Water-soluble Metabolites Research Articles

Metabolic profiling for water-soluble metabolites in patients with schizophrenia and healthy controls in a Chinese population: A case-control study

Objectives: Objective measures integrated with clinical symptoms may improve early prevention and detection of schizophrenia. Herein we aim to evaluate potential water-soluble metabolic biomarkers in schizophrenia.Methods: We recruited adults with schizophrenia (n = 113) who had not received pharmacological treatment for at least 1 month prior to enrollment and 111 age- and sex-matched healthy subjects from Weifang, Shandong province, China. All serum samples were analysed using liquid chromatography-tandem mass spectrometry coupled with a hydrophilic interaction liquid chromatography column.Results: Eleven metabolites, namely carnitines (oleoylcarnitine, l-palmitoylcarnitine, 9-decenoylcarnitine and 2-trans,4-cis-decadienoylcarnitine), polar lipids (lysophosphatidylcholine (LPC)(P-16:0), LPC (16:0), LPC (15:0) and LPC(14:0)), amino acids (taurine and l-arginine), and organic acid (2,5-dichloro-4-oxohex-2-enedioate), separated the patients and healthy controls. Compared with healthy controls, taurine, l-palmitoylcarnitine and oleoylcarnitine levels were higher, whereas the remaining eight metabolites were lower in patients with schizophrenia. A combination of four metabolites, i.e., oleoylcarnitine, 9-decenoylcarnitine, LPC (15:0) and LPC (14:0), provided the most robust between-group separation.Conclusions: This study appears to distinguish between groups of patients and controls, which should be considered as a contribution to putative potential biomarkers. The water-soluble metabolites were determined to be significantly different between the groups in the current study, and were primarily related to cellular bioenergetics, notably oxidative stress.

Substrate specificity and promiscuity of horizontally transferred UDP-glycosyltransferases in the generalist herbivore Tetranychus urticae

Uridine diphosphate (UDP)-glycosyltransferases (UGTs) catalyze the addition of UDP-sugars to small hydrophobic molecules, turning them into more water-soluble metabolites. While their role in detoxification is well documented for vertebrates, arthropod UGTs have only recently been linked to the detoxification and sequestration of plant toxins and insecticides. The two-spotted spider mite Tetranychus urticae is a generalist herbivore notorious for rapidly developing resistance to insecticides and acaricides. We identified a set of eight UGT genes that were overexpressed in mites upon long-term acclimation or adaptation to a new host plant and/or in mite strains highly resistant to acaricides. Functional expression revealed that they were all catalytically active and that the majority preferred UDP-glucose as activated donor for glycosylation of model substrates. A high-throughput substrate screening of both plant secondary metabolites and pesticides revealed patterns of both substrate specificity and promiscuity. We further selected nine enzyme-substrate combinations for more comprehensive analysis and determined steady-state kinetic parameters. Among others, plant metabolites such as capsaicin and several flavonoids were shown to be glycosylated. The acaricide abamectin was also glycosylated by two UGTs and one of these was also overexpressed in an abamectin resistant strain. Our study corroborates the potential role of T. urticae UGTs in detoxification of both synthetic and natural xenobiotic compounds and paves the way for rapid substrate screening of arthropod UGTs.

Native Nanodiscs and the Convergence of Lipidomics, Metabolomics, Interactomics and Proteomics

The omics disciplines remain largely distinct sciences due to the necessity of separating molecular classes for different assays. For example, water-soluble and lipid bilayer-bound proteins and metabolites are usually studied separately. Nonetheless, it is at the interface between these sciences where biology happens. That is, lipid-interacting proteins typically recognize and transduce signals and regulate the flow of metabolites in the cell. Technologies are emerging to converge the omics. It is now possible to separate intact membrane:protein assemblies (memteins) directly from intact cells or cell membranes. Such complexes mediate complete metabolon, receptor, channel, and transporter functions. The use of poly(styrene-co-maleic acid) (SMA) copolymers has allowed their separation in a single step without any exposure to synthetic detergents or artificial lipids. This is a critical development as these agents typically strip away biological lipids, signals, and metabolites from their physiologically-relevant positions on proteins. The resulting SMA lipid particles (SMALPs) represent native nanodiscs that are suitable for elucidation of structures and interactions that occur in vivo. Compatible tools for resolving the contained memteins include X-ray diffraction (XRD), cryo-electron microscopy (cryoEM), mass spectrometry (MS), and nuclear magnetic resonance (NMR) spectroscopy. Recent progress shows that memteins are more representative than naked membrane proteins devoid of natural lipid and is driving the development of next generation polymers.

