白蜡虫抗突变实验与主要功效成分分析

对白蜡虫的抗突变功能进行实验研究,并分析了甲壳素、多糖、维生素和黄酮类等.以白蜡虫为抗突变材料喂饲小鼠,48 h检测微核的发生率,各剂量组均比对照组的微核率低,其中高剂量组与对照有显著差异,抑制率为34.19%,说明白蜡虫能够对抗环磷酰胺产生的致突变作用,具有明显的抗突变功能.分析结果表明:白蜡虫含有2.14%甲壳素;7.2%的粗多糖,除蛋白后的多糖含量4.54%,多糖含量以葡萄糖计为28.4%,由葡萄糖、甘露糖和果糖组成,3种糖的摩尔比为5∶ 21∶ 1,白蜡虫多糖为一种杂多糖-蛋白复合物;白蜡虫还含有1.3%的总黄酮和多种维生素.甲壳素、多糖、维生素和黄酮类物质应为抗突变作用的主要功效成分.     

蟑螂水溶性多糖提取、分析及免疫活性研究

采用正交实验设计,以多糖含量为指标,对蟑螂水溶性多糖进行碱液和酶解提取研究;通过离子交换层析、凝胶层析对提取的多糖进行分级纯化,并对所得组分进行纯度鉴定和单糖分析;同时考察蟑螂粗多糖对正常小鼠的免疫活性.结果表明:酶解法提取的多糖含量较高,最佳实验条件是提取温度50℃、酶量200 μg·g-1,提取时间2 h.在此最佳实验条件下所得蟑螂多糖粗品中总糖含量为80 g·kg-1,蛋白含量为423 g·kg-1,氨基酸总量为333.4 g·kg-1;纯化后初步获得一个组分PWSPSC-2,多糖含量458 g·kg-1,蛋白含量392 g·kg-1,单糖组成Xyl:Ara:Glu:Man:Gal:GIcUA:GalUA=1.0:1.7:38.1:14.6:15.6:2.9:1.3;免疫活性实验显示,蟑螂粗多糖可以显著提高小鼠腹腔巨噬细胞吞噬指数、吞噬百分率及血清溶血素,表明蟑螂粗多糖可以明显增强小鼠的非特异性免疫和体液免疫功能.     

松仁多糖化学结构的初步分析

以松仁为原料,经热水提取、乙醇沉淀、DE-52纤维素柱层析和Sephadex G-100柱层析分离得到4个多糖组分(PNP1-a、PNP1-b、PNP2-a及PNP3-a).经GPC法测定,其相对分子质量依次为10.2×104、1.43×104、11.0×104和16.3×104.其中,PNP1-a由鼠李糖和葡萄糖组成,物质的量之比为1.00∶2.57;PNP1-b由阿拉伯糖和葡萄糖组成,物质的量之比为1.00∶4.03;PNP2-a和PNP3-a均由葡萄糖一种单糖组成.经酸水解、红外光谱(FT-IR)、紫外光谱(UV)和核磁共振光谱(NMR)对各组分进行结构分析,确定4种多糖均为β-构型的吡喃糖.     

不同枸杞叶片和果实中枸杞多糖含量的测定

采用苯酚-硫酸分光光度法对宁夏枸杞、新疆枸杞、枸杞叶片和果实中的多糖含量进行测定与分析,结果表明:宁夏枸杞、新疆枸杞、枸杞叶片中多糖含量分别为167.08μg·g-1、126.00μg·g-1、62.40μg·g-1,果实中的含量分别为80.00 mg·g-1、50.68 mg·g-1、29.64 mg·g-1,多糖含量高低依次均为宁夏枸杞新疆枸杞枸杞;果实和叶片中多糖含量具有显著正相关性,相关系数为0.97。     

Extraction of Maire Yew Polysaccharide and Its Structure

红豆杉枝叶经热水浸提、浓缩、醇沉、透析等工序制得一种红豆杉多糖,采用Sephadex G-100凝胶渗透法测定分子质量,采用气相色谱法测定其单糖组成,并测定了不同纯度红豆杉多糖的红外光谱.所得红豆杉多糖分子质量约为59.2ku,可视为由约365个糖残基构成的高分子化合物,其单糖残基鼠李糖、阿拉伯糖、甘露糖、葡萄糖、半乳糖数量比约为4∶6∶1∶1∶4.该红豆杉多糖分子结构中含有普通单糖、糖醛酸或氨基酸残基等,单糖主要以吡喃环形式存在、通过β-(1,3)苷键结合形成一种糖蛋白缀合物,Sevag法处理不能完全除去分子中的肽链.     

