微波消解- 火焰原子吸收光谱法测定蜂胶中金属元素含量

目的:测定一种原产地为加拿大的蜂胶中金属元素的含量,为进一步研究蜂胶营养价值提供数据,同时改进测量方法。方法:用微波消解法处理样品,用硝酸和过氧化氢的混合物作为消解剂进行微波消解,并优化消解条件,然后用火焰原子吸收光谱法测定蜂胶制品中钙、铁、镁、锌、钠、钾、铜的含量。结果:七种元素相对标准偏差为0.85%~2.33%(n=7),回收率在96.5%~104.7%之间。试验结果表明该蜂胶中含有丰富的金属元素,且与河南产蜂胶相比,加拿大产蜂胶中多种金属元素含量远低于河南产蜂胶。结论:使用本文方法测定蜂胶中的金属元素含量,结果准确,方法可靠。为进一步探讨蜂胶制品金属元素与其保健功能的关系提供了有用数据。     

微波消解-石墨炉原子吸收光谱法测定大鼠组织中的微量硒

目的:建立微波消解石墨炉原子吸收光谱法(GFAAS)测定大鼠组织中的微量硒的检测方法.方法:采用微波消解法处理样品,用硝酸作为消解剂进行微波消解;采用氯化钯则作为基体改进剂来测定样品中的微量硒.结果:最佳灰化温度为900℃,原子化温度为2500℃;脑组织和肺组织的相对标准偏差(RSD)分别为2.83％和3.05％,样品加标回收率为97％～105％.结论:该方法用于检测大鼠组织中的硒含量,操作简便、快速、准确度好、结果满意,能够适用于生物体内多种组织器官中硒含量的测定与分析.     

微波消解-火焰原子吸收法测定中药双柏散中六种金属元素的含量

双柏散合剂因其具有清热解毒、活血化瘀、止痛消肿等功效而广泛应用于软组织损伤及各种疼痛的治疗。为了研究该药物中无机金属元素的含量,本实验以浓硝酸为消解试剂,对双柏散样品进行高压密闭微波消解,后将消解液小心赶酸后用1%的硝酸溶液定容配。配制系列标准溶液,采用火焰原子吸收分光光度计及标准曲线法测定双柏散原料药中Fe、Mg、Cu、Ca、Mn、Zn 6种金属元素的含量。结果表明双柏散合剂中均含有上述6种金属元素,Fe、Ca、Mg、Mn、Cu、Zn含量分别为321.9μg/g、7 248.0μg/g、1 481.3μg/g、79.9μg/g、7.9μg/g、40.1μg/g,双柏散中钙和镁的含量最高,其它各种测定的金属元素均有一定的含量。本实验方法简单、准确,对于其它样品中金属元素的测定具有推广意义。     

微波消解技术在环境化学分析中的应用

微波消解技术在环境中应用广泛得益于我国微波消解技术的迅速发展。在环境化学分析中的样品存在有毒有害成分屡见不鲜,利用微波消解的快速、准确、重复性好等优点可以解决传统消解方法耗时长和污染大这一问题。分析微波消解原理及特性,叙述了环境分析中微波消解技术的概况应用,其主要分为COD、金属元素,非金属元素与有机物测定的预处理还有含水率的测定,在此基础上对未来的发展趋势作出了全新的规划与展望。     

微波消解-FAAS法测定普通甘薯和紫甘薯中的金属元素

采用微波消解法处理普通甘薯和紫甘薯样品,运用火焰原子吸收光谱法测定其中的K、Ca、Mg、Fe、Mn、Zn、Cu 7种对人体有益的金属元素含量。结果表明,普通甘薯和紫甘薯中K、Ca、Fe、Mg元素含量较高,Mn、Zn、Cu元素含量较低,且7种金属元素含量在两者之间存在一定的差异,各元素在紫甘薯中的含量均比普通甘薯中含量高。方法的加标回收率介于98.5%～103.2%,相对标准偏差(RSD)不大于3.14%。可为普通甘薯与紫甘薯的品质评价提供理论参考。     

