海水鱼与淡水鱼omega-3多不饱和脂肪酸含量的比较研究

研究杭州市场常见野生和饲养淡水鱼以及海水鱼omega-3多不饱和脂肪酸（PUFA）的成分及含量。将购买的四个品种淡水鱼（野生和饲养）和六种海水鱼鱼肉去骨切碎,用有机溶剂提取总脂肪,甲酯化后的脂肪酸用气相色谱分离分析。结果表明：总PUFA的含量为从海水刺鲳的37．2mg／100g到淡水野生桂鱼的1821．8mg／100g,其中omeg-3PUFA有C18：3n-3,C18：4n-3,C20：5n-3,C22：5n-3,C22：6n-3,总omega-3PUFA含量为从海水刺鲳的32．3mg／100g到淡水饲养黑鱼的1104．3mg／100g。不同品种鱼脂肪酸含量存在显著性差异（p〈0．001）。结论：野生和饲养淡水鱼以及海水鱼中omega-3PUFA的含量及成分均因品种不同而异,淡水鱼的摄入完全能满足人体日常所需的omega3多不饱和脂肪酸。     

气相色谱-质谱法分析六种鲈形目海水鱼脂肪含量和脂肪酸组成

分析六种鲈形目海水鱼脂肪酸组成,为海水鱼的生产加工提供理论依据。通过氯仿-甲醇法提取六种海水鱼肌肉的脂肪,运用气相色谱-质谱联用法对脂肪酸组成进行分析。六种鲈形目海水鱼肌肉粗脂肪含量为4.40%~8.72%,其中黄鳍鲷含量最高,总共检测出21种脂肪酸,包括6种饱和脂肪酸(saturated fatty acids,SFA)和15种不饱和脂肪酸(5种单不饱和脂肪酸(monounsaturated fatty acids,MUFA)和10种多不饱和脂肪酸(polyunsaturated fatty acids,PUFA)),粗脂肪和脂肪酸总体含量均有显著差异(P<0.05),其中SFA含量为26.63%~33.97%,MUFA含量为23.07%~29.13%,PUFA含量为41.06%~44.35%。6种鲈形目海水鱼EPA和DHA占脂肪酸总量为21.17%~35.73%,除了黄鳍鲷,其他5种海水鱼占比均在30%以上,其中马拉巴笛鲷中占比最高,为35.73%。六种鲈形目海水鱼中MUFA/SFA总体有显著差异(P<0.05),其中黒鲷最高(1.43),马拉巴笛鲷次之(1.36)。6种鲈形目海水鱼中多不饱和脂肪酸比较丰富,其中马拉巴笛鲷的EPA+DHA含量较高,按照人们对于必需脂肪酸的需求,马拉巴笛鲷的营养价值最高。     

新鲜海鳗呈味物质及其挥发性风味物质分析

对新鲜海鳗肌肉的一般营养成分、脂肪酸组成、游离氨基酸、ATP(腺苷三磷酸)及其关联物、挥发性风味成分进行测定,以分析海鳗的营养及风味特性。结果表明：海鳗肌肉中不饱和脂肪酸占总脂肪酸含量的65.41%,其中多不饱和脂肪酸占23.63%,DHA(二十二碳六烯酸)和EPA(二十碳五烯酸)含量较高;甘氨酸、赖氨酸和丙氨酸为主要的游离氨基酸,含量分别为2.41、1.50g/kg 和0.89g/kg;IMP(肌苷酸)对海鳗的鲜味有很大贡献,在新鲜海鳗肉中的含量高达7.15μmol/g;海鳗肌肉挥发性风味成分中含量最高的是烷烃类化合物,对鳗肉嗅感起作用的主要是醛类、酮类和含硫化合物。     

