Anti-staphylococcal activity of C-methyl flavanones from propolis of Australian stingless bees (Tetragonula carbonaria) and fruit resins of Corymbia torelliana (Myrtaceae)

Propolis of Australian stingless bees (Tetragonula carbonaria, Meliponini) originating from Corymbia torelliana (Myrtaceae) fruit resins was tested for its antimicrobial activities as well as its flavonoid contents. This study aimed at the isolation, structural elucidation and antibacterial testing of flavanones of C. torelliana fruit resins that are incorporated into stingless bee propolis. Flavanones of this study were elucidated by spectroscopic and spectrometric methods including UV, 1D and 2D NMR, EI-MS, ESI-MS and HR-MS. The results indicated known C-methylated flavanones namely, 1 (2S)-cryptostrobin, its regioisomer 2 (2S)- stroboponin, 3 (2S)- cryptostrobin 7-methyl ether, and 6 (2S)- desmethoxymatteucinol, and known flavanones 4 (2S)- pinostrobin and 5 (2S)- pinocembrin as markers for C. torelliana fruit resins and one propolis type. Ethanolic preparations of propolis were shown to be active against Staphylococcus aureus (ATCC 25923) and to a lesser extent against Pseudomonas aeruginosa (ATCC 27853). C. torelliana flavanones inhibited the growth of S. aureus therefore contributing to the antibacterial effects observed for Australian stingless bee propolis extracts.     

Sesquiterpene lactones from Sonchus arvensis L. and their antibacterial activity against Streptococcus mutans ATCC 25175

Two new sesquiterpene lactones, 1β-sulfate-5α, 6βH-eudesma-3-en-12, 6α-olide (1) and 1β-(p-hydroxyphenyl acetyl)-15-O-β-d-glucopyranosyl-5α, 6βH-eudesma-3-en-12, 6α-olide (2) were isolated from Sonchus arvensis L. (Asteraceae), together with eight known compounds. Their structures were elucidated through spectroscopic and chemical methods. They were evaluated for antibacterial activity. Among them, compounds 1 and 7 exhibited antibacterial activity against oral pathogen Streptococcus mutans ATCC 25175 with MIC values of 15.6 and 62.5 µg/ml, respectively.     

Effect of Beauveria bassiana and Metarhizium anisopliae on the Trialeurodes vaporariorum-Encarsia formosa system

The virulence of three strains of Beauveria bassiana and one of Metarhizium anisopliae was tested against Trialeurodes vaporariorum and its parasitoid Encarsia formosa in laboratory assays. These strains were previously selected for their virulence against Galleria mellonella and Tenebrio molitor. The commercial B. bassiana strain ATCC 74040, both as pure fungal culture and formulated myco-insecticide (Naturalis), was included in the assays as positive control. First, the entomopathogenic fungal strains were tested for their virulence against T. vaporariorum nymphs on tomato leaf disks. Then, the E. formosa development was evaluated under treatment with the entomopathogenic fungal strains at five different time points from the parasitization of T. vaporariorum nymphs. The virulence of our entomopathogenic fungal strains was superior to that of ATCC 74040, although not significantly, resulting in a cumulative mortality (CM) of T. vaporariorum nymphs 7 days after inoculation (DAI) greater than 86 %. Our M. anisopliae strain CIST8 was the most effective (96.6 % CM 7 DAI), even superior to the myco-insecticide Naturalis (94.2 %), which was more effective than the ATCC 74040 pure strain (85.6 %). The entomopathogenic fungal strains, and especially Naturalis, negatively affected E. formosa development and its parasitization activity of T. vaporariorum nymphs. This effect was more pronounced when the fungal strains were applied before parasitization. Results suggest that the application of entomopathogenic fungi is incompatible with E. formosa release on crops.     

