Targeted metabolomics reveals the aberrant energy status in diabetic peripheral neuropathy and the neuroprotective mechanism of traditional Chinese medicine JinMaiTong

Diabetic peripheral neuropathy (DPN) is a common and devastating complication of diabetes, for which effective therapies are currently lacking. Disturbed energy status plays a crucial role in DPN pathogenesis. However, the integrated profile of energy metabolism, especially the central carbohydrate metabolism, remains unclear in DPN. Here, we developed a metabolomics approach by targeting 56 metabolites using high-performance ion chromatography-tandem mass spectrometry (HPIC-MS/MS) to illustrate the integrative characteristics of central carbohydrate metabolism in patients with DPN and streptozotocin-induced DPN rats. Furthermore, JinMaiTong (JMT), a traditional Chinese medicine (TCM) formula, was found to be effective for DPN, improving the peripheral neurological function and alleviating the neuropathology of DPN rats even after demyelination and axonal degeneration. JMT ameliorated DPN by regulating the aberrant energy balance and mitochondrial functions, including excessive glycolysis restoration, tricarboxylic acid cycle improvement, and increased adenosine triphosphate (ATP) generation. Bioenergetic profile was aberrant in cultured rat Schwann cells under high-glucose conditions, which was remarkably corrected by JMT treatment. In-vivo and in-vitro studies revealed that these effects of JMT were mainly attributed to the activation of adenosine monophosphate (AMP)-activated protein kinase (AMPK) and downstream peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α). Our results expand the therapeutic framework for DPN and suggest the integrative modulation of energy metabolism using TCMs, such as JMT, as an effective strategy for its treatment.

Targeted metabolomics study of fatty-acid metabolism in lean metabolic-associated fatty liver disease patients

BACKGROUND The annual incidence of metabolic-associated fatty liver disease(MAFLD)in China has been increasing and is often overlooked owing to its insidious charac-teristics.Approximately 50%of the patients have a normal weight or are not obese.They are said to have lean-type MAFLD,and few studies of such patients are available.Because MAFLD is associated with abnormal lipid metabolism,lipid-targeted metabolomics was used in this study to provide experimental evidence for early diagnosis and pathogenesis.MAFLD and analyze metabolic pathways.UPLC-Q-Orbitrap/MS content determination was used to determine serum palmitic acid(PA),oleic acid(OA),linoleic acid(LA),and arachidonic acid(AA)levels in lean-type MAFLD patients.RESULTS Urea nitrogen and uric acid levels were higher in lean-type MAFLD patients than in healthy individuals(P<0.05).Alanine transaminase and cholinesterase levels were higher in lean-type MAFLD patients than in healthy indi-viduals(P<0.01).The expression of high-density lipoprotein and apolipoprotein A-1 were lower in lean-type MAFLD patients than in healthy individuals(P<0.05)and the expression of triglycerides and fasting blood glucose were increased(P<0.01).A total of 65 biomarkers that affected the synthesis and metabolism of fatty acids were found with P<0.05 and variable importance in projection>1.The levels of PA,OA,LA,and AA were significantly increased compared with healthy individuals.CONCLUSION The metabolic profiles of lean-type MAFLD patients and healthy participants differed significantly,yielding 65 identified biomarkers.PA,OA,LA,and AA exhibited the most significant changes,offering valuable clinical guidance for prevention and treatment of lean-type MAFLD.

Untargeted metabolomics analysis of four date palm(Phoenix dactylifera L.)cultivars using MS and NMR

