Neutral Loss Scan - Based Strategy for Integrated Identification of Amorfrutin Derivatives, New Peroxisome Proliferator-Activated Receptor Gamma Agonists, from Amorpha Fruticosa by UPLC-QqQ-MS/MS and UPLC-Q-TOF-MS

Nitrophenols in the environment: An update on pretreatment and analysis techniques since 2017

Nitrophenols, a versatile intermediate, have been widely used in leather, medicine, chemical synthesis, and other fields. Because these components are widely applied, they can enter the environment through various routes, leading to many hazards and toxicities. There has been a recent surge in the development of simple, rapid, environmentally friendly, and effective techniques for determining these environmental pollutants. This review provides a comprehensive overview of the latest research progress on the pretreatment and analysis methods of nitrophenols since 2017, with a focus on environmental samples. Pretreatment methods include liquid-liquid extraction, solid-phase extraction, dispersive extraction, and microextraction methods. Analysis methods mainly include liquid chromatography-based methods, gas chromatography-based methods, supercritical fluid chromatography. In addition, this review also discusses and compares the advantages/disadvantages and development prospects of different pretreatment and analysis methods to provide a reference for further research.

Chemical derivatization strategies for enhancing the HPLC analytical performance of natural active triterpenoids

Triterpenoids widely exist in nature, displaying a variety of pharmacological activities. Determining triterpenoids in different matrices, especially in biological samples holds great significance. High-performance liquid chromatography (HPLC) has become the predominant method for triterpenoids analysis due to its exceptional analytical performance. However, due to the structural similarities among botanical samples, achieving effective separation of each triterpenoid proves challenging, necessitating significant improvements in analytical methods. Additionally, triterpenoids are characterized by a lack of ultraviolet (UV) absorption groups and chromophores, along with low ionization efficiency in mass spectrometry. Consequently, routine HPLC analysis suffers from poor sensitivity. Chemical derivatization emerges as an indispensable technique in HPLC analysis to enhance its performance. Considering the structural characteristics of triterpenoids, various derivatization reagents such as acid chlorides, rhodamines, isocyanates, sulfonic esters, and amines have been employed for the derivatization analysis of triterpenoids. This review comprehensively summarized the research progress made in derivatization strategies for HPLC detection of triterpenoids. Moreover, the limitations and challenges encountered in previous studies are discussed, and future research directions are proposed to develop more effective derivatization methods.

Role of simulated in vitro gastrointestinal digestion on biotransformation and bioactivity of astragalosides from Radix Astragali

Radix Astragali (RA) is commonly used in Asian herbal therapy or food supply, and astragalosides and flavonoids are its major components with diverse pharmaceutical effects. To provide new information on the potential cardiovascular benefits of RA administered orally, the bioaccessibility of these compounds with relevant in vitro digestion parameters was determined for four digestion phases (oral, gastric, small and large intestines) by ultrahigh-performance liquid chromatography quadrupole time-of-flight-mass spectrometry (UPLC-Q-TOF/MS). Meanwhile, we compared the effects of digestion products on advanced glycation end products (AGEs)-induced intracellular reactive oxygen species (ROS) levels in a human arterial endothelial cells (HAECs) model, and studied the potential of RA against oxidative stress-related cardiovascular disease. The changes of saponins and flavonoids composition and antioxidant activity after digestion in intestines were mainly due to the astragaloside IV (AS-IV) biosynthesis involving saponins acetyl isomerization and deacetylation, and the flavonoid glycosides converted to aglycone by deglycosylation processes. All these results suggest that acetyl biotransformation of RA in small intestine directly influenced the response to oxidative stress, and might provide a reference for elucidation of the multi-component action after oral RA in cardiovascular health care.

UPLC-Q-TOF-MS/MS Analysis of Seco-Sativene Sesquiterpenoids to Detect New and Bioactive Analogues From Plant Pathogen Bipolaris sorokiniana

