Identification and Distribution of m- and p-Hydroxyphenylacetic Acids in the Brain of the Rat

The m and p isomers of hydroxyphenylacetic acid have been identified and quantitated in whole rat brain and in several regions using a capillary column high resolution gas chromatography–mass spectrometry procedure. Their concentrations were: for m-hydroxyphenylacetic acid (mean ± S.E., number of determinations in parentheses)—whole brain, 2.3 ± 0.3 ng/g (7); hypothalamus, 1.2 ± 0.3 ng/g (5); caudate nucleus, 5.5 ± 0.6 ng/g (5); brain stem, 1.8 ± 0.1 ngig (5); cerebellum, 1.2 ± 0.1 ng/g (5) and the “rest,” 1.7 ± 0.1 ng/g (5); and for p-hydroxyphenylacetic acid–whole brain, 10.6 ± 0.7 ng/g (7); hypothalamus, 4.5 ± 0.1 ng/g (4); caudate nucleus, 28.3 ±1.6 ng/g (5); brain stem, 8.6 ± 0.6 ng/g (5); cerebellum, 8.1 ± 0.4 ng/g (9, and the “rest,” 5.3 ± 0.5 ng/g (5). This heterogeneous distribution parallels closely that exhibited by their respective precursor amines, m- and p-tyramine.     

Purification and characterization of the 4-hydroxyphenylacetic acid-3-hydroxylase from Pseudomonas putida U

4-Hydroxyphenylacetic acid-3-hydroxylase from Pseudomonas putida U was purified to homogeneity (96-fold) from bacterial cultures grown in a chemically defined medium containing 4-hydroxyphenylacetic acid as the sole carbon source. The maximal rate of catalysis occurred at pH 7.5 and 40°C. Under these conditions, the K_m values calculated for 4-hydroxyphenylacetic acid, NADH and FAD were 38, 41 and 4 μM respectively. The native enzyme (M_r 65 000) had two identical subunits in an α₂ oligomeric structure and required the addition of FAD, so it was classified as an external flavoprotein monooxygenase. 4-Hydroxyphenylacetic acid-3-hydroxylase showed a broad substrate range. It was specifically induced by 4-hydroxyphenylacetic acid, although phenylacetic acid and some phenyl-alkanoic acids also induced enzymatic activity to a lesser extent. 4-Hydroxyphenylacetic acid-3-hydroxylase induction and 4-hydroxyphenylacetic acid consumption were unaffected by the presence of glucose, suggesting that the uptake and hydroxylation of 4-hydroxyphenylacetic acid are not under carbon catabolite repression.     

Plasma concentrations of p- and m-hydroxyphenylacetic acid and phenylacetic acid in humans : Gas chromatographic—high-resolution mass spectrometric analysis

Conjugated and unconjugated phenylacetic acid and m- and p-hydroxyphenylacetic acid have been determined in the plasma of normal, healthy subjects after fasting, consumption of a meal and ingestion of deuterium-labelled amine precursors, by high-resolution gas chromatography—high-resolution mass spectrometry with selected ion monitoring of their trifluoroethyl-pentafluoropropionyl derivatives.We observed that all three conjugated acids are higher in fasting than in non-fasting subjects, and unconjugated phenylacetic acid was lower. Ingestion of deuterium-labelled amine precursors resulted in the appearance in the blood of the correspondingly labelled acids, a peak in the concentrations being reached about 1 h after consumption. Conjugated and unconjugated acids as expected increased following the consumption of a meal.Unconjugated phenylacetic acid was significantly higher in females than in males. Most values tended to increase with age, with male unconjugated and conjugated m-hydroxyphenylacetic acid and female conjugated phenylacetic and m-hydroxyphenylacetic acids increasing significantly.     

