ICP-AES法测定温州地区鼠尾藻中的微量元素

采用电感耦合等离子体原子发射光谱仪（ICP—AES）对温州地区野生和人工养殖鼠尾藻中11种微量元素的含量进行了测定。结果表明,鼠尾藻中钙、镁、铁、锌、锰、铜的含量丰富,温州地区野生和人工养殖的鼠尾藻所含各种微量元素存在差异,为鼠尾藻的进一步的开发利用提供科学依据。     

火焰原子吸收光谱法测定红松松针中微量元素含量

采用火焰原子吸收光谱法测定了长白山红松松针中K、Ca、Mg、Zn、Cu、Fe和Mn 7种金属元素含量。结果表明,在常量元素中K、Ca含量较高,微量元素中Fe、Zn含量较高,7种金属元素含量由高到低顺序分别为:K、Ca、Fe、Mg、Zn、Mn、Cu。可见松针中含有丰富的与健康密切相关的微量元素,具有较高的食用和药用价值。     

Anthraquinone Derivatives and an Orsellinic Acid Ester from the Marine Alga‐Derived Endophytic Fungus Eurotium cristatum EN‐220

Cultivation of the fungal strain Eurotium cristatum EN‐220, an endophyte obtained from the marine alga Sargassum thunbergii, resulted in the isolation of one new anthraquinone glycoside, 3‐O‐(α‐D ‐ribofuranosyl)questinol ( 1 ) and one new orsellinic acid ester, cristatumside A ( 2 ), together with three known aromatic glycosides, 3‐O‐(α‐D ‐ribofuranosyl)questin ( 3 ), isotorachrysone 6‐O‐α‐D ‐ribofuranoside ( 4 ), and asperflavin ribofuranoside ( 5 ), as well as three anthraquinone derivatives, asperflavin ( 6 ), eurorubrin ( 7 ), and (+)‐variecolorquinone A ( 8 ). The structures of these compounds were determined by extensive analysis of their spectroscopic data, as well as by their comparison with those in the literature. Each of the isolated compounds was evaluated for its antimicrobial activity and brine shrimp lethality.     

Bis(tributyltin) oxide as a wood preservative: Its conversion to tributyltin carboxylates in Pinus sylvestris

Tributyltin compounds have been successfully used for many years as wood preservatives, although their chemical nature in timber has not been fully elucidated. This study by ¹¹⁹Sn and ¹³C NMR spectroscopy has shown that, on impregnation into Pinus sylvestris sapwood, bis(tributyltin) oxide [(Bu₃Sn)₂O] is rapidly converted to tributyltin carboxylates (Bu₃SnOCO·R) via reaction with components of the wood resin. It is further suggested that the formation of these species is a prerequisite for the known disproportionation reaction which occurs in (Bu₃Sn)₂O-treated timber.     

Organosolv-pulping III

Formic acid pretreatment onPinus radiata D. Don was studied in order to improve the cellulose hydrolysis by commercial cellulase. The formic acid treatment effectively removed the lignin. A low substitution (formylation) and a crystallinity decrease of the cellulose in the pulp were observed. As consequence of these parameter changes, owing to the formic acid pretreatment on sawdust, a higher saccharification value was observed. The degree of saccharification increased when the degree of substitution (measured by titration) decreased and the portion of amorphous cellulose (measured via an X-ray technique) increased.Trichoderma reesei cellulase hydrolyzed the untreated and pretreated Pinus sawdust with formic acid in 25% and 56% of saccharification, respectively.     

Chemical composition of <Emphasis Type="Italic">Pinus silvestris</Emphasis> essential oil from contaminated areas

The chemical composition of Pinus silvestris essential oil from contaminated areas was studied. An apparent effect of radionuclides and toxic elements on the biosynthesis of terpenoids in common pine essential oil was found. Increasing contamination apparently increased the content of sesquiterpenes and O-containing substances and decreased the content of monoterpenes in the essential oil. The contents of α-pinene, camphene, and limonene increased and those of 3-carene, terpinolene, and β-pinene decreased in the monoterpene fraction. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 47–49, January–February, 2007.     