北部湾海区几种常见牡蛎基础营养及脂肪酸成分比较分析

目的 比较分析北部湾海区常见的熊本牡蛎、香港牡蛎和近江牡蛎鲜品的基础营养成分及脂肪酸组成。方法 以北部湾海区熊本牡蛎、香港牡蛎和近江牡蛎为实验样品, 测定其水分、粗蛋白、粗脂肪和灰分的含量, 并用气相色谱-质谱联用法(gas chromatography-mass spectrometry, GC-MS)测定脂肪酸组成及含量。 结果 香港牡蛎的水分含量(89.44 g/100 g)、近江牡蛎粗脂肪含量(1.09 g/100 g)和灰分含量(1.77 g/100 g)均显著高于另两种牡蛎(P<0.05), 香港牡蛎粗蛋白含量(4.59 g/100 g)显著低于另两种牡蛎(P>0.05)。熊本牡蛎和近江牡蛎含有33种脂肪酸, 而香港牡蛎为34种, 其中多不饱和脂肪酸(polyunsaturated fatty acid, PUFA)含量占41.02%~50.79%; 3种牡蛎中二十碳五烯酸(eicosapentaenoic acid, EPA)、二十二碳六烯酸(docosahexoenoic acid, DHA)的含量占脂肪酸总量的27.13%~38.65%, 近江牡蛎(27.13%)显著低于另两种牡蛎(P<0.05)。结论 北部湾海区熊本牡蛎、香港牡蛎和近江牡蛎脂肪酸种类丰富, 与饱和脂肪酸及单不饱和脂肪酸含量所占脂肪酸总量相比, PUFA占比最高, 且以DHA和EPA为主, 具有优良的开发潜力。     

四种河鲀鱼皮和鱼肉的营养成分分析与评价

对菊黄东方鲀Fugu. flavidus、双斑东方鲀Fugu. bimaculatus、红鳍东方鲀Fugu. rubripes和暗纹东方鲀Fugu. obscurus鱼皮和鱼肉的营养成分进行分析和评价。结果显示,4种河鲀具有较高的蛋白质含量、较低的脂肪含量,鱼肉的蛋白质质量较好,而鱼皮含有较高的微量元素,更具鲜甜风味。其中,鱼皮的粗蛋白质含量(20.17%～37.61%)高于鱼肉(18.13%～23.27%),菊黄东方鲀最高,但是鱼肉的∑EAA/∑TAA(39.01%～43.11%)、∑EAA/∑NEAA(65.26%～71.57%)和EAAI(0.75～1.00)高于鱼皮(16.61%～20.49%、19.78%～25.70%和0.25～0.51),且符合FAO/WHO标准,双斑东方鲀的含量最高;鱼皮(0.20%～0.40%)和鱼肉(0.21%～0.4%)的粗脂肪含量均较低,鱼肉的∑FA(0.28%～0.39%)、w-3 PUFA(0.05%～0.15%)和w-6 PUFA(0.01%～0.09%)含量高于鱼皮(0.15%～0.24%、0.02%～0.03%和0.01%～0.04%),其中红鳍东方鲀的w-3 PUFA含量最高;菊黄东方鲀鱼皮含有较高的Ca含量(1737.47 mg/100 g),双斑东方鲀鱼肉含有较高的K含量(439.00 mg/100 g),红鳍东方鲀含有最高的Zn含量(0.90 mg/100 g和8.93 mg/100 g)。研究表明,4种河鲀均是高蛋白低脂肪的经济鱼类,氨基酸、脂肪酸和矿物质元素丰富、比例均衡、营养价值较高。     

林蛙油营养成分综合分析

本文对林蛙油中水分、灰分、脂肪酸、蛋白质、氨基酸、胆固醇等成分进行了系统研究,旨在为林蛙油的开发利用提供理论基础。结果表明,林蛙油富含粗脂肪和蛋白质;林蛙油中检测到12种脂肪酸,不饱和脂肪酸含量高达66.13%,单不饱和脂肪酸(MUFA)含量达38.18%,饱和脂肪酸(SFA)含量为34.16%,多不饱和脂肪酸(PUFA)含量为27.95%;致动脉硬化指数(AI)和凝血指数(TI)分别为1.40和0.70;氨基酸含量为11.49 g/100 g,8种必需氨基酸含量达51.61%;胆固醇含量为451.52 mg/100 g。综上所述,林蛙油脂溶性成分丰富,是一种健康的功效性产品。     