Antibacterial tetraoxygenated xanthones from the immature fruits of Garcinia cowa

A phytochemical investigation of the acetone extract from the immature fruits of Garcinia cowa led to the isolation of two novel tetraoxygenated xanthones, garcicowanones A (1) and B (2), together with eight known tetraoxygeanted xanthones. Their structures were determined by spectroscopic analysis. All isolated compounds were evaluated for their antibacterial activity against Bacillus cereus TISTR 688, Bacillus subtilis TISTR 008, Micrococcus luteus TISTR 884, Staphylococcus aureus TISTR 1466, Escherichia coli TISTR 780, Pseudomonas aeruginosa TISTR 781, Salmonella typhimurium TISTR 292 and Staphylococcus epidermidis ATCC 12228. α-Mangostin showed potent activity (MIC 0.25–1 μg/mL) against three Gram–positive strains and garcicowanone A and β-mangostin exhibited strong antibacterial activity against B. cereus with the same MIC values of 0.25 μg/mL.     

Lignan formation in hairy root cultures of Edelweiss (Leontopodium nivale ssp. alpinum (Cass.) Greuter)

A hairy root line of Edelweiss (Leontopodium nivale ssp. alpinum (Cass.) Greuter) was obtained upon transformation with Agrobacterium rhizogenes strain ATCC15834. Elicitation of this line with silver nitrate, sucrose, methyl jasmonate and yeast extract at various concentrations in most cases resulted in a stimulation of lignan biosynthesis. Through elicitation with 6% sucrose the roots accumulated the pharmacologically active lignans leoligin and 5-methoxy-leoligin at levels of 0.0678% and 0.0372%, respectively, without significant growth inhibition. These lignan levels were comparable to those found in intact roots of cultivated Edelweiss. The biotechnological production of leoligin could be an attractive option for the continuous, field culture-independent production of the valuable secondary metabolites leoligin and 5-methoxy-leoligin.     

Mangostanaxanthones I and II,new xanthones from the pericarp of Garcinia mangostana

Two new xanthones: mangostanaxanthones I (3) and II (5) were isolated from the pericarp of Garcinia mangostana, along with four known xanthones: 9-hydroxycalabaxanthone (1), parvifolixanthone C (2), α-mangostin (4), and rubraxanthone (6). Their structures were elucidated on the basis of IR, UV, 1D, 2D NMR, and MS spectroscopic data, in addition to comparison with literature data. The isolated compounds were evaluated for their antioxidant, antimicrobial, and quorum-sensing inhibitory activities. Compounds 3 and 5 displayed promising antioxidant activity with IC₅₀ 12.07 and 14.12 μM, respectively using DPPH assay. Compounds 4–6 had weak to moderate activity against Escherichia coli and Staphylococcus aureus, while demonstrated promising action against Bacillus cereus with MICs 0.25, 1.0, and 1.0 mg/mL, respectively. The tested compounds were inactive against Candida albicans. However, they showed selective antifungal potential toward Aspergillus fumigatus. Compounds 3 and 4 possessed quorum-sensing inhibitory activity against Chromobacterium violaceum ATCC 12472.     

Ethanol production from sugi pulp under simultaneous saccharification and fermentation using a cocktail enzyme of T. reesei and A. tubingensis produced by solid-state fermentation

The process of solid-state fermentation was used to produce a cocktail enzyme of Trichoderma reesei ATCC 66587 and Aspergillus tubingensis KRCF 700-33. Wheat bran, corncob, and sugi pulp were supplemented with ammonium sulfate as an enzyme-producing medium using T. reesei and A. tubingensis. The corncob blend ratio, duration of incubation, and ammonium sulfate concentration were optimized for enhancing cellulase production from T. reesei using a Box-Behnken design. Filter paper degrading activity more than tripled when T. reesei was grown in the optimized medium, as compared with the initial medium. The highest activity of 4.03 FPU/ml (about 29 FPU/g of dry material) was obtained with a cocktail enzyme having a 25 % content of A. tubingensis and 75 % of T. reesei. The sugi pulp was then fermented to ethanol with the cocktail enzyme and thermotolerant yeast (Saccharomyces cerevisiae BA-11) under simultaneous saccharification and fermentation (SSF) at 40 °C. An ethanol concentration of 4.48 % (w/v) was achieved using the cocktail enzyme (4 FPU/g-pulp) that was produced on-site with a substrate loading level of 12.5 wt %, which achieved an ethanol yield of 76 % after 72 h.     

