海藻酸钠/南极磷虾蛋白复合纤维的制备及性能研究

采用湿法纺丝技术制备了海藻酸钠/南极磷虾蛋白质(SA/AKP)复合纤维,研究了纤维力学性能的影响因素。结果表明:SA/AKP复合纤维的断裂强度随着蛋白质含量、凝固浴温度、凝固时间的增加而减小,随钙离子浓度的增加而先增大后减小;凝固剂钙离子与聚乙二醇溶液质量比为4∶1,制得SA/AKP复合纤维的断裂强度达1.21 cN/dtex,AKP的加入导致复合纤维的热失重增大。     

培哚普利对去势大鼠骨质疏松的影响

目的观察培哚普利对去势大鼠骨质疏松的影响。方法将大鼠随机分为5组,每组10只。经切除大鼠双侧卵巢建立骨质疏松动物模型(OVX组)后,低(LP组)、中(MP组)、高剂量培哚普利组(HP组)经灌胃分别按2、4、8 mg/(kg·d)给药(溶解于1 ml生理盐水),正常对照组(CON组)仅切除卵巢周围部分脂肪组织,CON与OVX组仅灌胃等体积(1 ml)的生理盐水,均仅给药1次。给药24周后经股动脉采血并处死大鼠,检测血清钙、磷及碱性磷酸酶(ALP)活性,取股骨检测骨密度及生物力学变化。结果与CON组比较,OVX组血清钙、磷、ALP活性及骨密度明显下降(P0.05)。与OVX组比较,MP及HP组大鼠的血清钙含量明显升高(P0.05);MP组大鼠的血清磷含量明显升高(P0.05);HP组大鼠的ALP活性明显升高(P0.05),MP及HP组大鼠的骨密度均明显升高(P0.05);MP组大鼠股骨的最大力学载荷明显升高(P0.05)。结论各剂量培哚普利对改善骨质疏松模型大鼠的骨密度及生物力学均有效果,以中剂量培哚普利改善效果最佳。     

胶原蛋白肽复合配方对去势大鼠骨质疏松的防治研究

目的评价胶原蛋白肽、植物雌激素染料木素和大豆甙元、柠檬酸钙联合防治去势大鼠骨质疏松的作用。方法 50只平均体重250g的三月龄SD雌性大鼠,随机分为5组,包括假手术组、去势对照组、雌激素组以及配方高剂量及低剂量组。给药12周,测定受试大鼠骨密度、Mi—cro—CT以及骨生物力学等。结果配方高剂量组与去势对照组相比股骨、股骨头以第四腰椎骨骨密度均有显著性的提高(P<0.05),并且比单独应用雌二醇效果更加明显。通过Micm—CT测得给药后受试大鼠的骨微结构相比去势对照组在骨容积率、骨小梁数量及骨小梁厚度上均有改善。给药组股骨的最大载荷与去势对照组相比有升高的趋势。结论高剂量的植物雌激素、胶原蛋白肽与柠檬酸钙联合应用能够改善卵巢去势大鼠的骨密度、骨微结构以及骨生物力学性质,对临床应用具有指导作用。     

南极臭氧层不断减少工业中的氟氯化碳成罪魁祸首

据11月3日俄罗斯媒体报道，联合国的科学家表示，南极周围的臭氧层正在不断地减少，这种情况主要是由于工业制造释放出的化学气体所造成的，他们要求世界环境公约立即行动起来采取保护措施。     

南极地区的污水处理与控制管理

南极是世界上唯一一块保存相对完整的大陆,随着各国44个永久考察站的建立和人类活动的增加,在南极大陆实施有效的环境管理与保护将变得愈加迫切.目前,污水排放是南极地区污染物进入环境的主要途径之一,本文在总结各国考察站污水处理实践的基础上,进一步探讨了南极地区污水处理的必要性、污水排放控制标准、污水处理难点、以及污水处理工艺选择等方面的环境技术与管理问题,以期对未来南极地区污水处置和管理提供借鉴.     

南极磷虾肽的功能活性与研究进展

南极磷虾是南极海域存储量丰富,以浮游动植物为食物的浮游动物。南极磷虾虾壳氟含量较高,虾肉含有丰富蛋白质,相对分子量在0.5～10000 Da之间的南极磷虾多肽具有降血压、抗疲劳、抗氧化性、抗菌性、降胆固醇等功能,现在已经被应用于药物和食品领域。本文综述了开发南极磷虾的目的、现存捕捞的技术难题及南极磷虾肽的生理活性,为开拓南极磷虾肽的应用范围提供参考。     

