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Occurrence of Different Forms and Implications of Compound Specific sterols in Continental Sediments of the Northeast South China Sea

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Acta Geologica Sinica(English Edition) 2019年第2期93卷 420-429页

作者： QIU Hong ZOU Li ZHANG Minsheng ZHU Chaoqi JIA Yonggang College of Environmental Science and Engineering Ocean University of China Education Key Laboratory fo r Marine Environment and Ecology Ocean University of China The Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering Ocean University of China

The South China Sea(SCS) is one of the most productive and accumulative marginal shelves of organic carbon in the world. To expound the transformation and preservation of organic carbon in the Northeast SCS, where abundant oil and gas resources have been reported, compound specific sterols in free(FR), base hydrolytic(BH), and acid hydrolytic(AH) forms were analyzed in surface and columnar sediments in May, 2016. The results showed that the total contents of sterols detected ranged from 0.15 to 3.74 ppm dry weight in the surface sediments, and gradually decreased from 3.41 to0.17 ppm dry weight from surface to deep sediments, in which cholesterol(27^(△5)) was the most abundant component. sterols mainly existed in the BH form(54.51%-74.20%), followed by the FR form(25.50%-45.49%) and then the AH form(0-3.77%) in turn, in the surface sediments. BH and FR sterols accounted for 0-49.08% and 50.92%-100% in the columnar sediments, while AH sterols were undetectable. The contents of specific sterols indicated that, the primary source of marine organic carbon was about 5 times as much as that from terrestrial input. More and more FR sterols transformed into BH sterols with increasing sedimentary depth, and BH sterols absolutely dominated in sediment depths under 25 cm. The forms of sterols C27 were maintained at a relative consistence state, but sterols C28 to C30 degraded gradually during the sedimentation process. It was suggested that the stability of sterols, based on the chemical structures, might be the primary factor controlling their degradation and preservation in deeper sediments. These results would help to understand the organic carbon(OC) transformation in a hydrate formation area in a marginal sea.

关键词： sterols sediments occurrence forms transformation northeast South China Sea

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Faecal sterols as sewage markers in the Langat River,Malaysia:Integration of biomarker and multivariate statistical approaches

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Journal of Environmental Sciences 2012年第9期24卷 1600-1608页

作者： Nur Hazirah Adnan Mohamad Pauzi Zakaria Hafizan Juahir Masni Mohd Ali Centre of Excellence for Environmental Forensics Faculty of Environmental StudiesUniversiti Putra Malaysia 43400 SerdangSelangorMalaysia Department of Environmental Sciences Faculty of Environmental StudiesUniversiti Putra Malaysia43400 SerdangSelangorMalaysia School of Environmental and Natural Resource Sciences Faculty of Science and TechnologyUniversiti Kebangsaan Malaysia43600 BangiSelangorMalaysia

The Langat River in Malaysia has been experiencing anthropogenic input from urban, rural and industrial activities for many years. Sewage contamination, possibly originating from the greater than three million inhabitants of the Langat River Basin, were examined. Sediment samples from 22 stations （SL01-SL22） along the Langat River were collected, extracted and analysed by GC-MS. Six different sterols were identified and quantified. The highest sterol concentration was found at station SL02 （618.29 ng/g dry weight）, which situated in the Balak River whereas the other sediment samples ranged between 11.60 and 446.52 ng/g dry weight. Sterol ratios were used to identify sources, occurrence and partitioning of faecal matter in sediments and majority of the ratios clearly demonstrated that sewage contamination was occurring at most stations in the Langat River. A multivariate statistical analysis was used in conjunction with a combination of biomarkers to better understand the data that clearly separated the compounds. Most sediments of the Langat River were found to contain low to mid-range sewage contamination with some containing ＇significant＇ levels of contamination. This is the first report on sewage pollution in the Langat River based on a combination of biomarker and multivariate statistical approaches that will establish a new standard for sewage detection using faecal sterols.

