尼罗尖吻鲈鱼肉营养成分的测定及评价

<正>尼罗尖吻鲈(Lates niloticus)属鲈形目、锯盖鱼科、尖吻鲈属,原产非洲,分布在尼罗河流域、Mariout湖和西非的大部分主要河流。是生活在淡水或低盐度水体中的肉食性鱼类,也是世界上最大的淡水鱼之一。其最大体长接近2m,最大体重超过200kg,味道鲜美、无肌间刺。目前,仅见国外有饲养条件等因素对其肌肉营养成分影响的粗略报道[1]。我中心2003年在国内首次引进尼罗尖吻鲈,本研究旨在测定尼罗尖吻鲈鱼肉的营养成分,并对其营养价值进行评估。     

鱼鳞胶延缓D-半乳糖致衰老小鼠退行性变作用研究

<正>明胶是胶原蛋白的变性分解产物,在延缓机体退行性变,特别是在延缓皮肤衰老中的应用广泛[1]。但相关的现代科学研究仍然较少,至今尚无较全面系统的功效评价。罗非鱼是世界第二大养殖鱼种,广泛用于生鱼片和鱼糜制品的生产,其加工废弃物(鱼鳞)通常用来制备明胶并应用于食品行业[2]。本文从脏器指数、生理生化、形态结构等方面探讨罗非鱼鱼鳞胶(fish scale gelatin,FSG)延缓机体退行性变作用。     

4种罗非鱼中微量元素的主成分分析

运用主成分分析法,结合SPSS统计软件,对奥利亚、奥尼、尼罗、吉富4种罗非鱼的微量元素进行定量定性综合评价。在综合评价中,由第1、第2主成分的累计方差的贡献率达到了94.199%,开拓了科学地进行综合评价的新领域。     

不同生长阶段人工养殖史氏鲟肌肉主要营养成分的比较研究

<正>史氏鲟(Acipenser schrenckii Brandt),是中国现存鲟鱼中最具经济价值的鱼类,有个体大、成活率高、生长速度快、肉质鲜美等特点。鲟鱼最有价值的产品是鱼子酱,素有"软黄金"之称,因此史氏鲟养殖主要有商品鱼养殖和亲鱼养殖两种方式。商品鱼养殖,一般养殖时间为一年,体重约0.5¹.0 kg;亲鱼养殖是指史氏鲟在养殖31.0 kg;亲鱼养殖是指史氏鲟在养殖3⁴年辨出雌雄后,雄鱼淘汰作为商品鱼上市,体重约34年辨出雌雄后,雄鱼淘汰作为商品鱼上市,体重约3⁵ kg;雌鱼养殖至75 kg;雌鱼养殖至7⁸年用于生产鱼籽酱,取完鱼籽的鱼体俗称壳,也用作商品鱼上市。近几年,国内外对史氏鲟的研究逐渐展开,内容主要集中在人工繁殖技术[1]、生物化学[2]、遗传发育[3]、组织形态[4]等方面,对史氏鲟商品     

5种罗非鱼营养成分分析及评价

<正>罗非鱼是我国主要养殖水产品。其肉质鲜美,少刺,蛋白质含量高,富含人体所需的8种必需氨基酸,其中谷氨酸和甘氨酸含量特别高[1,2]。目前养殖和繁育体系较为完善的品种有奥利亚罗非     

长蛸肌肉主要营养成分分析及评价

<正>长蛸(Octopus variabilis),隶属于软体动物门,头足纲,八腕目,蛸科(Octopodidae),俗称长八带鱼、鲅须[1]。在我国南北海域均有分布,其中北部海域较多。长蛸个体大、肉质肥厚鲜美、营养丰富,富含蛋白质和氨基酸,可食用部分占总体的90%以上[2]。肉既可鲜食,又可加工成干制品,食用方式多样,具有较高的经济价值[3]。目前,已有学者对长蛸的生物学特征、生态习性及养殖技术等进行过研究[4-7],而关于长蛸肌肉营养成分的研究尚未见报道。本文拟采用生化测定方法,对我国大连近海长蛸肌肉中的生化组分进行研究,旨在为更清楚全面了解长蛸的营养价值提供理论依据。     