Degradation of homovanillate by a strain of Variovorax paradoxus via ring hydroxylation

Abstract A newly isolated strain of Variovorax paradoxus could grow on homovanillate and several monohydroxylated phenylacetic acids. During growth on homovanillate, the organism formed separate NAD(P)H-dependent hydroxylases with activity towards 4-hydroxyphenylacetic acid and homovanillate. Homovanillate hydroxylase catalysed a typical monooxygenase reaction and had little activity towards 4-hydroxyphenylacetic acid. GC-MS and TLC analysis suggested that homovanillate was 1-hydroxylated to yield a dihydroxymonomethoxyphenylacetic acid which served as a substrate for homogentisate 1,2-dioxygenase. Methanol, but not formaldehyde, was released either during ring-cleavage or subsequent metabolism of the ring-cleavage product.     

两步法培养对丰富栅藻脂肪酸和氨基酸的影响

为了提高丰富栅藻的油脂产量和评估培养条件对其营养成分的影响,对丰富栅藻的培养基正交优化后,对其进行两步法培养并分析培养前后的脂肪酸和氨基酸的变化。结果表明：两步法培养后丰富栅藻的生物量、油脂含量和油脂产量分别达到23.57 g/L、33.49%和7.58 g/L; 丰富栅藻的单不饱和脂肪酸（MUFAs）特别是C18：1（n-9）的相对含量有所上升,但是饱和脂肪酸（SFAs）和多不饱和脂肪酸（PUFAs）的相对含量有所下降; 氨基酸特别是必需氨基酸的总量降低; 但丝氨酸和蛋氨酸的含量却略有增加。     

Effects of salmon calcitonin and anti-salmon calcitonin antibody on plasma calcium concentrations in the goldfish,Carassius auratus

The role of calcitonin (CT) in plasma calcium regulation was studied by the administration of exogenous CT and anti-salmon(s) CT antibody using goldfish,Carasius auratus, loaded or otherwise with calcium. CT elicited a decrease in plasma calcium concentrations at a dose of 10 ng/g body weight 1 h after administration. However, no effects were observed following doses of 30 ng and 50 ng/g 1 h, nor for the three doses 3 h after administration. In calcium-loaded fish, the effect of CT was different depending on the dosage of CT. Ten ng and 50 ng/g induced a decrease and an increase in plasma calcium concentrations, respectively, 3 h after administration. Anti-sCT antibody (0.02 μg or 0.1 μg/g) did not affect plasma calcium concentrations. In calcium-loaded fish, neither dose of anti-sCT antibody changed plasma calcium concentrations 1 h after administration. However, following a dose of 0.1 μg/g, plasma calcium concentrations decreased after 3 h. A positive correlation between plasma calcium concentrations and the gonad somatic index (GSI) in females was no longer apparent after administration of anti-sCT antibody. There was no relationship between plasma calcium concentrations and GSI in control and anti-sCT antibody-treated males. These results suggested that CT regulates plasma calcium concentrations in different ways depending on the dosage with CT having a role in calcium physiology during vitellogenesis.     

TOFA对人食管鳞癌Eca109和KYSE-450细胞生长的影响*

目的: 探讨5-十四烷氧基-2-呋喃酸(TOFA)对人食管鳞癌(ESCC)细胞Eca109和KYSE-450细胞增殖、周期和凋亡的影响。方法: 将Eca-109细胞和KYSE-450细胞分为对照组(DMSO)和实验组(TOFA),细胞(4×10³ cells/100 μl)接种于96孔板中,每个浓度设置5个复孔,培养24 h后,给予DMSO(对照)和不同浓度(1、3、5、10 μg/ml)TOFA处理,继续培养24、48和72 h;MTT检测细胞增殖,流式细胞术检测细胞周期和凋亡,Western blot检测p21、Cleaved caspase-3表达水平及p-AKT、p-mTOR、p-4EBP1修饰水平,专用试剂盒检测细胞内游离脂肪酸。结果: 与DMSO组比较,TOFA以浓度和时间依赖性方式抑制Eca109和KYSE-450细胞增殖(P均<0.05),处理48 h的IC₅₀分别为4.65和3.93 μg / ml;实验组细胞G2 / M 期细胞百分比增加,细胞凋亡率增高,p21、Cleaved caspase-3蛋白表达水平上调(P均<0.05),p-AKT、p-mTOR、p-4EBP1修饰水平下调(P均<0.05)。结论: TOFA抑制人食管鳞癌细胞增殖、阻滞细胞周期并促进细胞凋亡,其机制可能与其抑制AKT/mTOR/4EBP1信号通路有关。     

15-HETE is the main eicosanoid present in mucus of ulcerative proctocolitis.

