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The triacylglycerol (TAG) compositions of cucumber, tomato, pumpkin, and carrot seed oils were analyzed using ultra-performance convergence chromatography (UPC2) combined with quadrupole time-of-flight mass spectrometry (Q-TOF MS). A total of 36, 42, 39, and 27 different TAGs were characterized based on their Q-TOF MS accurate molecular weight and MS2 fragment ion profiles in the cucumber, tomato, pumpkin, and carrot seed oils, respectively. Generally, different vegetable seed oils had different TAGs compositions. Among the identified fatty acids, linoleic acid was the most abundant fatty acid in cucumber, tomato, and pumpkin seed oils and the second most abundant in carrot seed oil with relative concentrations of 54.48, 48.69, 45.10, and 15.92 g/100 g total fatty acids, respectively. Oleic acid has the highest concentration in carrot seed oil and the second highest in cucumber, tomato, and pumpkin seed oils, with relative concentrations of 78.97, 18.57, 27.16, and 33.39 g/100 g total fatty acids, respectively. The chemical compositions of TAGs and fatty acids could promote understanding about the chemical profiles of certain vegetable seed oils, thus improving the potential ability to select appropriate oils with specific functions and a high nutritional value and then develop functional foods in the future.

For controlling pesticide residues in food and ensuring food safety, multiresidue methods that can monitor a wide range of pesticides in various types of foods are required for regulatory monitoring. In this study, to demonstrate the applicability of liquid chromatography&ndash, quadrupole time-of-flight mass spectrometry (LC&ndash, QTOF-MS) for quantitative and confirmatory analysis of pesticide residues in cereal grains and legumes, the LC&ndash, QTOF-MS method using full-scan acquisition was validated for 151 pesticides in brown rice, soybeans, and peanuts at a spiked level of 0.01 mg/kg. With the exception of 5 out of 151 target pesticides, sufficiently high signal intensities were obtained at 0.005 &mu, g/mL (corresponding to 0.01 mg/kg). Trueness was in the range 70&ndash, 95%, with intra- and inter-day precisions below 16% and 24%, respectively, with the exception of 7 pesticides in brown rice, 10 pesticides in soybeans, and 9 pesticides in peanuts. No interfering peaks were observed near the retention times of the target pesticides. Furthermore, information on accurate fragment-ion masses obtained by a data-independent acquisition enabled unambiguous confirmation. The results suggest that the LC-QTOF-MS method is suitable for pesticide residues&rsquo, analysis of cereal grains and legumes, and can be utilized for regulatory routine analysis.

Alismatis Rhizoma (AMR) is a well-known natural medicine with a long history in Chinese medicine and has been commonly used for treating a wide range of ailments related to dysuria, edema, nephropathy, hyperlipidaemia, diabetes, inflammation as well as tumors in clinical applications. Most beneficial effects of AMR are attributed to the presence of protostane terpenoids, the major active ingredients of Alismatis Rhizoma (AMR). In this study, a systematic high performance liquid chromatography/diode-array detector/quadrupole-time-of-flight mass spectrometry (HPLC-DAD-Q-TOF MS) and ultra-performance liquid chromatography/triple quadrupole mass spectrometry (UPLC-QqQ MS) method was developed for qualitative and quantitative analyses of the major AMR triterpenoids. First, a total of 25 triterpenoid components, including 24 known compounds and one new compound were identified by comparison with UV spectra, molecular ions and fragmentation behaviors of reference standards or the literature. Second, an efficient method was established for the rapid simultaneous determination of 14 representative triterpenoids by UPLC-QqQ MS. Forty-three batches of AMR were analyzed with linearity (r, 0.9980-0.9999), intra-day precision (RSD, 1.18%-3.79%), inter-day precision (RSD, 1.53%-3.96%), stability (RSD, 1.32%-3.97%), repeatability (RSD, 2.21%-4.25%), and recovery (98.11%-103.8%). These results indicated that new approaches combining HPLC-DAD-Q-TOF MS and UPLC-QqQ MS are applicable in the qualitative and quantitative analysis of AMR.

