Stratigraphy and timing of eolianite deposition on Rottnest Island, Western Australia

Over 100 whole-rock amino acid racemization (AAR) ratios from outcrops around Rottnest Island (32.0° S Latitude near Perth) indicate distinct pulses of eolian deposition during the late Quaternary. Whole-rock d-alloisoleucine/l-isoleucine (A/I) ratios from bioclastic carbonate deposits fall into three distinct modal classes or “aminozones.” The oldest, Aminozone E, averages 0.33 ± 0.04 (n = 21). Red palaeosol and thick calcrete generally cap the Aminozone E deposits. A younger Aminozone C averages 0.22 ± 0.03 (n = 63); comprising two submodes at 0.26 ± 0.01 (n = 14) and 0.21 ± 0.02 (n = 49). Multiple dune sets of this interval are interrupted by relatively weak, brown to tan “protosols.” A dense, dark brown rendzina palaeosol caps the Aminozone C succession. Ratios from Holocene dune and marine deposits (“Aminozone A”) center on 0.11 ± 0.02 (n = 15), comprising submodes of 0.13 ± 0.01 (9) and 0.09 ± 0.01 (6). Calibration of A/I averages from Aminozones E and A are provided by U/Th and ¹⁴C radiometric ages of 125,000 yr (marine oxygen isotope stage (MIS) 5e and 2000-6000 ¹⁴C yr B.P. (MIS 1), respectively. The whole-rock A/I results support periodic deposition initiated during MIS 5e, continuing through MIS 5c, and then peaking at the end of MIS 5a, about 70,000-80,000 yr ago. Oceanographic evidence indicates the area was subjected to much colder conditions during MIS 2-4 (10,000 to 70,000 yr ago), greatly slowing the epimerization rate. Eolianite deposition resumed in the mid Holocene (∼6000 yr ago) up to the present. The A/I epimerization pathway constructed from Rottnest Island shows remarkable similarity to that of Bermuda in the North Atlantic (32° N Latitude). These findings suggest that, like Bermuda, the eolian activity on Rottnest occurred primarily during or shortly after interglacial highstands when the shoreline was near the present datum, rather than during glacial lowstands when the coastline was positioned 10-20 km to the west.     

氨基糖酸在药物分子设计与合成中的应用

用非天然的分子实体模拟天然活性分子以提高药物的活性和稳定性.是药物化学中的一个研究热点。氨基糖酸综合了糖和氨基酸结构特征和化学反应特性.是一类新型非天然的多肽模拟物构建模块,广泛的应用在多肽模拟学、组合化学和人工受体分子的构建中。本文综述了近年来氨基糖酸在药物分子设计与合成中的应用进展。     

应用氨基酸分析仪测定血浆中同型胱氨酸含量的研究

根据日立835—50型氨基酸自动分析仪生理体液分析法，以及同型胱氨酸的生理特性，建立测定同型胱氨酸的150min短程序法。经过精密度和准确度试验，重视性好，变异系数小。当同型胱氨酸浓度为4×10－5mol／L时，峰位置和峰面积的变异系数（CV值）分别为0．20％和1．98％（n＝10），明显低于规定技术指标（1％和2．5％）。对1、2、4（×10－4mol／L）浓度的同型胱氨酸加标回收试验，回收率为叶．33～106．67％（n＝9）。本法与原法同时测定大鼠及人体血浆的同型胱氨酸的含量结果基本一致。表明本方法准确、可靠、快速、简便，适用于高脂血症、动脉粥样硬化以及血栓等血浆中同型胱氨酸的测定。本方法样品处理采用任其与空气接触，使血浆中同半型胱氨酸氧化为同型胱氨酸，测定其总同型胱氨酸含量。     

中国对虾(Penaeus orientalis Kishiouys)粗蛋白、氨基酸含量的比较分析

作者对人工养殖中国对虾在不同生长时期、不同性别以及养殖对虾和天然对虾的粗蛋白和氨基酸含量进行了比较分析。得出的结论是:1、粗蛋白含量从8月开始增加,至9月达最高值。赖氨酸、亮氨酸、精氨酸、谷氨酸、甘氨酸和天冬氨酸的含量在8月以后逐月增加,增加幅度较大;其它氨基酸含量随着对虾生长有上升趋势,但不明显;2、无论是养殖对虾,还是天然对虾,雌雄虾之间其氨基酸含量几乎完全相同;3、无论雌雄,养殖对虾和天然对虾的氨基酸含量基本上一致。图6与图7所示甘氨酸和亮氨酸的差异,可能是分析上的随机误差,并非对虾本身差异所带来的不同。     

卤虫杂交品系生化特性的初步研究

选择两性生殖品系（我国山西运城两性生殖品系）的雌体卤虫与孤雌生殖品系（天津塘沽品系）的雄体卤虫，于实验室内获得杂交品系，并对此杂交品系和其亲本品系进行生化特性的比较分析。①同工酶分析的结果表明：杂交F1代雌、雄个体和双亲品系雌、雄个体间的过氧化物酶表现基本相同；F1代的葡萄糖－6－磷酸脱氢酶表现出双亲间的过渡状态；F1代的肌浆蛋白酶带的数量、活性都高于亲本。②进一步对杂交F1代、山西运城两性生殖品系的氨基酸种类和含量做了比较分析，结果表明：杂交品系的氨基酸总含量明显高于其亲本，且含有单一亲本所不具有的氨基酸（如胱氨酸）组成。本实验结果显示，通过杂交手段可显著提高卤虫遗传变异水平，并且是选择高卤虫营养品系的手段之一。     