Structure elucidation of two triterpenoid saponins from rhizome of Anemone raddeana Regel

Two new 27-hydroxy-oleanolic acid type triterpenoid saponins, raddeanoside 20 (1) and raddeanoside 21(2) were isolated from the rhizome of Anemone raddeana Regel. The structures of the two compounds were elucidated as 27-hydroxy-oleanolic acid 3-O-α-l-rhamnopyranosyl(1→2) [β-d-glucopyranosyl (1→4)]-α-l-arabinopyranoside (1) and 3-O-α-l-rhamnopyranosyl (1→2)-α-l-arabinopyranosyl-27-hydroxy-oleanolic acid 28-O-α-l-rhamnopyranosyl(1→4)-β-d-glucopyranosyl (1→6)-β-d-glucopyranoside (2) on the basis of chemical and spectral evidence.     

毛竹TIPs基因家族成员组织表达模式研究

[目的]通过研究毛竹TIPs的分子特征和表达模式,为揭示逆境胁迫条件下TIPs在竹子中的作用提供证据,为培育抗逆的植物新品种提供新的基因资源。[方法]以毛竹为对象,利用生物信息学方法对毛竹基因组中的TIPs基因进行了全面分析,采用实时荧光定量PCR技术分析基因在不同组织及干旱、水淹和Na Cl胁迫下的表达模式。[结果]毛竹基因组中含有6个TIPs同源基因,分别隶属于3个亚类(TIP1、TIP2和TIP4)。基因结构预测显示,Pe TIP1;1、Pe TIP1;2、Pe TIP2;2和Pe TIP4;2由2个外显子和1个内含子组成,而Pe TIP2;1和Pe TIP4;1由3个外显子和2个内含子组成。蛋白结构分析显示,毛竹6个TIPs均具有2个典型的NPA结构域和4个ar/R模体。通过转录组数据分析基因的组织表达特异性,结果表明Pe TIP1;1在各组织中的表达丰度均较高;Pe TIP1;2主要在花中表达;Pe TIP2;1在根和鞭中表达量较高;Pe TIP2;2在根中特异表达;Pe TIP4;1在叶片中表达丰度最高;Pe TIP4;2在笋和鞭中表达水平较高,在根中最低。实时定量PCR结果分析证明,干旱处理后毛竹根中Pe TIP4;1的表达量显著升高(p0.01),Pe TIP2;1、Pe TIP2;2和Pe TIP4;2表达受到抑制(p0.01);水淹处理后根中Pe TIP1;1和Pe TIP4;1表达量显著增加(p0.01),Pe TIP1;2、Pe TIP2;2、和Pe TIP4;2则显著降低(p0.01);Na Cl处理后根中6个Pe TIPs的表达量均显著增加(p0.01)。干旱处理后毛竹叶片中Pe TIP1;1、Pe TIP1;2和Pe TIP4;1表达量均显著增加(p0.01);水淹处理后叶片中Pe TIPs表达量均显著提高(p0.01);Na Cl处理后叶片中Pe TIP2;1表达受到明显抑制(p0.01)。[结论]Pe TIPs可能在毛竹抵抗干旱、水淹和Na Cl等非生物胁迫中发挥着不同程度的作用。     

Three new germacrane-type sesquiterpene stereoisomers from the flowers of Chrysanthemum indicum

From the flowers of Chrysanthemum indicum, three new germacrane-type sesquiterpene stereoisomers (1β,3α,5β-trihydroxyl-7-isopropenyl-germacren-4(15), 10(14)-diene (1), 1β,3β,5α-trihydroxyl-7-isopropenyl-germacren-4(15), 10(14)-diene (2), 1β,3β,5β-trihydroxyl-7-isopropenyl-germacren-4(15), 10(14)-diene (3)) were isolated, whose structures were elucidated on the basis of extensive spectroscopic analysis. The absolute configuration of compound 1 was determined by a single crystal X-ray diffraction study using a mirror Cu Kα radiation.     