关键词： sterols biomarkers surface sediments sewage pollution Langat River principal component analysis

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甾醇TMS衍生物EI源质谱规律研究

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分析测试学报 2008年第S1期27卷 59-62页

作者：缪妙徐继林严小军侯云丹宁波大学应用海洋生物技术教育部重点实验室浙江宁波315211

The mass spectrometric fragmentation of TMS derivatives of sterols was studied and analyzed based on the mass spectrometry of the TMS derivatives of standards.The double bond numbers and the degree of the methylize,alkylize and the related position in the sterol nucleus and the side chains were confirmed by the characteristic ions.Total lipids were extracted using Bligh-Dyer method.sterols were isolated by solvent partition with chloroform-hexane(1 ∶4,by volume),derivated by BSTFA,and analyzed by GC-MS.The regular pattern was used for identifying the sterols in a dinoflagellate from the Symbodinium sp.

关键词： TMS derivatives of sterols mass spectrometry Symbodinium sp.

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Triterpenoids and sterols from the Leaves and Twigs of Melia azedarach

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Natural Products and Bioprospecting 2014年第3期4卷 157-162页

作者： Wei-Ming Zhang Jie-Qing Liu Xing-Rong Peng Luo-Sheng Wan Zhi-Run Zhang Zhong-Rong Li Ming-Hua Qiu State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China University of Chinese Academy of Sciences Beijing 100049China

Two new triterpenoids(1 and 2)and a new sterol(3),together with six known constituents(4–9),were isolated from the leaves and twigs of Melia azedarach.Their chemical structures were elucidated on the basis of spectro... 详细信息

关键词： Meliaceae Melia azedarach Triterpenoids sterols

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New components regulating stomatal development:sterols and RNA polymerase Ⅱ

New components regulating stomatal development:sterols and R...

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第二届全国发育生物学大会

作者： Pingping Qian Liang Chen Suiwen Hou Key Laboratory of Cell Activities and Stress Adaptations Ministry of EducationSchool of Life SciencesLanzhou University

Stomata,the highly specialized epidermal structures consisting of paired,kidney-shaped guard cells,control transpiration and gas exchange between plants and the environment.Stomatal patterning represents an ideal system for analyzing plant cell division and differentiation.Many key genes regulating stomatal development have been identified and a regulatory network including ligands,receptors,a MAPK cascade,and transcription factors has been established.However,new components and mechanisms involved in stomatal development are needed to be uncovered.We isolated two new mutants named fk-J3158 and J3243 in an ethyl methanesulfonate mutagenesis screen.fk-J3158 is a weak allele of the Arabidopsis sterol C-14reductase gene FACKEL(FK)that shows clusters of small cells and stomata in leaf epidermis.Sterol profile analysis revealed that the fk-J3158 mutation blocked downstream sterol production and produced some exceptional sterol derivatives.Further investigation indicated that cyclopropylsterol isomerasel(cpi1),sterol 14ademethylase(cyp51A2)and hydral(hyd1)mutants,corresponding to enzymes in the same branch of the sterol biosynthetic pathway,displayed defective stomatal development phenotypes,similar to those observed for Jk.Fenpropimorph,an inhibitor of the FK sterol C-14 reductase in Arabidopsis,also caused these abnormal small-cell and stomata phenotypes in wild-type leaves.Genetic experiments demonstrated that sterol biosynthesis is required for correct stomatal patterning,probably through an additional signaling pathway that has yet to be defined.Detailed analyses of time-lapse cell division patterns,stomatal precursor cell division markers and DNA ploidy suggest that sterols are required to properly restrict cell proliferation,asymmetric fate specification,cell-fate commitment and maintenance in the stomatal lineage cells.These events occur after physical asymmetric division of stomatal precursor cells.These results would be essential for further revealing the mechanisms underlie cell-fate commitment and maintenan

关键词： stomata stomatal development sterols RNA polymerase Ⅱ

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Two New sterols from Adenophora Stenanthina Subsp.Xifengensi

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Chemical Research in Chinese Universities 1997年第4期13卷 98-101页

