苦瓜干制前后氨基酸组分的变化

经酸水解,利用氨基酸自动分析仪测定干制加工前后的苦瓜中总氨基酸和游离氨基酸含量。结果表明干制前后的苦瓜在氨基酸质量分数上有明显差别,总氨基酸质量分数分别为11.99%和10.87%,游离氨基酸分别为2.36%和0.70%。结论:干制前后的苦瓜中氨基酸质量分数差别明显,其中碱性氨基酸质量分数的变化尤其显著,总氨基酸中精氨酸质量分数下降50%,在游离氨基酸中下降78%;同时还原糖质量分数也由干制前的4.86%下降为干制后的1.86%,说明苦瓜干制过程中发生了美拉德反应,造成了氨基酸和还原糖含量的下降。     

龟板炮制前后氨基酸的分析

<正> 龟板系龟科动物鸟龟(Chinemgs ree-vsii)的腹甲,为传统滋补中药,具有滋阴潜阳,益肾强骨,养心补血的功效,主要有效成分为多种氨基酸。龟板一般按药典规定的方法经炮制后作为药用。有关氨基酸的系统分析,国内外尚未见报导。为了探讨龟板的内在质量、同时比较其炮制前后氨基酸含量的变化,我们对龟板中所含游离氨基酸及其水解后的氨基酸进行了分析研究。分析结果表明,炮制前的样品中含有I7种游离氨基酸,炮制后则只含有15种游离氨基酸,且前者含量明显高于后者;龟板炮制前后的样品经盐酸水鲜后均测得17种氨基酸,且前者含     

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。     

龙眼肉干制过程氨基酸组分分析

利用氨基酸自动分析仪分别测定加工前后的龙眼肉中的总氨基酸和游离氨基酸含量。结果,干制前后龙眼肉的氨基酸种类没有差别,但含量有明显差别,多数氨基酸的含量在干制后明显下降。结论:除丙氨酸和甲硫氨酸外,干制后的龙眼肉中的总氨基酸和游离氨基酸含量比干制前有明显下降,其中以碱性、酸性氨基酸含量的下降尤其显著。该差异可能是由于干制过程中发生美拉德反应造成的。     

生地黄与熟地黄中5个苷类成分和总多糖的含量比较

建立测定地黄中梓醇、地黄苷D、益母草苷、毛蕊花糖苷和异毛蕊花糖苷及总多糖含量的方法,比较生地黄与熟地黄中成分含量的差异。采用HPLC法同时测定了生地黄和熟地黄中梓醇、地黄苷D、益母草苷、毛蕊花糖苷和异毛蕊花糖苷的含量。采用UV法测定了生地黄和熟地黄中总多糖的含量。结果表明,生地黄炮制成熟地黄后,梓醇、地黄苷D、益母草苷和毛蕊花糖苷的含量均出现不同程度的降低,而异毛蕊花糖苷和总多糖的含量增加。本文所建立的同时测定梓醇、地黄苷D、益母草苷、毛蕊花糖苷和异毛蕊花糖苷含量的方法及总多糖的含量测定方法,可用于控制生地黄和熟地黄的质量。不同炮制方法对熟地黄中上述成分的含量产生一定影响。     

板蓝根热加工过程中氨基酸组分分析

利用氨基酸自动分析仪对板蓝根的新鲜植物组织和不同加工程度的板蓝根药材中的总氨基酸和游离氨基酸含量进行测定。结果表明:板蓝根的新鲜植物组织和不同加工程度的板蓝根药材氨基酸在含量上有明显差别。结论为:不同加工程度的板蓝根药材中氨基酸含量差别明显,其中碱性氨基酸含量的差别尤其显著,该差异可能是由于加工过程中发生美拉德反应造成的。     

山药品种间氨基酸含量的差异性研究

采用盐酸水解法分析了福建省建阳主栽的7个山药品种的氨基酸含量及组成。得出供试材料中都含有17种氨基酸,总氨基酸质量分数在2.86~6.64%,平均4.95%,其中以JY-4品种总氨基酸质量分数最高,JY-2最低;各种氨基酸质量分数高低顺序基本相似,以精氨酸、谷氨酸、天冬氨酸居前三位,胱氨酸质量分数最低,必需氨基酸质量分数的高低依次是亮氨酸>苯丙氨酸>赖氨酸>缬氨酸>异亮氨酸>苏氨酸>蛋氨酸;鲜味氨基酸在各品种间的差异显著,以JY-4最高,达3.41%,依次是JY-3、JY-6、JY-1、JY-5、JY-7、JY-2。再运用聚类分析方法从氨基酸的组成及含量角度对7个品种进行分类可分为三类;相关分析表明:山药总氨基酸含量愈高,必需氨基酸和鲜味氨基酸含量亦愈高。     

