Properties of α-, γ-, and δ-tocopherol in purified fish oil triacylglycerols

The effect of α-tocopherol (αTOH) (50–2000 ppm), γ-tocopherol (γTOH) (100–2000 ppm), and δ-tocopherol (δTOH) (100–2000 ppm) on the formation and decomposition of hydroperoxides in purified fish oil triacylglycerols (TAG) was studied. The tests were conducted at 30°C in the dark. Purified fish oil TAG oxidized very rapidly with no apparent induction period. The relative ability of the tocopherols to retard the formation of hydroperoxides decreased in the order αTOH> γTOH>δTOH at a low level of addition (100 ppm), but a reverse order of activity was found when the initial tocopherol concentration was 1000 ppm. This dependence of relative antioxidant activity on tocopherol concentration was caused by the existence of concentrations for maximal antioxidant activity for αTOH and for γTOH. An inversion of activity, on the basis of hydroperoxide formation, was observed for αTOH at 100 ppm and for γTOH at 500 ppm, whereas the antioxidant activity of δTOH increased with level of addition up to 1500–2000 ppm. None of the tocopherols displayed any prooxidant activity. All three tocopherols strongly retarded the formation of volatile secondary oxidation products in a concentration-dependent manner. At concentrations above about 250 ppm there appeared to be a linear relationship between rate of consumption of αTOH and initial αTOH concentration, in accordance with the linear relationship observed between the initial rate of formation of hydroperoxides and the initial αTOH concentration. The rate of consumption of γTOH also increased with initial concentration, but to a lesser extent than for αTOH. At high levels of addition the rate of consumption of δTOH was independent of initial concentration, appearing to reflect the greater stability of this tocopherol homolog and participation in reactions with lipid peroxyl radicals only. Presented in part at the AOCS annual meeting in San Diego, California, April 2000.     

Determination of (+)-, (−)-, and total gossypol in cottonseed by high-performance liquid chromatography

Gossypol, a pigment in cottonseed, is a polyphenolic, binaphthyl dialdehyde. Due to steric hindrance between the functional groups of the molecule at the bond connecting the two naphthyl rings, gossypol exists as (+)- and (−)-isomers. Gossypol is physiologically active with the (−)-isomer appearing to be more active and causing temporary infertility in males. It is thus important to know the amounts of isomers in livestock feeds. A quantitative high-performance liquid chromatography (HPLC) procedure was developed for the separation of (+)- and (−)-gossypol contained in cottonseed. This method involves derivatization of gossypol with (R)-(−)-2-amino-1-propanol followed by HPLC separation employing either a Phenomenex Prodigy (5 μ, ODS-3, 100 × 3.2 mm) or a MetaChem Inertsil (5 μ, ODS-3, 100 × 3.0 mm) reversed-phase column eluted with 80% acetonitrile and 20% 10 mM KH₂PO₄ adjusted to pH 3.0 with H₃PO₄ at 1.0 mL/min. The (+)- and (−)-gossypol-2- amino-1-propanol complexes eluted at roughly 1.4 and 2.6 min, respectively. It was found that gossypol from Upland (Gossypium hirsutum) seed was rich in the (+)-enantiomer, with the (+)- and (−)-enantiomers in a ratio of about 65:35, respectively, while gossypol from the seed of a Pima (G. barbadense) cultivar (S-6) was slightly richer in the (−)-enantiomer (46.8:53.2). Deceased.     

Synthesis,PASS-Predication and in Vitro Antimicrobial Activity of Benzyl 4-O-benzoyl-α-l-rhamnopyranoside Derivatives

