大麦苗粉中氨基酸组成及含量

对大麦苗粉中的氨基酸进行了定性、定量分析研究。结果表明:大麦苗粉中共分析检测出26种氨基酸,其中,水解氨基酸17种,游离氨基酸26种。大麦苗粉中17种水解氨基酸总含量为9 163.422mg/100g,其中人体必需氨基酸含量占总含量的40%以上,大麦苗粉中含有9种药用氨基酸,其中Glu含量最高,达1 390.873mg/100g;大麦苗粉中26种游离氨基酸总含量为983.852 mg/100g;其中Asp、Glu、Arg、Pro、His、Val 6种游离氨基酸,是形成大麦苗粉风味的主要氨基酸。     

配施饼肥对烤烟叶片含氮化合物代谢及酶活性的影响

通过饼肥用量盆栽试验,研究了K326中部叶在不同生育时期硝酸还原酶和中上部叶片含氮化合物总氮、烟碱、可溶性蛋白质和游离氨基酸含量的变化规律.结果表明,硝酸还原酶随着有机肥施用量的增加酶活性呈增加趋势,中上部叶片的总氮和烟碱含量随有机肥的增加呈上升的趋势,而蛋白质含量则呈下降的趋势,有机肥可以促进游离氨基酸含量的提高.     

Analysis and metabolite profiling of glucosinolates,anthocyanins and free amino acids in inbred lines of green and red cabbage (Brassica oleracea L.)

We profiled and quantified glucosinolates (GSLs), anthocyanins and free amino acids in thirty-seven inbred lines green and red cabbage. Analysis of these distinct cabbages revealed the presence of 8 GSLs, 13 anthocyanins and 12 free amino acids. GSL contents were varied among the different lines of cabbage. The maximum levels of glucoraphanin (14.91 μmol/g DW) and glucobrassicin (12.37) were found in FX 1-28 and FX 1-32 lines, respectively. Total GSLs in red cabbage lines were 50% higher than those of green cabbage. Anthocyanin contents in red cabbage were ranged from 4.11 to 6.81 mg/g DW in FX 2-3 and FX 1-34 lines, respectively. Among the 13 anthocyanins, both cyanidin 3-(feruloyl) (sinapoyl)diglucoside-5-glucoside and cyanidin 3-(sinapoyl) (sinapoyl)diglucoside-5-glucoside levels were the highest amounts. The amounts of total free amino acids were ranged from 523.5 to 1308 mg/100 g fresh weight (FW) in green cabbage and 484.8 to 1271 in red cabbage, respectively. In red cabbage lines, 9.4% of the total free amino acids accounted essential amino acids such as valine, threonine, isoleucine, leucine and lysine. Thus, the amounts of GSLs, anthocyanins, and amino acids varied widely, and the variations in these compounds between the lines of cabbage were significant.     

Varietal and geographic classification of French red wines in terms of elements,amino acids and aromatic alcohols

Thirty-four French red wines from three regions already studied for their anthocyanin and flavonoid constituents have been further analysed for elements, amino acids and aromatic alcohols. An interpretation of the differences between wines related to their different geographic and varietal origins has been made from the results of statistical analyses: F statistic, principal component analysis (PCA) and stepwise discriminant analysis (SDA). Wine samples produced near Bordeaux were found to be characterised by higher rubidium and lower lithium and calcium concentrations. Differences between wine samples made from the same grape variety or produced in the same region are mainly related to differences in potassium and ash contents. The PCA demonstrates that the concentration of most amino acids in wines is mainly a function of the technology used in wine production. Moreover, it shows that the concentration of proline, hydroxyproline and ethanolamine are generally lower in wines prepared from Carignan, Cinsault and Grenache grapes than in wines from Cabernet Franc, Cabernet Sauvignon or Merlot grapes. Finally, it shows clear differences between wines according to the latitude of the production centre. These differences correspond to increasing total nitrogen content from south to north, ie Narbonne and Bordeaux versus Angers. In discriminant analysis Bordeaux wines were characterised by high rubidium and low arginine concentrations, Angers wines by a lower arginine content and Narbonne wines by their abundance of magnesium and deficiency of ethanolamine.     

萌动小麦生化指标及Mixolab糊化特性的变化

分析了萌动小麦游离氨基酸、蛋白质、水溶性糖类和破损淀粉含量及Mixolab面团糊化特性的变化。小麦萌动后游离氨基酸总量显著增加,蛋白质含量(干基)也增加,Mixolab仪测定的C2稠度谷值、C3淀粉糊化黏度峰值、C4淀粉糊化黏度谷值、C5淀粉回生终点值均减小。小麦萌动前后,水溶性总糖含量、Bacillus amyloliquefaciens蛋白酶(含内切和外切酶)降解产生的游离氨基酸含量对试验的6个品种差异不显著;除1个品种外,试验的其他5个品种水溶性还原糖含量及Aspergillus melleus蛋白酶(仅含内切酶)酶解产生的游离氨基酸含量显著增加。不同品种小麦萌动前后破损淀粉含量增减不一致。结论为小麦发芽后游离氨基酸总量增加、Mixolab面团蛋白质网络弱化程度加大、淀粉糊化峰值和谷值均降低,可以作为芽麦检测的参考依据。