紫荆花中氨基酸的测定与营养学评价

利用氨基酸自动分析仪测定了紫荆花中的17种氨基酸。结果表明,氨基酸含量为9.9%,其中必需氨基酸占总氨基酸的比值为37.57%,必需氨基酸与非必需氨基酸的比值为60.18%。结果显示,紫荆花中的氨基酸较高,具有很高的开发利用价值。     

辽刺参不同部位氨基酸及牛磺酸含量分析

对辽刺参内容物(肠、性腺、呼吸树)的氨基酸及牛磺酸成分进行含量测定分析。样品采用盐酸水解法处理,使用柱前衍生化反相高效液相色潽法对18种氨基酸及牛磺酸成分含量进行测定。并对其18种氨基酸含量与联合国联农组织/世界卫生组织FAO/WHO公布的标准氨基酸模式进行比较,计算氨基酸评分AAS、化学分CS、必需氨基酸指数EAAI、营养指数NI,综合评估辽刺参内容物(肠、性腺、呼吸树)蛋白质的营养价值。其中辽刺参内容物的18种氨基酸成分中必需氨基酸占氨基酸总量的比值(E/T值)为39%～44%,必需氨基酸与非必需氨基酸的比值(E/N值)为63%～75%,辽刺参内容物E/N值、E/T值均高于FAO/WHO理想蛋白质标准。必需氨基酸比例高于辽刺参体壁,辽刺参内容物中牛磺酸含量远高于辽刺参体壁。辽刺参内容物蛋白质营养评价较海参体壁更高,具备较大的保健食品开发价值。     

两种豆类植物蛋白的特征氨基酸组成和消化特性

以野生山毛豆和大豆为原料,通过氨基酸分析和体外模拟实验研究了两种豆类植物蛋白的特征氨基酸组成和消化特性。结果表明:山毛豆含有丰富的蛋白质和氨基酸,脱脂后的山毛豆中蛋白质含量约为47.12%±0.35%,大豆中蛋白质含量约为44.17%±0.48%。两种豆类中均含有18种氨基酸,其中包含人体必需的8种氨基酸,山毛豆氨基酸总量为38.08%,必需氨基酸含量为13.47%,非必需氨基酸含量为24.61。山毛豆氨基酸中支链氨基酸占总氨基酸量的15%大豆所含的支链氨基酸占总氨基酸量的13%。山毛豆和大豆的蛋氨酸为第一限制氨基酸,缬氨酸为第二限制氨基酸,AAS值有一定差异。山毛豆蛋白属于优质蛋白。模拟体外消化表明山毛豆蛋白体外消化率为88.86%±0.75%,大豆蛋白体外消化率为91.71%±0.88%,无显著差异。     

高效液相色谱法测定发酵酱油中的氨基酸含量及分析

采用高效液相色谱法分析了两种发酵酱油中的氨基酸。结果表明,低盐固态发酵酱油与高盐稀态发酵酱油中均含有丰富的氨基酸,8种必需氨基酸含量比例分别达到46.05%与41.45%。虽然低盐固态发酵酱油的总氨基酸与必须氨基酸的含量高于高盐稀态发酵酱油,但高盐稀态发酵酱油中呈味氨基酸特别是甜味和鲜味氨基酸的含量较高,从而使高盐稀态发酵酱油滋味更加鲜美。     

4种鸡汤中游离氨基酸的组成及呈味贡献对比分析

将鸡肉煮汤,经离心、冷冻干燥后,利用氨基酸自动分析仪进行游离氨基酸的测定及呈味分析,研究了北京油鸡、三黄鸡、奔跑鸡、散养鸡的鸡汤中游离氨基酸的种类及对呈味的贡献。4种鸡汤中均鉴定出17种游离氨基酸,其中必需氨基酸7种,含量最高的是组氨酸。总氨基酸含量最高的是散养鸡汤(46.47 g/L),最低的是三黄鸡汤(16.86 g/L)。必需氨基酸总含量最高的是散养鸡汤(10.02 g/L),最少的是三黄鸡汤(3.88 g/L)。4种鸡汤中苦味氨基酸各为9种,鲜味2种,甜味5种,鲜味氨基酸质量分数最高的为三黄鸡汤(18.42%),甜味氨基酸质量分数最高的为奔跑鸡汤(30.41%)。根据氨基酸滋味活性值(TAV)得出,北京油鸡汤中对滋味有贡献的氨基酸为11种,三黄鸡汤6种,奔跑鸡汤10种,散养鸡汤11种。通过电子舌主成分分析(PCA)和判别指数,表明差异最小的是奔跑鸡汤和三黄鸡汤,最大的是散养鸡汤和北京油鸡汤。     