Benzyl α-l-rhamnopyranoside 4, obtained by both conventional and microwave assisted glycosidation techniques, was subjected to 2,3-O-isopropylidene protection to yield compound 5 which on benzoylation and subsequent deprotection of isopropylidene group gave the desired 4-O-benzoylrhamnopyranoside 7 in reasonable yield. Di-O-acetyl derivative of benzoate 7 was prepared to get newer rhamnopyranoside. The structure activity relationship (SAR) of the designed compounds was performed along with the prediction of activity spectra for substances (PASS) training set. Experimental studies based on antimicrobial activities verified the predictions obtained by the PASS software. Protected rhamnopyranosides 5 and 6 exhibited slight distortion from regular ¹C₄ conformation, probably due to the fusion of pyranose and isopropylidene ring. Synthesized rhamnopyranosides 4–8 were employed as test chemicals for in vitro antimicrobial evaluation against eight human pathogenic bacteria and two fungi. Antimicrobial and SAR study showed that the rhamnopyranosides were prone against fungal organisms as compared to that of the bacterial pathogens. Interestingly, PASS prediction of the rhamnopyranoside derivatives 4–8 were 0.49 < P_a < 0.60 (where P_a is probability ‘to be active’) as antibacterial and 0.65 < P_a < 0.73 as antifungal activities, which showed significant agreement with experimental data, suggesting rhamnopyranoside derivatives 4–8 were more active against pathogenic fungi as compared to human pathogenic bacteria thus, there is a more than 50% chance that the rhamnopyranoside derivative structures 4–8 have not been reported with antimicrobial activity, making it a possible valuable lead compound.     

Contents of α-O-4 and β-O-4 Bonds in Native Lignin and Isolated Lignin Preparations

An analytical calculation method for the estimation of the contents of alkyl aryl ether bonds (α-O-4 and β-O-4) in lignin was developed. In the framework of the method, Alkyl–O–Aryl type bonds are described as coupled phenolic hydroxyls (OH_phen). The method is based on the balance equation including the free and coupled OH_phen contents in dissolved and residual lignins, on the one hand, and their respective contents in native lignin, on the other. The free OH_phen content is calculated on the basis of the OH_phen contents of dissolved and residual lignin, determined by the aminolysis method in the course of kraft cooking of softwood. The calculation results for soluble lignin preparations are in good agreement with the 13C NMR (nuclear magnetic resonance) spectral data for the solutions. The content of Alkyl–O–Aryl bonds in native softwood (pine, spruce) lignin was estimated at 79/100 PPU (phenylpropane unit). In isolated lignin preparations, the contents of these bonds decrease in the sequence: Freudenberg lignin (71/100 PPU)> Bjorkman lignin (61/100 PPU)> Pepper lignin (44/100 PPU). Dissolved alkaline lignin still contains small amounts of Alkyl–O–Aryl bonds (36/100 PPU in soda lignin and an average of 23/100 PPU in soda-AQ lignin, kraft lignin, and kraft-AQ lignin). Residual lignin which represents the fraction of native lignin with inter-unit bonds resistant to kraft pulping contains 66/100 PPU of such bonds. A relatively high content of Alkyl–O–Aryl bonds (61/100 PPU) is preserved in technical hydrolysis lignins.     

(1S,3R,4R)-3-氨基-4-羟基环己烷-1-羧酸乙酯的合成

本研究以(S)-3-环己烯-1-羧酸为原料,经三步反应得到目标产物(1S,3R,4R)-3-氨基-4-羟基环己烷-1-羧酸乙酯,确定了一条可以进行中试放大的工艺路线.     

Electrical conductance and apparent molar volumes of Al(ClO4)3, Be(ClO4)2, and Cu(ClO4)2 in N,N-dimethylacetamide solutions at 25°C

Equivalent conductances and apparent molar volumes of Al(ClO₄)₃, Be(ClO₄)₂, and Cu(ClO₄)₂ in N,N-dimethylacetamide at 25°C are reported. The limiting equivalent conductances, the first step association constants, and the apparent molar volumes at infinite dilution are derived and discussed in terms of influence of nature of cation on the properties of DMA-solvated cations.     

Ascorbic acid consumption and serum levels in smokers and non-smokers adult men in Hermosillo,Sonora, México