金鲳鱼不同组织脂肪酸组成比较

为提高金鲳鱼加工中副产物的利用率,本实验采用氯仿-甲醇法提取金鲳鱼5个组织部位中的脂质,采用GC-FID法测定各组织脂肪酸组成。脂质含量由高到低依次为:内脏(27.12±7.96) g/100 g>鱼身骨(16.04±3.35) g/100 g≈鱼头(15.88±3.09) g/100 g>鱼皮(11.93±5.72) g/100 g>鱼身肉(5.09±2.13) g/100 g。5个组织脂肪酸组成基本相同,富含油酸(24.31%~25.84%)、棕榈酸(23.16%~25.00%)和亚油酸(19.04%~19.76%)。饱和脂肪酸(SFA)在内脏(35.32%±2.17%)中含量最高,显著高于其它组织(p<0.05);单不饱和脂肪酸(MUFA)在鱼身骨(34.27%±1.28%)、鱼头(34.56%±1.32%)及鱼身肉(34.34%±1.57%)中含量显著高于内脏(32.68%±1.64%)和鱼皮(33.22%±1.23%)(p<0.05);多不饱和脂肪酸(PUFA)在5个组织间含量无显著差异;n-3PUFA和EPA+DHA在鱼皮(10.34%±1.76%和6.04%±1.53%)中含量最高,显著高于其它组织(p<0.05)。内脏中SFA(35.32%±2.17%) > MUFA(32.68%±1.64%) > PUFA(31.09%±3.18%);鱼身骨、鱼头及鱼身肉中MUFA > SFA ≈ PUFA;鱼皮中SFA(33.70%±2.22%) ≥ MUFA(33.22%±1.23%) ≥ PUFA(32.07%±3.23%)。因此,金鲳鱼组织脂质营养丰富,颇具开发利用价值。     

功能性调和油的研制

依据我国人民饮食中猪脂摄入量22.6g/人·日和25g色拉油/人·日(国家统计局2002年统计显示:猪肉消费量91g/人·日,猪肉平均脂肪含量24.8%),选用大豆油、米糠油、菜籽油、棉籽油、葵花油、亚麻油、椰子油等十几种色拉油、以及浓香花生油和芝麻香油,根据气相色谱及高压液相色谱分析测定的油脂脂肪酸组成、VE含量,以及市售油脂的价格因素等建立了功能性调和油的线性规划问题的数学模型,用Mathematica4.0求解各油脂配比,根据求解与调和工艺制成脂肪酸配比达到饱和脂肪酸(SFA):单不饱和脂肪酸(MUFA):多不饱和脂肪酸(PUFA)配比为3∶4∶3(n-6∶n-3=4～6∶1)、含0.8mg维生素E/1g不饱和脂肪酸的功能性调和油。     

牦牛肾脂氧化初期脂肪酸动态变化研究

以牦牛肾周脂为研究对象,研究了其在15±1℃下储藏期脂肪酸的动态变化。结果表明:牦牛肾脂肪氧化初期发生于储藏期第0～25d(15±1℃),在此期间,饱和脂肪酸(SFA)含量由49.68%提高至55.96%,多不饱和脂肪酸(PUFA)含量和单不饱和脂肪酸(MUFA)分别由10.73%和37.85%下降至6.95%和28.22%。第0～20d,n-6/n-3PUFA的比率低于4,但在第25d达到4.46,并且MUFA/SFA较PUFA/SFA下降幅度高11.24%。此外,除共轭亚油酸(CLA)和油酸(LA)外,功能性脂肪酸(ARA,EPA,DHA)在10d后下降显著(p<0.05)。     

鄱阳湖10种淡水鱼脂肪酸的特性研究

为了探讨中国最大淡水湖鱼类脂肪酸的特点,采用气相色谱法对鄱阳湖10种野生淡水鱼类脂肪酸的组成和含量进行分析.结果发现,鄱阳湖10种淡水鱼中最丰富的脂肪酸是油酸(C18:1n9);鱼中多不饱和脂肪酸(PUFA)的含量随鱼类品种的不同有较大的差别,大眼鳜肌肉的二十二碳六烯酸(DHA)含量最高达14.19%;赤眼鳟的花生四烯酸(AA)含量最高,肌肉和鱼头分别达13.53%和12.07%;麦穗鱼的二十碳五烯酸(EPA)含量最高,肌肉和鱼头分别为7.60%和7.92%.所分析的鱼PUFA/饱和脂肪酸(SFA)的值都在0.5以上,n6 PUFA/n3 PUFA为0.45～1.19;此外,鱼中还含有一定量的奇数碳脂肪酸,银鲴鱼头中含量最高达6.84%.结果表明鄱阳湖水域中,鱼PUFA有明显的特征,部分鱼中DHA和EPA的含量显著高于一般的淡水鱼,甚至与海鱼相近.PUFA和n3 PUFA含量与鱼的生活习性有较大关系,以藻类为主食的鱼>以鱼虾为主食的鱼>以软体动物和水生昆虫为主食的鱼.     

