不同产地川佛手中重金属含量测定及安全性评价

建立川佛手重金属含量测定的电感耦合等离子体发射光谱（ICP-OES）分析方法,并对川佛手重金属含量进行分析与安全评价。样品经微波消解后,用 ICP-OES 方法测定其铅、镉、铜、汞、砷 5 种重金属含量。利用 SPSS 统计软件对不同重金属元素进行相关分析和聚类分析,结合单因子污染指数法和 Nemerow 综合污染指数法评价其安全性。结果表明,铅、镉和铜的线性范围为 0~1.00 μg/mL,砷和汞的线性范围为 0~0.10 μg/mL,线性关系良好（r>0.998 6）,检测限范围为 0.000 3~0.004 5 μg/mL,精密度实验 RSD 为 1.03%~4.39%,重复性实验 RSD<5.00%,平均加样回收率在94%~101%。建立的 ICP-OES 方法可准确测定川佛手中 5 种重金属元素的含量。铅、镉、铜的平均含量分别为 2.035、0.121、3.237 μg/g,汞、砷均未检出。铅-镉、铜-镉之间存在负相关,铅-铜之间存在正相关。30 个不同产地川佛手样品中重金属含量均在中国《药用植物及制剂进出口绿色行业标准》规定范围内,综合污染指数为 0.316~0.518,处于安全水平。     

原子荧光光谱法对红景天制剂中砷、汞含量的检测

目的建立红景天制剂中砷、汞含量的测定方法。方法以HNO_3-H_2O_2为消解剂对试样进行微波消解,用原子荧光光度计对样品进行测定。结果砷、汞的线性范围分别为0～10μg/L、0～1.0μg/L,线性方程分别为IF=241.67981c-21.74423(R=0.99987)、IF=1322.4766c-8.1358(R=0.99982)。在红景天膏剂、片剂和颗粒中的砷含量分别为0.362、0.280、0.210 mg/kg,汞含量分别为0.17、0.022、0.031 mg/kg。砷、汞检出限分别为0.02、0.01μg/L,平均回收率分别为4.31%～101.09%、 93.45%～102.62%(n=5)。结论该方法操作简便,结果准确可靠。     

不同产地川佛手中重金属含量测定及安全性评价

建立川佛手重金属含量测定的电感耦合等离子体发射光谱（ICP-OES）分析方法,并对川佛手重金属含量进 行分析与安全评价。样品经微波消解后,用 ICP-OES 方法测定其铅、镉、铜、汞、砷 5 种重金属含量。利用 SPSS 统 计软件对不同重金属元素进行相关分析和聚类分析,结合单因子污染指数法和 Nemerow 综合污染指数法评价其安全性。 结果表明,铅、镉和铜的线性范围为 0~1.00 μg/mL,砷和汞的线性范围为 0~0.10 μg/mL,线性关系良好（r>0.998 6）, 检测限范围为 0.000 3~0.004 5 μg/mL,精密度实验 RSD 为 1.03%~4.39%,重复性实验 RSD     

压力罐一次消解、原子荧光法同步测定甘蔗汁中砷和汞含量

在甘蔗汁中加入硝酸和过氧化氢使用压力罐一次消解、原子荧光光度计同时测定砷和汞含量,本方法汞的检测结果回收率达到88.50%~93.90%,砷的回收率达100.35%~107.80%。利用此方法检测甘蔗汁中汞和砷含量准确可靠,且该方法节约时间,降低对工作人员健康伤害和空气污染。     

不同消化方法-电感耦合等离子体质谱法测定红茶中15种金属元素的比较

本试验分别采用干法灰化法、湿法消解法、微波消解法3种不同的消化方法作为前处理方式,用电感耦合等离子体质谱法(ICP-MS)测定红茶中15种金属元素。试验结果表明:干法灰化法处理测定的金属元素含量高于湿法消解法,而微波消解法处理测定的含量高于干法消解法。采用内标法,对各个元素的检出限、线性范围、3种前处理基本参数进行了研究,并进行了标准物质测定和精密度试验。选用微波消解法处理样品,标准物质测定值更接近标准参考值,相对标准偏差<2%,干灰化法优于湿法消解法,相对标准偏差分别为2%~3%、3%~5%。微波消解前处理方式明显优于其他两种前处理方法,简便、快速、准确率高,适用于多种金属元素的同时测定。     

