松口蘑中微量元素的测定

采用火焰原子吸收法同时测定了松口蘑中K、Ca、Na、Mg、Fe、Pb、Cd、Co、Cr、Zn、Mn、Cu等12种元素的含量。方法的相对标准偏差在0.08％－2.32％范围,回收率在97.1%－108.3%范围。结果表明,在三种松口蘑样品中,除含有较高的K、Na、Ca、Mg和一定量的有害元素Cd、Pb外,其余6种对人体有益的微量元素较为丰富。     

Trace element profile of a wild edible mushroom (Suillus granulatus)

Seventeen elements, Al, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Ni, P, Pb, V, and Zn (macroelements and trace elements) were investigated by Atomic Spectrometries on a particular wild edible mushroom collected in the central region of Argentina during 2 different years in the same season. The metal content profile in Suillus granulatus samples is given. The found quantities of Na, K, Ca, Mg, Fe, P, V, and Al were 0.40, 10.84, 0.48, 0.30, 0.57, 4.24, 0.18, and 1.23 g/kg dry weight, respectively. The levels of Li, Cu, Zn, Cd, Co, Ni, Cr, and Mn were 0.98, 23.02, 22.30, 0.26, 0.16, 1.17, 0.90, and 28.75 mg/kg dry weight, respectively. Pb was not detected at the investigated levels. The results indicate that the levels of metals in the analyzed samples are not considered to be a health risk. In order to demonstrate the validity of our method, a recovery study was performed with acceptable results.     

Mineral constituents of edible parasol mushroom Macrolepiota procera (Scop. ex Fr.) Sing and soils beneath its fruiting bodies collected from a rural forest area

Concentrations and interrelationships of twenty elements were studied in parasol mushroom and in the top layer of soil (0–10 cm) from the area of Kiwity (Poland). K, P, Mg, Ca, and Zn were found to be the most abundant elements in the mushroom. Higher concentrations of Fe, Mn, Na, Ni occurred in stipes then in caps, while Cd, Cr, Cu, Hg, Rb dominated in caps. Ag, Al, and Ba concentrations in caps and stipes were similar. Parasol mushroom is efficient in up-take and separation of Ag, Cd, Cu, Hg, K (in caps, the bioconcentration factor is BCF ≥ 100), Na, P, Rb (50 < BCF < 100), and Mg, Zn (BCF > 10) in its fruiting bodies, while Al, Ba, Ca, Co, Cr, Fe, Mn, Sr, and Pb are eliminated (BCF < 1). Parasol mushroom from rural forest area in the north-eastern region of Poland is of hygienic concern for human health because of toxic mercury and cadmium content in the edible caps, which are also rich in essential Cu, Fe, and their K, Mn, and Zn content is also high.     

Trace element content of phosphorite reference materials (BCR-RM-032, PRH and IAEA-434)

Analysis of geological materials requires the use of matrix specific reference materials (RMs). Phosphate rocks (PR), the basic ingredient of phosphate fertilizers, are very important in agriculture. A project was undertaken to study the PRs of the Hazara Deposits of Pakistan. Due to the unavailability of phosphate rock reference materials (PR-RMs) with a large number of certified elements, validation of the results was problematic when carrying out elemental analysis of PR samples and their derived products. Therefore a parallel study was performed to determine the composition of three phosphate based RMs; BCR-RM-032 (Natural Moroccan Phosphorite), IAEA-434 (Phosphogypsum) and PRH (a local PR-RM from the Hazara Deposits of Pakistan). Instrumental Neutron Activation Analysis was used for this purpose and more than 30 elements including rare earth elements were determined in the three PR samples.     

