Association between monocyte-to-high-density lipoprotein-cholesterol ratio and gallstones in U.S. adults: findings from the National Health and Nutrition Examination Survey 2017-2020.

BACKGROUND: Studies have indicated that monocyte-to-high-density lipoprotein cholesterol ratio (MHR) can be a reliable indicator of various diseases. However, the association between MHR and gallstone prevalence remains unclear. Therefore, this study aimed to explore any potential association between MHR and gallstone prevalence. METHODS: This study used data from the National Health and Nutrition Examination Survey (NHANES) 2017-March 2020. MHR was calculated as the monocyte count ratio to high-density lipoprotein cholesterol levels. Multiple logistic regression models, Cochran-Armitage trend test, and subgroup analyses were used to examine the association between MHR and gallstones. RESULTS: This study included 5907 participants, of whom 636 (10.77%) were gallstone formers. The study participants had a mean age of 50.78 ± 17.33 years. After accounting for multiple covariables, the multiple logistic regression model showed a positive linear association between MHR and gallstone odds. The subgroup analyses and interaction testing results revealed that the association between MHR and gallstones was statistically different across strata, including sex, smoking, asthma, and hypertension. CONCLUSIONS: Gallstone prevalence positively associated with elevated MHR, indicating that MHR can be employed as a clinical indicator to assess gallstone prevalence.

CBLC promotes the development of colorectal cancer by promoting ABI1 degradation to activate the ERK signaling pathway.

CBLC (CBL proto-oncogene C) is an E3 ubiquitin protein ligase that plays a key role in cancers. However, the function and mechanism of CBLC in colorectal cancer (CRC) has not been fully elucidated. The aim of this study was to investigate the function of CBLC in CRC and its underlying molecular mechanism. High CBLC levels were certified in tumor tissues of CRC patients, and its expression was positively associated with TNM stage. Next, we explored the role of CBLC in CRC using gain or loss of function. For biological function analysis, CCK-8 cell proliferation, colony formation, flow cytometry, scratch, and transwell assays collectively suggested that CBLC overexpression promoted cell proliferation, cell cycle progression, migration and invasion. As observed, CBLC knockdown exhibited exactly opposite effects, resulting in impaired tumorigenicity in vitro. Xenograft studies displayed that CBLC overexpression accelerated tumor growth and promoted tumor metastasis to the lung, while the inhibitory effects of CBLC knockdown on tumorigenicity and metastasis ability of CRC cells was also confirmed. Furthermore, the molecular mechanism of CBLC in CRC was explored. CBLC induced the activation of ERK signaling pathway, further leading to its pro-tumor role. Notably, CBLC decreased ABI1 (Abelson interactor protein-1, a candidate tumor suppressor) protein levels through its ubiquitin ligase activity, while ABI1 upregulation abolished the effects of CBLC on the tumorigenesis of CRC. Taken together, these results demonstrate that CBLC acts as a tumor promoter in CRC through triggering the ubiquitination and degradation of ABI1 and activating the ERK signaling pathway. CBLC may be a potential novel target for CRC.

A new Frontier in electric load forecasting: The LSV/MOPA model optimized by modified orca predation algorithm.

Electric load forecasting is a vital task for energy management and policy-making. However, it is also a challenging problem due to the complex and dynamic nature of electric load data. In this paper, a novel technique, called LSV/MOPA, has been proposed for electric load forecasting. The technique is a hybrid model that combines the advantages of Long Short-Term Memory (LSTM) and Support Vector Regression (SVR), two powerful artificial intelligence algorithms. The hybrid model is further optimized by a newly Modified Orca Predation Algorithm (MOPA), which enhances the forecasting accuracy and efficiency. The LSV/MOPA model has been applied to historical electric load data from South Korea, covering four regions and 20 years. The LSV/MOPA model has been compared with other state-of-the-art forecasting techniques, including SVR/FFA, LSTM/BO, LSTM-SVR, and CNN-LSTM. The results show that the LSV/MOPA model with minimum average mean absolute percentage deviation error, including 365 in northern region, 12.8 in southern region, 8.6 in central region, and 30.8 in eastern region, provides the best fitting and outperforms the other techniques in terms of the Mean Absolute Percentage Deviation (MAPD) index, achieving lower values for all regions and years. The LSV/MOPA model also exhibits faster convergence and better generalization than the other techniques. This study demonstrates the effectiveness and superiority of the LSV/MOPA model for electric load forecasting and suggests its potential applications in other sectors where accurate forecasting is crucial.