Metabolome profiling of various seaweed species discriminates between brown, red, and green algae.

Among seaweed groups, brown algae had characteristically high concentrations of mannitol, and green algae were characterised by fructose. In red algae, metabolite profiles of individual species should be evaluated. Seaweeds are metabolically different from terrestrial plants. However, general metabolite profiles of the three major seaweed groups, the brown, red, and green algae, and the effect of various extraction methods on metabolite profiling results have not been comprehensively explored. In this study, we evaluated the water-soluble metabolites in four brown, five red, and two green algae species collected from two sites in northern Japan, located in the Sea of Japan and the Pacific Ocean. Freeze-dried seaweed samples were processed by methanol-water extraction with or without chloroform and analysed by capillary electrophoresis- and liquid chromatography-mass spectrometry for metabolite characterisation. The metabolite concentration profiles showed distinctive characteristic depends on species and taxonomic groups, whereas the extraction methods did not have a significant effect. Taxonomic differences between the various seaweed metabolite profiles were well defined using only sugar metabolites but no other major compound types. Mannitol was the main sugar metabolites in brown algae, whereas fructose, sucrose, and glucose were found at high concentrations in green algae. In red algae, individual species had some characteristic metabolites, such as sorbitol in Pyropia pseudolinearis and panose in Dasya sessilis. The metabolite profiles generated in this study will be a resource and provide guidance for nutraceutical research studies because the information about metabolites in seaweeds is still very limited compared to that of terrestrial plants.

High-resolution magic angle spinning nuclear magnetic resonance (HR-MAS-NMR) as quick and direct insight of almonds

Almonds are the tasty seeds of Prunus dulcis plants globally appreciated for the pleasant palatability and remarkable nutritional value, therefore it is very spread as snack and as basic ingredient of the confectionery products. The HR-MAS-NMR is a simple spectroscopy able to directly and quickly explore the chemical composition of powdered seed samples dispersed in D2O. 1H spectra witness the remarkable presence of triglyceride fatty esters together with sucrose; other minor water soluble metabolites are also detectable. This very rough approach is effectively providing chemical profiles featuring almond samples. In this analysis we were able to statistically distinguish the “Avola” almonds from other marketed products submitted to the same analysis. This is just a first investigation based on the main compounds but it might pave the way toward the quantitative evaluation of many other compounds in the almond therefore implementing the HR-MAS-NMR knowledge of these precious seeds.

A comparative assessment of water-soluble selenium metabolites in commercial selenised yeast supplements by liquid chromatography-electrospray ionisation QTOF-MS

Liquid chromatography-inductively coupled plasma-mass spectrometry (LC-ICP-MS) was utilised for the screening of organoselenium metabolites in the water extracts of selenised yeast products. Four different commercially available yeast products and a reference Se-enriched yeast standard, (SELM-1) were analysed. Total selenium and selenomethionine concentrations were determined by ICP-MS and LC-ICP-MS, respectively. Ultrafiltration using a 3 kDa molecular weight cut-off membrane was used in the present study for sample clean-up. The water-soluble extracts were lyophilised to increase analyte concentration, resuspended in water and analysed by liquid chromatography-electrospray ionisation quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS). Selenium-containing species were confirmed using selenium’s unique isotopic pattern. This approach allowed for the detection of approximately 129 previously unreported selenium metabolites across the different yeast samples. Determination of the elemental composition of 14 previously unreported selenocompounds was advanced through MS2 analysis and accurate molecular mass determination (Δ ppm<1.6 for all proposed elemental compositions).

Analysis of water soluble metabolites for orbital lymphoproliferative disease using metabolomics

Analysis of water soluble metabolites for orbital lymphoproliferative disease using metabolomics

Protocols for NMR Analysis in Livestock Metabolomics.

