离子液体双水相提取菜籽粕蛋白及其相行为的研究

用浊度法测定并绘制了30℃下亲水性离子液体1-丁基-3-甲基咪唑氯盐([Bmim] Cl)+K2 HPO4+ H2O体系的三元相图,求得的离子液体在该双水相体系中的溶解度曲线方程分别为:w([Bmim]Cl,上相)=0.026 88 +0.914 32×exp(-w(K2HPO4,上相)/0.113 39),r上相=0.999 59w([Bmim]Cl,下相)=-0.044 11 +28.974 45 ×exp(-w(K2HPO4,下相)/0.028 26)+0.289 58×exp(-w(K2HPO4,下相)/0.678 55),r下相=0.991 24.建立了由[Bmim] Cl和K2HPO4形成的双水相体系提取菜籽粕蛋白质的新方法,考察了在该离子液体双水相体系中不同离子液体及其浓度、盐浓度以及蛋白质浓度、pH对菜籽蛋白提取率的影响;并通过L16(45)正交优化试验得到了离子液体双水相提取菜籽粕蛋白质的最佳工艺条件为:K2HPO4质量浓度为150 mg/mL、[Bmim] Cl质量浓度为350 mg/mL、菜籽蛋白质量浓度为70.0 mg/L、pH值为6.8.验证试验结果表明在此最佳条件下菜籽蛋白质的提取率达到99.1％,这显示了该分离体系对提取菜籽蛋白质的独特性,为进一步的放大试验或工业化规模生产奠定了一定的试验基础.     

响应面优化冷榨花生粕酶法制备多肽工艺的研究

运用了Min Run Equirelicated Res Ⅳ析因设计、爬陡坡试验以及中心复合响应面设计对碱性蛋白酶酶解冷榨花生粕蛋白制备活性多肽工艺进行了优化.析因设计结果和显著性分析发现,[E]和[S]为最重要因素(P＜0.01),酶解pH和酶解时间为重要因素(P＜0.05).在析因设计、爬陡坡试验设计结果基础上应用中心复合响应面设计对[E](X1)、[S](X2)和酶解时间(X3)进行了响应面优化分析.响应面优化结果表明,在[E] =4 300 U/g[S],[S]=10.0％,酶解时间为85 min最优条件下,酶解液多肽含量达到最高,为(0.209 ±0.005)％ (n =6),与模型预测值0.207 8％接近,偏差为5.77％.试验表明,酶促水解是制备活性多肽的有效方法.     

菜籽粕替代鱼粉对银鲫生长性能及饲料利用率的影响

为评估硬颗粒饲料和膨化饲料中菜籽粕替代鱼粉对银鲫生长及饲料利用率的影响,试验设计了4种等氮、等能的饲料,分别用菜籽粕替代饲料中0％(对照组)、25％、50％、75％的鱼粉,利用挤压膨化技术和环模制粒技术加工成4种膨化饲料和4种硬颗粒饲料,对银鲫进行为期50 d的饲养试验.结果显示:菜籽粕替代鱼粉饲喂银鲫后的生长性能及饲料利用率都呈现下降的趋势;相同饲料配方,饲喂膨化饲料的银鲫生长性能及饲料利用率优于饲喂硬颗粒饲料的银鲫.研究结果表明,菜籽粕替代银鲫饲料中适量的鱼粉是可行的,膨化饲料饲喂银鲫的效果优于硬颗粒饲料,利用膨化加工工艺可以显著提高银鲫饲料中菜籽粕对鱼粉替代量.     

水产饲料用寡肽豆粕制备工艺的研究

为了提高酶解豆粕在水产饲料中的加工质量,以寡肽得率为指标,在单因素试验的基础上采用正交试验优化Alcalase(碱性蛋白酶)和Flavourzyme(风味蛋白酶)同步酶解工艺条件.综合考虑成本和工艺要求等因素,确定双酶法制备寡肽豆粕的最优酶解工艺条件为:底物浓度80 g/L、酶活比(Alcalase:Flavourzyme) 2∶1、加酶量3 000 U/g、反应pH值8.0、反应温度61℃、酶解时间7.5h.最终产物寡肽得率为38.16％,DH值为22.69％,产品与α-淀粉具有较佳的亲和性,溶失率为(2.5±0.7)％.结果表明,以寡肽得率为指标,可以有效解决豆粕蛋白质水解进程中蛋白水解过度或不足问题,制备的寡肽豆粕其黏弹性和溶失率能够满足特种水产饲料加工需求.     

碱性蛋白酶水解脱脂玉米胚芽粕工艺的研究

研究了2709碱性蛋白酶水解脱脂玉米胚芽粕的最佳工艺.以脱脂玉米胚芽粕为原料,水解度为指标,在单因素试验的基础上,采用正交试验确定了脱脂玉米胚芽粕最佳水解工艺条件.得出最佳水解工艺条件为:底物浓度5％(占水的质量),加酶量5％(占底物的质量),水解温度45℃,水解pH 10.0,水解时间180 min.在此条件下,脱脂玉米胚芽粕的水解度为22.46％.     

