云南引种的元宝枫果实性状变异研究

以云南引种的46株元宝枫的果实为研究材料,对其果实的9个性状变异和各性状间的相关性进行了分析研究。结果表明,(1)果实性状的株间变异较株内变异显著;(2)果实各性状变异系数由大到小依次为空壳比率、果实厚度、种子千粒重、果实千粒重、着生痕长度、种子厚度、果实宽度、带翅果实长度、果实长度;(3)果实千粒重与种子千粒重呈高度正相关,与果实宽度、种子厚度、果实厚度呈显著正相关,与带翅果实长度、着生痕长度及果实长度呈低度正相关。种子千粒重除了与果实千粒重呈高度正相关外,还和带翅果实长度、种子厚度、果实厚度呈显著正相关,而且和果实宽度呈低度正相关。以此评选出引种地果实性状优良、产量高的元宝枫单株。     

Heptaketides with antiviral activity from three endolichenic fungal strains Nigrospora sp., Alternaria sp. and Phialophora sp

Two new heptaketides, (+)-(2S,3S,4aS)-altenuene (1a) and (-)-(2S,3S,4aR)-isoaltenuene (2a), together with six known compounds, (-)-(2R,3R,4aR)-altenuene (1b), (+)-(2R,3R,4aS)-isoaltenuene (2b), 5'-methoxy-6-methyl-biphenyl-3,4,3'-triol (3), alternariol (4), alternariol-9-methyl ether (5), and 4-hydroxyalternariol-9-methyl ether (6) were isolated from the EtOAc extract of an endolichenic fungal strain Nigrospora sphaerica (No.83-1-1-2). Compounds 1a and 1b were separated from enantiomers 1 by chiral HPLC, and so were 2a and 2b from enantiomers 2. Interestingly, 1-6 were also obtained from other two endolichenic fungal strains Alternaria alternata (No.58-8-4-1) and Phialophora sp. (No.96-1-8-1). The structures of 1-6 were elucidated by means of MS, HR-MS, NMR, and X-ray diffraction. Furthermore, the absolute configurations of 1a-2b were determined by CD experiments and CD calculation. Of these compounds, 4 and 5 showed antiviral activity against herpes simplex virus (HSV) in vitro, with IC(50) values of 13.5 and 21.3 μM, and with selective index (SI) values of 26.5 and 17.1, respectively.     

New cytotoxic quinolone alkaloids from fruits of Evodia rutaecarpa

Three new quinolone alkaloids, 1-methyl-2-[7-hydroxy-(E)-9-tridecenyl]-4(1H)-quinolone (1), 1-methyl-2-[(Z)-4-nonenyl]-4(1H)-quinolone (2), 1-methyl-2-[(1E,5Z)-1,5-undecadienyl]-4(1H)-quinolone (3) and one new natural product, 1-methyl-2-[(E)-1-undecenyl]-4(1H)-quinolone (4), were isolated from the dried and nearly ripe fruits of Evodia rutaecarpa (Juss.) Benth., along with thirteen known compounds (5-17). In addition, one new artificial product, 1-methyl-2-[7-carbonyl-(E)-9-tridecenyl]-4(1H)-quinolone (1A) was also obtained. The structures of these compounds were determined by spectroscopic analyses. The cytotoxic activities of all of the compounds against the human cancer cell lines HL-60, N-87, H-460, and Hep G(2) cells were evaluated by MTT assay. The results showed that these alkaloids inhibited cell proliferation with IC(50) values between 14μM and 22μM.     

用二次正交旋转组合设计优化马占相思增殖培养基

在马占相思组织培养初步取得成功的基础上，采用二次正交旋转组合设计对马占相思增殖培养基进行优化，建立增殖率(Y)对Ca^2 浓度(X1)、6-BA浓度(X2)及NAA浓度(X3)3个试验因子的正交回归模型：Y=2．280-0．168X1-0．259X2 0．185X1^2-0．210X2^2 0．167X3^2 0．326X1X2。从模型推知，当Ca^2 浓度为0．58倍常规MS培养基浓度(255g／L)，6BA为0．76mg／L，NAA为0．16mg／L时，增殖率达最大值为4．32，实验结果与预测值相符。     

Gas exchange and dry matter allocation responses to elevation of atmospheric CO(2) concentration in seedlings of three tree species