Causal relationships between coffee intake, apolipoprotein B and gastric, colorectal, and esophageal cancers: univariable and multivariable Mendelian randomization.

PURPOSE: Coffee intake and apolipoprotein B levels have been linked to gastric, colorectal, and esophageal cancers in numerous recent studies. However, whether these associations are all causal remains unestablished. This study aimed to assess the potential causal associations of apolipoprotein B and coffee intake with the risk of gastric, colorectal, and esophageal cancers using Mendelian randomization analysis. METHODS: In this study, we utilized a two-sample Mendelian randomization analysis to access the causal effects of coffee intake and apolipoprotein B on gastric, colorectal, and esophageal cancers. The summary statistics of coffee intake (n = 428,860) and apolipoprotein B (n = 439,214) were obtained from the UK Biobank. In addition, the summary statistics of gastric cancer, colorectal cancer, and esophageal cancer were obtained from the FinnGen biobank (n = 218,792). Inverse variance weighted, MR-Egger, weighted median, and weighted mode were applied to examine the causal relationship between coffee intake, apolipoprotein B and gastric, colorectal, and esophageal cancers. MR-Egger intercept test, Cochran's Q test, and leave-one-out analysis were performed to evaluate possible heterogeneity and pleiotropy. Steiger filtering and bidirectional mendelian randomization analysis were performed to evaluate the possible reverse causality. RESULTS: The result of the inverse variance weighted method indicated that apolipoprotein B levels were significantly associated with a higher risk of gastric cancer (OR = 1.392, 95% CI 1.027-1.889, P = 0.0333) and colorectal cancer (OR = 1.188, 95% CI 1.001-1.411, P = 0.0491). Furthermore, multivariable Mendelian randomization analysis also revealed a positive association between apolipoprotein B levels and colorectal cancer risk, but the effect of apolipoprotein B on gastric cancer risk disappeared after adjustment of coffee intake, body mass index or lipid-related traits. However, we did not discover any conclusive evidence linking coffee intake to gastric, colorectal, or esophageal cancers. CONCLUSIONS: This study suggested a causal association between genetically increased apolipoprotein B levels and higher risk of colorectal cancer. No causal relationship was observed between coffee intake and gastric, colorectal, or esophageal cancers.

Construction of Low-Cost Z-Scheme Heterojunction Cu2O/PCN-250 Photocatalysts Simultaneously for the Enhanced Photoreduction of CO2 to Alcohols and Photooxidation of Water.

Solar-driven high-efficiency conversion of CO2 with water vapor into high-value-added alcohols is a promising approach for reducing CO2 emissions and achieving carbon neutrality. However, the rapid recombination of photogenerated carriers and low CO2 adsorption capacity of photocatalysts are usually the factors that limit their applicability. Herein, a series of low-cost Z-scheme heterostructures Cu2O/PCN-250-x are constructed by in situ growth of ultrasmall Cu2O nanoparticles on PCN-250. A systematic investigation revealed that there is a strong interaction between Cu2O nanoparticles and PCN-250. The resulting Cu2O/PCN-250-2 exhibits excellent photogenerated carrier separation efficiency and CO2 adsorption capacity, which dramatically promote the conversion of CO2 into alcohols. Notably, the total yield of 268 µmol gcat-1 for the production of CH3OH and CH3H2OH is superior to that of isolated PCN-250 and Cu2O. This study provides a new perspective for the design of a Cu2O nanoparticle/metal-organic framework Z-scheme heterojunction for the reduction of CO2 to alcohols with water vapor.

Strategy and mechanisms of sulfamethoxazole removal from aqueous systems by single and combined Shewanella oneidensis MR-1 and nanoscale zero-valent iron-enriched biochar.

