茶鲜叶中金属元素含量影响因素研究

该研究利用电感耦合等离子体质谱（inductively coupled plasma mass spectrometry,ICP-MS）对青岛市、合肥市和杭州市三地茶鲜叶中的 9 种金属元素（Na、K、Ca、Fe、Co、Cu、Zn、Mg和 Mo）含量进行检测。利用单因素方差分析、多因素方差分析和Pearson相关分析,探究产地、品种、季节及其交互作用对茶鲜叶中金属元素含量的影响,解析茶鲜叶中的金属元素含量与种源土壤中相关元素含量间的关系。结果显示：茶鲜叶中的金属元素含量在不同产地、品种和季节均具有各自的特征;除Mg、Zn和Mo外,茶鲜叶中其他金属元素的含量均与种源土壤显著相关。茶鲜叶中Na含量变异与产地×品种及产地×季节交互作用密切相关;Mg、K、Ca和Zn的含量变异与季节密切相关;Fe和Cu的含量变异与产地密切相关;Co含量变异与产地和产地×品种交互作用密切相关,而Mo含量变异与季节×品种及产地×品种×季节密切相关。研究表明,茶鲜叶中的金属元素含量变异与产地、品种、季节及其交互作用密切相关。     

二色补血草根中几种金属元素含量分析

采用微波消解-原子吸收光谱法对二色补血草根中K、Ca、Na、Mg、Zn、Fe、Cu和Mn八种金属元素含量进行了分析测定。结果表明,各元素平均回收率(n=7)在89%~96%之间能达到分析要求。八种金属元素在根中含量丰富,顺序为KNaMgCaFeZnCuMn。对金属元素含量的测定有助于阐明二色补血草的药用机理。     

奉化地区水蜜桃果实中金属元素的测定及区域分布特征评价

采用微波消解-电感耦合等离子体原子发射光谱法同时测定奉化水蜜桃（湖景蜜露和玉露）中K、Ca、Mg、Fe、Cu、Mn、Se、Zn含量,研究酸体系、金属元素谱线对测定结果的影响。在最佳实验条件下,各金属元素回收率在82.82%～118.3%之间,相对标准偏差在2.28%～18.4%之间,检出限在0.1～1 μg/L之间,满足样品检测的要求。并对浙江省奉化不同区域的湖景蜜露和玉露金属元素含量进行考察,结果表明,湖景蜜露和玉露均含有K、Ca、Mg、Fe宏量元素和Cu、Mn、Se、Zn等微量元素,且8 种元素在湖景蜜露和玉露中以及不同区域间存在差异。     

12份野生油茶籽油无机元素的分析测定

目的:建立茶油无机元素的测定方法,为制订茶油有害金属元素限量标准提供参考,同时为其健康食用和规范化栽培基地的选择提供依据。方法:用火焰原子吸收光谱法(FAAS)测定Ca、Fe、Mg、Cu、Zn和K的含量,用石墨炉原子吸收光谱法(GFAAS)测定Pb、Cd和Cr的含量。结果:12份样品中K、Ca、Mg和Fe的含量较高,有害金属元素Pb、Cd和Cr在川雅12、川雅20、川雅21中均未检测出,在其余样品中含量也较低。FAAS法测定Ca、Fe、Mg、Cu、Zn和K的回收率为99.84%~102.55%,RSD为0.55%~2.05%;GFAAS法测定Pb、Cd和Cr的回收率为99.75%~101.85%,RSD为1.87%~3.45%;各元素的相关系数为0.9990~0.9999。结论:该方法操作简便,准确性高,结果可靠,可作为茶油无机元素的定量检测方法。     

茶叶中七种金属元素的测定及成分分析

用原子吸收光谱法测定了云南省红河州5个县的茶叶中金属元素Ca、Mg、Na、Fe、Zn、Cu、Mn的含量,回收率在96.09%-102.7%之间,分析结果满意,方法简单、结果准确,同一样品处理液可以连续测定多种金属元素的含量.结果表明:不同茶叶中金属元素含量顺序为Ca>Mg>Mn>Fe(Na)>Zn>Cu.红河州茶叶中Ca、Mg、Mn、Fe、Na、Zn、Cu等人体必须的生命元素含量较高,为品质优良茶叶.     

