Validation of a Method for Characterization of Ethanol in Water by HS-GC-FID to Serve the Traceability of Halal Measurements

The determination of the ethanol content in food products is of fundamental importance for HALAL certification. In this work, an analytical method for the determination of ethanol in water by headspace gas chromatography with flame ionization detector (HS-GC-FID) has been developed and validated for the use in characterization of ethanol reference materials. The validation study was carried out in the linear calibration range 100 - 1500 mg/kg using the NIST SRM 2900, nominal 95.6%. The studied performance characteristics of the method were the limit of detection, LOD, the limit of quantification LOQ, selectivity, linearity, precision, recovery and bias. The validation results showed that the method is selective, precise, accurate and free from any significant bias. The LOD and LOQ were 1.27 and 3.86 mg/kg respectively and the estimated expanded uncertainty was 2% indicating that the method is fit for the purpose of certification of ethanol in water reference materials.

Relationship and effect of redox potential,jarosites and extracellular polymeric substances in bioleaching chalcopyrite by acidithiobacillus ferrooxidans

The changes of pH,redox potential,concentrations of soluble iron ions and Cu^2＋ with the time of bioleaching chalcopyrite concentrates by acidithiobacillus ferrooxidans were investigated under the different conditions of initial total-iron amount as well as mole ratio of Fe（III） to Fe（II） in the solutions containing synthetic extracellular polymeric substances （EPS）.When the solution potential is lower than 650 mV （vs SHE）,the inhibition of jarosites to bioleaching chalcopyrite is not vital as EPS produced by bacteria can retard the contamination through flocculating jarosites even if concentration of Fe（III） ions is up to 20 g/L but increases with increasing the concentration of Fe（III） ions;jarosites formed by bio-oxidized Fe3＋ ions are more easy to adhere to outside surface of EPS space on chalcopyrite;the EPS layer with jarosites acts as a weak diffusion barrier to further rapidly create a high redox potential of more than 650 mV by bio-oxidizing Fe^2＋ ions inside and outside EPS space into Fe^3＋ ions,resulting in a rapid deterioration of ion diffusion performance of the EPS layer to inhibit bioleaching chalcopyrite severely and irreversibly.

Interaction mechanism of Cu^(2+),Fe^(3+) ions and extracellular polymeric substances during bioleaching chalcopyrite by Acidithiobacillus ferrooxidans ATCC2370

The extracellular polymeric substances（EPS） of Acidithiobacillus ferrooxidans ATCC 23270,and iron and copper enclosed in EPS were extracted by ultrasonication and centrifugation methods to determine the interaction mechanism of Cu2＋,Fe3＋ and EPS during bioleaching chalcopyrite.Generally,Cu2＋ ions can stimulate bacteria to produce more EPS than Fe3＋ ions.The mass ratio of Fe3＋/Cu2＋ enclosed in EPS decreased gradually from about 4：1 to about 2：1 when the concentration of Cu2＋ ions increased from 0.01 to 0.04 mol/L.The amount of iron and copper bound together by EPS in ferrous-free 9K medium containing 1% chalcopyrite was about 2 times of that in 9K medium containing 0.04 mol/L Cu2＋ ions.It was inferred that the EPS with jarosites on the surface of chalcopyrite gradually acted as a weak diffusion barrier for Cu2＋,Fe3＋ ions transference during bioleaching chalcopyrite.

