Changes in the Non-targeted Metabolomic Profile of Three-year-old Toddlers with Elevated Exposure to Polycyclic Aromatic Hydrocarbons

Objective To investigate changes in the urinary metabolite profiles of children exposed to polycyclic aromatic hydrocarbons(PAHs)during critical brain development and explore their potential link with the intestinal microbiota.Methods Liquid chromatography-tandem mass spectrometry was used to determine ten hydroxyl metabolites of PAHs(OH-PAHs)in 36-month-old children.Subsequently,37 children were categorized into low-and high-exposure groups based on the sum of the ten OH-PAHs.Ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry was used to identify non-targeted metabolites in the urine samples.Furthermore,fecal flora abundance was assessed by 16S rRNA gene sequencing using Illumina MiSeq.Results The concentrations of 21 metabolites were significantly higher in the high exposure group than in the low exposure group(variable importance for projection>1,P<0.05).Most of these metabolites were positively correlated with the hydroxyl metabolites of naphthalene,fluorine,and phenanthrene(r=0.336–0.531).The identified differential metabolites primarily belonged to pathways associated with inflammation or proinflammatory states,including amino acid,lipid,and nucleotide metabolism.Additionally,these distinct metabolites were significantly associated with specific intestinal flora abundances(r=0.34–0.55),which were mainly involved in neurodevelopment.Conclusion Higher PAH exposure in young children affected metabolic homeostasis,particularly that of certain gut microbiota-derived metabolites.Further investigation is needed to explore the potential influence of PAHs on the gut microbiota and their possible association with neurodevelopmental outcomes.

Identification of key taste components in Baccaurea ramiflora Lour.fruit using non-targeted metabolomics

Among the numerous fruit species of Baccaurea ramiflora Lour.,‘LR’(white flesh)and‘BR’(pink flesh)are two kinds of local strains with high edibility.In order to study the metabolic causes of taste differences,we performed the non-targeted metabonomics analysis of‘LR’and‘BR’using LC-MS/MS.541 metabolites were totally identified,and 45 kinds of metabolites(carbohydrates,fatty acids,flavonoids and terpenoids,etc.)were different between the two strains.The results indicate L-sorbose,D-(+)-glucose,citric acid,L-phenylalanine and oleamide,α-eleostearic acid were the main primary metabolites.The significant difference existed in pathways of unsaturated fatty acids between the studied two strains by pathway enrichment analysis.The results demonstrate that the different in composition,as well as the abundance of primary and secondary metabolites may be the potential causes of taste differences,which provides a new insight into the possible metabolic factors setting off the changing taste of B.ramiflora.

Non-target lung embolization during portal vein embolization due to an unrecognized portosystemic venous fistula:A case report

BACKGROUND Portal vein embolization(PVE)is an effective and relatively safe procedure performed prior to major hepatic resection to enhance future liver remnant.Nontarget embolization during PVE is rare,and if it occurs,it usually affects the future liver remnant.Intrahepatic portosystemic venous fistulas are extremely rare in non-cirrhotic livers.We report a case of non-targeted lung embolization during PVE due to an unrecognized intrahepatic portosystemic fistula.CASE SUMMARY A 60-year-old male presented with metastatic colon cancer of the liver.The patient underwent preoperative right PVE.During the embolization procedure,a small amount of glue and lipiodol emulsion was embolized to the heart and lungs through an unrecognized intrahepatic portosystemic fistula.The patient remained clinically stable and underwent the planned hepatic resection after 4 wk,with an uneventful postoperative course.CONCLUSION Conventional portograms and careful evaluation prior to PVE are advisable to avoid such complications.

Analysis of Differential Metabolites in Selenium-enriched Rice Based on Extensive Non-targeted Metabolome

[Objectives]Selenium(Se)-enriched rice is the main type of Se-enriched agricultural product developed in China,and this study aimed to understand the impact of selenium application on the metabolites in rice.[Methods]Se-enriched rice was prepared by foliar application of a sodium selenite aqueous solution,and high-throughput analysis of differential metabolites in Se-enriched rice was conducted based on extensive non-targeted metabolome.[Results]There were significant differences in metabolites between Se-enriched rice and ordinary rice,and a total of 535 differential metabolites were identified.Among them,420 metabolites in Se-enriched rice were upregulated,accounting for 78.5%,far higher than downregulated metabolites.The enrichment differences of three KEGG metabolic pathways,including cysteine and methionine metabolism,zeatin biosynthesis,and arachidonic acid metabolism,reached a significant level,indicating that selenium enrichment had a significant regulatory effect on the metabolism of sulfur-containing amino acids,the synthesis of natural cytokinin zeatin,and arachidonic acid bioactive components in rice.[Conclusions]The results can provide a theoretical basis for the production of Se-enriched rice.

