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.     

Insecticidal activity of Vitex mollis

Organic extracts from the leaves of Vitex mollis were assessed for their toxic effect on fall armyworm neonate larvae (Spodoptera frugiperda), an important insect pest of corn. The extracts showed insecticidal and insect growth regulatory activity, being CHCl(3)-MeOH (1:1) extract the most active, also found to be toxic in the Artemia salina test.     

Ent-trachyloban-19-oic acid isolated from Iostephane heterophylla as a promising antibacterial agent against Streptococcus mutans biofilms

From the roots of Iostephane heterophylla, six known compounds, namely, ent-trachyloban-19-oic acid (1), the mixture of ent-kaur-16-en-19-oic acid (2) and ent-beyer-15-en-19-oic acid (3), xanthorrhizol (4), 16α-hydroxy-ent-kaurane (5) and 16α-hydroxy-ent-kaur-11-en-19-oic acid (6) were isolated using a bioassay-guided fractionation method. The known compounds (1-6) were identified by comparison of their spectroscopic data with reported values in the literature. In an attempt to increase the resultant antimicrobial activity of 1 and 4, a series of reactions was performed on ent-trachyloban-19-oic acid (1) and xanthorrhizol (4), to obtain derivatives 1a, 1b, and 4a-4d. All the isolated compounds (1-6) and the derivatives 1a, 1b, and 4a-4d were evaluated for their antimicrobial activity against two oral pathogens, Streptococcus mutans and Porphyromonas gingivalis associated with caries and periodontal disease, respectively. Compounds 1, 1b, 2+3, 4 and 4d inhibited the growth of S. mutans with concentrations ranging from 4.1 μg/mL to 70.5 μg/mL. No significant activity was found on P. gingivalis except for 4 with an MIC of 6.8 μg/mL. The ability of 1, 1b, 2+3, 4 and 4d to inhibit biofilm formation by S. mutans was evaluated. It was found that 1, 1b, 4 and 4d interfered with the establishment of S. mutans biofilms, inhibiting their development at 32.5, 125.0, 14.1 and 24.4 μg/mL, respectively.     

Forest thinning and subsequent bark beetle-caused mortality in Northeastern California

The Warner Mountains of northeastern California on the Modoc National Forest experienced a high incidence of tree mortality (2001–2007) that was associated with drought and bark beetle (Coleoptera: Curculionidae, Scolytinae) attack. Various silvicultural thinning treatments were implemented prior to this period of tree mortality to reduce stand density and increase residual tree growth and vigor. Our study: (1) compared bark beetle-caused conifer mortality in forested areas thinned from 1985 to 1998 to similar, non-thinned areas and (2) identified site, stand and individual tree characteristics associated with conifer mortality. We sampled ponderosa pine (Pinus ponderosa var ponderosa Dougl. ex Laws.) and Jeffrey pine (Pinus jeffreyi Grev. and Balf.) trees in pre-commercially thinned and non-thinned plantations and ponderosa pine and white fir (Abies concolor var lowiana Gordon) in mixed conifer forests that were commercially thinned, salvage-thinned, and non-thinned. Clusters of five plots (1/50th ha) and four transects (20.1 × 100.6 m) were sampled to estimate stand, site and tree mortality characteristics. A total of 20 pre-commercially thinned and 13 non-thinned plantation plot clusters as well as 20 commercially thinned, 20 salvage-thinned and 20 non-thinned mixed conifer plot clusters were established. Plantation and mixed conifer data were analyzed separately. In ponderosa pine plantations, mountain pine beetle (Dendroctonus ponderosae Hopkins) (MPB) caused greater density of mortality (trees ha⁻¹ killed) in non-thinned (median 16.1 trees ha⁻¹) compared to the pre-commercially thinned (1.2 trees ha⁻¹) stands. Percent mortality (trees ha⁻¹ killed/trees ha⁻¹ host available) was less in the pre-commercially thinned (median 0.5%) compared to the non-thinned (5.0%) plantation stands. In mixed conifer areas, fir engraver beetles (Scolytus ventralis LeConte) (FEN) caused greater density of white fir mortality in non-thinned (least square mean 44.5 trees ha⁻¹) compared to the commercially thinned (23.8 trees ha⁻¹) and salvage-thinned stands (16.4 trees ha⁻¹). Percent mortality did not differ between commercially thinned (least square mean 12.6%), salvage-thinned (11.0%), and non-thinned (13.1%) mixed conifer stands. Thus, FEN-caused mortality occurred in direct proportion to the density of available white fir. In plantations, density of MPB-caused mortality was associated with treatment and tree density of all species. In mixed conifer areas, density of FEN-caused mortality had a positive association with white fir density and a curvilinear association with elevation.     

