High-performance Liquid Chromatography System Research Articles

Design and Prototype of an Automated Column-Switching HPLC System for Radiometabolite Analysis

Column-switching high performance liquid chromatography (HPLC) is extensively used for the critical analysis of radiolabeled ligands and their metabolites in plasma. However, the lack of streamlined apparatus and consequently varying protocols remain as a challenge among positron emission tomography laboratories. We report here the prototype apparatus and implementation of a fully automated and simplified column-switching procedure to allow for the easy and automated determination of radioligands and their metabolites in up to 5 mL of plasma. The system has been used with conventional UV and coincidence radiation detectors, as well as with a single quadrupole mass spectrometer.

DEUTERIUM FRACTIONATION DURING AMINO ACID FORMATION BY PHOTOLYSIS OF INTERSTELLAR ICE ANALOGS CONTAINING DEUTERATED METHANOL

ABSTRACT Deuterium (D) atoms in interstellar deuterated methanol might be distributed into complex organic molecules through molecular evolution by photochemical reactions in interstellar grains. In this study, we use a state-of-the-art high-resolution mass spectrometer coupled with a high-performance liquid chromatography system to quantitatively analyze amino acids and their deuterated isotopologues formed by the photolysis of interstellar ice analogs containing singly deuterated methanol CH2DOH at 10 K. Five amino acids (glycine, α-alanine, β-alanine, sarcosine, and serine) and their deuterated isotopologues whose D atoms are bound to carbon atoms are detected in organic residues formed by photolysis followed by warming up to room temperature. The abundances of singly deuterated amino acids are in the range of 0.3–1.1 relative to each nondeuterated counterpart, and the relative abundances of doubly and triply deuterated species decrease with an increasing number of D atoms in a molecule. The abundances of amino acids increase by a factor of more than five upon the hydrolysis of the organic residues, leading to decreases in the relative abundances of deuterated species for α-alanine and β-alanine. On the other hand, the relative abundances of the deuterated isotopologues of the other three amino acids did not decrease upon hydrolysis, indicating different formation mechanisms of these two groups upon hydrolysis. The present study facilitates both qualitative and quantitative evaluations of D fractionation during molecular evolution in the interstellar medium.

Simultaneous quantitative analysis of Ni, VO, Cu, Zn and Mn geoporphyrins by liquid chromatography-high resolution multistage mass spectrometry: Method development and validation

A method is described for the identification and quantification of Cu, Ni, VO, Zn and Mn metalloporphyrins in geological samples using a high performance liquid chromatography (HPLC) system coupled to a high resolution Thermo Orbitrap XL mass spectrometer (MS). The linear correlation of the detector response to the compound concentrations in Cu, Ni, VO, Zn and Mn porphyrin standards (R2 values between 0.9975 and 0.9994), verified the suitability of the methodology for the quantification of these compounds. Furthermore, the method was validated by the analysis of complex porphyrin distributions in geological sample isolates from the Australian Toolebuc Formation and Bight Basin. By using the high resolution of the Orbitrap MS detector it was not only possible to reproduce the porphyrin distributions reported from previous analyses of the same isolates, but also to identify and resolve a range of additional compounds such as an iso-butyl C34 VO porphyrin indicative of palaeoenvironmental photic zone euxinia and several Cu and Zn porphyrins. The methodology described here provides a new high resolution tool for routine analysis of complex metalloporphyrin distributions in geological sample extracts, enabling the simultaneous quantitative analysis of Cu, Ni, VO, Zn and Mn porphyrins without the need of prior de-metalation or further fractionation of the porphyrin extract. The high resolution of the Orbitrap MS combined with the ability to perform multistage mass spectrometry leads to a significant improvement in compound detection and identification, which shows a high potential in the analysis of low abundance porphyrins, such as high-molecular-weight porphyrins with extended alkyl side-chains.

New on-line separation workflow of microbial metabolites via hyphenation of analytical and preparative comprehensive two-dimensional liquid chromatography.

