Tryptophan Concentrations Research Articles

Influence of Growth Regulators and Tryptophan on Enhancing Production Bioactive Compounds in Callus Cultures of Pistacia weinmannifolia

The experiment was conducted in Tissue culture laboratory at the Biology Department, College of Science ‘University of Al-Qadisiyah. With two explants (the growing apex and the lateral buds), the researchers looked at how the growth regulators (IAA and BA) and Tryptophan affected callus weight and stimulated the synthesis of active substance in Pistacia weinmannifolia plants grown in a tissue culture setting. After sterilization in 70% ethanol solution for 1 minute and 10% sodium hypochlorite (NaOCl) solution for 20 minutes, one node 0.5–1.0 cm in length is planted in test tubes containing MS medium for tissue culture, to which various concentrations of growth regulators and Tryptophan are added, and the tubes are placed in a growth chamber with a temperature of 252 °C and light conditions. Data taken after 45 days of cultivation for all experiments. Better treatment IAA (0.2 mg/L) BA (0.5m.1) and Tryptophan ( 0.1mg/L) gave the highest weight. And significant increase of pentadecanc, Methylox and Catolin. As for treatment IAA ( 0.2mg/L) BA (0.25mg/L) Tryptophan ( 0.1 mg/L) gave highes percentage of active compound Hexadecene.

Interplay between diet, circulating indolepropionate concentrations and cardiometabolic health in US populations

ObjectivesTo identify indolepropionate (IPA)-predicting gut microbiota species, investigate potential diet–microbiota interactions, and examine the prospective associations of circulating IPA concentrations with type 2 diabetes (T2D) and coronary heart disease (CHD)...

Microfluidic chip-based microbial metabolism-indexed BOD sensor for rapid determination of biochemical oxygen demand

Reliance on five-day biochemical oxygen demand (BOD5) as an indicator of water quality has inhibited the development of efficient process control due to the associated uncertainty and lag time. In the work, we proposed a novel strategy for rapid on-site BOD5 determination by a microfluidic chip-based microbial metabolism-indexed BOD sensor (MCB-MMI BOD sensor). The rapid on-site BOD5 detection was achieved by quantifying the equilibrium concentration of tryptophan involved in aerobic biodegradation for alternating the traditional 5-day monitoring of dissolved oxygen variation. The regulated metabolized tryptophan was identified by fluorescence spectrum and converted into BOD5 value. The prominent performance for MCB-MMI BOD sensor BOD5 determination was accessible in the field application, such as decreasing detection time from 5 days to 10 min, lowering sample volume from 250 mL to 2.5 mL, diminishing the working area, extending the detection range (without dilution) from 6 mg/L to 27 mg/L, featured with 83% accuracy, and free-labor automation, which exhibited the infinite potential for MCB-MMI BOD sensor on rapid on-site BOD5 monitoring. We believe the MCB-MMI BOD sensor would broaden its practical applications in BOD5-contained multiple-parameters water quality sensing, and would favorably supply a new tool for sewage-treatment process control, environmental monitoring, and aquaculture.

A systematic review and meta-analysis of the kynurenine pathway of tryptophan metabolism in rheumatic diseases.

https://www.crd.york.ac.uk/prospero, identifier CRD CRD42023443718.

Optical Determination of Tryptophan Using Persistent Luminescence Nanoparticles (PLNPs)

Tryptophan is an essential amino acid that is an important part of the human diet. In this work, label-free photoluminescence sensing based upon persistent luminescent nanoparticles (PLNPs) Zn0.8Ga2O4: Cr3+ is reported to determine tryptophan. Following 254 nm excitation, the PLNPs released luminescence after storing the absorbed light. Compared to the standard fluorescence, the persistent afterglow of the PLNPs was used for detection and imaging without external illumination, thereby eliminating autofluorescence and scattered light generated by biological substrates. For tryptophan concentrations from 4 to 240 µM, a linear relationship was described by F/F 0 = 0.9416 − 0.0024 [Trp] with a correlation coefficient of 0.9911 and a detection limit of 0.19 µM. The recoveries of analyzed samples were between 97.9 and 101.9% providing good accuracy and simple methodology.