Sulfamethoxazole (SMX, a sulfonamide antibiotic) is ubiquitously present in various aqueous systems, which can accelerate the spread of antibiotic resistance genes, induce genetic mutations, and even disrupt the ecological equilibrium. Considering the potential eco-environmental risk of SMX, this study explored an effective technology using Shewanella oneidensis MR-1 (MR-1) and nanoscale zero-valent iron-enriched biochar (nZVI-HBC) to remove SMX from aqueous systems with different pollution levels (1-30 mg·L-1). SMX removal by nZVI-HBC and nZVI-HBC + MR-1 (55-100 %) under optimal conditions (iron/HBC ratio of 1:5, 4 g·L-1 nZVI-HBC, and 10 % v/v MR-1) was more effective than its removal by MR-1 and biochar (HBC) (8-35 %). This was due to the catalytic degradation of SMX in the nZVI-HBC and nZVI-HBC + MR-1 reaction systems because of accelerated electron transfer during oxidation of nZVI and reduction of Fe(III) to Fe(II). When SMX concentration was lower than 10 mg·L-1, nZVI-HBC + MR-1 effectively removed SMX (removal rate of approximately 100 %) when compared to nZVI-HBC (removal rate of 56-79 %). In addition to oxidation degradation of SMX by nZVI in the nZVI-HBC + MR-1 reaction system, MR-1-driven dissimilatory iron reduction accelerated electron transfer to SMX, thereby enhancing reductive degradation of SMX. However, a considerable decline in SMX removal from the nZVI-HBC + MR-1 system (42 %) was observed when SMX concentrations ranged 15-30 mg·L-1, which was due to the toxicity of accumulated degradation products of SMX. A high interaction probability between SMX and nZVI-HBC promoted the catalytic degradation of SMX in the nZVI-HBC reaction system. The results of this study provide promising strategies and insights for enhancing antibiotic removal from aqueous systems with different pollution levels.

Discovery of novel ascorbic acid derivatives and other metabolites in fruit of Rosa roxburghii Tratt through untargeted metabolomics and feature-based molecular networking.

Fruit of Rosa roxburghii Tratt (FRR) is widely used in functional food industry while short of metabolites research. Herein, we firstly identified 251 metabolites in FRR based on untargeted liquid chromatography-mass spectrometry (LC-MS) approach. Then, 42 differential compounds were sought out to avoid the confusing use of FRR and fruit of R. sterilis S. D. Shi (FRS), and FRR was evaluated exhibiting higher biofunction potential. Moreover, a quantitative LC-MS approach was established to determine the contents of 3 ascorbyl hexosides, and FRR with higher contents should be better source than FRS. Additionally, 17 ascorbic acid (AA) derivatives formed by conjugation of ascorbyl unit with organic acids, flavonoids, or glucuronic acid were also discovered in FRR through characteristic ions of AA and feature-based molecular networking (FBMN), enlightening that AA derivatives were not limited to ascorbyl glycosides. This study provided abundant metabolites information of FRR, laying the basis for exploitation of FRR.

Evaluating the role of IDO1 macrophages in immunotherapy using scRNA-seq and bulk-seq in colorectal cancer.

Background: Macrophage infiltration is crucial for colorectal cancer (CRC) immunotherapy. Detailed classification of macrophage subsets will facilitate the selection of patients suitable for immunotherapy. However, the classification of macrophages in CRC is not currently detailed. Methods: In this study, we combined single-cell RNA sequencing (scRNA-seq) and bulk-seq to analyze patients with colorectal cancer. scRNA-seq data were used to study cell-cell communication and to differentiate immune-infiltrating cells and macrophage subsets. Bulk-seq data were used to further analyze immune infiltration, clinical features, tumor mutational burden, and expression of immune checkpoint molecules in patients with CRC having different macrophage subsets. Results: Seven macrophage subpopulations were identified, among which indoleamine 2,3 dioxygenase 1 (IDO1) macrophages had the most significant difference in the degree of infiltration among normal, microsatellite-unstable, and microsatellite-stable populations. We then performed gene set variation analysis using 12 marker genes of IDO1 macrophages and divided the patients into two clusters: high-IDO1 macrophages (H-IDO1M) and low-IDO1 macrophages (L-IDO1M). H-IDO1M showed higher infiltration of immune cells, higher expression of immune checkpoints, and less advanced pathological stages than L-IDO1M (p < 0.05). Conclusions: This study elucidated that IDO1-macrophage-based molecular subtypes can predict the response to immunotherapy in patients with CRC. The results provide new insights into tumor immunity and help in clinical decisions regarding designing effective immunotherapy for these patients.

