Effects of electroacupuncture on pressor response to angiotensin-(1-7) by amino acid release in the rostral ventrolateral medulla

Unilateral microinjection of Angiotensin-(1-7)[Ang-(1-7)] into the rostral ventrolateral medulla (RVLM) of anesthetized rats caused an increase in mean arterial pressure (MAP) accompanied by an increased release of excitatory amino acid (EAA) glutamate. In contrast, microinjection of Ang779, a selective antagonist of Ang-(1-7) receptor, into the RVLM caused a decrease in MAP accompanied by a deceased release of EAA glutamate as well as an increased release of inhibitory amino acid (IAA) glycine, taurine and gamma-aminobutyric acid. After electroacupuncture (EA) stimulation at "Zusanli"(St.36) for 20 min, the above effects of Ang-(1-7) or Ang779 attenuated. These results suggest that attenuation of EA on the pressor effect of Ang-(1-7) or the depressor effect of Ang779 may be through regulating the corresponding amino acid neurotransmitter release in the RVLM.     

Stigonemapeptin, an Ahp-containing depsipeptide with elastase inhibitory activity from the bloom-forming freshwater cyanobacterium Stigonema sp

Stigonemapeptin (1), a depsipeptide containing an Ahp (3-amino-6-hydroxy-2-piperidone) residue, was isolated from a bloom sample of the freshwater cyanobacterium Stigonema sp. collected from North Nokomis Lake in the Highland Lake District of northern Wisconsin. The planar structure was determined by 1D and 2D NMR experiments as well as HRESIMS analysis. The absolute configurations of the amino acids were determined using the advanced Marfey's method after acid hydrolysis. Stigonemapeptin (1), characterized by the presence of the Ahp residue, also contained the modified amino acids Abu (2-amino-2-butenoic acid) and N-formylated Pro. Stigonemapeptin (1) showed in vitro elastase and chymotrypsin inhibitory activity, with IC(50) values of 0.26 and 2.93 μM, respectively.     

Taspine: bioactivity-guided isolation and molecular ligand-target insight of a potent acetylcholinesterase inhibitor from Magnolia x soulangiana

A bioactivity-guided approach was taken to identify the acetylcholinesterase (AChE, EC 3.1.1.7) inhibitory agent in a Magnolia x soulangiana extract using a microplate enzyme assay with Ellman's reagent. This permitted the isolation of the alkaloids taspine (1) and (-)-asimilobine (2), which were detected for the first time in this species. Compound 1 showed a significantly higher effect on AChE than the positive control galanthamine and selectively inhibited the enzyme in a long-lasting and concentration-dependent fashion with an IC(50) value of 0.33 +/- 0.07 muM. Extensive molecular docking studies were performed with human and Torpedo californica-AChE employing Gold software to rationalize the binding interaction. The results suggested ligand 1 to bind in an alternative binding orientation when compared to galanthamine. While this is located in close vicinity to the catalytic amino acid triad, the 1-AChE complex was found to be stabilized by (i) sandwich-like pi-stacking interactions between the planar aromatic ligand (1) and the Trp84 and Phe330 of the enzyme, (ii) an esteratic site anchoring with the amino side chain, and (iii) a hydrogen-bonding network.     

Kurstakins: a new class of lipopeptides isolated from Bacillus thuringiensis

A novel class of lipopeptides was isolated from Bacillus thuringiensis kurstaki HD-1. Four compounds (1-4) were separated by high-performance liquid chromatography and their primary structures determined using a combination of chemical reactions and mass spectrometry. The four lipopeptides were found to have the same amino acid sequence, Thr-Gly-Ala-Ser-His-Gln-Gln, but different fatty acids. The fatty acyl chain is linked to the N-terminal amino acid residue via an amide bond. Each lipopeptide has a lactone linkage between the carboxyl terminal amino acid and the hydroxyl group in the side chain of the serine residue. Antifungal activity was demonstrated against Stachybotrys charatum.     