Two new triterpene saponins from the aerial parts of Paraquilegia microphylla

Two new triterpene saponins, paraquinosides A (1) and B (2) were isolated from the aerial parts of Paraquilegia microphylla (Royle) Dromm. et Hutch, a Tibetan ethnic medicine distributed in the Qinghai–Tibet Plateau. On the basis of 1D and 2D NMR evidence, their structure was elucidated as 3-O-α-L-rhamnopyranosyl (1→2)-β-D-glucopyranosyl-15-dehydroxyl-16-O-methyl-24, 25-deoxy-26-hydroxylshengmanol-26-O-β-D-glucopyranoside (1) and 3-O-α-L-Rhamnopyranosyl (1→2)-[β-D-glucopyranosyl(1→3)]-β-D-glucopyranosyl-15-dehydroxyl-16-O-methyl-24, 25-deoxy-26-hydroxylshengmanol-26-O-β-D- glucopyranoside (2), respectively.     

Cytotoxic ceramides and glycerides from the roots of Livistona chinensis

A 70% ethanol extract of the roots of Livistona chinensis has been investigated, led to the isolation of 13 compounds, including a new ceramide, (2S,3S,4R,9Z)-2-[(2R)-2-hydroxytricosanoylamino]-9-octadecene-1,3,4-triol (2), a new glycosyl ceramide, 1-O-β-d-glucopyranosyl-(2S,3S,4R,9Z)-2-[(2R)-2-hydroxydocosanoylamino]-9-octadecene-1,3,4-triol (3), three new monoacylglycerols, 1-(34-hydroxytetratriacontanoyl)-sn-glycerol (9), 1-[nonadeca-(9Z,12Z)-dienoyl]-sn-glycerol (10), and 1-[12-hydroxypentatriaconta-(13E,15Z)-dienoyl]-sn-glycerol (11), a new diacylglycerol, 1-(heptadeca-6Z,9Z-dienoyl)-3-(octadeca-6Z,9Z,12Z-trienoyl)-sn-glycerol (12), as well as a new diacylglycerol aminoglycoside, 1-octadecanoyl-2-nonadecanoyl-3-O-(6-amino-6-deoxy)-β-d-glucopyranosyl-sn-glycerol (13). The structures of new compounds were elucidated, based on spectroscopic, zymologic and chemical methods. Among the compounds tested, compounds 3, 4 and 13 showed significantly antiproliferative effects against the human tumor cell lines (K562, HL-60, HepG2, and CNE-1) with the IC₅₀ of 10–65 μM. To our knowledge, this is first report of the occurrence of ceramides and acylglycerols in the genus Livistona.     

Sibiricasaponins A–E,five new triterpenoid saponins from the aerial parts of Polygala sibirica L.

Five new triterpenoid saponins, named as sibiricasaponins A–E (1–5), were isolated and identified from the aerial parts of Polygala sibirica L., together with nine known triterpenoid saponins (6–14). The chemical structures of the five new triterpenoid saponins (1–5) were elucidated as 3β,19α-dihydroxyurso-12-ene-23,28-dioic acid 3-O-β-d-glucuronopyranoside (1), pomolic acid 3-O-(3-O-sulfo)-α-l-arabinopyranoside (2), pomolic acid 3-O-(4-O-sulfo)-β-d-xylopyranoside (3), pomolic acid 3-O-(2-O-acetyl-3-O-sulfo)-α-l-arabinopyranoside (4), and 3-O-β-d-glucopyranosyl medicagenic acid 28-O-β-d-galactopyranosyl (1 → 4)-β-d-xylopyranosyl (1 → 4)-α-l-rhamnopyranosyl (1 → 2)-(4-O-acetyl)-[β-d-apiofuranosyl (1 → 3)]-β-d-fucopyranosyl ester (5), respectively, on the basis of spectroscopic data and physicochemical evidences. These isolated compounds (1–14) were evaluated for their anti-ischemic effects on oxygen/glucose deprivation (OGD) model in vitro, and only compound 7 showed a weak anti-ischemia effect, with EC₅₀ value of 46.7 μM.     

