三角鲂和长春鳊肌肉营养成分分析与品质评价

用常规方法测定、分析了三角鲂(Megalobrama tarminalis)和长春鳊(Parabramis pekinensis肌肉中营养成分组成与含量.结果显示,三角鲂肌肉蛋白质、脂肪含量分别为18.19％和3.06％,长春鳊肌肉蛋白质、脂肪含量分别为19.38％和2.89％.三角鲂和长春鳊肌肉中均检测出18种氨基酸,其中包括了8种人体必需氨基酸.三角鲂肌肉中氨基酸总量为76.27％,其中,8种人体必需氨基酸含量为32.17％,占氨基酸总量的42.18％;长春鳊肌肉中氨基酸总量为77.60％,其中,8种人体必需氨基酸含量为31.70％,占氨基酸总量的40.85％.必需氨基酸的构成比例基本符合FAO/WHO的标准.三角鲂肌肉中限制性氨基酸主要为甲硫氨酸加胱氨酸,必需氨基酸指数为63.55,4种呈味氨基酸为氨基酸总量的32.81％;长春鳊肌肉中限制性氨基酸主要为色氨酸,必需氨基酸指数为66.81,4种呈味氨基酸为氨基酸总量的33.80％.脂肪酸中二十碳五烯酸(EPA)与二十二碳六烯酸(DHA)含量均较高,三角鲂为7.96％,长春鳊为3.11％.矿物元素比值合理.以上分析表明,三角鲂和长春鳊均为营养价值、经济价值都较高的优质鱼类,相比而言,三角鲂肌肉脂肪、脂肪酸含量和质量更优,而长春鳊肌肉在蛋白质、氨基酸组成与含量方面更优.     

大杯香菇辐射新株系各类氨基酸的遗传主成分分析

对大杯香菇辐射选育新株系的各类氨基酸总量进行了遗传主成分分析。结果表明,变异系数最大的为硫氨基酸总量,达到13．39％;其次为儿童氨基酸总量,变异系数为7．00％;其它变异系数较小分别为甜味氨基酸总量、芳香族氨基酸总量、必需氨基酸总量、支链氨基酸总量和鲜味氨基酸总量为5．69％、5．64％、5．19％、5．24％和5．06％;在相关性上,鲜味氨基酸总量与甜味氨基酸总量、支链氨基酸总量、芳香族氨基酸总量、儿童氨基酸总量和必需氨基酸总量是呈极显著和显著的正相关,甜味氨基酸总量与支链氨基酸总量、儿童氨基酸总量和芳香族氨基酸总量呈极显著和显著的正相关,硫氨基酸总量与儿童氨基酸总量呈极显著负相关,与必需氨基酸总量是呈极显著正相关;支链氨基酸总量与芳香族氨基酸总量、必需氨基酸总量是呈极显著,与儿童氨基酸总量呈显著正相关;芳香族氨基酸总量与儿童氨基酸总量和必需氨基酸总量是呈极显著和显著的正相关;主成分分析结果表明,前4个特征根在7个特征根中累计贡献率达97．14％,也就是前4个主成分对变异的贡献率达96．07％。在各类氨基酸总量指标选择上,首先对变异大的各类氨基酸总量进行选择是及其重要的。在辐射选育新株系选择时,应注意选择大杯香菇中硫氨基酸总量高的新株系。     

中华鳖生化组成的分析：Ⅲ.肌肉氨基酸的组成

对中华鳖的稚鳖、一龄鳖、二龄鳖和三龄鳖肌肉中的氨基酸的组成进行了分析,结果表明：肌肉中必需氨基酸的含量约占氨基酸总量的４９．４８％,谷氨酸的含量很高,为氨基酸总量的１５％以上。在分析与比较的基础上评价了中华鳖在氨基酸方面的营养价值,为中华鳖配合饲料的开发提出了理论上的依据。     