OPA-FMOC在线衍生化法测定氨基酸的含量

目的:建立了测定氨基酸的在线衍生化方法.方法:以邻苯二甲醛( OPA)和9-芴甲基氯甲酸酯为衍生化试剂,对其氨基酸进行在线衍生化色谱分析.色谱柱:Zorbax Eclipse-AAA氨基酸分析柱(4.6 mm ×150 mm,5μm),流动相A为40mmol·L-1 Na2HPO4(用8 mol·L-1氢氧化钠溶液调pH 7.8),流动相B为乙腈-甲醇-水(45:45:10)梯度洗脱,流速2 mL·min -1,检测波长338,262 nm,柱温40℃.结果:氨基酸浓度在一定范围内,此法可以测定27种氨基酸的含量,但不适合清开灵注射液中氨基酸的含量测定.结论:该方法不能对清开灵注射液中氨基酸进行准确定量.     

Neamphamide A, a new HIV-inhibitory depsipeptide from the Papua New Guinea marine sponge Neamphius huxleyi

A new HIV-inhibitory cyclic depsipeptide, neamphamide A (2), was isolated from a Papua New Guinea collection of the marine sponge Neamphius huxleyi. Its structure was established through interpretation of spectroscopic data and by acid hydrolysis, derivatization of the free amino acids, and LC-MS analysis of the derivatives. Neamphamide A (2) contains 11 amino acid residues and an amide-linked 3-hydroxy-2,4,6-trimethylheptanoic acid moiety. The amino acid constituents were identified as L-Leu, L-NMeGln, D-Arg, D- and L-Asn, two residues of D-allo-Thr, L-homoproline, (3S,4R)-3,4-dimethyl-L-glutamine, beta-methoxytyrosine, and 4-amino-7-guanidino-2,3-dihydroxyheptanoic acid. In a cell-based XTT assay, 2 exhibited potent cytoprotective activity against HIV-1 infection with an EC50 of approximately 28 nM.     

JBIR-78 and JBIR-95: phenylacetylated peptides isolated from Kibdelosporangium sp. AK-AA56

The search for metabolites of Kibdelosporangium sp. AK-AA56 resulted in the discovery of novel N-phenylacetylated peptides, JBIR-78 (1) and JBIR-95 (2). Compounds 1 and 2 were established to be N-phenylacetylated heptapeptides by extensive NMR and HRESIMS analyses. The absolute configuration of the standard amino acids including a cysteic acid moiety was determined using Marfey's method on the acid hydrolysates of 1 and 2. The relative and absolute configurations of a nonstandard amino acid, β-hydroxyleucine, were elucidated using the J-based and modified Mosher's methods, respectively. In an antimicrobial test, 1 showed antibacterial activity against Micrococcus luteus.     

多花黄精嫩芽主要营养与功效成分研究

为了揭示多花黄精嫩芽中主要营养与功效成分,采集浙江省杭州市临安区天目山镇横塘村麻泥角弄人工栽培的多花黄精(包括浙江磐安、浙江龙泉、安徽青阳3个种源)展叶前、展叶初期和展叶盛期3个不同时期的嫩芽,测定多糖、蛋白质、氨基酸、总酚等含量。结果表明:多花黄精嫩芽中多糖质量分数为2.34%~12.73%,约占根茎的1/3;蛋白质质量分数达107.75~192.49 mg·g-1,为根茎的5.50倍;总氨基酸质量分数为193.13~248.74 mg·g-1,为根茎的4.16倍,其中人体必需氨基酸占总氨基酸的35.57%~39.44%,接近FAO/WHO提出的理想蛋白质的标准(必需氨基酸占总氨基酸40%左右),味觉氨基酸(TaAA)达到160.12~208.29 mg·g-1,揭示了历代本草"初生苗,味极美"的物质基础;总酚质量分数51.21~58.76 mg·g-1,是根茎的2.96倍;对DPPH自由基清除率均达95%以上,明显优于根茎。因此,多花黄精嫩芽是一种非常优质的野菜与功能食品,具有很好的开发潜力。此外,多花黄精嫩芽中主要营养与功效物质与种源、采收季节等密切相关,加强品种选育、嫩芽培育技术研究,对提高嫩芽质量与产量十分重要。     

Determination of the absolute stereochemistry of cyclosmenospongine

The absolute stereochemistry of the sponge metabolite cyclosmenospongine (1) was determined as 5R, 8S, 9R, 10S by chemical correlation. Substitution of the methoxyl group by an amino group in the cyclic product 3 of acid-catalyzed rearrangement of ilimaquinone (5) afforded cyclosmenospongine 1. Cyclosmenospongine was also obtained by acid-catalyzed cyclization of smenospongine (6).     