石墨消解-电感耦合等离子体质谱法测定烟叶中12种微量元素

采用石墨消解-电感耦合等离子体质谱法(ICP-MS)同时测定烟叶中硼(B)、钛(Ti)、铬(Cr)、锰(Mn)、镍(Ni)、铜(Cu)、砷(As)、硒(Se)、钼(Mo)、镉(Cd)、铯(Cs)、钡(Ba)12种微量元素。样品的前处理采用硝酸和过氧化氢混合溶液,通过石墨消解仪进行消解,建立了一种新的前处理消解方法。用此检测体系对来自湖南湘西3个地区的烟叶样品进行了测定,研究并发现了以上微量元素随产地、部位的不同而在烟叶中存在一定的含量差异。该方法相对标准偏差:1.25%~8.93%,回收率:93.07%~104.75%,适用于烟叶中多种微量元素含量的测定。     

微波消解-电感耦合等离子体质谱法同时测定土壤中4种重金属元素

采用硝酸-盐酸-氢氟酸作消解体系,以微波消解的方法处理土壤样品,利用ICP-MS同时测定土壤样品中的4种重金属元素(铅、铜、铬、镉)。设定了最佳的样品前处理条件和仪器测定条件,在进行质谱测定时,采用In、Bi、Ge元素作为校正基体效应与信号漂移的内标元素。依据国家标准参考物质并通过加标回收试验,对方法进行了验证。结果表明:该方法所得重金属元素铅、铜、铬、镉的检出限分别为0.010、0.020、0.050、0.005μg/L,加标回收率分别为98%~106%、97%~112%、94%~118%和98%~104%;测定不同土壤标准物质,铅、铜、铬、镉测定结果均在标准值允差范围内,相对标准偏差(RSD)介于0.5%~2.5%。说明该方法稳定性好、精密度高、操作简便、成本低,适用于大量土壤样品4种重金属元素(铅、铜、铬、镉)的同时测定。     

微波消解-石墨炉原子吸收光谱法测定人参中铅和镉

目的建立一种快速准确的微波消解-石墨炉原子吸收光谱法测定人参中铅和镉的含量。方法采用微波消解对样品进行前处理,应用石墨炉原子吸收光谱法测定人参中铅和镉的含量。结果铅在0μg/L~40μg/L范围,镉在0μg/L~3μg/L范围具有良好的线性,相关系数均大于0.999,检出限分别为3.6μg/kg和0.42μg/kg,相对标准偏差(RSD)为9.11%和4.70%,加标回收率在93.3%~106.7%之间。结论该方法简便快速、准确灵敏,适用于测定人参中铅和镉的含量。     

石墨消解-等离子体质谱法测定天然橡胶中14种元素的含量

建立了石墨消解-等离子体质谱（ICP-MS）法快速测定天然橡胶中铅、镉、铜、铬等14种无机元素的方法,旨在为天然橡胶中多元素检测标准的制定提供研究基础。通过优化石墨消解法的前处理条件,再应用ICP-MS测定天然橡胶样品中14种元素（Ba、Na、Mg、K、Ca、Cr、Mn、Fe、Ni、Cu、Zn、Cd、Pb、Co ）的含量,采用在线内标校正基体效应和信号漂移,以确保数据准确性。结果表明,该方法具有较低的检出限,检出限范围为0.0014~0.020 mg/kg,方法回收率86%~96%,RSD在0.53%~6.13%,得到的线性关系良好,充分满足实验要求。石墨消解法操作简便,可按照设定程序自动完成消解全过程,消解时间固定,适用于大批量样品的检测分析,同时,设备以及耗材成本较低。与传统干灰化-原子吸收光谱法相比,本检测方法更适用于天然橡胶中14种无机元素含量的测定,具有耗时短、干扰小、检测范围宽、处理效率高等优点,适用于大批量橡胶样品的多元素检测分析。已应用本实验方法,快速测定了我国6个橡胶主产区中的天然橡胶样品。     

喹硫磷在水稻植株、田水及土壤中的残留消解动态研究

通过湖南、海南和山东2 a 3地田间试验,采用气相色谱分析法研究了喹硫磷在水稻植株、田水和土壤中的残留消解动态。结果表明,在0.02~5.00 mg/kg添加水平下,水稻植株、田水和土壤中喹硫磷的添加回收率为84.8%~104.9%,相对标准偏差为2.1%~5.0%;喹硫磷在水稻植株、田水和土壤中的消解半衰期分别为0.4~4.2,0.7~1.0和4.0~16.9 d,属易降解农药。     

Comparative Assessment of the Efficacy of Various Nitrogen Fertilizers

Summary

The efficiency of N fertilizers is usually poor; often less than 50% of the applied N is taken up by the crop. This review focuses on various N fertilizers with respect to the significance of different N loss pathways, namely (i) ammonia volatilization, (ii) dinitrogen and nitrogen oxide emissions, and (iii) nitrate leaching. Further, the significance of biological N immobilization, ammonium fixation and, finally, the impact of nitrate vs. ammonium uptake on crop yield are also discussed. The reviewed literature shows that N fertilizers may differ markedly in their susceptibility to losses. There is, however, considerable scope to improve N efficiency of each N source by proper N management practices.     