微波消解- 火焰原子吸收法测定新疆野蔷薇果中金属元素

采用HNO3 消解体系对野蔷薇果进行程序升温微波消解制样,应用火焰原子吸收法测定野蔷薇果中的Ca、K、Mn、Zn、Mg、Fe、Cu、Na、Cr、Ni、Sr 共11 种金属元素的含量。对样品前处理条件进行筛选,确定样品适合的微波消解体系并进行消化结果的准确度和精密度实验。该方法的加标回收率为96.50%～104.50%,相对标准偏差(RSD)≤ 3.21%。结果表明,新疆野蔷薇果中富含Ca、Mg、K、Na、Mn、Fe 等对人体有益的金属元素,而Cr、Ni 等金属元素的含量较低。     

四川不同产地浓香型白酒金属元素测定及主成分分析

测定四川不同产地14种浓香型白酒中金属元素含量并结合化学计量学方法,对白酒中10种金属元素进行主成分分析,分析其中的特征元素。利用微波消解,通过FAAS和GFAAS分别测定酒中的Na、Mg、Zn、Fe、Ca和Pb、Mn、Cd、Cu含量,所得结果用SPSS 20.0进行主成分分析。结果表明,总方差82.66%的贡献来自于Na、Mg、Ca和Mn组分,其为白酒中的特征元素。     

ICP-MS对配制酒中澄清酒体和沉淀的金属元素分析

利用微波消解结合电感耦合等离子体质谱仪(ICP-MS)方法检测桑葚、山药和枸杞配制酒中澄清酒体和沉淀中K、Na、Ca、Mg、Fe、Al、Zn、Mn、Cu、Ni、Ba、Sr、Se、Co、Cr、V、Ag、Sb、Pb、As和Cd 21种金属元素含量,并对其进行线性回归分析,进一步分析澄清酒体和沉淀的差异。结果表明,澄清酒体主要金属元素是:K、Ca、Mg、Na,沉淀中主要金属元素是:K、Ca、Mg、Na、Fe、Al、Zn、Mn、Cu、Ba、Sr;线性回归分析表明澄清酒体和沉淀中的金属元素具有一致性,且在沉淀中的元素相对澄清酒体中对应的元素含量均有很大程度的上升,为解析酒体沉淀的形成提供理论依据。     

红茂草中氨基酸组分及矿物质元素含量的测定

以我国西部地区特色野生药用植物红茂草为研究对象,采用高效液相色谱仪和原子吸收分光光度计测定了红茂草中氨基酸组成和矿物质元素的含量。结果表明,红茂草中至少含有17种氨基酸,其中有7种人体必需氨基酸,种类较为齐全,氨基酸总量为花＞果＞叶＞茎＞根＞荚;对红茂草试样中的Cu、Zn、Fe、Mn、Co、Ni、Cr、Cd、As、K、Na、Ca、Mg、Li、Sr、Al、Pb、Se、Hg等19种矿物质金属元素进行了测定,发现K含量最高,Ca、Mg、Al三种含量仅次于K元素,对于单个植株K含量而言,花＞茎＞根＞叶＞豆荚＞全草＞果。     

