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991.
Legionella pneumophila is the causative agent of Legionnaires’ disease, a serious form of pneumonia. Its macrophage infectivity potentiator (Mip), a member of a highly conserved family of FK506-binding proteins (FKBPs), plays a major role in the proliferation of the gram-negative bacterium in host organisms. In this work, we test our library of >1000 FKBP-focused ligands for inhibition of LpMip. The [4.3.1]-bicyclic sulfonamide turned out as a highly preferred scaffold and provided the most potent LpMip inhibitors known so far. Selected compounds were non-toxic to human cells, displayed antibacterial activity and block bacterial proliferation in cellular infection-assays as well as infectivity in human lung tissue explants. The results confirm [4.3.1]-bicyclic sulfonamides as anti-legionellal agents, although their anti-infective properties cannot be explained by inhibition of LpMip alone.  相似文献   
992.
Today, the need for quality wool suitable for worsted fabric production in the world is mainly met by Australian merino wool. In Turkey, which has a significant sheep population, in addition to domestic breeds, approximately 10% of the total sheep population (around four million head) is composed of merino cross breeds. However, the fleece quality is far from meeting Australian merino wool standards. Therefore, the aim of this study is to ensure a merino herd with high-quality wool in Turkey. For this aim, by carrying out field studies in the Thrace region of Turkey where Turkish Merino sheep are widely bred, sheep with fleece that can meet the demands of the worsted industry were determined. As a result of field studies in which thousands of sheep were examined, it was determined that 43 female and 10 male sheep had fleece that would meet these standards. Then the breeders of the sheep, which had quality fleece, were persuaded and these sheep were purchased, and “Turkey's wool-oriented Turkish (Karacabey) Merino Herd” consisting of 30 sheep and three rams was formed in the farm of Tekirdağ Namık Kemal University. In the second part of this study, a 100% wool fabric produced by using Australian merino was taken as a reference and it was aimed to produce the same fabric from Turkish merino wool. For this aim, the wool-oriented Turkish Merino herd, which was bred at the university farm for 1 year, was shorn in May 2022. Then, Turkish and Australian merino wools were first converted into worsted yarn and then into woven fabric. The results of mechanical (tensile strength, pilling, abrasion resistance, felting shrinkage, Hofmann dimensional change, bending stiffness) and dyeability (dye-uptake, CIE L*a*b* and colour yield (K/S) values; washing, rubbing and light fastness values) properties of fabrics produced from Turkish and Australian merino wool is presented.  相似文献   
993.
乳酸菌在食品及食品发酵行业具有广泛的应用,其中以乳酸菌发酵酸浆作为凝固剂的酸浆豆腐已逐渐成为人们关注的热点。酸浆豆腐发酵过程中以乳酸菌为优势菌,在酸浆豆腐点浆时,需在75℃以上高温下进行。普通乳酸菌无法耐受此温度且大量失活,影响产品的后熟。为了开发耐高温乳酸菌,以课题组从云南建水豆腐酸浆中分离的菌株为出发菌,通过紫外诱变的方式,温度梯度筛选获得4株耐高温产酸性能好的菌株。诱变获得4株菌均可在75℃耐高温30 min并保持较好的活性和产酸效果。研究所得突变菌株相比原始菌株均具有更好的耐热性和产酸性。其中HCUL 1.1801-1912Z活性最强、产酸能力最好,为4株菌中最优菌株,将该菌株用于发酵生产酸浆豆腐,将显著提高乳酸菌在豆腐中的活性和豆腐的品质。  相似文献   
994.
995.
The design of distinctive chemical synthesis strategies aims for the most efficient routes towards versatile compounds in drug target studies. Here, we establish a powerful hybrid synthetic approach of total chemical and chemoenzymatic synthesis to efficiently obtain various 7-deoxy-sedoheptulose (7dSh, 1 ) analogues, unique C7 sugars, for structure-activity relationship studies. 7dSh ( 1 ) is a rare microbial sugar with in planta herbicidal activity. As natural antimetabolite of 3-dehydroquinate synthase (DHQS), 7dSh ( 1 ) inhibits the shikimate pathway, which is essential for the synthesis of aromatic amino acids in bacteria, fungi, and plants, but absent in mammals. As glyphosate, the most used chemical herbicide faces restrictions worldwide, DHQS has gained more attention as valid target of herbicides and antimicrobial agents. In vitro and in vivo analyses of the C7-deoxysugars confirm DHQS as enzymatic target, highlight the crucial role of uptake for inhibition and add molecular aspects to target mechanism studies of C7-sugars as our contribution to global efforts for alternative weed-control strategies.  相似文献   
996.
