Absorption of flavonols derived from sea buckthorn (Hippophaë rhamnoides L.) and their effect on emerging risk factors for cardiovascular disease in humans

Sea buckthorn (Hippopha? rhamnoides L.) is a rich source of flavonols, especially isorhamnetin. Most prospective cohort studies have indicated some degree of inverse association between flavonoid intake and coronary heart disease. Animal and human studies suggest that sea buckthorn flavonoids may scavenge free radicals, lower blood viscosity, and enhance cardiac function. The effects of flavonol aglycones derived from sea buckthorn on the risk factors of cardiovascular disease as well as their absorption were studied in humans. The flavonols, ingested with oatmeal porridge, did not have a significant effect on the levels of oxidized low-density lipoprotein, C-reactive protein, and homocysteine, on the plasma antioxidant potential, or on the paraoxonase activity. Flavonols at two dosages in oatmeal porridge were rapidly absorbed, and a relatively small amount of sea buckthorn oil added to the porridge seemed to have increased the bioavailability of sea buckthorn flavonols consumed at the higher dose.     

Fatty acids and fat-soluble vitamins in salted herring (Clupea harengus) products

The fatty acid composition and contents of fat and fat-soluble vitamins of three salted products prepared from Icelandic herring were analyzed. The effects of storage on the products over their shelf life, 6 or 12 months, were investigated. The average oil content of salted, gutted herring and salted fillets in vacuum remained constant, 17 and 12% of wet weight, respectively. In the pickled product the oil content decreased during the 12 months of storage from 13 to 12%. The composition of the products was typical for herring, the most abundant fatty acids being oleic (18:1n-9), palmitic (16:0), cetoleic (22:1n-11), and gadoleic (20:1n-9) acids. Monounsaturated acids constituted clearly the main group with a proportion of >50% of all fatty acids. Eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3) comprised together >12% of all fatty acids. During storage, some hydrolysis of triacylglycerol (TAG) occurred, causing a slight reduction in practically all esterified fatty acids. In none of the three products was the loss of polyunsaturated fatty acids from TAG greater than the loss of saturated ones, indicating that the loss of EPA and DHA was not due to oxidation. After packing, the average content of vitamins A, D, and E in the products varied between 27 and 87 microg/100 g (wet weight), between 17-28 microg/100 g (wet weight), and between 77-120 microg/100 g (wet weight), respectively. During storage, the level of vitamin A decreased significantly, whereas no loss of vitamin D was observed. The content of vitamin E was low in all products and showed wide variation. When compared to the recommended daily intake, it could be concluded that the products investigated were good and stable sources of long-chain n-3 fatty acids (EPA, DHA) and vitamin D.     

三个沙棘亚种果实中的生物活性成分分析

本研究比较了来自中国、芬兰、俄罗斯的3个沙棘亚种中一系列亲水性与亲脂性的生物活性成分的含量与组成。在3个亚种中，中国沙棘果实中维生素C的含量最高，其值为9g／L果汁，其他两种为1～2g／L，果汁。新鲜果实中黄酮的含量在700mg／kg～2000mg／kg之间。各亚种中各种黄酮单体的比例也有变化。中国沙棘中木聚素含量(290～600ug／100g)要高于海滨沙棘(130～370ug／100g)。3种沙棘中，蒙古沙棘的油脂含量最高(种子中是12％，新鲜果实中为6％)。蒙古沙棘果实中棕榈油酸的含量最高。中国沙棘新鲜果实中生育酚和生育三烯酚总含量最高，但是在种子中的情况就正好相反。在3个沙棘亚种中，种子与新鲜果实的甾醇含量没有明显差别，含量分别在1200～1800mg／kg和250～300mg／kg之间。即使是在果实成熟以后，采收时间也会对某些活性物质有重要影响。在1998年8月末到9月底之间，海滨沙棘果实中维生素C的含量呈下降趋势，而在中国沙棘果实中类黄酮总量在9月底达到了顶峰。     

Localization of metastable atom beams with optical standing waves: nanolithography at the heisenberg limit

The spatially dependent de-excitation of a beam of metastable argon atoms, traveling through an optical standing wave, produced a periodic array of localized metastable atoms with position and momentum spreads approaching the limit stated by the Heisenberg uncertainty principle. Silicon and silicon dioxide substrates placed in the path of the atom beam were patterned by the metastable atoms. The de-excitation of metastable atoms upon collision with the surface promoted the deposition of a carbonaceous film from a vapor-phase hydrocarbon precursor. The resulting patterns were imaged both directly and after chemical etching. Thus, quantum-mechanical steady-state atom distributions can be used for sub-0.1-micrometer lithography.     