江西名茶中10种金属元素含量的测定

对K、Ca、Na、Mg、Fe、Cu、Mn、Zn 8种必需元素火焰原子吸收光谱法的最佳工作条件(乙炔流量、空心阴极灯灯流量和燃烧器高度)进行优化,对铅、镉两种有毒元素石墨炉原子吸收光谱法的最佳工作条件(灰化温度、灰化时间、原子化温度及原子化时间)进行优化,绘制各元素的标准曲线,考察方法的检出限和精密度,优化样品前处理条件及测定样品加标回收率,并对江西名茶中对应的10种金属元素的含量进行测定比较。结果表明,建立的各元素原子吸收光谱法在相应浓度区间内线性关系良好,相关系数为0.991 8～0.999 2,精密度为0.77%～3.32%,检出限为0.004～0.050μg/mL,回收率为99.25%～102.25%,均符合要求。10种金属元素在8种茶叶中的含量差异性显著,其排序基本为KMgMnCaFeNaZnCuPbCd;遂川狗牯脑中K、Ca、Fe含量最高,庐山云雾中Na含量最高,靖安白茶中Mg、Zn含量最高,井冈山翠绿中Mn含量最高,武夷红茶中Cu含量最高,8种茶叶中Pb、Cd含量均较低。试验建立的原子吸收光谱法操作简便、干扰较少、灵敏度高,适用于各种茶叶中相应元素含量的测定;8种江西名茶中K、Ca、Na、Mg 4种常量元素和Fe、Cu、Mn、Zn 4种微量元素含量都比较丰富,Pb、Cd两种有毒元素含量均低于国家标准。     

电感耦合等离子体发射光谱法测定茶叶籽中多种元素

目的 对茶叶籽中金属元素进行分析, 为茶叶籽综合利用提供参考。方法 采用高压密闭微波消解结合电感耦合等离子体发射光谱法对茶叶籽中As、Ca、Cd、Cr、Cu、Fe、K、Mg、Mn、Na、Pb、Se及Zn等元素进行了同时快速定量分析。结果 茶叶籽中各元素含量: Mg(1652.23 mg/kg)、Ca(1 026.36 mg/kg)、Mn(122.44 mg/kg)、Na(37.77 mg/kg)、Cr(7.58 mg/kg)、Cu(9.11 mg/kg)、Fe(58.17 mg/kg)、Zn(17.59 mg/kg)、K (9191.29 mg/kg)。As、Cd、Pb及Se未检出。方法加标回收率89%~113%。结论 此方法满足茶叶籽样品中所述元素的分析要求。茶叶籽中钾、镁及钙含量较高, 钠含量相对较低; 锰、铁、锌及铬元素含量丰富。     

广东本地产茶叶矿物质元素与茶多酚含量调查分析

目的 调查广东省当地种植的茶叶矿物质元素和茶多酚含量范围、成分差异及分布特征.方法 采集2017-2018年广东省7个茶叶产区具有代表性的茶叶(绿茶、乌龙茶、红茶)样品,按照国标法对样品中的9种矿物质元素和茶多酚的含量进行测定,对比分析不同种类、不同产区中矿物质元素和茶多酚的含量差异.结果 乌龙茶中钾元素的平均含量为1...     

Comparison of mineral and trace element contents in onion cultivars (Allium cepa L.)

BACKGROUND: P, Na, K, Ca, Mg, Fe, Cu, Zn, Mn and Se were determined in five traditional onion cultivars (Allium cepa L.) from Tenerife (Guayonje, San Juan de la Rambla, Carrizal Alto, Carrizal Bajo and Masca) and a commercial cultivar (Texas Early Grano 502) grown under the same agronomic, soil and climatic conditions in order to find out differences between these cultivars. RESULTS: Carrizal Alto presented the highest K content and lowest P, Na, Fe, Zn, Mn and Se. Texas cultivar had the highest P, Mg and Se contents, and the lowest contents of Ca, Cu and Mn. There were clear differences in the mineral and trace elements contents between the two seed origins of San Juan de la Rambla cultivar. Many correlations were found between the parameters analyzed, emphasizing the Fe? Zn and Ca? Mn correlations. CONCLUSION: There were differences in the mineral and trace element composition between the onion cultivars. The environment and agronomic practices could affect the genetic information of the seeds, determining changes in the mineral and trace element composition. Linear discriminant analysis is a useful tool for differentiating onion samples according to cultivar and seed origin. Copyright © 2008 Society of Chemical Industry     

Analysis of mineral composition of some Assam and Darjeeling black teas

Black teas manufactured in Darjeeling and Assam were analysed for various macrominerals such as P, K, Ca, Mg and microminerals such as Mn, Fe and Cu. A considerable amount of minerals, eg K (40-46 mg), Mg (2.7-3.0 mg), Ca (0.48-0.66 mg) and traces of Mn (0.28-0.40 mg), Fe (0.16-0.20 mg), P (29-41 μg) and Cu (12-22 μg) were found in a cup of black tea brew. Black teas manufactured from the leaf coming from a pruned section and fine portion usually showed higher mineral content than tea manufactured from unpruned sections and coarse grade teas of Darjeeling. Assam CTC tea was found to be richer in mineral content compared to Darjeeling orthodox tea.     

