明党参中胆碱的分离鉴定和不同采收期的含量测定

利用雷纳克（Ｒｅｉｎｅｃｋｅ’ｓ）盐法,从明党参中首次分得胆碱,用红外光谱进行鉴定,并对粉沙参,七、八、九月采收的明党参中胆碱的含量进行了比较分析。结果表明,八月采收的明党参中胆碱含量最高（４７．１６１ｍｇ／１００ｇ）,其次为粉沙参（３３．１９８ｍｇ／１００ｇ）及九月采收的明党参（３２．４０４ｍｇ／１００ｇ）,七月采收的明党参胆碱含量较低（２３．４７９ｍｇ／１００ｇ）。同时与党参进行了参照测定。     

体外乳酸菌素促双歧杆菌生长实验初步观察

目的 在体外观察乳酸菌素是否有促双歧杆菌生长的作用。方法 将浓度为１００ｍｇ／ｍｌ、１０ｍｇ／ｍｌ、１ｍｇ／ｍｌ的乳酸菌素液按三角形对等距离分别滴种在接种了双歧杆菌（１０＾６ＣＦ／ｍｌ）的ＢＨＩ培养基上,然后置３５℃厌氧箱培养２ｄ后观察细菌生长情况。结果 不同浓度的乳酸菌素液促进双歧杆菌生长能力不同。浓度为１００ｍｇ／ｍｌ、１０ｍｇ／ｍｌ、１ｍｇ／ｍｌ的乳酸菌素液促双歧杆菌生长的阳性率（％）分别为：９６．７、５６．７、１．０。经统计学秩和检验方法将３种浓度乳酸菌素液促双歧杆菌生长作用进行两两比较得知：１００ｍｇ／ｍｌ与１０ｍｇ／ｍｌ,１００ｍｇ／ｍｌ与１ｍｇ／ｍｌ之间Ｐ〈０．０１,１０ｍｇ／ｍｌ与１ｍｇ／ｍｌ比较Ｐ〈０．０５。结论 乳酸菌素有促进益生菌－－双歧杆生长的作用,而且与其浓度高低有极密切关系,高浓度的     

山东省部分地区献血者血浆牛磺酸含量测定

对１３４名献血者的血浆牛磺酸（ＴＡＵ）含量进行了测定,其平均值为（２．２３±０．６３）ｍｇ／１００ｍｌ。实验表明：多次与首次献血者之间以及男女性别之间的血浆ＴＡＵ含量均无显著性差异（ｐ＞０．０５）,而不同血型献血者之间的血浆ＴＡＵ含量存在着差异（ｐ＜０．０５）。     

苦豆子游离氨基酸的成份测定

本文分析和鉴定了苦豆子中游离氨基酸的成份,测定出１６种游离氨基酸,总量为１６４．５２μｇ／１００ｍｇ,其中谷氨酸含量最高为４７．６８μｇ／１００ｍｇ,蛋氨酸含量最低为０．２０μｇ／１００ｍｇ,人体必须氨基酸有７种,占游离氨基酸总量的１７．３３％。     

氨基酸显色剂茚三酮试剂的研究（二）──不同浓度显色剂对氨基酸含量的影响

氨基酸显色剂是氨基酸分析的重要试剂之一。主要成份是茚三酮、二甲亚砜、还原剂、氢氧化锂等有机试剂合成的氨基酸显色剂（以下称显色剂）。目前这种显色剂依赖从国外进口,由于受价格、进口周期及有效期限等诸多因素的影响,使之远远不能满足国内用户的需要,为适应国内用户的需要,进一步论证自制显色剂的可行性和可靠性,确定显色剂的最佳配方,本项目对自制显色剂的存放时间［１］、不同浓度显色剂、以及显色剂光学试验等项指标进行了全面系统地分析比较,本研究观察了１００ｍｌ溶液中显色剂含量分别为５ｍｇ、１０ｍｇ、１５ｍｇ、２０ｍｇ、２５ｍｇ等不同浓度的自制和进口显色剂对氨基酸含量的影响,结果表明,当显色剂的浓度为１５ｍｇ／１００ｍｌ时,氨基酸可出现最大峰值、测定所得氨基酸浓度显著高于２０、２５ｍｇ／１００ｍｌ和５、１０ｍｇ／１００ｍｌ所得的结果。提示氨基酸显色剂不但与存放时间有关,而且与其浓度关系密切的有关理论：     