Quality components of sea buckthorn (Hippophae rhamnoides) varieties

The sensory quality and chemical constituents of juices from seven sea buckthorn (Hippophaerhamnoides L.) varieties were studied in two consecutive seasons. The juices were generally described as sour and astringent, with low sweetness and fruity flavor. The differences in sensory quality as well as in chemical composition between samples and years were significant (p < 0.05) in most parameters studied. The Chuiskaya variety was described as the sweetest, with the strongest fruity flavor, whereas the varieties Avgustinka, Botanicheskaya, Trofimovskaya, and Raisa were the sourest and most astringent. Total sugar (fructose and glucose) varied from 1.9 to 7.1 g/100 mL in juice, total acid (malic and quinic acids) from 3.1 to 5.1 g/100 mL, vitamin C from 29 to 176 mg/100 mL, and pulp oil from 0.7 to 3.6%. The soluble solids were between 7.4 and 12.6, the pH between 2.7 and 2.9, and the titrable acidity between 2.0 and 3.7. The redness was highest on Avgustinka and Raisa, but there were no differences in yellowness. Total sugar and the sugar/acid ratio correlated positively with sweetness and negatively with sourness and astringency, whereas total acid and titrable acidity correlated positively with sourness and astringency and negatively with sweetness.     

Determination of semivolatile compounds in Baltic herring (Clupea harengus membras) by supercritical fluid extraction-supercritical fluid chromatography-gas chromatography-mass spectrometry

The on-line supercritical fluid extraction-supercritical fluid chromatography-gas chromatography method was applied to the determination of volatile compounds of raw and baked Baltic herring (Clupea harengus membras). The analytes were extracted with supercritical carbon dioxide at 45 degrees C and 10 MPa pressure. After extraction, the volatiles and coeluted lipids were separated on-line using supercritical fluid chromatography and the volatile fraction was introduced directly into a gas chromatograph. In all, 30 compounds were identified from fish samples with mass spectrometry. The most abundant compounds in the fresh Baltic herrings were heptadecane and 1-heptadecene. When the fish were stored for 3-6 days at 6 degrees C, the total peak area of the volatiles began to increase and the proportions of short chain acids (acetic, propanoic, 2-methylpropanoic, and 3-methylbutanoic) also increased. After 8-9 days of storage, 3-methylbutanoic acid comprised about 36 and 40% of all volatiles in raw and baked herring, respectively.     

Esters from Bacterial Oxidation of Olefins

Identification of esters isolated from culture fluids of bacteria growing upon terminal olefins indicates that bacteria oxidize olefins at the saturated methyl group, leaving the double bond intact. The yeast Candida lipolytica produces alpha-glycols from olefins, presumably by attacking the double bond.     

Expression of Interleukin (IL)‐1β and IL‐1 Receptors Genes in the Hypothalamus of Anoestrous Ewes after Lipopolysaccharide Treatment

This study was designed to determine the effect of intravenous lipopolysaccharide (LPS) administration on the secretion of interleukin (IL)‐1β and IL‐1 receptors (IL‐1Rs) gene expression in the hypothalamus of anoestrous ewes. Gene expression of IL‐1β and its receptors was assayed by the real‐time polymerase chain reaction. The expression of IL‐1β in the hypothalamus was detected using Western blot. Our results showed that IL‐1β mRNA is transcribed in the ovine hypothalamus. Lipopolysaccharide increased (p ≤ 0.01) the IL‐1β gene expression in the pre‐optic area 2.4‐fold, the anterior hypothalamus (AHA) 3.4‐fold, the medial basal hypothalamus 3.7‐fold and the medial eminence 3.9‐fold. The pro‐form and mature form of IL‐1β protein were found in the hypothalamus after endotoxin injection. In general, the endotoxin also increased more than two times (p ≤ 0.01) the expression of IL‐1 receptor type I (IL‐1R1) and type II (IL‐1R2) genes in the hypothalamus, except the AHA, where the number of IL‐1R2 mRNA was extremely low and not sufficient to the quantitative analysis. These results demonstrate that the peripheral immune/inflammatory challenge increases the IL‐1β expression in the hypothalamus. This endogenous IL‐1β seems to be involved in the modulation of processes which are regulated at the hypothalamic level. One of these processes could be a reproduction.     

配合饲料和饲料添加剂

前言目前畜牧生产的高效率是以下几方面因素综合作用的结果:1.畜牧生产者能迅速地接受新的饲养管理技术;2.遗传、营养和饲养管理方面的研究取得了非常有价值的成果,能够以尽可能低的成本生产优质的畜产品;3.政府鼓励科研的发展,为畜牧工作提出合理建议并制订必要的法规。在科学计算的基础上,应用配合饲料,特别是全价饲料(粉料或顺粒料)喂猪和禽能够迅速有效地将营养研究成果和革新技术应用到实际中去。全价饲料可以节省劳力,提高饲料