作者： HOU Zhen-fu SHIYan-ping MEI Shuang-xi LI Yu Institute of Or ganic Chemistry State Key Laboratory of Applied Organic ChemistryLanzhou UniversityLanzhou730000

ＴｗｏＮｅｗＳｔｅｒｏｌｓｆｒｏｍＡｄｅｎｏｐｈｏｒａＳｔｅｎａｎｔｈｉｎａＳｕｂｓｐ．ＸｉｆｅｎｇｅｎｓｉｓＨＯＵＺｈｅｎ－ｆｕ，ＳＨＩＹａｎ－ｐｉｎｇ，ＭＥＩＳｈｕａｎｇ－ｘｉａｎｄＬＩＹｕ＊（Ｉｎｓｔｉｔｕｔｅ... 详细信息

ＴｗｏＮｅｗＳｔｅｒｏｌｓｆｒｏｍＡｄｅｎｏｐｈｏｒａＳｔｅｎａｎｔｈｉｎａＳｕｂｓｐ．ＸｉｆｅｎｇｅｎｓｉｓＨＯＵＺｈｅｎ－ｆｕ，ＳＨＩＹａｎ－ｐｉｎｇ，ＭＥＩＳｈｕａｎｇ－ｘｉａｎｄＬＩＹｕ＊（ＩｎｓｔｉｔｕｔｅｏｆＯｒｇａｎｉｃＣｈｅｍｉｓｔｒ...

关键词： Adenophora stenanthina subsp.Xifengensis Campanulaceae Steroids sterols

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Intelligent geochemical interpretation of mass chromatograms: Based on convolution neural network

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PETROLEUM SCIENCE 2024年第2期21卷 752-764页

作者： Su, Kai -Ming Lu, Jun -Gang Yu, Jian Lu, Zi-Xing Chen, Shi-Jia Hubei Key Lab Petr Geochem & Environm Wuhan 430100 Hubei Peoples R China Yangtze Univ Coll Resources & Environm Wuhan 430100 Hubei Peoples R China Southwest Petr Univ Sch Geosci & Technol Chengdu 610500 Sichuan Peoples R China Changqing Oilfield Co PetroChina Xian 710021 Shaanxi Peoples R China

Gas chromatography-mass spectrometry (GC-MS) is an extremely important analytical technique that is widely used in organic geochemistry. It is the only approach to capture biomarker features of organic matter and provides the key evidence for oil-source correlation and thermal maturity determination. However, the conventional way of processing and interpreting the mass chromatogram is both timeconsuming and labor-intensive, which increases the research cost and restrains extensive applications of this method. To overcome this limitation, a correlation model is developed based on the convolution neural network (CNN) to link the mass chromatogram and biomarker features of samples from the Triassic Yanchang Formation, Ordos Basin, China. In this way, the mass chromatogram can be automatically interpreted. This research first performs dimensionality reduction for 15 biomarker parameters via the factor analysis and then quantifies the biomarker features using two indexes (i.e. MI and PMI) that represent the organic matter thermal maturity and parent material type, respectively. Subsequently, training, interpretation, and validation are performed multiple times using different CNN models to optimize the model structure and hyper-parameter setting, with the mass chromatogram used as the input and the obtained MI and PMI values for supervision (label). The optimized model presents high accuracy in automatically interpreting the mass chromatogram, with R2 values typically above 0.85 and 0.80 for the thermal maturity and parent material interpretation results, respectively. The significance of this research is twofold: (i) developing an efficient technique for geochemical research; (ii) more importantly, demonstrating the potential of artificial intelligence in organic geochemistry and providing vital references for future related studies. (c) 2023 The Authors. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.

关键词： Organic geochemistry Biomarker Mass chromatographic analysis Automated interpretation Convolution neural network Machine learning TRIASSIC YANCHANG FORMATION ORDOS BASIN BIOMARKERS PALEOENVIRONMENT EXPLORATION PREDICTION TERPANES sterols MARKERS SHALES

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Determination of sterols from Sediment Samples Using Pressurized Liquid Extraction and GC/MS

Determination of Sterols from Sediment Samples Using Pressur...

