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1.
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Pseudoexfoliation syndrome (PEX), an age-related disorder of the eye, is associated with significant ophthalmic morbidity and can lead to pseudoexfoliation glaucoma (PEG). The etiology of this disorder has not been clearly understood. Trace elements have been suggested to have roles in the pathogenesis of several disorders. This study aimed to determine whether trace element levels have a role in the development of PEX and/or PEG. Levels of zinc (Zn), copper (Cu), selenium (Se), manganese (Mn), chromium (Cr), cobalt (Co), molybdenum (Mo), nickel (Ni), vanadium (V), arsenic (As), aluminum (Al), mercury (Hg), cadmium (Cd), and strontium (Sr) were determined in serum samples of 32 cases of PEX, 30 cases of PEG, and 32 control subjects using inductively coupled plasma–mass spectrometry. Mn, Mo, and Hg concentrations were found to be significantly increased in patients with PEX. Logistic regression revealed Mn and Hg as the strongest determinants of PEX and Mo as the strongest determinant of PEG in the studied Turkish subjects. Levels of Mn, Cr, Co, Mo, Al, Hg, Sr, Ni, V, and As were determined for the first time in these ophthalmological disorders. Increased levels of serum Mn, Mo, and Hg suggest a possible role of these elements in the pathobiology of PEX.  相似文献   

3.
Biological Trace Element Research - The aim of the present study was to investigate hair essential trace elements and mineral levels in 105 pregnant normal-weight (control) and 55 overweight and...  相似文献   

4.
The purpose of this study is to evaluate the cord blood level of toxic and trace elements and to identify their determinants in Terai, Nepal. One hundred pregnant women were recruited from one hospital in Chitwan, Nepal in 2008. The cord blood levels of toxic [lead (Pb), arsenic (As), and cadmium (Cd)], essential trace elements [zinc (Zn), selenium (Se), and copper (Cu)], demographic, socioeconomic, and behavioral variables were measured. The mean values of Pb, As, Cd, Zn, Se, and Cu in cord blood level were found as 31.7, 1.46, 0.39, 2,286, 175, and 667 μg/L, respectively. In the multivariate regression model, cord blood As levels from less educated mothers were higher than those from educated mothers (coefficient = -0.01, 95% confidence interval [CI] = -0.02-0.00). The maternal age was positively associated with the cord blood Cd level (coefficient = 0.02, 95% CI = 0.01-0.03), while it was negatively associated with the cord blood As level (coefficient = -0.01, 95% CI = -0.03--0.01). Cord blood levels of Pb, Zn, Se, and Cu were not associated with maternal age, socioeconomic status, living environment, and smoking status. As and Cd levels were relatively lower than those reported in previous studies in Asia, while the levels of Pb and the trace elements were similar. Less educated mothers are more likely to become a higher in utero As source to their fetus, and fetuses of older mothers were more likely to have higher in utero Cd exposure in Terai, Nepal.  相似文献   

5.
The most efficient steaming conditions below 200 °C for extracting antioxidants from used tea leaves and their reaction behavior during the steaming treatment were investigated. The antioxidative activity of the steamed extracts increased with increasing steaming temperature, and the yield of the ethyl acetate extract fraction from each steamed extract showing the greatest antioxidative activity also increased. Caffeine, (?)-catechin, (?)-epicatechin, (?)-gallocatechin, (?)-epigallocatechin, (?)-catechin gallate, (?)-epicatechin gallate, (?)-gallocatechin gallate, (?)-epigallocatechin gallate and gallic acid were identified from the ethyl acetate extract fraction. Quantitative analyses demonstrated that the catechins with a 2,3-cis configuration decreased with increasing steaming temperature, whereas the corresponding epimers at the C-2 position increased. Each pair of epimers showed similar antioxidative activity to each other, indicating that the epimerization reaction did not contribute to the improved antioxidative activity. It is concluded from these results that the improvement in antioxidative activity at higher steaming temperatures was due to the increased yield of catechins and other antioxidants.  相似文献   

6.