Microbial metabolites represent an important source of bioactive natural products, but always exhibit diverse of chemical structures or complicated chemical composition with low active ingredients content. Traditional separation methods rely mainly on off-line combination of open-column chromatography and preparative high performance liquid chromatography (HPLC). However, the multi-step and prolonged separation procedure might lead to exposure to oxygen and structural transformation of metabolites. In the present work, a new two-dimensional separation workflow for fast isolation and analysis of microbial metabolites from Chaetomium globosum SNSHI-5, a cytotoxic fungus derived from extreme environment. The advantage of this analytical comprehensive two-dimensional liquid chromatography (2D-LC) lies on its ability to analyze the composition of the metabolites, and to optimize the separation conditions for the preparative 2D-LC. Furthermore, gram scale preparative 2D-LC separation of the crude fungus extract could be performed on a medium-pressure liquid chromatograph×preparative high-performance liquid chromatography system, under the optimized condition. Interestingly, 12 cytochalasan derivatives, including two new compounds named cytoglobosin Ab (3) and isochaetoglobosin Db (8), were successfully obtained with high purity in a short period of time. The structures of the isolated metabolites were comprehensively characterized by HR ESI-MS and NMR. To be highlighted, this is the first report on the combination of analytical and preparative 2D-LC for the separation of microbial metabolites. The new workflow exhibited apparent advantages in separation efficiency and sample treatment capacity compared with conventional methods.

Source contributions of Polycyclic Aromatic Hydrocarbons in soils around oilfield in the Brahmaputra Valley

Surface soils from Borholla oilfield in the upper Brahmaputra Valley in India were studied for the USEPA's 16 priority Polycyclic Aromatic Hydrocarbons (PAHs). Analysis of PAHs was carried out by high performance liquid chromatography (HPLC) system equipped with an UV detector. Seasonality in PAHs concentrations was evident and the concentrations were found to be greater in post-monsoon season. There has been a dominance of low molecular weight PAHs (80–90% of total PAHs) indicating recent deposition from combustion sources. The concentration profiles appeared in the decreasing order of 3-ring >2-ring >4-ring >5-ring >6 ring PAHs. The sources of PAHs were identified using isomer pair ratios and Principal Component Analysis-Multiple Linear Regression (PCA-MLR) and Positive Matrix Factorisation (PMF). The ratios of diagnostic pairs indicated for both pyrogenic and petrogenic input of PAHs. The PCA-MLR modelling revealed that the <16% of contribution came from petrogenic origin and the rest 85% was found to be from pyrogenic sources. The PMF model also shown that <19% of PAHs source were petrogenic origin whereas rest from pyrogenic origin. The correlations of black carbon (BC) with PAHs also supported the pyrogenic contribution. The analysis of air mass back trajectories revealed that there has been contribution of both local and distant sources, through long range transport of pollutants, which were deposited to the site.

Liquid MALDI MS Analysis of Complex Peptide and Proteome Samples.

Matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) mass spectrometry (MS) is well-known to be a powerful technique for the analysis of biological samples. By using glycerol-based liquid support matrices (LSMs) instead of conventional MALDI matrices the power of this technique can be extended further. In this study, we exploited LSMs for the identification of complex samples, that is, the Lactobacillus proteome and a bovine serum albumin (BSA) digest. Liquid and solid MALDI samples were manually and robotically prepared by coupling a nanoflow high-performance liquid chromatography (nanoHPLC) system to an automated MALDI sample spotting device. MS and MS/MS data were successfully acquired at the femtomole level using TOF/TOF as well as Q-TOF instrumentation and used for protein identification searching sequence databases. For the BSA digest analysis, liquid MALDI samples resulted in peptide mass fingerprints, which led to a higher confidence in protein identification compared with solid (crystalline) MALDI samples; however, postsource decay (PSD) MS/MS analysis of both the proteome of Lactobacillus plantarum WCFS1 cells and BSA digest showed that further optimization of the formation and detection of peptide fragment ions is still needed for liquid MALDI samples, as the MS/MS ion search score was lower than that for the solid MALDI samples, reflecting the poorer quality of the liquid MALDI-PSD spectra, which can be attributed to the differences in PSD parameters and their optimization that is currently achievable.

Comparative anlysis of the differential expressed proteins in serumbetween healthy and Brucellaovis infected sheep

Disease-related serum proteins in sheep infected with Brucellaovis were assessed by conventional two-dimensional gel electrophoresis (2-DE). High-abundance proteins in serum were depleted by Albumin &amp; IgG Depletion SpintrapTM, with the remaining proteins retrieved using the 2-D clean-up kit. Differentially expressed proteins were detected with the PDQUest8.0 software and identified by a high performance liquid chromatography system equipped with an ion trap mass spectrometer. Both SDS-PAGE and 2-DE gel electrophoresis confirmed that high-abundance protein components were removed thoroughly by the 2-D clean-up kit and Albumin &amp; IgG Depletion SpintrapTM. A total of 9 differentially expressed protein spots were successfully identified as haptoglobin, serum amyloid A, Ig heavy chain, Igl-1 chain, and apolipoprotein C-III, known to be involved in stress response, energy metabolism, and material transport. These findings provide a valuable clue for investigating host immune response to pathogens at the protein level; further understanding of these novel proteins identified would be helpful for finding out potential candidate targets for diagnosis and developing new vaccines for brucellosis.