Photosynthetic rates of 13-month-old Pinus radiata D. Don, Nothofagus fusca (Hook f.) ?rst. and Pseudotsuga menziesii (Mirb.) Franco seedlings grown and measured at elevated atmospheric concentrations of CO(2) (~620 microl l(-1)) were 32 to 55% greater than those of seedlings grown and measured at ambient (~310 microl l(-1)) concentrations of CO(2). Seedlings grown in ambient and elevated concentrations of CO(2) had similar rates of photosynthesis when measured at ~620 microl l(-1) CO(2), but when measured at ~310 microl l(-1) CO(2), the P. radiata and N. fusca seedlings which were grown at elevated CO(2) had lower rates of photosynthesis than the seedlings grown at an ambient concentration of CO(2). Stomatal conductances in general were lower when measured at ~620 microl l(-1) CO(2) than at ~310 microl l(-1) CO(2). Stomatal conductances declined in all species grown at both CO(2) concentrations when the leaf-air water vapor concentration gradient (DeltaW) was increased from 10 to 20 mmol H(2)O mol(-1) air. The percent enhancement in photosynthesis for P. radiata and P. menziesii at elevated CO(2) was greater at 20 mmol than at 10 mmol DeltaW, suggesting that elevated CO(2) may moderate the effects of atmospheric water stress. Dry matter allocation patterns were not significantly different for plants grown in ambient or high CO(2) air.     

Steroidal saponins from Smilacina japonica

Three new steroidal saponins, japonicoside A (1), japonicoside B (2) and japonicoside C (3) were isolated from the dried rhizomes and roots of Smilacina japonica A. Gray. Their structures were elucidated as (25S)-5α-spirostan-9(11)-en-3β-ol 3-O-β-D-glucopyranosyl-(1→2)-[β-D-xylopyranosyl-(1→3)]-β-D-glucopyranosyl-(1→4)-β-D-galactopyranoside (1), (25S)-5α-spirostan-9(11)-en-3β,17α-diol 3-O-β-D-glucopyranosyl-(1→2)-[β-D-xylopyranosyl-(1→3)]-β-D-glucopyranosyl-(1→4)-β-D-galactopyranoside (2) and (25S)-5α-spirostan-9(11)-en-3β,17α,24α-triol 3-O-β-D-glucopyranosyl-(1→2)-[β-D-xylopyranosyl-(1→3)]-β-D-glucopyranosyl-(1→4)-β-D-galactopyranoside (3) on the basis of chemical methods and detailed spectroscopic analysis, including 1D, 2D NMR and HR-ESI-MS. The cytotoxicity of isolated compounds was evaluated in vitro for cytotoxic properties against human hepatocellular carcinoma cells (SMMC-7221) and human colorectal adenocarcinoma cells (DLD-1), respectively.     

Carbon dioxide exchange of developing avocado (Persea americana Mill.) fruit

Net efflux of CO(2) from attached avocado (Persea americana Mill.) fruit was measured periodically from three weeks after anthesis to fruit maturity. Net CO(2) exchange was determined in daylight (light respiration, R(l)) at a photosynthetic photon flux (PPF) greater than 600 micromol m(-1) s(-1), and in the dark (dark respiration, R(d)). Dark respiration and R(l) were highest during the early cell division stage of fruit growth (about 25 and 22 nmol CO(2) g(dw) (-1) s(-1), respectively) and decreased gradually until fruit maturity to about 1 and 0.5 nmol CO(2) nmol CO(2) g(dw) (-1) s(-1), respectively. Fruit photosynthesis, calculated from the difference between R(d) and R(l), ranged from 0.5 to 3.1 nmol CO(2) g(dw) (-1) s(-1). Net rate of CO(2) assimilation on a fruit dry weight basis was highest during the early stages of fruit growth and reached the lowest rate at fruit maturity. Net rate of CO(2) assimilation of fruit exposed to light was 0.4 to 2.5% of that for fully expanded leaves. Although the relative amount of carbon assimilated by the fruit was small compared with the total amount of carbon assimilated by the leaves, the data indicate that avocado fruit contribute to their own carbon requirement by means of CO(2) assimilated in the light.     