Longitudinal associations of macronutrient and micronutrient intake with plasma kynurenines in colorectal cancer survivors up to 12 months posttreatment

BackgroundThe tryptophan-kynurenine pathway is increasingly recognized to play a role in health-related quality of life (HRQoL) after cancer. Because tryptophan is an essential amino acid, and vitamins and minerals act as enzymatic cofactors in the tryptophan-kynurenine pathway, a link between diet and kynurenines is plausible. ObjectivesThis study aimed to investigate the longitudinal associations of macronutrient and micronutrient intake with metabolites of the kynurenine pathway in colorectal cancer (CRC) survivors up to 12 mo posttreatment. MethodsIn a prospective cohort of stage I–III CRC survivors (n = 247), repeated measurements were performed at 6 wk, 6 mo, and 12 mo posttreatment. Macronutrient and micronutrient intake was measured by 7-d dietary records. Plasma concentrations of tryptophan and kynurenines were analyzed using liquid chromatography tandem mass spectrometry (LC/MS-MS). Longitudinal associations were analyzed using linear mixed models adjusted for sociodemographic, clinical, and lifestyle factors. ResultsAfter adjustment for multiple testing, higher total protein intake was positively associated with kynurenic acid (KA) (β as standard deviation [SD] change in KA concentration per 1 SD increase in total protein intake: 0.12; 95% CI: 0.04, 0.20), xanthurenic acid (XA) (standardized β: 0.22; 95% CI: 0.11, 0.33), 3-hydroxyanthranilic acid (HAA) (standardized β: 0.15; 95% CI: 0.04, 0.27) concentrations, and the kynurenic acid-to-quinolinic acid ratio (KA/QA) (standardized β: 0.12; 95% CI: 0.02,0.22). In contrast, higher total carbohydrate intake was associated with lower XA concentrations (standardized β: −0.18; 95% CI: −0.30, −0.07), a lower KA/QA (standardized β: −0.23; 95% CI: −0.34, −0.13), and a higher kynurenine-to-tryptophan ratio (KTR) (standardized β: 0.20; 95% CI: 0.10, 0.30). Higher fiber intake was associated with a higher KA/QA (standardized β: 0.11; 95% CI: 0.02, 0.21) and a lower KTR (standardized β: −0.12; 95% CI: −0.20, −0.03). Higher total fat intake was also associated with higher tryptophan (Trp) concentrations (standardized β: 0.18; 95% CI: 0.06, 0.30) and a lower KTR (standardized β: −0.13; 95% CI: −0.22, −0.03). For micronutrients, positive associations were observed for zinc with XA (standardized β: 0.13; 95% CI: 0.04, 0.21) and 3-hydroxykynurenine (HK) (standardized β: 0.12; 95% CI: 0.03, 0.20) concentrations and for magnesium with KA/QA (standardized β: 0.24; 95% CI: 0.13, 0.36). ConclusionsOur findings show that intake of several macronutrients and micronutrients is associated with some metabolites of the kynurenine pathway in CRC survivors up to 12 mo posttreatment. These results may be relevant for enhancing HRQoL after cancer through potential diet-induced changes in kynurenines. Further studies are necessary to confirm our findings.

Determination of tryptophan and its indole metabolites in follicular fluid of women with diminished ovarian reserve

Tryptophan (TRP) and its indole metabolites exhibit numerous biological effects, especially their antioxidant properties. This study used untargeted metabolomics in conjunction with targeted metabolomics to investigate the differential expression of tryptophan and its indole metabolites in follicular fluid (FF) of diminished ovarian reserve (DOR) and normal ovarian reserve (NOR) populations. This study included patients with DOR (n = 50) and females with NOR (n = 35) who received in vitro fertilization and embryo transfer. Untargeted metabolomics suggests that diminished ovarian reserve affects the metabolic profile of FF, TRP and indole metabolites were significantly down-regulated in the DOR group. Targeted metabolomics quantification revealed that the levels of TRP, IPA and IAA in the FF of the DOR group were significantly lower than those of the NOR group (P < 0.01). The concentration of TRP in FF is positively correlated with the available embryo rate in NOR females. These results provide data support to explore the pathogenesis of DOR and to look for new biomarkers and ovarian protectors. Additionally, alterations in TRP and its indole metabolites in FF may indirectly reflect the interaction between intestinal flora and the follicular microenvironment.