Prostaglandins, leukotrienes and mono-hydroxy acid products of arachidonic acid were measured in mucus of freshly recovered morning stools of a patient with an exacerbation of ulcerative proctocolitis. Eicosanoids in ether extracts were separated by high performance liquid chromatography and amounts determined by radioimmunoassay. Four hydroxy-eicosatetraenoic acids were detected, of which the most important one was identified as 15-hydroxy eicosatetraenoic acid (530 ng/g mucus). Leukotriene B4 was also present (21 ng/g mucus) and small amounts of immunoreactive leukotriene C4 (less than 0.8 ng/g mucus). The prostaglandins 6-keto-PGF1 alpha and PGE2 and thromboxane B2 were found in amounts of 3.7, 2.0 and 9.2 ng/g mucus, respectively.     

Purification and biochemical characterization of phenylacetyl-CoA ligase from Pseudomonas putida. A specific enzyme for the catabolism of phenylacetic acid

A new enzyme, phenylacetyl-CoA ligase (AMP-forming) (PA-CoA ligase, EC 6.2.1-) involved in the catabolism of phenylacetic acid (PAA) in Pseudomonas putida is described and characterized. PA-CoA ligase was specifically induced by PAA when P. putida was grown in a chemically defined medium in which phenylacetic acid was the sole carbon source. Hydroxyl, methyl-phenylacetyl derivatives, and other PAA close structural molecules did not induce the synthesis of this enzyme and neither did acetic, butyric, succinic, nor fatty acids (greater than C5 atoms carbon length). PA-CoA ligase requires ATP, CoA, PAA, and MgCl2 for its activity. The maximal rate of catalysis was achieved in 50 mM HCl/Tris buffer, pH 8.2, at 30 degrees C and under these conditions, the Km calculated for ATP, CoA, and PAA were 9.7, 1.0, and 16.5 mM, respectively. The enzyme is inhibited by some divalent cations (Cu2+, Zn2+, and Hg2+) and by the sulfhydryl reagents N-ethylmaleimide, 5,5'-dithiobis(2-nitrobenzoic acid), and p-chloromercuribenzoate. PA-CoA ligase was purified to homogeneity (513-fold). It runs as a single polypeptide in 12% sodium dodecyl sulfate-polyacrylamide gel electrophoresis and has a molecular mass of 48 +/- 1 kDa. PA-CoA ligase does not use as substrate either 3-hydroxyphenylacetic, 4-hydroxyphenylacetic, or 3,4-dihydroxyphenylacetic acids and shows a substrate specificity different from other acyl-CoA-activating enzymes. The enzyme is detected in P. putida from the early logarithmic phase of growth and is repressed by glucose, suggesting that PA-CoA ligase is a specific enzyme involved in the utilization of PAA as energy source.     