Background

Theaflavins including theaflavin (TF), theaflavin-3-gallate (TF3G), theaflavin-3′-gallate (TF3′G), and theaflavin-3,3′-digallate (TFDG), are the most important bioactive polyphenols in black tea. Because of their poor systemic bioavailability, it is still unclear how these compounds can exert their biological functions. The objective of this study is to identify the microbial metabolites of theaflavins in mice and in humans.

Methods and Findings

In the present study, we gavaged specific pathogen free (SPF) mice and germ free (GF) mice with 200 mg/kg TFDG and identified TF, TF3G, TF3′G, and gallic acid as the major fecal metabolites of TFDG in SPF mice. These metabolites were absent in TFDG- gavaged GF mice. The microbial bioconversion of TFDG, TF3G, and TF3′G was also investigated in vitro using fecal slurries collected from three healthy human subjects. Our results indicate that TFDG is metabolized to TF, TF3G, TF3′G, gallic acid, and pyrogallol by human microbiota. Moreover, both TF3G and TF3′G are metabolized to TF, gallic acid, and pyrogallol by human microbiota. Importantly, we observed interindividual differences on the metabolism rate of gallic acid to pyrogallol among the three human subjects. In addition, we demonstrated that Lactobacillus plantarum 299v and Bacillus subtilis have the capacity to metabolize TFDG.

Conclusions

The microbiota is important for the metabolism of theaflavins in both mice and humans. The in vivo functional impact of microbiota-generated theaflavins-derived metabolites is worthwhile of further study.  相似文献   

7.
The present study aimed at analysing the content of fluorine (F), calcium (Ca), magnesium (Mg), iron (Fe) and zinc (Zn) in the drinks for children and infant formulas, a popular supplement or substitute for breast milk produced from cow milk on an industrial scale. Ca, Mg, Zn and Fe concentrations were determined using atomic absorption spectrophotometer, while F levels using a potentiometric method. F levels in the examined formula samples increased with the intended age range, until the intended age of 1 year, and then decreased. A lower content of Ca, Mg and Zn was observed in formulas intended for children <1 year of age and higher for older children. Fe content increased with the age range. A statistically significant higher content of Ca, Mg, Zn and Fe in samples intended for children with phenylketonuria in comparison to those intended for healthy children or children with food allergies was noted. The content of the analysed elements in juices and nectars showed the highest contents in products intended for infants (under 6 months of age). The lowest levels of elements tested were found in drinks for children over 6 months of age. In conclusion, the concentrations of the examined elements in infant formulas and juices for children were decidedly greater than the standards for the individual age groups. Although the absorption of these elements from artificial products is far lower than from breast milk, there is still the fear of consequences of excessive concentrations of these minerals.  相似文献   

8.
Leaf carbon isotope ratios and 13 kinds of mineral elements were measured on 36 species of common Chinese medicinal plants in a subtropical monsoon forest of Ding Hu Shan in Guangdong Province. The δ13C value were from –26.4 to –32.6%, indicating that all of the species belonged the photosynthetic C3 types. The relative lower value of δ13C was observed in the life form of shrubs. The contents of 7 elements (N, P, K, Ca, Na Mg, Si) were dependent upon the species, life form, medicinal function and medicinal part. Herb type medicine and the used medicinal part of leaves or whole plant showed higher levels of above elements than the others. Among the nine groups with different medicinal functions, it was found that more nitrogen was in the leaves of medicinal plants for hemophthisis, hypertension and stomachic troubles, more phosphorus and potassium were in the leaves for cancer and snake bite medicines, but more calcium and magnesium were in the leaves for curing rheumatics. Ferric, aluminium and manganese were the main composition of microelements in leaves. There were higher content of ferric in leaves for hemophthisis medicine, higher zinc in leaves for cold and hypertension medicine, and higer cuprum in leaves of stomachic medicine. It was suggested that the pattern of mineral elements in leaves of Chinese medicinal plants reflected the different properties of absorption and accumulation. Some additional effect due to the high content of certain element might be associated with the main function of that medicine.  相似文献   