Since ancient times,the inhabitants of dry areas have depended on the date palm(Phoenix dactylifera L.)as a staple food and means of economic security.For example,dates have been a staple diet for the inhabitants of the Arabian Peninsula and Sahara Desert in North Africa for millennia and the local culture is rich in knowledge and experience with the benefits of dates,suggesting that dates contain many substances essential for the human body.Madinah dates are considered one of the most important types of dates in the Arabian Peninsula,with Ajwa being one of the most famous types and grown only in Madinah,Saudi Arabia.Date seeds are traditionally used for animal feed,seed oil production,cosmetics,and as a coffee substitute.Phytochemical compounds that have been detected in date fruits and date seeds include phenolic acids,carotenoids,and flavonoids.Phenolic acids are the most prevalent bioactive constituents that contribute to the antioxidant activity of date fruits.The bioactive properties of these phytochemicals are believed to promote human health by reducing the risk of diseases such as chronic inflammation.Ajwa dates especially are thought to have superior bioactivity properties.To investigate these claims,in this study,we compare the metabolic profiles of Ajwa with different types of dates collected from Saudi Arabia and Tunisia.We show by UHPLC-MS that date seeds contain several classes of flavonoids,phenolic acids,and amino acid derivatives,including citric acid,malic acid,lactic acid,and hydroxyadipic acid.Additionally,GC-MS profiling showed that date seeds are richer in metabolite classes,such as hydrocinnamic acids(caffeic,ferulic and sinapic acids),than flesh samples.Deglet N fruit extract(minimum inhibitory concentration:27 MIC/μM)and Sukkari fruit extract(IC_(50):479±0.58μg/mL)have higher levels of antibacterial and antioxidative activity than Ajwa fruits.However,the seed analysis showed that seed extracts have better bioactivity effects than fruit extracts.Specifically,Ajwa extract showed the best MIC and strongest ABTS radical-scavenging activity among examined seed extracts(minimum inhibitory concentration:20μM;IC_(50):54±3.61μg/mL).Our assays are a starting point for more advanced in vitro antibacterial models and investigation into the specific molecules that are responsible for the antioxidative and anti-bacterial activities of dates.

Mechanism of Xingnaojing injection intervention in cerebral ischemiareperfusion rat model based on GC-MS metabolomics

Objective:To investigate the protective effect of Xingnaojing injection on cerebral ischemia-reperfusion in rats and its metabolic pathway and mechanism.Methods:The cerebral ischemia reperfusion model of rats was established by suture occlusion.After successful model evaluation,he rats were randomly divided into model group and Xingnaojing group with eight rats in each group.In the sham operation group,only blood vessel separation was performed without embolization.Xingnaojing group was given intraperitoneal injection,model group and sham operation group were given the same dose of normal saline,twice a day.Three days later,HE staining and GC-MS metabolomics were used to detect the changes of endogenous metabolites in the rat brain tissue.Principal component analysis(PCA)and orthogonal partial least squares discriminant analysis(OPLS-DA)were used to screen out differential metabolites and analyze their metabolic pathways.Results:Endogenous metabolites were disturbed after cerebral ischemia-reperfusion injury in rats.Seventy-one different metabolites were screened from the model group and the sham group,of which three were down-regulated and sixty-eight were up-regulated.Eighty-eight different metabolites were found between Xingnaojing group and sham operation group,among which eight were down-regulated and eighty up-regulated.After screening of Xingnaojing group and model group,twelve different metabolites were obtained,among which seven were down-regulated and five up-regulated.By analyzing the differences of metabolites,Xingnaojing injection was considered to be involved in the metabolic pathway after cerebral ischemia-reperfusion in rats,including amino acid metabolism(beta alanine metabolism,alanine,glutamic acid and aspartic acid metabolism,histidine metabolism,arginine and proline metabolism),glutathione metabolism,pyrimidine metabolism,ABC transporter,nitrogen metabolism and other metabolic pathways.Conclusion:Xingnaojing injection can restore the levels of metabolites in cerebral ischemia-reperfusion rats in certain degrees,mainly through amino acid metabolism,ABC transporter,glutathione metabolism and other metabolic pathways to regulate cerebral ischemia-reperfusion injury in rats.

Plasma metabolomics study of Buyang Huanwu Decoction improving learning andmemory in D-gal model mice based on GC-MS