利用柱前在线衍生-高效液相色谱法测定培植牛黄及天然牛黄中18种氨基酸的含量

目的:建立1种利用高效液相色谱同时测定培植牛黄药材中18种氨基酸含量的方法。方法:以邻苯二甲醛(OPA)和9-芴甲基氯甲酸酯(FMOC)为柱前衍生化试剂。色谱柱为AJS-02氨基酸分析专用柱C18(150 mm×4.6 mm,3μm);流动相A为磷酸氢二钠-四硼酸钠缓冲液(pH 8.2),流动相B为甲醇-乙腈-水(9∶9∶2),梯度洗脱;流速为1.6 mL·min^-1;柱温为50℃;检测波长为338 nm(一级氨基酸)和262 nm(二级氨基酸)。结果:各个氨基酸在线性浓度范围内,峰面积与内标比值与浓度呈良好的线性关系(除Lys外,r>0.9990),平均回收率为90%~110%。结论:本方法准确、灵敏、简便,适用于培植牛黄药材中门冬氨酸等18种氨基酸的含量测定。     

�յ��Ӷ����Ǻ�ָ��������غ��������Ǻ�ָ��ξ-���ܲ�������ø�������Ӱ��

??OBJECTIVE To explore the effects of methyl jasmonic acid(MeJA), arachidonic acid(AA) and acetylsalicylic acid(ASA) on fucoxanthin production and PtZDS gene expression in Phaeodactylum tricornutum.METHODS The full length cDNA of PtZDS gene in P. tricornutum was obtained by HiSeq^TM Illumina 2000 and bioinformatics analysis. HPLC was used to determine the production of fucoxanthin in Phaeodactylum tricornutum, and RT-PCR was used to determine the expression level of PtZDS.RESULTS The total length of PtZDS gene was 1 905 bp, containing an open reading frame of 1 776 bp encoding 591 amino acids.The deduced amino acid sequence analysis showed that PtZDS protein contained a typical amino oxidase domain, NAD(P)-binding Rossmann-like domain and a chloroplastic transit peptide sequence.The phylogenetic analysis demonstrated that PtZDS was homologous with Thalassiosira pseudonana CCMP1335(76%). Under the treatment of 0.1 mg·L^-1 AA, 25 mg·L^-1 ASA and 100 μmol·L^-1 MeJA, the highest yield of unit cell fucoxanthin content was achieved.Upon the observation of PtZDS regulation expression, the expression level of PtZDS reached a peak value under the treatment of 0.1 mg·L^-1 AA, 50 μmol·L^-1 MeJA and 10 mg·L^-1 ASA.CONCLUSION The expression of PtZDS gene has certain relationship with the fucoxanthin synthesis of P. tricornutum. Under the treatment of 100 μmol·L^-1 MeJA, the ability of synthetic fucoxanthinis the strongest in P. tricornutum.     

肽图分析在重组人甲状旁腺素1-34产品质量控制中的应用

 目的通过肽图谱分析,鉴定重组人甲状旁腺素1-34产品一级结构的完整性和准确性。方法采用胰蛋白酶裂解-反相高效液相色谱法测定肽图;用LC-MS/MS和N端氨基酸测序鉴定产品氨基酸序列。结果建立重组人甲状旁腺素1-34产品肽图测定法,并鉴定出肽图异常产品的氨基酸序列。结论肽图分析能有效地控制重组人甲状旁腺素1-34产品一级结构的完整性和准确性,对该产品的质量控制具有重要意义。     

桂蚕沙的氨基酸组分和金属元素及有害元素分析

目的:测定桂蚕沙中的氨基酸组分、金属元素及有害元素的含量,并对其营养价值及安全性进行评价.方法:采用氨基酸自动分析仪测定氨基酸组分;采用火焰原子吸收法测定Cu,Fe,Mn,Zn,K,Na,Mg,Ca;石墨炉原子吸收法测定Pb,As,Cd.结果:测得桂蚕沙中含有16种氨基酸,总含量为7.95％,其中谷氨酸含量最高,占总氨基酸的12.45％.测得Fe,Mn,Zn等10种金属元素,其中Ca的含量高达34000 μg·g-1,重金属的含量为Cu 8.2 μg·g-1,Pb 3.1 μg·g-1,Cd 0.088 μg·g-1,As0.28 μg·g-1.结论:桂蚕沙含有较丰富的氨基酸组分和金属元素,其重金属及有害元素的含量均在安全范围内,是一种安全有效且营养价值丰富的保健及药用原料.     

