透明质酸钙毒理学研究

目的研究透明质酸钙的毒理学特性。方法分别进行小鼠急性毒性实验和大鼠30 d喂养实验。结果样品对小鼠的急性毒性LD50大于5 g/kg;实验期内大鼠生长发育良好,血常规及血生化各项指标均在正常范围,病理组织学检查各脏器均未见有意义的病理改变。结论根据人体最大可能摄入量(100 mg/d)和急性毒性分级标准,透明质酸钙为无毒物质,对人体无毒害及副作用。     

Preparation and characterization of porous polyester fibres by salt leaching method

Porous polyester fibres with cotton-like dull characteristics were produced by salt leaching method. Polyester was synthesized in the presence of common salt. Fibres containing submicron size salt particles (0.5–1%) were prepared by melt spinning. The fibres were washed in hot water to remove the salt particles creating small craters of size 50–1000?nm. Partially oriented yarn (POY) and fully drawn yarn (FDY) were produced. POY samples were textured to produce polyester textured yarn containing salt particles. The influence of salt particles on polymer crystallization was investigated and found that the presence of salt significantly influences the rate of crystallization. The gloss values of porous FDYs were compared with standard semi-dull polyester yarns of same denier. The light scattering behaviour of the yarn has been enhanced due to porosity. This resulted in a fibre with better dullness characteristics. The light reflectance of porous yarn is lower in the 400–700?nm region compared to control FDY samples. The dyeability of the porous fibre was better than non-porous counterpart.     

嗜酸氧化亚铁硫杆菌浸取印刷线路板中铜的多点添加策略

考察了嗜酸氧化亚铁硫杆菌(Acidithiobacillus ferrooxidans)对废弃印刷电路板(PCBs)中铜回收的影响.由于PCBs添加时间和浓度显著影响菌体生长及铜浸取率,因而通过多点添加PCBs的策略促进铜浸取并减少对细胞生长的抑制.结果表明,PCBs添加量为18 g/L(4 g/L于48 h,6 g/L于96 h和8 g/L于144 h)时,经过240 h培养,铜浸取率达80%,说明该策略有效和可行.     

Borojo果酶解浓缩粉的毒理学安全性评价

本文通过动物实验,研究Borojo果酶解浓缩粉的食用安全性。采用急性毒性试验、小鼠骨髓微核试验、小鼠精子畸形试验及大鼠30天喂养试验对Borojoa果酶解浓缩粉进行评价。结果表明,雌雄小鼠经口急性毒性LD50〉21．5g/kg·bw,根据急陛毒性分级,受试物Borojo果酶解浓缩粉属无毒级物质;小鼠骨髓微核试验、小鼠精子畸形试验结果与对照组比较均无显著性差异;大鼠30d喂养试验表明各剂量组动物体重增重、食物利用率、脏体比、血液学检查及血液生化检查与对照组比较均无显著性差异;病理检查主要脏器未见明显中毒性病理改变,说明Borojo果酶解浓缩粉属于安全性食品。     

Hydrolysed collagen from Lates calcarifer skin: its acute toxicity and impact on cell proliferation and collagen production of fibroblasts

Acute toxicity in Wistar rat and the impact of hydrolysed collagen (HC) from seabass skin on in vitro cell proliferation and collagen production were studied using L929 fibroblasts. HC was rich in glycine (326 residue/1000 residue) and imino acids (196 residue/1000 residue). MALDI mass spectrum of HC showed several low MW peptides with MW range of 1050–1330 Da as the major components. Based on acute oral cytotoxicity test in Wistar rat, HC was considered as safe with LD₅₀ value higher than 5000 mg kg^?1 body. HC could promote L929 cell growth, especially when used in combination with vitamin C (VitC) at a ratio of 2:1. HC/VitC (2:1) mixture also exhibited the higher enhancement effect on collagen production of L929 cells, compared with HC or VitC alone. Thus, HC could be a promising candidate for biological applications, especially in combination with VitC, as nutraceuticals for skin care.     