探讨NLR、PLR、hs-CRP、Hb、D-D与ACI非溶栓治疗后出血性转化的相关性分析

目的 探讨急性脑梗死患者(ACI)非溶栓治疗前血清中性粒细胞与淋巴细胞比值(NLR)、血小板与淋巴细胞比值(PLR)、超敏C反应蛋白(hs-CRP)、血红蛋白(Hb)、D-二聚体(D-D)与治疗后出血性转化(HT)的相关性,以期为临床预防ACI非溶栓治疗后发生提供指导依据。方法 本研究病历组(设为转化组)共纳入80例样本,选取自2015年1月至2019年12月在吉林大学第一医院检验科接受非溶栓治疗后并出现HT的ACI患者,根据HT严重程度等级化分1级、2级、3级、4级,各严重程度患者分别为27例、22例、18例、13例。选取50例在接受非溶栓治疗后未出现HT的ACI患者作为对照(非转化组)。比较各组的血清NLR、PLR、hs-CRP、Hb、D-D表达水平差异,并通过Spearman秩相关检验分析NLR、PLR、hs-CRP、Hb、D-D与HT严重程度的相关性。并采用ROC曲线分析NLR、PLR、hsCRP、Hb、D-D对ACI患者HT的预测作用。结果 转化组的血清NLR、PLR、hs-CRP、D-D表达水平均高于非转化组,Hb的表达水平低于非转化组(均P<0.05)。1级、2级、3级、4级患者的血清NLR、PLR、hs-CRP、D-D表达水平依次上升,Hb表达水平依次降低,差异有统计学意义(P<0.05),且组间两两比较,差异有统计学意义(P<0.05)。ACI非溶栓治疗后HT严重程度与血清NLR、PLR、hs-CRP、D-D均呈正相关(r值分别为:0.729、0.692、0.601、0.578,均P<0.05),与Hb呈负相关(r值为:-0.678,P<0.05)。ROC曲线分析显示,NLR的AUC值为0.896[95%CI(0.737~0.962)]、PLR的AUC值为0.775 [95%CI(0.626~0.917)]、hs-CRP的AUC值为0.840 [95%CI(0.712~0.948)]、Hb的AUC值为0.782 [95%CI(0.493~0.914)]、D-D的AUC值为0.725 [95%CI(0.403~0.852)]。结论 ACI患者的NLR值、PLR值、hs-CRP、Hb、D-D表达水平与其在非溶栓治疗后发生HT存在相关性,临床上可将这些指标作为预测HT风险。

HS-GC-MS联用测定河南传统西瓜豆酱中的挥发性成分

以河南传统发酵的西瓜豆酱为研究对象,采用自动顶空进样-气质联用(HS-GC-MS)法测定其挥发性成分。通过单因素试验分别考察了平衡温度、平衡时间、震动频率及样品氯化钠的添加量对挥发性成分的影响。结果表明,平衡温度90℃,平衡时间50 min,震动频率6次/秒,不添加氯化钠为测定较优条件。在此条件下,鉴定出自然发酵西瓜豆酱中挥发性成分有10类共82种,其中醇类12种,酯类10种,烯烃类14种,醛类6种,酮类8种,醚类4种,酸类1种,烷烃类10,含N化合物7种和其他10种。相对含量较高的是烯烃类、醛类和醇类,分别为23.848%,22.537%和19.743%,三者之和占挥发性成分总量的66.12%,其次是酯类和酮类,分别占11.945%和6.839%,这三种成分对河南传统西瓜豆酱的特征风味起着至关重要的作用。

15-15hs Max材料枪钻加工的钻削力和切屑分析

高氮奥氏体不锈钢15-15hs Max具有优秀的耐蚀性、良好的综合力学性能,但切削加工性差,属于一种难加工材料。以某石油钻探部件为研究对象,对15-15hs Max的加工特性进行分析,通过对15-15hs Max钻削过程的有限元仿真,分析其加工过程中的钻削力和切屑形态的变化。仿真结果表明:钻削力会随着钻入深度的增加而增加,当切削刃全部参与切削时钻削力达到稳定,加工过程中形成的切屑为向上弯曲的螺旋状切屑。在保证加工孔质量及加工效率条件下,得出了一组较为合理的钻削参数。

Analysis of bacitracin and its related substances by liquid chromatography tandem mass spectrometry

A suitable liquid chromatography quadrupole time-of-flight mass spectrometric(LC–Q-TOF–MS) method was developed for separation and characterization of related substances in bacitracin test drug. The separation was performed on Li Chrospher RP-18 column using methanol as mobile phase A and 0.2% ammonium acetate buffer solution as mobile phase B in gradient elution. A total of 12 related substances were detected through high resolution mass spectrometric determination in a positive electrospray ionization mode. They were identified as co-existing active components and degradation products of bacitracin through the analysis and elucidation of both the protonated parents and the product ions of all the related substances and their fragmentation pathways were also proposed.