Ascorbic acid is one of the important antioxidant nutrients that can aid in the prevention of oxidative cellular damage. Adequate dietary intake is essential as humans can not synthesize this vitamin. It has been reported that smokers require higher dietary intakes to maintain their serum levels. The objective of this study was to determine serum levels of ascorbic acid in young male smokers and non smokers in the city of Hermosillo, Sonora, Mexico. In addition, their dietary intake of ascorbic acid was determined by a 24 h dietary recall. The dietary intake of ascorbic acid in 12 smokers was 64 +/- 11 mg/d and in 13 non smokers it was 70 +/- 12 mg/d. The smokers in this study did not meet the dietary recommendation of 100 mg/d. Serum ascorbic acid values in smokers and non smokers were 24.2 +/- 6.9 mumol/L and 30.9 +/- 3.7 mumol/L respectively. No significant difference was found among the 2 groups. Although the average serum ascorbic acid values fell within the range considered normal, 50% of the smokers had individual values that were below 23 mumol/L, indicating that these subjects have hipovitaminosis. A positive correlation between intake and serum levels was obtained for smokers (r = 0.71; p = 0.03). The results of this study suggest smokers may be at increased risk for chronic diseases due to their low intake and low serum levels of ascorbic acid.     

2,4,6-三（4,-羧基-1,-羧丙氨基）-1,3,5-三嗪

用三聚氯氰和谷氨酸为原料,合成2,4,6-三（4,-羧基-1,-羧丙氨基）-1,3,5-三嗪（TGAT）。讨论了反应物配比、反应时间、反应温度对产率的影响。FTIR及1HNMR表征了衍生物的结构。通过对产物进行阻垢实验发现,该类型阻垢剂对碳酸钙有良好的阻垢效果。通过扫描电镜考察了阻垢剂碳酸钙垢晶型的变化,结果表明TGAT可使碳酸钙垢晶型完全扭曲,形成球霰石晶体,从而达到阻垢目的。     

Genistein Induces Increase in Fluid pH,Na+ and HCO3? Concentration,SLC26A6 and SLC4A4 (NBCe1)-B Expression in the Uteri of Ovariectomized Rats

Genistein has been reported to stimulate luminal HCO₃⁻ secretion. We hypothesized that genistein mediates this effect via SLC26A6 and SLC4A4 (NBCe1) transporters. Our study aimed to: investigate changes in uterine fluid pH, Na⁺ and HCO₃⁻ concentration and expression of uterine SLC26A6 and NBCe1 under genistein effect. Ovariectomized adult female rats received 25, 50 and 100 mg/kg/day genistein for a week with and without ICI 182780. A day after the last injection, in vivo uterine perfusion was performed to collect uterine fluid for Na⁺, HCO₃⁻ and pH determination. The animals were then sacrificed and uteri were removed for mRNA and protein expression analyses. SLC26A6 and NBCe1-A and NBCe1-B distribution were visualized by immunohistochemistry (IHC). Genistein at 50 and 100 mg/kg/day stimulates uterine fluid pH, Na⁺ and HCO₃⁻ concentration increase. Genistein at 100 mg/kg/day up-regulates the expression of SLC26A6 and SLC4A4 mRNA, which were reduced following concomitant ICI 182780 administration. In parallel, SLC26A6 and NBCe1-B protein expression were also increased following high dose genistein treatment and were localized mainly at the apical membrane of the luminal epithelia. SLC26A6 and NBCe1-B up-regulation by genistein could be responsible for the observed increase in the uterine fluid pH, Na⁺ and HCO₃⁻ concentration under this condition.     

肉桂酸4-(4-乙酰基-5-甲基-2-吡咯基)-2',3',4'-三羟基丁酯的合成及其卷烟加香应用

碱性条件下,以氨基葡萄糖盐酸盐与乙酰丙酮为原料,在水溶液中加热回流8 h,得到2-甲基-3-乙酰基-5-1',2',3',4'-四羟丁基吡咯。并以此为原料,以DCC为缩合剂,与肉桂酸反应合成了目标化合物肉桂酸4-(4-乙酰基-5-甲基-2-吡咯基)-2',3',4'-三羟基丁酯,通过1HNMR、13CNMR、IR、HRMS等方法对产物的结构进行了验证。研究了目标物在300、600、900℃的热裂解行为,并对目标物进行卷烟加香研究,结果表明:目标化合物可裂解出苯甲醛、2-甲基吡啶、金合欢醇等香气成分,按烟丝质量0.2%添加该物质可起到改善卷烟的吃味与香气质,降低刺激性,改善余味的作用。     