Leaf conductance and CO(2) assimilation of Larix gmelinii growing in an eastern Siberian boreal forest

In July 1993, we measured leaf conductance, carbon dioxide (CO(2)) assimilation, and transpiration in a Larix gmelinii (Rupr.) Rupr. ex Kuzen forest in eastern Siberia. At the CO(2) concentration of ambient air, maximum values (mean of 10 highest measured values) for CO(2) assimilation, transpiration and leaf conductance for water vapor were 10.1 micro mol m(-2) s(-1), 3.9 mmol m(-2) s(-1) and 365 mmol m(-2) s(-1), respectively. The corresponding mean values, which were much lower than the maximum values, were 2.7 micro mol m(-2) s(-1), 1.0 mmol m(-2) s(-1) and 56 mmol m(-2) s(-1). The mean values were similar to those of Vaccinium species in the herb layer. The large differences between maximum and actual performance were the result of structural and physiological variations within the tree crowns and between trees that reduced maximum assimilation and leaf conductance by about 40 and 60%, respectively. Thus, maximum assimilation and conductance values averaged over the canopy were 6.1 micro mol m(-2) s(-1) and 146 mmol m(-2) s(-1), respectively. Dry air caused stomatal closure, which reduced assimilation by an additional 26%. Low irradiances in the morning and evening had a minor effect (-6%). Daily canopy transpiration was estimated to be 1.45 mm day(-1), which is higher than the value of 0.94 mm day(-1) measured by eddy covariance, but similar to the value of 1.45 mm day(-1) calculated from the energy balance and soil evaporation, and less than the value of 2.1 mm day(-1) measured by xylem flux. Daytime canopy carbon assimilation, expressed on a ground area basis, was 0.217 mol m(-2) day(-1), which is higher than the value measured by eddy flux (0.162 mol m(-2) day(-1) including soil respiration). We discuss the regulation of leaf gas exchange in Larix under the extreme climatic conditions of eastern Siberia (temperature > 35 degrees C and vapor pressure deficit > 5.0 kPa).     

New antifungal constituents from Terminalia alata

The roots of Terminalia alata yielded three new glycosides: 3,3'-di-O-methylellagic acid 4-O-beta-D-glucopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->2)-alpha-L-arabinopyranoside (1), 5,7,2'-tri-O-methylflavanone 4'-O-alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranoside (2), and 2alpha,3beta, 19beta,23-tetrahydroxyolean-12-en-28-oic acid 3-O-beta-D-galactopyranosyl-(1-->3)-beta-D-glucopyranoside-28-O-beta-D-glucopyranoside (3). Compounds 2 and 3 displayed antifungal activity.     

Effects of leaf,shoot and fruit development on photosynthesis of lychee trees (Litchi chinensis)

Changes in gas exchange with leaf age and fruit growth were determined in lychee trees (Litchi chinensis Sonn.) growing in subtropical Queensland (27 degrees S). Leaves expanded in a sigmoid pattern over 50 days during spring, with net CO2 assimilation (A) increasing from -4.1 +/- 0.9 to 8.3 +/- 0.5 micromol m-2 s-1 as the leaves changed from soft and red, to soft and light green, to hard and dark green. Over the same period, dark respiration (Rd) decreased from 5.0 +/- 0.8 to 2.0 +/- 0.1 micromol CO2 m-2 s-1. Net CO2 assimilation was above zero about 30 days after leaf emergence or when the leaves were half fully expanded. Chlorophyll concentrations increased from 0.7 +/- 0.2 mg g-1 in young red leaves to 10.3 +/- 0.7 mg g-1 in dark green leaves, along with stomatal conductance (gs, from 0.16 +/- 0.09 to 0.47 +/- 0.17 mol H2O m-2 s-1). Fruit growth was sigmoidal, with maximum values of fresh mass (29 g), dry mass (6 g) and fruit surface area (39 cm2) occurring 97 to 115 days after fruit set. Fruit CO2 exchange in the light (Rl) and dark (Rd) decreased from fruit set to fruit maturity, whether expressed on a surface area (10 to 3 micromol CO2 m-2 s-1 and 20 to 3 micromol CO2 m-2 s-1, respectively) or on a dry mass basis (24 to 2 nmol CO2 g-1 s-1 and 33 to 2 nmol CO2 g-1 s-1, respectively). Photosynthesis never exceeded respiration, however, the difference between Rl and Rd was greatest in young green fruit (4 to 8 micromol CO2 m-2 s-1). About 90% of the carbon required for fruit growth was accounted for in the dry matter of the fruit, with the remainder required for respiration. Fruit photosynthesis contributed about 3% of the total carbon requirement of the fruit over the season. Fruit growth was mainly dependent on CO2 assimilation in recently expanded dark green leaves.     