Tryptophan-based in vivo coloring of polyhydroxybutyrate through co-production with indigo and effect on the properties of polymer

With the continuous growth of the demand for eco-friendly alternatives to petroleum-based plastics, polyhydroxybutyrate (PHB) has emerged as a promising alternative because of its biodegradability. However, certain characteristics, such as its color, rigidity, and brittleness, have limited its range of applications. In this study, we investigated the in vivo coloring of PHB with indigo by combining the biosynthesis operons of PHB and indigo, which involved the use of tryptophan as the substrate for the biosynthesis of indigo. The heterologous and homologous tryptophanase genes converted tryptophan to indole, which was further oxidized to indoxyl by flavin monooxygenase (FMO), followed by spontaneous dimerization to indigo in the presence of oxygen. Different indigo-PHB films were obtained by controlling the concentration of tryptophan. Additionally, we investigated the mechanical properties of the indigo-PHB films using UTM analysis and found that their mechanical properties varied according to the amount of indigo incorporated into PHB. Notably, elongation at break in indigo-PHB film, which was produced using 10 mM of tryptophan resulting in a 1.1 mg indigo/g PHB content, significantly improved to 70 % compared to the 7.2 % observed in normal PHB films. Furthermore, indigo-PHB films were subjected to FE-SEM, GPC, and DSC analyses to identify differences, and it was observed that there was a decrease in Tc and Tg values, more obvious in Tg value, in indigo PHB film with 1.1 mg indigo/g PHB content. Considering many approaches to improving PHB properties, our study showed the possibility of different changes in color and improved flexibility via the co-production of indigo and PHB.

Plasma Tryptophan-Kynurenine Pathway Metabolites and Risk for Progression to End-Stage Kidney Disease in Patients With Type 2 Diabetes.

We sought to study the associations between plasma metabolites in the tryptophan-kynurenine pathway and the risk of progression to end-stage kidney disease (ESKD) in patients with type 2 diabetes. Plasma tryptophan, kynurenine, 3-hydroxykynurenine, kynurenic acid, and xanthurenic acid concentrations were measured in discovery (n = 1,915) and replication (n = 346) cohorts. External validation was performed in Chronic Renal Insufficiency Cohort (CRIC) participants with diabetes (n = 1,312). The primary outcome was a composite of incident ESKD (progression to estimated glomerular filtration rate [eGFR] <15 mL/min/1.73 m2, sustained dialysis, or renal death). The secondary outcome was annual eGFR decline. In the discovery cohort, tryptophan was inversely associated with risk for ESKD, and kynurenine-to-tryptophan ratio (KTR) was positively associated with risk for ESKD after adjustment for clinical risk factors, including baseline eGFR and albuminuria (adjusted hazard ratios [HRs] 0.62 [95% CI 0.51, 0.75] and 1.48 [1.20, 1.84] per 1 SD). High levels of kynurenic acid and xanthurenic acid were associated with low risks of ESKD (0.74 [0.60, 0.91] and 0.74 [0.60, 0.91]). Consistently, high levels of tryptophan, kynurenic acid, and xanthurenic acid were independently associated with a slower eGFR decline, while a high KTR was predictive of a faster eGFR decline. Similar outcomes were obtained in the replication cohort. Furthermore, the inverse association between kynurenic acid and risk of ESKD was externally validated in CRIC participants with diabetes (adjusted HR 0.78 [0.65, 0.93]). Accelerated catabolism of tryptophan in the kynurenine pathway may be involved in progressive loss of kidney function. However, shunting the kynurenine pathway toward the kynurenic acid branch may potentially slow renal progression.

