Pollution Characteristics and Ecological Impact of Screening Analysis of Fishing Port Sediments from Dalian,North China

Environmental pollution from synthetic chemical mixtures has significant adverse impacts on marine ecosystems.However,identifying the main constituents of chemical mixtures that pose ecological threats is challenging due to the necessity of an integrated workflow for comprehensive identification and toxicological prioritization of pollutants.Here,an all-in-one mass spectrometric strategy integrating target,suspect,and nontarget analysis was used to investigate organic pollutants of concern in fishing port sediments,with 355 pollutants(32 from target analysis,118 from suspect screening and 205 from nontarget analysis)identified in 11 categories.The chemical classes of polycyclic aromatic hydrocarbons(PAHs),pesticides,and intermediates were the extensively detected chemical classes.The ecological risks of absolutely quantified pollutants(i.e.,16 parent PAHs,7 organophosphate esters(OPEs),10 pesticides and 4 benzotriazole ultraviolet absorbers)were assessed using toxicity-weighted concentration ranking,with o,p’-DDT being the major contributor.Under the toxicological priority index(ToxPi)framework,an extended ranking of all identified pollutants was achieved by combining instrument response and detection frequency,with a priority control list of 15 pollutants obtained,of which benzo[ghi]perylene(BghiP)and p,p’-DDE had the highest risk priority.Due to frequent detection rates and significant environmental risks,routine monitoring of petroleum pollutants is considered essential.This study presents a general workflow that includes comprehensive identification and prioritization of pollutants,facilitating chemical management and ecological risk assessment.

引言

＂民以食为天,食以安为先＂。食品安全事关人民群众健康和生命安全,也关系到社会和谐稳定发展大局。近年来食品安全问题日益凸现：＂瘦肉精＂事件尘埃未落,＂染色馒头＂、＂牛肉膏＂、＂毒豆芽＂、＂塑化剂＂等等又接踵而来。据世界卫生组织估计,全球每年发生食源性疾病约10亿人次,食品安全问题已成为人类面临的最大健康问题。

Nano-silica particles enhanced adsorption and recognition of lysozyme on imprinted polymers gels

Molecular imprinting technology has a great potential to be used in protein separation and purification. In this work, lysozyme imprinted polyacrylamide gel was prepared with silica particles as a sacrificial template to generate macro-porosity for fast adsorption. The adsorption equilibrium time and adsorption capacity were 9 h and 56 mg/g respectively, which was 2 h less and 2.3-fold more than polymers without the sacrificial template. In order to test molecular imprinting polymers （MIPs） ＇ selectivity, bovine serum albumin （BSA） was chosen as interferent for binary adsorption tests. In addition, the adsorption selectivity was further investigated using different molar ratios of lysozyme to BSA with fixed total concentration of proteins, as well as using various total concentra- tions of proteins with an equimolar ratio of lysozyme to BSA. It has been proven that the total con- centration of proteins should be larger than 1.5 × 10^-7 mol/mL, when the molar ratio of BSA to Lyz is 1： 1, in order to effectively separate Lyz from the binary protein mixture. The macro-porous lyso- zyme molecularly imprinted polymers have less adsorption time, larger adsorption capacity, and bet- ter imprinting effect.

Advances in Research of Acanthopanax trifoliatus( L. ) Merr

Acanthopanax trifoliatus( L.) Merr is a common traditional Chinese herbal medicine in central and southern regions of China. It has high medicinal and edible value and mainly contains flavonoids,polysaccharides,saponins and volatile components. Its active extracts have antioxidant,anti-inflammatory,anti-fatigue,and analgesic effects. From the biological characteristics,effective chemical components,extraction methods,cultivation techniques,pharmacological effects,toxicological activities,and product development status,this paper reviewed in detail the research status of A. trifoliatus in China and abroad,to provide a scientific basis for in-depth research and development,and utilization of A. trifoliatus.