Sulfate concentrations in Norway spruce needles in relation to atmospheric SO(2): a comparison of trees from various forests in Germany with trees fumigated with SO(2) in growth chambers

Concentrations of inorganic sulfur, organic sulfur and water-soluble cations and anions were determined in needles of young Norway spruce trees (Picea abies L. (Karst.)) that had been fumigated in growth chambers for weeks or months with different concentrations of SO(2), SO(2) plus ozone, or SO(2) plus NO(2). Measurements were also made on needles from older trees growing in forests in various regions of Germany with different mean annual atmospheric SO(2) emissions. In the fumigated young trees, sulfate accumulation in the needles was a linear function of atmospheric SO(2) concentration. Little or no sulfur was incorporated into the organic sulfur fraction. The mean accumulation rate of sulfate in needles of fumigated trees was about 0.4 nmol g(dw) (-1) (nl l(-1))(-1) h(-1), which is very similar to the estimated rate of uptake of atmospheric SO(2) calculated from mean stomatal conductances (15 mmol m(-2) s(-1)) and the external SO(2) concentration (the calculated rate of uptake was 0.37 nmol g(dw) (-1) (nl l(-1))(-1) h(-1)). Concentrations of organic acids and other inorganic ions did not change much in response to SO(2) fumigation. In needles collected from trees in south and southeast Germany, large differences in sulfate concentrations were observed that probably reflect SO(2) emissions in the different regions. The highest foliar sulfate concentrations, and the highest annual increase in sulfate concentration with needle age were observed in material collected from the heavily polluted Erzgebirge (up to 12 micro mol g(dw) (-1) year(-1)), followed by material from the Fichtelgebirge (up to 6 micro mol g(dw) (-1) year(-1)). If it is assumed that this annual increase is the result of uptake of SO(2) from the atmosphere, mean annual atmospheric SO(2) concentrations can be calculated. The calculated values were somewhat below the measured values in the Fichtelgebirge and in the heavily polluted Erzgebirge. Norway spruce trees can cope with high concentrations of atmospheric SO(2), provided that they can neutralize the sulfuric acid formed from SO(2). It appears that, in the field, the acid load is decreased by H(+) translocation to the roots and subsequent H(+)/K(+) exchange. However, this may be a very slow process, because it was not observed in the short-term fumigation experiments.     

竹醋液烟熏气化学成分的研究

采用固相微萃取(SPME)吸附采集竹醋液烟熏气的成分,用气相色谱—质谱联用分析鉴定,并用GC/MS总离子流色谱峰的峰面积进行归一化定量分析竹醋液烟熏气成分,鉴定出愈创木酚11.36%、苯酚10.6%、4-乙基苯酚8.23%、2-甲氧基-4-甲基苯酚7.08%、4-乙基-2-甲氧基苯酚6.6%、2-乙基苯酚5.65%、糠醛5.51%、5-甲基糖醛1.47%、乙酸1.42%、3-甲基-1-戊烯-3-醇1.42%、2,3-二甲基甲苯1.35%、2-糠酸甲酯1.35%、苯甲酸甲酯1.11%、2-甲基-2-环戊烯-1-酮1.44%、2,3-二甲基-2-环戊烯-1-酮1.31%、2-环戊烯-1-酮1.02%等74种化合物。竹醋液烟熏气的所有成分是竹醋液化学成分的特征性组成部分。     

Flavonol glycosides from Mentha lavandulacea.

In addition to kaempferol 3-O-rhamnoside-7-O-glucoside, the methanol extract of the aerial parts of Mentha lavandulacea yielded three new flavonoids identified as kaempferol 3-O-glucosyl-(1-->2)-rhamnoside-7-O-glucoside (1), kaempferol 3-O-(6"'-p-coumaroylglucosyl)-(1-->2)-rhamnoside-7-O-glucoside (2) and kaempferol 3-O-(4"'-p-coumaroylglucosyl)-(1-->2)-rhamnoside-7-O-glucoside (3).     

