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1.
Plant-derived products and their extracted compounds have been used in folk medicine since early times. Zimbro or common juniper (Juniperus communis) is traditionally used to treat renal suppression, acute and chronic cystitis, bladder catarrh, albuminuria, leucorrhea, and amenorrhea. These uses are mainly attributed to its bioactive composition, which is very rich in phenolics, terpenoids, organic acids, alkaloids, and volatile compounds. In the last few years, several studies have analyzed the huge potential of this evergreen shrub, describing a wide range of activities with relevance in different biomedical discipline areas, namely antimicrobial potential against human pathogens and foodborne microorganisms, notorious antioxidant and anti-inflammatory activities, antidiabetic, antihypercholesterolemic and antihyperlipidemic effects, and neuroprotective action, as well as antiproliferative ability against cancer cells and the ability to activate inductive hepato-, renal- and gastroprotective mechanisms. Owing to these promising activities, extracts and bioactive compounds of juniper could be useful for the development of new pharmacological applications in the treatment of several acute and chronic human diseases.  相似文献   
2.
马红  关成宏  陶波 《中国油料》2010,(1):136-138
应用盆栽的方法,比较了不同叶龄鸭跖草对咪唑乙烟酸的耐药性。结果表明,随着叶龄的增大,施药后鸭跖草叶中丙二醛(MDA)含量变化量下降,而叶绿素含量、光合速率及气孔导度恢复越快。由于3叶期开始鸭跖草耐药性迅速增强,因此,3叶以前是鸭跖草施药的最佳时期。  相似文献   
3.
Aliphatic polycarbonates are one important kind of biodegradable polymers and have been commonly used as integral components of engineered tissues, medical devices and drug delivery systems. As far as the biomedical application is concerned, traditional aliphatic polycarbonates usually suffer from the strong hydrophobicity, deficient functionality, and insufficient compatibility with cell/organs. Consequently, the application is quite limited in scope. Due to the imparted appealing properties, aliphatic polycarbonates bearing specifically designed functional/reactive groups attract great interest from researchers in the recent years. The present review outlines the development up to date concerning the design and biomedical application of functional aliphatic polycarbonates, with an emphasis on their ring-opening (co)polymerization preparation.  相似文献   
4.
Acyl-CoA:lysophosphatidylcholine acyltransferase (LPCAT, EC 2.3.1.23) catalyzes acylation of lysophosphatidylcholine (lysoPtdCho) to produce phosphatidylcholine (PtdCho), the main phospholipid in cellular membranes. This reaction is a key component of the acyl-editing process, involving recycling of the fatty acids (FA) mainly at the sn-2 position of PtdCho. Growing evidences indicate that the LPCAT reaction controls the direct entry of newly synthesized FA into PtdCho and, at least in some plant species, it has an important impact on the synthesis and composition of triacylglycerols. Here we describe the molecular characterization of the single LPCAT gene found in the genome of Ricinus communis (RcLPCAT) that is homologous to LPCAT genes of the MBOAT family previously described in Arabidopsis and Brassica. RcLPCAT is ubiquitously expressed in all organs of the castor plant. Biochemical properties have been studied by heterologous expression of RcLPCAT in the ale1 yeast mutant, defective in lysophospholipid acyltransferase activity. RcLPCAT preferentially acylates lysoPtdCho against other lysophospholipids (lysoPL) and does not discriminates the acyl chain in the acceptor, displaying a strong activity with alkyl lysoPL. Regarding the acyl-CoA donor, RcLPCAT uses monounsaturated fatty acid thioesters, such as oleoyl-CoA (18:1-CoA), as preferred donors, while it has a low activity with saturated fatty acids and shows a poor utilization of ricinoleoyl-CoA (18:1-OH-CoA). These characteristics are discussed in terms of a possible role of RcLPCAT in regulating the entry of FA into PtdCho and the exclusion from the membranes of the hydroxylated FA.  相似文献   
5.
蓖麻毒蛋白的研究与应用   总被引:3,自引:0,他引:3  
孙媚华  陈迁  宋光泉  刘勇  杜建军 《广东化工》2009,36(9):144-145,162
蓖麻毒蛋白(Ricin)是一种核糖体失活蛋白,由A、B两个肽链以二硫键共价相连接,其A链在B链的协助下,容易穿过细胞膜,破坏核蛋白体60S亚单位,抑制蛋白质的合成,导致细胞死亡。Ricin几乎对所有真核细胞具有很强的毒害作用,被认为是一种新型的很有希望的抗癌药物以及具有极大潜力的生物农药。Ricin能抑制昆虫的蛋白质合成,而植物自身能免受毒害,因此利用Ricin开发生物农药具有广阔前景。文章筒述了Ricin的分离纯化方法、结构及性质,毒性作用机理,及其在医学,生物农药,军事等方面的应用。  相似文献   
6.