Identification of Energy Metabolism-Related Gene Signatures From scRNA-Seq Data to Predict the Prognosis of Liver Cancer Patients.

The increasingly common usage of single-cell sequencing in cancer research enables analysis of tumor development mechanisms from a wider range of perspectives. Metabolic disorders are closely associated with liver cancer development. In recent years, liver cancer has been evaluated from different perspectives and classified into different subtypes to improve targeted treatment strategies. Here, we performed an analysis of liver cancer from the perspective of energy metabolism based on single-cell sequencing data. Single-cell and bulk sequencing data of liver cancer patients were obtained from GEO and TCGA/ICGC databases, respectively. Using the Seurat R package and protocols such as consensus clustering analysis, genes associated with energy metabolism in liver cancer were identified and validated. An energy metabolism-related score (EM score) was established based on five identified genes. Finally, the sensitivity of patients in different scoring groups to different chemotherapeutic agents and immune checkpoint inhibitors was analyzed. Tumor cells from liver cancer patients were found to divide into nine clusters, with cluster 4 having the highest energy metabolism score. Based on the marker genes of this cluster and TCGA database data, the five most stable key genes (ADH4, AKR1B10, CEBPZOS, ENO1, and FOXN2) were identified as energy metabolism-related genes in liver cancer. In addition, drug sensitivity analysis showed that patients in the low EM score group were more sensitive to immune checkpoint inhibitors and chemotherapeutic agents AICAR, metformin, and methotrexate.

Chemical profiling and antioxidants screening from natural products: using CiNingJi as an example.

Natural products with good antioxidative properties have been paid increased attention globally. However, due to its chemical complexity, it is difficult to find out its antioxidative compounds. Herein, the chemical profiling and antioxidant capacity of CiNingJi (CNJ) were analyzed, as an example. By using UHPLC-Q-TOF/MS, a total of 82 compounds were tentatively deduced. Furthermore, its free radical scavenging capacity was assessed by different in vitro spectrophotometric-based assays. The result showed that one ingredient, Rosa roxburghii, plays a critical role in its antioxidant activity. In addition, 18 potential antioxidants were screened out in CNJ by comparing the difference of it with and without DPPH reaction. They were identified mainly as catechin, ellagic acid, kajiichigoside F1, and their derivatives or isomers. With the further quantification of major found antioxidants, our results may provide some knowledge on predicting the antioxidative compounds of natural products. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-022-01049-4.

Update of Indoles: Promising molecules for ameliorating metabolic diseases.

Obesity and metabolic disorders have gradually become public health-threatening problems. The metabolic disorder is a cluster of complex metabolic abnormalities which are featured by dysfunction in glucose and lipid metabolism, and results from the increasing prevalence of visceral obesity. With the core driving factor of insulin resistance, metabolic disorder mainly includes type 2 diabetes mellitus (T2DM), micro and macro-vascular diseases, non-alcoholic fatty liver disease (NAFLD), dyslipidemia, and the dysfunction of gut microbiota. Strategies and therapeutic attention are demanded to decrease the high risk of metabolic diseases, from lifestyle changes to drug treatment, especially herbal medicines. Indole is a parent substance of numerous bioactive compounds, and itself can be produced by tryptophan catabolism to stimulate glucagon-like peptide-1 (GLP-1) secretion and inhibit the development of obesity. In addition, in heterocycles drug discovery, the indole scaffold is primarily found in natural compounds with versatile biological activity and plays a prominent role in drug molecules synthesis. In recent decades, plenty of natural or synthesized indole deriviatives have been investigated and elucidated to exert effects on regulating glucose hemeostasis and lipd metabolism. The aim of this review is to trace and emphasize the compounds containing indole scaffold that possess immense potency on preventing metabolic disorders, particularly T2DM, obesity and NAFLD, along with the underlying molecular mechanisms, therefore facilitate a better comprehension of their druggability and application in metabolic diseases.