Response of date palm Phoenix dactylifera L. Hillawi cultivar to some amino acids

This study was conducted at one of the orchards in the Abi Al-Khasib region of Basrah Governorate during the 2022 growing season to determine the extent of the response of the date palm Hillawi cultivar to spray with amino acids (Glycine, Arginine, and Tryptophan) concentrations of 1000, 1500, and 2000 mg. L-1 per acid, to determine the effect of these acids on some vegetative and fruitful growth characteristics. Showed results of the study showed significant superiority of s amino acid glycine at a concentration of 2000 mg. L-1 in leaf length, leaf width, number of new leaves, chlorophyll, carbohydrates, length and weight of fruit, weight of fleshy part of the fruit weight bunch and reducing sugars. (4.627m, 5.477cm, 17.67, 12.240 mg.100g-1, 49.37 mg.g-1, 3.870cm, 6.057g, 4.817g, 6.823kg, 50.76%) respectively compared with control. Arginine concentration 2000 mg. L-1 significantly in total protein of leaves, and total sugar and soluble solids of fruits. (4.933 mg.g-1, 60.90%, 70.42%) respectively. A tryptophan concentration of 2000 mg. L-1 was significant to fruit size (6.590 cm3). A tryptophan concentration of 1000 mg l was significant to sucrose on fruits (11.260%). Amino acid supplements have a significant impact on plant development and production. Combining different amino acids yields better quality and quantity of fruit. Keywords: Amino acids, vegetative characteristics, fruit characteristics, chemical characteristics, bunch weight.

Organic cation transporter 2 contributes to SSRI antidepressant efficacy by controlling tryptophan availability in the brain

Selective serotonin reuptake inhibitors (SSRI) are common first-line treatments for major depression. However, a significant number of depressed patients do not respond adequately to these pharmacological treatments. In the present preclinical study, we demonstrate that organic cation transporter 2 (OCT2), an atypical monoamine transporter, contributes to the effects of SSRI by regulating the routing of the essential amino acid tryptophan to the brain. Contrarily to wild-type mice, OCT2-invalidated mice failed to respond to prolonged fluoxetine treatment in a chronic depression model induced by corticosterone exposure recapitulating core symptoms of depression, i.e., anhedonia, social withdrawal, anxiety, and memory impairment. After corticosterone and fluoxetine treatment, the levels of tryptophan and its metabolites serotonin and kynurenine were decreased in the brain of OCT2 mutant mice compared to wild-type mice and reciprocally tryptophan and kynurenine levels were increased in mutants’ plasma. OCT2 was detected by immunofluorescence in several structures at the blood-cerebrospinal fluid (CSF) or brain-CSF interface. Tryptophan supplementation during fluoxetine treatment increased brain concentrations of tryptophan and, more discreetly, of 5-HT in wild-type and OCT2 mutant mice. Importantly, tryptophan supplementation improved the sensitivity to fluoxetine treatment of OCT2 mutant mice, impacting chiefly anhedonia and short-term memory. Western blot analysis showed that glycogen synthase kinase-3β (GSK3β) and mammalian/mechanistic target of rapamycin (mTOR) intracellular signaling was impaired in OCT2 mutant mice brain after corticosterone and fluoxetine treatment and, conversely, tryptophan supplementation recruited selectively the mTOR protein complex 2. This study provides the first evidence of the physiological relevance of OCT2-mediated tryptophan transport, and its biological consequences on serotonin homeostasis in the brain and SSRI efficacy.

Growth, Cannibalism, and 5-TH Metabolism in Pufferfish (Takifugu obscurus ♀ × Takifugu rubripes): The Role of Graded Levels of Dietary Tryptophan.