Noreudesmane sesquiterpenoids from the leaves of Nicotiana tabacum

Six new 14-noreudesmane sesquiterpenoids, nicotabacosides A–F (1–6), along with five known sesquiterpenoids (7–11), were isolated from the leaves of Nicotiana tabacum. The structures of compounds 1–6 were elucidated as isorishitin 3-O-β-d-glucopyranoside (1), rishitin 3-O-β-d-glucopyranoside (2), rishitin 2-O-β-d-glucopyranoside (3), 1, 6-dehydro-rishitin 3-O-β-d-glucopyranoside (4), 2-hydroxyl-ligudentatol 3-O-β-d-glucopyranoside (5) and oxyglutinosone 3-O-β-d-glucopyranoside (6) based on extensive spectroscopic analyses (HRESIMS, UV, IR, 1D and 2D NMR). Their absolute configurations were determined by X-ray single-crystal diffraction and comparison of their electronic circular dichroism (ECD) spectra.     

New cytotoxic triterpenoid saponins from the whole plant of Clematis lasiandra Maxim

Four new oleanane type triterpenoid saponins (1–4) and three known saponins (5–7) were isolated from the whole plant of Clematis lasiandra Maxim. The structures of the four new compounds were elucidated as 3-O-β-d-ribopyranosyl-(1 → 3)-α-l-rhamnopyranosyl-(1 → 2)-[β-d-glucopyranosyl-(1 → 4)]-β-d-xylopyranosyl hederagenin (1), 3-O-β-d-ribopyranosyl-(1 → 3)-α-l-rhamnopyranosyl-(1 → 2)-β-d-xylopyranosyl oleanolic acid 28-O-β-d-glucopyranosyl ester (2), 3-O-β-d-ribopyranosyl-(1 → 3)-α-l-rhamnopyranosyl-(1 → 2)-β-d-xylopyranosyl hederagenin (3) and 3-O-β-d-ribopyranosyl-(1 → 3)-α-l-rhamnopyranosyl-(1 → 2)-[β-d-glucopyranosyl-(1 → 4)]-α-l-arabinopyranosyl hederagenin (4) on the basis of extensive spectroscopic analysis and chemical evidence. Compounds 1–7 were evaluated for their cytotoxicity against human tumor cell lines HL-60, Hep-G2 and SGC-7901, and all of the evaluated saponins showed significant cytotoxicity to those three tumor cell lines with IC₅₀ in the range from 1.40 to 19.50 μmol/L except for compounds 2 and 6.     

New triterpene saponins from the root of Ilex pubescens

Two new triterpene glycosides named ilexpublesnin A (1) and ilexpublesnin B (2) were isolated from the root of Ilex pubescens. Their structures were determined as 3-O-(β-d-xylopyranosyl)-28-O-(β-d-glucopyranosyl)-3β, 19α-dihydroxyurs-23-oxo-12-en-28-oic acid (1) and 28-O-(β-d-xylopyranosyl-(2 → 1)-β-d-glucopyranosyl)-3β, 19α-dihydroxyurs-23-oxo-12-en-28-oic acid (2) on the basis of chemical and spectroscopic methods.     

