Improved organoleptic and nutritive properties of bakery products supplemented with amino acid overproducing Saccharomyces cerevisiae yeasts

Spontaneous yeast mutants isolated in continuous culture as resistant to toxic amino acid analogues, able to increase up to 40 times their free amino acid pool of Thr, up to 160 times their pool of Met, or up to 20 times their pool of Lys, were characterized with regard to properties of industrial interest. Growth rate, mu (h(-1)), and biomass yield, Y (g/L), of the amino acid overproducing mutants (AA(S)) were in many cases similar to those of the wild type, whereas their free amino acid content was substantially increased in laboratory and industrial media (molasses). Doughs fermented with 3% baker's yeast and 0.5% AA(S) mutants produced bakery products that displayed texture similar to those fermented with 3.5% baker's yeast, but the former had a considerable improvement of their taste and aroma. On the other hand, bread content of the essential amino acids Lys, Met, and Thr provided by yeast was also increased.     

The fluorescent toolbox for assessing protein location and function

Advances in molecular biology, organic chemistry, and materials science have recently created several new classes of fluorescent probes for imaging in cell biology. Here we review the characteristic benefits and limitations of fluorescent probes to study proteins. The focus is on protein detection in live versus fixed cells: determination of protein expression, localization, activity state, and the possibility for combination of fluorescent light microscopy with electron microscopy. Small organic fluorescent dyes, nanocrystals ("quantum dots"), autofluorescent proteins, small genetic encoded tags that can be complexed with fluorochromes, and combinations of these probes are highlighted.     

青海班玛地区藏族药用民族植物学研究

对青海班玛地区藏族药用民族植物学进行了调查。结果表明,班玛地区藏族药用植物有478种,隶属于70科228属,藏族在选择药用植物种类、药用部位、采收季节、加工炮制、饮用方法等方面具有独特性。为该地区的药用植物资源的保护和可持续利用,提出了相应的建议。     

Root-zone temperature affects the phytoextraction of iron in contaminated soil

The effect of root temperatures on the uptake and content of iron (Fe) in different organs of potato plants was studied. Four different plastic covers were used (T1: transparent polyethylene; T2: white polyethylene; T3: white and black coextruded polyethylene), using plants without plastic covers as control (T0). The results of this study indicate that in treatments with the highest root temperature (T2 and T3), chelate-reductase activity significantly increased, that could enhance the uptake and subsequent accumulation of Fe in the different organs analyzed of the potato plant. In addition, the roots and particularly the tubers proved to be the main organs of Fe bioaccumulation in treatments T0, T2, T3, and T4. On the contrary, in the T1 treatment, the bioaccumulation of Fe was detected in the shoot (stems and leaves). Finally, the foliar bioindicators of Fe analyzed, chl a and b, carotenes, peroxidase activity and catalase activity reflected the foliar status of Fe.     

杀线虫剂产品研究进展

植物寄生线虫是植物的一类重要病原物,全世界每年因线虫造成的损失大约1500亿美元.本文就目前全球杀线剂的市场需求、国外杀线剂农药登记情况、我国杀线剂农药登记情况与生产企业分布情况及杀线剂开发过程中存在的主要问题等方面展开分析,能够为杀线剂产品的研究提供理论基础.     

JNK抑制剂对仔猪肝细胞药物性损伤的缓解作用及其机理

【目的】研究c-Jun氨基末端激酶(JNK)抑制剂SP600125对仔猪原代肝细胞药物性损伤的缓解作用及机理。【方法】通过二步灌流法获得仔猪原代肝细胞,将肝细胞分为对照组(C)、JNK抑制剂组(SP)、模型组(M)和治疗组(T),每组6个重复。对照组细胞不添加药物,SP组用2μmol/L SP600125处理细胞,M组用80μg/mL脂多糖(LPS)+20μg/mL恩诺沙星(ENR)处理细胞,T组用80μg/mL LPS+20μg/mL ENR+2μmol/L SP600125处理细胞,处理12 h后,收集上清测定谷丙转氨酶(ALT)和谷草转氨酶(AST)活性,收集细胞测定谷胱甘肽过氧化物酶(glutathione peroxidase, GSH-Px)、超氧化物歧化酶(superoxide dismutase, SOD)活性、丙二醛(malondialdehyde, MDA)含量及肝细胞核因子-1(hepatocyte nuclear factor 1,HNF-1)和谷胱甘肽-S-转移酶A1(glutathione S-transferase alpha 1,GSTA1)mRNA的相...     