9.
Black currant cuttings were grown with six levels of potassiumand two levels of phosphorus. Shoot length, leaf number, leafweight, and deficiency symptoms were recorded 11 and 16 weeksafter commencement of the treatments, and leaf samples wereanalysed for putrescine, potassium, and nitrogen. Shoot length,leaf number and leaf weight were reduced by potassium deficiency,the greatest effect being observed in leaf weight Potassium-deficiencysymptoms appeared first on the lower branches, the most severedeficiency symptoms being found on the plants grown with highphosphate. In terms of the fresh weights, the highest concentrationof both putrescine and potassium were found in the leaves ofthe upper shoots. Lower putrescine and higher potassium levelsin the leaves were found in the low-phosphate nutrient series.In terms of cation equivalents the deficit of potassium wascompensated to the extent of 30 per cent by the formation ofputrescine.  相似文献   

10.
The incidence of hypertension has been associated to cigarette smoking and consumption of alcohol. In the present study, trace and toxic elements were determined in scalp hair of patients diagnosed with hypertension who are smokers and habitual alcohol drinkers living in Dublin, Ireland. These results were compared with age- and sex-matched healthy, nonsmokers, nondrinking controls. The concentrations of trace and toxic elements were measured by inductively coupled plasma atomic emission spectrophotometer after microwave-assisted acid digestion. The validity and accuracy of the methodology were checked using certified reference material (NCS ZC 81002b) and by the conventional wet acid digestion method on the same certified reference material and on real samples. The recovery of all the studied elements was found to be in the range of 97.5%–99.7% in certified reference material. The results of this study showed that the mean values of cadmium, copper, iron, nickel and lead were significantly higher in scalp hair samples of both smoker and nonsmoker hypertensive patients than referents (P < 0.001); whereas, the concentration of zinc was lower in the scalp hair samples of hypertensive patients of both genders. The deficiency of zinc and the high exposure of trace and toxic metals as a result of cigarette smoking and alcohol consumption may be synergistic with risk factors associated with hypertension.  相似文献   

11.
12.
This study analyzed boron content in commonly consumed foods by Koreans. Boron content was analyzed on 299 different foods using inductively coupled plasma atomic emission spectroscopy. The content of boron in cereals, potatoes, starches, sugars, and confectionaries was 1.11 to 828.56 microg per 100 g. As for beans, nuts, and seeds, the content of boron in acorn starch jelly was 66.15 microg per 100 g and in soybeans 1,642.50 microg per 100 g. In fruits, records show 5.29 to 390.13 microg per 100 g. The content of boron in vegetables was 17.45 to 420.55 microg per 100 g and in mushrooms 2.97 to 526.38 microg per 100 g. As for meats, eggs, milks, and oils, it posted 1.48 to 110.01 microg per 100 g. Fishes, shellfishes, and seaweeds contained 1.20 to 6,300.83 microg per 100 g of boron. Beverages, liquors, seasonings, and processed foods posted 1.06 microg per 100 g in corn cream soup and 2,026.49 microg per 100 g in cocoa. It is suggested that the data for the analysis of boron content in foods need to be more diversified and a reliable food database needs to be compiled based on the findings of the study to accurately determine boron consumption.  相似文献   

13.
Fresh tea leaves were homogenized in a chloroform-methanol mixture (1:1, v/v), and separated into chloroform-soluble and methanol-water-soluble fractions after addition of water. From the chloroform-soluble fraction, the volatile forms of the aroma compounds were obtained. The non-volatile forms of the aroma compounds were associated with the methanol-water-soluble fraction, and were converted to volatile forms by hydrolysis with dilute acid.