墨龙系列酒中氨基酸组分评价

采用岛津Ｌ_（ｃ－ｂＡ）高效液相色谱仪测定墨龙醇、麒麟玉液、猕猴桃乳酒中１３种氨基酸总量分别为５０８．２、４９１．７、２４７．４ｍｇ／１００ｍｌ,其中１２种人体必需、半必需氨基酸与１０种药效氨基酸的含量和分别占总含量的５９．７％、６５．５％、７６．２％和４３．８％、４８．１％、４７．５％。     

广东眼镜蛇蛇胆的鉴别及质量控制的研究Ⅳ：广东眼镜蛇蛇胆中牛磺酸、甘氨酸、牛磺胆酸和甘氨胆酸的测定

本文采用日立８３５－５０型氨基酸自动分析仪测定比较了广东眼镜蛇蛇胆及牛、猪、兔、鸡胆中牛磺酸、甘氨酸和其他氨基酸的成分与含量,并间接测定了牛磺胆酸与甘氨胆酸的含量和比值。结果表明广东眼镜蛇蛇胆中牛磺酸（６．６６７ｇ／１００ｇ干重）与牛磺胆酸（２７．４７ｇ／１００ｇ干重）的含量最高,而甘氨酸（０．５９８ｇ／１００ｇ干重）与甘氨胆酸（３．７０ｇ／１００ｇ干重）的含量最低,其他氨基酸的含量甚微。实验结果为蛇胆的真伪鉴别及内在质量控制提供了有实用价值的科学依据,同时也提供了一个准确、灵敏、微量的测定方法。     

灵芝孢子粉氨基酸,脂肪酸及元素组成的研究

从灵芝Ｇａｎｏｄｅｒｍａｌｕｃｉｃｈａｍ孢子粉中检出１８种常见氨基酸,总是为７．２９～７．７１ｍｇ／１００ｍｇ;其中甲硫氨酸含量高达３．３０～３．４８ｍｇ／１００ｍｇ人体必需氨基酸含量占总量的６９．４～７０．４％,灵芝孢子粉含有棕榈酸（１９．８％）油酸（５５．２％）,亚油酸（１６．５％）以及少量的肉豆蔻酸,硬脂酸,廿碳烯酸及廿二碳四烯酸等,对５６种元素进行定量或半定量分析,结果表明灵芝孢子粉碳氮比     

双抗体夹心ELISA检测人C蛋白的研究

本文建立了检测人Ｃ蛋白的双抗夹心ＥＬＩＳＡ方法。该方法的最佳实验条件为：－抗浓度５－８．５μｇ／ｍｌ;二抗密度为１：２００－１：１０００倍稀释。制作了Ｃ蛋白浓度与ＯＤ值的关系的工作曲线,指出了用内插法测定Ｃ蛋白的最佳浓度范围为０－１００ｍｇ／ｍｌ之间。     

灵芝菌丝体深层培养及多糖提取工艺研究

灵芝ＳＤ－２２菌株培养条件,培养基组分、ｐＨ、通气量、培养时间等对该菌的生物量和多糖含量均有影响。初步确定了灵芝多糖提取工艺。在优化条件下,生物量为１．８６ｇ／１００ｍｌ培养基,灵芝多糖产量为５１ｍｇ／１００ｍｌ培养基     

Amino acid transport and metabolism in nitrogen-starved cells of Saccharomyces cerevisiae.

Nitrogen-starved yeast derepress a general amino acid permease which transports basic and hydrophobic amino acids. Although both groups of amino acids are metabolized, the derivatives of the basic amino acids are retained by the cells, whereas those of the hydrophobic amino acids are released as acidic and neutral deaminated derivatives. The release of the deaminated derivatives of the hydrophobic amino acids only occurs in the presence of glucose, which presumably produces amino acceptors. The accumulation of intracellular amino acids results in trans-inhibition of the uptake of exogenous amino acids whether the intracellular amino acid is a basic amino acid or the product of intracellular transamination from a hydrophobic amino acid. Variation of permease and transaminase activity was measured during growth under repressed (ammonia-grown) and derepressed (proline-grown) conditions. Maximum levels for both activities occurs at the mid-exponential phase.     