黄粉虫蛹的营养成分分析

采用现代分析技术手段对黄粉虫Tenebrio molitor（L．）蛹的营养成分进行分析,结果表明：其蛋白质、粗脂肪、碳水化合物及灰分含量分别为鲜重的16．8％、7．6％、1．2％、1．4％,其氨基酸和胆固醇含量分别为18.7mg／g和0．4mg／g;含有7种人体必需氨基酸,其必需氨基酸占总氨基酸含量的44．40％,必需氨基酸与非必需氨基酸含量的比值为79.8％,第一限制性氨基酸为含硫氨基酸,即蛋氨酸和胱氨酸;同时,其不饱和脂肪酸与必需脂肪酸分别占总脂肪的73．9％和24．1％,特别是油酸和亚油酸含量较高,分别达49．8％和23．4％：另外,该昆虫还含有K、Ca、Mg、Fe、Zn、Cu、Mn等多种矿物质和微量元素。     

珠子参地上部分氨基酸测定及营养评价

对珠子参茎、叶、花的氨基酸组成与含量进行测定和营养评价分析.结果表明,珠子参茎、叶、花中均含有17种常见氨基酸,氨基酸总量分别为3.73％,14.80％和8.72％;珠子参的茎中必需氨基酸与总氨基酸的比值(E/T)为0.39,必需氨基酸与非必需氨基酸的比值(E/N)为0.64,叶中E/T为0.41,E/N为o.71,花中E/T为0.39,E/N为0.63,氨基酸配比较为合理;珠子参茎、叶、花中蛋氨酸+胱氨酸均为第一限制氨基酸;珠子参茎、叶、花中均含有γ-氨基丁酸,含量分别为0.12％,0.26％和0.16％,叶片中γ-氨基丁酸的含量最高.     

软枣猕猴桃氨基酸分析

本文应用日立—835型氨基酸自动分析仪测定了软枣猕猴桃不同部位的氨基酸含量。结果表明:软枣猕猴桃根、叶中均含有16种以上氨基酸,其中有8种人体必需氨基酸;果实中含有14种氨基酸,其中有6种必需氨基酸,精氯酸含量最高,其次为赖氨酸、亮氨酸、丙氨酸和天门冬氨酸。     

丁(鱼岁)的含肉率及其营养价值的分析

报道了丁Gui的含肉率及鱼肉生化成分,并对其营养价值做了综合评价。丁Gui含肉率达73.59％,鱼肉蛋白质含量为19．73％,脂肪含量为1．29％。17种氨基酸总含量为18．13％,其中7种必需氨基酸总量为7．04％。丁Gui肌肉所含人体必需氨基酸占氨基酸总量的百分比高于WHO／FAO提出的标准。必需氨基酸指数为74．38。     

双孢蘑菇子实体营养成分分析

测定了双孢蘑菇子实体中氨基酸、矿质元素、多糖、粗蛋白、粗脂肪、灰分、粗纤维、核苷酸、维生素C和SOD等含量。结果表明,粗蛋白含量为37．86％,在测定的18种氨基酸中含有17种氨基酸,8种必须氨基酸含量占氨基酸总量的42．30％;必需氨基酸与非必需氨基酸比值（E／N）为0．73。还含有丰富的多糖、纤维素、超氧化物歧化酶（SOD）和核苷酸类物质。     