YAP derived circ-LECRC functions as a "brake signal" to suppress hyperactivation of oncogenic YAP signalling in colorectal cancer.

Accumulating evidence indicates that circular RNAs (circRNAs) play vital roles in tumorigenesis by modulating gene expression. However, the molecular mechanisms underlying the functions of circRNAs remain largely unknown. Here, we demonstrated that a Yes1 associated transcriptional regulator (YAP1)-derived circRNA, circ-LECRC (circRNA low expressed in CRC), was significantly downregulated in colorectal cancer (CRC). High expression of circ-LECRC positively correlated with a lower TNM stage and good prognosis in CRC patients. Circ-LECRC overexpression significantly inhibited CRC cell proliferation, migration, and invasion and promoted apoptosis (P < 0.05). Additionally, we performed xenograft and lung metastasis experiments by injecting CRC cells into nude mice to mechanistically demonstrate that circ-LECRC directly binds to miR-135b-5p and relieve the suppression of its target, Krüppel-like factor 4 (KLF4). Furthermore, we found that both circ-LECRC and KLF4 inhibited YAP1 hyperactivation, which downregulates the expression of the downstream genes of the YAP1 pathway, such as EGFR, MYC, BIRC5, and CTGF. In summary, circ-LECRC regulates KLF4 expression by functioning as a competing endogenous RNA and serves as a "brake signal" to suppress hyperactivation of oncogenic YAP signalling, leading to tumour growth inhibition in CRC.

Establishment and Validation of a Genetic Label Associated With M2 Macrophage Infiltration to Predict Survival in Patients With Colon Cancer and to Assist in Immunotherapy.

BACKGROUND: Colon cancer is a malignant tumor with high morbidity and mortality. Researchers have tried to interpret it from different perspectives and divided it into different subtypes to facilitate individualized treatment. With the rise in the use of immunotherapy, its value in the field of tumor has begun to emerge. From the perspective of immune infiltration, this study classified colon cancer according to the infiltration of M2 macrophages in patients with colon cancer and further explored the same. METHODS: Cibersort algorithm was used to analyze the level of immune cell infiltration in patients with colon cancer in The Cancer Genome Atlas (TCGA) database. Weighted gene co-expression network analysis (WGCNA), Consensus Clustering analysis, Lasso analysis, and univariate Kaplan-Meier analysis were used to screen and verify the hub genes associated with M2 macrophages. Principal component analysis (PCA) was used to establish the M2 macrophage-related score (M2I Score). The correlation between M2I Score and somatic cell variation and microsatellite instability (MSI) were analyzed. Furthermore, the correlation between M2 macrophage score and differences in immunotherapy sensitivity was also explored. RESULTS: M2 macrophage infiltration was associated with poor prognosis. Four hub genes (ANKS4B, CTSD, TIMP1, and ZNF703) were identified as the progression-related genes associated with M2 macrophages. A stable and accurate M2I Score for M2 macrophages used in colon adenocarcinoma was determined based on four hub genes. The M2I Score was positively correlated with the tumor mutation load (TMB). The M2I Score of the group with high instability of microsatellites was higher than that of the group with low instability of microsatellites and microsatellite-stable group. Combined with the Cancer Immunome Atlas database, we concluded that patients with high M2I Scores were more sensitive to programmed cell death protein 1 (PD-1) inhibitors and PD-1 inhibitors combined with cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) inhibitors. The low-rating group may have better efficacy without immune checkpoint inhibitors or with CTLA4 inhibitors alone. CONCLUSION: Four prognostic hub genes associated with M2 macrophages were screened to establish the M2I Score. Patients were divided into two subgroups: high M2I Score group and low M2I Score group. TMB, MSI, and sensitivity to immunotherapy were higher in the high-rated group. PD-1 inhibitors or PD-1 combined with CTLA-4 inhibitors are preferred for patients in the high-rated group who are more sensitive to immunotherapy.