不同产地川乌炮制前后差异性成分研究北大核心CSCD

为建立川乌及制川乌的高效液相色谱(HPLC)指纹图谱,并结合化学计量学方法和主成分含量测定和比较3个不同产地川乌炮制前后的差异成分。该文采用HPLC法,利用中药色谱指纹图谱相似度评价系统(2012版)计算相似度,并结合聚类分析(HCA)、主成分分析(PCA)、偏最小二乘判别分析(PLS-DA)、正交偏最小二乘判别分析(OPLS-DA)及主成分含量测定结果进行综合分析。结果表明:(1)建立了3个产地15批川乌炮制前后的HPLC指纹图谱,分别标定了25个和14个共有峰,并通过对照品指认出6个共有峰,分别为苯甲酰新乌头原碱(峰16)、苯甲酰乌头原碱(峰17)、苯甲酰次乌头原碱(峰18)、新乌头碱(峰21)、次乌头碱(峰22)、乌头碱(峰23)。(2)化学计量学方法分析显示,川乌炮制前后的30批样品被明显分为2类,15批川乌被分为3类,15批制川乌被分为3类,新乌头碱、次乌头碱等6个成分可能是不同产地川乌炮制前后的潜在差异成分。(3)炮制前后主成分含量测定结果均有不同程度的变化,四川江油所产川乌炮制前后部分成分含量明显高于另外两个产地所产川乌。该研究建立的指纹图谱精密度、重复性、稳定性均较好,结合化学计量学分析方法和主成分含量测定分析,可为不同产地川乌炮制前后质量控制提供参考。     

不同品种魔芋精粉中氨基酸含量分析研究

花魔芋和白魔芋精粉中均含有 18种水解氨基酸和 18种游离氨基酸 ,前者水解氨基酸的总量为 2 .4 4 % ,其中必须氨基酸质量分数为 0 .6 2 % ,游离氨基酸总量为 1.10 % ,其中游离必须氨基酸质量分数为 0 .33% ;后者水解氨基酸总量为 2 .0 1% ,其中必须水解氨基酸质量分数为 0 .5 6 % ,游离氨基酸总量为 0 .4 1% ,其中必须游离氨基酸质量分数为 0 .13%。提示白魔芋和花魔芋精粉中氨基酸含量略有差异 ,但此差异不大 ,其品质 ,营养价值及特性等主要取决于魔芋精粉中主要成分葡甘聚糖的含量     

谷氨酰胺活性肽营养液对大鼠小肠营养作用的研究

用氨甲蝶呤诱发小肠炎后 ,SD大鼠分别饲喂Gln含量不等的氨基酸营养液 ,结果表明 ,72h内 ,第一组 (零剂量组 )大鼠的死亡率为 6 6 .7% ,第二组 (含Gln质量分数 2 % )为 16 .7% ,第三组 (活性肽组 ,含Gln质量分数 2 0 % )和第四组 (结晶氨基酸液 ,含Gln质量分数 2 0 % )为 0 ,并且第三组和第四组的体重、蔗糖酶活、氨肽酶活、DNA和RNA的含量增加 ,说明Gln活性肽营养液对小肠具有明显的营养作用。     

Effect of season and artificial diet on amino acids and nucleic acids in gonads of green sea urchin Strongylocentrotus droebachiensis

The content of total and free amino acids (FAA) in green sea urchin (Strongylocentrotus droebachiensis) gonads varied with the season and feeding on an artificial diet. Glycine was the dominant amino acid in each season contributing 12.9-16.6% to the total amino acid (TAA) content, peaking in the spring. In the FAA profile, glycine accounted for 30.3-61.4% in different seasons. A grain-based artificial diet had noticeable effects on the total and FAA compositions of S. droebachiensis. Although, glycine was the dominant amino acid in the TAA profile during early harvesting, tyrosine in gonads became more dominant on week 9 of feeding. Furthermore, glycine was the dominant amino acid in the FAA pool after feeding the artificial diet. The total FAA content in the gonads increased significantly (P<0.05) from 20.6 on week 0 to 180.6 mg/g dry mass tissue on week 3. There were no significant (P<0.05) changes between week 6 and week 9. Deoxyribonucleic acid (DNA) content exceeded that of ribonucleic acid (RNA) in each season, while in cultured urchins, RNA content exceeded that of DNA only on week 6. The RNA/DNA ratio was significantly increased in the summer, whereas this ratio was increased up to week 6 followed by a decrease on week 9 in cultured counterparts.     