基于游离氨基酸的组分及特征比较四种食用菌与四种果蔬的营养与风味特征

为科学评价食用菌与果蔬两类食材的营养特征与口感风味,本研究选取4种常见食用菌（金针菇、斑玉蕈、香菇、双孢蘑菇）和4种常见果蔬（苹果、香蕉、胡萝卜、番茄）,采用氨基酸自动分析仪测定其游离氨基酸,系统比较了两类食材的游离氨基酸组分比例及呈味特征。主成分和聚类分析表明 4种食用菌和4种果蔬显著分为两类,食用菌类游离氨基酸总量平均是果蔬类的3倍以上,4种食用菌中各游离氨基酸的比例均衡。4种食用菌的必需氨基酸/(必需氨基酸+非必需氨基酸)在40%左右,必需氨基酸/非必需氨基酸接近或大于60%,均接近理想值。4种食用菌所含的呈味氨基酸（鲜味、甜味、芳香族、苦味）均是4种果蔬的2倍以上,TAV值最显著的是：谷氨酸、苯丙氨酸、甘氨酸、苏氨酸、组氨酸、赖氨酸、缬氨酸、精氨酸和丙氨酸。这些氨基酸分属在五大氨基酸家族,在食用菌与果蔬中代谢途径相同;只有赖氨酸在二者中的合成途径不同。结果表明供试的食用菌比果蔬有优质的氨基酸比例和丰富的呈味组分,此差异体现在众多氨基酸的代谢层面,而非个别氨基酸导致。     

Accq.Tag法测定氨基酸口服液的氨基酸含量

采用AccQ .Tag法对氨基酸口服液中游离氨基酸和牛磺酸含量进行了分离测定。产品中氨基酸总量达 85mg/ml以上 ,共 1 3种氨基酸。必需氨基酸与非必需氨基酸比例为 2 .2 0～ 2 .50∶1 ,支 /芳比为 2 .30～ 2 .55∶1 .配方接近于FAO氨基酸比例模式 ,以FAO氨基酸模式及化学评分评价了该制剂的营养价值 ,基本上不存在限制氨基酸 ,化学评分均在 90分以上。     

Compartmentation and exchangeability of brain amino acids: evidence from studies of transport into tissue slices.

Compartmentation of the free amino acid pool of brain slices was investigated by measuring the approach to isotopic equilibrium between tissue and medium when slices were incubated with traces of radioactive amino acids. Trace quantities were used to minimize the effects of uptake, which could make the detection of slowly equilibrating pools difficult by greatly increasing tissue amino acid levels. Small, sequestered compartments were found. After 2 h in 20 vol of glucose-containing, oxygenated medium, the nonequilibrating compartments for lysine, leucine, tyrosine, histidine, valine, and threonine were 41, 20, 17, 16, 11, and 6% of their final tissue concentrations, respectively. The data for rapidly metabolized, nonessential, amino acids were more difficult to interpret. Considerable mixing of incoming glutamic and aspartic acids with their endogenous pools was observed and tissue glycine reached isotopic equilibrium within 1 h. With higher concentrations of amino acids, equilibration was complete in 30 min with 2 mm glycine in the medium; 83% in 30 min with 2 mm glutamic acid, and 95% in 60 min with 5 mm glutamic acid in the medium. The amino acid composition of protein free extracts of slices and medium was determined. During incubation, despite a large efflux of amino acids into the medium, most tissue amino acids remained close to their initial concentrations. Net increases in essential amino acids were accounted for by the breakdown of 0.7% of total tissue protein during the first hour and 0.3% during the second hour of incubation.     

Biochemical Changes in Terminal Root Galls Caused by an Ectoparasitic Nematode,Longidorus africanus: Amino Acids

The amino acids of terminal root galls caused by Longidorus africanus on bur marigold (Bidens tripartita L.) and grapevine (Vitis vinifera L.) were studied. The galled roots of bur marigold contained 73% more cell-wall protein and 184% more free amino acids. The main changes among the free amino acids of the galled tissue were a large increase (1900%) in proline and a decrease in aspartic acid (56%) compared with the respective check tissue. Hydroxyproline decreased in the wall protein fraction from 5.6% in the healthy tissue to 3.6% in the infected tissue.Percent of hydroxyproline in total amino acids of the wall protein fraction of grapevine roots decreased from 0.7% in the healthy tissue to 0.3% in the galled tissue, and total proteins of this fraction decreased from 9.5 mg to 4.5 rag, respectively. Total protein in the protoplasmic fraction also decreased from 3.0 mg in healthy to 1.0 mg in infected roots. No change was noticed in total proteins in the free amino acids fraction but free proline decreased 40% in the infected roots.The relationship of these differences to the specific reactions of the hosts to nematode feeding is discussed.     