海蓬子种子营养成分分析及制备共轭亚油酸的研究

分析了盐生植物——海蓬子种子的营养成分，并利用其种子油制备共轭亚油酸。研究结果表明：海蓬子种子蛋白质含量为42．59％，高于大豆和其它蛋白质植物；氨基酸组分较齐全，优于鸡蛋蛋白。种子油不饱和脂肪酸含量高，为89．77％，其中亚油酸为73．63％，组成类似红花油，有很高的营养保健功能。用种子油制备共轭亚油酸，亚油酸转化为共轭亚油酸的转化率达到86．07％，共轭亚油酸含量将近70％，海蓬子种子油可制成优质食用油，也可作为制备共轭亚油酸的原料。     

中华绒螯蟹三倍体群体早期生长及营养的研究

将中华绒螯蟹三倍体大眼幼体群体 (三倍体率 64.38% )在池塘中养殖 ,对其早期生长及营养进行测定。结果表明 ,从三倍体群体自身的生长状况看 ,放养后 68— 78天是整个测量期间三倍体群体生长最快的阶段 ,其中壳长增长显著 (P <0 .0 5 ) ,壳宽和体重的增加极显著 (P <0 .0 1 )。与二倍体群体相比 ,放养后 68— 1 0 6天 ,三倍体群体在壳长、壳宽、体重上都表现出明显的生长优势 (P <0 .0 1 )。三倍体幼蟹蟹体氨基酸总量高于正常二倍体幼蟹 ,必需氨基酸中苏氨酸、苯丙氨酸、缬氨酸、亮氨酸、精氨酸、异亮氨酸、组氨酸和赖氨酸的含量高于二倍体 ,而蛋氨酸的含量则低于二倍体幼蟹。蟹体中不饱和脂肪酸所占比例三倍体幼蟹低于正常二倍体 ,EPA、DHA及多不饱和脂肪酸所占的比例也低于二倍体。结果表明 ,三倍体幼蟹的生长比正常二倍体具有优势 ,并且在营养组成上也和二倍体有所差异。     

Evaluation of nutrient components of Bangia sp.

General nutrient components including moisture, ash, crude protein, lipid and carbohydrate, inorganic elements, photosynthetic pigments, amino acids and fatty acids of Bangia sp. were analyzed and compared with Porphyra yezoensis. The results indicated that the content of protein, total amino acids and free amino acids accounted for 47.2% , 42.6% and 3.3% in dried Bangia sp. , respectively, all essential amino acids were present in relatively high levels and desirable composition. Lipid was 1.8%, in which the eicosapentaenoic acid (EPA) reached 50.5% . In per 100 g dried material, the content of chlorophyll, carotenoids, phycoerythrin and phycocyanin accounted for 766, 208, 4 600 and 2963 mg, respectively. Inorganic elements necessary for human body were found to be abundant in Bangia sp. The results showed that the nutritive value of Bangia sp. was the highest among algae reported so far, and the industry of Bangia sp. was provided with significant economic importance and developing potential.     

泥蚶血淋巴营养成分的研究

本文利用氨基酸自动分析仪和气相色谱分析仪对泥蚶血淋巴中的脂肪酸和氨基酸进行了分析测定．研究结果表明：泥蚶血淋巴含有脂肪酸和氨基酸各18种，脂肪酸总含量为0．395mg／g，其中不饱和脂肪酸含量高达0．215mg／g，约占脂肪酸总量的54．2％；氨基酸总含量为1、68％，其中必需氨基酸占氨基酸总量的39．88％，呈鲜味游离氨基酸和呈甘味游离氨基酸占泥蚶血淋巴氨基酸总量的47．02％．     

The Importance of Posidonia oceanica and Cymodocea nodosa as Contributors of Free Amino Acids in Water and Sediment of Seagrass Beds

Abstract. Dissolved free amino acids (DFAA) were measured in sediment porewater and overlying sea water in seagrass beds of Posidonia oceanica and Cymodocea nodosa at a water depth of 8–10 m in Corsica, France. In the sea water, DFAA concentrations from 0.5 to 1.9μM were found. Lowest concentrations occurred in the afternoon in surface water samples, while higher concentrations were measured in morning surface samples and in all bottom samples. The most abundant amino acids were serine, glycine, and alanine. In the sediment, the upper 4cm contained the highest concentrations of DFAA (177nmol cm^-3 or 367 μM), while lower concentrations (<50nmol cm^-3 or 104 μM) prevailed deeper in the sediment. Glycine, glutamic acid, alanine, and β-alanine were the major components of the DFAA. The photosynthetic activity of the seagrasses influenced sediment porewater pools of DFAA. When a Posidonia bed was covered with a black polyethylene shield, the interstitial amino acids were reduced at a rate of 16nmol cm^-2 h^-1 (0-10cm depth). Conversely, extended daylight (floodlight) increased the DFAA pool in sediment depths below 4 cm. Free amino acids were released to the overlying sea water from both seagrass sediment and individual shoots, the rates being highest in the dark. The present investigation indicates that a substantial portion of the N-cycling of the seagrass sediment includes free amino acids.