Seco-sativene sesquiterpenoids are an important member of phytotoxins and plant growth regulators isolated from a narrow spectrum of fungi. In this report, eight seco-sativene sesquiterpenoids (1-8) were first analyzed using the UPLC-Q-TOF-MS/MS technique in positive mode, from which their mass fragmentation pathways were suggested. McLafferty rearrangement, 1,3-rearrangement, and neutral losses were considered to be the main fragmentation patterns for the [M+1]+ ions of 1-8. According to the structural features (of different substitutes at C-1, C-2, and C-13) in compounds 1-8, five subtypes (A-E) of seco-sativene were suggested, from which subtypes A, B/D, and E possessed the diagnostic daughter ions at m/z 175, 189, and 203, respectively, whereas subtype C had the characteristic daughter ion at m/z 187 in the UPLC-Q-TOF-MS/MS profiles. Based on the fragmentation patterns of 1-8, several known compounds (1-8) and two new analogues (9 and 10) were detected in the extract of plant pathogen fungus Bipolaris sorokiniana based on UPLC-Q-TOF-MS/MS analysis, of which 1, 2, 9, and 10 were then isolated and elucidated by NMR spectra. The UPLC-Q-TOF-MS/MS spectra of these two new compounds (9 and 10) were consistent with the fragmentation mechanisms of 1-8. Compound 1 displayed moderate antioxidant activities with IC50 of 0.90 and 1.97 mM for DPPH and ABTS+ scavenging capacity, respectively. The results demonstrated that seco-sativene sesquiterpenoids with the same subtypes possessed the same diagnostic daughter ions in the UPLC-Q-TOF-MS/MS profiles, which could contribute to structural characterization of seco-sativene sesquiterpenoids. Our results also further supported that UPLC-Q-TOF-MS/MS is a powerful and sensitive tool for dereplication and detection of new analogues from crude extracts of different biological origins.

Use of Diagnostic Ions for the Detection of Fentanyl Analogs in Human Matrices by LC-QTOF

To combat the ongoing opioid epidemic, our laboratory has developed and evaluated an approach to detect fentanyl analogs in urine and plasma by screening LC-QTOF MS/MS spectra for ions that are diagnostic of the core fentanyl structure. MS/MS data from a training set of 142 fentanyl analogs were used to select the four product ions and six neutral losses that together provided the most complete coverage (97.2%) of the training set compounds. Furthermore, using the diagnostic ion screen against a set of 49 fentanyl analogs not in the training set resulted in 95.9% coverage of those compounds. With this approach, lower reportable limits for fentanyl and a subset of fentanyl-related compounds range from 0.25 to 2.5 ng/mL in urine and 0.5 to 5.0 ng/mL in plasma. This innovative processing method was applied to evaluate simulated exposure samples of remifentanil and carfentanil in water and their metabolites remifentanil acid and norcarfentanil in urine. This flexible approach enables a way to detect emerging fentanyl analogs in clinical samples.

Jiangzhi Granule attenuates non-alcoholic steatohepatitis by suppressing TNF/NFκB signaling pathway-a study based on network pharmacology

Jiangzhi Granule is a commonly used traditional Chinese medicine for treating non-alcoholic fatty liver disease. However, its key ingredients and underlying mechanisms for attenuating nonalcoholic steatohepatitis (NASH) remain unclear. To address this issue, UPLC-TOF-MS based chemical profiling, network pharmacology and animal experimental validation were employed. First, a total of 56 main ingredients of Jiangzhi Granule and 38 ingredients in the blood and liver (after oral administration) were identified. Then, 170 potential targets of the absorbed ingredients and 50 targets of NASH were identified, and 10 overlapped genes were identified as candidate targets of Jiangzhi Granule for NASH treatment. A Jiangzhi Granule-ingredients-targets-disease network was constructed using Cytoscape software, which included eight main ingredients (such as emodin, resveratrol and quercetin) and 10 candidate targets (such as TNF, IL6 and CCL2). Functional enrichment indicated that the candidate targets were enriched in multiple pathways (such as the TNF signaling pathway). Furthermore, a NASH mice model was constructed and intervened with Jiangzhi Granule. The results revealed that Jiangzhi Granule could ameliorate NASH characteristics, such as histopathological changes and liver cholesterol level. Meanwhile, Jiangzhi Granule significantly decreased the mRNA and protein expression of TNFα in NASH mice liver, suppressed NFκB activation, and inhibited the expression of macrophage activation marker F4/80 and M1-type polarization marker CD11b/CD11c. ELISA assay indicated that Jiangzhi Granule reduced pro-inflammatory cytokines (including TNFα, IL-1β and IL-6) in the liver. Collectively, our results suggested that Jiangzhi Granule could attenuate NASH by suppressing TNF/NFκB signaling mediated macrophage M1-type polarization.