Metabolomics Reveals Process of Allergic Rhinitis Patients with Single- and Double-Species Mite Subcutaneous Immunotherapy.

Allergen immunotherapy (AIT) is the only treatment that can change the course of allergic diseases. However, there has not been any research on metabolic reactions in relation to AIT with single or mixed allergens. In this study, patients with allergic rhinitis caused by Dermatophagoides pteronyssinus (Der p) and Dermatophagoides farinae (Der f) were treated with single-mite (Der p) and double-mite (Der p:Der f = 1:1) subcutaneous immunotherapy (SCIT), respectively. To compare the efficacy and the dynamic changes of inflammation-related single- and double-species mite subcutaneous immunotherapy (SM-SCIT and DM-SCIT), we performed visual analogue scale (VAS) score, rhinoconjunctivitis quality of life questionnaire (RQLQ) score and serum metabolomics in allergic rhinitis patients during SCIT. VAS and RQLQ score showed no significant difference in efficacy between the two treatments. A total of 57 metabolites were identified, among which downstream metabolites (5(S)-HETE (Hydroxyeicosatetraenoic acid), 8(S)-HETE, 11(S)-HETE, 15(S)-HETE and 11-hydro TXB2) in the ω-6-related arachidonic acid and linoleic acid pathway showed significant differences after approximately one year of treatment in SM-SCIT or DM-SCIT, and the changes of the above serum metabolic components were correlated with the magnitude of RQLQ improvement, respectively. Notably, 11(S)-HETE decreased more with SM-SCIT, and thus it could be used as a potential biomarker to distinguish the two treatment schemes. Both SM-SCIT and DM-SCIT have therapeutic effects on patients with allergic rhinitis, but there is no significant difference in efficacy between them. The reduction of inflammation-related metabolites proved the therapeutic effect, and potential biomarkers (arachidonic acid and its downstream metabolites) may distinguish the options of SCIT.

Potential Impact of ALKBH5 and YTHDF1 on Tumor Immunity in Colon Adenocarcinoma.

BACKGROUND: ALKBH5 and YTHDF1 are regarded as the eraser and reader, respectively, in N6-methyladenosine (m6A) modification. Recently, immune contexture has been drawing increasing attention in terms of the progression and treatment of cancers. This study aimed to determine the relationship between ALKBH5/YTHDF1 and immunological characteristics of colon adenocarcinoma (COAD). METHODS: Expression of ALKBH5 and YTHDF1 was investigated across TCGA and GEO validated in our study. Patients with COAD were divided into two clusters using consensus clustering based on the expression of ALKBH5 and YTHDF1. We then compared their clinical characteristics and performed gene set enrichment analysis (GSEA) to identify the functional differences. Immune infiltration analyses were conducted using ESTIMATE, CIBERSORT, and ssGSEA. In addition, we evaluated the expression of the targets of immune checkpoint inhibitors (ICIs) and calculated the tumor mutation burden (TMB) of the tumor samples. Weighted gene co-expression network analysis (WGCNA) was used to identify the genes related to both ALKBH5/YTHDF1 expression and immunity. GSE39582 was utilized for external validation of immunological features between the two clusters. RESULTS: Cluster 2 had high expression of ALKBH5 and lesser so of YTHDF1, whereas Cluster 1 had just the reverse. Cluster 1 had a higher N stage and pathological stage than Cluster 2. The latter had stronger immune infiltration, higher expression of targets of ICIs, more TMB, and a larger proportion of deficiency in mismatch repair-microsatellite instability-high (dMMR-MSI-H) status than Cluster 1. Moreover, WGCNA revealed 14 genes, including PD1 and LAG3, related to both the expression of ALKBH5/YTHDF1 and immune scores. CONCLUSIONS: ALKBH5 and YTHDF1 influence immune contexture and can potentially transform cold tumors into hot tumors in patients with COAD.