The amount of the aroma compounds in the free form, such as cis-3-pentenol, hexanol, cis-3-hexenol, trans-2-hexenol, linalool, linalool oxide (cis, 5-membered), linalool oxide (trans, 5-membered), linalool oxide (trans, 6-rnembered), linalool oxide (cis, 6-membered), nerol, geraniol, phenylmethanol, and 2-phenylethanol, markedly increased during black tea manufacture. However, those in the bound form, showed a slight decrease during the manufacture. The increases in the former were also brought about by maceration, or treatment of the tea leaves with monoiodoacetate or malonate.  相似文献   

14.
Iron (Fe) and zinc’s (Zn) interaction at the absorptive level can have an effect on the success of co-fortification of wheat flour with both minerals on iron deficiency prevention. The aim of the study was to determine the effect of increasing levels of zinc fortificant on the iron absorption of bread co-fortified with iron and zinc consumed with a black tea. Twelve women aged 33–42 years participated in the study. They received on four different days 200 mL of black tea and 100 g of bread made with wheat flour (70 % extraction) fortified with either 30 mg Fe/kg alone, as ferrous sulfate (A), or with the same Fe-fortified flour, but with graded levels of Zn, as zinc sulfate: 30 mg/kg (B), 60 mg/kg (C), or 90 mg/kg (D). Fe radioisotopes (59Fe and 55Fe) of high specific activity were used as tracers, and Fe absorption iron was measured by the incorporation of radioactive Fe into erythrocytes. The geometric mean and range of ±1 SD of Fe absorption were as follows: A?=?6.5 % (2.2–19.3 %), B?=?4.6 % (1.0–21.0 %), C?=?2.1 % (0.9–4.9 %), and D?=?2.2 % (0.7–6.6 %), respectively; ANOVA for repeated measures F?=?10.9, p?<?0.001 (Scheffè’s post hoc test: A vs. C, A vs. D, B vs. C, and B vs. D; p?<?0.05). We can conclude that Fe absorption of bread made from low-extraction flour fortified with 30 mg/kg of Fe, as ferrous sulfate, and co-fortified with zinc, as zinc sulfate consumed with black tea is significantly decreased at a zinc fortification level of ≥60 mg/kg flour.  相似文献   

15.
黑米中矿质元素铁、锌、锰、磷含量的遗传效应研究   总被引:23,自引:2,他引:23  
采用禾谷类作物种子胚乳数量性状模型,分析黑米稻品种双列杂交F1和F2种子的Fe、Zn、Mn、P含量的遗传效应。结果表明,4种矿质元素含量同时受制于种子直接遗传效应、母体效应和细胞质作用影响。其中,Fe、Zn、Mn含量的种子直接效应比母体效应和细胞质效应的作用更大;P含量则主要受种子直接加性、母体加性和显性效应共同作用。Fe、Zn、Mn含量的种子直接遗传率较高,在杂种早代分别结合农艺性状选择单株上各  相似文献   

16.
γ-l-Glutamyl-l-methioninesulfoxide was isolated from green gram seed. The peptide, isolated from plant material for the first time, was present in large amounts in seeds, but was not detected in commercially obtained etiolated seedlings as was the case with other γ-glutamyl peptides.  相似文献   

17.
水稻籽粒矿质元素含量遗传及主要农艺性状相关性分析   总被引:2,自引:0,他引:2  
通过了解水稻子粒钙、镁、铜、铁、锌和硒等矿质元素含量,以绿旱1号作为父本与102S、KD36S、7HS012及7HS013不育系为母本进行配组,对父本与杂交后代主要农艺及经济性状、水稻子粒中的矿质元素含量进行了遗传分析,并对各杂交后代的主要农艺性状和子粒中矿质元素含量以及各矿质元素含量间进行了相关性分析.结果表明,杂交后代农艺及经济性状多数表现出超高亲分离现象,且LK3的农艺及经济性状均表现为最好.水稻子粒矿质元素含量与部分农艺和经济性状存在明显的正相关或负相关关系,且K、Mg、Zn、Se等元素含量与水稻产量密切相关.水稻子粒中矿质元素含量大小依次为P>K >Mg >S> Ca> Mn >Fe >Zn >Cu >Se,4个杂交后代的K元素含量表现出超高亲分离现象,LK2、LK3和LK4的Fe元素含量也表现出超高亲分离现象.水稻子粒大量与微量元素之间相关性最高,微量元素之间相关性次之,大量元素之间相关性最小,以7HS012不育系为母本得到的杂交后代农艺性状表现较好,矿质元素含量最高,7HS013次之,其他不育系表现一般.本研究为选育出耐旱及营养价值高的水稻新品种母本的选择提供了理论依据.  相似文献   