刺儿茶营养成分分析与评价

研究刺儿茶的营养成分。仿照茶叶加工工艺制备刺儿茶,按相关国标与方法测定其茶多酚、咖啡因、多糖、粗蛋白质、粗脂肪、粗纤维、维生素、氨基酸及矿质元素等含量。结果显示:刺儿中茶多酚、咖啡因、多糖、粗蛋白质、粗脂肪及粗纤维含量分别为11.3%、7.8%、6.1%、5.6%、2.1%、14.4%,茶多酚、咖啡因、多糖含量均高于绿茶中含量。其含有8种必需氨基酸中以色氨酸含量最高(1.22 g/100 g),必需氨基酸占总氨基酸的47.80%。刺儿茶中所含维生素以V_C含量最高(19.13 mg/100 g),含量略高于绿茶中Vc含量(18.60 mg/100 g),其V_(B1)(1.32mg/100g)含量显著高于绿茶中V_(B1)(0.02 mg/100 g)含量。但刺儿茶V_E、V_(B2)、V_(B3)、V_(B6)含量低于绿茶中V_E、V_(B2)、V_(B3)、V_(B6)的含量。矿质元素中Se含量丰富(6.2μg/100 g)为绿茶Se含量(3.1μg/100 g)的2倍。刺儿茶有较高的营养价值。     

假奓包叶氨基酸提取纯化工艺及其氨基酸组成分析

用响应面法考察假奓包叶氨基酸提取最佳工艺并确定其氨基酸组成,以氨基酸提取率为评价指标,通过单因素和响应面实验优化其工艺条件并进行氨基酸分析。在盐酸浓度6.1 mol/L,液料比〔即溶液用量(mL)与原料质量(g)的比值,下同〕21.6∶1,水解时间22.3 h,水解温度100℃条件下,氨基酸的提取率为11.21%。再经活性炭脱色、离子交换树脂纯化后得到假奓包叶氨基酸产品。氨基酸分析结果表明,假奓包叶氨基酸产品中总氨基酸质量分数为79.7%,其中必需氨基酸的质量分数达24%,可作为功能性食品或药品的营养添加剂应用。     

栅藻藻渣营养成分分析及蛋白提取工艺优化

研究了二形栅藻藻渣的蛋白提取工艺及氨基酸组成,在测定藻渣蛋白等电点的基础上考察了浸提液pH值、液料比、浸提温度与时间对蛋白提取率的影响. 由正交实验得出提取藻渣蛋白的最佳工艺条件为：浸提液pH值12、液料比40 mL/g、浸提温度45℃、浸提时间140 min,该条件下藻渣蛋白提取率为40.13%. 所制藻渣蛋白氨基酸种类齐全,比例均衡,可作为理想的人蛋白来源. 必需氨基酸占氨基酸总量的44.3%. 蛋白质的必需氨基酸指数、氨基酸评分、化学评分、生物价、营养指数和氨基酸比值系数评分分别为82.24, 63.32, 46.66, 77.94, 35.84和74.21.     

离子交换色谱法测定注射用双黄连(冻干)中氨基酸的含量

应用氨基酸自动分析仪,采用离子交换色谱-柱后衍生化法,测定注射用双黄连(冻干)样品、中间体及其药材中游离和水解后的氨基酸的含量。结果显示,注射用双黄连(冻干)成品3批样品中游离氨基酸含量分别为0.46%,0.38%,0.37%,总氨基酸含量分别为1.30%,1.40%,1.20%;金银花中间体中游离氨基酸和总氨基酸含量分别为1.07%和3.36%,黄芩中间体中游离氨基酸和总氨基酸含量分别为0.01%和0.1%,连翘中间体中游离氨基酸和总氨基酸含量分别为0.05%⁰.85%;金银花药材中游离氨基酸和总氨基酸含量分别为0.88%和9.40%,黄芩药材中游离氨基酸和总氨基酸含量分别为0.26%和4.73%,连翘药材中游离氨基酸和总氨基酸含量分别为2.83%和5.86%,该实验结果为注射用双黄连(冻干)质量标准的提高提供了参考依据。     

云南元宝枫茶营养成分分析

对云南元宝枫茶的化学成分进行分析测定。结果表明,元宝枫茶粗蛋白含量为13.42%,氨基酸为11.79g/100g干叶;必需氨基酸占氨基酸总量的41.48%。单宁含量10.82%。SOD含量91.40μg/g鲜叶。VE含量14.13mg/100g鲜叶。总黄酮含量4.13%,绿原酸含量2.38%。矿质元素含量丰富,尤其是Ca,K等,并具有十分典型的高钾低钠特点。有较高的营养价值及医疗保健作用。     

茚三酮比色法测定CMA馏出物中氨基酸含量的研究

采用茚三酮比色法对木醋液制备环保型融雪剂过程中的馏出物中氨基酸进行分析,结果表明,馏出物中氨基酸的含量约为1.4 g/L,且不受活性炭用量的影响,馏出物应调整到弱酸性条件(pH=4左右),才能保证稳定的氨基酸含量.研究结果可为植物生长促进剂的开发提供理论依据,并将促进木醋液的综合利用和生物质能的开发.     