Comprehensive characterization and detection of nut allergens in bakery foods using Q-TOF mass spectrometry and bioinformatics

Food allergy is a growing health issue worldwide and the demand for sensitive,robust and high-throughput analytical methods is rising.In recent years,mass spectrometry-based methods have been established for multiple food allergen detection.In the present study,a novel method was developed for the simultaneous detection of almond,cashew,peanut,and walnut allergens in bakery foods using liquid chromatography–mass spectrometry.Proteins unique to these four ingredients were extracted,followed by trypsin digestion,quadrupole time-of-flight(Q-TOF)mass spectrometry and bioinformatics analysis.The raw data were processed by de-novo sequencing module plus PEAKS DB(database search)module of the PEAKS software to screen peptides specific to each nut species.The thermal stability and uniqueness of these candidate peptides were further verified using triple quadrupole mass spectrometry(QQQ-MS)in multiple reaction monitoring(MRM)mode.Each nut species was represented by four peptides,all of which were validated for label-free quantification(LFQ).Calibration curves were constructed with good linearity and correlation coefficient(r 2)greater than 0.99.The limits of detection(LODs)were determined to range from 0.11 to 0.31 mg/kg,and were compared with the reference doses proposed by Voluntary Incidental Trace Allergen Labelling(VITAL).The recoveries of the developed method in incurred bakery food matrices ranged from 72.5%to 92.1%with relative standard deviations(RSD)of<5.2%.The detection of undeclared allergens in commercial bakery food samples confirmed the presence of these allergens.In conclusion,this method provides insight into the qualitative and quantitative detection of trace levels of nut allergens in bakery foods.

Behaviors of Leucine and Isoleucine in Ion Mobility- Quadrupole Time of Flight Mass Spectrometry

In this study, ion mobility separation coupled with tandem mass spectrometry （IM-tandem MS） was utilized to investigate the ionization behaviors of two amino acids including leucine and isoleucine. Under the electrospray ionization （ESI） mode, two protonation sites in each molecular sturcture caused two forms of protomer. One arose from the amino being protonated （amino-protomer） and the other from the carboxyl being protonated （car- boxyl-protomer）. In the two-dimensional （drift time, m/z） spectrum, the protomers had the same mass, but the dis- tinguishable drift times and fragmentation patterns. For the characterization purpose, the theoretical collision cross section （CCS） values of the protomers were calculated and proven to be consistent with the experimental. Moreover, the quantified relationship between the amino acids and their protomers was evaluated. It showed that the abun- dance of the carboxyl-protomer was proportional to the concentration of the amino acid, whereas that of the amino- protomer did not have the same trend. Under the atmospheric pressure chemical ionization （APCI） mode, only the carboxyl-protomer was observed. In addition, the amino-protomer and the cluster ions observed under ESI were absent completely. The results demonstrate that the ionization mode impacts heavily on the ionization behaviors of leucine and isoleucine not only on the form of therir protomers but also On the quantified relationship.

Reliable screening of pesticide residues in maternal and umbilical cord sera by gas chromatography-quadrupole time of flight mass spectrometry

The widespread use of pesticides induces heavy adverse effects on human health,especially for the pregnant women and the newborns.In this study,a screening method has been developed for the determination of multi-pesticides in maternal and umbilical cord sera.All pesticides in sera were collected using solid phase extraction(SPE),and analyzed by gas chromatography-quadrupole time of flight mass spectrometry(GC-QTOF MS).To set up the quality criteria,a database of 50 pesticides was created and the accurate masses of 3 up to 5 representative ions with their intensity ratios were included for each pesticide.In addition,a novel"identification points"(IPs)system relying on the accurate MS1 and MS2 spectra was used to interpret the data for each suspected pesticide.The methodology was then applied to a pair of maternal and umbilical cord sera.A total of six pesticide residues were screened out successfully.In conclusion,GC-QTOF MS combined with an accurate mass database seemed to be one of the most efficient tools for systematic pesticide analysis.

Development of High Performance Liquid Chromatography and Mass Spectrometry: a Key Engine of TCM Modernization

Traditional Chinese Medicine(TCM) has been popular for thousand years in prevention and treatment of chronic diseases synergistically with Western medicine while producing mild healing effects and lower side effects. Although many TCMs have been proven effective by modern pharmacological studies and clinical trials, their bioactive constituents and the remedial mechanisms are still not well understood. Researchers have made great efforts to explore the real theory of TCM for many years with different strategies. Development of high performance liquid chromatography(HPLC) and mass spectrometry within recent decade can provide scientists with robust technologies for disclosing the mysterious mask of TCM. In this paper, important innovations of HPLC and mass spectrometry are reviewed in the application of TCM analysis from single compound identification to metabolomic strategy.