The objective of this study was to investigate the potential effect of graded levels of tryptophan on the growth, cannibalism, and 5-hydroxytryptpamine (5-TH) metabolism in pufferfish (Takifugu obscurus ♀ × Takifugu rubripes ♂). A 63-day feeding trial was performed wherein pufferfish were fed four diets. Three experimental diets were formulated with various levels of tryptophan based on the control diet. Four diets were named as T1, T2, T3, and T4, corresponding to 4.30, 7.80, 14.90, and 23.70 g kg-1 tryptophan of dry diet. Final body weight, weight gain, and specific growth rate were similar between the T1 and T4 groups, but exhibited a significantly increased trend compared to the T2 group. Although survival rate was not affected by various levels of dietary tryptophan, intraspecific cannibalism was significantly reduced in the group fed with highest level of tryptophan (T4). For free amino acid in brain, the concentration of tryptophan was the highest in the T3 group and the lowest in the T2 group, while phenylalanine, tyrosine, and methionine showed an opposite trend between those two groups. The levels of dietary tryptophan not only affected the expression of aromatic amino acid transporter TAT1, but also affected the expression of B0AT1, B0AT2, and 4F2hc in intestine, as well as B0AT1, y+LAT1, and LAT2 in brain. The activity of tryptophan hydroxylase (TPH) in serum increased with the increase of dietary tryptophan, and the expression of TPH1 in brain upregulated in the excessive tryptophan groups (T2, T3, and T4). MAO activity in serum as well as its gene expression in brain and intestine showed a decreased trend in the T4 group. In conclusion, excessive tryptophan (23.70 g kg-1 of dry diet, corresponding to 50.3 g kg-1 of dietary protein) in feed could mitigate cannibalistic behavior of pufferfish and promote the growth, and the reason for this effect might affect the metabolism of 5-TH in vivo.

Metabolic profile of blood serum in experimental arterial hypertension.

The etiology of essential hypertension is intricate, since it employs simultaneously various body systems related to the regulation of blood pressure in one way or another: the sympathetic nervous system, renin-angiotensin-aldosterone and hypothalamic-pituitary-adrenal systems, renal and endothelial mechanisms. The pathogenesis of hypertension is influenced by a variety of both genetic and environmental factors, which determines the heterogeneity of the disease in human population. Hence, there is a need to perform research on experimental models - inbred animal strains, one of them being ISIAH rat strain, which is designed to simulate inherited stress-induced arterial hypertension as close as possible to primary (or essential) hypertension in humans. To determine specific markers of diseases, various omics technologies are applied, including metabolomics, which makes it possible to evaluate the content of low-molecular compounds - amino acids, lipids, carbohydrates, nucleic acids fragments - in biological samples available for clinical analysis (blood and urine). We analyzed the metabolic profile of the blood serum of male ISIAH rats with a genetic stress-dependent form of arterial hypertension in comparison with the normotensive WAG rats. Using the method of nuclear magnetic resonance spectroscopy (NMR spectroscopy), 56 metabolites in blood serum samples were identified, 18 of which were shown to have significant interstrain differences in serum concentrations. Statistical analysis of the data obtained showed that the hypertensive status of ISIAH rats is characterized by increased concentrations of leucine, isoleucine, valine, myo-inositol, isobutyrate, glutamate, glutamine, ornithine and creatine phosphate, and reduced concentrations of 2-hydroxyisobutyrate, betaine, tyrosine and tryptophan. Such a ratio of the metabolite concentrations is associated with changes in the regulation of glucose metabolism (metabolic markers - leucine, isoleucine, valine, myo-inositol), of nitric oxide synthesis (ornithine) and catecholamine pathway (tyrosine), and with inflammatory processes (metabolic markers - betaine, tryptophan), all of these changes being typical for hypertensive status. Thus, metabolic profiling of the stress-dependent form of arterial hypertension seems to be an important result for a personalized approach to the prevention and treatment of hypertensive disease.

Treatment of ankylosing spondylitis with TNFα inhibitors does not affect serum levels of tryptophan metabolites.

