电感耦合等离子体质谱法检测新食品原料黑果腺肋花楸果中的20种营养元素

目的：建立用电感耦合等离子体质谱(ICP-MS)法测定辽宁地区新食品原料黑果腺肋花楸果中20种营养元素(钾、钙、锰、铁、铜、锌、锶、锂、钠、镁、铝、磷、钛、钴、镍、钼、锡、锑、钡、硒)含量的方法。方法：微波消解法处理样品,采用ICP-MS法测定含量,射频功率1 500 W,采用碰撞模式,碰撞气为氦气,载气为氩气,载气流速0.7 L.min_^-1,等离子体气体流速15.0 L.min_^-1,泵速0.3r.s_^-1。结果：20种营养元素线性关系良好(r>0.9998 0)；加样回收率为89.7%～101.6%(n=6)；检测限为0.010～1.0mg.kg_^-1。结论：本方法准确可靠、灵敏简便,可用于辽宁地区新食品原料黑果腺肋花楸果中多种营养元素的质量研究,同时为测定同类新食品原料中此20种营养元素提供参考。S     

超声提取-离子色谱-脉冲积分安培检测法检测黑果腺肋花楸果中的8种单糖和双糖

目的建立超声提取-离子色谱-脉冲积分安培检测法测定黑果腺肋花楸果中的8种单糖和双糖的方法。方法采用水浸提超声提取及膜过滤法前处理黑果腺肋花楸果样品,以Dionex CarboPac PA10 Analytical Column(4 mm×250 mm)阴离子交换色谱柱为分析柱,以Dionex CarboPac PA10 Guard Column(4 mm×50 mm)为保护柱,以NaOH与CH3COONa的组合溶液作为流动相,采用梯度淋洗分离程序,脉冲积分安培方法检测。结果 8种单糖和双糖的检出限分别为5、8、3、4、7、2、5、2μg/L,且均具有较宽的线性范围(0.05～20 mg/L)。黑果腺肋花楸果中单糖和双糖测定的相对标准偏差在0.96%～6.12%之间,8种单糖和双糖的加标回收率达到90.5%～102.1%。结论本方法同时检测黑果腺肋花楸果中的单糖和双糖,其方法简便快捷、分离效果好、基体干扰少、无需衍生、灵敏度高,适用于黑果腺肋花楸果中的常见单糖和双糖组分的分析。     

黑果腺肋花楸果的活性成分、生理功能及应用

文章介绍了黑果腺肋花楸果的活性成分,重点讲述了黑果腺肋花楸果的生理功能,阐述了黑果腺肋花楸果的开发现状,并对其应用前景提出了几点建议,希望能为黑果腺肋花楸资源综合利用提供借鉴。     

解读《黑果腺肋花楸果等2种新食品原料的公告》

正一、黑果腺肋花楸果黑果腺肋花楸(Aronia melanocarpa ( Michx.)Ell.)是一种从国外引进的蔷薇科、腺肋花楸属灌木浆果果树,其果实在欧亚及北美等国家具有较长食用历史,主要被用来生产着色剂、糖浆、果汁、果酱及果酒等。我国部分地区自2005年开始引种黑果腺肋花楸,目前已在辽宁、江苏、浙江、吉林等多个省区内种植。根据《食品安全法》和《新食品原料安全性审查管理办法》,审评机构组织专家对黑果腺肋花楸果的安全性评估材     

黑果腺肋花楸功能性研究进展及其应用

黑果腺肋花楸富含原花青素、花青素、黄酮醇、酚酸等多种酚类化合物,是植物界最丰富的多酚来源之一,在生物医药以及食品保健行业都具有极高的应用价值。该文介绍黑果腺肋花楸的主要组成成分,对其功能性研究进展及应用现状进行综合论述,阐述黑果腺肋花楸的开发前景,为进一步全方位的开发黑果腺肋花楸提供更多的理论指导。     