养殖鱼体邻苯二甲酸酯含量与分布特征

目的调查珠江三角洲及香港地区的养殖池塘3种淡水养殖鱼类(草鱼、鲫鱼和罗非鱼)体内6种邻苯二甲酸酯(PAEs)的含量与分布特征。方法于2005年11月在珠江三角洲和香港地区采集草鱼、鲫鱼、罗非鱼,鱼肉样品经冻干处理,索氏抽提,氧化铝-硅胶柱净化,气相色谱-氢火焰离子化检测器(GC-FID)检测。结果珠江三角洲地区鲫鱼、草鱼、罗非鱼体内邻苯二甲酸二异辛酯(DEHP)含量分别高达16.10、19.81和11.03 mg/kg(体重,干重);邻苯二甲酸二正丁酯(DBP)和邻苯二甲酸丁辛酯(BOP)在3种鱼类体内的含量在3～10 mg/kg之间。邻苯二甲酸二甲酯(DMP)的含量最低(0.54 mg/kg)。香港地区鲫鱼、草鱼、罗非鱼体内DEHP含量高达35.97、37.98、26.12 mg/kg,而DMP和DEP含量较低。结论养殖鱼类受PAEs的污染情况随地域的不同有较大差异,来自香港地区的养殖鱼类样品中6种PAEs含量高于珠江三角洲地区样品。     

四种罗非鱼营养成分的比较

<正>罗非鱼(Tilapia)原产地非洲,是我国主要养殖水产品,其主要特点为肉质鲜美,少刺,蛋白质含量高,深受消费者喜爱[1-2]。莫桑比克罗非鱼(Oreochromis mossambicus),上世纪五十年代称为越南鱼。1956、1957年分别由泰国和越南引入我国广东省试养,因其个体小、生长慢、体色黑,现已淘汰。荷那龙罗非鱼(O.hornorum),2001     

菲律宾蛤仔营养成分分析与评价

<正>菲律宾蛤仔(Ruditapes philippinarum)属软体动物门(Mollusca)、双壳纲(Veneroida)、帘蛤科(Veneridae)、蛤仔属(Ruditapes)[1],俗称花蛤、蚬子、杂色蛤等,为广温、广盐性贝类。我国北起辽宁,南至广西、海南都有分布[2]。目前年产量总产量的90%,约占我国海水养殖总量20%,占贝类养殖总量30%[3]。很多学者对菲律宾     

以色列市场鱼的气单胞菌和指示菌的检测

本次检测是为了评价在以色列养殖、供应的3种鱼的微生物学质量。这3种鱼分别是生活于水底受到严重有机污染的鲤鱼和罗非鱼,以及生活于细菌含量少的低温、流动、清洁水中的鳟鱼。样品及制备本次检测从1989年5月持     

油菜、蚕豆、柿子、梅花、紫云英和玉米等六种蜂花粉的游离氨基酸分析

<正> 蜂花粉是一种天然营养佳品,尤其是其中富含优质蛋白质。对蜂花粉蛋白质水解后氨基酸的分析,国内外报道较多。但花粉中能被人类直接吸收的游离氨基酸的分析,国内外报道甚少。本文旨在采用一种快速、经济、简便和灵敏度可达3×10~(-12)M的DANS-Cl荧光反应、聚酰胺薄膜层析方法。分析并制作了油菜等六种蜂花粉中游离氨基酸的含量及荧光层     

蛋白质营养价值评价——氨基酸比值系数法

氨基酸比值系数法是基于氨基酸平衡理论设计的评价蛋白质营养价值的方法。本文介绍了氨基酸比值系数(RC)和比值系数分(SRC)的计算和意义。RC用于判定限制氨基酸和计算限制氨基酸的强化量,SRC用于评价蛋白质营养价值。SRC与生物价(BV)之问有高度的相关性(P<0.001)。与FAO氨基酸模式计算的化学分相比,SRC比化学分接近BV(P<0.05)。文章讨论了RC法的优缺点。     

