Cytotoxic tirucallane C26 triterpenoids from the stem barks of Aphanamixis grandifolia

Five tirucallane type C₂₆ triterpenoids, accompanied by two known compounds, 3α-hydroxy-24,25,26,27-tetranortirucall-7-ene-23(21)-lactone and 3-oxo-24,25,26,27-tetranortirucall-7-ene-23(21)-lactone, were isolated from the stem barks of Aphanamixis grandifolia. Their structures were established mainly by means of a combination of 1D and 2D NMR spectroscopic and mass spectrometry techniques as 3α-hydroxyl-21α-methoxy-24,25,26,27-tetranortirucall-7-ene-23(21)-lactone, 3α-hydroxy-21β-methoxy-24,25,26,27-tetranortirucall-7-ene-23(21)-lactone, 3-oxo-21α-methoxy-24,25,26,27-tetranortirucall-7-ene-23(21)-lactone, 3-oxo-21β-methoxy-24,25,26,27-tetranortirucall-7-ene-23(21)-lactone, and 3-oxo-21α-ethoxy-24,25,26,27-tetranortirucall-7-ene-23(21)-lactone. All isolates were in vitro evaluated for their cytotoxic activities against five tumor cell lines (MCF-7, HeLa, HepG2, SGC-7901 and BGC-823).     

Isolation and characterization of ethanol-producing yeasts from fruits and tree barks

Aims:  Isolation and identification of yeasts converting xylose to ethanol.
Methods and Results:  A total of 374 yeasts were isolated from a variety of rotten fruits and barks of trees. Out of these, 27 yeast strains were able to assimilate xylose and produce 0·12–0·38 g of ethanol per gram of xylose. Based on phylogenetic analysis of D1/D2 domain sequence of LSU (Large Subunit) rRNA gene and phenotypic characteristics the ethanol-producing strains were identified as member(s) of the genera Pichia, Candida , Kluyveromyces, Issatchenkia, Zygosacchraomyces , Clavispora, Debaryomyces , Metschnikowia , Rhodotorula and Cryptococcus.
Conclusion:  Yeast strains producing ethanol from xylose have been isolated from a variety of rotten fruits and barks of trees and identified.
Significance and Impact of the Study:  Environmental isolates of yeasts which could convert xylose to ethanol could form the basis for bio-fuel production and proper utilization of xylan rich agricultural and forest wastes.     

Preliminary studies of micropropagation of Hopea odorata,a dipterocarp tree

Plantlet development from in vitro cultures of Hopea odorato Roxb. is described. Embryos excised from seeds and cultured on Gamborg's B5 or modified Murashige and Skoog (MS) medium with benzyladenine (BA, 2.2–22.2 M) produced axillary shoots at cotyledonary and/or stem nodes. Shoot production was greatest in germinated embryos on modified MS medium with 8.9 M BA. Excised axillary shoots formed few buds when cultured on medium with BA and limited root development occurred on Woody Plant Medium with naphthaleneacetic acid. Nodal explants from aseptically grown plantlets sprouted axillary shoots in modified MS medium with BA.Abbreviations BA 6-benzyladenine - 2,4-d 2,4-dichlorophenoxyacetic acid - GA₃ gibberellic acid - IBA indolebutyric acid - NAA naphthaleneacetic acid - PVPP polyvinylpolypyrrolidone     

A new chromanone acid from the bark of Calophyllum dryobalanoides

A new chromanone acid, calodryobalanoic acid, along with six known compounds, apetalic acid, isoblancoic acid, lupeol, 1-hydroxy-2-methoxyxanthone, 1,7-dihydroxy-3-methoxyxanthone, and 5,7,4′-trihydroxyflavanone, was isolated from the bark of Calophyllum dryobalanoides collected in Vietnam. The structure of the new compound was elucidated using mainly 1-D and 2-D NMR techniques (¹H and ¹³C NMR, HSQC, HMBC, COSY, and NOESY) and IR spectroscopy. The stereochemistry was determined on the basis of NMR results and DFT calculations.     

Cytotoxic chalcones and flavanones from the tree bark of Cryptocarya costata

A new flavanone, 7-hydroxy-5,6-dimethoxyflavanone (1), together with three other flavonoids, didymocarpin (2), 2',4'-dihydroxy-5',6'-dimethoxychalcone (3), and isodidymocarpin (4), had been isolated from the methanol extract of the tree bark of Cryptocarya costata. The structures of these compounds were determined based on spectral evidence, including UV, IR, 1-D and 2-D NMR, and mass spectra. Cytotoxic properties of compounds 1-4 were evaluated against murine leukemia P-388 cells. The chalcones 3 and 4 were found to have substantial cytotoxicity with IC50 of 5.7 and 11.1 microM, respectively.     