New bibenzyl glycosides from leaves of Camellia oleifera Abel. with cytotoxic activities

Studies on the chemical constituents of leaves of Camellia oleifera Abel. led to the isolation of 3 new bibenzyl glycosides. Their structures have been elucidated as 1-(3′,5′-dihydroxy)phenyl-2-(4″-O-β-D-glucopyranosyl)phenylethane (1), 1-(3′,5′-dimethoxy)phenyl-2-(4″-O-β-D-glucopyranosyl)phenylethane (2) and 1-(3′,5′-dimethoxy)phenyl-2-[4″-O-β-D-glucopyranosyl(6→1)-O-α-L-rhamnopyranosyl]phenylethane (3) through spectral studies including HR-ESI-MS, ¹H NMR, ¹³C NMR and 2D NMR experiments. All the above 3 bibenzyl glycosides showed cytotoxic activities to Hela and hep2 cell lines.     

版纳龙竹CONSTANS同源基因的克隆与序列分析

以版纳龙竹基因组DNA为模板,采用前人基于水稻CO同源基因Hd1序列的保守区所设计的特异引物COS1和COA1,运用PCR方法扩增出一条1 520 bp的DNA片段,并克隆到pGEM-T载体。测序和序列分析结果显示:该片段含有1个590 bp的内含子,编码区930 bp共编码310个氨基酸;该基因被命名为DxCO1,其DNA序列在G enB ank中的注册号为GQ358925。在G enB ank中进行同源性检索的结果显示:其核苷酸序列与其它禾本科植物CO同源基因的氨基酸序列同源性高达81%~91%;推测的DxCO1蛋白质序列与其它种子植物CO同源基因蛋白质序列的系统发育分析结果显示:DxCO1与小麦Hd1-like等5个基因聚成了一个强烈支持的分支;另外,在该片段推测的蛋白质序列的氨基端含有一个类似锌指蛋白的B-box(Cx2Cx8Cx7Cx2Cx4Hx8H)结构域,羧基端含有一个CCT(CO,CO-like,TOC1)结构域。序列和结构的高度同源性表明:DxCO1是版纳龙竹的1个CO-like基因,可能对其开花调控有着重要作用。     

A new steroidal saponin from the dried stems of Asparagus officinalis L

Yamogenin II (1), a new steroidal saponin with a unique aglycone moiety, and (25S)-spirostan-5-ene-3β-ol-3-O-α-l-rhamnopyranosyl-(1,2)-[α-l-rhamnopyranosyl-(1,4)]-β-d-glucopyranoside (2), were isolated from the dried stems of Asparagus officinalis L. The structure of 1 was assessed by spectroscopial analysis as (25S)-spirostan-5-ene-3β,21-diol-3-O-α-l-rhamnopyranosyl-(1,2)-[α-l-rhamnopyranosyl-(1,4)]-β-d-glucopyranoside.     

New antioxidant and antiglycation active triterpenoid saponins from the root bark of Aralia taibaiensis

Four new oleanane type triterpenoid saponins (1-4) and a known saponin (5) were isolated from the root bark of Aralia taibaiensis Z.Z. Wang et H.C. Zheng. The structures of the four new compounds were elucidated as 3-O-{β-d-glucopyranosyl-(1 → 2)-[β-d-glucopyranosyl-(1 → 3)]-β-d-glucurono-pyranosyl}-olean-11,13(18)-diene-28-oic acid 28-O-β-d-glucopyranosyl ester (1), 3-O-{β-d-gluco-pyranosyl-(1 → 3)-[α-l-arabinofuranosyl-(1 → 4)]-β-d-glucuronopyranosyl}-olean-11,13(18)-diene-28-oic acid 28-O-β-D-glucopyranosyl ester (2), 3-O-{β-d-glucopyranosyl-(1 → 2)-[α-l-arabinofuranosyl-(1 → 4)]-β-d-glucuronopyranosyl}-oleanolic acid 28-O-β-D-glucopyranosyl ester (3) and 3-O-{β-d-glucopyranosyl-(1 → 2)-[β-d-glucopyranosyl-(1 → 3)]-β-d-glucuronopyranosyl}-oleanolic acid 28-O-β-d-glucopyranosyl ester (4), on the basis of extensive spectral analysis and chemical evidence. Compounds 1-5 exhibited moderate effects on antioxidant and antiglycation activities, which correlated with treatment of diabetes mellitus.