Objective:To study the protective effect of Buyang Huanwu Decoction on the learning and memory ability of D-gal induced aging mice using GC-MS metabolomics method.Methods:Twenty-four three-month-old kunming animals were selected as experimental samples and randomly divided into control group,model group and Buyang Huanwu Decoction according to their body weight.The memory level of experimental animals was detected by novel body recognition test,and the neuron structure of experimental animals was detected by HE staining.The plasma of each group of experimental animals was quantitatively analyzed by gas chromatography-mass spectrometry,and the important metabolites and main metabolic pathways in the process of pathological changes were traced by using plasma metabolism.Results:In HE staining,compared with blank group,hippocampal neurons in model group were disordered and morphologically abnormal.Compared with the model group,the hippocampal neurons in Buyang Huanwu Decoction group arranged regularly and had normal morphology.Compared with blank group,the index of new object recognition in model group was significantly decreased(P<0.05);Compared with model group,the new object recognition index of Buyang Huanwu Decoction group was significantly increased(P<0.05).Five different metabolites of AD were identified by GC-MS,which were L-pyroglutamate,lysine,pyrophosphoric acid,creatinine andα-lactose.Conclusion:Buyang Huanwu Decoction has a significant effect on D-gal model mice,and can effectively improve their learning and memory level.The mechanism may be related to glutathione metabolism and aminophyl biosynthesis.

HS-SPME-GC-MS/MS结合非靶向代谢组学分析涪陵榨菜发酵过程中挥发性成分

为探究涪陵榨菜在“三腌三榨”加工过程中挥发性成分的差异情况,通过非靶向代谢组学结合气相色谱-串联质谱技术与多元统计学方法,分析并探讨了涪陵榨菜在自发酵过程中挥发性代谢物的变化及其显著差异代谢途径。结果表明,不同腌制阶段榨菜中共检测到627种挥发性成分,主要包括烃类、酯类、杂环化合物、萜类、醛类、酮类、醇类、芳烃、酚类、胺类、含硫化合物、酸类、卤代烃、含氮化合物等。不同腌制阶段榨菜中差异显著挥发性成分存在较大差异,一腌阶段与对照组的特有差异挥发性成分为157个,二腌与一腌阶段组的特有差异挥发性成分为28个,三腌与二腌阶段组的特有差异挥发性成分为1个。经京都基因与基因组百科全书通路分析,差异挥发性成分显著富集的代谢通路包括次生代谢产物的生物合成、二萜类生物合成、单萜类生物合成、咖啡因代谢、脂肪酸生物合成等。本研究从代谢组学的角度分析了发酵榨菜的特异代谢产物,可为涪陵榨菜的标准化生产提供理论依据。

基于GC-MS分析两地白色藜麦种子的代谢差异

为了探究四川盐源县和青海都兰县白色藜麦种子的代谢物质差异,对其进行非靶向代谢组学的分析。利用GC-MS技术以及多元统计分析对两地的白色藜麦种子进行比较,发现两地的藜麦种子代谢物质有差异,共检测到29个显著差异物质,主要包括15个氨基酸、6个有机酸和一些糖醇、胺类、多酚、生物碱。其中有22个代谢物质表达上调,7个表达下调,在上调表达代谢物中有12个氨基酸(甘氨酸、L-缬氨酸、谷胱甘肽、GABA等)和5个有机酸(乳清酸、肉桂酸、2-氧戊二酸等)。通过MetaboAnalyst进行通路分析,发现有24条代谢通路与上调表达代谢物相关,其中有7条通路影响较显著,分别为谷胱甘肽代谢,氮代谢,丙氨酸、天冬氨酸和谷氨酸代谢,氨酰基-tRNA生物合成,苯基丙氨酸代谢,硫代谢,甘氨酸、丝氨酸和苏氨酸代谢。谷胱甘肽代谢途径的影响最为显著,而此途径与植物的抗逆性密切相关,其中检测到的代谢物主要有甘氨酸和谷胱甘肽在四川盐源的藜麦中有更高的表达水平,表明四川盐源的白色藜麦较青海都兰的白色藜麦有更强的抗氧化能力,使得植物有较好的抗逆性能在逆境中生存,这为指导两地白色藜麦的栽培育种和抗逆性机理的研究提供了理论依据。

Metabolomics Profile of Potato Tubers after Phosphite Treatment

Phosphite (Phi)-based fungicides are used to control the oomycete Phytophthora infestans which causes late blight disease, the most devastating disease in potatoes. In order to examine the effects of Phi-based fungicides on potato tubers through foliar or post-harvest application, a metabolite profiling approach based on gas chromatography coupled to mass spectrometry (GC-MS) has been established. A total of 132 metabolites were detected using the GC-MS approach. Among these, 34 metabolites were identified after normalization and annotated with a compound name with standard mass spectral library. Metabolomic analysis of Phi-treated plants showed significant differences in the levels of many metabolites especially amino acids. Multivariate statistical approaches, such as principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA), were employed to explore the relationships between metabolites to detect group differences. A good discrimination between the control and the Phi-treated plants was observed, which demonstrated that significant changes in the metabolite profile have been caused by the two different Phi applications (foliar or post-harvest). This finding suggests that the alteration of specific metabolite levels by accumulation of Phi can lead to resistance against the pathogen.