湛江对虾副产物酶解制备抗氧化肽

以湛江对虾加工副产物虾头为研究对象,研究虾头的酶解条件和酶解产物的抗氧化活性,选用木瓜蛋白酶和胃蛋白酶分别对虾头酶解,制备高活性的抗氧化肽。在单因素的基础上,以清除DPPH自由基为指标,研究时间、温度、加酶量、pH对酶解产物抗氧化活性的影响。结果表明,与木瓜蛋白酶相比,胃蛋白酶酶解产物的抗氧化效果更好;通过正交试验,确定胃蛋白酶酶解产物的最佳条件为温度32℃、酶解时间1 h、pH 1、加酶量为1.33×10-5kat/g(以底物计),在此条件下酶解产物的抗氧化活性最高,对DPPH自由基清除率为89.12%。     

黑龙江高粱水提物中原花青素的结构表征

旨在对水提取黑龙江产高粱中的原花青素进行鉴定。通过正交实验优化提取工艺,大孔树脂柱层析纯化,并采用UV、IR、MS进行鉴定。结果表明用水作提取剂提取高粱外种皮中原花青素的最佳工艺条件:时间60min,温度90℃,料液比1∶20,pH值为5,大孔树脂分离纯化得到产品纯度达98.48%,纯化产物为聚合度小于6的低聚体原花青素。     

利用动物血发酵酱油

各种屠宰动物血是一种资源量很大的蛋白质,营养丰富,在食品开发方面,大规模利用动物血的报道不多,本文报道了一种利用动物血制作酱油的新工艺。利用动物血制作酱油的主要优点是质量高、成本低。采用本文报道的工艺制作的血酱油成功地消除了血的腥臭气,并且酱香浓郁,产品的各项主要指标均达到了优质酱油的水平,氨基氮含量达到1.1g/100mL,为屠宰动物血的大规模利用提供了一条新的途径。利用酵母和乳酸菌进行后处理,对血酱油的质量提高具有重要意义,并对增香处理的工艺条件进行了初步探索。     

Properties of gum exudates from selected Albizia species from Tanzania

Gum samples from three selected Albizia species from Tanzania have been analysed and their commercial potential determined by comparing their properties with those of Albizia zygia and Acacia gums. The properties of the gum exudates from Albizia amara, Albizia pertesiana and Albizia harveyi have been found to be similar to those of A. zygia gum except that their aqueous solutions possess slightly lower viscosity and higher levels of tannin. The Albizia gums were much less soluble in water than Acacia gums; however, their methoxyl contents and acid equivalent weights (AEW) were similar to those of some Acacia gums.     

Isolation and Properties of Starch from Wild Yam from Zimbabwe

Wild Yam (Dioscorea dumetorum) was collected during the wet as well as dry season in the bush of Zimbabwe. Starch from its tubers was isolated in behavioral conditions and properties were determined such as size of granules, content of water, amylose, phosphorus, proteins and lipids, characteristics of gelation of its gels and thermal properties (TG, DTG, DTA).     

Formation of Anthocyanins from Cells Cultured from Different Parts of Strawberry Plants

Anthocyanin formation and structural identification were investigated in the cultured strawberry, Fragaria unannssa cv Shikinari. Friable callus tissues were obtained from apical meristems, leafs, and petioles grown on LS agar medium with 2,4-dichlorophenoxyacetic acid and benzyladenine. Using these calli, effects of auxins and cell inoculum size on pigment production were studied in suspension culture. Anthocyanin was produced under 8000 lux after preculture for 3 wk under 800 Iux in suspension culture. The main extracted pigment was identified as a peonidin-3-glucoside and the second major pigment was a cyanidin-3-glucoside by FABMS and NMR. Anthocyanin production was stimulated by 2,4-dichlorophenoxyacetic acid and its yield was about three times that of indole-3-acetic acid. An inoculum rate of 2g (fresh weight)/100 mL LS medium resulted in highest pigment production. The callus derived from the leaf was much higher in anthocyanin production than the others tissues of strawberry.     