杜仲内树皮化学组成及抽提成分的研究

研究了杜仲内树皮及其抽提物的一般物、矿物质、脂肪酸与单糖的化学组成.结果表明,碳水化合物(92.97%)、钙(5.1769mg/g)、α - 亚麻酸(27.4%)及葡萄糖(130.51mg/g)分别是杜仲内树皮的一般物、矿物质、脂肪酸与单糖的主要组成成分.采用Sephadex LH - 20柱色谱及薄层色谱等方法,从其70%丙酮提取物水溶性部分分到5种化合物,经波谱分析及理化性质化合物分别鉴定为:紫云英苷(1)、异槲皮苷(2)、槲皮素 - 3 - O - 木糖葡萄糖苷(3)、异绿原酸 A(4)、异绿原酸 C(5).化合物3～5为首次从该植物中分得.     

红豆杉多糖的提取与结构初探

红豆杉枝叶经热水浸提、浓缩、醇沉、透析等工序制得一种红豆杉多糖,采用SephadexG-100凝胶渗透法测定分子质量,采用气相色谱法测定其单糖组成,并测定了不同纯度红豆杉多糖的红外光谱。所得红豆杉多糖分子质量约为59.2 ku,可视为由约365个糖残基构成的高分子化合物,其单糖残基鼠李糖、阿拉伯糖、甘露糖、葡萄糖、半乳糖数量比约为4∶6∶1∶1∶4。该红豆杉多糖分子结构中含有普通单糖、糖醛酸或氨基酸残基等,单糖主要以吡喃环形式存在、通过β-(1,3)苷键结合形成一种糖蛋白缀合物,Sevag法处理不能完全除去分子中的肽链。     

无梗五加果多糖与黄酮类化合物的研究

采用薄层色谱法对树脂纯化后的无梗五加果总黄酮进行了研究,表明以聚酰胺为固定相、微乳液为展开剂进行薄层层析鉴定效果最好,共分得9个组分.各种层析条件下的Rf值分析表明,无梗五加果中含药用成分金丝桃苷,未发现芦丁和槲皮素.采用HPLC法对经脱色、脱蛋白、DEAE52纤维素柱层析得到的主要多糖组分ASP-Ⅰ、ASP-Ⅱ进行单糖组成和纯度、相对分子质量(Mr)测定,表明无梗五加果多糖单糖组成为甘露糖、氨基葡萄糖、鼠李糖、葡萄糖醛酸、半乳糖醛酸、葡萄糖、半乳糖、木糖及岩藻糖,主要由Mr为21 800、147 000、45 400和18 100的4种均一多糖组成;其中,均一多糖ASP-Ⅰ由半乳糖和鼠李糖组成,物质的量之比为1∶0.7,Mr为18 100.对水提醇沉后得到的无梗五加果多糖进行生物活性研究表明,其具有抗疲劳和耐缺氧的能力.     

牛奶子果实性状及营养成分的产地与株间变异研究

对采自不同产地和单株的牛奶子的果实性状、氨基酸含量、番茄红素、β-胡萝卜素、Vc以及微量元素进行了分析.牛奶子浆果平均鲜质量0.13 g,变幅0.07～0.15 g.鲜果平均果肉率75.01%.6个单株的17种氨基酸总含量在146.596～179.634 mg·g-1之间,平均总含量为167.839 mg·g-1.其中谷氨酸含量最高,占氨基酸总含量的18.07%;其次精氨酸(11.66%)及天冬氨酸含量(10.78%),甲硫氨酸最低(0.84%),其余氨基酸均在7.00%以下.3个单株的番茄红素含量,最高的为342.000 mg·kg-1,最低为78.000 mg·kg-1,两者相差3.38倍,其含量是番茄的2.6～11.4倍.β-胡萝卜素平均含量为6.480 mg·kg-1,可溶性糖平均含量7.312 mg·kg-1,可滴定酸平均含量3.240 mg·g-1.Vc的平均含量为0.049 mg·g-1.Fe、Mn、Zn、Cu平均含量分别为97.881、77.553、23.384、12.129 mg·kg-1.K、Ca平均含量分别为11.190、3.720 mg·g-1.     

偃松松塔多糖的单糖组成分析及活性研究

偃松松塔经乙醇提取后,渣经热水提取、喷雾干燥、醇沉制备偃松松塔多糖(PPCP),并用苯酚硫酸法检测多糖的含量,气相色谱法测定PPCP的单糖组成。研究结果表明:PPCP是一种杂多糖,主要由阿拉伯糖、甘露糖、葡萄糖和半乳糖组成,具有典型的多糖红外光谱特征,4种单糖物质的量比为2.33∶1.00∶2.20∶1.94。通过测定PPCP清除DPPH·、·ABTS^+的能力以及还原能力评价PPCP抗氧化活性,然后通过体外实验评估其对RAW 264.7巨噬细胞免疫调节活性,结果表明:偃松松塔多糖有较强的自由基清除能力和Fe^3+还原能力,偃松松塔多糖以浓度依赖性方式表现出较强的抗氧化活性,在多糖质量浓度为2.0 g/L时,DPPH·的清除率(79.72%)达到最大,·ABTS^+清除率(39.63%)达到最大,其Fe^3+还原能力也达到最大值(0.78);松塔多糖能够刺激RAW 264.7巨噬细胞产生大量的NO,并没有对细胞增殖产生影响。     