Nuclear magnetic resonance (NMR) spectroscopy is widely considered to be one of the most robust and reproducible analytical platforms for conducting metabolomic experiments. As a metabolomic platform, NMR is not particularly sensitive, but it is nondestructive and requires no prior derivatization or chromatographic separation. It is also very automatable, easy to perform, and highly reproducible and can be used to accurately quantify dozens of metabolites in complex mixtures. To perform a successful NMR metabolomic experiment, it is important to follow good practices in sample preparation, data acquisition, and data analysis. In this chapter, we will describe, step-by-step, the preparation of different livestock samples, including both biofluids (whole blood, serum, urine, rumen content, and fecal water) and tissues (liver, muscle, testis). We will also describe the protocols for acquiring optimal NMR spectra and the techniques used to identify and quantify water-soluble metabolites by NMR spectroscopy.

Composition of Mycelia and Basidiomata of the Culinary-Medicinal Golden Oyster Mushroom, Pleurotus citrinopileatus (Agaricomycetes) by Nuclear Magnetic Resonance Spectroscopy.

Nuclear magnetic resonance (NMR) spectroscopy has been used to obtain the profile of soluble metabolites on fungus. To enhance the ergothioneine content in Pleurotus citrinopileatus mycelium, amino acid precursors were used for submerged fermentation. The study aimed to analyze the metabolites of high-ergothioneine and regular P. citrinopileatus mycelia (HEPM and RPM) and P. citrinopileatus basidiomata (PCB) using NMR spectroscopy. Principal component analysis (PCA) was applied to differentiate and to describe the differences among three sets of metabolites. The results showed that 55 water-soluble metabolites of PCB, HEPM, and RPM were identified and classified into five groups including amino acids, carbohydrates, organic acids, purines and pyrimidines, and others. Contents of total soluble metabolites were in descending order as follows: PCB (135 mg/g) > HEPM (58 mg/g) > RPM (44 mg/g). The score plot and loading plot separated using PCA showed that the first two components were responsible for R2X = 97.1% and the variance [R2X(1) = 74% for principal component PC1 and R2X(2) = 23.1% for PC2]. A metabolic pathway map of P. citrinopileatus mycelium was established and the differences in the metabolites of RPM and HEPM with precursors added were illuminated.

Effects of Polychlorinated Pesticides and Their Metabolites on Phospholipid Organization in Model Microbial Membranes.

Polychlorinated pesticides (PPs) were classified as persistent organic pollutants because of their toxicity, limited degradability in the environment, bioaugmentation, and accumulation in animal tissues. PPs accumulate in the environment mainly in the soils and water sediments where they are toxic to the decomposer organisms including soil bacteria and fungi. Therefore, there is an urgent need to search for the microorganisms capable of PP biodegradation which could be applied for soil bioremediation. The exact mechanism of PP microbial toxicity is unknown; however, there is evidence that it can be membrane related. To shed light on the interactions of PPs with microbial membranes, we applied Langmuir monolayers formed by phospholipids as model biomembranes. The model membranes were formed by phospholipids typical to microbial membranes: cardiolipins and phosphatidylglycerols the main components of Gram positive bacteria membranes, phosphatidylcholine typical to fungal membranes, as well as phosphatidylethanolamine found in the inner membranes of Gram negative bacteria. For the studies, the most ecotoxic PPs and their water-soluble metabolites were chosen. The monolayers were studied with the application of mutually complementary techniques: Langmuir technique, grazing incidence X-ray diffraction, and PM-IRRAS spectroscopy. It turned out that the cyclodiene PPs are more membrane active than monocyclic PPs and that the possibility of their incorporation is strictly related to the phospholipid structure. The membranes prepared with cardiolipin turned out to be especially resistant to PP incorporation. Regarding the metabolites, pentachlorophenol turned out to be especially structure breaking, affecting the molecular organization of all of the investigated phospholipids.

Effects of inter-day and intra-day variation on salivary metabolomic profiles

BackgroundSalivary secretion is an important parameter reflecting the health status of an individual and has been used clinically for the diagnosis of various oral diseases, such as xerostomia. Salivary metabolomic profiling is considered an emerging potential tool for the detection of various systemic diseases. To our knowledge, this is the first study to investigate the quantitative relationship between salivary secretion volume and salivary metabolomic profile. MethodsTo evaluate inter- and intra-day variations in salivary secretion, 234 saliva samples were collected three times per day for three days from 13 subjects and analyzed. Capillary electrophoresis-mass spectrometry was used for non-targeted quantification of water-soluble metabolites. ResultsNo significant inter- or intra-day variations were observed in salivary secretion volume. No significant inter-day variations were observed in metabolomic patterns. In contrast, significant intra-day variations were observed in salivary metabolomic profiles. The difference was more obvious for stimulated saliva than for unstimulated saliva. These profile changes were independent of salivary secretion volume. ConclusionsOur results indicated that diurnal change had a greater effect on salivary metabolomic profiles than the other factors. Hence, sampling time should be tightly controlled to minimize unexpected bias in the clinical use of salivary metabolomics.