不同类型特种稻种质营养及功能性成分含量的差异

本研究以具有有色种皮、巨胚、甜味、香味、糯性等单一特殊性状或2个以上特殊性状聚合于一体的新创制特种稻种质39份和1份白米种质(对照)为试验材料,进行了黑米、黑褐米、红米、香糯米、黑巨胚糯米、红巨胚糯米、巨胚糯米、黑甜米、红甜米、白甜米等不同类型特种稻种质的营养及功能性成分含量的差异评价。结果表明,供试特种稻类型在大部分氨基酸含量和矿质元素含量上与白米差异不显著,只在个别氨基酸和矿质元素含量上与白米呈显著或极显著差异。黑褐米、红米、黑巨胚糯米、红巨胚糯米、巨胚糯米、红甜米和白甜米等7种类型的赖氨酸含量显著或极显著高于白米,高2.91%~24.68%;黑米、黑褐米、红米、香糯米、黑巨胚糯米和红甜米等6种类型的铁含量显著或极显著高于白米,高17.62%~68.09%;黑褐米、红米、黑巨胚糯米、红巨胚糯米、黑甜米、红甜米、白甜米等7种类型的钙含量显著或极显著高于白米,高23.56%~49.46%;黑米、黑褐米、红米、黑甜米、红甜米、白甜米等6种类型的锌含量显著或极显著高于白米,高12.21%~55.87%。由此表明,具有有色种皮、巨胚、甜味、香味、糯性等单一特殊性状或2~3个特殊性状的聚合对赖氨酸含量与铁、钙和锌含量的提高方面具有一定的增加效应,认为在今后以赖氨酸、铁、钙和锌含量为目标性状的功能性水稻育种中,多个特殊性状的聚合将是增加上述功能性成分含量的有效途径之一。通过鉴定评价,从创新种质中还筛选出一些功能性成分含量相对较高的优异种质,白甜米1553和红巨胚糯米1476的赖氨酸含量较高,比白米分别高29.37%和23.42%;红米1439和红米1440的铁含量较高,比白米分别高99.05%和80.00%;黑甜米1511和黑甜米1515的硒含量较高,比白米分别高194.14%和136.48%;白甜米1551和香糯米1446的γ-氨基丁酸含量较高,比白米分别高14.56%和11.83%;黑巨胚糯米1464和黑米1432的花色苷含量较高,比供试18份有色稻米的平均值分别高253.23%和248.83%。这些新创制的功能性成分含量较高的水稻种质有待于今后在育种、生态适应性鉴定与产业化中进一步得到利用。     

Amino acids in cat fallopian tube and follicular fluids

Aminograms of tubal and follicular fluids were obtained using fluids collected by aspiratory puncture from six cats. The amino acids were separated and quantified by high-performance liquid chromatography analysis. The serum of the cats was used as control. The three most prevalent amino acids quantified in cat tubal fluid were glycine, glutamic acid, and taurine. Their mean concentrations were 840 μmol/l (μm), 808 μm and 596 μm, respectively. The three most prevalent amino acids quantified in cat follicular fluid were alanine, glutamine, and taurine. Their mean concentrations were 359 μm, 351 μm, and 258 μm, respectively. This result is consistent with aminograms of tubal fluid previously determined in other mammals. As previously observed in other species and humans, glycine was quantitatively the most abundant and most prevalent free amino acid in cat tubal fluid. The total quantity of amino acids in tubal fluid was similar in cats and other species. However, in contrast with other species studied, hypotaurine was not detected in tubal and follicular fluids of female cats.     

Free amino acid composition in juveniles of Mytilus galloprovincialis: spatial variability after Prestige oil spill

Composition of free amino acids (FAA) in juveniles of Mytilus galloprovincialis was analysed along a large geographical coastline area in Galicia (NW Spain). Individuals were sampled in February 2003, three months after the Prestige oil spill. Pollution values at sampling time were reported as polycyclic aromatic hydrocarbons (PAHs) concentrations in soft tissues of individuals and varied between the highest amount observed in Carrumeiro mussels (502 ng/g dw) and the lowest in Pindo mussels (196 ng/g dw), both locations being close to each other in the centre of the geographical area under study. Pollution values in the other populations varied within the range of 241-347 ng/g dw. Total free amino acids (TFAA) were highest in Agui?o-Pindo-Carrumeiro juveniles at the centre of the Coastline area studied (420-462 micromol/g dw) as compared to the other populations at North and South of Galicia (312-347 micromol/g dw). TFAA results were based on the variability observed in protein free amino acids (PFAA micromol/g dw) among populations (214-249 micromol/g dw for Agui?o-Pindo-Carrumeiro mussels and 98-149 micromol/g dw for the other populations) whereas non-protein free amino acids (NPFAA) taurine and ornithine did not show any significant spatial pattern of variation. Glycine and alanine represented the most abundant PFAA (16-29% and 2.7-11.9% of TPFAA, respectively) and significant correlations between PFAA and both the protein content of soft tissues (r=-0.82) and the condition index of juveniles (r=0.86) were observed. No significant relationships were detected, however, between pollution values in soft tissues as PAHs and FAA profiles with the exception of alanine concentrations as percentage of TFAA (r=0.88; P<0.01). The latter seemed to be an "all or nothing" effect likely due to the influence of other abiotic factors at one of the sampling sites. Such relationship was found not significant when the outlier represented by Carrumeiro mussels was removed from the analysis. The most abundant free amino acid taurine (43.2-68.5%TFAA) followed an inverse variability of that of glycine and by extension of the group PFAA most likely as a compensatory decrease in mussel populations with low protein content (and high condition index). Accordingly, taurine:glycine (t:g) ratio varied between 1 and 2 in most mussel populations but increased up to 3.2-4.2 in Miranda and Bueu mussels at both ends of the geographical interval studied with a corresponding PAHs concentrations of 261 and 304 ng/g dw, respectively. These mussel populations with the highest t:g ratios were characterised by the lowest PFAA contents (below 40%) and condition index values (below 10%). Results of the present study established a significant link between energetic status of growing juveniles and FAA concentrations in environments with different pollution degrees. Variability of the free amino acids profiles in soft tissues were related to endogenous factors of juveniles (protein content, condition index) whereas no relationship with contamination values could be observed. The utility of t:g ratio as general condition factor for M. galloprovincialis is also corroborated for in situ growing juveniles.     