Curing Kinetics Of Tannin-Phenol-Formal- dehyde Adhesives As Determined By DSC

Differential scanning calorimetry (DSC) was used to compare the thermal curing of two adhesives suitable for using in the manufacture of exterior-grade plywood boards: a commercial phenol-formaldehyde (PF) resin, and a tannin-phenol-formaldehyde (TPF) resin developed in our laboratory. The experimental curves were well simulated by means of the Model Free Kinetics isoconversional method incorporated in the Mettler-Toledo STAR^e software package. The corresponding kinetic calculations predict that the TPF resin cures faster than the PF resin. This finding implies the possibility that the TPF resin may allow the achievement of higher productivity by permitting the use of shorter press times than with conventional PF resins. This revised version was published online in July 2006 with corrections to the Cover Date.     

气相色谱-质谱技术分析红松松塔挥发性成分

采用水蒸气蒸馏法，对红松松塔挥发性成分进行提取和研究，最佳蒸馏时间5.5h，挥发油提取率1.28％。利用气相色谱-质谱联用技术对提取的挥发油成分进行分析，共鉴定出32种化学成分，主要为单萜和倍半萜类化合物，其中相对含量较高的有α-蒎烯（44．258％）、D-柠檬烯（23．426％）、β-蒎烯（8.674％）、有石竹烯（3.462％）、β-月桂烯（3.018％）等。研究结果表明红松松塔挥发油中富含α-蒎烯、D-柠檬烯、石竹烯等多种具有药理活性的成分。因此，红松松塔是一种具有较好前景的天然药用资源。     

Optimization of Enzyme-Assisted Extraction and Purification of Flavonoids from Pinus koraiensis Nut-Coated Film and Antioxidant Activity Evaluation

Pinus koraiensis nut-coated film is a kind of by-product of nut processing, which has been shown to contain flavonoids, polyphenols, and other substances that can be used to produce natural antioxidant extracts. In this study, response surface methodology (RSM) was used to optimize the extraction process of flavonoids of P. koraiensis nut-coated film (PNF), and macroporous resin HPD600 was used to purify PNF (P-PNF). Its antioxidant activity was examined by DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging capacity, oxygen free radical absorption capacity (ORAC), total oxygen radical capture (TRAP), and iron ion reduction capacity. Under the ideal extraction conditions comprising a cellulase dosage of 90 U/g, a material/liquid ratio of 1:20 (g/mL), and an extraction time of 2 h, the PNF yield was 3.37%. Purification conditions were sample concentration of 2.0 mg/mL, pH of 5, water washing volume of 3 bed volume (BV), eluent ethanol concentration of 50%, and volume of 2 BV. The P-PNF recovery was 84.32%, and purity increased from 33.80% to 61.70%. Additionally, P-PNF showed increased antioxidant activity compared to PNF. Cumulatively, this study obtained the optimal values for the process parameters in order to achieve the maximum rates of extraction of PNF for economically optimal production at an industrial scale.     

Accumulation of Major,Minor and Trace Elements in Pine Needles (Pinus nigra) in Vienna (Austria)

Increasing heavy metal pollution in the environment and the fact that pine needles are good bio-monitors for air pollutants was the reason to investigate their accumulation in pine needles in Vienna (Austria). Pinus nigra is widespread over the city, thus allowing the study of different parameters influencing metal accumulation. The sampling sites were chosen based on traffic volume (low, medium, high). Fresh shoots were collected alongside one-year-old needles once per week from May to August 2015. The needle samples were washed and dried prior to acidic microwave-assisted digestion followed by quantitative determination using spectrometric methods. The investigation was focused on the following elements: Ag, Al, As, B, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, Pb, Se, Sr, U, V, and Zn. The one-year-old needles mainly contained higher contents of elements than fresh shoots; in many cases, the values differed statistically significantly. By correlating needle elemental contents with the sampling site, statistically significant differences were registered for the majority of the investigated elements. These differences originate from the local traffic situation, soil elemental levels, translocation processes, and not traffic-related sources. No general trend of metal accumulation from spring to summer was registered.