Competitive Complexation of Copper and Zinc by Sequentially Extracted Humic Substances from Manure Compost

Chicken manure with similar content of copper and zinc was changes of organic carbon and humus substance complexed chosen to conduct a composting experiment to investigate the copper （HS-Cu） and zinc （HS-Zn）, which were extracted by water （H2O）, sodium hydroxide （NaOH）, and sodium pyrophate-NaOH mixture （Na4P2O7-NaOH）, sequentially. Distributions of copper and zinc in fulvic acids （FA） and humic acids （HA） in the three extracts were studied. During manure composting, the concentrations of copper and zinc increased from about 500 mg kg^-1 in the raw material to 1 100 mg kg^-1 in the final products. HS-Cu in H2O, NaOH, and Na4P2O7-NaOH extracts occupied 6.7, 26.7, and 19% averagely of total copper and HS-Zn represented 2.7, 13.7, and 17% averagely of total zinc in compost, respectively. In water extracts, both HA and FA mainly complexed with Cu and the mole ratio of Cu to Zn was 2.8 in HA fractions and was 2.6 in FA fractions, respectively. HA mainly complexed with copper, so that the ratios of HA-Cu to HA-Zn averaged 3.4 in NaOH extracts. FA had a similar potential to complex with copper and zinc, so that the ratio of FA-Cu to FA-Zn was close to 1. In Na4P2O7-NaOH extracts, HA or FA had a similar potential to complex with copper and zinc. The ratio of HS-Cu to HS-Zn was close to 1. With manure composting, Na4P2O7-NaOH extractable HS-Zn increased to a level as high as HS-Cu. This indicated that more and more stable complexes of HS-Zn were formed in the late decomposition period. The competition between copper and zinc to be complexed with humic substance became weaker and weaker with the decomposition process.

Enhancement of Phosphorus Solubility by Humic Substances in Ferrosols

An investigation was conducted to study the effect of humic substance (HS) on the phosphorus (P) solubility in acidic soil. The soil (2.5 g), HS (0, 0.5, and 2.5 g), and P as monocalcium phosphate (0.31 and 1.25 g P kg-1 soil) were mixed with 50 mL distilled water and two different sequences of adding HS and P were used. The results indicated that the P concentration in water and 0.01 mol L-1 CaCl2 solution increased with increasing amounts of humic substance. The concentrations of Fe and Al were also increased. However, Olsen P decreased with increasing amount of humic substance. Water-soluble P concentrations from P rates at 0.31 and 1.25 g P kg-1 soil in the treatment with 0.5 g (2.5 g) humic substance addition were 360% and 70% (500% and 90%) higher, respectively, than those in the treatment with no humic substance addition. P extracted by 0.01 mol L-1 CaCl2 in the treatments with 0.5 and 2.5 g humic substance addition was increased by 400% and 540%, respectively, compared with that in the treatment without humic substance at the rate of 0.31 g P kg-1 soil, while the corresponding P concentrations were increased by 80% and 90% at the rate of 1.25 g P kg-1 soil. The order of mixing humic substance and phosphate did not significantly affect desorbed P and labile P extracted with CaCl2.