Central antinociceptive effects of lysine-vasopressin and an analogue

Vasopressin (VP) neurons project to extrahypothalamic sites involved in pain perception, including the substantia gelatinosa of the spinal cord as well as the trigeminal and vagus nerves. Previous studies have reported antinociceptive activity following intracerebroventricular (ICV) or subcutaneous (SC) VP injections (16–100 μg) on the tail-flick test while hyperalgesia has been observed in rats either genetically deficient in VP or treated with antisera to VP. The present study investigated whether nanogram (ng) doses of lysine-vasopressin (LVP) and a VP analogue with prolonged activity increased tail-flick latencies and flinch-jump thresholds following ICV or SC injections. LVP (150 and 500 ng, ICV) significantly increased tail-flick latencies while the analogue 1-deamino-(8-Lys-N^?-(Gly-Gly-Gly))-VP (500 ng, ICV) produced more powerful and prolonged analgesia. In contrast, latencies were not increased by SC injections of LVP (150–1500 ng). Further, flinch-jump thresholds were affected minimally by either ICV or SC LVP injections. These data suggest a role for VP in pain modulation and a central site of this action.     

Nutritional requirements for the production of dithiolopyrrolone antibiotics by Saccharothrix algeriensis NRRL B-24137

The amino acid and humic acid requirements of Saccharothrix algeriensis NRRL B-24137 for growth and production of the dithiolopyrrolone antibiotics were studied in a semi-synthetic medium (SSM). Nature and concentration of amino acids and humic acid strongly influenced the growth and dithiolopyrrolone specific production.

The highest value of thiolutin (acetyl-pyrrothine) specific production was obtained in the presence of 1 g/l humic acid (336 mg/g DCW), and in the presence of 5 mM l-cystine (309 mg/g DCW) as compared to 19 mg/g DCW obtained with the control. Furthermore, thiolutin production was increased about six-fold, four-fold and three-fold in the presence of l-proline, l-glutamic acid and dl-histidine, respectively. In contrast, the production of thiolutin was reduced by addition of other amino acids such as l-glutamine, dl-ethionine, l-methionine and l-arginine. The highest value of isobutyryl-pyrrothine production was obtained in the presence of 2,6-diaminopimelic acid and l-lysine (7.8 and 1.0 mg/g DCW, respectively). However, the highest value of butanoyl-pyrrothine production was obtained in the presence of humic acid (6.6 mg/g DCW), followed by l-cysteine and l-proline (3.6 and 3.2 mg/g DCW, respectively). In addition, the maximum specific production of senecioyl-pyrrothine (29 mg/g DCW) and tigloyl-pyrrothine (21 mg/g DCW) was obtained in the presence of humic acid. We found that, except for isobutyryl-pyrrothine, production of all dithiolopyrrolones was favoured by addition of l-proline. The maximum specific production was obtained with l-proline at concentrations of 2.50 mM for thiolutin (133 mg/g DCW), 1.25 mM for senecioyl-pyrrothine, tigloyl-pyrrothine and butanoyl-pyrrothine production (29, 23 and 3.9 mg/g DCW, respectively). Production of all dithiolopyrrolones strongly decreased as the l-methionine or dl-ethionine concentration was increased in the culture medium.     