A new coumarin from Sarcandra glabra

Sarcandracoumarin (1), the first coumarin having a 1-phenylethyl substituent at the C-3 position, was isolated along with eleven known phenolic compounds from the water extract of Sarcandra glabra. Its structure was elucidated on the basis of spectroscopic data. Compound 1 exhibited moderate or weak cytotoxicity against several tumor cell lines.     

A new triterpenoidal ester from Celastrus rosthornianus

3-O-Palmitate of 1beta, 3beta, 11beta-trihydroxy-olean-12-ene (1),was isolated from the stalks of Celastrus rosthornianus. The structure was elucidated by MS, 1D- and 2D-NMR experiments as well as by chemical degradation.     

Chemical constituents of Roldana lineolata

The new eremophilanolide 1, the known eremophilane derivatives 2 and 3, already described as part of mixtures, the known compounds hyperin, 2'-acetylhyperin and two calenduladiol esters were isolated from Roldana lineolata. Their structures were determined by spectroscopic methods. Compounds 1 and 2 as well as their acetylated and oxidized derivatives were tested against several fungi strains. Eremophilanolide 1 showed a mild activity against Trichophyton mentagrophytes.     

Anti-HBV activities of Streblus asper and constituents of its roots

The extracts from leaves, heartwood, barks and roots of the Streblus asper were investigated for anti-HBV activities, separately. The results suggested that the MeOH extracts of the heartwood, barks, and roots exhibited good anti-HBV activities. Further investigations displayed that ethyl acetate and n-butanol soluble parts of their MeOH extracts showed more significant anti-HBV activities. Moreover, a new lignan, together with 11 known compounds, was isolated from n-butanol-soluble part of MeOH extract of the roots of S. asper. The structures were elucidated by spectroscopic methods, including 1D NMR ((1)H NMR, (13)C NMR), 2D NMR (HMQC, HMBC) and HR-EI-MS experiments. Compounds 1-3 were evaluated for their anti-HBV activities. Honokiol showed significant anti-HBV activity with IC(50) values of 3.14μM and 4.74μM for HBsAg and HBeAg with no cytotoxicity respectively, while lamivudine (3TC, positive control) exhibited weak anti-HBV activity with IC(50) values of 11.81μM and 25.80μM for HBsAg and HBeAg respectively.     

A new cerebroside from Polygala japonica

The isolation of a new cerebroside, 1-O-beta-d-glucopyranosyl-(2S,3S,4R,11E)-2-[(2'R)-2'-hydroxypalmitoylamino]-11-octadecene-1,3,4-triol (polygalacerebroside) (1), from the aerial part of Polygala japonica is reported.     

银杏过氧化氢酶基因CAT1的克隆及表达分析

利用RACE技术从银杏中克隆到过氧化氢酶基因(GbCAT1)的cDNA全长。进化树分析结果表明:GbCAT1和其他物种的CAT源自于相同的祖先。Southern杂交显示:GbCAT1属于1个小的多基因家族。实时定量RT-PCR分析表明:GbCAT1在银杏的根、茎、叶和果中都有表达,在叶中的相对表达量最高,其次为果、茎和根。GbCAT1的转录受到ABA、渗透压、紫外、低温和高温胁迫的诱导。水杨酸处理下,GbCAT1相对表达量迅速降低。CAT1基因在逆境条件下的相对表达变化与环境胁迫有关。     

猴头菌锰过氧化物酶1基因在构巢曲霉的异源转化与表达

为提高猴头菌菌株CB1锰过氧化物酶(MnP)基因的表达产量,采用PEG/CaCl2介导的原生质体转化方法,将携带有He-mnp1的重组质粒pLB01/He-mnp1转入到构巢曲霉尿嘧啶尿苷营养缺陷菌株TN02A7的原生质体中,获得了转化子菌株TN02A7-He-mnp1,并在乙醇脱氢酶启动子alcA(p)控制下实现了异源表达。将TN02A7-He-mnp1、TN02A7、构巢曲霉野生型菌株WJA01、猴头菌菌株CB1在相同的木质素环境下进行培养并检测MnP酶活性,结果表明:转化子菌株TN02A7-He-mnp1在0.05 g.L-1血红素的情况下、诱导96 h后酶活性最高为38.31 U.L-1,比不添加血红素的酶活力高8.64倍,但比猴头菌菌株CB1的酶活力低,而TN02A7与WJA01始终无MnP酶活性,说明基因He-mnp1已经成功地被转化到TN02A7-He-mnp1中,并在木质素环境下得到表达,血红素是重组MnP基因异源表达的限制性因素之一。本文为生产MnP和提高MnP产量提供了新的途径。     