Silver-protein (core-shell) nanoparticle production using spent mushroom substrate

A simple route for the synthesis of silver-protein (core-shell) nanoparticles using spent mushroom substrate (SMS) has been demonstrated in this work. SMS exhibits an organic surface that reduces silver ions and stabilizes the silver nanoparticles by a secreted protein. The silver nitrate solution incubated with SMS changed to a yellow color from 24 h onward, indicating the formation of silver nanoparticles. The purified solution yielded the maximum absorbance at 436 nm due to surface plasmon resonance of the silver nanoparticles. X-ray analysis of the freeze-dried powder of silver nanoparticles confirmed the formation of metallic silver. Transmission electron microscopic analysis of the samples showed a uniform distribution of nanoparticles, having an average size of 30.5 +/- 4.0 nm, and its corresponding electron diffraction pattern confirmed the face-centered cubic (fcc) crystalline structure of metallic silver. The characteristic fluorescence of the protein shell at 435 nm was observed for the silver nanoparticles in solution, when excited at 280 nm, while Fourier transform infrared (FTIR) spectroscopy confirmed the presence of a protein shell. The silver nanoparticles were found to be stable in solution for more than 6 months. It is observed that the reducing agents from the safflower stalks caused the reduction of silver ions while protein secreted by the fungus stabilized the silver nanoparticles. These silver nanoparticles showed excellent antibacterial activity against two representative bacteria, Staphylococcus aureus (Gram positive) and Klebsiella pneumoniae (Gram negative), in spite of the presence of an organic layer as a shell. Apart from ecofriendliness and easy availability, "SMS" as a biomanufacturing unit will give us an added advantage in ease of handling when compared to other classes of microorganisms.     

Antimony as a traffic-related element in size-fractionated road dust samples collected in Buenos Aires

The growing interest of public opinion in environmental problems conducted us to investigate the levels of a toxic traffic-related element such antimony in 19 size-fractionated street dust samples. Samples were collected in the megacity of Buenos Aires during two months at 19 sites with different urban characteristics and traffic profile. Samples were sieved in four fractions (F1 < 37 µm, F2: 37-55 µm, F3: 55-75 µm and F4: 55-100 µm) before elemental analysis. A mixture of aqua regia and hydrofluoric acid was used to digest all samples. Antimony concentrations were quantified by inductively coupled plasma optical emission spectrometry (ICP OES) or flow injection hydride generation-atomic absorption spectrometry (FI-HG-AAS).Twenty four out of 73 sub-samples analyzed showed Sb levels < 0.05 µg g^− 1; in the rest of the samples mean Sb concentrations varied from 1.4 to 20.4 µg g^− 1. Maximum and minimum concentrations (in µg g^− 1) found in individual samples in the four fractions were: Fraction 1, < 0.05-20.4; Fraction 2, < 0.05-18.4; Fraction 3, < 0.05-6.3; Fraction 4, < 0.05-7.7.Antimony was found to be enriched in the smallest size fraction of road dust, with mean enrichment factors varying between 27 (F3) and 272 (F1). Concentrations of Sb were correlated with those of other traffic-related elements such as Cu and Pb and higher levels were found in areas with medium and high traffic densities.     

Antioxidant compounds from propolis collected in Anhui, China

The antioxidant activities of the chloroform, ethyl acetate and n-butanol extract fractions from propolis collected in Anhui, China were evaluated in this study. The ethyl acetate fraction contained the highest amount of total phenolics and total flavonoids, and showed the greatest 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging capacities and Ferric Reducing/Antioxidant Power (FRAP). The antioxidant activity of twenty-two compounds isolated from the ethyl acetate fraction was also evaluated using the above-mentioned three assays. The results indicated that phenolics contributed to the antioxidant activity of propolis collected in Anhui, China. Therefore, propolis collected in Anhui, China and its phenolics might be used as a natural antioxidant.     

Speciation and health risk considerations of arsenic in the edible mushroom Laccaria amethystina collected from contaminated and uncontaminated locations