Value added products from fermentation of sugars derived from agro-food residues

BackgroundGlobally, significant amounts of agro-food residues are generated, most of which are burned as waste disposal. Given the abundance of this biomass, it can be used as raw material for the production of biofuels and valuable chemicals through biochemical conversion. Research in this field has gained importance given concerns regarding limitation of fossil resources, environmental problems and sustainability and preference towards natural, biodegradable and environmentally friendly products. Furthermore, the accessibility of alternative substrate sources for fermentative production of these high-value products has been one of the primary goals of industrial biotechnology research in the past two decades.Scope and approachThe present review is focused in the production of high value products through microbial fermentation of sugars from agro-food residues. Research in this field is interesting due to concerns regarding limitation of fossil resources. On the one hand, for the production of these bioproducts it is important the accessibility of alternative substrate and, on the other hand, the selection of the right microorganism to obtain the desired product. For this reason, the novelty of the present work is that details all different bioproducts which can be obtained through fermentation of sugars derived from agro-food residues, describing raw materials, pretreatments, mode of operation, conditions and microorganisms used, together with the production yields.Key findings and conclusionsThe use of renewable and environmentally sustainable agro-food residues as raw material for the production of bio-based products has gained interest recently. For this purpose, the application of a suitable pretreatment to improve biomass digestibility and the optimization of biomass hydrolysis for the production of fermentable sugars is crucial to make bio-based products competitive with petroleum-based ones. The combination of pretreatments together with the employment of microorganisms tolerant to inhibitors generated during the pretreatment or able to ferment pentose sugars in hydrolysates have turned out to be interesting approaches. Regarding hydrolysis and fermentation, SHF and SSF are the predominant strategies, although CBP and SSCF have gained recognition recently. The final bioproduct cost depends on the productivity, yield per quantity of substrate, cost of raw material and the recovery method. In this way, for the commercialization of these bioproducts, some technical challenges are still needed, including the reduction of the pretreatments and enzymes costs, the design of strains with tailored capabilities, downstream processes optimization, waste treatment, etc.     

四个不同产地淫羊藿热裂解产物对比分析

采用裂解色谱法研究比较4个产地淫羊藿的裂解组分。结果表明:4个产地的淫羊藿裂解产物分别为云南6 8个、吉林4 8个、辽宁5 1个、四川5 6个,主要为酚类、酮类、醛类、烯烃、芳烃、萜类、杂环类化合物;主要裂解产物为苯酚(相对含量在5%～8%之间),其他为环戊烯酮类、苯酚衍生物、2,3-二氢-苯并呋喃等;不同地域的同种药材其裂解产物分布基本相同,但各组分的含量差异却很大;高效液相色谱法测定不同地域淫羊藿中淫羊藿甙含量表明:云南为5.49%、四川为12.85%、辽宁为1.95%、吉林为2.82%,差异比较大。     

Exfoliation of Helicobacter pylori from gastric mucin by glycopolypeptides from buttermilk

In the human stomach, Helicobacter pylori, an ulcer pathogenic bacterium, colonizes the gastric mucosal layer primarily. The ability of glycopolypeptides (GPP) prepared from buttermilk to exfoliate H. pylori bound to gastric mucin was investigated. The GPP were prepared from buttermilk by digestion with trypsin, papain, pancreatin, bromelain, or pepsin. Helicobacter pylori ATCC 43504T and 43579 adhered more strongly to all of the GPP tested than to whole buttermilk, the soluble fraction of buttermilk, gastric mucin prepared from mouse stomach, or commercial pig gastric mucin. The GPP digested with trypsin, papain, or pancreatin were significantly more adherent. When the GPP concentration was 10 mg/mL, bound H. pylori ATCC 43504T, 43579, and 5 clinical isolates were exfoliated markedly from immobilized porcine gastric mucin following treatment with GPP digested with trypsin or pancreatin. This ability of GPP did not correlate with sialic acid content, indicating that sialic acid content is not important in the exfoliation of this microorganism. Such an ability may depend on the structure or number of sugar chains, or the position of sialic acid. We conclude that GPP promote the exfoliation of H. pylori bound to gastric mucin and prevent the de novo adherence of this microorganism. As such, GPP are a promising food material for preventing H. pylori infection.     

罗非鱼胶原肽制备中钙回收工艺的研究

对比柠檬酸和乳酸对罗非鱼骨与鱼鳞中钙的溶解能力,选择乳酸作为罗非鱼骨、鳞胶原肽制备过程中脱钙的酸化剂.当采用20%乳酸,料液比1:9、35℃下酸解骨鳞原料10h时,骨磷钙的溶出率为88.12%.乳酸钙上清液在0.1MPa下真空浓缩,浓缩比达到6.2:1-6.7:1时,将浓缩液循序降温至5℃并保持3h,使乳酸钙结晶析出.经回液分离、精制、干燥后,得到纯度为98.3%的乳酸钙晶体.