红景天根中总黄酮和多糖的微波提取及含量分析

目的;从红景天中提取有效成分总黄酮,多糖,并测定其含量。方法：分光光度法,结果：测得红景天总黄酮含量4．62％,平均回收率为98．59％,RSD1．23（n=3),多糖含量9．12％,平均回收率为99．25％,RSD1．12％（n=3)。结论：运用微波技术辅助测定红景天中总黄酮和多糖的含量,反应速度加快,收率提高。     

微波消解-ICP-MS法测定油菜蜂花粉咀嚼片中12种元素

采用微波消解法处理样品,研究了微波消解和ICP-MS的测定条件,测定了咀嚼片中Cr、Mn、CA、As、Sn、Ni、Zn、Co、Ag、Pb、Se、Te12种元素含量,在最佳实验条件下,方法测定下限介于0．01μg/g-0．10μg／g之间,RSD均小于5％,加标回收在97—103％之间,方法可用于实际样品分析。     

ICP-OES测定铁皮石斛干花中多种元素

用微波消解和马弗炉灰化消解分别处理云南、浙江、霍山三种产地的铁皮石斛干花,再用电感耦合等离子体发射光谱仪(ICP-OES)定量分析多种元素含量,构建一种快速测定石斛干花元素含量的方法。结果表明,微波消解结合ICP-OES测出三产地石斛花存在常量元素K、Ca、Na、Mg和微量元素Se、Co、Cu、Mn、Fe、Cr、Sr、Zn、B,且含量均高于马弗炉消解结合ICP-OES测定结果;有害元素As、Pb、Cd、Hg和潜在有害元素Sb、Ba、Sn、Al、Ni均未检出;内标回收率均在92.5%-110.0%之间,相对标准偏差(RSD)<10%。试验探究出微波消解和ICP-OES的结合不仅效率高,检测成本低,运行稳定且测定结果准确可靠,可用于铁皮石斛干花中多元素分析研究。     

气相色谱法测定人白蛋白制品中辛酸钠含量

本文报导用气相色谱法测定人白蛋白制品中辛酸钠含量。样品用正庚酸作内标,经酸化、氯仿抽提、浓缩后,通过ＨＰ－ＩＮＮＯＷａｘ柱,以氢火焰检测器测定。本法色谱峰形好,平均回收率及变异系数分别为９８．５４％、１．３９％。测定线性范围在１０７μｇ／０．２５ｍｌ～７２０μｇ／０．２５ｍｌ。最小检测限为７．４１０μｇ。实验操作简便,样品及溶剂用量少,可作为人白蛋白制品中辛酸钠含量的检测方法。     

恒河猴血清孕酮含量测定方法

目的建立恒河猴血清中孕酮含量测定方法。方法本文采用放射免疫测定技术。结果孕酮的回收率为94％,批内CV为5．1％～8．3％,批间CV为4．5％～7．7％,灵敏度为5～10Pg。说明该方法具有较高的灵敏度、特异性、准确性。分别测定了幼年组、成年组和老年组的雌性恒河猴的血清中的孕酮含量分别为：（0．20±0．04）ng／mL、（6．26±0．17）ng,mL和（0．35±0．06）ng/mL;成年雌性恒河猴月经周期孕酮的变化范围为：滤泡期为（1．10±0．12）ng／mL,排卵期（2．36±0．18）ng/mL,黄体期（6．17±0．15）ng/mL,妊娠期随着妊娠月份的增加,孕酮浓度也增加,最高可达50ng／mL。结论经实验验证,该方法灵敏、可靠、适用,可作为恒河猴血清中孕酮含量测定的一种方法。     

Phytochemicals,mineral contents,antioxidants, and antimicrobial activities of propolis produced by Brunei stingless bees Geniotrigona thoracica,Heterotrigona itama,and Tetrigona binghami

