蛋黄卵磷脂制备工艺及超临界CO_2脱蛋黄油实验研究

对用超临界CO_2萃取技术制备蛋黄卵磷脂的几种典型工艺进行了归纳、分析和比较。根据选择的工艺,对关键设备萃取器料筒进行了改进,通过正交试验,探讨了萃取压力、温度、时间、料筒层数等条件对蛋黄油脱除率的影响规律。     

脂质体载药性能与卵磷脂的关系

探讨了卵磷脂对脂质体载药性能的影响。用逆相蒸发法制备阿糖胞苷脂质体,通过测定脂质体的包封率、平均粒径和药物渗漏量,考察了蛋黄卵磷脂、大豆卵磷脂及猪脑卵磷脂对脂质体载药性能的影响。实验结果表明,在n(PC)∶n(CHOL)=1∶1的条件下,蛋黄卵磷脂脂质体的平均粒径为2.59μm,包封率为(17.02±0.21)%,在37℃经40 h温育后,平均粒径增加0.53μm,药物渗漏量为(0.18±0.01)mg/h。平均粒径和包封率均高于大豆卵磷脂脂质体及猪脑卵磷脂脂质体,平均粒径增加值低于大豆卵磷脂脂质体及猪脑卵磷脂脂质体,渗漏速度高于猪脑卵磷脂脂质体,但低于大豆卵磷脂脂质体。对比实验证明,蛋黄卵磷脂脂质体的载药性能较好。     

蛋黄卵磷脂细菌内毒素检查法研究

目的:建立蛋黄卵磷脂辅料的细菌内毒素检查法。方法:依据《中国药典》2015年版四部通则1 143细菌内毒素检查法,通过干扰试验,确定蛋黄卵磷脂最大无干扰浓度,并进行方法学验证。结果:蛋黄卵磷脂浓度稀释到5 mg/mL及乙醇浓度稀释到5%以下时对细菌内毒素检测无干扰。结论:建立的方法可用于蛋黄卵磷脂的细菌内毒素检查。     

超临界CO2萃取制备卵黄磷脂

采用超临界CO2萃取蛋黄粉中的蛋黄油及用食用酒精萃取卵磷脂，在较温和的工艺条件下制备卵黄磷脂。     

蛋黄卵磷脂中鞘磷脂的分离与结构鉴定

目的:通过柱层析与高效液相色谱方法对蛋黄卵磷脂中的鞘磷脂进行制备分离,采用ESI质谱、GC-MS、核磁共振方法对鞘磷脂进行结构鉴定。结论:从蛋黄卵磷脂中分离鉴定了5种鞘磷脂,分别是N-棕榈酰-3-磷酸胆碱酰鞘氨醇、N-亚油酰-3-磷酸胆碱酰鞘氨醇、N-油酰-3-磷酸胆碱酰鞘氨醇、N-硬脂酰-3-磷酸胆碱酰鞘氨醇以及N-花生四烯酰-3-磷酸胆碱酰鞘氨醇。蛋黄卵磷脂中鞘磷脂成分的全面分析为蛋黄卵磷脂的产品质量研究以及鞘磷脂在医药方面的药理研究与应用等方面提供物质结构参考。     

国内外卵磷脂生产及应用概况

一、概况卵磷脂又称大豆磷脂,天然存在于蛋黄、菜籽、大豆、向日葵籽、某些谷物中,另外在动物和人类大脑中也有少量存在。卵磷脂于19世纪首先在蛋黄中被发现。但实际具备商业用途的是大豆中所含的卵磷脂,在食品中应用已有60多年历史。大豆磷脂是由一些具有表面活性的物质组成的混合物。其主要成分是,磷脂酰胆碱(PC,也称卵磷脂)、磷脂酰乙醇胺(PE,也称脑磷脂)、磷脂酸(PA)和磷脂酰肌醇(PI)等。结构式如图1所示。     

蛋黄卵磷脂反相囊泡在乙醛酸修饰碳纤维上的构建

利用乙醛酸修饰碳纤维制备了蛋黄卵磷脂反相囊泡,并通过倒置生物光学显微镜实现反相囊泡的原位表征。乙醛酸和蛋黄卵磷脂分子之间的氢键作用对双分子层磷脂膜的构建和反相囊泡的形成起着至关重要的作用。在2~3 d的较长时间内,在乙醛酸修饰碳纤维上构建的反相囊泡结构能够较好地保持。     

卵磷脂的分离提取工艺研究

针对当前卵磷脂在各方面领域应用的广泛性,如何提高卵磷脂分离提取的纯度和得率,是当前研究的重点。结合以往乙醇分离提取的基础上,以蛋黄卵磷脂分离提取作为研究对象,分别研究了在不同有机溶剂、物料比、溶剂体积和冷冻温度等对分离的影响,并通过正交实验法得到最佳的提取工艺,即选择正乙烷作为有机溶剂,同时物料比为1∶4,溶剂体积比为1∶2.5,冷冻温度为-20℃,提取时间为30 min,提取次数为3次的情况下,经HPLC等方法的检测,得到的卵磷脂纯度可达到97.49%,得率为9.37%。由此说明本试验方法在卵磷脂提取方面具有一定的可行性。     

磷脂种类对于番茄红素磷脂复合物的溶解度的影响

目的采用不同种类的磷脂制备番茄红素磷脂复合物,并对不同种类的番茄红素磷脂复合物的理化性质进行比较。方法采用摩尔系数法确定番茄红素跟磷脂的最佳复合比,以复合率为指标采用正交试验确定最佳的制备过程,同时测定番茄红素和不同磷脂形成的磷脂复合物的溶解度和油水分配系数。结果采用蛋黄卵磷脂制备的番茄红素磷脂复合物的溶解性的改善程度较采用大豆磷脂制备的磷脂复合物更高,采用纯度较高的磷脂制备的番茄红素磷脂复合物具有更好的溶解性。结论番茄红素与蛋黄卵磷脂复合后更能够增加番茄红素的溶解性,高纯度的蛋黄卵磷脂增加番茄红素的溶解性更明显。     

乙醇提取鸭蛋黄卵磷脂的工艺研究

采用正交实验和单因素实验方法,考察了提取温度、乙醇浓度、提取时间、料液比对鸭蛋卵磷脂提取率的影响。结果表明：在提取温度30℃、乙醇浓度92%、提取时间60min且料液比为1：5的条件下,从鸭蛋黄中提取卵磷脂的得率达9.92%。     

Insect antifeedant properties of anthranoids from the genusVismia

Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.     

2007～2008年世界塑料工业进展

收集了2007年7月～2008年6月世界塑料工业的相关资料,介绍了2007～2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.     

2005～2006年国外塑料工业进展

收集了2005年7月～2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂（聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂）、工程塑料（聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚）、通用热固性树脂（酚醛、聚氨酯、不饱和树脂、环氧树脂）、特种工程塑料（聚苯硫醚、液晶聚合物、聚醚醚酮）的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。