植物乳杆菌发酵黑果腺肋花楸果汁的工艺优化

本文以黑果腺肋花楸为原料,利用植物乳杆菌C8-1对其发酵,研制具有特殊果香风味和营养价值的黑果腺肋花楸发酵饮料。采用单因素试验和正交试验对植物乳杆菌发酵黑果腺肋花楸果汁进行条件优化,以菌种接种量、发酵温度、发酵时间和料液比为影响因素,总酸含量作为指标,进行正交试验分析。结果表明,黑果腺肋花楸发酵饮料最佳发酵条件为:植物乳杆菌接种量9 lg CFU/mL,发酵温度35 ℃,发酵时间22 h,黑果腺肋花楸料液比为1:3(v:v),在此条件下,总酸含量达到6.60 mg/mL;发酵后的黑果腺肋花楸果汁中的总酚含量增加10.51%,总酸含量增加74.60%,还原糖含量降低4.41%,可溶性固形物含量降低6.15%;对色泽研究可知,发酵对黑果腺肋花楸果汁的亮度、红色色调和黄色色调均有增强作用;抗氧化实验表明,经发酵处理的黑果腺肋花楸果汁对DPPH自由基清除能力、OH自由基清除能力和总还原能力均极显著高于鲜榨的黑果腺肋花楸果汁(p<0.01)。感官评分较鲜榨果汁有明显提高。结果表明,植物乳杆菌C8-1可以在黑果腺肋花楸果汁中进行正常的生长代谢活动,并能够提高黑果腺肋花楸果汁的品质和抗氧化能力。     

黑果腺肋花楸黄酮提取工艺优化及体外抗氧化研究

应用黑果腺肋花楸作为原料,采用响应面法优化黑果腺肋花楸黄酮提取工艺,并利用V_C做对照试验,对其还原力及以及·OH、O_2~-·、DPPH自由基清除力进行研究。结果表明,最佳工艺参数为乙醇浓度77.67%、提取时间81 min、料液比1∶20(g/m L),在此条件下,黑果腺肋花楸黄酮得率5.14%。影响黑果腺肋花楸黄酮得率因素由大到小依次为乙醇浓度提取时间料液比。最佳工艺参数提取的黑果腺肋花楸黄酮对·OH、O_2~-·、DPPH自由基的IC_(50)分别为3.27、3.96、3.79 mg/m L,最大清除率达29.58%、70.23%、61.41%,并且其还原能力强,能够说明其体外抗氧化活性较强。     

大孔树脂纯化黑果腺肋花楸多酚的工艺优化

以黑果腺肋花楸为原料,采用大孔树脂纯化黑果腺肋花楸中多酚类物质。通过对比6 种大孔树脂对黑果腺肋花楸多酚吸附-解吸效果,筛选出XAD-7大孔树脂作为最佳纯化材料,并通过单因素试验确定XAD-7大孔树脂纯化黑果腺肋花楸多酚的静态吸附-解吸最佳工艺条件为：吸附时间4 h、解吸时间2 h、上样液质量浓度3.6 mg/mL、上样液pH 4、乙醇体积分数95%、乙醇溶液pH 7;其对黑果腺肋花楸多酚动态吸附-解吸最佳工艺条件为：上样流速2 mL/min、上样量560 mL、蒸馏水洗脱用量350 mL、洗脱流速2 mL/min、洗脱体积300 mL。在此条件下,黑果腺肋花楸多酚纯度由11.62%提高到64.37%,表明XAD-7大孔树脂对于黑果腺肋花楸多酚具有较好的纯化效果。     

黑果腺肋花楸多酚的抑菌活性研究

研究黑果腺肋花楸多酚对5种细菌和2种真菌的抑菌活性及其抑菌稳定性。采用双层平板打孔法,根据抑菌圈直径判断黑果腺肋花楸多酚的抑菌活性;采用比色法测定黑果腺肋花楸多酚对5种细菌的最小抑菌浓度(minimum inhibitory concentration,MIC),并以脂环酸芽孢杆菌和枯草芽孢杆菌作为指示菌,研究Na Cl浓度、温度、紫外线对黑果腺肋花楸多酚抑菌稳定性的影响。研究结果表明黑果腺肋花楸多酚对脂环酸芽孢杆菌、枯草芽孢杆菌等5种细菌均具有较好的抑菌活性,对2种真菌基本无抑菌效果。黑果腺肋花楸多酚对脂环酸芽孢杆菌(DSM 3922,AAT-92)、阴沟肠杆菌(20051)的MIC为0.40 g/L,对枯草芽孢杆菌(10034)和产气肠杆菌(10017)的MIC分别为0.05 g/L和0.10 g/L。随着Na Cl浓度的增加,黑果腺肋花楸多酚抑菌活性显著下降。多酚溶液经热处理后,抑菌活性有微弱下降趋势,经紫外线处理后抑菌活性基本无变化。     

