7 and 8.5. Optimal temperature and nutrient conditions were applied, according to previous research findings. The results demonstrated that the productivity of R. salina was higher at pH 7, 0.06–0.14 gdry weight L−1 day−1, compared to pH 8.5, 0.03–0.12 gdry weight L−1 day−1. It was found that protein and total fatty acid concentrations were higher in the biomass that was produced at pH 8.5, 33.7% and 12.3% of dry weight, respectively, while at pH 7, the protein content was 31.9% and the total fatty acids 8.8% of dry weight. The phycoerythrin concentration, like protein, was higher at pH 8.5, 2.7% of dry weight, compared to pH 7, 1% of dry weight. The free amino acid and nucleotide profile of R. salina was affected by the pH, resulting in increased equivalent umami concentration at pH 7. For the sensory evaluation, an expert panel on algae flavors evaluated the effect of pH on the taste of R. salina, reporting that the biomass that was produced at pH 7 had more umami flavor than the biomass that was produced at pH 8.5, which was evaluated as more bitter.

Effects of Dietary Chlorogenic Acid Supplementation Derived from Lonicera macranthoides Hand-Mazz on Growth Performance, Free Amino Acid Profile, and Muscle Protein Synthesis in a Finishing Pig Model.

Chlorogenic acid (CGA), as one of the richest polyphenol compounds in nature, has broad applications in many fields due to its various biological properties. However, initial data on the effects of dietary CGA on protein synthesis and related basal metabolic activity has rarely been reported. The current study is aimed at (1) determining whether dietary CGA supplementation improves the growth performance and carcass traits, (2) assessing whether dietary CGA alters the free amino acid profile, and (3) verifying whether dietary CGA promotes muscle protein synthesis in finishing pigs. Thirty-two (Large × White × Landrace) finishing barrows with an average initial body weight of 71.89 ± 0.92 kg were randomly allotted to 4 groups and fed diets supplemented with 0, 0.02%, 0.04%, and 0.08% CGA, respectively. The results indicated that, compared with the control group, dietary supplementation with 0.04% CGA slightly stimulated the growth performance of pigs, whereas no significant correlation was noted between the dietary CGA levels and animal growth (P > 0.05). Furthermore, the carcass traits of pigs were improved by 0.04% dietary CGA (P < 0.01). In addition, dietary CGA significantly improved the serum free amino acid profiles of pigs (P < 0.01), while 0.04% dietary CGA promoted more amino acids to translocate to skeletal muscles (P < 0.05). The relative mRNA expression levels of SNAT2 in both longissimus dorsi (LD) and biceps femoris (BF) muscles were augmented in the 0.02% and 0.04% groups (P < 0.05), and the LAT1 mRNA expression in the BF muscle was elevated in the 0.02% group (P < 0.05). We also found that dietary CGA supplementation at the levels of 0.04% or 0.08% promoted the expression of p-Akt and activated the mTOR-S6K1-4EBP1 axis in the LD muscle (P < 0.05). Besides, the MAFbx mRNA abundance in the 0.02% and 0.04% groups was significantly lower (P < 0.05). Our results revealed that dietary supplementation with CGA of 0.04% improved the free amino acid profile and enhanced muscle protein biosynthesis in the LD muscle in finishing pigs.

Utilising waste from soybean processing as raw materials for the production of preparations with antioxidant properties, serving as natural food preservatives - A pilot study

Technologies for the production of protein hydrolysates from soybean bran, left over from the soy flour production process, have been designed. The influence of using various enzyme preparations on antioxidant activity and quality (zeta potential, free amino acid profile, sodium dodecyl sulfate polyacrylamide gel electrophoresis, total phenolic content) of soybean bran hydrolysates were assessed. It was found that regardless of the applied enzyme, the obtained hydrolysates were characterised by high antioxidant properties measured via the FRAP method and metal chelating activity (13.51–15.58 μM Trolox/mg and 93.5–95.15%), while the ability to scavenge free radicals, varies depending on the method of obtaining the hydrolysate. Hydrolysates acquired as a result of digestion with Alcalase were characterized by the highest content of protein and polyphenols, as well as high antioxidant properties. Therefore, they were used in further research as additives to minced meat. It has been stated that the protein hydrolysate produced from soybean bran, despite increasing the hardness of meat model products, cannot be used as an antioxidant agent, because it does not reduce lipid oxidation in meat. Careful analysis of its chemical structure and interactions with meat constituents is necessary to detect the exact cause of the pro-oxidative effect observed.