Structure-based statistical analysis of transmembrane helices

Recent advances in determination of the high-resolution structure of membrane proteins now enable analysis of the main features of amino acids in transmembrane (TM) segments in comparison with amino acids in water-soluble helices. In this work, we conducted a large-scale analysis of the prevalent locations of amino acids by using a data set of 170 structures of integral membrane proteins obtained from the MPtopo database and 930 structures of water-soluble helical proteins obtained from the protein data bank. Large hydrophobic amino acids (Leu, Val, Ile, and Phe) plus Gly were clearly prevalent in TM helices whereas polar amino acids (Glu, Lys, Asp, Arg, and Gln) were less frequent in this type of helix. The distribution of amino acids along TM helices was also examined. As expected, hydrophobic and slightly polar amino acids are commonly found in the hydrophobic core of the membrane whereas aromatic (Trp and Tyr), Pro, and the hydrophilic amino acids (Asn, His, and Gln) occur more frequently in the interface regions. Charged amino acids are also statistically prevalent outside the hydrophobic core of the membrane, and whereas acidic amino acids are frequently found at both cytoplasmic and extra-cytoplasmic interfaces, basic amino acids cluster at the cytoplasmic interface. These results strongly support the experimentally demonstrated biased distribution of positively charged amino acids (that is, the so-called the positive-inside rule) with structural data.     

虎纹蛙的含肉率及蛙肉和蛙皮氨基酸组成分析

测定了8只人工养殖虎纹蛙的含肉率及氨基酸组成。结果表明,虎纹蛙的含肉率平均为35．27％;蛙肉和蛙皮干物质中水解氨基酸总量分别为71．740％和79．084％,其中必需氨基酸分别为22．95％和15．88％,分别占氨基酸总量的32．00％和20．08％;游离氨基酸中6种呈味氨基酸含量丰富,分别占游离氨基酸总量的45．50％和60．40％;蛙肉和蛙皮限制氨基酸均为缬氨酸,必需氨基酸指数分别为43.83和27．66。认为虎纹蛙是一种营养价值和养殖价值都较高的品种。     

蒺藜中氨基酸的含量测定

蒺藜（ＴｒｉｂｕｌｕｓｓＴｅｒｒｅｓｔｒｉｓＬ．）为蒺藜科一年生草本植物。又名刺蒺藜、硬蒺藜,在《本草纲目》中列为上品,广布我国各地。药用部位以蒺藜子为主,根、茎、叶、花亦供药用,主治冠心病,高血压等疾病,并具有明显的止咳、祛痰、平喘作用,实验证明,蒺藜皂甙具有抗心肌缺血、抑制血小板凝聚,促进性腺激素样作用及抗衰老作用［１,２］。印度、保加利亚、苏联等国家对蒺藜中所含生物碱、甾醇、黄酮类化合物做了研究,但国内对其它化学成分的研究未见报道。本文对蒺藜叶、子、仁的游离氨基酸和水解氨基酸进行了分析测定。     

人乳中氨基酸的含量及分析方法研究进展

人乳中含有丰富的氨基酸,其中赖氨酸、苏氨酸、亮氨酸、缬氨酸、异亮氨酸、苯丙氨酸、甲硫氨酸和组氨酸等必需氨基酸构成比例合理,牛磺酸和谷氨酸等条件必需氨基酸含量丰富,丙氨酸、丝氨酸、天冬氨酸和甘氨酸等非必需氨基酸含量也较为丰富;人乳中含有的氨基酸在维持婴儿生长发育、增强免疫力、肠道保护等方面发挥重要作用.本文综述了人乳中主要氨基酸的含量及分析方法,以期为婴儿食品的开发及母乳成分数据库的建立提供一定的依据.     