Enantioselective determination of citrulline and ornithine in the urine of d-amino acid oxidase deficient mice using a two-dimensional high-performance liquid chromatographic system

Two-dimensional high-performance liquid chromatographic (2D-HPLC) and 2D-HPLC-mass spectrometric (2D-HPLC–MS) systems have been designed and developed for the determination of the citrulline (Cit) and ornithine (Orn) enantiomers. Several d-amino acids have already been identified as novel physiologically active molecules and biomarkers, and the enantioselective evaluation of the amounts, distributions and metabolisms of non-proteinogenic amino acids gain as well increasing interest. In the present study, highly selective analytical methods were developed using a capillary monolithic ODS column (0.53mm i.d. x 1000mm) for the reversed-phase separation of the target analytes from the matrix compounds in the first dimension, and a narrowbore-Pirkle type enantioselective column, KSAACSP–105S (1.5mm i.d. x 250mm), was used for the enantiomer separation in the second dimension. The amino acids were analyzed after pre-column derivatization with 4-fluoro-7-nitro-2,1,3-benzoxadiazole (NBD-F) and detected by the fluorescence detector and MS. The systems were applied to the urine of d-amino acid oxidase (DAO) deficient B6DAO− mice and control C57BL mice to evaluate the presence and metabolism of the Cit and Orn enantiomers in mammals. As a result, all of the 4 target enantiomers (d-Cit, l-Cit, d-Orn, l-Orn) were found in the urine of both strains. The %D value of Cit (d-Cit/Cit×100) increased about 3-fold in the urine of the DAO deficient mice and that of Orn also tended to increase with the DAO deficiency. These results were definitely confirmed by a 2D-HPLC–MS detection system. Further investigations about the biological significance of these d-isomers are currently ongoing.

Monitoring gradient profile on-line in micro- and nano-high performance liquid chromatography using conductivity detection

In micro- or nano-flow high performance liquid chromatography (HPLC), flow-splitters and gradient elutions are commonly used for reverse phase HPLC separations. When a flow splitter was used at a high split-ratio (e.g., 1000:1 or higher), the actual gradient may deviate away from the programmed gradient. Sometimes, mobile phase concentrations can deviate by as much as 5%. In this work, we noticed that the conductivity (σ) of a gradient decreased with the increasing organic-solvent fraction (φ). Based on the relationship between σ and φ, a method was developed for monitoring gradient profile on-line to record any deviations in these HPLC systems. The conductivity could be measured by a traditional conductivity detector or a capacitively coupled contactless conductivity detector (C4D). The method was applied for assessing the performance of an electroosmotic pump (EOP) based nano-HPLC. We also observed that σ value of the gradient changed with system pressure; a=0.0175ΔP (R2=0.964), where a is the percentage of the conductivity increase and ΔP is the system pressure in bar. This effect was also investigated.

Isolation, identification, and acetochlor-degrading potential of a novel Rhodococcus sp. MZ-3

ABSTRACTA new species of Rhodococcus, designated strain MZ-3, which could degrade acetochlor efficiently were isolated and identified. The isolate could degrade and utilize acetochlor as the sole source of carbon, nitrogen, and energy for growth. The optimal conditions for the degradation and growth of MZ-3 were pH 7.0 and 30°C. Under these conditions, this strain could completely degrade 200 mg/L of acetochlor within 12 h of incubation. During the biodegradation process, the enantioselectivity of the strain was investigated using a chiral high-performance liquid chromatography (HPLC) system. However, no obvious enantioselectivities were found. 2-chloro-N-(2-methyl-6-ethylphenyl) acetamide (CMEPA) was detected as the intermediate using liquid chromatography-mass spectrometry (LC-MS) analyses. Our results suggest that strain MZ-3 might be a promising microorganism for the bioremediation of acetochlor-contaminated environments because of its acetochlor-degrading performance.