This study aimed to determine the chemical properties (fatty acid composition, oil content, sterol and tocopherol compositions) of the oils extracted from the seeds of safflower (Dinçer, Remzibey, Balci, Linas, Yenice, Olas) varieties harvested in different periods from flowering to ripening period. In parallel with the increase of harvest time, the humidity rate decreased, while the oil ratios increased. It was determined that palmitic (16:0) and stearic (18:0) acids, which are significant saturated fatty acids, and oleic (18:1) and linoleic (18:2) acids, which are unsaturated fatty acids, are quite high in the oils of all safflower varieties. These fatty acids showed significant changes from the first harvest to the last harvest. The total saturated fatty acid ratios decreased, while the amount of unsaturated fatty acids increased as the maturation progressed. The first and latest harvest samples of Dinçer, Remzibey, Balcı, Linas, Yenice, Olas cultivars were selected and their sterol and tocopherol compositions were examined. The highest level of sterol in all cultivars was β-sitosterol and the amount of sterols decreased towards full maturity. It was determined that α-tocopherol was the dominant tocopherol found in the safflower oils and the amount of tocopherol increased towards full maturity.  相似文献   
997.
介绍了孔结构优化对渣油加氢脱金属剂的影响。为提高脱金属剂的脱金属活性以及长周期运行稳定性,首先以工业参比失活脱金属剂的失活行为做指导,提出自制脱金属剂设计优化思路;随后在脱金属剂载体制备过程中,加入薄膜胶溶剂和高聚合度扩孔剂并调节水含量成功制备出具有更多大孔分布、更大孔容的载体。与工业参比脱金属剂相比,自制脱金属剂载体具有更多的300 nm孔分布,孔容提高约50%。自制脱金属剂对镍、钒总脱除能力比工业参比脱金属剂高2%~3%,并具有优异的长周期运转稳定性。自制脱金属剂有着更好的渣油加氢反应性能和稳定性,有较好的应用前景。  相似文献   
998.
基于气相色谱法和超高效液相色谱-四极杆-飞行时间串联质谱法探究饲喂裂殖藻粉(Schizochytrium spp.)对山羊乳脂肪酸组成及全脂质组成的影响,并与市售纯牛乳和二十二碳六烯酸(docosahexaenoic acid,DHA)牛乳进行差异性分析。结果表明,山羊乳脂肪含量显著高于牛乳,肉豆蔻酸、棕榈酸和油酸是乳中主要的脂肪酸组成。饲喂裂殖藻粉能显著增加山羊乳中DHA含量。甘油三酯是2种乳中主要的脂质成分,山羊乳中磷脂含量显著高于牛乳。DHA在乳品脂质中主要以甘油酯型DHA形式存在,山羊乳较牛乳含更丰富的磷脂型DHA。裂殖藻粉添加量50 g/d为山羊乳中DHA富集的最佳添加量。通过在日粮中添加DHA原料,能够进一步提高山羊乳的营养价值,解决目前膳食DHA来源单一的问题。本研究为婴幼儿配方奶粉及富DHA功能性乳脂产品的开发和营养调控提供有力的理论依据和参考,并为乳制品类型的鉴定提供方法与数据基础。  相似文献   
999.
6-姜酚是生姜辣味物质姜酚的主要成分,具有抗肿瘤、抗炎、抗氧化、降血糖、降血脂、降血压、防治结肠炎等多种健康效应。然而,由于存在水溶性低、胃肠道稳定性差、体内代谢速率快、非靶标吸收部位释放、刺激性苦辣味等问题,使6-姜酚经口摄入后的健康效应发挥受限。本文综述了6-姜酚抗癌、抗炎、降血脂、防控心脑血管疾病、治疗胃肠道疾病等健康效应及作用机制。基于6-姜酚在胃肠道的吸收、在体循环中的分布、代谢和排泄及其在上、下消化道的代谢过程的研究进展,对当前针对6-姜酚设计的口服增效靶向递送体系研究现状进行总结,并阐释其增强健康效应的调控机制和功效提升策略的设计原理。本综述可为6-姜酚口服靶向递送体系的设计及其增效作用机制的研究提供理论指导,并为其功能食品制品的开发提供科学依据。  相似文献   
1000.
Microwave-assisted hydrothermal synthesis of aluminum (Al)-doped TiO2 (ALT) and niobium (Nb)-doped TiO2 (NBT) nanoparticles were carried out. Investigations were performed to examine the crystallinity, vibrational modes, surface morphology, and composition using X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS), respectively. The XRD study indicated the higher crystallinity of the ALT particles compared to the Al and Nb-doped TiO2 (ALNBT) particles, and only the presence of the anatase phase was observed in all samples. As a result of doping, the Raman mode at ∼147 cm−1 is found to be shifted toward a higher wavenumber for both samples. SEM analysis showed the spherical morphology of ALT and NBT nanoparticles. The elemental composition peaks of Al, titanium, Nb, and oxygen were noticed by EDS measurements. Furthermore, both prepared nanoparticles were used as photocatalytic materials. The Nb and Al-doped samples showed an improvement in the photocatalysis response in relation to the pure TiO2 sample, in which Al-doped sample was able to decolorize 100% of rhodamine B in 75 min of analysis.  相似文献   
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