Amino acid contents of infant foods

The protein quality of three milk–cereal-based infant foods (paps) was evaluated by determining their amino acid contents and calculating the amino acid score. Proteins were subjected to acid hydrolysis, prior to which cysteine and methionine were oxidized with performic acid. Amino acids were determined by reverse-phase high-performance liquid chromatography with fluorescence detection with a prior derivatization with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate. Tryptophan was determined by reverse-phase high-performance liquid chromatography with ultraviolet detection after basic hydrolysis. Glutamic acid, proline and leucine were the most abundant amino acids, whereas tryptophan and cysteine had the lowest contents. Tryptophan was the limiting amino acid in the analyzed infant foods. A pap serving (250 ml) contributes significantly to fulfillment of the recommended dietary allowances of essential and semi-essential amino acids for infants (7–12 months old) and young children (1–3 years old).     

Protein Quality in Infant Formulas Marketed in Brazil: Assessments on Biodigestibility,Essential Amino Acid Content and Proteins of Biological Importance

Infant formulas, designed to provide similar nutritional composition and performance to human milk, are recommended when breastfeeding is not enough to provide for the nutritional needs of children under 12 months of age. In this context, the present study aimed to assess the protein quality and essential amino acid content of both starting (phase 1) and follow-up (phase 2) formulas from different manufacturers. The chemical amino acid score and protein digestibility corrected by the amino acid score were calculated. The determined protein contents in most formulas were above the maximum limit recommended by FAO and WHO guidelines and at odds with the protein contents declared in the label. All infant formulas contained lactoferrin (0.06 to 0.44 g·100 g⁻¹) and α-lactalbumin (0.02 to 1.34 g·100 g⁻¹) below recommended concentrations, whereas ĸ-casein (8.28 to 12.91 g·100 g⁻¹), α-casein (0.70 to 2.28 g·100 g⁻¹) and β-lactoglobulin (1.32 to 4.19 g·100 g⁻¹) were detected above recommended concentrations. Essential amino acid quantification indicated that threonine, leucine and phenylalanine were the most abundant amino acids found in the investigated infant formulas. In conclusion, infant formulas are still unconforming to nutritional breast milk quality and must be improved in order to follow current global health authority guidelines.     

我国八个人群血清氨基酸与血压的相关分析

以多因子回归及判别分析研究4地区、4民族八个人群共484人(男、40～59岁)的22种血清氨基酸水平与血压的关系,发现:1.住新疆同一地区的哈萨克、汉、维吾尔族的不同氨基酸水平可能反映其迥异的食物结构;而饮食相仿,住贵州同一山区汉、彝族组间的差别,提示除营养因子外、遗传代谢因子的影响。2.除门冬氨酸及(或)谷氨酸在居高寒山区的贵汉、彝组最高外,其他氨基酸水平在该区均较低,提示可能反映组织较慢的代谢更新率,与其血压、Quetelet指数及血清尿素水平较低也相一致。3.摄入动物蛋白量高的新疆(羊肉为主)或舟山(鱼为主)组人群,氨基酸水平均较高,难以将渔民中心脑血管病罹患率较低完全归因于摄入较多富含硫氨基酸的鱼肉。4.从血压回归方程提示缬、丰胱、丙、苏氨酸可能属升压性;亮、甲硫、苯丙、甘氨酸和谷胺酰胺可能属抗高血压性。     

Protein dietary reference intakes may be inadequate for vegetarians if low amounts of animal protein are consumed

Objective

The health benefits of vegetarian diets are well-recognized; however, long-term adherence to these diets may be associated with nutrient inadequacies, particularly vitamins B12 and D, calcium, iron, zinc, and protein. The dietary reference intakes (DRIs) expert panels recommended adjustments to the iron, zinc, and calcium DRIs for vegetarians to account for decreased bioavailability, but no adjustments were considered necessary for the protein DRI under the assumption that vegetarians consume about 50% of protein from animal (dairy/egg) sources. This study examined dietary protein sources in a convenience sample of 21 young adult vegetarian women who completed food logs on 4 consecutive days (3 weekdays and 1 weekend day).