Discovering metabolic vulnerability using spatially resolved metabolomics for antitumor small molecule-drug conjugates development as a precise cancer therapy strategy

Against tumor-dependent metabolic vulnerability is an attractive strategy for tumor-targeted therapy.However,metabolic inhibitors are limited by the drug resistance of cancerous cells due to their metabolic plasticity and heterogeneity.Herein,choline metabolism was discovered by spatially resolved metabolomics analysis as metabolic vulnerability which is highly active in different cancer types,and a choline-modified strategy for small molecule-drug conjugates(SMDCs)design was developed to fool tumor cells into indiscriminately taking in choline-modified chemotherapy drugs for targeted cancer therapy,instead of directly inhibiting choline metabolism.As a proof-of-concept,choline-modified SMDCs were designed,screened,and investigated for their druggability in vitro and in vivo.This strategy improved tumor targeting,preserved tumor inhibition and reduced toxicity of paclitaxel,through targeted drug delivery to tumor by highly expressed choline transporters,and site-specific release by carboxylesterase.This study expands the strategy of targeting metabolic vulnerability and provides new ideas of developing SMDCs for precise cancer therapy.

Targeted metabolomics of sulfated bile acids in urine for the diagnosis and grading of intrahepatic cholestasis of pregnancy

Intrahepatic cholestasis of pregnancy(ICP)is related to cholestatic disorder in pregnancy.Total urinary sulfated bile acids(SBAs)were found increased in ICP.We distinguished the metabolic profiling of urinary SBAs in ICP to find potential biomarkers for the diagnosis and grading of ICP.The targeted metabolomics based on high-performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)was used to analyze urinary SBAs profiling in mild and severe ICP cases,as well as healthy controls.16 kinds of urinary SBAs were determined by HPLC-MS/MS.Sulfated dihydroxy glycine bile acid(di-GBA-S),glycine cholic acid 3-sulfate(GCA-3S),sulfated dihydroxy taurine bile acid(di-TBA-S)and taurine cholic acid 3-sulfate(TCA-3S)increased significantly in ICP group compared with the control group.Seven kinds of SBAs were significantly different(p<0.05)between the ICP group and the control group,with the variable importance in the projection(VIP)value more than one by the orthogonal partial least squares discriminant analysis(OPLS-DA).GCA-3S was well-suited to be used as the biomarker for the diagnosis of ICP with the sensitivity of 100%and specificity of 95.5%.A multi-variable logistic regression containing GCA-3S and di-GBA-S-1 was constructed to distinguish severe ICP from mild ICP,with the sensitivity of 94.4%and specificity of 100%.The developed HPLC-MS/MS method is suitable for the measurement of urinary SBAs profiling.Moreover,the urinary SBAs in the metabolomic profiling have the potential to be used as non-intrusive biomarkers for the diagnosis and grading of ICP.

Comparative analysis of volatile oils in the stems and roots of Ephedra sinica via GC-MS-based plant metabolomics

With a great difference in therapeutic effects of Mahuang(MH, the stems of Ephedra sinica) and Mahuanggen(MHG, the roots of Ephedra sinica), chemical differences between MH and MHG should be investigated. In the present study, gas chromatography-mass spectrometry(GC-MS)-based plant metabolomics was employed to compare volatile oil profiles of MH and MHG. The antioxidant activities of volatile oils from MH and MHG were also compared. 32 differential chemical markers were identified according to the variable importance in the projection(VIP) value of orthogonal partial least squares discriminant analysis(OPLS-DA) and P value of Mann-Whitney test. Among them, chemical markers of tetramethylpyrazine(TMP) and α-terpineol were quantified. Their contents were much higher in most MH samples compared with MHG. The antioxidant assay demonstrated that MH had significantly higher free radical-scavenging activity than MHG. Although MH and MHG derived from the same medicinal plant, there was much difference in their volatile oil profiles. MH samples had significantly higher content of two reported pharmacologically important chemical markers of TMP and α-terpineol, which may account for their different antioxidant activities.