黑果腺肋花楸酒澄清工艺条件优化

添加澄清剂结合机械过滤除去黑果腺肋花楸酒中的悬浮杂质和可能导致浑浊的胶体及其他非稳定性物质,目的是得到澄清稳定的黑果腺肋花楸酒。试验在单因素基础上采用响应面试验设计优化黑果腺肋花楸酒的澄清条件。结果显示：壳聚糖和蛋清粉复合使用澄清效果最好,添加量为壳聚糖190.00 mg/L+蛋清粉130.00 mg/L,温度11.5℃澄清67 h,可得到透明度好,透光率55.65%,宝石红色,口感柔和的黑果腺肋花楸酒。     

Speciation of organic and inorganic selenium in selenium-enriched rice by graphite furnace atomic absorption spectrometry after cloud point extraction

A new method was developed for the determination of organic and inorganic selenium in selenium-enriched rice by graphite furnace atomic absorption spectrometry detection after cloud point extraction. Effective separation of organic and inorganic selenium in selenium-enriched rice was achieved by sequentially extracting with water and cyclohexane. Under the optimised conditions, the limit of detection (LOD) was 0.08 μg L⁻¹, the relative standard deviation (RSD) was 2.1% (c = 10.0 μg L⁻¹, n = 11), and the enrichment factor for selenium was 82. Recoveries of inorganic selenium in the selenium-enriched rice samples were between 90.3% and 106.0%. The proposed method was successfully applied for the determination of organic and inorganic selenium as well as total selenium in selenium-enriched rice.     

富硒农产品中有机硒的分离与测定

目的建立富硒农产品中总有机硒的分离与测定方法。方法通过粉碎、均质、离心及环已烷萃取将富硒农产品中的有机硒与无机硒分离,分离后的试样经消解、赶酸后在最隹仪器条件下用原子荧光光谱法测定总硒和无机硒,差减法计算出总有机硒的含量。结果均质离心分离后,环已烷对水溶性有机硒的萃取率为96%,测定方法回收率为86.68%～113.48%,检出限为0.02 ng/mL,相对标准偏差(relative standard deviation,RSD)为5.14%。结论方法操作简单、无需有机硒标准品、检测周期短、样品普适性强,适用于初级农产品、加工农产品、保健品、发酵产品等4类富硒农产品的中总有机硒的测定。     

Speciation Determination of Selenium in Seafood by High-Performance Ion-Exchange Chromatography-Hydride Generation-Atomic Fluorescence Spectrometry

A high-performance ion-exchange chromatography coupled with hydride generation-atomic fluorescence spectrometry (HPIEC-HG-AFS) method was developed for simultaneous speciation of selenium in seafood. Three selenium species including of selenocystine (Se-Cys), selenome-thionine (Se-Met), and selenite Se(IV) were separated on an anion-exchange column (PRP-X100) with eluent of 30 mM NH₄H₂PO₄ and methanol (39:1, v/v) in 10 min at the flow rate of 1.0 mL min^?1. Variables affecting the HG-AFS detection of selenium species were optimized. The optimum conditions found were the following: reducing agent, 2.0 % of KBH₄, and 5.0 % of HCl; lamp current, 90 mA; photomultiplier tube voltage, 280 V; flow rate of carrier gas, 300 mL min^?1; and shielding gas, 800 mL min^?1. Under the optimized conditions, the good linearity of calibration curves (R ²?>?0.999) between signal of fluorescence and concentration of selenium species was obtained in the range of detection limits (DLs), 80 μg L^?1, and the DLs of Se-Cys, Se-Met, Se(IV) were 1.66, 0.990, 1.10 μg L^?1, respectively. The repeatability of the method, expressed as relative standard deviation, was less than 5.0 % (n?=?10), and the average recoveries for spiked test were from 87.3 to 103 % for three analytes in real seafood samples. The developed HPIEC-HG-AFS method was successfully applied for the speciation of selenium in seafood samples.     