Chronobiology in nephrology: the influence of circadian rhythms on renal handling of drugs and renal disease treatment

Chronobiology studies the phenomenon of rhythmicity in living organisms. The circadian rhythms are genetically determined and regulated by external synchronizers (the daylight cycle). Several biological processes involved in the pharmacokinetics and pharmacodynamics of drugs are subjected to circadian variations. Chronopharmacology studies how biological rhythms influence pharmacokinetics, pharmacodynamics, and toxicity, and determines whether time-of-day administration modifies the pharmacological characteristics of the drug. Chronotherapy applies chronopharmacological studies to clinical treatments, determining the best biological time for dosing: when the beneficial effects are maximal and the incidence and/or intensity of related side effects and toxicity are minimal. Most water-soluble drugs or drug metabolites are eliminated by urine through the kidney. The rate of drug clearance in the urine depends on several intrinsic variables related to renal function including renal blood flow, glomerular filtration rate, the ability of the kidney to reabsorb or to secrete drugs, urine flow, and urine pH, which influences the degree of urine acidification. Curiously, all these variables present a circadian behavior in different mammalian models. The circadian rhythms have influence in the renal physiology, pathophysiology, and pharmacology, and these data should be taken into account in clinical nephrology practice.

Drying and extraction effects on three edible brown seaweeds for metabolomics

Metabolomics is often used to comprehensively elucidate the metabolites in organisms like seaweed. Amino acids hydrolysed from proteins and certain targeted metabolites in seaweed have been investigated. However, water-soluble metabolites like free amino acids, organic acids, and sugars have seldom been comprehensively analysed. Metabolomics are valuable tools for these studies, but they require optimisation of pre-treatment methodology. Here, we evaluated various pre-treatment drying and extraction methods for brown seaweed metabolomics. Three edible brown seaweeds (Cladosiphon okamuranus [Mozuku], Saccharina japonica [Kombu], and Undaria pinnatifida [Wakame]) were used. Freeze-drying and oven-drying at both 40 and 80 °C were investigated. Methanol-water extracts with and without chloroform were compared. Metabolites were evaluated and quantified using liquid chromatography-mass spectrometry and capillary electrophoresis-mass spectrometry. The results showed that metabolite profiling was determined mainly by seaweed species identity rather than pre-treatment method. Freeze-drying yielded higher metabolite concentrations than oven-drying at either 40 or 80 °C. The effects of extraction with and without chloroform on metabolite concentration varied with seaweed species.

Pre-treatment of extracellular water soluble pigmented secondary metabolites of marine imperfect fungus protects HDF cells from UVB induced oxidative stress.

The present study explores the UVB-induced oxidative stress protective efficacy of the pigmented fungal metabolite (identified as DHICA: 5,6-dihydroxyindole-2-carboxylic acid - a melanin precursor) using human dermal fibroblast (HDF) cells. DHICA is a water soluble pigment of the marine Aspergillus nidulans strain SG 28. Preliminary compatibility studies revealed 95% HDF cell viability with 600 μM concentration of DHICA. HDF cells were exposed to UVB irradiation with and without DHICA pre-treatment and the morphological, physiological and molecular level changes were observed accordingly. The results suggested that UVB exposure increases reactive oxygen species (ROS) generation and subsequent DNA damage in HDF cells, whereas DHICA pre-treatment appreciably reduces ROS generation and DNA damage. DHICA pre-treatment upregulates the antioxidant enzyme expressions and reduces the number of cells in the sub-Go/G1 phase. Gene expression analysis of TNF-α, IL-6, COX-2, NF-κB, Bax and Caspase 3 suggested that pre-treatment with DHICA downregulates the above-mentioned genes and simultaneously upregulates Bcl2 expression. In vivo experiments with BALB/c mice suggested that the topical application of DHICA protected mice skin from UVB-induced oxidative stress (which increases the epidermal thickness as evidenced in the skin sectioning). Thus, DHICA application protects the cells from UVB induced oxidative stress and may find applications in sunscreen cosmetic preparations.

