爬山虎果实红色素的提取及其抗氧化能力的研究

研究了爬山虎果实红色素的提取方法、最佳提取条件及抗氧化能力，结果表明：最佳提取方法为水提法，最佳提取条件为温度50℃、时间2h、料液比1：4、溶剂为3％碱液。其红色素的抗氧化能力为53％。     

刺玫红色素微波辅助提取及其抗氧化性研究

采用微波法辅助提取刺玫红色素,在单因素的基础上进行正交实验,优化微波法提取刺玫红色素的最佳工艺条件。结果表明:乙醇浓度50%,微波功率500W,微波时间2min,提取温度60℃,料液比为1∶10 g/m L,此时刺玫红色素得率最高,达到2.03mg/g。体外抗氧化性研究结果显示,刺玫红色素具有一定的抗氧化能力,且随着溶液浓度的增大,其还原力增加,对羟基自由基(·OH)的清除能力、对超氧阴离子自由基(O~(2-)·)的清除能力均增加。     

微波辅助提取马齿苋红色素及稳定性研究

以马齿苋为原料,去离子水为提取剂,微波辅助条件下提取马齿苋红色素。对影响提取效果的因素如微波功率、提取时间、提取温度、液料比进行了研究。通过正交试验得到微波辅助提取马齿苋红色素的最佳条件。对马齿苋红色素耐热性、耐光性、耐紫外线照射稳定性、耐氧化还原性及耐酸碱性进行了研究,结果发现马齿苋红色素有较好的热稳定性、耐光性、抗氧化还原性; p H值和紫外光对其有一定的影响。马齿苋红色素在食品添加剂中具有一定的开发应用价值。     

月季花红色素提取条件的优化

本研究主要是优化月季花中红色素的提取工艺。研究乙醇浓度、水浴温度、料液比、超声波功率和超声波占空比5个因素对月季花红色素提取工艺的影响,通过响应面分析实验确定最佳提取工艺条件。得到最佳工艺条件为:乙醇浓度96. 1%、水浴温度80. 4℃、料液比1∶50、超声波功率463. 6W、超声波占空比为1/2。在最佳工艺条件下,月季花红色素提取率为12. 94%。     

超声波提取无花果皮红色素的研究

利用超声波技术提取无花果皮红色素,通过单因素和正交实验研究了红色素提取的最佳条件,结果表明,影响无花果皮红色素提取的主要因素是超声波功率,其次是超声波提取温度和超声波提取时间,再次是提取料液比。最佳提取条件为:超声波功率350 W,提取温度40℃,提取时间25 min,料液比1∶20(g/mL),收率为10.23%。     

超声波法提取蓝靛果中红色素的条件研究

通过正交设计实验的方法,探讨了超声波提取蓝靛果中红色素的工艺条件,确定了最佳提取条件为:酶解45℃,3 h,乙醇浓度60%,超声温度20℃,超声功率200 W,料液比1:20,时间50 min.在此条件下蓝靛果红色素的得率为9.28%.     

正交实验优化火龙果果皮红色素超声辅助醇提工艺

采用超声辅助乙醇浸提法提取火龙果果皮红色素,考察乙醇浓度、料液比、提取时间、提取温度对火龙果果皮红色素提取率的影响。结果表明,各因素影响主次顺序为料液比>乙醇浓度>提取时间>提取温度,最佳工艺条件为:提取剂为30%乙醇,料液比1∶50(g/m L),超声时间30 min,提取温度40℃。采用此最佳工艺条件提取火龙果果皮色素提取率为0.071%。     

正交实验优化火龙果果皮红色素超声辅助醇提工艺

采用超声辅助乙醇浸提法提取火龙果果皮红色素,考察乙醇浓度、料液比、提取时间、提取温度对火龙果果皮红色素提取率的影响。结果表明,各因素影响主次顺序为料液比乙醇浓度提取时间提取温度,最佳工艺条件为:提取剂为30%乙醇,料液比1∶50(g/m L),超声时间30 min,提取温度40℃。采用此最佳工艺条件提取火龙果果皮色素提取率为0.071%。     

超声波辅助提取紫背天葵红色素

以乙醇为溶剂,利用超声波法提取紫背天葵红色素。探讨了提取剂乙醇的浓度、提取温度、提取时间、料液比对紫背天葵红色素提取率的影响。结果表明,最佳提取工艺条件为:20%乙醇,50℃,浸提80 min,料液比为1∶13(g/m L),此时紫背天葵红色素提取率为10.04%。     

多指标正交实验优选红芪总黄酮提取工艺的研究

运用正交设计法,以总黄酮的得率及其抗氧化能力为评价指标,考察提取次数、溶剂浓度、提取时间、料液比4个因素对红芪总黄酮提取工艺的影响;紫外吸收法测定红芪总黄酮的含量,DPPH法测定总黄酮的抗氧化能力。结果表明,红芪总黄酮的最佳提取工艺为:药材加8倍量的65%乙醇,回流提取3次,每次40 min。在此条件下红芪总黄酮的提取率25.04%,抗氧化能力最佳,DPPH自由基清除率53.55%。     

Sapindaceae,cyanolipids, and bugs

Scentless plant bugs (Heteroptera: Rhopalidae) are so named because adults of the Serinethinae have vestigial metathoracic scent glands. Serinethines are seed predators of Sapindales, especially Sapindaceae that produce toxic cyanolipids. In two serinethine species whose ranges extend into the southern United States,Jadera haematoloma andJ. sanguinolenta, sequestration of host cyanolipids as glucosides renders these gregarious, aposematic insects unpalatable to a variety of predators. The blood glucoside profile and cyanogenesis ofJadera varies depending on the cyanolipid chemistry of hosts, and adults and larvae fed golden rain tree seeds (Koelreuteria paniculata) excrete the volatile lactone, 4-methyl-2(5H)-furanone, to which they are attracted.Jadera fed balloon vine seeds (Cardiospermum spp.) do not excrete the attractive lactone. Loss of the usual heteropteran defensive glands in serinethines may have coevolved with host specificity on toxic plants, and the orientation ofJadera to a volatile excretory product could be an adaptive response to save time.Mention of a commercial product does not consititute an endorsement by the USDA.     

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.     

2008～2009年世界塑料工业进展

收集了2008年7月～2009年6月世界塑料工业的相关资料,介绍了2008～2009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、环氧树脂、不饱和聚酯树脂)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。     

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.     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.