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第三届全国环境化学学术大会

作者：陈铁李东浩董美花吴学延边大学分析测试中心延边大学分析测试中心延边大学分析测试中心延边大学分析测试中心

＜正＞sterols are widespread environmental chemicals with long persistency in sediment even in geologic periods [1]. Most of them were found in river and costal area polluted by human and animal swage. To determine extend of human and animal waste in the environment;sterols were monitored as a tracer of fecal in water, suspended particle and sediment in previous studies [2].

关键词： sterols PLE Sediment Silyl derivatives GC/MS

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The substance composition of sterols in the sediments from the Chukchi Sea,the Bering Sea and global climatic significance

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Chinese Journal of Polar Science 2006年第1期17卷 9-19页

作者：卢冰扈传昱潘建明薛斌姚梅 Laboratory of Marine Ecosystem and Biogeochemistry State Oceanic Adminastration Hangzhou 310012 China

The compounds of sterols such as C27 ,C2s ,C29 and C30 are recorded from C-8 core of the Chukchi Sea. The double bond position is located at 5-, 5,22 as well as 22-,24-. The compound of sterols such as C27 ,C28 ,C29 are recorded from B2-9 core of the Bering Sea. The double bond position is located at 5-, 5, 22 as well as 22. The composition characteristics of sterols indicate that the substance is mainly contributed by the terrigenous origin and marine silicate organisms. The results are also suggest that the record of abnormal sterols from the surface sediments （2 -0 era）in the Chukchi Sea and the Bering Sea represent the period from 1980s to the late 1990s. The strong signal of the Arctic warming is preserved in the sediments, which indicates the eco - environmental change responding to climatic effect of circumjacent.

关键词： the Chukchi Sea the Bering Sea biological indicator sterols substance composition.

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Kuroshio Intrusion Combined with Coastal Currents Affects Phytoplankton in the Northern South China Sea Revealed by Lipid Biomarkers

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Journal of Ocean University of China 2023年第2期22卷 576-586页

作者： WANG Yaoyao BI Rong GAO Jiawei ZHANG Hailong LI Li DING Yang JIN Gui’e ZHAO Meixun Frontiers Science Center for Deep Ocean Multispheres and Earth System and Key Laboratory of Marine Chemistry Theory and TechnologyMinistry of EducationOcean University of ChinaQingdao 266100China Laboratory for Marine Ecology and Environmental Science Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China

The northern South China Sea(NSCS)is significantly influenced by the Kuroshio intrusion and the coastal currents.Our knowledge on the roles of both currents on phytoplankton spatial variations is still inadequate.Here,we investigated the concentrations of phytoplankton biomarkers and their proportions in surface suspended particles from 47 sites of the NSCS during summer of 2017 and 2019.Brassicasterol/epi-brassicasterol,dinosterol,and C37 alkenones were used as proxies of biomass for diatoms,dinoflagellates,and haptophytes,respectively,and their sum indicating total phytoplankton biomass.A three end-member mixing model was applied to quantitatively assess the influence extent of the Kuroshio intrusion and the coastal currents.Our results showed that the Kuroshio intrusion and the coastal currents contributed equally to the overall surface water masses in the study area;however,the two currents had distinct effects on the spatial distribution of phytoplankton.For phytoplankton biomass,the eutrophic coastal currents were likely to be the main controlling factors,while the impact of the Kuroshio intrusion was weak and stimulated significant increases in phytoplankton biomass only at certain boundary sites.For phytoplankton community structures,the Kuroshio and its intrusion were the main factors,resulting in an increase in the proportions of dinoflagellates and haptophytes.The proportion of diatoms slightly increased due to the influence of the coastal currents.Our study quantifies the effects of the Kuroshio and the coastal currents on phytoplankton in the NSCS in terms of hydrological parameters,providing an important basis for the understanding of ecological functions and biogeochemical cycles in marginal sea-open ocean boundary regions.

关键词： sterols alkenones phytoplankton northern South China Sea Kuroshio coastal currents

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