Metabolite characterization of powdered fruits and leaves from Adansonia digitata L. (baobab): A multi-methodological approach

The metabolite profiling of extracts from Adansonia digitata L. (baobab) fruit pulp and leaf, and the quantification of their major components, was conducted by means of reverse-phase, high-performance liquid chromatography with photodiode array detection, coupled to electrospray ion-trap mass spectrometry (RP-HPLC-PDA-ESI-MS/MS) and high field nuclear magnetic resonance (NMR) spectroscopy. Water-soluble metabolites from chemical classes including sugars, amino acids, organic acids, and phenolic compounds, were identified, in addition to metabolites soluble in organic solvents such as triacylglycerides, sterols, and fatty acids, and most of these were quantified. The profiling of the primary and secondary metabolites of baobab fruit and leaves addresses the limited knowledge of the chemical composition of baobab, and helps support and explain the growing evidence on its nutritional and biological properties, and provide suggestions about the possible uses of baobab fruit and leaves by food, pharmaceutical and cosmetic industries.

Eliminating interference by anthocyanins when determining the porphyrin ratio of red plant leaves

Anthocyanins (Ants) are water-soluble secondary metabolites that are responsible for red colour of plant leaves. To determine photosynthetic pigments, 80% acetone was used to extract Ants from Ant-containing leaves of test plants. However, using the 80% acetone extraction method can lead to interference between chlorophylls (Chls) and Ants. Porphyrins, such as protoporphyrin IX (PPIX), Mg-protoporphyrin IX (MgPP), and protochlorophyllide (Pchlide), are Chl biosynthetic intermediates and demonstrate photospectrometric characteristics similar to those of Chl. Although the ether/water extraction method was able to remove Ants interference when detecting porphyrins, the porphyrins extraction efficiency was lower than that of the 80% acetone extraction method. Low Ants levels interfered with individual porphyrin ratios, and the extent of the effect was correlated with Ants concentrations. We developed the three equations could eliminate interference by Ants when determining the porphyrin molecular percentage (%) and were comprehensively applied to all tested species of Ants-containing leaves.

Abstract 3483: 1H MRS characterization of the cachetic brain metabolome induced by human pancreatic pancer xenografts

Abstract The uncontrollable extreme weight loss due to cachexia results in a particularly poor quality of life causing profound weakness, listlessness, and an inability to function. A major characteristic of cachexia is accelerated skeletal muscle and fat storage wasting causing nutrient mobilization both directly as lipid and amino acids, and indirectly as ketone bodies and glucose derived from liver keto- and gluconeogenesis with systemic distribution including to the tumor through the bloodstream. Previously, we have reported the initial characterization of a myoblast optical imaging reporter that allowed real-time longitudinal monitoring of the early onset of cancer induced wasting and measured plasma metabolic changes associated with pancreatic ductal adenocarcinoma (PDAC)-induced cachexia. Here, for the first time, we have performed high-resolution quantitative 1H MR spectroscopy (MRS) of brain tissue to characterize the brain metabolome of normal mice and mice with human PDAC xenografts that induce cachexia (Pa04C cells) or are noncachectic (Panc1 cells). Male severe combined immunodeficient mice were inoculated in the right flank with cancer cells (2×106) and in the right hind leg muscle with reporter myoblasts (2×106). Once the mice were sacrificed, brains were harvested, freeze clamped and stored in -80°C until 1H MRS analysis. Dual phase solvent extraction was performed on brain tissues and MR spectra were acquired on 750 MHz (17.6T) spectrometer. As anticipated, mice with cachexia-inducing Pa04C tumors showed significant weight loss with time. For the first time, we found that brains from Pa04C tumor bearing mice exhibited a profound reduction in water soluble metabolites as compared to Panc1 and nontumor bearing normal mice. Significant decreases in neurotransmitters: γ-aminobutyric acid (GABA), N-acetyl aspartate (NAA), and taurine as well as lactate, myo-inositol, phosphocholine, glycerophosphocholine, creatine, formate, and essential amino acids: Leu, ILe, Val, and Phe were observed in brains from cachectic mice compared to noncachectic and healthy mice. Non-cachexia inducing Panc1 tumors also induced a significant decrease of brain GABA, glutamate, aspartate, total choline and tyrosine compared to normal brains. These results provide new insights into profound changes in brain metabolism during cachexia that are likely indicative of compromised CNS function and may be a major contributing factor to the systemic control of cachectic wasting. These data provide strong evidence to support investigating new metabolic interventions to reverse CNS injury and cachexia. and provide new CNS targets for early detection using in vivo MRS techniques. Acknowledgement: This work was supported by NIH R01CA193365, R35CA209960, and P30CA06973. Citation Format: Santosh Kumar Bharti, Paul T. Winnard, Yelena Mironchik, Marie-France Penet, Anirban Maitra, Zaver M. Bhujwalla. 1H MRS characterization of the cachetic brain metabolome induced by human pancreatic pancer xenografts [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3483.