Studies on natural repellents against potato tuber moth (Phthorimaea operculella Zeller) in country stores

Summary The effects of the leaves of five plant species, one from each of the generaAmbrosia, Anemone, Eupatorium, Eucalyptus andLantana, on potato tuber moth were investigated under indigenous storage conditions at the Central Potato Research Station, Shillong (1800 m above sea level). Their action was compared with that of a biological insecticide (spores ofBacillus thuringiensis), a chemical insecticide (carbaryl), and an untreated control. The data collected after six months storage on tuber damage, sprout damage and the rotting indicated that the leaves ofLantana aculeata provided most protection to the tubers, reducing damage from over 70% in the check to below 5%, and sprout damage from over 45% to below 3%. Next best wasEucalyptus globulus followed byB. thuringiensis. They may be used on tubers stored for table use or for seed as they had no adverse effect on germination or on the yield of a subsequent crop.     

Mineral composition of some traditional Mexican teas

Teas of plant origin traditionally consumed by the Mountain Pima of Chihuahua, Mexico, were analyzed for mineral nutritional content. Fe, Cu, Zn, Ca, and Mg composition was determined for native teas made from shoots ofTagetes lucida, T. filifolia, Elytraria imbricata, andHolodiscus dumosus, and from root xylem ofCeanothus depressus andPhaseolus ritensis. Native uses of these teas are also described.     

Novel food and non-food uses for sorghum and millets

Sorghum and millets have considerable potential in foods and beverages. As they are gluten-free they are suitable for coeliacs. Sorghum is also a potentially important source of nutraceuticals such antioxidant phenolics and cholesterol-lowering waxes. Cakes, cookies, pasta, a parboiled rice-like product and snack foods have been successfully produced from sorghum and, in some cases, millets. Wheat-free sorghum or millet bread remains the main challenge. Additives such as native and pre-gelatinised starches, hydrocolloids, fat, egg and rye pentosans improve bread quality. However, specific volumes are lower than those for wheat bread or gluten-free breads based on pure starches, and in many cases, breads tend to stale faster. Lager and stout beers with sorghum are brewed commercially. Sorghum's high-starch gelatinisation temperature and low beta-amylase activity remain problems with regard to complete substitution of barley malt with sorghum malt . The role of the sorghum endosperm matrix protein and cell wall components in limiting extract is a research focus. Brewing with millets is still at an experimental stage. Sorghum could be important for bioethanol and other bio-industrial products. Bioethanol research has focused on improving the economics of the process through cultivar selection, method development for low-quality grain and pre-processing to recover valuable by-products. Potential by-products such as the kafirin prolamin proteins and the pericarp wax have potential as bioplastic films and coatings for foods, primarily due to their hydrophobicity.     

In vitro antimicrobial activity of different accessions ofSolanum commersonii Dun. from Uruguay

Summary The in vitro antimicrobial activity of extracts from accessions ofSolanum commersonii Dun. collected in the south of Uruguay was investigated against five microorganisms including the pathogenRalstonia solanacearum. A total of 30 extracts corresponding to organic and aqueous extracts were studied. Interestingly, most of the positive results for growth inhibition were againstR. solanacearum. The extracts were also analyzed for the presence of glycoalkaloids and lectins. Six of the ten aqueous extracts showed lectin presence and a wide variation in the type and amounts of glycoalkaloids, was found. Results indicate that there is no clear relationship between the antimicrobial activity against the five microorganisms screened and the presence or amounts of lectins and glycoalkaloids, traditionally regarded as possible antimicrobial metabolites in theSolanum genus, which indicates the presence of as yet unidentified antimicrobial compounds.     