Identification and quantification of markers in Azedarach Fructus and Toosendan Fructus.

Toosendan Fructus with various pharmaceutical activities is a good source for the finding of new bioactive components, especially limonoids inside have been reported to have anticancer and antifeedant activities. To find more potential new bioactive compounds, the mass spectrometric characteristics of nimbolinin-type limonoids were first investigated. Utilizing these characteristics, totally 60 nimbolinins, including 33 new ones and at least 10 bioactive compounds, were identified by ultra-high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UHPLC-Q-TOF/MS). Furthermore, based on UHPLC-Q-TOF/MS and statistical analysis, 9 limonoids were identified to be the differential components between Toosendan Fructus and Azedarach Fructus. Particularly, nimbolinin A and toosendanin (TSN) with higher content in Azedarach Fructus and Toosendan Fructus respectively should be good markers. Finally, an UHPLC-triple quadrupole mass spectrometry (UHPLC-QQQ/MS) quantification approach for nimbolinin A and TSN was developed for their quality control. These results provided the basis for drug development and quality control of Toosendan Fructus and Azedarach Fructus.

Qualitative and quantitative analysis of lipo-alkaloids and fatty acids in Aconitum carmichaelii using LC-MS and GC-MS.

INTRODUCTION: Lipo-alkaloid (LA) is a kind of C19 -norditerpenoid alkaloid in Aconitum species, which usually contains an aconitane skeleton and one or two fatty acid residues. OBJECTIVE: To qualify and quantify the fatty acids and lipo-alkaloids in Aconitum carmichaelii. METHODOLOGY: An ultra-high performance liquid chromatography-triple quadrupole-mass spectrometry (UHPLC-QQQ-MS) method was established to quantify LAs, while the free fatty acids were identified by gas chromatography-mass spectrometry (GC-MS) and ultra-high performance liquid chromatography-quadrupole-time-of-flight-mass spectrometry (UHPLC-Q-TOF-MS). RESULTS: Six major LAs (1-6) containing linoleic, palmitic, and oleic acid residues as side chains were quantified. Eighteen fatty acids were determined by GC-MS, and 15 were detected as the side chains of LAs. The LAs containing these 15 fatty acid residues accounted for about a third of the total identified LAs. Moreover, the contents of linoleic, palmitic, and oleic acids were highest. In addition, 12 oxygenated fatty acids were also identified by UHPLC-Q-TOF-MS for the first time. CONCLUSION: The positive correlation between free fatty acids and LAs in A. carmichaelii indicated that the types and contents of LAs were influenced by free fatty acids.

Identification of Oxygenated Fatty Acid as a Side Chain of Lipo-Alkaloids in Aconitum carmichaelii by UHPLC-Q-TOF-MS and a Database.

Lipo-alkaloid is a kind of C19-norditerpenoid alkaloid usually found in Aconitum species. Structurally, they contain an aconitane skeleton and one or two fatty acid moieties of 3-25 carbon chains with 1-6 unsaturated degrees. Analysis of the lipo-alkaloids in roots of Aconitum carmichaelii resulted in the isolation of six known pure lipo-alkaloids (A1-A6) and a lipo-alkaloid mixture (A7). The mixture shared the same aconitane skeleton of 14-benzoylmesaconine, but their side chains were determined to be 9-hydroxy-octadecadienoic acid, 13-hydroxy-octadecadienoic acid and 10-hydroxy-octadecadienoic acid, respectively, by MS/MS analysis after alkaline hydrolysis. To our knowledge, this is the first time of the reporting of the oxygenated fatty acids as the side chains in naturally-occurring lipo-alkaloids. In order to identify more lipo-alkaloids, a compound database was established based on various combinations between the aconitane skeleton and the fatty acid chain, and then, the identification of lipo-alkaloids was conducted using the database, UHPLC-Q-TOF-MS and MS/MS. Finally, 148 lipo-alkaloids were identified from A. carmichaelii after intensive MS/MS analysis, including 93 potential new compounds and 38 compounds with oxygenated fatty acid moieties.