扁形绿茶矿质元素含量与品质成分相关性分析

为探明扁形绿茶矿质元素含量与品质成分是否存在一定的相关性,实地采集5个产地（湖北省大悟县、浙江省磐安县、安徽省歙县、贵州省湄潭县、四川省峨眉山市）共10个代表性扁形绿茶样品,测定了9种矿质元素（Mg、K、Ca、P、Al、Mn、Fe、Zn、B）与5种品质成分（水浸出物、茶多酚、游离氨基酸、可溶性总糖、咖啡碱）含量。结果表明,扁形绿茶样品中矿质元素之间互相影响,存在协同或拮抗作用。品质成分中水浸出物含量与B含量呈显著负相关（P<0.05）,茶多酚含量与Fe含量呈极显著负相关（P<0.01）,可溶性总糖含量与B含量呈显著正相关（P<0.05）,与Mg、Ca含量则呈显著负相关（P<0.05）,Fe、Mn含量与咖啡碱存在显著负相关（P<0.05）。主成分分析结果显示前3个主成分解释累计方差贡献率为89.00%,Mg、Ca、Zn、Al、P可作为扁形绿茶的特征矿质元素,水浸出物、游离氨基酸可作为评价扁形绿茶品质的重要理化指标。聚类分析结果表明,同一产地的扁形绿茶样品聚为一类,不同产地则明显区分开,表明扁形绿茶品质存在明显的地域分布特征。     

Accumulation of Calcium in Bean Cultivars Differing in Seed Size

Accumulation of Ca, Mg and K, the principal cations in dry bean (Phaseolus vulgaris L) seed, was studied under field and greenhouse conditions. ‘Cran-09’, a cranberry bean and ‘Norstar’, a navy bean, were grown to maturity under greenhouse conditions. ‘Cran-09’ had a seed weight of 605 mg, a seed Ca concentration of 1·2 g kg^-1 and a Ca harvest index of 0·032. The corresponding three parameters in ‘Norstar’ were a seed weight of 161 mg, a seed Ca concentration of 2·2 g kg^-1 and a Ca harvest index of 0·064. The difference in seed Ca concentration was not due to increased absorption of Ca by ‘Norstar’, but rather was due to a larger proportion of Ca in plant tops being diverted to the seed component. The larger seed Ca concentration in ‘Norstar’ was compensated to some extent by a smaller seed K concentration. In contrast to Ca, cultivar had relatively little effect on harvest indices for Mg, K, N and P. The average seed Ca concentration in six navy bean cultivars grown under field conditions was 90% more than that of three kidney and three cranberry bean cultivars. © 1997 SCI.     

Effects of potassium and magnesium nutrition on the quality components of different types of tea

In field experiments, the effects of potassium and magnesium nutrition on the quality components of different types of tea, including black tea, oolong tea and green tea, were studied. The results show that K and Mg fertilizer application increased the contents of free amino acids and caffeine of the various tea types with the maximum increase found in the treatment including both nutrients. The content of polyphenols in tea leaves was also increased by K application. The effect of Mg on polyphenol content was inconsistent. In general, Mg apparently decreased the content of polyphenols and only in case the soils were depleted of plant available K and Mg, a slight increase could be observed. The contents of theaflavins and thearubigins, important quality components of brewed black tea, were also increased by K application. Flavour compounds in brewed oolong tea were considerably improved by K and Mg application. © 1999 Society of Chemical Industry     