The emission properties of bmimBF4 determined using an HPLC system. Significant influence of emission of impurities

Abstract Determination of the real emission properties of imidazolium room temperature ionic liquids (RTILs) is highly desirable because many of their applications are based on the exact knowledge of their emission properties. Unfortunately, it has not been possible to obtain even two identical emission spectra for any of imidazolium RTILs! In this study an innovative use of a high performance liquid chromatography (HPLC) system coupled with a PDA spectrophotometer and fluorescence detector has been employed. This system allows a separation of impurities from 1-butyl-3-methylimidazolium tetrafluoroborate (bmimBF 4 ), and to a high degree, a separation of bmimBF 4 -related species, which makes it an irreplaceable setup for determining real absorption and emission properties of a compound studied. Thus, it was possible to calculate the emission quantum yield, Φ E −4 (HPLC system) which is by about ten times (!) smaller than Φ E ∼ 10 ‐2 (spectrofluorometer). It was also possible to calculate the contribution of the emission of impurities to the total emission observed, which was as high as ≥70%. This clearly shows that the influence of emission of impurities on the emission spectrum and the Φ E of bmimBF 4 is astoundingly great.

Saliva and Plasma Monohydroxycarbamazepine Concentrations in Pediatric Patients With Epilepsy

Monohydroxycarbamazepine (MHD, 10-hydroxy-carbamazepine) is the main active metabolite of oxcarbazepine (OXC). The present study aims to investigate the relationship between plasma and saliva concentrations of MHD in Chinese children with epilepsy. Plasma and saliva samples were collected and MHD levels were measured by high-performance liquid chromatography system. Linear regression analysis was conducted between the dose of OXC and saliva concentrations, between the dose of OXC and plasma concentrations, and between the saliva concentrations and plasma concentrations. Student's t-test was used for unpaired data. A one-way analysis of variance was used for analyzing co-medication in subgroups of patients. A total of 58 blood samples and 58 saliva samples were obtained from 52 pediatric epileptic patients, with a median age of 5.67 years (0.58-15 years, 23 males and 29 females). There was an apparent positive correlation between the plasma and saliva MHD concentrations [Y = 0.77x - 0.85 (n = 58), R = 0.908, P < 0.01]. MHD plasma and saliva concentrations were positively correlated to daily drug dose (r = 0.461 and 0.417; P < 0.01 respectively). The saliva/plasma MHD ratio was around 0.71 and had no significant difference with age, gender, and combined medications. When data were analyzed for subgroups (one group taking OXC as monotherapy, the second group taking OXC in add-on with non-enzyme-inducing antiepileptic drugs, and the third group taking OXC in add-on with hepatic-enzyme-inducing antiepileptic drugs or moderate inducers), no significant difference was found between plasma and saliva MHD concentrations in all the above 3 groups. High correlation between plasma and saliva MHD levels supported the use of saliva as an alternative to plasma for OXC monitoring in children with epilepsy.

Validated HPLC determination of 4-dimethylaminoantipyrine in different suppository bases.

Suppositories are important tools for individual therapy, especially in paediatrics, and an instrumental assay method has become necessary for the quality control of dosage units. The aim of this work was to develop a rapid, effective high-performance liquid chromatography method to assay aminophenazone in extemporaneous suppositories prepared with two different suppository bases, adeps solidus and massa macrogoli. With a novel sample preparation method developed by the authors, 4-dimethylaminoantipyrine was determined in these suppository bases with 95-105% recovery. The measurements were carried out on a Shimadzu Prominence ultra high-performance liquid chromatography system equipped with a 20 μl sample loop. The separation was achieved on a Hypersil ODS column, with methanol, sodium acetate buffer (pH 5.5±0.05, 0.05 M, 60:40, v/v) as the mobile phase at a flow rate of 1.5 ml/min. The chromatograms were acquired at 253 nm. The chromatographic method was fully validated in accordance with current guidelines. The presented data demonstrate the successful development of a rapid, efficient and robust sample preparation and high-performance liquid chromatography method for the routine quality control of the dosage units of suppositories containing 4-dimethylaminoantipyrine.

Role of pharmacogenetics on deferasirox AUC and efficacy.