Quantitative analysis of 17 amino acids in the connective tissue of patients with pelvic organ prolapse using capillary electrophoresis-tandem mass spectrometry

The simultaneous determination of 17 amino acids in connective tissue using capillary electrophoresis is described in this study. Separation was carried out on a fused silica capillary column (80 cm x 50 mm i.d.) with 1M formic acid as the running electrolyte. The detection was conducted on a mass spectrometer by selective reaction monitoring (SRM) mode via an electrospray ionization source. Tissue samples were prepared by reduction and acid hydrolysis to extract amino acids; over 84.3% recovery was seen for all compounds. The method allowed for sensitive, reproducible, and reliable quantification, and all 17 amino acids were separated using this method. Good linearity over the investigated concentration ranges was observed, with values of R higher than 0.993 for all the analytes. Precision and accuracy examined at three concentration levels ranged from 0.2% to 19.5% and 84.1% to 120.0%, respectively. Matrix effects were also tested and ranged from -9.1% to 15.4%. The validated method was applied to the quantitation of 17 amino acids in pelvic connective tissue of pelvic organ prolapsed patients. Methionine, glutamine, and histidine were significantly higher in the experimental patients compared to the controls. This suggests that changes in the amino acid concentrations within the connective tissue could be a factor in the genesis of pelvic organ prolapse. Therefore, this method is potentially applicable for amino acid analysis in tissue, providing a more complete understanding of pelvic organ prolapse.     

皱肋文蛤氨基酸含量及脂肪酸组成分析

测定了皱肋文蛤(Meretrix lyrata)软体部分的氨基酸含量与脂肪酸组成.共检出17种氨基酸,总含量为软体部干重的52.26%;4种呈味氨基酸(天门冬氨酸、谷氨酸、甘氨酸和丙氨酸)的含量为22.07%,占氨基酸总量的42.23%;必需氨基酸(EAA)总含量为20.72%,其必需氨基酸的构成比例基本符合FAO/W...     

新疆阿魏菇与杏鲍菇中氨基酸含量的分析研究

对新疆阿魏菇与杏鲍菇的氨基酸成分进行系统分析,结果显示新疆本地的阿魏菇和杏鲍菇中17种氨基酸含量丰富,种类齐全,阿魏菇中氨基酸总量为16.80%高于杏鲍菇中氨基酸总量(14.34%);两种菇中必需氨基酸含量(EAA)占总氨基酸含量的比例分别为34.72%和37.92%。新疆阿魏菇与杏鲍菇种富含人体必需的氨基酸,可作为饮食氨基酸来源的重要补充。     

Infusion of amino acids decreases the hyperglycaemic effect of per- and postoperative glucose infusion: an experimental study in the rabbit

The effects on blood glucose concentration of 10% glucose with amino acid solution at low (18%) and high (25%) concentration of branched chain amino acids were studied, two days after laparotomy in fasted rabbits. During the whole study period, saline infusion was associated with normoglycaemia. Among the other infusion combinations peroperative infusion of amino acid solution high in branched chain amino acids with 10% glucose was the least hyperglycaemic. An amino acid solution low in branched chain amino acids with 10% glucose had the lowest hyperglycaemic effect 24 hours postoperatively. After 48 hours an infusion of 10% glucose produced the weakest hyperglycaemia. In preoperatively and 24 hours postoperatively 10% glucose was more hyperglycaemic than 10% glucose with the two amino acid solutions. After 24 and 48 hours, infusion of 10% glucose with amino acids high in branched chain amino acids was more hyperglycaemic than 10% glucose with amino acids low in branched chain amino acids.     

Amino acid and glucose uptake by rat brown adipose tissue. Effect of cold-exposure and acclimation.