A Clinical and Animal Experiment Integrated Platform for Small-Molecule Screening Reveals Potential Targets of Bioactive Compounds from a Herbal Prescription Based on the Therapeutic Efficacy of Yinchenhao Tang for Jaundice Syndrome

A herbal prescription in traditional Chinese medicine(TCM)has great complexity,with multiple components and multiple targets,making it extremely challenging to determine its bioactive compounds.Yinchenhao Tang(YCHT)has been extensively used for the treatment of jaundice disease.Although many studies have examined the efficacy and active ingredients of YCHT,there is still a lack of an in-depth systematic analysis of its effective components,mechanisms,and potential targets—especially one based on clinical patients.This study established an innovative strategy for discovering the potential targets and active compounds of YCHT based on an integrated clinical and animal experiment platform.The serum metabolic profiles and constituents of YCHT in vivo were determined by ultra-performance liquid chromatography–quadrupole time-of-flight mass spectrometry(UPLC-Q-ToF-MS)-based metabolomics combined with a serum pharmacochemistry method.Moreover,a compound–target–pathway network was constructed and analyzed by network pharmacology and ingenuity pathway analysis(IPA).We found that eight active components could modulate five key targets.These key targets were further verified by enzyme-linked immunosorbent assay(ELISA),which indicated that YCHT exerts therapeutic effects by targeting cholesterol 7a-hydroxylase(CYP7A1),multidrug-resistance-associated protein 2(ABCC2),multidrug-resistance-associated protein 3(ABCC3),uridine diphosphate glucuronosyl transferase 1A1(UGT1A1),and farnesoid X receptor(FXR),and by regulating metabolic pathways including primary bile acid biosynthesis,porphyrin and chlorophyll metabolism,and biliary secretion.Eight main effective compounds were discovered and correlated with the key targets and pathways.In this way,we demonstrate that this integrated strategy can be successfully applied for the effective discovery of the active compounds and therapeutic targets of an herbal prescription.

Effects of antibiotic antitumor drugs on nucleotide levels in cultured tumor cells:an exploratory method to distinguish the mechanisms of antitumor drug action based on targeted metabolomics

Nucleotide pools in mammalian cells change due to the influence of antitumor drugs,which may help in evaluating the drug effect and understanding the mechanism of drug action.In this study,an ion-pair RP-HPLC method was used for a simple,sensitive and simultaneous determination of the levels of 12 nucleotides in mammalian cells treated with antibiotic antitumor drugs(daunorubicin,epirubicin and dactinomycin D).Through the use of this targeted metabolomics approach to find potential biomarkers,UTP and ATP were verified to be the most appropriate biomarkers.Moreover,a holistic statistical approach was put forward to develop a model which could distinguish 4 categories of drugs with different mechanisms of action.This model can be further validated by evaluating drugs with different mechanismsof action.This targeted metabolomics study may provide a novel approach to predict the mechanism of action of antitumor drugs.

Novel biomarkers identifying hypertrophic cardiomyopathy and its obstructive variant based on targeted amino acid metabolomics