We evaluated deferasirox pharmacokinetic according to SNPs in genes involved in its metabolism and elimination. Moreover, we defined a plasma area under the curve cut-off value predicting therapy response. Allelic discrimination was performed by real-time PCR. Drug plasma concentrations were measured by a high performance liquid chromatography system coupled with an ultraviolet method. Pharmacokinetic parameters were significantly influenced by UGT1A1 rs887829C>T, UGT1A3 rs1983023C>T and rs3806596A>G SNPs. Area under the curve cut-off values of 360 μg/ml/h for efficacy were here defined and 250 μg/ml/h for nonresponse was reported. UGT1A3 rs3806596GG and ABCG2 rs13120400CC genotypes were factors able to predict efficacy, whereas UGT1A3 rs3806596GG was a nonresponse predictor. These data show how screening patient's genetic profile may help clinicians to optimize iron chelation therapy with deferasirox.

Comparison and bias estimation of three methods in determination of glycated hemoglobin A1c

To evaluate the bias of three different methods in determination of glycated hemoglobin A1c (HbA1c). According to Clinical and Laboratory Standards Institute (CLSI)EP9-A3 document, 40 serum specimens among linear range were tested by immunoturbidimetry assay (Roche Tina-quant), capillary electrophoresis (Sebia Minicap FP), high performance liquid chromatography system (HPLC, Trinity Biotech Premier Hb 9210™). RESULTS were analyzed by pairwise comparision. The difference plots and scatter plots were analyzed. The results of outliers were examined by extreme studentized deviate (ESD) method. The best regression model was chosen to fit the regression equation and the biases were calculated at the level of medical decision and judged the comparability according to the half of Tea acceptance standard. Scatter plots and ESD results showed good correlation among test results of 40 samples, no abnormal values were found. Based on proportional difference deviation plots, proportional difference rank order deviation plots, numerical deviation plots and ranked order difference plots, weighted least squares (WLS) (Roche(X) vs sebia(Y1)), ordinary linear regression (OLR) (Roche(X) vs Trinity (Y2)) and Deming (Sebia(Y1) vs Trinity(Y2)) were chosen to fit regression analysis model. The regression equations were Y1 =-0.420 3+ 1.052 7X, Y2 =-0.174 0+ 1.027 0X, Y2=0.423 1+ 0.959 0Y1, respectively. Assuming the HbA1c medical decision points of 10%, 16% to regression equation, the proportional biases were 1.06% and 2.61% at Roche(X) and sebia(Y1) system, 0.96% and 1.60% at Roche(X) and Trinity (Y2) system, 0.13% and -1.47% at Sebia(Y1) and Trinity(Y2) system respectively, which were all lower than the acceptable values. The measurement values of HbA1c by capillary electrophoresis (Sebia Minicap FP), HPLC (Trinity Biotech Premier Hb 9210™) and immunoturbidimetry assay (Roche Tina-quant), are comparable.

Bisphenol A (BPA) in thermal paper used for receipts

&#x0D; Background: Bisphenol A (BPA) is a proven endocrine disruptor and has been found in the urine of 95% of Canadians. Though the chemical has been banned for use in certain applications, it is still common in items such as thermal paper used for receipts because the compound is heat stable. This study aims to determine if the levels found in thermal receipt paper are high enough to pose a public health concern. Methods: Samples of thermal paper used for receipts were tested for BP A by soaking and incubating lOOmg of the paper in lOmL of methanol for 3 hours at room temperature, and then overnight at 4°C. The resulting methanol solution was then analyzed by using an HPLC (high performance liquid chromatography) system with fluorescence detection. Results: A total of 30 receipts were tested from various stores around the Lower Mainland, including retail stores and restaurants. Of the 30 samples, 13 tested positive for bisphenol A, and of those 13, the amount ranged from 0.124 to 871.17 mg BPA per kg paper. Using the provisional total daily intake (0.025mg/kg body weight/day) set by Health Canada in 1996, results indicate that there can be enough BPA present in a minimum of 2 grams of the paper to exceed the daily limit for a person weighing 70kg. However, the human body does not absorb all of the BPA it may come into contact with, nor does a person touch the entire surface of the paper; thus, more than 2 grams of thermal paper would be required to actually exceed the pTDI. Conclusion: Although the human body does not absorb all of the BPA it may come into contact with, thermal receipt paper can still be a significant source of BP A, especially for those who handle them frequently, such as cashiers. Public education on common sources of BP A, such as thermal receipts, would reduce exposure.&#x0D;

Quantitative estimation of Donepenzil hydrochloride tablet by HPLC

A simple, rapid, reliable and accurate HPLC method has been developed and validated as per the ICH guidelines for the quantitative determination of Donepezil HCl in bulk and tablets. The water HLC-10, high performance liquid chromatography system were used. The LOQ is detected at concentration 0.05mg/ml and the linearity range is 50-150g/ml. An optimum concentration scanned in the range 200-350 nm and ? max of the drug is 230 nm. No any interference at developed (R t = 8.22 min) and also the ? max peak is sharp. The Accuracy of the method was found to be in the range of 99.70% to 100.26%. The mean Inter and Intraday assay Relative Standard deviation (%RSD) were less than 0.69%. The Proposed method was found to be Linear, precise and accurate for the quantitative estimation of Donepezil in tablet formulations and can be used for commercial purposes.