CORRELATIONS BETWEEN A FLUORIMETRIC and MASS FRAGMENTOGRAPHIC METHOD FOR THE DETERMINATION OF 3-METHOXY-4- HYDROXYPHENYLACETIC ACID and TWO MASS FRAGMENTOGRAPHIC METHODS FOR THE DETERMINATION OF 3-METHOXY-4- HYDROXYPHENYLETHYLENE GLYCOL IN CEREBROSPINAL FLUID

One-hundred and twenty-two lumbar cerebrospinal fluid (CSF) samples were assayed for 3-methoxy-4-hydroxyphenylacetic acid (HVA) by both a fluorimetric and mass fragmentographic method. The correlation coefficient (cc) and residual standard deviation (Syx) of the results were calculated as 0.966 and 23.3 ng/ml, respectively. If only samples containing less than 100ng/ml of HVA were considered, somewhat different values for cc and Syx were found (0.854 and 10.0 ng/ml, respectively). The data obtained by the fluorimetric method were consistently 17% lower than those obtained by the mass fragmentographic method. Spiking experiments resulted in 96.5 ± 7.8% recovery for the fluorimetric method, whereas the use of a deuterated internal standard was found to compensate completely for losses in the mass fragmentographic method. In addition the correlation between two different mass fragmentographic methods for the simultaneous determination of HVA and 3-methoxy-4-hyd-roxyphenylethylene glycol (MOPEG) in CSF was studied. The measurements were performed in different laboratories and resulted in correlation coefficients of 0.941 and 0.940 and residual standard deviations of 7.6 and 1.0 ng/ml for HVA and MOPEG, respectively. From all data we conclude that mass fragmentographic methods for the determination of catecholamine metabolites in CSF are superior to fluorimetric methods because of their selectivity, reproducibility and accuracy.     

Determination of Trace Phthalic Acid Monoesters in Sediments and Soils by GC-MS

A simple procedure for determining trace phthalic acid monoesters (PAMs) in sediments/soils was developed. The method used ultrasonic extraction, silylation derivatization, and GC-MS. After ultrasonic extraction, the supernatants were reextracted with dichloromethane, silylated, and did not require further clean-up before GC-MS analysis. Effects of parameters, such as extraction solvents, pH of water as extraction solvent and sediment/soil properties, on the recovery of PAMs were studied. Five sediments from Tianjin city and one red soil from Jiangxi province were used. The results showed that organic carbon (OC) content played an important role in the recovery of PAMs. The optimal extraction solvent for sediments/soils with >1% of OC content and high CEC was 0.01 M HCl aqueous solution and pure water was better for sediments/soils with <1% of OC content. In 5 g sediment/soil sample (dry weight), the method detection limit (MDL) was below 0.04 ng/g for mono-n-butyl phthalate (MBP) and 0.02 ng/g for mono-(2-ethylhexyl)-phthalate (MEHP). Average recoveries of MBP and MEHP were 81.6%?105.2% and 76.0%?95.6%, respectively, with relative standard deviations ≤ 6.6%. MBP and MEHP in the sediment and soil samples studied were detected at levels of 9.2–57.1 and 13.0–166.7 ng/g, respectively.     

Perfluorinated Compounds Distribution and Source Identification in Sediments of Lake Victoria Gulf Basin