宽叶杜香叶柄再生体系建立及种质离体保存研究

The tender leafstalks of Ledum palustre var.dilatatum were used as explants for the experiment.Uniform design for the most suitable media for shoots regeneration immediately at base of tender leafstalks,rooting and germplasm conservation in vitro was screened.The results showed that N6+ZT 2.65 mg·L-1+IAA 0.05 mg·L-1 was fits for shoots regeneration,the frequency of shoots induction was higher than 92.5%;MS(modified)+IAA 0.1 mg·L-1+Kt 0.75 mg·L-1 for rooting,the rate of rooting was 98%;N-68+B9 2.5 mg·L-1+ Ph...     

Development of ITS sequence based molecular marker to distinguish, Tribulus terrestris L. (Zygophyllaceae) from its adulterants

Tribulus terrestris L. (Zygophyllaceae) is one of the highly traded raw drugs and also used as a stimulative food additive in Europe and USA. While, Ayurvedic Pharmacopoeia of India recognizes T. terrestris as Goksura, Tribulus lanuginosus and T. subramanyamii are also traded by the same name raising issues of quality control. The nuclear ribosomal RNA genes and ITS (internal transcribed spacer) sequence were used to develop species-specific DNA markers. The species-specific markers efficiently amplified 295 bp for T. terrestris (TT1F and TT1R), 300 bp for T. lanuginosus (TL1F and TL1R) and 214 bp for T. subramanyamii (TS1F and TS1R). These DNA markers can be used to distinguish T. terrestris from its adulterants.     

杨树生物钟节律基因PtCCA1的克隆及表达模式研究

生物钟节律基因CCA1在植物的光周期反应中起着重要的调控作用.利用RT-PCR方法克隆获得了一条包含1902 bp开放阅读框的杨树CCA1基因cDNA序列,其编码633个氨基酸残基,蛋白的分子量约为68.90 kDa,等电点为6.33.分析显示含有1个Myb-like DNA结合域及2个蛋白跨膜结合域.实时荧光定量PCR分析发现,PtCCA1基因主要在杨树叶组织中表达;随着光照时间的变化,该基因在杨树中的表达量呈现白昼不断降低而夜晚逐渐升高的昼夜变化趋势.研究结果为进一步探索PtCCA1基因在调控杨树光周期响应途径中的功能以及杨树光周期敏感机制提供了科学基础.     

日本落叶松体细胞胚胎发生相关基因LaSERK1的克隆与表达分析

本研究克隆了日本落叶松体细胞胚胎发生相关受体类蛋白激酶基因 LaSERK1,并检测了在不同培养条件下LaSERK1的表达情况,发现LaSERK1与已发现的其他物种SERK1 基因有高度相似性,qRT-PCR结果显示： LaSERK1在体胚发生早期高表达。结果表明：LaSERK1可能在落叶松体胚发育早期起重要作用,LaSERK1 也可能成为早期胚性细胞的标记基因。     

Anti-neuroinflammatory constituents from Polygala tricornis Gagnep

Two new compounds (S)-(+)-butyl-4-methylene-5-oxo-pyrrolidin-2-carboxylate (1) and (5-formylfuran-2-yl)methyl 4-hydroxy-2-methylenebutanoate (2), together with four known compounds (3-6) were isolated from the roots of Polygala tricornis Gagnep. Their structures were determined on the basis of 1D- and 2D-NMR experiments and by comparison with physical data of known compounds. All the isolated compounds were examined for their inhibitory effect on the nitric oxide (NO) production induced by lipopolysaccharide (LPS) in BV-2 microglial cells, and compounds 1 and 2 exhibited pronounced inhibition on the NO production with IC(50) values of 14.1 μM and 1.77 μM, respectively.     