Samples of the edible mushroom Laccaria amethystina, which is known to accumulate arsenic, were collected from two uncontaminated beech forests and an arsenic-contaminated one in Denmark. The total arsenic concentration was 23 and 77 μg As g⁻¹ (dry weight) in the two uncontaminated samples and 1420 μg As g⁻¹ in the contaminated sample. The arsenic species were liberated from the samples using focused microwave-assisted extraction, and were separated and detected by anion- and cation-exchange high-performance liquid chromatography with an inductively coupled plasma mass spectrometer as arsenic-selective detector. Dimethylarsinic acid accounted for 68–74%, methylarsonic acid for 0.3–2.9%, trimethylarsine oxide for 0.6–2.0% and arsenic acid for 0.1–6.1% of the total arsenic. The unextractable fraction of arsenic ranged between 15 and 32%. The results also showed that when growing in the highly arsenate-contaminated soil (500–800 μg As g⁻¹) the mushrooms or their associated bacteria were able to biosynthesize dimethylarsinic acid from arsinic acid in the soil. Furthermore, arsenobetaine and trimethylarsine oxide were detected for the first time in Laccaria amethystina. Additionally, unidentified arsenic species were detected in the mushroom. The finding of arsenobetaine and trimethylarsine oxide in low amounts in the mushrooms showed that synthesis of this arsenical in nature is not restricted to marine biota. In order to minimize the toxicological risk of arsenic to humans it is recommended not to consume Laccaria amethystina mushrooms collected from the highly contaminated soil, because of a genotoxic effect of dimethylarsinic acid observed at high doses in animal experiments. © 1998 John Wiley & Sons, Ltd. No Abstract.     

Element content and element correlations in Chinese human liver

The amounts of the 19 elements As, Br, Ca, Cd, Ce, Co, Cr, Cs, Fe, K, La, Mo, Na, Rb, Sb, Sc, Se, Sm, and Zn in 92 lyophilized autopsy human liver samples from normal subjects have been analyzed by instrumental neutron-activation analysis (INAA). For intercomparison and quality control ten samples were independently analyzed in two institutes, the Institute of High Energy Physics in China and the Joef Stefan Institute in Slovenia. Most of the element contents determined by the two institutes were in quite good agreement, even though different experimental conditions were applied, indicating the reliability of the analytical results. Analysis of the chemical species of mercury present in the ten liver samples was also performed in Slovenia. Possible differences between the element content of male and female liver samples were studied by means of Students t-test, but significant differences were found only for Ce, Co, Fe, La, Mo, and Zn. The results obtained were also compared with those reported from other areas of the world; no appreciable differences were observed. Correlation among the various elements in the human liver samples was studied using multivariate statistics. It was found that there was relatively close correlation between some elements, for example As–Fe, Ca–Fe, Cd–Co, Cd–Zn, Mo–Zn, Co–Se, Cs–Rb, Br–Rb, Sc–Sm, La–Sm, La–Ce, etc.; these correlations could be rationally explained by the similarity of the electronic structures of the elements and/or their physiological functions in the human body.     

Four new eremophilane-type alcohols from Cremanthodium helianthus collected in China

Four new eremophilane-type sesquiterpenoid alcohols were isolated from Cremanthodium helianthus collected in China and their structures established on the basis of spectroscopic analyses. All of them had 9-en-8-one partial structures with one more double bond either delta11, delta11(13), or delta7(11). Two of them had a hydroxy group at C-1 position.     

Heavy metals content in rain water collected in three different locations in Italy during 1999

Rain water samples collected at three different locations in Italy during 1999 were analysed for heavy metals determination. Results for V, Cr, Mn, Co, Cu, Cd, Sb, Pb, Al and Ni are reported in this paper. For most of the elements higher concentration values have been measured in the samples from Alpe Gera (rural site): only for Cd and V were the concentrations higher at Pisa. The total annual deposition (microg m(-2) y(-1)) shows a similar behaviour, with Alpe Gera being the location with highest total annual input for Cr, Mn, Co, and in particular for Cu, Sb, Pb and Al. The reason of the higher deposition at a rural site in comparison to a urban one (Milan) is not known: further experimental work and investigations are needed. Generally, no evident seasonal trends have been observed for the measured concentrations, while few correlations have been found among elements within the same station. Crustal contribution to total concentration varies from about 20% for V to less than 1% for Cu, Cd, Sb, Pb and Ni.     