The uptake and distribution of mineral nutrients in the banana in response to supply of K,Mg and Mn

The effects of differential K, Mg and Mn supply on the uptake and distribution of N, P, K, Ca, Mg, Na, Mn, Cu and Zn in the Williams banana were examined over the three crop cycles. Plants were grown in sand culture in 1 m³ drainage lysimeters.In terms of total plant uptake the standard solutions used were balanced in respect of P, K and Ca, possibly low in Mg and high in Mn, Cu and Zn compared with field grown plants. K and Mg supply influenced total plant uptake of most elements similar to the way they influenced dry matter production. Exception were total plant uptake of Mg and Cu. High Mn supply depressed the uptake of Mg and Cu and increased the uptake of Mn sevenfold.Increase in K supply reduced the proportion of all nutrients, except K, retained in the roots and increased the proportion located in the fruit. A large proportion (20–36%) of N, P and K were located in the fruit, Ca, Mg and Mn accumulated in the trash (29–44%) and roots were high in Na, Cu and Zn (29–50%).     

沙虫中营养元素和常规营养成分分析

应用火焰原子吸收光谱法测定了沙虫中Zn、Cu、Mn、Fe、Mg、Ca等6种营养元素的含量,并对其中的粗蛋白质、粗脂肪、总糖和水分等常规营养成分进行了测定。结果表明,沙虫中含有丰富的Ca、Mg、Cu、Mn等微量元素,营养成分含量中,粗蛋白含量为24.35%,粗脂肪含量为2.23%,总糖含量为4.91%,水分含量为88.91%,粗蛋白质含量明显高于粗脂肪和总糖含量,属高蛋白、低脂、低糖型水产资源。     

培养条件对产朊假丝酵母合成谷胱甘肽的影响

考察了培养基组成,培养条件对产朊假丝酵母生长和谷胱甘肽合成的影响,包括不同碳源,氮源及其浓度,pH,装液量,接种量等。确定以葡萄糖、磷酸氢二铵作为碳源和氮源,较佳浓度分别为20g/L和3g/L,接种量为10％,在20 g/L 的糖 浓度时获得的谷胱甘肽总量可达74mg/L,胞内含量为1.4％左右。此外还研究了三种前体氨基酸和ATP的加入量,加入时间对发酵的影响。     

4种酸菜呈味成分的分析

为对比分析了4种酸菜中游离氨基酸、有机酸、核苷酸的含量及呈味特性,采用高效液相色谱仪对其进行分离鉴定,通过计算味道强度值确定了各呈味成分对酸菜滋味的贡献。结果表明:4种酸菜中呈鲜味的门冬氨酸含量最高,占总游离氨基酸含量的46.00%～53.21%,其次为呈苦味的精氨酸和呈甜味的丙氨酸;酸菜样品1、3和4中的乳酸含量最高,分别占总有机酸含量的41.69%、30.96%和38.76%,其次为乙酸、草酸;样品2中有机酸含量排名前3位的分别为草酸、乳酸和乙酸。样品1中核苷酸含量最高为0.0556 mg/g,其次为样品2中核苷酸含量0.0516 mg/g。味道强度值分析发现,4种酸菜中门冬氨酸、草酸、甲酸、乳酸、乙酸、柠檬酸、琥珀酸的味道强度值均大于1,对酸菜滋味的贡献较大。     

Characterization of the Seed Oil and Meal from <Emphasis Type="Italic">Monechma ciliatum</Emphasis> and <Emphasis Type="Italic">Prunus mahaleb</Emphasis> Seeds