A Practical Method for Determination of Nine Nucleosides in Tricholoma matsutake by UPLC/MS and Quantitative Analysis of Multicomponents Using Single Marker Method

Nucleosides can be used as quality evaluation indicators of Tricholoma matsutake. In this work, a new ultra-performance liquid chromatography-tandem mass spectrometry (UPLC/MS) strategy for quantitative analysis of multiple components using a single marker (QAMS) was proposed to determine nine nucleosides (adenosine, cytidine, guanosine, inosine, uridine, 2'-deoxyadenosine, 2'-deoxycytidine, 2'-deoxyguanosine, and 2'-deoxyuridine) in T. matsutake. Guanosine was set as the internal reference substance, whose content in T. matsutake was determined using the conventional external standard method. Relative correction factors (RCFs) between guanosine and eight other nucleosides were measured. The concentrations of the eight components were calculated with the obtained RCFs by QAMS. An ultrasonic extraction method is used for sample preparation. This method was validated to be sensitive, precise, and accurate with the LODs of 0.31-1.9 ng, the overall intraday and interday variations less than 4.08%, and the overall recovery over 89.0%. The correlation coefficients (r ²) of the calibration curves were higher than 0.9918. The values of vector angle analysis were above 0.99845, which indicates no significant differences between the conventional external standard method and the present QAMS method. As far as we know, this is also the first report of UPLC/MS analysis of nucleoside compounds by QAMS, providing an efficient and feasible quality assessment method for other natural products containing nucleosides.

Tri- and dipeptides identification in whey protein and porcine liver protein hydrolysates by fast LC-MS/MS neutral loss screening and de novo sequencing

We describe a fast (5 min) liquid chromatography tandem mass spectrometry method (LC-MS/MS) based on a 46 Da neutral loss of formic acid (H₂ O and CO) to identify tri- and dipeptides (DIPEP) in whey protein and porcine liver protein hydrolysates and confirmed by further de novo sequencing. Sample solutions were acidified to favor [dipep + H]⁺ ions, and a m/z range of 50-300 was used to improve sensitivity. All dipeptide candidates were selected based on all possibilities of the 20 amino acid combinations, and their collision-induced dissociation fragments were screened via de novo sequencing. To determine their biological activities, sequenced dipeptides were compared with the Biopep database and other data from literature. Altogether, 18 dipeptides and 7 tripeptides were identified from the whey protein hydrolysate; they seemed to be broadly active, and peptides were identified as active dipeptidyl peptidase IV inhibitors and active angiotensin-converting enzyme (ACE), according to available information. Porcine liver hydrolysate showed 14 dipeptides which exhibit similar biological activities to whey protein hydrolysate.

Determination of Flavonoid Glycosides by UPLC-MS to Authenticate Commercial Lemonade

So far, there is no report on the quality evaluation of lemonade available in the market. In this study, a sample preparation method was developed for the determination of flavonoid glycosides by ultra-performance liquid chromatography–mass spectrometry (UPLC-MS) based on vortex-assisted dispersive liquid-liquid microextraction. First, potential flavonoids in lemonade were scanned and identified by ultra-performance liquid chromatography–time of flight mass spectrometry (UPLC-TOF/MS). Five flavonoid glycosides were identified as eriocitrin, narirutin, hesperidin, rutin, and diosmin according to the molecular formula provided by TOF/MS and subsequent confirmation of the authentic standard. Then, an ultra-performance liquid chromatography–triple quadrupole mass spectrometry (UPLC-QqQ/MS) method was developed to determine these five flavonoid glycosides in lemonade. The results showed that the content of rutin in some lemonade was unreasonably high. We suspected that many illegal manufacturers achieved the goal of low-cost counterfeiting lemonade by adding rutin. This suggested that it was necessary for relevant departments of the state to make stricter regulations on the quality standards of lemonade beverages.

Quality Evaluation of Tricholoma matsutake Based on the Nucleic Acid Compounds by UPLC-TOF/MS and UPLC-QqQ/MS

So far, there has been no quality evaluation of Tricholoma matsutake. Nucleic acid compounds are a kind of functional ingredient in T. matsutake that is beneficial to human health. In this study, a UPLC-TOF/MS method was first used to scan and identify the potential nucleic acid compounds in T. matsutake. Based on the calculation of the molecular formula and subsequent confirmation by authentic standards, 15 nucleic acid compounds were unambiguously identified: adenosine, cytidine, guanosine, inosine, thymidine, uridine, xanthosine dehydrate, 2'-deoxyadenosine, 2'-deoxycytidine, 2'-deoxyguanosine, 2'-deoxyuridine, adenosine 5'-monophosphate, cytidine 5'-monophosphate, guanosine 5'-monophosphate, and uridine 5'-monophosphate. Then, a UPLC-QqQ/MS method was developed for the subsequent quantitative analysis. After validating the limits of quantification, detection, precision, repeatability, and recovery through a calibration curve, the content of 15 nucleic acid compounds was determined by the proposed UPLC-QqQ/MS method in 80 T. matsutake samples collected from different regions in Sichuan province, Southwest China. After the statistical analysis, we suggest that the total content of nucleic acid compounds in the qualified T. matsutake should be higher than 24.49 mg/100 g. The results indicated that the combined use of UPLC-TOF/MS and UPLC-QqQ/MS is efficient for fast identification and determination of nucleic acid compounds to comprehensively evaluate the quality of T. matsutake.