Determination of selenium in garlic by cathodic stripping voltammetry

The selenium content in a garlic sample was determined on hanging mercury drop electrode (HMDE) using cathodic stripping voltammetry (CSV). In this method the dried garlic sample was digested in HNO₃:HClO₄ (1:1) by wet-digestion procedure. The CSV voltammogram in 0.1 M HCl solution showed a peak for Se at −0.56 V. Effect of deposition potential, deposition time and sweep rate on this peak were tried to determine the optimum experimental conditions. A deposition potential of −0.2 V was applied for 120 s while stirring the solution by passing nitrogen and followed a potential scan of 50 mV/s in a negative direction. The standard addition method was used to determine selenium in the sample. The linear domain range of Se (IV) was 2.0×10⁻⁸–6.0×10⁻⁷ M with a correlation coefficient of 0.9985. This method was used for the first time for the determination of selenium in garlic sample without any separation procedure and preconcentration techniques such as ion exchange, solvent extraction or hydride generation. The amount of selenium determined in three different samples from three different regions were 370±26 (n=5), 485±35 (n=4) and 365±46 (n=4) ng/g (dry-weight) with relative standard deviations of 7.0, 7.2 and 12.6%, respectively.     

Ultrasound assisted-hollow fibre liquid-phase microextraction for the determination of selenium in vegetable and fruit samples by using GF-AAS

A rapid, simple and sensitive cleanup procedure is demonstrated for the determination of selenium in vegetable and fruit samples by using ultrasound assisted-hollow fibre-liquid microextraction (UA-HF-LPME) and graphite furnace atomic-absorption spectrometry (GF-AAS). Method is based on the microextraction of selenium from sample solution into 3.5 μL of organic solvent containing an N-octyl acetamide (OAA) as an extracting agent, which is placed inside the hollow fibre followed by ultrasound irradiation. The parameters that affected the extraction efficiency of selenium from sample solution were investigated. The best optimum conditions for the extraction of selenium were achieved for 15 min of extraction time with 500 rpm of agitation rate at the pH range of 0.8–3.0. The optimised methodology exhibited good linearity between 0.2 and 5 ng mL⁻¹ selenium with relative standard deviations (RSD) from 2.5% to 4.4%. The proposed method has been successfully applied for the determination of selenium from different types of vegetable and fruit samples. The potentiality of the present (UA-HF-LPME) method was compared with ultrasound assisted-single drop microextraction (UA-SDME). Thus, this approach proves that the UA-HF-LPME technique can be applied as a simple, fast and feasible diagnosis tool for the analysis of selenium in vegetable and fruit samples.     

Determination of Ethyl Carbamate in Sake Using Headspace Solid Phase Microextraction

An analytical method for the determination of ethyl carbamate in alcoholic beverages has been developed and optimized. A combination of headspace solid phase microextraction (HS‐SPME), as the extraction technique, and GC/MS, as the determination technique, was utilized. Analytical grade ethyl carbamate dissolved in ethanol solution was analyzed to determine the optimum analytical conditions. Ethyl carbamate‐d₅ was added as an internal standard. The following HS‐SPME conditions were investigated: type of stationary phase of the fibre, ethanol content, sample volume and extraction time. The optimized procedure showed that the detection limit, relative standard deviation, and recovery were 6.7 μg/L, 0.4–2.0%, and 103.6–107.6%, respectively. The precision of this new method was equivalent to previous analyses. Finally, the developed method was applied to the analysis of ethyl carbamate in sake.     

Separation and determination of amygdalin and unnatural neoamygdalin in natural food supplements by HPLC-DAD

ABSTRACT

This work is focused on separation and determination of amygdalin and its unnatural form neoamygdalin in natural food supplements. Reversed-phase high-performance liquid chromatography with a high-stability silica-based column with C₁₈ functional group has been used for solving this problem. The effect of the mobile phase composition as well as the column temperature on the separation of the amygdalin epimers has been investigated. Isocratic elution using a mobile phase composed of 0.05% aqueous formic acid and acetonitrile achieved the required separation within 17 min. Under optimum chromatographic conditions, the developed method was validated and was applied for the determination of amygdalin epimers in natural food supplements containing apricot or peach kernels. A simple extraction method using methanol as an extractant supported by an ultrasonic bath was used with recovery in the range of 94.8% to 104.3%. The limit of detection and limit of quantification values for R-amygdalin were 0.13 mg/L and 0.40 mg/L, respectively. The developed method proved to be precise with the intra-day and inter-day relative standard deviation values less than 2.23%.     