Optical properties of bud scales and protochlorophyll(ide) forms in leaf primordia of closed and opened buds

The transmission spectra of bud scales of 14 woody species and the 77 K fluorescence emission spectra of the innermost leaf primordia of closed and opened buds of 37 woody species were studied. Pigment concentrations were determined in some species. Bud scales had low transmittance between 400 and 680 nm with a local minimum around 680 nm. Transmittance increased steeply above 680 nm and was > 80% in the 700-800 nm spectral region. Significant protochlorophyllide (Pchlide) accumulation was observed in leaf primordia of tightly packed, closed buds with relatively thick, dark bud scales. In common ash (Fraxinus excelsior L.) and Hungarian ash (Fraxinus angustifolia Vahl.), the innermost leaf primordia of the closed buds contained protochlorophyll (Pchl) and Pchlide (abbreviated as Pchl(ide)), but no chlorophyll. We observed Pchl(ide) forms with emission maxima at 633, 643 and 655 nm in these leaves. Complete transformation of Pchlide(655) (protochlorophyllide form with maximum emission at 655 nm) into Chlide(692) (chlorophyllide form with maximum emission at 692 nm) occurred after irradiation for 10 s. The innermost leaf primordia of the buds of four species (flowering ash (Fraxinus ornus L.), horse chestnut (Aesculus hippocastanum L.), tree of heaven (Ailanthus altissima P. Mill.) and common walnut (Juglans regia L.)) contained Pchl(ide)(633), Pchl(ide)(643) and Pchlide(655) as well as an emission band at 688 nm corresponding to a chlorophyll form. The Pchlide(655) was fully photoactive in these species. The outermost leaf primordia of these four species and the innermost leaf primordia of 28 other species contained all of the above described Pchl(ide) forms in various ratios but in small amounts. In addition, Chl forms were present and the main bands in the fluorescence emission spectra were at 690 or 740 nm, or both. The results indicate that Pchl(ide) accumulation occurs in leaf primordia in near darkness inside the tightly closed buds, where the bud scales and the external leaf primordia function as optical filters.     

Transient etiolation: protochlorophyll(ide) and chlorophyll forms in differentiating plastids of closed and breaking leaf buds of horse chestnut (Aesculus hippocastanum)

An accompanying paper reports the accumulation of photoactive protochlorophyllide (Pchlide) in the innermost leaf primordia of buds of many tree species. In this paper, we describe plastid differentiation, changes in pigment concentrations and spectral properties of bud scales and leaf primordia of horse chestnut (Aesculus hippocastanum L.) from January until the end of bud break in April. The bud scales contained plastids with grana, stroma thylakoids characteristic of chloroplasts and large dense bodies within the stroma. In January, proplastids and young chloroplasts were present in the leaf primordia, and the fluorescence spectra of the primordia were similar to those of green leaves except for a minor band at 630 nm, indicative of a protochlorophyll(ide). During bud break, the pigment concentrations of the green bud scales and the outermost leaf primordia increased, and Pchlide forms with emission maxima at 633, 644 and 655 nm accumulated in the middle and innermost leaf primordia. Depending on the position of the leaf primordia within the bud, their plastids and their pigment concentrations varied. Etio-chloroplasts with prolamellar bodies (PLBs) and prothylakoids with developing grana were observed in the innermost leaves. Besides the above-mentioned Pchlide forms, the middle and innnermost leaf primordia contained only a Chl band with an emission maximum at 686 nm. The outermost leaf primordia contained etio-chloroplasts with well-developed grana and small, narrow-type PLBs. These outermost leaves contained only chlorophyll forms like the mature green leaves. No Pchlide accumulation was observed after bud break, indicating that etiolation of the innermost and middle leaves is transient. The Pchlide forms and the plastid types of the primordia in buds grown in nature were similar to those of leaves of dark-germinated seedlings and to those of the leaf primordia of dark-forced buds. We conclude that transient etiolation occurs under natural conditions. The formation of PLBs and etio-chloroplasts and the accumulation of the light-dependent NADPH:protochlorophyllide oxidoreductase are involved in the natural greening process and ontogenesis of young leaf primordia of horse chestnut buds.     

Browsing Damage on Pine (Pinus sylvestris and P. contorta) by a migrating moose (Alces alces) Population in Winter: Relation to Habitat Composition and Road Barriers

In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads.     