Background:Hypertrophic cardiomyopathy(HCM)is an underdiagnosed genetic heart disease worldwide.The management and prognosis of obstructive HCM(HOCM)and non-obstructive HCM(HNCM)are quite different,but it also remains challenging to discriminate these two subtypes.HCM is characterized by dysmetabolism,and myocardial amino acid(AA)metabolism is robustly changed.The present study aimed to delineate plasma AA and derivatives profiles,and identify potential biomarkers for HCM.Methods:Plasma samples from 166 participants,including 57 cases of HOCM,52 cases of HNCM,and 57 normal controls(NCs),who first visited the International Cooperation Center for HCM,Xijing Hospital between December 2019 and September 2020,were collected and analyzed by high-performance liquid chromatography-mass spectrometry based on targeted AA metabolomics.Three separate classification algorithms,including random forest,support vector machine,and logistic regression,were applied for the identification of specific AA and derivatives compositions for HCM and the development of screening models to discriminate HCM from NC as well as HOCM from HNCM.Results:The univariate analysis showed that the serine,glycine,proline,citrulline,glutamine,cystine,creatinine,cysteine,choline,and aminoadipic acid levels in the HCM group were significantly different from those in the NC group.Four AAs and derivatives(Panel A;proline,glycine,cysteine,and choline)were screened out by multiple feature selection algorithms for discriminating HCM patients from NCs.The receiver operating characteristic(ROC)analysis in Panel A yielded an area under the ROC curve(AUC)of 0.83(0.75-0.91)in the training set and 0.79(0.65-0.94)in the validation set.Moreover,among 10 AAs and derivatives(arginine,phenylalanine,tyrosine,proline,alanine,asparagine,creatine,tryptophan,ornithine,and choline)with statistical significance between HOCM and HNCM,3 AAs(Panel B;arginine,proline,and ornithine)were selected to differentiate the two subgroups.The AUC values in the training and validation sets for Panel B were 0.83(0.74-0.93)and 0.82(0.66-0.98),respectively.Conclusions:The plasma AA and derivatives profiles were distinct between the HCM and NC groups.Based on the differential profiles,the two established screening models have potential value in assisting HCM screening and identifying whether it is obstructive.

基于靶向代谢组学研究苍术麸炒前后干预脾虚大鼠氨基酸水平变化的影响

目的研究采用靶向代谢组学方法,观察苍术麸炒前后对脾虚大鼠血清氨基酸水平的变化,探讨苍术炮制机制。方法72只大鼠随机分成正常组、模型组、低剂量生苍术组(生低组)、中剂量生苍术组(生中组)、高剂量生苍术组(生高组)、低剂量麸炒苍术组(麸炒低组)、中剂量麸炒苍术组(麸炒中组)和高剂量麸炒苍术组(麸炒高组),共8组,每组9只。除正常组外,模型组通过过度疲劳、苦寒泻下和饮食不节法造模。对各组大鼠采用酶联免疫吸附测定(Enzyme Linked Immunosorbent Assay,ELISA)方法测定颌下腺中水通道蛋白3(Aquaporin-3,AQP-3)、水通道蛋白4(AQP-4)、水通道蛋白5(AQP-5)、水通道蛋白8(AQP-8)的含量,结肠中水通道蛋白1(AQP-1)、水通道蛋白2(AQP-2)、水通道蛋白9(AQP-9)、紧密连接蛋白1(zonula occludes protein-1,ZO-1)的含量。对生中组和麸炒中组采用超高效液相色谱-三重四极杆质谱(Ultra high performance liquid chromatography-triple quadrupole tandem mass spectrometry,UH-PLC-MS/MS)检测血清中24种氨基酸水平的变化。结果与正常组比较,模型组中颌下腺AQP-3、AQP-4、AQP-5、AQP-8的含量显著降低(P<0.05);模型组中结肠AQP-1和AQP-2的含量显著升高(P<0.05),AQP-9和ZO-1的含量显著降低(P<0.05)。生苍术和麸炒苍术对上述指标均有调节作用。经进一步同等剂量的生苍术和麸炒苍术相比,麸炒中组使上述指标含量升高更明显。与正常组比较,模型组血清中L-缬氨酸等4种物质的水平显著升高(P<0.05),L-酪氨酸等11种物质的水平均显著降低(P<0.05)。经进一步比较,麸炒苍术对上述指标调节效果优于生苍术。靶向代谢通路分析表明,这些差异代谢物主要与精氨酸和脯氨酸代谢、氨酰tRNA生物合成、甘氨酸、丝氨酸和苏氨酸代谢、乙醛酸和二羧酸代谢通路有关。结论苍术炮制后的增效机制可能与对脾虚大鼠血清中氨基酸调节有关。