Enrichment planting as a silvicultural option in the eastern Amazon: Case study of Fazenda Cauaxi

Liana-dominated forest patches constitute 15–20% of old-growth forests in the Eastern Amazon but are generally excluded from management for timber production. Here we ask if liana-dominated patches may be brought into production by clearing lianas and conducting enrichment planting (EP) of native timber species. We present growth results from 8 years of such EP trials. Rapid growth and low mortality of all species in this study suggest that EP in cleared liana patches can contribute to timber stocks in second and third harvests of managed forests. The most vigorous individuals of Parkiagigantocarpa and Schizolobium amazonicum in each enrichment site grew more than 1 cm diameter per year (rates were initially >2 cm yr⁻¹), and attained dominant canopy positions and diameters equal to those of small canopy trees in the surrounding forest within 8 years of planting (mean dbh ∼18 cm and ∼20 cm, respectively, at year 8). Limited data on Ceiba pentandra plantings indicate a similar trajectory for this species (dbh ∼40 cm in 8 years). The most vigorous Swietenia macrophylla grew at least 1 cm per year in enrichment plots (mean dbh ∼10 cm in 8 years), but take longer to attain dominant positions. Tabebuia serratifolia may take much longer to reach the canopy than other species tested (rates <1 m yr⁻¹). We attribute the excellent performance to light availability; planting in intact soil with minimal compaction and abundant organic material; and low competition rates maintained by periodic thinning of competing vegetation.     

Asterosaponins from the starfish Culcita novaeguineae and their bioactivities

Bioassay-guided fractionation of the n-BuOH extract of the starfish Culcita novaeguineae resulted in the isolation of one new sulfated steroidal glycoside (asterosaponin) (1), along with three known asterosaponins, thornasteroside A (2), marthasteroside A(1) (3) and regularoside A (4), as active compounds causing morphological abnormality of Pyricularia oryzae mycelia. Their structures were elucidated by extensive spectral studies and chemical evidences. All the saponins showed moderate cytotoxicity against cancer cell lines K-562 and BEL-7402.     

长白山区珍稀濒危植物野生玫瑰植株再生体系的建立

玫瑰(Rosa rugosa Thunb.)又称玫瑰花,是蔷薇科 (Rosaceae) 蔷薇属(Rosa L.)落叶灌木.该种为国家三级重点保护植物.<中国珍稀濒危保护植物名录(第一册)>中定为濒危种,<中国物种红色名录>定为易危种[1],<吉林省野生动植物保护管理暂行条例>中定其为省级一类重点保护植物.是待开发的野生珍稀濒危药用植物,花、果、根入药,主治吐血、痛经、咯血、乳痈、月经不调等症.该种玫瑰具有喜光,耐寒,耐贫瘠,抗风等特性,可防止高山苔原带的水土流失,对维护生态平衡,美化天池环境以及引种驯化、开发利用于作护坡保土、园林绿化和培育玫瑰新品种;对研究该属植物的系统发育与地理分布也有重要科学价值.玫瑰在长白山区数量非常稀少,仅在珲春市敬信乡有零星分布.近年来,由于旅游设施及道路的修建等人为因素的干扰,其生境遭到严重破坏.又因玫瑰的天然更新能力非常弱,其种子成熟度小,种子繁殖可操作性极差,插条繁殖生根率和移栽成活率也极低,使其开发及利用受到极大限制.因此,在保护好现有野生资源的同时,本研究以玫瑰新生嫩茎为外植体,利用植物组织培养方法,采用均匀设计法,以期筛选出玫瑰嫩茎离体培养各阶段的培养基.目前,与其同属的其他种植物的离体培养已有报道,但关于该种玫瑰植株再生体系的研究迄今未见.     

Amides with anti-platelet aggregation activity from Piper taiwanense

Three new amides, taiwanamides A-C (1-3), and two known amides, 1-cinnamoylpyrrolidine (4) and 1-(m-methoxycinnamoyl)pyrrolide (5), have been isolated from the stem of Piper taiwanense. The structures of the new amides were determined by spectral analyses. These five amides exhibited inhibitory activity of platelet aggregation in vitro. Taiwanamide C (3) owned the most potent inhibition activity of platelet aggregation induced by collagen showing IC(50) value as 8.9 microM. Taiwanamide B (2) and 1-(m-methoxycinnamoyl)pyrrolide (5) exhibited IC(50) values of 17.3 and 17.4 microM, respectively.