Evidence suggests that high-density lipoprotein (HDL) components distinct from cholesterol, such as sphingosine-1-phosphate (S1P), may account for the anti-atherothrombotic effects attributed to this lipoprotein. The current method for the determination of plasma levels of S1P as well as levels associated with HDL particles is still cumbersome an assay method to be worldwide practical. Recently, a simplified protocol based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) for the sensitive and specific quantification of plasma levels of S1P with good accuracy has been reported. This work utilized a triple quadrupole (QqQ)-based LC-MS/MS system. Here we adapt that method for the determination of plasma levels of S1P using a quadrupole time of flight (Q-Tof) based LC-MS system. Calibration curves were linear in the range of 0.05 to 2 µM. The lower limit of quantification (LOQ) was 0.05 µM. The concentration of S1P in human plasma was determined to be 1 ± 0.09 µM (n = 6). The average accuracy over the stated range of the method was found to be 100 ± 5.9% with precision at the LOQ better than 10% when predicting the calibration standards. The concentration of plasma S1P in the prepared samples was stable for 24 h at room temperature. We have demonstrated the quantification of plasma S1P using Q-Tof based LC-MS with very good sensitivity, accuracy, and precision that can used for future studies in this field.

In this study, a combination of quadrupole time-of-flight mass spectrometry (Q-TOF-MS) and linear trap quadrupole orbitrap mass spectrometry (LTQ-Orbitrap-MS) was performed to investigate the fragmentation behaviors of prenylated flavonoids (PFs) from Artocarpus plants. Fifteen PFs were selected as the model molecules and divided into five types (groups A&ndash, E) according to their structural characteristics in terms of the position and existing form of prenyl substitution in the flavone skeleton. The LTQ-Orbitrap-MSn spectra of the [M &minus, H]&minus, ions for these compounds provided a wealth of structural information on the five different types of compounds. The main fragmentation pathways of group A were the ortho effect and retro Diels&ndash, Alder (RDA), and common losses of C4H10, CO, and CO2. The compounds in group B easily lose C6H12, forming a stable structure of a 1,4-dienyl group, unlike those in group A. The fragmentation pathway for group C is characterized by obvious 1,4A&minus, 1,4B&minus, cracking of the C ring. The diagnostic fragmentation for group D is obvious RDA cracking of the C ring and the successive loss of CH3 and H2O in the LTQ-Orbitrap-MSn spectra. Fragmentation with successive loss of CO or CO2, &middot, CH3, and CH4 in the LTQ-Orbitrap-MSn spectra formed the characteristics of group E. The summarized fragmentation rules were successfully exploited to identify PFs from Artocarpus heterophyllus, a well-known Artocarpus plant, which led to the identification of a total of 47 PFs in this plant.

With the aim to discuss the similarities and differences of phytochemicals in Moringa oleifera leaves collected from China (CML) and India (IML) in mind, comparative ultra-performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry (UPLC-QTOF-MS) analysis was performed in this study. A screening analysis based on a UNIFI platform was first carried out to discuss the similarities. Next, untargeted metabolomic analysis based on multivariate statistical analysis was performed to discover the differences. As a result, a total of 122 components, containing 118 shared constituents, were characterized from CML and IML. The structure types included flavonoids, alkaloids, glyosides, organic acids and organic acid esters, iridoids, lignans, and steroids, etc. For CML, 121 compounds were characterized, among these, 18 potential biomarkers with higher contents enabled differentiation from IML. For IML, 119 compounds were characterized, among these, 12 potential biomarkers with higher contents enabled differentiation from CML. It could be concluded that both CML and IML are rich in phytochemicals and that CML is similar to IML in the kinds of the compounds it contains, except for the significant differences in the contents of some compounds. This comprehensive phytochemical profile study provides a basis for explaining the effect of different growth environments on secondary metabolites and exists as a reference for further research into or applications of CML in China.

Toosendanin is the major bioactive component of Melia toosendan Sieb. et Zucc., which is traditionally used for treatment of abdominal pain and as an insecticide. Previous studies reported that toosendanin possesses hepatotoxicity, but the mechanism remains unknown. Its bioavailability in rats is low, which indicates the hepatotoxicity might be induced by its metabolites. In this connection, in the current study, we examined the metabolites obtained by incubating toosendanin with human live microsomes, and then six of these metabolites (M1–M6) were identified for the first time by ultra-high performance liquid chromatography-quadrupole-time of flight mass spectrometry (UHPLC-Q-TOF/MS). Further analysis on the MS spectra showed M1, M2, and M3 are oxidative products and M6 is a dehydrogenation product, while M4 and M5 are oxidative and dehydrogenation products of toosendanin. Moreover, their possible structures were deduced from the MS/MS spectral features. Quantitative analysis demonstrated that M1-M5 levels rapidly increased and reached a plateau at 30 min, while M6 rapidly reached a maximal level at 20 min and then decreased slowly afterwards. These findings have provided valuable data not only for understanding the metabolic fate of toosendanin in liver microsomes, but also for elucidating the possible molecular mechanism of its hepatotoxicity.