hs-CRP、CCL2、CCL3与新生儿细菌感染病情关系及疗效预测价值

目的探讨超敏C反应蛋白(hs-CRP)、趋化因子CC基序配体(CCL)、CCL3与新生儿细菌感染病情关系及疗效预测价值。方法选取2021年1月至2023年1月廊坊市人民医院收治的70例新生儿细菌感染患儿作为细菌感染组,另按照1∶1比例选取70例新生儿病毒感染患儿、70例非感染性新生儿分别作为病毒感染组、对照组。比较3组及细菌感染组不同病情程度患儿入院时血清hs-CRP、CCL2、CCL3,比较细菌感染组不同疗效患儿血清各指标,绘制受试者工作特征曲线(ROC)分析血清各指标对治疗效果预测效能,用相对危险度(RR)分析血清各指标不同表达对新生儿细菌感染治疗效果的影响。结果细菌感染组、病毒感染组入院时血清hs-CRP、CCL2、CCL3表达均高于对照组(P<0.05);细菌感染中重症患儿入院时血清hs-CRP、CCL2、CCL3表达高于轻症患儿(P<0.05),入院时及入院24 h、第3天、第5天无效亚组血清hs-CRP、CCL2、CCL3表达均高于有效亚组(P<0.05);入院时及入院24 h、第3天、第5天血清hs-CRP、CCL2、CCL3联合预测新生儿细菌感染疗效价值优于各时间点的单一指标预测效能,其中入院24 h各指标联合预测AUC最大;以入院24 h各指标截断值为界分为高表达、低表达,hs-CRP、CCL2、CCL3高表达患儿治疗无效风险是低表达患儿的3.577倍、3.357倍、2.630倍。结论在新生儿细菌感染血清中hs-CRP、CCL2、CCL3高表达,且与患儿病情程度、治疗效果密切相关,3者血清各指标联合在预测患儿治疗效果中具有良好的参考价值。

Removal of humic substances by biosorption

Fungal pellets of Aspergillus niger 405,Aspergillus ustus 326,and Stachybotrys sp.1103 were used for the removal of humic substances from aqueous solutions.Batchwise biosorption,carried out at pH 6 and 25°C,was monitored spectrophotometrically and the process described with Freundlich’s model.Calculated sorption coeffcients Kf and n showed that A.niger exhibited the highest effciency.A good match between the model and experimental data and a high correlation coeffcient(R2)pointed out to judicious choice of ...

Purification of Two Antimicrobial Substances Produced by Bacillus subtilis Strain B11 and Their Properties

Two antimicrobial substances produced by Bacillus subtilis strain B 11 were purified by boiling, DEAE 52 anion exchange chromatography and aluminum oxide adsorption chromatography, These purified substances showed only one spot on silica gel thin layer chromatography （TLC）. Antimicrobial assays showed that antimicrobial substances A and B inhibited the growth of plant pathogens such as Fusarium oxysporum Schl f.sp. niveum, Rhizoctonia solani, Ralstonia solanacearum and Xanthomonas oryzae pv. oryzae. In addition, antimicrobial substance B could also inhibit the growth of Magnaporthe grisea. These two antimicrobial substances were resistant to proteolytic enzymes and temperature as high as 121℃.

ADSORPTION OF HUMIC SUBSTANCES BY MACRO WEAKLY BASIC IONEXCHANGE RESIN AND THEIR EFFECTS ON REMOVAL OF Cu^(2+) AND Pb^(2+)

Adsorption of humic, tannic and gallic acids by a macro weakly basic ion-exchange resin JN-01 was studied. The adsorption capacity of this resin for gallic and tannic acids is much higher than that for humic acid, which can be explained on the basis of both their molecular size and ionization degree. Furthermore, humic acid is separated into different components with molecular weight in the range from 2000 Da to 100000 Da by ultra-filter, and their adsorption isotherms on resin JN-01 indicate that humic acid＇s molecular weight is an important factor which makes significant influence on adsorption. Finally, changes in the amount of Cu^2＋ and Pb^2＋ adsorbed on resin JN-01 as a function of the concentration of each of these three acids were studied. A large increase in the heavy metal ions uptake is observed in the presence of humic substance, such advantages are due to the interactions between the heavy metal ions and the unbound functional groups of the adsorbed organic acids.

Studies on Fermentation Conditions of Antimicrobial Substances Produced by Brevibacillus laterosporus BL-21

[Objective] Brevibacil us laterosporus BL-21 was inhibitory to Gibberel a sanbinetti, Fusarium graminearum Magnaporthe grisea and many other phy-topathogenic fungi. Antimicrobial substances can be increased through optimizing the medium of Brevibacil us laterosporus. [Method] A total of 10 factors were tested for their function of improving antibiotics yield of BL-21 by single-factor test. And the indicative bacterium was screened. [Result] The best indicative bacterium was Al-ternaria solani, the optimum process parameters in shaking flask on fermentation consisted of initial pH of 8.0, culture at 30 ℃, loadage 90 ml/250 ml, rotation 180 r/min, and fermentation time of 48 h. The results also indicated that glucose was the best carbon source for the antibiotics productivity of BL-21, and beef extract was the best nitrogen source. In addition, univalent ion Cl＋ and divalent ion Mn2＋ stimu-lated BL-21 antibacterial active component biosynthesis. [Conclusion] Optimized medi-um is more conducive to produce antimicrobial substances.