The net uptake/release of glucose, lactate and amino acids from the bloodstream by the interscapular brown adipose tissue of control, cold-exposed and cold-acclimated rats was estimated by measurement of arteriovenous differences in their concentrations. In the control animals amino acids contributed little to the overall energetic needs of the tissue; glucose uptake was more than compensated by lactate efflux. Cold-exposure resulted in an enhancement of amino acid utilization and of glucose uptake, with high lactate efflux. There was a net glycine and proline efflux that partly compensated the positive nitrogen balance of the tissue; amino acids accounted for about one-third of the energy supplied by glucose to the tissue. Cold-acclimation resulted in a very high increase in glucose uptake, with a parallel decrease in lactate efflux and amino acid consumption. Branched-chain amino acids, however, were more actively utilized. This was related with a much higher alanine efflux, in addition to that of glycine and proline. It is suggested that most of the glucose used during cold-exposure is returned to the bloodstream as lactate under conditions of active lipid utilization, amino acids contributing their skeletons largely in anaplerotic pathways. On the other hand, cold-acclimation resulted in an important enhancement of glucose utilization, with lowered amino acid oxidation. Amino acids are thus used as metabolic substrates by the brown adipose tissue of rats under conditions of relatively scarce substrate availability, but mainly as anaplerotic substrates, in parallel to glucose. Cold-acclimation results in a shift of the main substrates used in thermogenesis from lipid to glucose, with a much lower need for amino acids.     

Determination of amino acid tissue concentrations by microdialysis: method evaluation and relation to plasma values

Summary. Microdialysis is an in vivo technique to monitor tissue concentrations of low molecular weight substances by means of a continuously perfused artificial capillary with a semipermeable membrane placed into the region of interest. The suitability of microdialysis to determine tissue concentrations of amino acids was evaluated in vitro by placing the catheter into Ringer buffer or into a plasma protein (50 g/l) solution containing 32 different amino acids (150 μmol/l each). All amino acids tested crossed freely the microdialysis membrane with recoveries close to 100%. Microdialysis fluid was sampled from subcutaneous tissue of five newborns and amino acid content analysed. Total and non protein bound amino acids were determined in the patients plasma by acid precipitation or ultrafiltration, respectively. Mean subcutaneous tissue concentrations were lower as compared to plasma for taurine, serine, alanine, aspartate, glutamate and ornithine and higher for valine, isoleucine, leucine, methionine, phenylalanine, tyrosine and arginine, indicating net uptake or release of amino acids from subcutaneous tissue. Thus, microdialysis offers a convenient and minimal invasive way to study tissue amino acid composition and appears to be a promising analytical tool for the study of amino acid metabolism in vivo. Received August 7, 2000 Accepted January 7, 2001     

The effect of the coded amino acids on meso- and ectodermal tissue development in organotypic culture

The effect of L-amino acids was investigated in organotypic tissue culture ofmesodermal tissue (spleen, myocardium) and ectodermal tissue (brain cortex) in mature rats. The low hydrophobic amino acids: asparagine, hystidine, serine, lysine, arginine and glutamine acid, induced the proliferation stimulation. The high hydrophobic amino acids had both the apoptose effect (spleen) and no effect at all (myocardium). The proliferation stimulation occurred in the ectodermal tissue under the effect of the high hydrophobic amino acids (asparagines acid, valine, threonine, methionine, leucine, isoleucine), whereas the low hydrophobic amino acids had no effect on the nervous tissue development. The combination of two amino acids one of which stimulated and another one inhibited the explant growth zone (or was not active in myocardium) lead to an increase of the stimulatory effect in meso- and ectodermal tissue. The amino acid modulated properties can be taken in consideration in synthesis of new regulatory peptides.     

中药鳖甲及两种炮制品的氨基酸营养学

本文报导了鳖甲及其炮制品的氨基酸营养分析情况。结果表明,生品含17种游离氨基酸,传统炮制品含15种游离氨基酸,食用菌炮制品含16种游离氨基酸,且生品总氨基酸的含量明显高于炮制品,经盐酸水解后,炮制前后的样品均测得17种氨基酸,生品的含量略高于炮制品,炮制品前后样品中所测游离氨基酸和水解后氨基酸均含有8种人体必需氨基酸。