The present study focused on the evaluation of phytochemical properties, essential mineral elements, and heavy metals contained in raw propolis produced by stingless bees Geniotrigona thoracica, Heterotrigona itama, and Tetrigona binghami found in the same ecological conditions and environment in Brunei Darussalam. The results indicated that propolis of the three stingless bee species mainly consisted of lipids (45.60–47.86%) and very low carbohydrate (0.17–0.48%) and protein contents (0.18–1.18%). The propolis was rich in mineral elements, thus good sources of minerals, while they contained low concentrations of all heavy metals. Propolis of the different bee species could be distinguished based on their mineral compositions. The vibrational and absorption spectra suggested that propolis contains π-conjugated aliphatic and aromatic compounds as well as aromatic acids having amine, ester, carbonyl, alkyl, and hydroxyl functional groups which might be attributed to the presence of phenolic and flavonoid compounds. The antioxidant capacity of the propolis, based on radical scavenging activity of their ethanol extract, was in line with their total phenolic content. The ethanol extract of the propolis also showed antimicrobial activities against four bacterial strains (Bacillus subtilis, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa). The propolis showed slightly higher antibacterial activity against Gram-positive (B. subtilis and S. aureus) bacteria, indicating that the antimicrobial active compounds could be associated with flavonoids, which were quantified to be approximately comparable in all the propolis.     

Simultaneous sewage sludge digestion and metal leaching — effect of temperature

The effect of temperature on the simultaneous sewage sludge digestion and metal leaching process was studied in laboratory bioreactors of 20 l working volume. The results thus obtained showed that the process can be employed efficiently for metal solubilization, elimination of indicator microorganisms and sewage sludge stabilization at temperatures between 10°C and 30°C. Rates of pH reduction, sulfur oxidation, growth of thiobacilli, elimination of indicator microorganisms and solids degradation were found to decrease with temperature. Low metal solubilization efficiency was observed at 10°C; however, metals were solubilized to below the recommended level. The solubilization of organic matter and nutritive elements (N, P and K) was not significantly affected by the variation in temperature. The fertilizer value of sludge after leaching and digestion did not change significantly and remained the same irrespective of temperature. *** DIRECT SUPPORT *** AG903078 00005     

Toxic Element Profiles in Selected Medicinal Plants Growing on Serpentines in Bulgaria

Populations of medicinal plants growing on serpentines and their respective soils were analyzed for Fe, Ni, Mn, Cr, Co, Cd, Cu, Zn, and Pb using inductively coupled plasma atomic emission spectrometry. Aqua regia extraction and 0.43 M acetic acid extraction were used for the quantification of pseudototal and bioavailable fractions, respectively, of elements in soil and nitric acid digestion for determination of total element content in plants. Screening was performed to (1) document levels of toxic metals in herbs extensively used in preparation of products and standardized extracts, (2) compare accumulation abilities of ferns and seed plants, and (3) estimate correlations between metal content in plants and their soils. The toxic element content of plants varied from site to site on a large scale. The concentrations of Fe and Ni were elevated while those of Cu, Zn, and Pb were close to average values usually found in plants. The highest concentrations for almost all elements were measured in both Teucrium species. Specific differences in metal accumulation between ferns and seed plants were not recorded. The investigated species are not hyperaccumulators but can accumulate toxic elements, in some cases exceeding permissible levels proposed by the World Health Organization and European Pharmacopoeia. The harvesting of medicinal plants from serpentines could be hazardous to humans.     

Pollution,source, and ecological risk assessment of trace elements in surface sediments of Lake Aktaş, NE Turkey

This study applies ecological indices to determine the anthropogenic-based metal enrichment and potential ecological and ecotoxicological risks posed by each metal in the sediments of Lake Akta?, NE Turkey. Sediment samples were collected from nine stations (St1–St9) within the Turkish boundary of Lake Akta? and the heavy metal, total organic carbon %, CaCO₃%, chlorophyll degradation products (chlorophyll-α), total sulfur %, and total phosphate % contents in the sediment samples were determined. Enrichment factor (EF), pollution load and potential ecological risk (PER) indices were calculated to shed light on the ecological effects of heavy metals. The metal content was ranked in descending order of Al > Fe > Mn > Zn > Ni > Cr > Cu > Pb > As > Cd > Hg. The EF values ranged 0.87–1.0 for Cu, 1.04–1.14 for Pb, 1–1.08 for Zn, 0.88–0.95 for Ni, 0.99–1.24 for Mn, 0.89–0.93 for Fe, 0.82–1.01 for As, 0.96–1.19 for Cd, 0.94–1.0 for Cr, and 1.42–1.90 for Hg. Minimal contamination was found for Hg. Pollution load, PER, and toxic risk indices indicated no ecological risk currently. However, considering the PER index for metals individually, a moderate potential risk was detected for Hg. The data obtained from multivariate statistical analyses indicate that Hg and Mn originate from the atmosphere, while other elements have lithogenic sources.     