Safety Evaluation of Myricetin and Crude Extract from Myrica rubra Leaves on Non-target Organisms

[ Objective] The study aimed to supply important basis for developing environment-friendly pesticides with myricetin and crude extract of Myrica rubra leaves as effective components. [ Method] According to ＂Test guidelines for environmental safety evaluation on chemical pesticides＂, the toxicity of myricetin and crude extract of M. rubra leaves on non-target organisms was determined and the safety evaluation was carried out. [Result] MyriceUn and crude extract of M. rubra leaves had low toxicity on non-target organisms, such as earthworm, silkworm and soil microbes. Myricetin showed low toxicity and the crude extract of M. rubra leaves showed middle toxicity on tadpole. The high-concentration crude extract of M. rubra leaves had some antifeedant effect on silkworm. [ Conclusion] Myricetin and crude extract of M. rubra leaves had low toxicity on non-tar- get organisms in environment and they were relatively safe.

Research and countermeasures on how to improve English parole competence of contemporary college students under non-target language environment

Based on linguistic theories which developed by Saussure and some other contemporary linguists, this article attempts to analyze the factors that cause low English parole competence of the contemporary college students under non-target language environment. It views that how to properly deal with the relationship between langue and parole is still a debating focus in applied linguistics. The result of low English parole competence of contemporary college students is due to the interaction of the contemporary College English syllabus, text books pedagogies and the English language level of both students and teachers. Thus it puts forward some suggestions to improve the college students＇ English parole competence.

Effects of Transgenic Bt+CpTI Cotton on Field Abundance of Non-Target Pests and Predators in Xinjiang, China

Transgenic insect-resistant cotton is being increasingly planted in Xinjiang cotton-planting regions, where geographical climate conditions and species composition of pests and natural enemies are greatly unique in China. Limited studies have been conducted on the ecological impacts of transgenic insect-resistant cotton, especially for transgenic double genes （Bt＋CpTI） cotton, in this region. In this study, the potential effects of transgenic Bt＋CpTI cotton on the seasonal abundance of non-target pests and predators were assessed from 2009 to 2011 in Korla, Xinjiang. The results showed that species composition and seasonal abundance of 5 groups of pests and 5 groups of predators were not significantly different between transgenic Bt＋CpTI cotton and non-transgenic cotton every year. It suggests that transgenic Bt＋CpTI cotton per se does not affect the population dynamics of non-target pests and predators on this crop in Xinjiang.

Impact Assessments of Transgenic cry1Ab Rice on the Population Dynamics of Five Non-Target Thrips Species and Their General Predatory Flower Bug in Bt and Non-Bt Rice Fields Using Color Sticky Card Traps

A 2-yr field study was conducted to assess the effects of transgenic japonica rice（KMD1 and KMD2） with a synthetic cry1 Ab gene from Bacillus thuingiensis Berliner on population dynamics and seasonal average densities of five thrips species including Stenchaetothrips biformis（Bagnall）,Frankliniella intonsa（Trybom）,F.tenuicornis（Uzel）,Haplothrips aculeatus（Fabricius）,Haplothrips tritici（Kurd） and their general predatory flower bug,Orius similis Zheng as compared to the parental control rice line using the white,blue and yellow sticky card traps.Population dynamics and seasonal average densities of these five thrips species and their general predatory flower bug were not significantly affected by rice type.Additionally,the white sticky card trap was suggested to be the most suitable for monitoring the population of these five thrips species and their general predator.These results show that our tested Bt rice lines do not interrupt the population of non-target thrips species and their general predatory flower bug in the field,and also cannot result in more occurrence of these thrips species in the rice ecosystem.

Effect of Colored Sticky Cards on Non-target Insects

Field experiments to evaluate four different colored sticky cards for trapping non-target insects were conducted in an organic maize field in the Heinigou region of China. Yellow, blue, green, and red sticky cards were used to trap insects in the field. The total number of insects species caught was 54, with 3,862 individuals recorded. Over half of the specimens caught were non-target insects, including phytophagous insects, particularly dipteran species(including many mosquitoes)(50.3%), followed by target pests(37.0%), and beneficial insects(12.7%). Statistical analysis revealed a significant difference in attraction to target pests, non-target pests, and beneficial insects among treatment groups. The results showed that higher numbers of target pests(Myzus persicae Sulzer, Empoasca flavescens Fabricius, Nysius ericaecshinly Schilling) were caught on yellow sticky card traps compared with blue, green, or red sticky card traps, indicating that yellow was the best trap color for target pests, with green and blue being progressively less attractive. For non-target insects, including phytophagous insects, flies, and mosquitoes,higher numbers of were caught on blue sticky card traps compared with yellow,green, or red sticky card traps. Our study indicated that blue was the most attractive color for flies, especially for the housefly, Musca domestica Linnaeus. Our study also showed that most beneficial insects exhibited preferences to particular trap color characteristics: yellow was the most attractive color for parasitic wasps and lady beetles; blue was the most attractive color for hoverflies and honeybees. In contrast,green and red had no significant attraction to beneficial insects.