黄花菜的保健功效及化学成分研究进展

黄花菜具有较高的营养价值,在中国传统中是药食两用的蔬菜。文中对近年来黄花菜的保健功效和化学成分的研究进行了综述,其保健功效主要包括抗氧化与抗癌、改善睡眠、杀虫、镇静、消炎、抗黄疸、抗抑郁等作用;化学成分主要为萜类、内酰胺类、蒽醌类、多酚类、精油、甾体皂苷、生物碱等;最后对其毒性进行了简要阐述。     

聚乙二醇修饰的蓖麻毒蛋白A链的免疫原性和在小鼠体内急性毒性研究

目的研究单甲氧聚乙二醇(mPEG)与蓖麻毒蛋白A链(RA)偶联后RA免疫原性和毒性的改变。方法从天然蓖麻籽中提取纯化的RA,经与含活性马来酰亚胺基团的mPEG反应偶联,得到纯化的mPEG偶联RA。用蛋白质印迹方法比较RA修饰前后的免疫原性,通过测定半数致死量(LD50)比较RA修饰前后的毒性。结果mPEG偶联RA后免疫原性和毒性均明显下降。偶联前RA链的LD50为2.37 mg.kg-1,经mPEG修饰后RA的LD50为6.15mg.kg-1。结论聚乙二醇能遮蔽RA,降低其免疫原性和毒性。     

Composition and insecticidal activity of essential oil from Pistacia lentiscus L. against Ectomyelois ceratoniae Zeller and Ephestia kuehniella Zeller (Lepidoptera: Pyralidae)

This study reports investigations on the chemical constituents and fumigant toxicity of Pistacia lentiscus L. (Anacardiaceae) essential oil against two major stored-date insects, carob moth Ectomyelois ceratoniae Zeller and Mediterranean flour moth Ephestia kuehniella Zeller. Results showed that P. lentiscus essential oil contained terpinene-4-ol (23.32%), α-terpineol (7.12%) and β-caryophyllene (22.62%) as major compounds. Fumigant toxicity tests showed that P. lentiscus oil was more toxic to E. kuehniella (LC₅₀ = 1.84 μl/l, LC₉₅ = 5.14 μl/l) than E. ceratoniae (LC₅₀ = 3.29 μl/l, LC₉₅ = 14.24 μl/l). The fecundity and hatching rate of both insects decreased with increases in concentration or exposure time to the oil. At 136 μl/l air, fecundities and hatching rates were respectively 35 eggs/female and 42.86% for E. ceratoniae and 78 eggs/female and 29.49% for E. kuehniella.     

金银花冲泡浸提的影响因素分析及状态参数优化

以提高水液中的营养成分和风味为目的，用保温杯冲泡，加盖水浸提金银花试验，探讨了冲泡浸提时间A、冲泡水温度B和溶媒浓度C等3个参数对液中的氨基酸浓度、可溶性固形物含量和pH值的影响。分析表明：冲泡水温度是阻碍金银花中的水溶性成分浸出的主要因素；冲泡浸提5min，水溶性成分大部分已浸出；增大溶媒浓度可提高冲泡浸提过程的推动力，加快水溶性成分浸出速度，但水液中的营养成分浓度或含量比例下降。通过均匀设计法优化的最佳冲泡浸提参数：溶媒浓度为15.5-18.7:1，冲泡水温度为77.5-95℃，浸提时间为2.5-18.1min。     

黄连花茶加工工艺及其抗氧化作用研究

以黄连的花薹为原料,研究了黄连花茶的加工工艺及其抗氧化活性。结果表明,黄连花薹经杀青、冷却后,干燥,包装制得的黄连花茶风味清香、复水性好。采用霍恩氏法,对花茶的急性毒性(LD50)进行测定,21.5g/kg·BW剂量下,实验动物未发现死亡及异常;大于15g/kg·BW剂量,属无毒。水浸出物对羟自由基(·OH)和过氧化氢(H2O2)均具有清除作用。