In-vitro antioxidant,in-vivo anti-inflammatory,and acute toxicity study of Indonesian propolis capsule from Tetragonula sapiens

Propolis is widely used as traditional medicine since ancient times. It was necessary to conduct the pre-clinical study because of its relevant curative properties. This study aimed to investigate in-vitro antioxidant, standardize quality parameters, study acute toxicity, and determine in-vivo anti-inflammatory. Three spectrophotometric methods were used to determine antioxidant activity. The standardization includes physical, chemical, and microbiological evaluation. Furthermore, an acute toxicity test was conducted using 20 female Sprague Dawley (SD) strain rats divided into 4 groups with different dose of propolis. The in vivo anti-inflammatory test was carried out using the carrageenan induction method on rats' soles. A total of 36 female SD rats were classified into 6 groups as follows, Group normal, negative control, diclofenac sodium, and three propolis groups (72; 144; and 288 mg/kg BW). The results demonstrated the IC₅₀ values of the DPPH and ABTS scavenging activity 9.694 ppm and 2.213 ppm, respectively. The FRAP reducing power was 189.05 mg AaE/g. The physical appearance of propolis capsule was vegicaps as white – white, size 0, with light brown granule. Moreover, the content weight was 418.88 mg with a disintegration time of 7 min 53 s, while the water, flavonoid, and polyphenol contents were 9.07%, 1.59%, and 98.0821 mg GAE/g respectively. The content of heavy metal and microbial contamination were not detected. The acute toxicity results showed LD₅₀ ≥ 5 g/kg BW, no toxicity symptoms, and no abnormalities in all rats. The anti-inflammatory inhibition percentage for groups III, IV, V, and VI was 11.86%, 6.53%, 7.81%, and 6.63% respectively, while the anti-inflammatory drugs effectiveness percentage compared to positive controls were 55.00%, 65.83%, and 55.83% respectively. Based on these results, it can be concluded that propolis capsules fulfilled the standardization requirements, and it is likely to be non-toxic, and effective as antioxidant and anti-inflammatory.     

The first insight into the trace element status of human adrenal gland accompanied by elemental alterations in adrenal adenomas

BackgroundThe baseline status of trace metals in adrenal tissue is unresolved, while the elemental profile for any adrenal pathology has not been examined so far. This study aimed to determine the baseline status of important toxic (Ni, As, Cd, Pb, Th, U) and essential trace elements (Mn, Co, Cu, Zn, Se) in healthy adrenal tissues (HATs) as well as to examine whether there are alterations in the elemental composition of adenomatous adrenal tissues (AATs). Furthermore, this study aimed to find potential trace metals that could play a role in the pathogenesis of adrenal adenoma (AA).MethodsThe study included 45 patients diagnosed with AA. Impacts of relevant parameters such as gender, age, smoking habits and nodular sizes were considered. All samples were subjected to microwave digestion and the trace elements were determined by inductively coupled plasma mass spectrometry (ICP-MS).ResultsThis is the first study that provided an insight into the elemental status of HATs. It was also shown that AATs had altered trace metal contents. Compared to HATs, the most significant findings were related to the high content of essential (Cu, Mn, Se, Zn) and Pb as a non-essential metal. Although gender, age and smoking habits had a modest effect on metal profiles, the most significant alterations were related to the nodular diameter above 4 cm, indicating that the growth of benign tumor could influence changes in elemental composition.ConclusionFor the first time the baseline contents of essential and toxic trace metals in HATs were determined. The results of this study may highlight the role of toxic and essential trace metals in AAs and could provide new insights into the molecular basis of pathophysiological changes caused by the hazardous effects of trace metals on adrenal structure and function.     