Influence of carboxylic ion-pairing reagents on retention of peptides in thin-layer chromatography systems with C18 silica-based adsorbents

One of the main problems related to chromatography of peptides concerns adverse interactions of their strong basic groups with free silanol groups of the silica based stationary phase. Influence of type and concentration of ion-pairing regents on peptide retention in reversed-phase high-performance liquid chromatography (RP-HPLC) systems has been discussed before. Here we present influence of these mobile phase additives on retention of some peptide standards in high-performance thin-layer chromatography (HPTLC) systems with C18 silica-based adsorbents. We prove, that due to different characteristic of adsorbents used in both techniques (RP HPLC and HPTLC), influence of ion-pairing reagents on retention of basic and/or amphoteric compounds also may be quite different. C18 silica-based HPTLC adsorbents provide more complex mechanism of retention and should be rather considered as mixed-mode adsorbents.

Impact of plasma transaminase levels on the peripheral blood glutamate levels and memory functions in healthy subjects

Background & aimsBlood aspartate aminotransferase (AST) and alanine transaminase (ALT) levels are the most frequently reliable biomarkers of liver injury. Although AST and ALT play central roles in glutamate production as transaminases, peripheral blood levels of AST and ALT have been regarded only as liver injury biomarkers. Glutamate is a principal excitatory neurotransmitter, which affects memory functions in the brain. In this study, we investigated the impact of blood transaminase levels on blood glutamate concentration and memory. MethodsPsychiatrically, medically, and neurologically healthy subjects (n=514, female/male: 268/246) were enrolled in this study through local advertisements. Plasma amino acids (glutamate, glutamine, glycine, d-serine, and l-serine) were measured using a high performance liquid chromatography system. The five indices, verbal memory, visual memory, general memory, attention/concentration, and delayed recall of the Wechsler Memory Scale-Revised were used to measure memory functions. ResultsBoth plasma AST and ALT had a significant positive correlation with plasma glutamate levels. Plasma AST and ALT levels were significantly negatively correlated with four of five memory functions, and plasma glutamate was significantly negatively correlated with three of five memory functions. Multivariate analyses demonstrated that plasma AST, ALT, and glutamate levels were significantly correlated with memory functions even after adjustment for gender and education. ConclusionsAs far as we know, this is the first report which could demonstrate the impact of blood transaminase levels on blood glutamate concentration and memory functions in human. These findings are important for the interpretation of obesity-induced metabolic syndrome with elevated transaminases and cognitive dysfunction.

Phytochemical Compounds and Antioxidant Capacity of Tucum-Do-Cerrado (Bactris setosa Mart), Brazil's Native Fruit.

This study identified major phenolic compounds of the tucum-do-cerrado (Bactris setosa) peel, as well as antioxidant activity and total phytochemical compound concentration of different extracts of the peel and pulp of this fruit. Phenolic compounds of the different extracts of tucum-do-cerrado peel were identified and quantified using a high-performance liquid chromatography system coupled to a diode array detector (DAD). Total phytochemical compound content was determined by spectrophotometric assays and the antioxidant activity by ferric reducing antioxidant power and β-carotene/linoleic assays. Total phenolic, flavanols, total anthocyanins and yellow flavonoids concentration of tucum-do-cerrado were 122-, 14-, 264- and 61-fold higher in the peel than in the pulp, respectively. The aqueous, methanolic and ethanolic extracts of the tucum-do-cerrado peel exhibited higher antioxidant activity compared to its pulp. Flavanols, anthocyanins, flavones, phenolic acids and stilbenes were the main phenolic classes identified in the tucum-do-cerrado peel extracts. Results suggest that the antioxidant capacity and the phytochemical compound content of the tucum-do-cerrado are mainly associated with the peel. Although flavonoids are the main compounds identified in tucum-do-cerrado peel, other phenolics identified in minor amounts, such as phenolic acids and stilbenes, may be responsible for the high antioxidant capacity of the fruit.