The oil and meal from Monechma ciliatum (black mahlab) and Prunus mahaleb (white mahlab) seeds were characterized for their physicochemical properties. The oil content was found to be 30.95 and 13.15% in white and black mahlab seeds, respectively. The refractive indices of white mahlab oil (WMO) and black mahlab oil (BMO) were 1.475 and 1.470, and specific gravities were 0.8511 and 0.8167 g/cm³, respectively. Saponification values were 184.23 and 180.3 mg KOH/g, peroxide values were 2.54 and 4.43 meq/kg, and unsaponifiable matter was 0.92 and 0.66%, respectively. The major fatty acids were palmitic 4.5%, stearic 16.0%, oleic 47.3%, and linoleic 31.4% in BMO, while in WMO they were palmitic 5.7%, oleic 45.0%, and linoleic acid 47.0%. A moderate amount of tocopherols were found at 45.2 and 28.5 mg/100 g in BMO and WMO, respectively. Protein content was found to be 21% in black and 28% in white mahlab seeds. The total amount of amino acids in black and white mahlab seeds was found to be 783.3 and 1,223.2 mg/g N, respectively. The concentration (on ppm dry-weight basis) of major elements (Ca, K, and Mg) and of minor elements (Al, Pb Ni, Mn, Cu, Cr, Co, and Fe) was also determined in the meals.     

Investigation of Oil and Protein Contents of Eight Sudanese Lagenaria siceraria Varieties

The composition of the oil and protein contents of eight Lagenaria siceraria varieties was characterized in order to evaluate their suitability as a source of edible oil and protein. The physicochemical properties and fatty acids of seed oils were determined. The oil yield ranged from 24.11 to 26.32 %. The refractive indices and relative densities of the oils fell within the narrow ranges of 1.464–1.468 and 0.857–0.907 g/cm³, respectively. The saponification value ranged from 158.48 to 179.52 mg KOH/g, unsaponifiable matter was between 0.749 and 0.937 %, and the peroxide values were lower than Codex values for vegetable oils. The principal fatty acids were linoleic (62.1–67.9 %), oleic (11.54–15.46 %), palmitic (12.13–14.03 %), and stearic (6.71–7.71 %) acids. Low linolenic acid levels were also observed (<1 %) within the range of 0.32–0.44 %. The major essential amino acids were arginine (2.04–3.77 g/100 g), leucine (1.245–1.726 g/100 g), phenylalanine (0.803–1.396 g/100 g), and lysine (0.921–1.383 g/100 g). The non‐essential amino acids were glutamic acid (2.5–4.37 g/100 g), aspartic acid (1.39–2.36 g/100 g), serine (0.69–1.19 g/100 g), glycine (0.79–1.37 g/100 g), alanine (0.72–1.37 g/100 g), and proline (0.63–1.02 g/100 g). Nine minerals (Na, Ca, Mg, K, Cu, Fe, Mn, Zn, and P) were determined with significant (p < 0.05) differences. The studied oils showed promising results and can be used in the food, cosmetics, and pharmaceutical industries. This is the first study on the eight L. siceraria seed varieties grown in Sudan, opening the way for further studies on these seeds.     

Vitamins and minerals from sardine in tomato sauce, from the Mexican Pacific fish zones

Sardine is a sea food widely consumed in Mexico due to it's abundance and very low price. Its content in vitamins, minerals and chemical composition were evaluated in its canned presentation in tomato sauce. Samples proceeded from 3 fishery areas of the Mexican Pacific: (L1) Baja California Sur, (L2) Sonora and (L3) Sinaloa. The proximal chemical analysis was carried out by the AOAC methods; mineral content (Ca, Mg, Na, K, Fe, Zn, Cu, Cd, Cr, Pb) was determined by atomic absorption spectrophotometry and vitamins A, B1, B2 and niacin were quantified by HPLC. Results showed a high moisture content from 69 to 82%, ether extract ranged between 7.8% (L2) and 10.2% (L3) and crude protein content between 10.6% (L3) and 14.6% (L1). Vitamin A (IU/100 g) was similar for all samples: L1 (63-66); thiamin (mg/100 g) was high in L1 (0.13) and low in L3 (0.09); riboflavin was high in L1 (0.15) and showed values of 0.13 for both L2 and L3; niacin content was high in all samples: L1 (2.24), L2 (1.48) and L3 (1.75). Minerals were abundant (mg/100 g) in Na, K, and P; L1 showed a great variation for Na (363-636) compared with L2 and L3 (250); K was very variable among the samples: L1 (597), L2 (100) and L3 (57). Phosphorous and magnesium had small variations: P (229, 243 and 212) and Mg (28, 23 and 23) for L1, L2 and L3. Iron was more abundant in L1 (5.5) and L3 (4.3); Zn was higher in L2 (3.4) and similar in L1 (2.5) and L3 (2.2). Copper showed a great variation in L2 (0.21-0.48) but the averages were similar (0.37, 0.35, 0.33, for L1, L2 and L3 respectively). Finally, heavy metal content was lower than 0.002 mg/100 g. In conclusion, there are some variation in Ca, Na, K, thiamin and niacin content in canned sardine with tomato sauce, depending upon the fishing area.