Development of a Novel Nutrition-Related Multivariate Biomarker for Mild Cognitive Impairment Based on the Plasma Free Amino Acid Profile.

Nutritional epidemiology has shown the importance of protein intake for maintaining brain function in the elderly population. Mild cognitive impairment (MCI) may be associated with malnutrition, especially protein intake. We explored blood-based biomarkers linking protein nutritional status with MCI in a multicenter study. In total, 219 individuals with MCI (79.5 ± 5.7 year) from 10 institutions and 220 individuals who were cognitively normal (CN, 76.3 ± 6.6 year) in four different cities in Japan were recruited. They were divided into the training (120 MCI and 120 CN) and validation (99 MCI and 100 CN) groups. A model involving concentrations of PFAAs and albumin to discriminate MCI from CN individuals was constructed by multivariate logistic regression analysis in the training dataset, and the performance was evaluated in the validation dataset. The concentrations of some essential amino acids and albumin were significantly lower in MCI group than CN group. An index incorporating albumin and PFAA discriminated MCI from CN participants with the AUC of 0.705 (95% CI: 0.632–0.778), and the sensitivities at specificities of 90% and 60% were 25.3% and 76.8%, respectively. No significant association with BMI or APOE status was observed. This cross-sectional study suggests that the biomarker changes in MCI group may be associated with protein nutrition.

Complete Replacement of Fishmeal With Plant Protein Ingredients in Gibel Carp (Carassius auratus gibelio) Diets by Supplementation With Essential Amino Acids Without Negative Impact on Growth Performance and Muscle Growth-Related Biomarkers

This study was conducted to investigate the effects of substitution of dietary fishmeal (FM) by compound plant protein supplemented with essential amino acids on growth performance, plasma physiology, and muscle growth-related genes of gibel carp (Carassius auratus gibelio). Four diets with equal digestible protein were prepared, where 30FM (control feed) contained 30% FM and land animal protein as a protein source, 10FM contained 10% FM, PMAa contained full plant meal (PM) supplemented with crystalline amino acid, and PM contained full PM feed. There was no significant difference in the specific growth rate (SGR) with 30FM, 10FM, and PMAa diets (p &amp;gt; 0.05); however, the SGR of PM group was the lowest with significant difference (p &amp;lt; 0.05). Feed efficiency of the PM group was the lowest with significant difference (p &amp;lt; 0.05). The whole-body crude protein content of fish in PMAa group was significantly higher than that in each group with additional FM (p &amp;lt; 0.05). There were no significant differences in plasma total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) or low-density lipoprotein cholesterol (LDL-C), and free amino acid profile of 30FM, 10FM, and PMAa groups (p &amp;gt; 0.05); however, they were significantly higher than that in PM group (p &amp;lt; 0.05). The expression of key genes in the TOR signaling pathway (tor, s6k1, 4e-bp2, and eif4e), autophagy (ulk1 and atg13), and ubiquitin–proteasome (trim63 and znrf2) system of the PMAa group was similar to that of the FM group (p &amp;gt; 0.05), indicating that the muscle growth-related biomarker genes were positively regulated by the appropriate dietary amino acid composition at the transcriptional level. These results suggest that FM in gibel carp diet can be totally replaced by PM without negative impact on growth performance and muscle growth-related biomarkers at the transcriptional level, which provided the requirement of digestible protein and balanced amino acid profile is satisfied.

Changes in the free amino acid profile of pickling cucumber during lactic acid fermentation.