The effect of furanoheliangolides from Tithonia diversifolia on superoxide anion generation in human neutrophils

Four known lactones were isolated from Tithonia diversifolia: furanoheliangolides 1,3-dihydroxy-3,10-epoxy-8-(-2-methylpropanoyloxy)-germacra-11(13)-ene-6,12-olide (1), 1,3-dihydroxy-3,10-epoxy-8-(2-methylpropanoyloxy)-germacra-4,11(13)-diene-6,12-olide (2), 1,3-dimethoxy-3,10-epoxy-8-(2-methylpropanoyloxy)-germacra-4,11(13)-diene-6,12-olide (3) and, observed in natural source for the first time, furanoheliangolide 1-hydroxy-3-methoxy-3,10-epoxy-8-(2-methylpropanoyloxy)-germacra-4,11(13)-diene-6,12-olide (4). The activity of sesquiterpene lactones on superoxide anion (O(2)(o)(-)) generation from PMA-activated neutrophils was evaluated. Compound 1 did not show a full dose dependent behavior. The IC(100) was 8+/-1, 12+/-1, and 17+/-3 microM for 2 to 4, respectively.     

Two new furostanol saponins from Tribulus terrestris L.

Two new furostanol glycosides, named tribufurosides I (1) J (2), were isolated from the fruits of Tribulus terrestris L. by a combination of chemical and spectroscopic methods. Its structures were established as 26-O-β-d-glucopyranosyl-(25S)-5α-furost-12-one-2α,3β,22α,26-tetraol-3-O-β-d-glucopyranosyl (1 → 2)-β-d-glucopyranosyl (1 → 4)-β-d-galactopyranoside (1) and 26-O-β-d-glucopyranosyl-(25R)-5α-furost-20(22)-en-12-one-2α,3β,26-triol-3-O-β-d-glucopyranosyl (1 → 4)-β-d-galactopyranoside (2).     

刺槐优良无性系耐碱盐特性研究

从选定的刺槐优良无性系中选取W013,W009,C003,W038,W041等5个速生的优良无系,W037作为较差表现对比,石林作为对照进行盆栽抗盐试验。设置中性盐B1,NaCl:Na_2SO_4(1:1);碱性盐B2,NaHCO_3:Na_2CO_3(1:1);混合盐碱B3,NaCl:Na_2SO_4:NaCO_3:Na_2CO_3(1:1:1:1)3组。每组设置3个浓度梯度,Al:3g/L,A2:5g/L,A3:7g/L,分别测定其形态及生理生化指标并分析。结果表明:耐盐碱特性大小为W013,W009,C003石林刺槐W037,W038,W041,其中W013,W009,C003在7g/L仍表现出较强的耐盐碱特性。     

Two new minor cyclopeptides from Sagina japonica (Caryophyllaceae)

Two new minor cyclopeptides, named japonicin A (1), japonicin B (2), were isolated from the whole plants of Sagina japonica (Caryophyllaceae). Their structures were determined as cyclo-(Pro¹-Pro²-Leu²-Leu¹-Phe²-Pro³-Gly-Ser-Phe¹) (1) and cyclo-(Pro¹-Ile-Tyr-Asp-Pro²-Phe²-Pro³-Phe¹) (2) on the basis of spectroscopic data, especially by two-dimension NMR technologies.     

固定角规点上估测林分生长的期初特征值法

复测固定角规点时，令保留木和进界木的期初断面积分别为ｇ１和ｇ０，它们的期末断面积为ｇ２，若把断面积比（ｇ１／ｇ２）和（ｇ０／ｇ２）分别称为保留木和进界木期初断面积特征值δ１和δ０，而它们的期末特征值仍为δ＝１，则林分每公顷断面积生长量△Ｇ＝Ｆ（∑Ｚ２ｉ＝１δｉ－∑Ｚ１ｊ＝１δ１ｊ－∑Ｚ２－Ｚ１ｋ＝１δｏｋ）。当保留木和进界木的期初形高分别为ｈｆ１和ｈｆ０，它们的期末形高为ｈｆ２时，则林分每公顷的蓄积生长量△Ｍ＝Ｆ（∑Ｚ２ｉ＝１ｈｆ２ｉ－∑Ｚ１ｊ＝１（δ１ｈｆ１）ｊ－∑Ｚ２－Ｚ１ｋ＝１（δ０ｈｆ０）ｋ。期初特征值法的特点是，既能保持直接法的优点———与林分蓄积现状具有一致性，便于连续清查，又能避免其缺点———抽样效率低。能真实地反映林分生长的连续性、渐进性。模拟实验证明，期初特征值法的抽样精度为９５％左右，平均系统误差为±５％左右。抽样效率是直接法的１０—３０倍。