Extreme resistance to infection by potato virus X in genotypes of wild tuber-bearingSolanum species

Summary Clones derived from thirty-one different accessions (nineteen of Argentine origin) belonging to eightSolanum species were screened for resistance to infection by potato virus X strain cp (PVX cp) by mechanical inoculation of plantlets that had been micropropagated in vitro. Estimates of PVX multiplication obtained by enzyme linked immunosorbent assay and slot blot nucleic acid hybridization allowed the identification of resistant clones derived from five accessions belonging toS. commersonii S. oplocense, S. sparsipilum andS. tuberosum andigena. Resistant genotypes supported PVX concentrations 5 to 15 times smaller than did the susceptible control cultivar Spunta. Graft inoculation test confirmed the presence of extreme resistance similar to that conferred by the ‘immunity’ gene X¹ (also called RX_act).     

Cyanobacteria Secondary Metabolites as Biotechnological Ingredients in Natural Anti-Aging Cosmetics: Potential to Overcome Hyperpigmentation,Loss of Skin Density and UV Radiation-Deleterious Effects

The loss of density and elasticity, the appearance of wrinkles and hyperpigmentation are among the first noticeable signs of skin aging. Beyond UV radiation and oxidative stress, matrix metalloproteinases (MMPs) assume a preponderant role in the process, since their deregulation results in the degradation of most extracellular matrix components. In this survey, four cyanobacteria strains were explored for their capacity to produce secondary metabolites with biotechnological potential for use in anti-aging formulations. Leptolyngbya boryana LEGE 15486 and Cephalothrix lacustris LEGE 15493 from freshwater ecosystems, and Leptolyngbya cf. ectocarpi LEGE 11479 and Nodosilinea nodulosa LEGE 06104 from marine habitats were sequentially extracted with acetone and water, and extracts were analyzed for their toxicity in cell lines with key roles in the skin context (HaCAT, 3T3L1, and hCMEC). The non-toxic extracts were chemically characterized in terms of proteins, carotenoids, phenols, and chlorophyll a, and their anti-aging potential was explored through their ability to scavenge the physiological free radical superoxide anion radical (O₂^•−), to reduce the activity of the MMPs elastase and hyaluronidase, to inhibit tyrosinase and thus avoid melanin production, and to block UV-B radiation (sun protection factor, SPF). Leptolyngbya species stood out for anti-aging purposes: L. boryana LEGE 15486 presented a remarkable SPF of 19 (at 200 µg/mL), being among the best species regarding O₂^•− scavenging, (IC₅₀ = 99.50 µg/mL) and also being able to inhibit tyrosinase (IC₂₅ = 784 µg/mL), proving to be promising against UV-induced skin-aging; L. ectocarpi LEGE 11479 was more efficient in inhibiting MMPs (hyaluronidase, IC₅₀ = 863 µg/mL; elastase, IC₅₀ = 391 µg/mL), thus being the choice to retard dermal density loss. Principal component analysis (PCA) of the data allowed the grouping of extracts into three groups, according to their chemical composition; the correlation of carotenoids and chlorophyll a with MMPs activity (p < 0.01), O₂^•− scavenging with phenolic compounds (p < 0.01), and phycocyanin and allophycocyanin with SPF, pointing to these compounds in particular as responsible for UV-B blockage. This original survey explores, for the first time, the biotechnological potential of these cyanobacteria strains in the field of skin aging, demonstrating the promising, innovative, and multifactorial nature of these microorganisms.     

Marine Pharmacology in 2009–2011: Marine Compounds with Antibacterial,Antidiabetic, Antifungal,Anti-Inflammatory,Antiprotozoal, Antituberculosis,and Antiviral Activities; Affecting the Immune and Nervous Systems,and other Miscellaneous Mechanisms of Action ?

The peer-reviewed marine pharmacology literature from 2009 to 2011 is presented in this review, following the format used in the 1998–2008 reviews of this series. The pharmacology of structurally-characterized compounds isolated from marine animals, algae, fungi and bacteria is discussed in a comprehensive manner. Antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral pharmacological activities were reported for 102 marine natural products. Additionally, 60 marine compounds were observed to affect the immune and nervous system as well as possess antidiabetic and anti-inflammatory effects. Finally, 68 marine metabolites were shown to interact with a variety of receptors and molecular targets, and thus will probably contribute to multiple pharmacological classes upon further mechanism of action studies. Marine pharmacology during 2009–2011 remained a global enterprise, with researchers from 35 countries, and the United States, contributing to the preclinical pharmacology of 262 marine compounds which are part of the preclinical pharmaceutical pipeline. Continued pharmacological research with marine natural products will contribute to enhance the marine pharmaceutical clinical pipeline, which in 2013 consisted of 17 marine natural products, analogs or derivatives targeting a limited number of disease categories.