桑葚发酵前后酚类组成变化及其抗氧化活性分析

目的:旨在分析桑葚饮料发酵前后酚类物质的组成变化和抗氧化功能差异。方法:利用毕赤酵母菌(Pichia kudriavzevii)和融合魏斯氏乳酸菌(Weissella confusa)通过二次发酵桑葚制备桑葚饮料,比较桑葚发酵前后酚类物质对DPPH、OH、ABTS+自由基的清除能力及还原力,并通过非靶向代谢组学技术对不同组别样品差异代谢物进行鉴定,进而探究发酵前后酚类物质组成变化与抗氧化性能之间的相关性。结果:发酵后桑葚酚类物质(1 mg/mL)对DPPH自由基清除率由发酵前的45.97%±2.23%提高到59.01%±3.59%(P<0.05);对OH自由基清除率由发酵前的68.68%±1.23%提高到78.55%±0.57%(P<0.05);发酵后的桑葚饮料中酚类物质的还原力显著提高(P<0.05);发酵前后的酚类化合物对ABTS+自由基清除能力无显著差异(P>0.05)。从发酵前后桑葚酚类物质中共筛选出46种差异代谢物,包括3种花色苷类、10种酚酸类、18种类黄酮及15种其它酚类物质,其中发酵后上调和下调的代谢物分别为26种和20种,共涉及4个相关代谢通路,包括植物次生代谢产物的生物合成、苯丙烷类生物合成、类黄酮生物合成和花色苷生物合成。58.70%的酚类物质与DPPH和OH自由基清除率呈正相关。结论:桑葚经发酵后酚类物质组成变化及含量的增加使得抗氧化能力得到明显上调。

柔嫩艾美耳球虫感染鸡盲肠内容物非靶向代谢组学分析

【目的】基于非靶向代谢组学探究感染柔嫩艾美耳球虫(Eimeria tenella)后鸡盲肠内容物中代谢物的变化差异,为识别和鉴定鸡球虫病潜在的生物标志物及治疗靶点提供参考依据。【方法】将60羽健康罗曼粉鸡随机分为正常组和模型组,每组30羽,模型组经口灌服柔嫩艾美耳球虫孢子化卵囊(1×104个/羽),正常组经口灌服等体积生理盐水,连续灌服5 d,然后解剖试验鸡,无菌采集鸡盲肠内容物,基于非靶向代谢组学分析正常组和模型组鸡盲肠内容物,筛选出显著差异代谢物进行KEEG代谢通路富集分析。【结果】从模型组与正常组的鸡盲肠内容物中共筛选到253种显著差异代谢物,其中,上调表达的显著差异代谢物有184种,包含L-酪氨酸、L-蛋氨酸、L-谷氨酰胺、牛磺酸、花生四烯酸、二十二碳六烯酸乙酯、胆碱和磷酸胆碱等;下调表达的显著差异代谢物有69种,包括脱氧腺苷、L-缬氨酸、N-(5-氨基戊基)乙酰胺和N-乙酰-L-谷氨酸等。正离子模式下,主要有牛磺酸、磷酸胆碱、甜菜碱、L-亮氨酸、L-谷氨酰胺、胆碱、神经鞘氨醇和L-色氨酸等20种代谢物上调表达;负离子模式下,主要有花生四烯酸、牛磺酸、L-苯丙氨酸、L-亮氨酸、琥珀酸、黄嘌呤、尿嘧啶和L-谷氨酰胺等20种代谢物上调表达。鸡盲肠内容物显著差异代谢物主要被富集到ABC转运蛋白、氨酰tRNA生物合成、赖氨酸降解、嘧啶代谢、嘌呤代谢、不饱和脂肪酸生物合成等20条KEEG代谢通路上。【结论】柔嫩艾美耳球虫感染后鸡盲肠代谢物发生显著变化,主要影响ABC转运蛋白、氨酰tRNA生物合成、氨基酸代谢、嘧啶代谢和嘌呤代谢等代谢通路。因此,牛磺酸、磷酸胆碱、L-谷氨酰胺、花生四烯酸等显著差异代谢物可作为潜在的生物标志物,用于鸡球虫病诊断检测。