基于HS-GC-IMS分析陇南主栽品种初榨橄榄油的风味特征成分

旨在为我国甘肃陇南产区初榨橄榄油(VOO)的快速鉴别以及工业生产过程中的风味品质评价提供数据支撑和理论依据,采用HS-GC-IMS技术对甘肃陇南主栽品种莱星(LX)、佛奥(FO)、科拉蒂(KLD)、皮削利(PXL)、鄂植8号(EZ8)以及LX与KLD的混合品种(HH)6种VOO中的风味特征成分进行定性和差异分析。结果表明:6种VOO中共检测出39种风味特征物质,定性出22种,其中醛类(9种)、酮类(5种)化合物为主要的风味特征成分,此外还包括酯类(3种)、醇类(3种)、萜烯类(1种)和呋喃类(1种)等物质;6种VOO中含有的风味特征物质均存在不同程度的差异,其中,LX、KLD和HH中的风味特征物质较为相似,其2-甲基丁醛、3-甲基丁醛、(E)-2-戊烯醛、辛醛和2-正戊基呋喃含量较高,FO中的正戊醇、正己醛和3-戊酮含量较高,PXL中的(Z)-3-己烯乙酸酯、α-松油烯、2-己酮的含量较高,EZ8中的乙酸乙酯含量最高,HH中的2-丁酮、丙酮、(E)-2-庚烯醛的含量较高。综上,采用HS-GC-IMS可以有效检测VOO中的风味特征物质,定性出的风味特征物质可作为区分6种VOO的依据之一。

Comparison of Flavor Substances in Dried Shrimp Products Processed by Litopenaeus Vannamei from Two Aquaculture Patterns

Dried shrimp is a popular aquatic food worldwide due to its unique flavor.However,its flavor qualities on the market remain uneven.This study aimed to compare flavor substances in dried shrimp processed by Litopenaeus vannamei from two aquaculture patterns(earthen pond and greenhouse)using amino acid automatic analyzer,high-performance liquid chromatography(HPLC),gas chromatography(GC)-ion mobility spectrometry(IMS),and GC-mass spectrometry(GC-MS).The results revealed that dried shrimp from earthen pond had significantly higher free amino acids and 5’-nucleotides than those from greenhouse(P<0.05),and their corresponding equivalent umami concentrations(EUCs)were 23.45 g MSG(100 g)^(−1)and 14.86 g MSG(100 g)^(−1),respectively.For volatile compounds,GC-IMS analysis indicated significant differences in volatile compounds between dried shrimp from different aquaculture patterns.According to the quantitative analysis of GC-MS,11 volatile compounds were identified as aroma-active compounds(AACs),of which six AACs(1-octen-3-ol,3-methylbutanal,nonanal,trimethylamine,2,5-dimethylpyrazine,and 2,3,5-trimethylpyrazine)were found in all dried shrimp samples.Although dried shrimp from greenhouse possesses higher OAVs,OAVs of(E,E)-2,4-nonadienal(fishy smell),and 3,5-diethyl-2-methylpyrazine(burnt smell)reached 171.2 and 333 respectively,imparting negative effects on flavor.In general,dried shrimp from earthen pond had a better flavor profile than those from greenhouse.