Non-target Screening and Quantitation of Organic Chlorides in Oilfield Chemicals with Comprehensive Two Dimensional Gas Chromatography Coupled with Time of Flight Mass Spectrometry

Advanced analytical methodology based on comprehensive two-dimensional gas chromatography-time of flight mass spectrometry(GC×GC-TOFMS) is proposed for investigation of organic chlorides in different oilfield chemicals.The target screening was initially carried out on 8 suspected organic chlorides by evaluating the capability of the enhanced separation and reliable identification at a trace concentration. GC×GC-TOFMS allowed for the fast and automated analysis of organic chlorides at a level of 200 μg/L. This method was subsequently applied for non-target screening of organic chlorides in different oilfield chemicals at various locations across China. 22 organic chlorides were identified and verified by comparison with pure standards in the mixed sample. Finally, this method was used to determine the content of the organic chlorides in individual samples. The result showed that the organic chloride levels in 19 of the 39 tested oilfield chemicals were above the threshold limit of 1.0 mg/L.

Non-target-site and target-site resistance to AHAS inhibitors in American sloughgrass(Beckmannia syzigachne)

American sloughgrass(Beckmannia syzigachne(Steud.) Fernald) is one of the most competitive and malignant weeds in rice-wheat rotation fields in China. American sloughgrass populations in the Jiangsu Province of China became less sensitive to acetohydroxyacid synthase(AHAS) inhibitors after repeated application for many years in these areas. Two suspected resistant American sloughgrass populations(R1 and R2) collected in the field were detected the resistance to inhibitors of AHAS in whole-plant dose-response assays, compared to the susceptible(S) population. These assays indicated that R1 showed low resistance to mesosulfuron-methyl(3.32-fold), imazapic(2.84-fold) and pyroxsulam(1.55-fold), moderate resistance to flazasulfuron(4.67-fold) and pyribenzoxim(7.41-fold), and high resistance to flucarbazone(11.73-fold). However, using a combination of the cytochrome P450 inhibitor, malathion, with mesosulfuron-methyl resulted in a reduction in R1 resistance relative to mesosulfuron-methyl alone. Furthermore, R2 was highly resistant to flazasulfuron(34.90-fold), imazapic(11.30-fold), flucarbazone(49.20-fold), pyribenzoxim(12.94-fold), moderately resistant to mesosulfuron-methyl(9.77-fold) and pyroxsulam(6.26-fold), and malathion had no effect on R2 resistance to mesosulfuron-methyl. The fulllength of AHAS genes was sequenced and the AHAS enzymes were assayed in vitro in order to clarify the mechanism of resistance to AHAS inhibitors in R1 and R2 populations. The results demonstrated that R2 had a Pro-197-Ser mutation in the AHAS gene, and the sensitivity of R2 to the five AHAS inhibitors was decreased, which may result in R2 resistance to AHAS inhibitors. There was no mutation in the AHAS gene of R1, and there were no significant differences in enzyme sensitivity between susceptible(S) and resistant(R1) populations. An enhanced metabolism may be the main mechanism of R1 resistance to AHAS inhibitors.

Thrips-mediated impacts from transgenic rice expressing Cry1Ab on ecological fitness of non-target predator Orius tantilus(Hemiptera:Anthocoridae)

Various rice lines have been genetically modified with genes from Bacillus thuringiensis（Bt） to continuously produce Bt insecticidal proteins against lepidopteran larvae. The Bt insecticidal protein constantly expresses in the plants to create an opportunity for non-target herbivores to acquire and convey the protein to their predators or parasitoids across trophic levels. This paper evaluates the effects of Bt rice（namely, Kemindao 1（KMD1） and Kemindao 2（KMD2）） expressing Cry1 Ab as compared to its non-Bt control line, Xiushui 11 on non-target predator Orius tantilus（a generalist predatory anthocorid of thrips） under laboratory and field conditions. To measure several biological parameters such as total nymphal duration and fecundity of this bug, it was reared on thrips and pollens of KMD1 and KMD2 as compared to their control under laboratory conditions. By comparison with the control, Bt rice did not significantly affect main life-history characteristics（total nymphal duration, female adult longevity, oviposition period and fecundity） of this anthocorid preying on Bt rice-fed thrips along with Bt rice pollens, except that the fecundity of this predator for KMD1 was distinctly lower as compared with KMD2 or the control. Enzyme-linked immunosorbent assay（ELISA） results showed that no Cry1 Ab protein was detected in this predator fed on thrips or rice pollen from Bt rice but was in Bt rice pollens. With the beat plate, plastic bag and color trap sampling methods, two-year field monitoring of O. tantilus abundance demonstrated that Bt rice had no significant detrimental effects on the population dynamics and seasonal average densities of this predatory anthocorid as compared with the control. Thus, it is suggested that growing our tested Bt rice（KMD1 and KMD2） producing Cry1 Ab will pose a negligible risk to the anthocorid, O. tantilus.