Methods

The daily contribution percentages of protein consumed from cereals, legumes, nuts/seeds, fruits/vegetables, and dairy/egg were computed, and the protein digestibility corrected amino acid score of the daily diets was calculated.

Results

The calculated total dietary protein digestibility score for participants was 82 ± 1%, which differed significantly (P < 0.001) from the DRI reference score, 88%, and the 4-d average protein digestibility corrected amino acid score for the sample was 80 ± 2%, which also differed significantly (P < 0.001) from the DRI reference value, 100%. The analyses indicated that animal protein accounted for only 21% of dietary protein.

Conclusion

This research suggests that the protein DRI for vegetarians consuming less than the expected amounts of animal protein (45% to 50% of total protein) may need to be adjusted from 0.8 to about 1.0 g/kg to account for decreased protein bioavailability.     

克氏螯虾重要化学成分分析

对克氏螯虾微量元素和游离氨基酸的含量分析发现，其游离氨基酸的种类齐全、含量高，人体必需之重要微量元素锰、铁、锌、钴含量高，另外还富含硒和锗。提示螯虾可能具有一定的药用价值。     

不平衡氨基酸对卵巢癌多细胞球体生长影响

目的比较几种氨基酸溶液对卵巢癌多细胞球体（MCS）生长的影响。方法分别用含有平衡氨基酸、增量精氨酸、去蛋氨酸、去缬氨酸、复合氨基酸（增量精氨酸、去蛋氨酸、去缬氨酸）营养液的培养基培养卵巢癌MCS,观察并分析生长曲线、细胞周期,检测增殖细胞核抗原（PCNA）的表达。结果生长曲线可见平衡氨基酸组细胞生长速度明显高于其他各组,复合组细胞生长速度最慢,与其他组比较,差异有统计学意义（P〈0.05）。细胞周期可见平衡氨基酸组细胞多数处于S期,处于G0/G1期的细胞含量为（41.5±6.3）%,而复合组处于G0/G1期的为（77.6±4.7）%,与其他各组比较,差异有统计学意义（P〈0.05）。PCNA检测结果表明,复合组PCNA的转录水平低于其他各组。结论平衡氨基酸有利于卵巢癌MCS的生长;4种不平衡氨基酸对MCS的生长均有抑制作用,并能阻滞MCS细胞进入增殖期,其中复合氨基酸的作用最强。     

Protein content and amino acid scores of sweet potatoes in Papua New Guinea Highlands

Protein content and amino acid scores of sweet potatoes were determined in Papua New Guinea Highlands where sweet potatoes contributed approximately 50% of the total protein intake. Major cultivars of sweet potatoes in the Tari basin and the Asaro valley, 15 in total, were sampled and their nitrogen and amino acid contents were analyzed. Sweet potatoes in the Tari basin and the Asaro valley contained, respectively, 1.4% and 0.8% of protein in fresh weight basis. The concentration was 1.7 times higher in the former than in the latter (t‐test, p < .01). The first limiting amino acid was leucine in the samples from both areas and amino acid scores were 87 in the Tari samples and 85 in the Asaro samples, using values of FAO/WHO (1973). Protein content and amino acid scores of sweet potatoes in the Tari basin were higher than those previously reported in Papua New Guinea Highlands probably because of introduction of new cultivars in recent decades, and thus protein intake of the inhabitants may have been increased.     

大豆高支链氨基酸混合物营养价值的研究

大豆高支链氨基酸混合物是水解大豆蛋白质添加少量个别氨基酸制成的氨基酸混合物。其必需氨基酸含量占混合物的68.9％,支链氨基酸含量占42.9％。 动物喂养实验显示,此种氨基酸混合物能促进幼年大鼠生长,维持血红蛋白、血清总蛋白和白蛋白的正常含量,蛋白质功效比值(PER)、真消化率(TD)、生物价值(BV)、净蛋白质利用率(NPU)依次为2.78、94.0％、85.0％和80.0％。这些值均显著高于酪蛋白、略高于大豆平衡氨基酸,表明此种氨基酸混合物没有因支链氨基酸含量高而发生氨基酸拮抗作用,具有较高的营养价值。