Cytotoxic and antimicrobial aporphine alkaloids from Fissistigma poilanei (Annonaceae) collected in Vietnam

Two new aporphine alkaloids: 8-hydroxy-9-methoxy-1,2-methylenedioxyaporphine (1) and 8-hydroxy-3,9-dimethoxy-1,2-methylenedioxyaporphine (2) were isolated from the ethyl acetate extract of Fissistigma poilanei along with five known compounds: oxocrebanine (3), kuafumine (4), (2R,3R)-3',4',5,7-tetrahydroxydihydroflavonol-3-O-α-L-rhamnopyranoside (5), (+)-catechin 3-O-α-L-rhamnopyranoside (6) and quercetine 3,7-dimethoxy-3'-O-α-L-rhamnopyranosyl-(1?→?2)-β-D-glucopyranoside (7). These two new aporphine alkaloids exhibited a moderate cytotoxic activity against four human cancer cell lines (KB, Hep-G2, MCF-7, LU) as well as antimicrobial activity against Lactobacillus fermentum, Enterococcus faecium, Staphylococcus aureus and Bacillus subtillis.     

Mineral content and physical properties of local and imported honeys in Saudi Arabia

In addition to color, ash and electrical conductivity (EC), the levels of 14 minerals were investigated in 23 varieties of honey from Saudi Arabia and six other countries. The quantities of the macrominerals obtained were as follows (in ppm): K (298.60–491.40), Mg (80.70–199.30), Ca (60.75–99.95), P (21.10–33.29), and Na (15.69–26.93). The quantities of trace minerals were as follows (in ppm): Fe (67.18–98.13), I (12.61–94.68), Mn (4.15–6.04), Zn (3.44–5.72), Li (1.15–4.26), Co (1.00–1.32), and Ni (0.15–0.67). The quantities of the heavy metals Pb and Cd were found to be 0.06–0.23 and 0.00–0.16, respectively. The values of the tested elements—color, ash and EC—varied among the tested honeys according to their botanical origin. Dark honeys, especially acacia honeys, had higher elemental content and EC values than lighter ones. Saudi and Yemeni seder honeys exhibited no distinctive characteristics in their tested parameters. The levels of heavy metals indicated that the tested honeys were safe for human consumption.     

Four new guaianolides and acetylenic alcohol from Saussurea katochaete collected in China

Four new guaianolides and an acetylenic alcohol were isolated from Saussurea katochaete (Asteraceae) collected in China. The structures were determined based on the spectroscopic data including the absolute configuration by application of advanced Mosher's method.     

A sensitive optical element for mercury(II)

A transparent polymethacrylate matrix modified with copper dithizonate was used to determine mercury(II). Optimum conditions for modifying the polymethacrylate matrix with copper dithizonate were found, and its reaction with mercury(II) in model solutions was studied.     

Determination of polycyclic aromatic hydrocarbons (PAHs) in particulate matter collected with low volume samplers

The determination of polycyclic aromatic hydrocarbons (PAHs) contained in samples of particulate matter (PM), collected with low volume pumps, were carried out with an high sensitivity method that comes from several revisions of a previous method. The present work describes how, by using programmable temperature vaporization (PTV) and a mass selective detector with inert ionic source for the GC-MS analysis and the modifications of microwave-assisted extraction (MAE), the sensitivity of the method can be increased.The PAHs chosen for testing the method are: benzo[a]anthracene (BaA), benzo[b]fluoranthene (BbF), benzo[k]fluoranthene (BkF), benzo[a]pyrene (BaP), indeno[1,2,3-cd]pyrene (Ip) and dibenzo[a,h]anthracene (DbA). They, in fact, belong to that group of substances that are the most harmful for human health for their carcinogenicity.PAHs recoveries for spiked standard solutions at different concentrations were between 95 and 100% with relative standard deviation ranging from 1 to 3%. The revised method was validated using a 1649a urban dust standard reference material (SRM). The results obtained were in good agreement with certified values. The high sensitivity of the method allows to carry out analyses using only a half of the sampled filter (usually 47 mm diameter membranes). In this way, the other half can be used for the characterization of the other components of PM (heavy metals, organic carbon, ions, etc). The last step has been constituted by application of the optimized method on real samples collected in two cities located in Southern Italy (Bari and Taranto).