Effects of Root Freezing on the Physiology and Growth of Picea glauca,Picea mariana and Pinus banksiana Seedlings Under Different Soil Moisture Regimes

The root systems of 2-yr-old Picea glauca, Picea mariana and Pinus banksiana seedlings were submitted to various frost temperatures during an artificial frost to induce different levels of root damage. Frost-damaged and control seedlings were placed in a greenhouse under high and low soil moisture regimes. Seedling growth and physiology were evaluated periodically. Seedling survival was reduced when root damage reached levels of 60-80%. Root systems of all three species showed partial to total recovery by the end of the experiment. In general, root freezing damage caused reductions in seedling growth, with these reductions becoming less significant over time. Root damage had little to no effect on black spruce and jack pine seedling physiology, while white spruce CO 2 uptake decreased with increasing root damage. Shoot nitrogen content of all three species decreased slightly with increasing root damage.     

Stand Structure in Pine,Spruce and Deciduous Forests: A Comparison Between Finnish and Russian Karelia

This study investigated the stand structure in pine, spruce and deciduous forests in the border district of Finland and Russia. A total of 46 mature forest stands was selected as pairs, the members of each pair being as similar as possible with respect to their forest site type, age, moisture and topography. The stands were then compared between the two countries by means of basal areas and number of stems. The proportions of dominating tree species were 2-12% lower, and correspondingly the proportions of secondary tree species higher, in Russian forests. The density of the forest stock was also higher in each forest type in Russia. The forests in the two countries differed most radically in terms of the abundance of dead trees. The amount was two to four times higher in Russian deciduous and spruce forests, and in pine forests the difference was 10-fold. The stand structures indicated that Russian coniferous stands, in particular, were more heterogeneous than intensively managed pine and spruce stands in Finland.     

Growth and Terminal Bud Formation in Picea abies Seedlings Grown with Alternating Diurnal Temperature and Different Light Qualities

The root collar diameter and the height:diameter ratio are of particular importance in container-grown seedlings where a high density in the containers may produce spindly seedlings. Temperature regimes and light quality are known to affect plant growth. The aim of this study was to identify responses in Picea abies (L.) Karst. seedlings grown with light providing different red:far-red ratios and under temperature regimes with alternating day (DT) and night temperature (NT) from negative (DT < NT) to positive (DT > NT) difference (DIF) between DT and NT. Experiments were conducted in controlled environment chambers and in a daylight phytotron. Only limited thermoperiodic responses appeared in P . abies seedlings with respect to seedling height and dry weight accumulation. The formation of terminal buds, however, was clearly delayed in seedlings grown at negative DIF. The results indicate a requirement for day extension light that is high in far-red, to prevent terminal bud formation under natural short-day conditions. An extended study should be conducted to clarify the minimum level of light intensity and the optimal light quality needed to prevent terminal bud formation under natural short-day conditions.     

CAD与建筑设计的关系

本文分析了CAD在设计中引起的正面和负面影响,并进行了系统的阐述,从而使设计者在应用中能够保持客观的态度。     

Natural Regeneration in Clear-cuts: Effects of Scarification,Slash Removal and Clear-cut Age

The effects of soil scarification (mounding), slash removal and clear-cut age on the natural regeneration in clear-cuts was evaluated using data from four sites in southern Sweden. The treatments were carried out during a good seed and establishment year for birch ( Betula pubescens Ehrh. and B. pendula Roth). Scarification had the strongest positive effect on the density of naturally regenerated seedlings, especially in birch, but also in pine ( Pinus sylvestris L.) and spruce [ Picea abies (L.) Karst]. Slash removal had a positive effect on birch density. No statistically significant effect of clear-cut age was found. In addition, no statistically significant interactions between clear-cut age and scarification or slash removal were found. The ingrowth of field vegetation was the fastest in areas that were not scarified, less rapid in areas scarified on old clear-cuts, and the slowest after scarification in fresh clear-cuts. In conclusion, it may be possible to control the density of birch during a good establishment year for birch. If birch is desired, the best combination of treatments is to remove the slash and scarify; otherwise, these treatments should be avoided.     

Risk Perception Among Non-industrial Private Forest Owners

Based on an enquiry, risk perception among non-industrial private forest owners is described in relation to climate change and forestry hazards. Of the respondents, 11% took action to remedy the effects of climate change. Out of a given set, hazards were ranked according to each respondent's experience of recent substantial financial loss to the estate and in relation to his or her willingness to make investments aimed at risk reduction. For each hazard, the respondent assessed the risk in four classes ranging from very high to negligible risk. Six hazards were considered most problematic in all three aspects: browsing damage, falling timber prices, damage by wind, spruce bark beetle, root rot and pine weevil. A majority of the respondents claimed to take action to reduce the risk associated with at least one hazard, while 35% did not know whether they did. Excluding climate change, the need for decision support was the largest in relation to damage by wind owing to a combination of perceived high risk and a high level of ignorance in relation to whether risk-reducing measures were taken.