熊素英  朱丽霞  张娜 《食品科学》2008,29(2):497-499
以纯巴旦杏乳为原料生产酸奶,对菌种的适应性、复配乳化稳定剂的选用及发酵条件等进行了研究,确定最适稳定条件为:羧甲基纤维素钠、蔗糖酯0.06%、单甘酯0.06%、果胶0.1%;乳糖3%有利于菌种的生长,提高发酵品的品质;最适发酵条件为:发酵剂3.5%、蔗糖7%、杏乳浓度9%,发酵时间5h,终点酸度90~100°T.产品组织状态及风味都较好.  相似文献   
7.
Lipophilic bioactive compounds in oils recovered from the seeds of eight pear (Pyrus communis L.) cultivars were studied. Oil yield in pear seeds ranged between 16.3 and 31.5 % (w/w) dw. The main fatty acids were palmitic acid (6.13–8.52 %), oleic acid (27.39–38.17 %) and linoleic acid (50.73–63.78 %), all three representing 96–99 % of the total detected fatty acids. The range of total tocochromanols was between 120.5 and 216.1 mg/100 g of oil. Independent of the cultivar, the γ‐tocopherol was the main tocochromanol and constituted approximately 88 %. The contents of the carotenoids and squalene were between 0.69–2.99 and 25.5–40.8 mg/100 g of oil, respectively. The β‐sitosterol constituted 83.4–87.6 % of total sterols contents, which ranged between 276.4 and 600.1 mg/100 g of oil. Three significant correlations were found between oil yield and total contents of sterols (r = ?0.893), tocochromanols (r = ?0.955) and carotenoids (r = ?0.685) in pear seed oils.  相似文献   
8.
To facilitate the analysis of castor (Ricinus communis L.) seed fractions and germplasm for ricin content, we investigated the use of enzyme‐linked immunosorbent assay (ELISA) methods to differentiate between ricin toxin and the related Ricinus communis agglutinin (RCA). Both proteins are based on a heterodimeric AB structure, with a common A chain. RCA comprises two dimers of A and B chains. Both proteins are found in the meal remaining after castor oil extraction and impede the commercial production of castor seed in the USA. We identified pairs of monoclonal antibodies (mAbs) that could distinguish between the structurally related proteins that share a common A chain. Antibody specificity was determined by ELISA and checked by immunoblotting. We found that mAb–mAb pairs afforded quantification of each castor protein, and that a mAb paired with a commercial polyclonal antibody provided detection of both with comparable sensitivity.  相似文献   
9.
To investigate the causes of brown heart (BH) in Conference pears, the contents of ascorbic acid (AA) and dehydroascorbic acid (DHAA) in fruits were studied during the first period of storage. AA was studied in 1999 and 2000, DHAA in 1999 only. Pears from normal and very late harvest stored immediately or after a delay in a controlled atmosphere with 2% O2 and low (0.7%) or high (5%) CO2 were compared. DHAA content did not change during storage in any treatment. AA decreased in storage according to an exponential model. The rate of AA loss was different in the two years and was higher in late‐harvest fruits and in those stored in 5% CO2. BH appeared in different treatments when AA decreased below a threshold, which was about 2 mg kg?1 fresh weight, corresponding to 5% of the AA content at harvest. The frequency and severity of symptoms depended linearly on the time spent by fruits in low‐ascorbate conditions. Advanced maturity at harvest and storage in high CO2 determine the appearance of BH and increase the rate of AA loss, probably through a reduction in the turnover of antioxidants. © 2002 Society of Chemical Industry  相似文献   
10.
Myrtaceae honeys produced in Sierra Morena (southern Spain, Andalusia) are obtained from both Eucalyptus camaldulensis and Myrtus communis, and honeys can be easily confused when classified as they come from the same botanical family. The characterisation was intended on the basis of their physicochemical, sensory and palynological properties. Cluster analysis (CA) and principal component analysis (PCA) allowed us to make a distinction between two honey profiles. The first one corresponds to the European sensory profile described for Eucalyptus unifloral honeys. The second profile, which sensory characteristics are absolutely different, has not been previously described. Classification of samples is proposed to be based on their pollen type and content and sensory attributes. Therefore, pollen type and content in E. camaldulensis and M. communis are required to distinguish Eucalyptus honey type from other honeys coming from Myrtaceae family. Sensory analysis identifies honey botanical source as well as palynological analysis: Eucalyptus sensory profile requires over 50% of E. camaldulensis and under 30% of M. communis pollen. Previously undefined sensory profile of myrtle honey is showed under 50% of E. camaldulensis and over 30% of M. communis pollen.  相似文献   
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