葡萄皮提取物与磷虾油对肥胖高脂血症大鼠血脂的影响

目的:通过试验研究了葡萄皮提取物与磷虾油对肥胖高脂血症大鼠血脂的影响,并对葡萄皮提取物与磷虾油配伍使用的安全性进行了考察。方法:以基础饲料饲喂大鼠,观察7天后,取尾血,测定各项血脂指标,根据血清总胆固醇(TC)水平,将动物随机分为正常对照组、高脂对照组、葡萄皮提取物组(26.7 mg/kg.bw)、磷虾油组(0.2 g/kg.bw)、葡萄皮磷虾油组(葡萄皮提取物13.5 mg/kg.bw、磷虾油0.1 g/kg.bw)共5组。正式实验开始后,除正常对照组继续喂普通饲料外其余各组动物换用高脂饲料。每日一次灌胃给予大鼠受试物溶液。高脂对照组灌胃给予相当体积的食用油,正常对照组灌胃等量蒸馏水。连续给予36d,并定期称量体重。于实验结束禁食16h取尾血测定各项血脂指标。还对葡萄皮提取物与磷虾油配伍使用的安全性进行了考察。结果:葡萄皮提取物组能显著降低高脂模型大鼠的TC、TG水平(P0.05),磷虾油组显著降低高脂模型大鼠的TC、TG水平(P0.05),升高HDL-C但不显著。二者配伍使用可显著降低TC、TG(P0.05,P0.01),显著升高HDL-C(P0.05)。葡萄皮磷虾油混合物MTD大于20.0 g/kg.bw,Ames试验,小鼠骨髓嗜多染红细胞微核试验及小鼠精子畸形试验结果均为阴性。结论:葡萄皮提取物与磷虾油具有降低血脂的作用,二者配合使用安全性高,对降低大鼠血脂具有协同增效作用。     

骨疏康颗粒对骨质疏松椎体压缩性骨折患者疗效指标影响

目的观察骨疏康颗粒对骨质疏松(OP)椎体压缩性骨折患者疗效指标影响。方法选择近期在我院骨科住院的OP椎体压缩性骨折患者75例,随机分2组:(1)治疗组37例,口服补肾中药骨疏康颗粒,1袋/d,连服6个月;(2)对照组38例,未服补肾中成药。全部患者均在治疗结束后进行疗效评定,指标包括日常生活活动能力(ADL)、CVRS疼痛评分和骨密度值。结果2组患者治疗前CVRS疼痛评分、骨密度值和ADL总分无明显区别(P均>0.05),治疗后2组患者CVRS疼痛评分、ADL总分和骨密度值均明显优于治疗前,同时治疗组上述各指标也显著优于对照组同期结果(P均<0.01～0.05)。结论骨疏康颗粒可显著改善骨质疏松(OP)脊柱压缩性骨折患者各种疗效指标。     

产抗生素南极海洋放线菌的筛选及培养条件优化

对32株南极海洋放线菌进行抑菌活性实验,筛选出3株具有一定抑菌活性的放线菌,分别命名为GD-F1、GD-F2和GD-F3,其中GD-F2的抑菌活性较高;探讨了碳源、氮源、pH值等条件对GD-F2产抗生素的影响,确定GD-F2产抗生素的最佳培养条件为：碳源为可溶性淀粉、氮源为大豆粉或酵母膏、用天然海水和蒸馏水各一半配制培养基、无机盐浓度为改良高氏一号培养基的一半、pH值为7．0,为南极海洋放线菌的机理研究和应用奠定了基础。     

橄榄多酚对卵巢切除大鼠骨密度和骨钙含量的影响

目的 利用卵巢切除大鼠模型,研究橄揽多酚对其骨密度和骨钙舍量的影响.方法 试验共设5组,假手术纽,高、中、低剂量组及溶剂对照组.观察包括生长发育/骨钙含量、骨密度等相关指标.结果 卵巢切除各组大鼠体重及增童显著大于假手术组各组之间右股骨干重差异无显著性在大鼠骨密度低下造模成功的前提下,试验末3个剂量组左股骨密度及中、高剂量组右股骨骨钙含量显著高于溶剂畸对照蛆.结论 橄榄多酚可显著增加卵巢切除大鼠股骨密度及骨钙含量.     

Stabilisation of trypsin-like enzymes from antarctic krill: Effect of polyols,polysaccharides and proteins

The stabilisation of trypsin-like enzymes purified from krill processing wastewater was studied using different proteins, polyols and polysaccharides. The effect of the different stabilisers was evaluated both in solution and in dry samples of the enzymes. In 40% (w/v) stabiliser solutions, the increase in half-life of enzyme activity followed the pattern: sorbitol > xylitol > glycerol > sucrose > maltodextrins, when polyols and polysaccharides were used. In 3% (w/v) protein solutions, the stabilising effect followed the order: hydrolysed collagen > bovine serum albumin > casein. The best result was obtained in a 50% (w/v) sorbitol solution where a 12-fold half-life increase was achieved. Different mechanisms of stabilisation were observed for these two groups of substances. In 50% (w/w) dry enzyme/stabiliser mixtures, the increase in half-life of krill trypsin-like enzymes was: maltodextrins > sucrose > sorbitol > mannitol > xylitol. Dry samples were also prepared by coprecipitation of the enzyme/stabiliser mixture with 95% ethanol, followed by oven drying of the coprecipitates. Under these conditions, the modified maltodextrin PSM 10 (Reppe-Glykos AB, Sweden) gave the best result with a 25-fold half-life increase. The relevance of this result for the industrial application of krill trypsin-like enzymes is discussed.     