Preferred foraging areas of Heard Island albatrosses during chick raising and implications for the management of incidental mortality in fisheries

• 1. Incidental mortality in fisheries is causing declines in many albatross populations around the world. To assess potential interactions with regional fisheries satellite tags were used to track black-browed albatrosses (Thalassarche melanophrys) and light-mantled sooty albatrosses (Phoebetria palpebrata) breeding on Heard Island during the chick-rearing periods of 2003/04. This was the first time individuals from either population had been tracked.
• 2. Black-browed albatrosses foraged largely within the Heard and McDonald Islands Economic Exclusion Zone (EEZ) north-east of the island, although 20% of foraging trips were to areas north of the EEZ into Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) areas 58.5.1 and 58.5.2 and into the Îles Kerguelen EEZ.
• 3. In contrast, the light-mantled sooty albatrosses foraged well south of Heard Island along the southern boundary of the Antarctic Circumpolar Current. Both species appear to face minimal risk of incidental mortality during the chick-rearing period in the regulated, legal fisheries, but are threatened by illegal, unreported and unregulated (IUU) fishing vessels operating in the southern Indian Ocean.

Copyright © 2007 John Wiley & Sons, Ltd.     

Larval fish distribution and retention in the Canary Current system during the weak upwelling season

The spatial distribution of fish larvae was studied in the Canaries‐African Coastal Transition Zone, outside the strong upwelling season. An onshore–offshore transition in the larval fish community structure was observed, from a coastal assemblage dominated by small pelagics (sardine, anchovy, mackerel), bounded by the upwelling front, to an offshore assemblage dominated by mesopelagic species (mainly Myctophidae, Phosichthydae, Gonostomatidae). Distribution of the neritic larvae was deeply influenced by the intense mesoscale activity found in the area, both horizontally (larvae were advected offshore but were always retained within the upwelling area) and vertically (larvae were deepened in the vicinity of two anticyclonic eddies). A combined effect of the upwelling front and a cyclonic–anticyclonic eddy dipole is likely the successful retention mechanism for these larvae. These results support the current belief that retention may be higher than previously thought in upwelling areas. Oceanic larvae were also collected in higher abundances near the front and an anticyclonic eddy. Neritic and oceanic larvae frequently showed a differentiated position in the water column, although they sometimes coexisted. Finally, larval connectivity between Islands within the Canary archipelago is suggested. The present study thus contributes to the understanding of the complex dispersal and retention processes in the Canaries‐African Coastal Transition Zone. However, results also highlight the poor knowledge of this region compared with the other three main Eastern Boundary Upwelling Systems in terms of ichthyoplankton dynamics. The importance of routine monitoring programs of commercial and non‐commercial species in the area is emphasized.     

Importance of the relative levels of dietary arachidonic acid and eicosapentaenoic acid for culture performance of gilthead seabream (Sparus aurata) larvae

The effect of different arachidonic acid (ARA) dietary contents at several dietary eicosapentaenoic acid (EPA) levels on the growth, survival and biochemical composition of gilthead seabream larvae was studied to better define the importance of this fatty acid as a function of EPA. Larvae of 18 days were fed one of the five isonitrogenous and isolipidic microdiets with three different EPA (0.3%, 2% and 4%) and ARA amounts (0.1%, 0.6% and 1.2%). Although a dietary increase in either ARA or EPA alone did not improve survival significantly, the increase in both fatty acids significantly enhanced growth and survival, suggesting an optimum dietary value of EPA:ARA close to 4:1.2. Dietary ARA was more efficiently incorporated into larval tissues than EPA. Increased dietary EPA or ARA contents reduced the incorporation of ARA or EPA into larval lipids, indicating their competition as substrates for different enzymes. The possible negative effect of further elevation of dietary ARA and its competition with EPA for phospholipids synthesis deserves further studies in marine fish larvae.