鳜鱼宰后冷藏24 h内肌肉代谢物及相关风味的变化

为探究鲜活鳜鱼宰后4℃冷藏24 h过程中肌肉代谢物变化情况,借助超高效液相色谱-高分辨质谱技术,结合非靶向代谢组学方法对宰后鳜鱼在不同冷藏条件(4℃,0、2、4、6、9、12、24 h)的差异代谢物进行多元统计分析、代谢通路分析及相关风味计算。结果表明:鳜鱼宰后冷藏24 h过程中共有33种代谢物被鉴定为差异代谢物,包括3种有机酸及衍生物(氨基酸、有机酸)、8种有机杂环化合物(嘌呤和嘌呤衍生物、内酯等)、7种核苷、核苷酸及其类似物(嘌呤核苷及核苷酸、嘧啶核苷酸)、9种有机氧化合物(碳水化合物及其结合物、少量醇类)、4种脂质和类脂分子(脂肪醇、脂肪酸酯等)、1种黄酮苷、1种生物碱及其衍生物;根据差异代谢物和代谢通路拓扑分析和京都基因与基因组百科全书分析,得到9种关键差异代谢物,分别为琥珀酸、天冬氨酸、5’-腺苷酸(5’-adenosine monophosphate,AMP)、次黄嘌呤核苷、一磷酸腺苷琥珀酸、黄嘌呤、5’-鸟苷酸(5’-guanosine monophosphate,GMP)、核糖-5-磷酸和次黄嘌呤;关键差异代谢产物参与的代谢通路主要为嘌呤代谢,其次是天冬氨酸、谷氨酸代谢和三羧酸循环;提出相对滋味活度值和相对味精当量计算方法,根据计算结果发现,鲜鳜鱼的滋味主要由天冬氨酸等鲜味氨基酸与AMP和GMP协同产生,冷藏2~6 h,滋味的主要贡献物质是AMP和GMP,而冷藏9~24 h则主要是GMP的呈味作用;单从冷藏24 h的角度来看,宰后鲜鳜鱼的滋味最好,冷藏后由于天冬氨酸含量下降导致鲜味损失,冷藏9~24 h GMP的积累使鳜鱼鲜味再次增加。

基于非靶向代谢组学分析不同包装方式预制烤鱼代谢物的差异

为探究不同包装预制烤鱼的代谢物差异,采用液相色谱-串联质谱技术,基于非靶向代谢组学方法分析比较托盒包装、真空包装和气调包装预制烤鱼的代谢物组成。结果表明,在二级质谱信息下,3种包装的预制烤鱼共鉴定出318种代谢物。依据正交偏最小二乘法判别分析模型的变量重要性投影值(variable importance projection value,VIP,VIP>1)和P<0.05,共筛选出47种差异代谢物,包括脂肪酸类10种,核苷酸类10种,氨基酸类9种,有机酸及衍生物类7种,苯及衍生物类3种,醇胺类2种,其他类6种。通过对47种差异代谢物相对含量的聚类热图分析,发现3种不同包装方式预制烤鱼的代谢物相对含量存在差异。其中,气调包装烤鱼的多种呈味氨基酸和单磷酸腺苷相对含量明显高于常规的真空和托盒包装。研究结果初步表明,气调包装对保持烤鱼鲜味有积极作用,将为烤鱼包装多样化发展提供方向。

贵州红托竹荪和冬荪的品质评价

为分析贵州红托竹荪和冬荪的品质差异,本研究采用营养成分精准定量方法分析了红托竹荪和冬荪的34种营养成分,并基于超高效液相色谱-四极杆飞行时间质谱的非靶向代谢组学技术比较了红托竹荪和冬荪的差异代谢物。结果表明,红托竹荪中L-麦角硫因、麦角甾醇、总膳食纤维、铁含量较高,其蛋白中必需氨基酸含量(342.2 mg/g)更接近联合国粮食及农业组织/世界卫生组织模式值;冬荪中可溶性糖、钙、蛋白质含量较高,其中检出的海藻糖、甘露醇、甘露糖、葡萄糖的总含量(450.8 mg/g)远高于红托竹荪(114.7 mg/g)。利用多元统计分析,从红托竹荪和冬荪代谢物中筛选出388个差异代谢物,主要包括脂质类化合物145个、氨基酸类化合物38个、糖类化合物17个。与红托竹荪相比,冬荪中有126个代谢物下调,262个代谢物上调,主要的差异代谢物是风味前体物质或风味物质,与红托竹荪和冬荪的风味密切相关。本研究较为系统地评价了红托竹荪和冬荪中营养成分和代谢物差异,可为红托竹荪和冬荪的品质分析及功能成分挖掘提供数据基础。