高温菜籽粕醇洗制取饲用浓缩蛋白工艺条件的研究

研究以高温菜籽粕为原料,利用醇洗工艺制取优质饲用浓缩蛋白的最佳工艺条件.通过单因素及正交实验得到最佳工艺条件为:乙醇体积分数70％,固液比1∶7,醇洗温度50℃,醇洗次数3次,醇洗时间50 min.醇洗菜籽浓缩蛋白的蛋白质含量由高温菜籽粕的40.21％提高至61.02％,硫苷含量由45.21 μmol/g降至5.25 μmol/g,植酸含量由2.48％降至0.55％,单宁含量由1.92％降至0.36％,蛋白质必需氨基酸含量由13.50％提高至19.32％,KOH蛋白质溶解度由39.09％提高至53.18％,粗纤维含量由10.12％降低至9.68％.利用高温菜籽粕制取的醇洗菜籽浓缩蛋白是蛋白质含量高、低抗营养因子残留及必需氨基酸含量高、蛋白质溶解度高且适口性好的优质饲用浓缩蛋白.     

Effect of replacing solvent-extracted canola meal with high-oil traditional canola, high-oleic acid canola, or high-erucic acid rapeseed meals on rumen fermentation, digestibility, milk production, and milk fatty acid composition in lactating dairy cows

The objective of this experiment was to investigate the effects of replacing conventional, solvent-extracted canola meal (control; CTRL) with high oil content; conventional, mechanically extracted canola meal (CMEC); high-oleic, low polyunsaturated fatty acid (FA) canola meal (HOLL); and high-erucic acid, low-glucosinolate rapeseed meal (RPS) on rumen function, digestibility, milk production, and milk FA composition in lactating dairy cows. The experimental design was a replicated 4 × 4 Latin square with 8 lactating dairy cows. Four of the cows were ruminally cannulated. All oilseed meals were included at approximately 12 to 13% of dietary dry matter (DM). Crude protein and fat concentrations (% of DM) of the meals were 43 and 3.1%, 32.8 and 16.1%, 45.2 and 13.7%, and 34.3 and 17.9% for CTRL, CMEC, HOLL, and RPS, respectively. All diets were formulated to supply net energy of lactation in excess of requirements. The CMEC and RPS diets were predicted to be about 1% deficient in metabolizable protein. Relative to the CTRL, inclusion of high-oil seed meals in the diet lowered ruminal acetate concentration and the molar acetate:propionate ratio and decreased DM intake. Milk yield generally followed DM intake and was lower for CMEC and RPS than the CTRL. Treatments had no effect on milk composition, other than an increase in milk urea nitrogen concentration for HOLL. Fat-corrected milk (3.5%) feed efficiency was increased by HOLL and RPS compared with CTRL. Urinary urea nitrogen losses were increased by HOLL, which, as a consequence, increased the ammonia-emitting potential of manure. The ratio of milk N-to-N intake was greater for CMEC and RPS. Replacing solvent-extracted canola meal with the high-oil meal decreased milk fat 12:0, 14:0, 16:0, and total saturated FA content and enhanced cis-9 18:1 and total monounsaturated FA concentrations. Relative to the CTRL, canola increased total trans FA in milk, whereas inclusion of HOLL in the diet increased trans-11 18:1 and cis-9, trans-11 CLA content. The RPS increased milk fat cis-13 22:1 content from 0.07 to 2.33 g/100 g of FA. In conclusion, HOLL or RPS, which are likely to come from small-scale biodiesel plants where oil is cold pressed without hexane extraction, fed at levels at or above 12 to 13% of dietary DM may decrease feed intake and milk production, but can be used to alter milk FA composition in lactating dairy cows.     

用D-D中子发生器测量水泥生料中的元素含量

以D-D中子发生器作为中子源,用瞬发γ中子活化分析（PGNAA）检测水泥生料中主要元素Si、Al、Fe和Ca及其氧化物的百分含量。水泥生料中各元素被中子辐照而释放瞬发γ射线,通过测量γ射线的能量和强度,可对其进行定性和定量分析。测量结果与化学化验方法所得结果的相对偏差好于7.0％,在允许范围内,有较好的重复性。与化学化验方法相比,该方法不破坏样品、用时短、可同时测量多种元素、精确度和准确度高,能满足工业生产的要求。     

Removal of metals from landfill leachate by sorption to activated carbon, bone meal and iron fines

Sorption filters based on granular activated carbon, bone meal and iron fines were tested for their efficiency of removing metals from landfill leachate. Removal of Al, As, Ca, Cd, Co, Cr, Cu, Fe, Hg, Mg, Mn, Mo, Ni, Pb, Sr and Zn were studied in a laboratory scale setup. Activated carbon removed more than 90% of Co, Cr, Cu, Fe, Mn and Ni. Ca, Pb, Sr and Zn were removed but less efficiently. Bone meal removed over 80% of Cr, Fe, Hg, Mn and Sr and 20-80% of Al, Ca, Cu, Mo, Ni, Pb and Zn. Iron fines removed most metals (As, Ca, Co, Cr, Cu, Fe, Mg, Mn, Pb, Sr and Zn) to some extent but less efficiently. All materials released unwanted substances (metals, TOC or nutrients), highlighting the need to study the uptake and release of a large number of compounds, not only the target metals. To remove a wide range of metals using these materials two or more filter materials may need to be combined. Sorption mechanisms for all materials include ion exchange, sorption and precipitation. For iron fines oxidation of Fe(0) seems to be important for metal immobilisation.