基于HS-SPME-GC-MS和化学计量学对不同产地红枣香气成分的分析

为了比较不同产地红枣的挥发性风味特征,采用顶空固相微萃取结合气相色谱质谱技术对5个产地(新郑、灵宝、榆林、和田、德州)枣果的挥发性香气成分进行分析。结果表明:共鉴定出化合物51种,其中,新疆和田大枣中所含挥发性化合物的种类最多。结合多元统计学分析,不同产地红枣的整体挥发性风味物质的差异得以很好区分。在满足预测变量重要性投影>1、P<0.05的条件下,从红枣样品中筛选出13种差异性特征香气物质,包括己酸甲酯、癸酸甲酯、己醛、苯甲醛等,赋予红枣独特的杏仁味、甜味、水果味。本研究结果明确了不同产地红枣香气品质的化学物质基础,为红枣产地溯源研究提供一种新思路,进一步对枣果资源的合理加工利用提供科学依据。

Simultaneous determination of kolliphor HS15 and miglyol 812 in microemulsion formulation by ultra-high performance liquid chromatography coupled with nano quantity analyte detector

A novel method for simultaneous determination of kolliphor HS15 and miglyol 812 in microemulsion formulation was developed using ultra-high performance liquid chromatography coupled with a nano quantitation analytical detector （UHPLC-NQAD）. All components in kolliphor HS15 and miglyo1812 were well separated on an Acquity BEH C18 column. Mobile phase A was 0.1% trifluoroacetic acid （TFA） in water and mobile phase B was acetonitrile. A gradient elution sequence was programed initially with 60% organic solvent, slowly increased to 100% within 8 min. The flow rate was 0.7 mL/min. Good linearity （r 〉 0.95） was obtained in the range of 27.6-1381.1 μg/mL for polyoxyl 15 hydroxystearate in kolliphor HS15, 0.8-202.0 μg/mL for caprylic acid triglyceride and 2.7-221.9μg/mL for capric acid triglyceride in miglyol 812. The relative standard deviations （RSD） ranged from 0.6% to 1.7% for intra-day precision and from 0.4% to 2.7% for inter-day precision. The overall recoveries （accuracy） were 99.7%-101.4% for polyoxyl 15 hydroxystearate in kolliphor HS15, 96.7%-99.6% for caprylic acid triglyceride, and 94.1%- 103.3% for capric acid triglyceride in miglyol 812. Quantification limits （QL） were determined as 27.6 μg/ mL for polyoxy115 hydroxystearate in kolliphor HS15, 0.8 μg/mL for caprylic acid triglyceride, and 2.7 μg/ mL for capric acid triglyceride in miglyol 812. No interferences were observed in the retention time ranges of kolliphor HSI5 and miglyol 812. The method was validated in terms of specificity, linearity, precision, accuracy, QL, and robustness. The proposed method has been applied to microemulsion for- mulation analyses with good recoveries （82.2%-103.4%）.

Identification and characterization of related substances in EVT-401 by hyphenated LC–MS techniques

A sensitive and selective method was developed for the separation and characterization of related substances(RSs) in EVT-401 by hyphenated LC–MS techniques. Complete separation of the RSs was achieved with an Inertsil ODS-SP column(250 mm×4.6 mm, 5 μm) by linear gradient elution using a mobile phase consisting of 0.2% formic acid solution, methanol and acetonitrile. EVT-401 was found to be susceptible to acid, alkaline and oxidative stresses, while relatively stable under photolytic and thermal dry stress conditions. Fourteen RSs including six process-related substances and eight degradation products were detected and identified in EVT-401 with positive ESI high-resolution TOF-MS analysis of their parent ions and the corresponding product mass spectra elucidation, and some of them were further verified by chemical synthesis and NMR spectroscopy. The specific LC–MS method developed for separation, identification and characterization of RSs is valuable for EVT-401 manufacturing process optimization and quality control.

Quantitative Determination of Adrenaline Hydrochloride Injection and Noradrenaline Bitartrate Injection by a New HPLC Method via Substitute for Reference Substance

An HPLC method for quantitative determination of adrenaline hydrochloride injection and noradrenaline bitartrate injection was established and validated with a substitute for the reference substance.Phenylephrine hydrochloride was selected as the substitute for the reference substance of adrenaline and noradrenaline bitartrate.The correction factor of phenylephrine hydrochloride with respect to the reference substance of adrenaline and noradrenaline bitartrate was determined under defined conditions.Adrenaline hydrochloride injection and noradrenaline bitartrate injection were quantified by assaying phenylephrine hydrochloride and a correct factor.The results indicate that the HPLC method with the substitute for reference substance was reliable and feasible for quantitative determination of drugs.