Free amino acid (FAA) profiles of fresh, acidified, naturally fermented, and starter culture fermented cucumbers were analyzed by liquid chromatography triple quadrupole mass spectrometry. Fermented cucumbers contained more total FAA than acidified cucumbers (1,302 ± 102mg/kg and 635 ± 35mg/kg, respectively). Total FAA content of fermented cucumber was similar regardless of brine salt levels (2-6% NaCl) and starter culture addition. Glutamine (1491.4± 69.3mg/kg), γ-aminobutyric acid (GABA, 269.6± 21.4mg/kg), asparagine (113.0± 6.4mg/kg), and citrulline (110.3±8.5mg/kg) were the most abundant FAA in fresh pickling cucumber, whereas GABA (181.3±21.5mg/kg), isoleucine (165.2± 11.2mg/kg), leucine (129.8± 10.9mg/kg), and lysine (110.9± 5.0mg/kg) were the most abundant in fermented cucumber. GABA and ornithine were produced during fermentation, indicating glutamate decarboxylase and arginine deiminase activities. Notably, ornithine was significantly higher in natural (63.3±31.5mg/kg) versus starter culture fermented cucumbers (3.0±0.7mg/kg). This new information on FAA composition of fresh and fermented pickling cucumbers shows the impact of fermentation conditions on cucumber amino acid profiles while providing insight for manipulating fermentations for health promotion and consumer acceptance. PRACTICAL APPLICATION: This study reports changes in the free amino acid profiles of raw, fermented and acidified cucumbers, which may be valuable for understanding the impact of these foods on human health and nutrition. This information is useful for food microbiologists studying the metabolism of lactic acid bacteria during fermentation and/or designing starter cultures and could contribute to the development of novel fermented cucumber pickle products with enhanced nutritional value.

The use of metabolomics tools in the evaluation of the fattening performance of lambs

This study aimed to determine the metabolomic characteristics associated with the fattening performance of the Awassi lamb breed under intensive fattening for 90 days. Twenty-four lambs were used in the research. The lambs were divided into two groups according to their fattening performance (good fattening performance, n = 12, and poor fattening performance, n = 12), and their metabolomic properties were evaluated. The differences between the two research groups in the amino acids of alloisoleucine, aspartic acid, histidine, hydroxylysine, isoleucine, lysine, methionine, phenylalanine, tryptophan, valine, and 1-methylhistidine were found to be statistically significant (P ≤ 0.001). Moderately significant negative correlations were found between daily concentrate feed intake and 3-methylhistidine (r = −0.469; P = 0.021), hydroxylysine (r = −0.408; P = 0.048), and serotonin (r= −0.467; P = 0.021); as well as between the average daily weight gain (ADWG) and alloisoleucine (r = −0.528; P = 0.008), 3-methylhistidine (r = −0.440; P = 0.032), and hydroxylysine (r = −0.577; P = 0.003). A moderate positive correlation was found between hydroxyisovalerylcarnitine and ADWG (r = 0.476; P = 0.019), and a negative correlation was found between hydroxyisovalerylcarnitine and the feed conversion ratio (r = −0.430; P = 0.036). Pathway analysis revealed that the most important biological pathway was the phenylalanine, tyrosine, and tryptophan biosynthesis pathway. The results of the research reveal the potential for plasma free amino acid and carnitine profiles to be used as candidate biomarkers in the evaluation of fattening performance in lambs.

Metabolic Effects of Cedar Tar on Colon Cancer Cell Line (HCT-116): A Follow-up Study

Objective: Colon cancer (CC) is considered to be the most common cancers seen worldwide. Surgery and chemotherapy are the leading methods used in treatment. In recent years, the therapeutic properties of natural products have been investigated and used in drug development. Cedrus libani plant that normally grows in Syria and Turkey, some studies have shown that the plant’s extract (cedar tar) has anti-microbial and anti-cancer properties on colon cancer. Recently, metabolic changes have been identified as the hallmark of cancer, and various metabolic drugs are being investigated in clinical trials. This study was carried out to investigate the effects of cedar tar on the amino acid metabolism of colon cancer cells. Materials and Methods: Colon cancer cells (HCT-116) were homogenized in cold PBS medium after incubation with 30 µg/mL dose of cedar tar for 24 hours in appropriate medium. The intracellular free amino acid profile in the samples was analyzed by LC-MS/MS method. Statistical analysis of the obtained data was done with SPSS and MetaboAnalyst 5.0 program. Results: According to the statistical analysis results, significant positive correlations were found between β-alanine, anserine amino acids and apoptotic effects of cedar tar between the untreated control and cedar tar-treated groups, while a negative correlation was found with O-Phosphorylethanolamine amino acid. Conclusion: By increasing the levels of β-alanine and anserine amino acids in colon cancer cells, cedar tar reduces both the metastatic character of the cells and inhibits tumor formation; It caused cell proliferation and energy deprivation by reducing the level of O-Phosphorylethanolamine amino acid, which is defined as a pro-tumorigenic metabolite. Cedar tar both triggered apoptosis and changed amino acid metabolism in colon cancer cells. It has been determined that cedar tar has the potential to be used as a natural product in the treatment of colon cancer.