The imbalance between the kynurenine and serotonin pathways can have serious consequences, e.g., depression. One of the factors leading to the imbalance between the pathways of tryptophan metabolism is inflammation. The aim of our study was to assess the impact of treatment with tumor necrosis factor-alpha (TNFα)-inhibitors on tryptophan metabolism in patients with ankylosing spondylitis (AS). Forty patients with AS (twenty-eight males, twelve females; mean age 40 ± 11years), qualified to receive anti-TNF-α treatment, were prospectively assessed. As a control group, 20 healthy volunteers (7 males and 13 females, mean age 38 ± 5years) were recruited from the general population. Patients underwent full clinical and biochemical assessment before and after 6months of therapy. Disease activity was assessed by the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI). The presence of depressive disorders was assessed with Beck's Depression Inventory (BDI) scale. Serum concentrations of tryptophan, serotonin, kynurenine, and quinolinic acid were measured. The predominance of the kynurenine pathway in AS patients (compared to the control group) was demonstrated (p < 0.001). Surprisingly, no significant changes in serum levels of tryptophan and its metabolites in AS patients after treatment were found, despite clinical improvement. Moreover, the components of tryptophan metabolism did not correlate significantly with the clinical activity of AS, depression nor laboratory inflammatory markers. Probably some other factors influence the pathways of tryptophan metabolism in patients with ankylosing spondylitis.

Chemical composition of barley and co-products from barley, corn, and wheat produced in South-East Asia or Australia.

A study was conducted to determine the chemical composition of barley and co-products from barley, corn, and wheat produced in South-East Asia or Australia, and to test the hypothesis that production area or production methods can impact the chemical composition of wheat co-products. Samples included seven barley grains, two malt barley rootlets, one corn gluten feed, one corn gluten meal, one corn bran, eight wheat brans, one wheat mill mix, and four wheat pollards. All samples were analyzed for dry matter, gross energy, nitrogen, amino acids (AA), acid hydrolyzed ether extract, ash, minerals, starch, and insoluble dietary fiber and soluble dietary fiber. Malt barley rootlets and wheat co-products were also analyzed for sugars. Chemical composition of barley, malt barley rootlets, and corn co-products were in general similar across countries. Wheat pollard had greater (p<0.05) concentrations of tryptophan, magnesium, and potassium compared with wheat bran, whereas wheat bran had greater (p<0.05) concentration of copper than wheat pollard. There were no differences in chemical composition between wheat bran produced in Australia and wheat bran produced in Thailand. Intact barley contains more starch, but fewer AA, than grain co-products. There were only few differences in the composition of wheat bran and wheat pollard, indicating that the two ingredients are similar, but with different names. However, corn gluten meal contains more protein and less fiber than corn bran.

Improvement of flesh quality, muscle growth and protein deposition in adult grass carp (Ctenopharyngodon idella): The role of tryptophan

The muscle is the main edible part of the animal trunk. Previous studies have shown that tryptophan is the limiting amino acid for protein synthesis. This study investigated whether dietary tryptophan could improve growth performance, flesh quality, muscle growth, and protein deposition in adult grass carp (Ctenopharyngodon idella). 450 grass carp (671.31 ± 1.66 g) were fed with six diets (iso‑nitrogenous) with different concentrations of tryptophan (0.25, 1.66, 3.12, 4.69, 5.95, and 7.61 g/kg diet) for 9 weeks. The results revealed that the optimal tryptophan levels (3.12 or 4.69 g/kg diet) increased feed intake (FI), feed efficiency (FE), percent weight gain (PWG), and specific growth rate (SGR) compared with the deficient group (0.25 g/kg diet), indicating that tryptophan improved the growth performance of adult grass carp. The optimal tryptophan levels increased the muscle contents of protein, lipid, protein-bound amino acids, free amino acids (FAA), pH24h, and shear force; improved the fatty acid (FA) profile in muscle; and reduced cooking loss and lactate content, suggesting that tryptophan improved the flesh quality of adult grass carp. The optimal tryptophan levels increased the myofiber diameter, frequency of >50 μm diameter fiber, mRNA levels of MRFs (MyoD, MyoG, Mrf4, and Myf5), and decreased the mRNA levels of MSTN in muscle, indicating that tryptophan promoted muscle growth in adult grass carp. We further found that the promotion of muscle protein deposition by dietary tryptophan may be related to protein synthesis, ubiquitin-proteasome, and autophagic lysosomal pathways. We discovered that dietary tryptophan increased the mRNA abundances of IGF-1, PI3K, AKT, TOR, and S6K1 and decreased the mRNA abundances of 4EBP1, FOXO1a, FOXO3a, MAFBX, MuRF1, UB, ULK1, Beclin1, ATG5, ATG12, p62, LC3–1, and LC3–2, thereby promoting muscle protein deposition in adult grass carp. The above results showed that dietary tryptophan enhanced growth performance, flesh quality, muscle growth, and muscle protein deposition in adult grass carp. Moreover, using broken line regression, the tryptophan requirement of adult grass carp was estimated to be 3.02 g/kg diet (11.64 g/kg protein) based on PWG.