Semi-volatile organic compounds in a museum in China:A non-targeted screening approach

Non-targeted analysis(NTA)was conducted to identify semi-volatile organic compounds(SVOCs)in a museum in China using the gas chromatography(GC)-Orbitrap-mass spectrometer(MS).Approximately 160 SVOCs were detected,of which 93 had not been reported in previous studies of museum environments.Many of the detected SVOCs were found to be associated with the chemical agents applied in conservation treatment and the materials used in furnishings.The results of hierarchical cluster analysis(HCA)indicated a spatial variation of SVOCs in the indoor air in the museum,but there were no obvious temporal differences of SVOCs observed in indoor dust.Spearman's correlation analysis showed that several classes of SVOCs were well correlated,suggesting their common sources.Fragrances and plasticizers were found to be the primary sources of SVOC pollution detected in the museum.Compared with compounds in outdoor air,indoor SVOCs had a lower level of unsaturation and more portions of chemically reduced compounds.This study is the first of its kind to comprehensively characterize SVOCs in a museum using an automated NTA approach with GC-Orbitrap-MS.The SVOCs identified in the current study are likely to be present in other similar museums;therefore,further examination of their potential impacts on cultural heritage artifacts,museum personnel,and visitors may be warranted.

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。

杂草对9类常用不同作用机制除草剂的非靶标抗性机制研究进展

除草剂的应用为农业生产带来便利,但长期、单一使用某一种或相同机制的除草剂也引发了杂草对除草剂的抗性问题。抗性杂草种类逐渐增加,抗性形成机制复杂,导致农田杂草的治理难度增加。杂草对除草剂的抗性机制主要分为两种,一种是除草剂靶标位点基因的突变或过量表达导致的靶标抗性,另一种是杂草对除草剂吸收、转运、固存和代谢等一个或多个生理过程发生变化导致的非靶标抗性。本文综述了杂草对9类不同作用方式除草剂的非靶标抗性机制的生理、生化和分子基础的研究进展,以期为抗性杂草综合治理提供参考。

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。

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。

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。

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。

基于广泛代谢组学解析不同品种李果实代谢物的差异

利用非靶向代谢组学对广东5个不同品种/系李果实进行代谢物分析,共检出951种代谢物,其中初级代谢物489种、次级代谢物315种。5个品种李果实初级代谢物中脂类含量最高,其次是糖类、醇类、氨基酸类、有机酸类,核苷酸和维生素含量相对较少;次级代谢物中多酚类化合物含量最高,其次是植物激素、生物碱和萜类,苯丙素和木脂素类含量较少。大蜜李果实中脂类含量最高的是十一烷酸,占脂类总量的92.9%;糖类含量在大蜜李果实中仅次于脂类,其中松二糖含量最高,其含量为蔗糖的9.5倍、葡萄糖的8倍及果糖的14.6倍,可能是其具有蜜味的主要贡献因子;初级代谢物种类最多的是氨基酸及其衍生物,共鉴定到170种;L-苹果酸是主要的有机酸组分,占总有机酸及其衍生物含量的57.1%;维生素类中VB6含量最高,占比达51.5%;多酚类化合物中含量最多的是类黄酮,占比达77.7%。对其余4个品种与大蜜李果实分别进行代谢物差异分析,结果表明:青皮李与大蜜李的差异代谢物84种;小蜜李与大蜜李的差异代谢物73种;红线李与大蜜李的差异代谢物113种;大果迟熟三华李与大蜜李的差异代谢物34种,对差异代谢物富集的代谢途径进行分析发现,4组的差异代谢物主要富集于氨基酸、类黄酮、花青素、生物碱等合成代谢途径。大果迟熟三华李与大蜜李差异代谢物主要有C-戊糖基-木犀草素-C-己糖苷、多巴胺、三叶苷等类黄酮和酚类物质,以及烟酰胺腺嘌呤二核苷酸、β-烟酰胺单核苷酸等核苷酸类,这些物质可能是二者出现成熟期差异的关键物质。