(2S,4S)-4-羟脯氨酸的合成工艺研究

以(2S,4R)-4-羟脯氨酸为基础原料,以水为介质,利用三苯基膦和醇的Mitsunobu合成反应,改变其构型得到(2S,4S)-4-羟脯氨酸。此方法在现有合成路线基础上有所改进,在实验过程中探索反应物配比对各步反应收率的影响,得到实验的最优条件。并对产物进行表征及纯度分析,确定为(2S,4S)-4-羟脯氨酸,纯度为87.2%,收率93.3%。     

4-(4',4'-二苯基-1',3'-丁二烯基)-N,N-二(4″-甲基苯基)苯胺的合成及性能

该文通过Vilsmeier反应,用4,4'-二甲基三苯胺制得了4-[N,N-二(4'-甲基苯基)]氨基苯甲醛(Ⅰ),收率85.4%;Ⅰ与1,1-二苯基-3-氯丙烯经Wittig反应合成了三苯胺衍生物4-(4',4'-二苯基-1',3'-丁二烯基)-N,N-二(4″-甲基苯基)苯胺(Ⅱ),收率43.0%,HPLC面积归一法测定目的产物为99.64%.通过紫外光谱、红外光谱、质谱和元素分析对产物的组成和结构进行了鉴定.用Ⅱ作空穴传输材料制成功能分离型有机光导体,测得其静电特性数据为V0=-580 V,VR=-20 V,E1/2=0.50 lx*s,表明Ⅱ具有优良的空穴传输特性.     

Absolute Configuration of β- and α-Asymmetric Carbons within β-O-4-Structures in Hardwood Lignin

In this study, we investigated the proportion of erythro- and threo-forms of β-O-4-ether structures and their enantiomeric compositions in hardwood lignin by applying the ozonation method to birch wood meal. Optical activity was not substantially observed in either the erythronic or threonic acids obtained as the ozonation products of β-O-4-structures in birch wood meal. The proportions of the four stereoisomeric forms {(αS,βR)-erythro, (αR,βR)-threo, (αS,βS)-threo, and (αR,βS)-erythro forms} were estimated to be 37-38%, 13-14%, 12-13%, and 36-37% based on the yields of erythronic and threonic acids, and on their optical activities. The proportions suggest that the entire components of β-O-4-ether structures in birch wood lignin have R- and S-configurations at the β-carbon in approximately the same quantities {(βR)-β-O-4-structure: (βS)-β-O-4-structure = 50–52:48–50}; i.e., that the β-ether structures are essentially racemic. This estimation implies that, during lignin biosynthesis, an equal number of enantiomeric forms of β-O-4-bonded quinone methides were formed by radical coupling reactions.     

4-Hydroxyderricin,as a PPARγ Agonist,Promotes Adipogenesis,Adiponectin Secretion,and Glucose Uptake in 3T3-L1 Cells

Adipocyte differentiation plays a pivotal role in maintaining the production of small‐size adipocytes with insulin sensitivity, and impaired adipogenesis is implicated in insulin resistance. 4‐Hydroxyderricin (4‐HD), a phytochemical component of Angelica keiskei, possesses diverse biological properties such as anti‐inflammatory, antidiabetic, and antitumor. In the present study, we investigated the effects of 4‐HD on adipocyte differentiation. 4‐HD promoted lipid accumulation in 3T3‐L1 cells, upregulated both peroxisome proliferator‐activated receptor (PPAR)‐γ mRNA and protein expression, and acted as a ligand for PPARγ in the luciferase assay. Moreover, 4‐HD increased the mRNA and protein expression levels of adiponectin. Additionally, it promoted insulin‐dependent glucose uptake into 3T3‐L1 adipocytes and increased Akt phosphorylation and glucose transporter (GLUT) 4 mRNA expression. In summary, these findings suggest that 4‐HD, which promoted adipogenesis and insulin sensitivity in 3T3‐L1 cells, might be a phytochemical with potent insulin‐sensitizing effects.     

Sillimanite,Kyanite and Andalusite in China and Their Applications Part Ⅰ:Their Reserve,Distribution and Characteristics

Sillimanite, kyanite and andalusite areadvantageous natural refractory raw materials foraluminosilicate refractories to attain improved keyproperties. This paper are divided into two parts tointroduce their resource and technical characteristicin the first part, and their applications in refracto-ries in the second part to be succeeded. In this part,based on authors' knowledge and sources, informa-tion on their reserve, distribution, composition and