18.
Trace elemental content was analysed in edible tissues of Mytilus galloprovincialis collected in five different sampling areas near the mouth of river Tagus estuary in Lisbon. The concentrations of essential elements (S, K, Ca, Fe, Cu, Zn, As, Br and Sr) were determined by energy-dispersive X-ray fluorescence (EDXRF) spectrometry, while toxic elements (Cr, Cd, Hg, Se and Pb) were measured by inductively coupled plasma-atomic emission spectrometry (ICP-AES). The results show that the essential elements K and S are present at the highest concentrations in all the studied samples reaching 2,920 and 4,520 μg g?1 (fresh weight), respectively. The highest levels of heavy metals found were in two areas close to the city for Pb and Cd, but below the maximum allowed values.  相似文献   

19.
A novel marine ice-nucleating bacterium, KUIN-5, was isolated from a marine algae, Monostroma latissum. Strain KUIN-5 was identified as a Pseudomonas sp. from its characteristics and taxonomies; the optimum temperature and pH for its growth were 25°C and 6.0, respectively. When strain KUIN-5 was aerobically cultured in Carlucci-Pramer medium (pH 6.0) for 50 h at 25°C, the highest ice-nucleating activity of the cells among the media for marine bacteria was obtained, and the ice-nucleating temperature, T50, was indicated to be ? 3.2°C. Also, the optimum concentration of NaCl for the growth in this medium, which was prepared with distilled water instead of seawater, was 2.0% (w/v) and then the ice-nucleating activity was inversely proportional to the NaCl concentration. Moreover, when strain KUIN-5 was cultured in Davis medium under optimum conditions, it produced insoluble polysaccharide (IPS) in the culture. The maximum amount of IPS production by strain KUIN-5 was 84.5 mg/ml of medium under optimum conditions. Therefore, this IPS was isolated and could be identified as cellulose, based on TLC or HPLC of the acid hydrolysate, and GC-MS of the acetylated polyalcohol prepared by periodate oxidation and Smith degradation of this polysaccharide. This is the first report of cellulose production by a marine ice-nucleating bacterium.  相似文献   

20.
Two isozymes of ascorbate (AsA) peroxidase were found in tealeaves, and one of them (AsA peroxidase II) was purified tohomogeneity, as judged by polyacrylamide gel electrophoresis.AsA peroxidase II is a monomer with a molecular weight of 34,000and contains protoheme, but it is not a glycoprotein. The enzymeshowed a Soret peak at 409 run and at 420 nm when oxidized andreduced, respectively, with an a-band at 556 nm. The oxidizedenzyme showed two small peaks at 478 nm and 530 nm. The peakat 478 nm disappeared when the enzyme was inactivated by depletionof AsA or by the addition of cyanide. Antibody raised againstAsA peroxidase II from tea did not cross-react with guaiacolperoxidase from spinach, and antibody against the guaiacol peroxidasedid not with AsA peroxidases from tea leaf. The amino acid compositionand amino acid sequence of the amino-terminal region of AsAperoxidase II were determined. Little homology in terms of aminoacid sequence was found between AsA peroxidase II and variousguaiacol peroxidases. The enzymatic and molecular propertiesof the two isozymes showed distinct differences with respectto molecular weight, sensitivity to AsA-depletion, specificityfor the electron donor, and other enzymatic properties. (Received April 13, 1989; Accepted July 25, 1989)  相似文献   

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