Automated Single-Phase Liquid-Liquid Extraction for Determination of Cr(VI) Using Graphite Furnace Atomic Absorption Spectrophotometry without Wet Digestion of Samples

This paper proposes a method to perform rapid and sensitive graphite furnace atomic absorption spectrometry (GFAAS) determination of Cr(VI) in vinegar samples without wet digestion. Taking into account low levels of Cr(VI) and the presence of several concomitants in the sample matrix, the proposed method uses single-phase liquid-liquid extraction (SPLLE). The method is automated, employing a flow-batch analyzer (FBA) which uses a mixing chamber designed to emulate a separation funnel promoting the formation/break of the single-phase solution, reaction and extraction. The Cr(VI) extraction procedure was performed by proportioned mixing of the vinegar sample (aqueous phase), amyl alcohol (organic phase), and ethanol (consolute) to form a single-phase solution. The chelating reagent sodium diethyldithiocarbamate (DDTC) dissolved in the consolute reacts rapidly with Cr(VI), in the single phase to produce a stable Cr-DDTC complex. The single-phase break step is performed by adding an excess of Britton-Robinson buffer, and then the organic phase enriched with Cr(VI) was analyzed by GFAAS. Factors such as extraction steps, single-phase composition, pH, chelating agent concentration, and flow-batch parameters were optimized. The FBA-SPLLE-GFAAS was evaluated in vinegar samples showing satisfactory analytical features in terms of limit of quantification (0.86 μg L ^?1 ), precision (RSD <12 %), characteristic mass (m₀ = 0.32 pg), high sampling rate (26 h ^?1 ), and accuracy (recovery rate = 82–108 %). The proposed method requires one-step extraction and is eco-friendly since it consumes low amounts of non-toxic chemicals and generates little waste (about 700 μL per determination).     

A New and Fast HPLC Method for Determination of Rutin, Troxerutin, Diosmin and Hesperidin in Food Supplements Using Fused-Core Column Technology

A new and fast high-performance liquid chromatography (HPLC) method using fused-core column for separation of rutin, troxerutin, diosmin, and hesperidin has been developed and used for determination of these flavonoids in food supplements. Efficient separation of flavonoids and internal standard methylparaben was achieved on the fused-core column Ascentis Express RP-Amide (100?×?3.0 mm), particle size 2.7 μm, with mobile phase acetonitrile/water solution of acetic acid pH?3 (30:70, v/v) at a flow rate of 1.0 mL?min^?1 and at temperature 50 °C. The detection wavelengths were set at 283 nm for hesperidin and at 255 nm for rutin, troxerutin, diosmin, and internal standard methylparaben. Under the optimal chromatographic conditions, good linearity with correlation coefficients in the range (r?=?0.9991–0.9998; n?=?7) for all flavonoids was achieved. Commercial samples of food supplements were extracted with 100 % dimethyl sulfoxide using ultrasound bath for 10 min and then diluted to methanol. A 5-μL sample volume of the filtered solution was directly injected into the HPLC system. Accuracy of the method defined as a mean recovery of flavonoids from food supplement matrix was in the range 96.2–104.4 % for all flavonoids. The intraday method precision was satisfactory, and relative standard deviations of sample analysis including preparation and determination of different food supplements were in the range 0.5–3.5 % for all flavonoids. The developed method has shown high sample throughput during sample preparation process, modern separation approach, and short time (5 min) of analysis.     

Cloud Point Extraction-Inductively Coupled Plasma Mass Spectrometry for Separation/Analysis of Aqueous-Exchangeable and Unaqueous-Exchangeable Selenium in Tea Samples

A simple method based on cloud point extraction (CPE) separation and inductively coupled plasma mass spectrometry (ICP-MS) detection was proposed for the determination of species of aqueous-exchangeable selenium and unaqueous-exchangeable selenium. When the system temperature is higher than the cloud point extraction temperature (CPT) of the surfactant of p-octyl polyethyleneglycolphenyl ether (Triton X-100), the complex of selenium(IV)–diethyl-dithiocarbamate (DDTC) (total selenium and aqueous-exchangeable selenium) could be extracted into the surfactant-rich phase, an in situ separation of selenium(IV) could be realized. Unaqueous-exchangeable selenium concentration was obtained by respectively subtracting aqueous-exchangeable selenium from the total selenium. The chemical variables affecting the CPE were optimized. Under the optimized conditions, the limit of detection (LOD) and the relative standard deviations (RSD) was 0.10 ng/mL and 3.2% (c?=?10.0 ng/mL, n?=?11), respectively, for Se(IV). The proposed method was applied to the speciation of aqueous-exchangeable and unaqueous-exchangeable selenium in tea samples with satisfactory results.