柱前衍生-HPLC法对水蛭的指纹图谱及其16种氨基酸含量测定研究

目的建立18批水蛭药材游离类氨基酸柱前衍生-高效液相色谱(HPLC)指纹图谱的分析方法,并完成对水蛭中16种游离和水解氨基酸成分的同时定量。方法加水超声提取游离氨基酸,以6 mol/L盐酸提取水解氨基酸;基于异硫氰酸苯酯(PITC)柱前衍生法,以氨基酸分析专用色谱柱(4.6×250 mm,5μm);流动相A为0.1 mol/L无水乙酸钠(pH 6.5)-乙腈(93∶7),B为乙腈-水(4∶1);流速0.8 mL/min,检测波长254 nm,柱温40℃进行梯度洗脱。采用“中药色谱指纹图谱相似度评价系统(2012 A版)”、SAS和SIMCA-13.0进行药材的相似度评价和聚类分析。结果建立了18批水蛭药材中游离氨基酸HPLC指纹图谱的共有模式,确定25个共有峰,并指认16种氨基酸成分;18批药材相似度均高于0.960;聚类分析与主成分分析结果一致,均将药材分为3类;含量测定结果表明不同批次的药材中氨基酸含量差异较大,水解氨基酸中含量最高的谷氨酸范围为7.26~18.36 mg/g,游离氨基酸含量最高的丙氨酸范围为1.43~4.39mg/g。结论建立了18批水蛭药材中游离类氨基酸的HPLC指纹图谱,同时测定了18批水蛭药材中游离和水解氨基酸的含量,该方法准确,重复性好,可全面反映水蛭药材的氨基酸信息,为该药材的质量控制提供一定的参考依据。     

Chrysosporide, a cyclic pentapeptide from a New Zealand sample of the fungus Sepedonium chrysospermum

A new cyclic pentapeptide, chrysosporide (1), was isolated from a New Zealand sample of the mycoparasitic fungus Sepedonium chrysospermum by bioactivity-guided fractionation. The planar structure was deduced by detailed spectroscopic analysis, and the absolute configurations of the amino acid residues were defined by Marfey's method. As both enantiomers of Leu occurred in chrysosporide, molecular mechanics calculations were applied to the analysis to distinguish between the possible structural isomers. Only the lowest energy conformers of the cyclo-(L-Val-D-Ala-L-Leu-L-Leu-D-Leu) isomer were in agreement with the observed NOEs, suggesting that this was the most probable amino acid sequence for chrysosporide (1).     

红花黄酮醇合酶基因的全长cDNA克隆及植物表达载体的构建

黄酮醇合酶(flavonol synthase,FLS)是黄酮化合物代谢途径中的关键酶之一。本文在红花转录组测序结果中获得中间序列的基础上,采用RT-PCR和RACE技术,从我国传统中药材红花花瓣中克隆到黄酮醇合酶基因的全长c DNA。该基因全长1 201 bp,开放阅读框1 011 bp,编码336个氨基酸。系统进化分析表明,红花FLS基因编码氨基酸与同属菊科植物氨基酸具有一定的同源性,其中与金光菊的亲缘关系最近。通过分子生物学方法,成功构建p BASTA-FLS植物表达载体。为后续研究该基因的生物功能及黄酮化合物合成机制奠定了基础。     

Psychrophilin A and cycloaspeptide D, novel cyclic peptides from the psychrotolerant fungus Penicillium ribeum

Two fungal metabolites, psychrophilin A (1) and cycloaspeptide D (2), together with the known cycloaspeptide A (3) were isolated from the psychrotolerant fungus Penicillium ribeum using high-speed countercurrent chromatography (HSCCC) and preparative HPLC. The structures were determined from 1D and 2D NMR techniques, HREIMS, tandem mass spectrometry (ESMS/MS), and X-ray crystallography. The amino acid residues of psychrophilin A (1) and cycloaspeptide D (2) were all found to possess the l configuration by Marfey's method. Psychrophilin A (1) is the first natural cyclic peptide containing a nitro group instead of an amino group.     