Assessing the RP-LC-MS-Based Metabolic Profile of Hass Avocados Marketed in Europe from Different Geographical Origins (Peru, Chile, and Spain) over the Whole Season.

Spain dominates avocado production in Europe, with the Hass variety being the most prominent. Despite this, Spanish production satisfies less than 10% of the overall avocado demand in Europe. Consequently, the European avocado market heavily relies on imports from overseas, primarily sourced from Peru and Chile. Herein, a comprehensive characterization of the metabolic profile of Hass avocado fruits from Spain, Peru, and Chile, available in the European market throughout the year, was carried out. The determination of relevant substances was performed using high- and low-resolution RP-LC-MS. Remarkable quantitative differences regarding phenolic compounds, amino acids, and nucleosides were observed. Principal component analysis revealed a natural clustering of avocados according to geographical origin. Moreover, a specific metabolic pattern was established for each avocado-producing country using supervised partial least squares discriminant analysis. Spanish fruits exhibited high levels of coumaric acid malonyl-hexose II, coumaric acid hexose II, and ferulic acid hexose II, together with considerably low levels of pantothenic acid and uridine. Chilean avocado fruits presented high concentrations of abscisic acid, uridine, ferulic acid, succinic acid, and tryptophan. Fruits from Peru showed high concentrations of dihydroxybenzoic acid hexose, alongside very low levels of p-coumaric acid, ferulic acid, coumaric acid malonyl-hexose I, and ferulic acid hexose II.

Amino Acid Profile of the Oil Seed of Guizotia scabra Harvested From Plateau and Kaduna States – Nigeria

Guizotia scabra (L.F cass. composite) is an oil seed crop found wildly and in some areas cultivated at middle and higher elevations in Nigeria and other African countries. The medicinal importance attached to the plant and the acceptance of the seed in some of our rural areas for preparing different types of delicacies is the driving force of this research. The objectives of this study were to determine the amino acids profile. PTH Amino acid analyser was used to determine amino acids in the sample. Amino acid profile revealed that Glutamic acid in the sample from Plateau was 2.57 g/100g protein while Kaduna state was 3.14g/100g protein; arginine in the sample from Plateau was 1.72 g/100g protein while that from Kaduna was 2.06 g/100g protein. Leucine from Plateau was 1.69 g/100g protein while that of Kaduna was 2.10 g/100g protein; aspartic acid in the sample from Plateau was 1.55 g/100g protein while that of Kaduna was 1.80 g/100g protein. The sample from Plateau was 1.00-glycine per100 g protein while that of Kaduna was 1.17 g/100g protein, tyrosine in sample from Plateau was 0.52 g/100g protein while that of Kaduna was 0.34 g/100g protein, isoleucine in sample from Plateau was 0.49 g/100 g protein while that of Kaduna was 0.82 g/100g protein. In addition, Alanine in the sample from Plateau was 0.42 g/100 g protein while that of Kaduna was 0.53 g/100g protein as valine in the sample from Plateau was 0.41 g/100 g protein while that of Kaduna was 0.61 g/100g protein. The sample from Plateau has 0.41g proline per 100g protein while that of Kaduna was 0.51 g/100g protein. Glycine in the sample from Plateau was 0.38 g/100g protein while that of Kaduna was 0.50 g/100g protein, and phenylalanine in the sample from Plateau was 0.35 g/100g protein while that of Kaduna was 0.44 g/100g protein. The sample from Plateau has 0.24g cysteine per100g protein while that of Kaduna was 0.24 g/100g protein; threonine in the sample from Plateau was 0.19 g/100g protein while that of Kaduna was 0.28 g/100g protein. The sample from Plateau has 0.16g serine per g/100g protein while that of Kaduna was 0.22 g/100g protein. The concentration of tryptophan in the sample from Plateau was 0.16 g/100g protein while that of Kaduna was 0.23 g/100g protein and histidine in the sample from Plateau was 0.10 g/100g protein while that from Kaduna was 0.19 g/100g protein. The essential and non-essential amino acids from plateau state are 36.19% and 38.18% respectively while that from Kaduna state are 38.44% and 61.56% respectively. These therefore makes the seed a good source of protein and it is hereby recommended for the fortification of diets that are low in protein for both man and animals.