Perfluorooctanoic acid and perfluorooctane sulfonate were determined in the sediments from Winam Gulf, which is in the Kenyan side of Lake Victoria and in its source rivers. The sources of perfluorinated compounds within the Gulf of Lake Victoria have been identified and their levels determined for the first time, in this study, using SPE and HPLC-MS-MS analytical methodology. Variability in the concentrations of perfluorooctanoic acid and perfluorooctane sulfonate ranged from 1.4–99.1 and <1–57.5 ng/g in river sediments, respectively, which was higher than concentrations obtained from lake sediments (range perfluorooctanoic acid <1–24.1 ng/g and perfluorooctane sulfonate <1–4.0 ng/g). The results obtained suggested generalized point sources such as domestic and industrial waste indicated by significant correlation and regression of r² = 0.857. Sampling sites within and near sewage and water treatment facilities gave the highest concentrations of both analytes, and were observed to be the main source of perfluorinated compounds pollution. The lowest limit of quantification was 1 ng/g for both analytes and limits of detection were 0.1 and 0.2 ng/g for perfluorooctanoic acid and perfluorooctane sulfonate, respectively. Typical values for recovery obtained were higher than 78% from spiked amounts ranging from 1 to 150 ng. Quantifying perfluoro alkylated compounds in sediments have provided insights into their source, distribution, and mobility in the Lake Victoria Basin.     

顺式藁苯内酯口服给药在大鼠血浆和脑内的药动学特性(英文)

建立大鼠血浆和脑中Z-槀苯内酯(LIG)浓度测定的高效液相色谱法。采用Agilent Hypersil ODS C18色谱柱(150mm×4.6mm,5μm),流动相为甲醇-5%异丙醇水溶液(60:40,v/v),流速为1.0mL/min,检测波长为280nm。血浆与脑中槀苯内酯浓度线性检测范围分别为93.75~3750ng/m(r=0.9999)和93.75~3750ng/g(r=0.9997),日内及日间精密度RSD10%。本法适用于大鼠口服LIG后血浆及脑中药物浓度的研究。     

Influence of pumpkin seed cake and extruded linseed on milk production and milk fatty acid profile in Alpine goats

The aim was to determine the effect of substituting pumpkin seed cake (PSC) or extruded linseed (ELS) for soya bean meal in goats’ diets on milk yield, milk composition and fatty acids profile of milk fat. In total, 28 dairy goats were divided into three groups. They were fed with concentrate mixtures containing soya bean meal (Control; n=9), ELS (n=10) or PSC (n=9) as main protein sources in the trial lasting 75 days. Addition of ELS or PSC did not influence milk yield and milk gross composition in contrast to fatty acid profile compared with Control. Supplementation of ELS resulted in greater branched-chain fatty acids (BCFA) and total n-3 fatty acids compared with Control and PSC (P<0.05). Total n-3 fatty acids were accompanied by increased α-linolenic acid (ALA, C18:3n-3; 0.56 g/100 g fatty acids) and EPA (C20:5n-3; 0.12 g/100 g fatty acids) proportions in milk of the ELS group. In contrast, ELS and PSC resulted in lower linoleic acid (LA, C18:2n-6; 2.10 and 2.28 g/100 g fatty acids, respectively) proportions compared with Control (2.80 g/100 g fatty acids; P<0.05). Abovementioned resulted in lower LA/ALA ratio (3.81 v. 7.44 or 6.92, respectively; P<0.05) with supplementation of ELS compared with Control or PSC. The PSC diet decreased total n-6 fatty acids compared with the Control (2.96 v. 3.54 g/100 g fatty acids, P<0.05). Oleic acid (c9-C18:1), CLA (c9,t11-18:2) and t10-,t11-C18:1 did not differ between treatments (P⩾0.08), although stearic acid (C18:0) increased in ELS diets compared with Control (12.7 v. 10.2 g/100 g fatty acids, P<0.05). Partially substituted soya bean meal with ELS in hay-based diets may increase beneficial n-3 fatty acids and BCFA accompanied by lowering LA/ALA ratio and increased C18:0. Pumpkin seed cake completely substituted soya bean meal in the diet of dairy goats without any decrease in milk production or sharp changes in fatty acid profile that may have a commercial or a human health relevancy.     

黑水虻幼虫氨基酸及其微量元素分析

黑水虻具有较高的营养价值,是一种重要的环境友好型资源昆虫.本研究采用凯氏定氮法、茚三酮柱后衍生离子交换色谱法和微波消解-电感耦合等离子质谱法(ICP-MS)等多种分析技术,测定了厨余垃圾饲喂的黑水虻幼虫蛋白质、氨基酸和微量元素的组成及含量.研究结果表明,黑水虻幼虫中蛋白质的含量为40.60 g/100 g.在测定的16...