Theopapuamide, a cyclic depsipeptide from a Papua New Guinea lithistid sponge Theonella swinhoei

Theopapuamide (1), a new cytotoxic peptide, has been isolated from the lithistid sponge Theonella swinhoei from Papua New Guinea. The structure was established by analysis of NMR, mass spectrometry, and chemical methods. The undecapeptide (1) contains several unusual amino acid residues, of which the occurrence of beta-methoxyasparagine and 4-amino-5-methyl-2,3,5-trihydroxyhexanoic acid (Amtha) is unprecedented in natural peptides. Compound 1 also contains an amide-linked fatty acid moiety, 3-hydroxy-2,4,6-trimethyloctanoic acid (Htoa). Theopapuamide (1) was cytotoxic against CEM-TART and HCT-116 cell lines, with EC50 values of 0.5 and 0.9 microM, respectively.     

Serinocyclins A and B, cyclic heptapeptides from Metarhizium anisopliae

Two new cyclic heptapeptides, serinocyclins A (1) and B (2), were isolated from conidia of the entomopathogenic fungus Metarhizium anisopliae. Structures were elucidated by a combination of mass spectrometric, NMR, and X-ray diffraction techniques. Serinocyclin A (1) contains three serine units, a hydroxyproline (Hyp), a beta-alanine (beta-Ala), and two uncommon nonproteinogenic amino acids, 1-aminocyclopropane-1-carboxylic acid (Acc) and gamma-hydroxylysine (HyLys). The peptide sequence established for 1 by NMR is cyclo-(Acc-Hyp-Ser1-HyLys-beta-Ala-Ser2-Ser3). Serinocyclin B (2) has Lys in place of the HyLys unit found in 1. Chiral amino acid analysis indicated the presence in both compounds of one (2 S,4 R)-Hyp, two L-Ser, and one D-Ser residue. A Lys found in the hydrolyzate of 2 was established as D-configured. A crystal structure of 1 established the position of the D-Ser (Ser2) and the absolute configuration of the HyLys unit (2 R,4 S). The absence of methyl groups is unusual among fungal peptides and, along with the charged lysyl side chain and multiple hydroxyl groups, contributes to the polar nature of the compounds. Serinocyclin A produced a sublethal locomotory defect in mosquito larvae at an EC 50 of 59 ppm.     

Mechanism of the Reversal Effect of Acupuncture on the Fall of Blood Pressure Induced by Angiotensin-(1-7) in the Caudal Ventrolateral Medulla of Rats

目的:研究电针逆转血管紧张素-(1-7)[Ang-(1-7)]在大鼠延髓尾端腹外侧区(CVLM)引起血压降低的作用机制.方法:采用中枢核团微量注射和微透析,以及高效液相色谱(HPLC)荧光检测等技术观察Ang-(1-7)及其选择性受体拮抗剂(D-Ala7)-Ang-(1-7)(Ang-779)在大鼠CVLM引起血压改变时氨基酸类神经递质释放的变化以及电针对血压和氨基酸类递质释放的影响.结果: 在CVLM微量注射Ang-(1-7)可引起血压降低,同时伴该区内兴奋性氨基酸谷氨酸(Glu)释放增多和抑制性氨基酸牛磺酸(Tau)释放减少;相反,在CVLM微量注射Ang-779则可引起血压升高,同时伴Glu释放减少和Tau释放增多.在相当于人"足三里"穴位电针20 min,可分别抑制在CVLM微量注射Ang-(1-7)或Ang-779所引起的血压降低或升高,同时也能部分抵消注射Ang-(1-7)或Ang-779所引起的Glu、Tau释放的改变.结论:电针逆转Ang-(1-7)或Ang-779在CVLM引起的降压或升压作用可能与Glu、Tau释放量的改变有关.