Seasonal patterns of nucleic acid concentrations and amino acid profiles of Parapenaeus longirostris (Crustacea, Decapoda): relation to growth and nutritional condition

The present work describes the seasonal changes in nucleic acid concentrations and amino acid profiles in the muscle of juvenile Parapenaeus longirostris and their relation to growth and nutritional condition. RNA content varied significantly between seasons, being the highest values attained in spring and the lowest in winter (p < 0.05). Similar results were obtained with RNA:protein and RNA:DNA ratios. In respect to total amino acid content (TAA), a significant increase from winter to spring was observed (p < 0.05) and the major essential amino acids (EAA) were arginine, histidine and leucine. Within non-essential amino acids (NEAA) glutamic acid, aspartic acid, glycine and proline were dominant. From winter to spring, a significant variation in NEAA content occurred (26.8; p < 0.05), mainly due to the significant increase of glutamic acid (79.1) and serine (66.7) (p < 0.05). EAA content did not vary significantly between seasons (p > 0.05). In opposition, during this period a significant decrease in the free amino acid content (FAA) was observed (p < 0.05); a higher percentage of decrease was attained in free non-essential (FNEAA – 42.9) in comparison to free essential amino acids (FEAA – 40.2). The significant increase in RNA and TAA contents from winter to spring may be related with protein synthesis. On the other hand, the lowest values obtained in winter may be due to a reduction in feeding activity; in this period the muscle protein must be progressively hydrolysed, which is evident with the higher FAA content. The liberated amino acids enter FAA pool and become available for energy production. In conclusion, it was evident that the seasonal cycle in activities such as feeding and growth with nucleic acids and amino acid analyses was noticed.     

河蚬汤中氨基酸组分的分析

利用全自动氨基酸分析仪测定了传统保肝食品--河蚬汤中的总氨基酸和游离氨基酸含量.结果表明,河蚬汤中含有17种常见(色氨酸在酸解时遭破坏)氨基酸,还有鸟氨酸和牛磺酸两种非蛋白质组成氨基酸,总含量为297.4 mg·g-1.其中鸟氨酸含量最高,占总氨基酸的12.4%,且87%的鸟氨酸以结合态形式存在.河蚬汤中游离氨基酸含量...     

测定荔枝核中的游离氨基酸

采用氨基酸自动分析仪测定荔枝核水提取液、醇提取液样品。在醇提取液中游离氨基酸的含量高于水提取液,在两种提取液中共检出了21种游离氨基酸(其中4种为未知氨基酸,6种必需氨基酸);已知游离氨基酸的质量分数为307μg.kg-1(醇提取液)和269μg.kg-1(水提取液),总游离氨基酸的质量分数为500μg.kg-1,必需氨基酸的量占总游离氨基酸量的44%。结论:荔枝核中的游离氨基酸具有利用价值。     

百合中氨基酸组成测定与营养功能分析

以3种不同的百合为原料,用水浸提法提取百合中游离氨基酸,对提取条件进行研究,通过正交试验确定最适宜提取条件(即:以7.5%乙酸为提取液,料液比1:35,70℃提取3 h).同时采用氨基酸分析仪测定3种百合的水提取液样品,共检出17种游离氨基酸(其中7种为必需氨基酸).结果表明,百合中的游离氨基酸以精氨酸为主体,占总游离...     

生产工艺对乌龙茶中咖啡因含量的影响

目的:为研究乌龙茶生产工艺对其咖啡因含量的影响。方法:利用紫外分光光度法测定各个生产工序的安溪乌龙茶本山品种半成品中咖啡因含量。结果:安溪乌龙茶本山品种成品相对其他工序的半成品而言,咖啡因含量明显增多,比鲜叶提高了16.1%。结论:生产工艺尤其是加热对安溪乌龙茶本山品种中咖啡因含量有较大影响。     

Changes in free amino acids in the hemolymph of giant freshwater prawn Macrobrachium rosenbergii exposed to varying salinities: relationship to osmoregulatory ability

Changes in free amino acids (FAA) in the hemolymph of the giant freshwater prawn, Macrobrachium rosenbergii, were examined in individuals exposed to varying salinities for up to 1 week. In freshwater and under conditions of low salinity, total FAA concentrations were maintained between approximately 0.85 and 1 mM and did not exhibit changes in response to salinity exposure. Under high salinities, total FAA concentrations increased dramatically, reaching up to 2.1 mM depending on treatment. Examination of individual amino acid concentrations revealed that these increases were based on specific changes in glycine, arginine, alanine, proline and lysine. Among these, alanine showed the greatest increases, resulting in levels six-fold higher under high salinity than in freshwater and under low salinity. The other amino acid species showed increases of 2.5-fold compared to original values. These five FAAs in freshwater and under low salinity together occupied approximately 45% of total FAA contents and under high salinity comprised more than 70% of total FAA contents. These results suggest that specific hemolymph FAAs are involved in mediating response to salinity exposure in freshwater prawns.