Top-down sequencing in proteomics has come of age owing to continuous progress in LC-MS. With their high resolution and broad mass range, Quadrupole Time-of-Flight (Q-ToF) hybrid mass spectrometers equipped with electrospray ionisation source and tandem MS capability by collision-induced dissociation (CID) can be employed to analyse intact proteins and retrieve primary sequence information. To our knowledge, top-down proteomics methods with Q-ToF have only been evaluated using samples of relatively low complexity. Furthermore, the in-source CID (IS-CID) capability of Q-ToF instruments has been under-utilised. This study aimed at optimising top-down sequencing of intact milk proteins to achieve the greatest sequence coverage possible from samples of increasing complexity, assessed using nine known proteins. Eleven MS/MS methods varying in their IS-CID and conventional CID parameters were tested on individual and mixed protein standards as well as raw milk samples. Top-down sequencing results from the nine most abundant proteoforms of caseins, alpha-lactalbumin and beta-lactoglubulins were compared. Nine MS/MS methods achieved more than 70% sequence coverage overall to distinguish between allelic proteoforms, varying only by one or two amino acids. The optimal methods utilised IS-CID at low energy. This experiment demonstrates the utility of Q-ToF systems for top-down proteomics and that IS-CID could be more frequently employed.

Resina Draconis is a highly valued traditional medicine widely used in Arabia since ancient times, and it has been commonly used as an antidiarrheic, antimicrobial, antiulcer, blood circulation promoter as well as an anti-inflammatory agent. The tree source from which this medicine orignates grows extremely slowly, producing a very low yield of Resina Draconis. To meet the increasing market demand, artificial methods for stimulating Resina Draconis formation have been developed and applied. However, the chemical differences between artificially induced Resina Draconis (AIRD) and natural Resina Draconis (NRD) have been rarely studied. The aim of this research was to explore and identify the chemical constituents of AIRD and NRD using ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UHPLC-QTOF-MS/MS) based chemical profiling. A total of 56 chromatographic peaks were detected in AIRD, of these, 44 peaks have had their structures tentatively characterized based on high-resolution mass spectra (HRMS) data, fragmentation ions information, reference standards data and literature review. In total, 40 peaks were found both in AIRD and NRD. The potential chemical transformation mechanisms active in Resina Draconis during formation were explored. To the best of our knowledge, this is the first evaluation of the chemical profiles of both AIRD and NRD. Furthermore, these findings are expected to provide a rational basis for the quality assessment of AIRD and the use of AIRD as a substitute for NRD.

Xian-Ling-Gu-Bao capsule (XLGB), a famous traditional Chinese medicine prescription, is extensively used for the treatment of osteoporosis in China. However, few studies on the holistic quality control of XLGB have been reported. In this study, a reliable method using 18 representative components in XLGB was successfully established and applied to evaluate 34 batches of XLGB samples by ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF-MS). The choice of quantitative markers mostly followed four principles, i.e., absorbed components in plasma, bioactive compounds with in vitro anti-osteoporosis activity, those derived from multiple individual medicinal herbs in XLGB with multiple representative structure types, and quantitative chemical markers in the Chinese Pharmacopoeia. The results showed chemical consistency was good except for individual batches. Multivariate statistical analysis indicated that asperosaponin VI from Radix Dipsaci, epimedin C, magnoflorine, and icariin from Herba Epimedii as well as timosaponin BII from Rhizoma Anemarrhenae varied significantly in multiple samples, which hinted an assay for these four components should be completed during all of the manufacturing processes. Taken together, this study provided a feasible method for holistic quality control of XLGB by multiple chemical markers, which could play a vital role in guaranteeing the safety, effectiveness, and controllability of administering the capsules as a medication in clinics.