Liver tryptophan 2,3-dioxygenase: a determinant of anxiety-like behaviour - studies with chronic nicotine administration in rats.

Deletion of the tryptophan 2,3-dioxygenase ( TDO2 ) gene induces an anxiolytic-like behaviour in mice and TDO inhibition by allopurinol elicits an antidepressant-like effect in rats exposed to restraint stress. Chronic nicotine administration inhibits TDO activity, enhances brain serotonin synthesis and exerts anxiolytic- and antidepressant-like effects in rodent models. There is a strong association between anxiety, depression and tobacco use, which is stronger in women than in men. The present study aimed to examine the relationship between behavioural measures of anxiety and depression with liver TDO activity, brain tryptophan concentration and serotonin synthesis in rats treated chronically with nicotine. Behavioural measures included the elevated plus maze (EPM), open field (OFT) and forced swim (FST) tests. Biochemical measures included TDO activity, serum corticosterone and brain Trp, 5-HT and 5-HIAA concentrations. Anxiolytic-like and antidepressant-like effects of chronic nicotine were confirmed in association with TDO inhibition and elevation of brain Trp and 5-HT. Sex differences in behaviour were independent of the biochemical changes. At baseline, female rats performed better than males in OFT and FST. Nicotine was less anxiolytic in females in the open arm test. Nicotine treatment did not elicit different responses between sexes in the FST. Our findings support the notion that liver TDO activity exhibits a strong association with behavioural measures of anxiety and depression in experimental models, but provide little evidence for sex differences in behavioural response to nicotine. The TDO-anxiety link may be underpinned by kynurenine metabolites as well as serotonin.

Polarity-regulated derivatization-assisted LC-MS method for amino-containing metabolites profiling in gastric cancer

Amino-containing compounds, including amino acids, aliphatic amines, aromatic amines, small peptides and catecholamines, are involved in various biological processes and play vital roles in multiple metabolic pathways. Previous studies indicated that some amino-containing metabolites are significant diagnostic and prognostic biomarkers of gastric cancer. However, the discovery of precise biomarkers for the preoperative diagnosis of gastric cancer is still in an urgent need. Herein, we established a polarity-regulated derivatization method coupled with liquid chromatography-mass spectrometry (LC-MS) for amino-containing metabolites profiling in the serum samples of patients with gastric cancer and healthy controls, based on our newly designed and synthesized derivatization reagent (S)-3-(1-(diisopropoxyphosphoryl) pyrrolidine-2-carboxamido)-N-hydroxysuccinimidyl ester (3-DP-NHS). Enhanced separation efficiency and detection sensitivity for amino-containing metabolites were achieved after derivatization. This method exhibited good linearity, recovery, intra- and inter-day precision and accuracy. Only 5 μL serum is needed for untargeted analysis, enabling 202 amino-containing metabolites to be detected. Statistical analysis revealed altered amino acid metabolisms in patients with gastric cancer. Furthermore, ultra high performance liquid chromatography coupled with mass spectrometry (UHPLC-MS/MS) analysis quantification revealed increased serum levels of tryptamine and decreased concentrations of arginine and tryptophan in patients with gastric cancer. Receiver operating characteristic (ROC) curves indicated that an increased tryptamine/tryptophan ratio could serve as a potential biomarker for gastric cancer diagnosis. This study demostrated the possibility of using serum amino acid biomarkers for gastric cancer diagnosis, providing new avenues for the treatment of gastric cancer.