Metabolite profiling and antioxidant activities of white, red, and black rice (Oryza sativa L.) grains

In the present study, several lipids- and water-soluble metabolites from white, red, and black rice were analyzed using HPLC–DAD, GC–FID, and GC–MS/MS. The quantitative data showed that black rice contains the highest amount of cyanidin (4.34 mg/g), γ-oryzanol (380.2 µg/g), total folate (39.1 µg/100 g), tocols (tocopherols and tocotrienols; 21.7 µg/g), all-E-lutein (7.14 µg/g), polyunsaturated fatty acids (37.7%), and total phenolic contents (4.88 mg gallic acid eq./g). Additionally, the ascorbic acid equivalent (AAE) antioxidant assays showed that the metabolites from black rice were potent scavengers of ABTS cations (18.99 mg AAE/g) and DPPH radicals (16.20 mg AAE/g), probably because of the presence of high contents of phenolic (e.g., anthocyanin) and non-phenolic compounds (e.g., carotenoids, tocols, and γ-oryzanols). Among the studied metabolites, the least variation was recorded for fatty acid composition. In the three types of rice grains, oleic acid (C18:1n9c) was found in the highest quantity (38.60–40.35%), followed by linoleic (LA; C18:2n6c) and palmitic acid (C16:0) (18.90–21.15%). Overall, black rice was found to be the most abundant source of nutritionally important compounds, followed by red rice and white rice. Thus, this study provides a basis for the incorporation of pigmented rice into our daily diet for potential health benefits.

Differential Effects of Quercetin and Two of Its Derivatives, Isorhamnetin and Isorhamnetin-3-glucuronide, in Inhibiting the Proliferation of Human Breast-Cancer MCF-7 Cells.

Quercetin (Que) has consistently been reported to be useful cytotoxic compound in vivo and in vitro, but little is known on its metabolites. Here, we examined and compared the cytotoxic effects of Que and its water-soluble metabolites, isorhamnetin (IS) and isorhamnetin-3-glucuronide (I3G), in human breast-cancer MCF-7 cells to uncover their tumor-inhibitory mechanisms and structure-function relationships. The results showed that Que, IS, and I3G could dose-dependently inhibit the growth of MCF-7 cells, and the cytotoxic effect was ranked as Que > IS > I3G. Furthermore, Que, IS, and I3G mediated cell-cycle arrest principally in S phase, followed by a decrease in the number of cells in G0/G1 and G2/M; moreover, 70.8, 68.9, and 49.8% of MCF-7 tumor cells entered early-phase apoptosis when treated with 100 μM Que, IS, and I3G for 48 h, respectively. Moreover, induction of apoptosis by Que, IS, and I3G was accompanied by the marginal generation of intracellular reactive oxygen species (ROS). Given these results, Que, IS, and I3G possess strong cytotoxic effects through an ROS-dependent apoptosis pathway in MCF-7 cells.

Mass spectrometry-based metabolomics and chemometric analysis of Pu-erh teas of various origins

Pu-erh tea is one of the most popular tea beverages in China. Storage time, fermentation process and origin of production affect quality and price of Pu-erh teas. High resolution mass spectrometry-based metabolomics approach, NIR combined with chemometric analysis were used to profile water soluble metabolites from raw Bingdao Pu-erh teas stored for 1–10 years and teas from various production sites. Year prediction models with good rate of recognition were established using partial least squares analysis and factor analysis. 38 characteristic compounds were identified that can be used to distinguish length of storage of Pu-erh teas. 19 characteristic compounds were found that can be used to differentiate raw and ripened teas. Cluster analysis of Pu-erh teas from different sites showed correlation between geographical distribution of the sites and composition of the water extracts. The research provides guidance for discrimination of Pu-erh teas and helps establish a healthy tea market.