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。     

Utilization of 15N-labelled yeast hydrolysate in Lactococcus lactis IL1403 culture indicates co-consumption of peptide-bound and free amino acids with simultaneous efflux of free amino acids

Lactococcus lactis subsp. lactis IL1403 was grown in medium containing unlabelled free amino acids and ¹⁵N-labelled yeast hydrolysate to gain insight into the role of peptides as a source of amino acids under conditions where free amino acids are abundant. A mathematical model was composed to estimate the fluxes of free and peptide-derived amino acids into and out of the intracellular amino acid pool. We observed co-consumption of peptides and free amino acids and a considerable efflux of most free amino acids during growth. We did not observe significant differences between the peptide consumption patterns of essential and non-essential amino acids, which suggests that the incorporation of a particular amino acid is more dependent on its availability in a readily assimilated form than the organism’s auxotrophy for it. For most amino acids the contribution of peptide-bound forms to the formation of biomass was initially between 30 and 60 % with the remainder originating from free amino acids. During the later stages of fermentation we observed a decrease in the utilization of peptide-bound amino acids, thus indicating that the more readily assimilated peptides are gradually exhausted from the medium during growth.     

4种野生蔬菜的氨基酸含量及其营养价值评价

野生蔬菜具有独特的口味,丰富的营养,有些还具有防病治病的功能,对人体有良好的保健作用.白子菜[Gynura divaricata (L.) DC.]茎叶有消热、舒筋及止血祛瘀的作用,用于镇咳、风湿性关节痛、骨折、创伤止血,痈肿疮疥等症,在民间还作抗癌草使用[1].红凤菜(Gynura bicolor DC.)茎叶有活血止血,解毒消肿的功效,治痛经,血崩,咳血,创伤出血,溃疡久不收口[2].诸葛菜[Orychophragmus violaceus (L.) Schulz]作为野生蔬菜在江苏、安徽民间有很长的食用历史,测定结果表明,该种含有黄酮类化合物[3].马齿苋(Portulaca oleracea L.)具有清热解毒、消炎、利尿、消肿的功效,民间还用于白发症、糖尿病、心血管疾病的治疗[4],中国卫生部将它列为药食同用的植物.     

Amino Acids Contents of Common Wild Edible Mushrooms in Yunnan Province

Edible mushrooms are well known for their value of nutrition. We analysed the contents of 17 amino acids in 41 species of common wild edible mushrooms in Yunnan Province. The results indicate that the types of amino acids are rich and the contents of amino acids are high. The total amino acids contents of Lyophyllum shimeji, Boletus griseus, Termitomyces bulborhizeus, and T.striatus are rather higher than others.     

Low and high affinity amino acid H+-cotransporters for cellular import of neutral and charged amino acids

Amides and acidic amino acids represent the major long distance transport forms of organic nitrogen. Six amino acid permeases (AAPs) from Arabidopsis mediating transport of a wide spectrum of amino acids were isolated. AAPs are distantly related to plasma membrane amino acid transport systems N and A and to vesicular transporters such as VGAT from mammals. A detailed comparison of the properties by electrophysiology after heterologous expression in Xenopus oocytes shows that, although capable of recognizing and transporting a wide spectrum of amino acids, individual AAPs differ with respect to specificity. Apparent substrate affinities are influenced by structure and net charge and vary by three orders of magnitude. AAPs mediate cotransport of neutral amino acids with one proton. Uncharged forms of acidic and basic amino acids are cotransported with one proton. Since all AAPs are differentially expressed, different tissues may be supplied with a different spectrum of amino acids. AAP3 and AAP5 are the only transporters mediating efficient transport of the basic amino acids. In vivo competition shows that the capability to transport basic amino acids in planta might be overruled by excess amides and acidic amino acids in the apoplasm. With the exception of AAP6, AAPs do not recognize aspartate; only AAP6 has an affinity for aspartate in the physiologically relevant range. This property is due to an overall higher affinity of AAP6 for neutral and acidic amino acids. Thus AAP6 may serve a different role either in cooperating with the lower affinity systems to acquire amino acids in the low concentration range, as a system responsible for aspartate transport or as an uptake system from the xylem. In agreement, a yeast mutant deficient in acidic amino acid uptake at low aspartate concentrations was complemented only by AAP6. Taken together, the AAPs transport neutral, acidic and cationic amino acids, including the major transport forms, i.e. glutamine, asparagine and glutamate. Increasing proton concentrations strongly activate transport of amino acids. Thus the actual apoplasmic concentration of amino acids and the pH will determine what is transported in vivo, i.e. major amino acids such as glutamine, asparagine, and glutamate will be mobilized preferentially.