Comprehensive characterization and evaluation of the process chain and products from Euphausia superba exocuticles to chitosan

Antarctic krill (Euphausia superba) is a source for compounds of high nutritive value. Within that process of extraction, exocuticles (shells) accumulate which are currently disposed. A valorization of the compounds of the exocuticle such as chitosan would be beneficial to avoid waste and to obtain a versatile polymer at the same time. In contrast to previous investigations focusing on chitosan production from whole krill, we applied and optimized process stages of the chitosan production from the exocuticles, performing a comprehensive analytical evaluation of the whole process, the side streams and the products for the first time. Degreasing was the first step resulting in a krill oil yield of 6.2% using ethanol. The fatty acid profile exhibited high contents of phospholipids (21.2%). Citric acid offered a demineralization efficiency of 93%. Deproteinization investigation revealed 2 M NaOH and 90°C for 2.5 h to be the best parameters, resulting in a deproteinization efficiency of 99.9% and a chitin content of 92.8%. The spectroscopic investigation indicated that the chitin has a crystallinity index of 76% and an acetylation degree of 88%. The deacetylation degrees of the resulting chitosans is determined to be 74%–88%, the molecular weight ranges from 102 to 126 kDa.     

Oxidative stability and non‐enzymatic browning reactions in Antarctic krill oil (Euphausia superba)

Antarctic krill oil has gained much consideration recently due to its rich content of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in the form of phospholipids and its powerful antioxidant known as astaxanthin. To secure these valuable bioactive nutrients in krill oil, a gentle and immediate on‐board processing of freshly captured krill is recommended. Compared to fish oil, krill oil has a more complex matrix, which leads to the formation of additional compounds from non‐enzymatic browning reactions. Lipid oxidation occurs through different pathways in krill oil and cannot be detected through classical analytical techniques such as determination of peroxide and anisidine value. Therefore selection of appropriate methods to evaluate the oxidative stability of krill oil is of high importance.

Figure 1 Open in figure viewer PowerPoint Development of lipid derived volatiles: (a & b) 1‐penten‐3‐ol and (c & d) 2‐pentylfuran in krill oil upon storage at two different incubation temperatures (20 and 40°C). The same pattern as (a & b) was obtained for (Z)‐2‐penten‐1‐ol and benzaldehyde, whereas the same pattern as (c & d) was obtained for 2‐heptanone and 2‐octanone. Values are mean ± SD (n = 3). Means sharing the same letter are not significantly different at 5% significant level. Reproduced from Lu et al. 2 with permission from Elsevier.     

Effect of a fluorine lateral moiety on the liquid crystallinity of wholly aromatic polyester-amides

We have identified the effect of a fluorine lateral moiety on the liquid crystallinity of wholly aromatic polyester-amides. The evolution of liquid crystal texture for two reaction systems, p-acetoxybenzoic acid (ABA)/acetoxy acetanilide (AAA)/3-fluorophthalic acid (FPA) and ABA/AAA/phthalic acid (PA), were examined and compared by in situ polymerizations under a polarizing microscope with a heating-stage. The fluorine lateral moiety was found to have an adverse effect on the liquid crystallinity. The system containing FPA needs higher critical ABA content (the rigid and straight monomer) to form liquid crystallinity than the system containing PA. In addition, the LC phase emerges faster in the ABA/AAA/PA system than in the ABA/AAA/FPA system during polymerizations. Amorphous phase reappears in the later stage of thin film polymerizations for both systems if ABA content is in a particular range. However, the ABA/AAA/FPA system has a greater amorphous area than the ABA/AAA/PA system.     

乳化体系对氟硅改性丙烯酸酯乳液性能的影响

采用不同的乳化体系来制备氟硅改性丙烯酸酯乳液,主要探讨了乳化体系对预乳化液稳定性、聚合稳定性、储存稳定性、转化率、粒径大小与分布以及吸水率的影响。结果表明,在所采用的乳化体系中,由聚氧乙烯-4-酚基醚硫酸铵盐(CO436)与1-丙烯基-α-羟基烷基磺酸钠(COPS-1)组成的复合乳液体系,可制得转化率高达98.85%的稳定乳液,乳液粒径呈单分散分布,乳胶膜的吸水率只有4.31%。