UPLC-QqQ/MS combined with similarity assessment of 17 nucleic acid constituents in 147 edible fungi from Sichuan Basin, China

Nucleic acid constituents are the main functional ingredients in edible fungi, therefore understanding the nucleic acid constituents of edible fungi often eaten on the table by the Chinese people is of significant value. In this study, Sichuan Provincial Center for Disease Control and Prevention collected 147 samples of edible fungi (including certain species that the Chinese often eat) from different parts of the Sichuan Basin. A new UPLC-QqQ/MS method has been developed to determine the 17 nucleic acid constituents in these 147 samples, including guanosine, adenosine, uridine, cytidine, inosine, thymidine, xanthosine dehydrate, 2'-deoxyguanosine, 2'-deoxyadenosine, 2'-deoxyuridine, 2'-deoxycytidine, 2'-deoxyinosine, guanosine 5'-monophosphate, adenosine 5'-monophosphate, uridine 5'-monophosphate, cytidine 5'-monophosphate, and inosine 5'-monophosphate. Finally, similarity assessment of the main edible fungus was performed using vectorial angle cosine method, and hierarchical cluster analysis was used to classify all the 147 samples. The results showed that some edible fungi have high similarities, especially in Lentinula edodes (Berk.) Pegler, the monogenic nucleotides content of which (55.84 ± 8.4 mg/100 g) is far greater than any other edible fungus, which is directly related to its taste. For quality control, this paper proposed to use the reference values of total nucleic acid compounds in edible fungi computed by percentile threshold method. This is the first time a comprehensive evaluation of nucleic acid constituents of different edible fungi of daily consumption was conducted for a large region, and the results is conducive to the quality evaluation and quality control of edible fungus.

Optimization of Vortex-Assisted Dispersive Liquid-Liquid Microextraction for the Simultaneous Quantitation of Eleven Non-Anthocyanin Polyphenols in Commercial Blueberry Using the Multi-Objective Response Surface Methodology and Desirability Function Approach

In the present study, 11 non-anthocyanin polyphenols, gallic acid, protocatechuate, vanillic acid, syringic acid, ferulic acid, quercetin, catechin, epicatechin, epigallocatechin gallate, gallocatechin gallate and epicatechin gallate-were firstly screened and identified from blueberries using an ultra performance liquid chromatography⁻time of flight mass spectrography (UPLC-TOF/MS) method. Then, a sample preparation method was developed based on vortex-assisted dispersive liquid-liquid microextraction. The microextraction conditions, including the amount of ethyl acetate, the amount of acetonitrile and the solution pH, were optimized through the multi-objective response surface methodology and desirability function approach. Finally, an ultra performance liquid chromatography⁻triple quadrupole mass spectrography (UPLC-QqQ/MS) method was developed to determine the 11 non-anthocyanin polyphenols in 25 commercial blueberry samples from Sichuan province and Chongqing city. The results show that this new method with high accuracy, good precision and simple operation characteristics, can be used to determine non-anthocyanin polyphenols in blueberries and is expected to be used in the analysis of other fruits and vegetables.

A efficient method to identify cardioprotective components of Astragali Radix using a combination of molecularly imprinted polymers-based knockout extract and activity evaluation

Although herb medicines have become the major source for new drug discovery, many of them are largely under-explored due to the purity-activity relationship. Efficient identification of bioactive compounds in conventional stepwise separation and isolation has not yet been elucidated. Therefore, we proposed a new separation strategy for holism understanding of herb pharmacology using molecularly imprinted polymers (MIPs). Astragali Radix (AR), important in traditional Chinese medicine, was chosen in this study for multicomponent knockout followed by bioactivity evaluation. We prepared calycosin molecularly imprinted polymers (calycosin-MIPs) which could selectively recognize flavonoid aglycons in AR. The molecular selectivity of calycosin-MIPs as a critical parameter was evaluated using the template and other high content compounds in AR. Based on it, using the calycosin-MIPs material via solid-phase extraction procedures was applied for the knockout of flavonoid aglycons in AR. Finally, hypoxia/reoxygenation model in H9c2 cells was used to evaluate the activity of the AR extract before and after knockout. The results showed that calycosin-MIPs as recognition materials for flavonoid aglycons in AR are applied in one-step separation with high selectivity and tunability. The subextract in the absence of flavonoid aglycons has been demonstrated to clarify the cardio-protective components of AR. In conclusion, this proof-of-principle study is the first one showing that molecular imprinting technology coupled with a bioassay can be used to explore the bioactive variability from the perspective of multicomponent separation of herbal medicine.