Effects of Cereal Malts Used as Improver on Physico-Chemical, Nutritional and Sensory Characteristics of Wheat and Millet Composites Breads

The aim of this study was to optimize composite breads of wheat and whole millet flour by the use of natural improvers. Three types of local malted cereals were used as natural improvers. The millet flour was fermented with EPSs producing LAB strain prior to use. The technological characteristics of the composite flours were determined using an alveograph. The physico-chemical and nutritional characteristics of the composite breads were determined using standard methods and their sensory profiles were evaluated by a panel of 35 consumers. The alveograph results showed an increase in dough resistance, deformation and a decrease in extensibility and elasticity with the level of incorporation of millet flour. From the results of physico-chemical analyses of composite breads, no significant difference (p > 0.05) was observed in the use of the three types of local cereal malts except for the incorporation of 50% of the millet flour. The control sample presented the lowest acidity and dry matter value, the highest water content and pH value. No significant difference (p > 0.05) was observed in the use of the three types of cereal malts for the macronutrient contents of the composite bread samples. However, differences were observed according to the levels of incorporation. Macronutrients results showed an increase in protein content (11.17% ± 0.28% - 14.01% ± 0.10%/DM); crude fat content (1.86% ± 0.05% - 2.48% ± 0.20%/DM) and a decrease in carbohydrates content (85.36% ± 0.54% - 81.06% ± 0.36%/ DM). Regarding the content of mineral elements, significant differences (p < 0.05) were observed in the use of the three types of cereal malts for the incorporation of 15% (Mg and Fe content), 30% (Fe, Zn and K) and 50% (content of Zn, K, Na and Mg) of millet flour. The free amino acid profile revealed three essential amino acids such as valine, isoleucine and lysine. Breads incorporated with 30% of whole millet flour were the most appreciated by consumers.

Free amino acids profile and quality properties of Turkish pastırma cured with potassium lactate and sodium chloride combinations

The effects of different potassium lactate (PL) and NaCl combinations on free amino acid profile and quality properties of Turkish pastırma were determined in this study. The PL used in pastırma manufacturing had significant effects on lysine, isoleucine, leucine, phenylalanine, threonine, tryptophan, aspartic acid, glutamic acid, serine, glycine, proline (p < .01), histidine, methionine, alanine, cystine (p < .05), moisture, TBARS, pH, residual nitrite, salt, a*, b* (p < .01), L* (p < .05), TAMB, LAB, M/S, and Y-M counts (p < .01). TBARS, residual nitrite, and a* values of pastırma samples produced with PL were lower than those of control pastırma (Tc). The differences among pastırma groups were not significant (p > .05) in sensory scores. However, brittleness, palatability, salinity, and overall acceptability scores of Tc pastırma samples were generally higher than that of PL groups. When all results were evaluated together, it was concluded that it would be appropriate to use 0.5% or 1.0% PL instead of NaCl for pastırma. Novelty impact statement The aim of this study was to determine the concentration of appropriate substitution by reducing the high NaCl amount in pastırma to protect consumer health. The high levels of potassium lactate did not adversely affect the sensory properties of pastırma. The lowest amount of essential and non-essential amino acids were determined in the control group.

Chemically acidified, live and heat-inactivated fermented dairy yoghurt show distinct bioactive peptides, free amino acids and small compounds profiles

Previous studies found variations in the health-promoting effects of consuming different dairy products. This study aims at investigating the chemical composition of microbial fermented yogurt, chemically acidified yogurt and whole milk to understand the differences in the effects these products exert on human health. For this purpose, peptides and small compounds present in the products were examined using a combination of liquid chromatography mass spectrometry and nuclear magnetic resonance spectroscopic techniques. Results revealed that each product had its own characteristic peptide, free amino acid and small compound profile, and database search for bioactivity disclosed that fermented yogurt manufactured using a starter culture is associated with a higher bioactivity potential than chemically acidified yogurt or whole milk. Additional cold storage (14 days) further enhances the bioactivity potential of fermented yogurt while heat-inactivation, ensuring long shelf-life, modulates the proteins available for proteolysis and thereby the peptide profile generated.