Fate ofescherichia coli andE. coli O157∶H7 in apple juice treated with propolis extract

Fruit juices are targets of spoilage moulds, yeasts and acid tolerant bacteria. They might be contaminated with bacteria from raw materials, environment, packaging and during the handling of the product. These contaminations have frequently resulted in the spoilage of fruit juice and consequently commercial losses. The objective of this study was to determine the influence of propolis in apple juice againstEscherichia coli andE. coli O157:H7 strains of the spoilage and pathogenic bacteria. For this purpose, apple juice was obtained from fresh apples and then was pasteurised. The pH value, titrable acidity (as % malic acid) and Brix degree of this apple juice were 3.72±0.10, 0.67±0.05% and 12.1±0.01, respectively. Propolis extract at 1,2 and 5% concentrations were tested to determine ofE. coli andE. coli O157:H7 inhibition using paper disc diffusion method. The control treatment had no propolis extract. The apple juices were contaminated with these bacteria, and the activity of propolis was observed at first, 18^th, 24^th, 48^th and 72^nd hours at 4 and 25°C. The number of cells in the tubes was counted using serial dilution method. Results indicated that propolis extract at 2 and 5% concentrations had significant antimicrobial activity againstE. coli andE. coli O157:H7, therefore we can conclude that propolis extract is worthy of further study as a natural preservative for the foods prone to microbial spoilage.     

Advances of organic products over conventional productions with respect to nutritional quality and food security

Organic products are derived from the organic production system, following organic agricultural cultivation standards, and processing schedules must be identified by an independent certificate authority. The main characteristic of the organic agricultural production system is that all artificial synthetic materials such as pesticides, fertilizers, growth regulators, feed additives, and gene engineering products are not allowed to use. However, there is much debate on organic production quality and health safety issues in academic circles. Some people believe that there is a “Three Cannot” problem with organic production, that is, organic products “cannot be distinguished, cannot be tasted and cannot be measured” compared to common ones. To objectively reflect the differences in nutritional quality and food safety between organic and conventional products, we combined extensive literatures with our research data and have reported some advances in the sensory quality, nutritional value, and safety of the two types of products. The results showed that organic products tasted better; the percentage of leanness was higher, and the products tasted much tender. The dry matter content of most organic crops was about 7–20% higher than that of conventional foods, and enriched vitamin C, anthocyanins, isoflavones, carotenoids, and other phenolic compounds and more elements such as P, Fe, and Mg and trace elements such as Zn, Cu, and Cr were verified in organic crops. Organic animal products contain more beneficial polyunsaturated fatty acids; the nitrate content in organic fruits and vegetables was 20–50% of that in normal fruits. No pesticide residues and less heavy metals were found in the organic products. Our investigation showed that there were obvious differences in quality and safety between the products that originated from organic agriculture systems and conventional alternatives. This conclusion can provide an important theoretical basis for the healthy development of the organic industry.     

6种交通重金属污染物在悬铃木叶、枝条组织中的分布研究

以南京市常见行道树二球悬铃木为试材,通过对交通繁忙区和相对清洁区道路两边悬铃木叶和一年生枝条中6种重金属元素在组织水平分布的研究,揭示其在悬铃木各组织中可能的分布机理,以及对重金属可能的抵御机制。结果表明,置于空气污染下悬铃木叶片与一年生枝条各组织具有累积重金属元素的能力,且污染区相对含量高于清洁区（除Ni外）;叶片各组织累积能力大小为下表皮＞上表皮、海绵组织＞栅栏组织。悬铃木一年生枝条表皮因具有皮孔、表皮毛和蜡质,故也有一定的重金属累积能力;悬铃木表皮系统是重要的重金属吸滞组织,且累积于表皮的重金属元素可通过表皮进入皮层和髓,这与一年生枝条内重金属元素的运输途径有关,具体运输机理有待于进一步探讨。根据悬铃木各组织重金属的分布,认为叶片和茎的表皮系统更能反映空气污染的真实情况,且这两种材料采集容易、破坏性小,建议在空气污染监测中大力采用。