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排序方式： 共有178条查询结果，搜索用时 0 毫秒
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Fabian Sandgruber Annekathrin Gielsdorf Anja C. Baur Benjamin Schenz Sandra Marie Müller Tanja Schwerdtle Gabriele I. Stangl Carola Griehl Stefan Lorkowski Christine Dawczynski 《Marine drugs》2021,19(6)
The nutrient composition of 15 commercially available microalgae powders of Arthrospira platensis, Chlorella pyrenoidosa and vulgaris, Dunaliella salina, Haematococcus pluvialis, Tetraselmis chuii, and Aphanizomenon flos-aquae was analyzed. The Dunaliella salina powders were characterized by a high content of carbohydrates, saturated fatty acids (SFAs), omega-6-polyunsaturated fatty acids (n6-PUFAs), heavy metals, and α-tocopherol, whereas the protein amounts, essential amino acids (EAAs), omega-3-PUFAs (n3-PUFAs), vitamins, and minerals were low. In the powder of Haematococcus pluvialis, ten times higher amounts of carotenoids compared to all other analyzed powders were determined, yet it was low in vitamins D and E, protein, and EAAs, and the n6/n3-PUFAs ratio was comparably high. Vitamin B12, quantified as cobalamin, was below 0.02 mg/100 g dry weight (d.w.) in all studied powders. Based on our analysis, microalgae such as Aphanizomenon and Chlorella may contribute to an adequate intake of critical nutrients such as protein with a high content of EAAs, dietary fibers, n3-PUFAs, Ca, Fe, Mg, and Zn, as well as vitamin D and E. Yet, the nutritional value of Aphanizomenon flos-aquae was slightly decreased by high contents of SFAs. The present data show that microalgae are rich in valuable nutrients, but the macro- and micronutrient profiles differ strongly between and within species. 相似文献
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Tanja Bohinc Damir Markovič Stanislav Trdan 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(6):493-500
The aim of present research was to establish the role of epicuticular wax content in eight cabbage genotypes (four white hybrids and one red hybrid, two red varieties and one white variety) in the context of its natural resistance to attack cabbage flea beetles (Phyllotreta spp.) and cabbage stink bugs (Eurydema spp.), which are among the most important cabbage pests in southern Europe. For this reason and for the purpose of diminishing the use of synthetic insecticides against the cabbage pests the field experiments in 2006 and 2008 were conducted. We found out that individual cabbage genotypes – they had different epicuticular wax content – differ in regard to their susceptibility to attacks by the studied groups of harmful insect pests. The highest susceptibility to attacks by Phyllotreta spp. was confirmed for the hybrid ‘Cheers F1’, in the first year (1.68 ± 0.05), as well as in the second year of the experiment (2.87 ± 0.13). Cabbage stink bugs in both years of the experiment caused the highest extent of injuries on the hybrids ‘Destiny F1’, ‘Cheers F1’, and ‘Vestri F1’. In both years we found higher epicuticular wax content in red cabbage genotypes. In almost all studied genotypes we found a pronounced negative correlation between the content of epicuticular wax and the extent of injuries done by both groups of harmful pests. We have established that epicuticular wax is an important factor of cabbage's antixenotic resistance to attacks by cabbage flea beetles and cabbage stink bugs, and that the cabbage genotypes with higher content of this substance are consequently more suitable for environmentally acceptable manners of cabbage production. 相似文献
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The beginnings of food production—animal husbandry and crop cultivation—and of a sedentary way of life represent one of the most drastic changes in human history. Likewise, this is accompanied by an increasing human impact on nature, which is mainly caused by agricultural practices. Agriculture is related to the clearing of forests, tillage, maintenance of the cultivated land, and finally harvesting, which alters not only the vegetation cover but also soil fertility as there is a potential risk for a loss of nutrients. People already countered this loss of nutrients in the times of early agriculture through different techniques and practices. The article summarizes the earliest evidence of fertilization in the prehistory of Central Europe and presents the most important methods for their investigation. What significance fertilization had for early farming societies can presently not be estimated due to the small amount of data. We therefore advocate the development of a routine for sampling during archaeological excavations and for the analysis of various materials (sediment and plant remains) using various methods. For this, the awareness must be raised that anthropogenic sediments, such as pit fills, are important archives for research into the history of humankind. 相似文献
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Pimentel-Elardo SM Buback V Gulder TA Bugni TS Reppart J Bringmann G Ireland CM Schirmeister T Hentschel U 《Marine drugs》2011,9(10):1682-1697
Four new tetromycin derivatives, tetromycins 1-4 and a previously known one, tetromycin B (5) were isolated from Streptomyces axinellae Pol001(T) cultivated from the Mediterranean sponge Axinella polypoides. Structures were assigned using extensive 1D and 2D NMR spectroscopy as well as HRESIMS analysis. The compounds were tested for antiparasitic activities against Leishmania major and Trypanosoma brucei, and for protease inhibition against several cysteine proteases such as falcipain, rhodesain, cathepsin L, cathepsin B, and viral proteases SARS-CoV M(pro), and PL(pro). The compounds showed antiparasitic activities against T. brucei and time-dependent inhibition of cathepsin L-like proteases with K(i) values in the low micromolar range. 相似文献
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Whole cells are attractive biocatalysts, particularly if the reaction requires cofactors or involves multiple transformations. Immobilization of the catalyst is often a prerequisite for continuous processes. The highly cationic chemically modified plasma protein bovine serum albumin (cBSA-147) has been applied for the electrostatically mediated immobilization of the planktonic bacterium E. coli BL21 star (DE3), and the resulting biofilms were superior to those formed on poly-L-lysine coated surfaces. The biocatalyst was immobilized in a capillary column (inside diameter of 530?μm and L=30?m) and evaluated in the enantioselective reduction of ethyl acetoacetate to R-(-)ethyl hydroxybutyrate. In continuous operation in the microreactor format, the productivity of the cells was about 30% higher than that determined in a bench-scale fermentation system. This increase is attributed to the improved mass transfer over short geometrical dimensions. The similarity in the results indicates that studies on a biofilm-coated microreactor can be used for the accelerated collection of data for process optimization. 相似文献