Differentiation of eight tea (Camellia sinensis) cultivars in China by elemental fingerprint of their leaves

BACKGROUND: Tea is an infusion made from dried leaves of tea (Camellia sinensis) and can be a good dietary source of essential trace metals for humans. Therefore, it is necessary to consider variations in element content of tea leaves among tea cultivars. Thus, elemental fingerprint techniques, based on elemental contents (Al, B, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, P, Pb, and Zn) determined by inductively coupled plasma atomic emission spectrometry (ICP‐AES) and multivariate statistical analysis, have been used to differentiate eight tea cultivars. RESULTS: The ranges of element concentrations in leaves of the eight cultivars were in good agreement with those obtained in previous studies and the level of most elements in tea leaves was significantly different among cultivars. The classifications of eight tea cultivars were 100% accurate in total by principal component analysis (PCA), hierarchical cluster analysis (HCA), linear discriminant analysis (LDA), and back‐propagation neural network (BPNN) analysis. CONCLUSION: Each cultivar presented a distinctive element fingerprint and the elements in tea leaves can be significant predictors in differentiating tea cultivars. Copyright © 2009 Society of Chemical Industry     

湘式柑普茶——湘柑茶主要化学成分及挥发性成分分析

目的：湘柑茶是借鉴柑普茶的制法,采用湖南安化黑茶——天尖茶与岳阳金盆柚的柑皮制备而成的,旨在探明湘柑茶的品质。方法：对比分析了天尖茶、柑皮及湘柑茶的主要化学成分、矿质元素含量以及挥发性成分。结果：天尖茶、柑皮、湘柑茶的水分含量均＜20%,有利于贮藏。粗多糖、总黄酮、总酚含量高低顺序为天尖茶＞湘柑茶＞柑皮。天尖茶、柑皮、湘柑茶均含丰富的矿质元素,含量较高的有K、Ca、Mg、Mn。天尖茶、柑皮、湘柑茶中分别检出61,68,69种香气成分,其关键香气化合物为18~22种,天尖茶与柑皮制备成湘柑茶后检出了14种新的挥发性物质。结论：湘柑茶结合了天尖茶和柑皮的香气与营养功效,并产生了新的挥发性成分,是具有湖南地域特色的新式茶饮。     

Content of various elements in different parts of the tea plant and in infusions of black tea from Southern India

Contents of various elements in dyferent parts of the tea plant (shoot, mature leaf, small stem, thick wood and root), black tea manufactured by the crush-tear-curl and orthodox processes, and tea brew after 1 and 5 min of infusion were determined by inductively coupled plasma atomic emission spectrometry. From these, the amount of each element assimilated in the production of 1000 kg of marketable tea, as well as the quantity of each element brought into infusion and thus possib f y taken up through drinking tea, were calculated and discussed. Among the various elements assimilated by the tea plant, the shoot jraction (economically important for manufacturing commercial tea) contained high concentrations of N, P, K and Mg while the mature leaf accumulated Al, Bu, Ca, Cd, Mn, Pb and Sr. Of the dgerent elements brought into infusion while brewing black tea, the amount of K was found to be the largest (> 10000 μg g⁻¹ tea) followed by P (700–1200 μg g⁻¹), Mg (300–700 μg g⁻¹), Ca and A1 (each 150–300 μg⁻¹), Mn (60–150 μg g⁻¹), Cu, Na, Si and Z n (each 6–50 μg g⁻¹), B, Ba, Cr, Fe, Ni and Pb (each Id μg g⁻¹), and Sr, Co and Gd (each <1μg g⁻¹). The proportion of the totalamount of an element brought into infusion showed that the elements Ba, Ca, Fe and Sr were less soluble (<10 % of total amount), Al, B, Cd, Co, Cr, Cu, Mg, Mn, P, Pb, Si and Zn were moderately soluble (10–50 %), and K, Nu and Ni were highly soluble (>50%). The overall mean of the extent of solubility of all elements in 1 and 5 min showed that, out of the amount soluble in 5 min, about 68% was dissolved within 1 min.