Chemotaxonomic significance of oligostilbenoids isolated from Dryobalanops in the taxonomic of Dipterocarpaceae

A phytochemical investigation of four species of Dryobalanops resulted in the isolation of 26 compounds. This study, reports the existence of several types of oligostilbenoids such as ampelopsin F (9), isoampelopsin F (10), stenophyllol A (15), upunaphenol D (17) and vaticanol C (20) that have not been reported from the tribe Shoreae. The data support previous studies using morphological characters that placed Dryobalanops in the tribe Dipterocarpeae. In addition, this is the first report of compounds with the skeletons of flexuosol A (16) and nepalensinol E (17) from Dipterocarpaceae.     

Using tree leaves and barks collected from contaminated and uncontaminated areas as indicators of air metallic pollution

Abstract

The aim of this study was to show the usefulness of woody species in assessing air pollution by cadmium, copper, lead, and zinc. For this, washed leaves, unwashed leaves, and barks of a coniferous species (Cupressus sempervirens var. fastigiata) and a broadleaved one (Eucalyptus cladocalyx F. Muell) were analyzed for cadmium, copper, lead and zinc contents. A transect sampling approach was carried out during spring 2016. Fifty stations were selected along an intensive traffic road, and three in a control area. The results showed that the highest concentrations were recorded in barks for copper (21.86?µg/g, 23.33?µg/g) and lead (14.53?µg/g, 63.33?µg/g), and in unwashed leaves for cadmium (0.57?µg/g, 1.19?µg/g) and zinc (48.94?µg/g, 47.6?µg/g) for E. cladocalyx F. Muell, and C. sempervirens var. fastigiata, respectively. Lead and zinc are the most accumulated metals compared to cadmium and copper in all samples. The studied metal contents in urban area were significantly higher than that of the control one. This represents that traffic road has influenced the metals contamination of the surrounding area. Results of the bioconcentration factor (BCF) for both species indicate that the studied species could be used as biomonitors to identify ecological problems and to predict effect on wildlife habitats. The highest values of metal accumulation index (MAI) indicate the effectiveness of these trees for controlling the air metals in the polluted areas. Result shows too that the studied species could be used for phytoextraction of heavy metals from the polluted soils and/or air.     

Flavan-3-ols from the barks of Barringtonia acutangula

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Atmospheric element deposit on tree barks: The opposite effects of rain and transpiration

The elemental composition of the deposit formed on the bark of ash-trees was studied over several months on stems ranging from 3 months to 10 years. For this purpose (1) the total elemental composition of the deposit, (2) the structure and composition of the solid particles and (3) the deposit dry weight per dm² were studied. Concurrently the part of this superficial deposit washed out by rain during 3.5 months was sampled at each rain event and its elemental composition analyzed. This study shows that the deposit was submitted to an intense turnover, with an average leaching-out flux reaching approximately 27 mg dm⁻² month⁻¹ and a very low increase of the deposit weight per dm² during the first five years and almost null afterwards. The origin of this superficial deposit was investigated. The main part (78 ± 10%) was organic matter originating from the atmospheric deposition or from the tree. The inorganic content originated partly from the atmosphere, with geogenic and anthropogenic particles, and also from the tree, in which it was demonstrated by scanning electron microscopy - energy dispersive X-ray that a non-negligible part was obtained from bark transpiration, inducing a superficial deposit, mainly of Ca or K in the area surrounding the lenticels. All those results demonstrate that this bark superficial deposit is a complex matrix which must not be considered as a simple cumulative archive but which seems to be the source of interesting information targeting mostly recent atmospheric pollution pressures, when compared to the bulk of suber integrated particles.     

Phytochemical and antinociceptive properties of Matayba elaeagnoides Radlk. barks

A mixture of triterpenes named lupeol (1), alpha-amyrin (2), beta-amyrin (3), and beta-sitosterol (4) has been isolated from the hexane fraction of Matayba elaeagnoides. In addition, scopoletin (5), umbelliferone (6), 3beta-O-D-glycopyranosyl-sitosterol (7) and betulin (8) were isolated from the chloroform fraction. All the structures were identified by spectroscopic techniques in accordance with literature data. The extracts (hydroalcoholic and methanolic) and some fractions (hexane, chloroform, ethyl acetate and butanol) exerted promising antinociceptive effects in mice. In addition, we have tested the pure compound betulin (8). When analyzed against induced pain using the writhing test (3-10 mg kg(-1), i.p.), betulin showed a dose-dependent effect with a calculated ID50 value of 7.74 (6.53-9.17) mg kg(-1) [17.5 (14.7-20.7) micromol kg(-1)] and a maximal inhibition (MI) of 58.3% in relation to the control group. When evaluated in the formalin test (3-10 mg kg(-1), i.p.), this compound inhibited both phases of pain (neurogenic and inflammatory pain), with calculated ID50 values of 18.3 (17.7-18.9) and 8.3 (7.7-8.9) mg kg(-1) [41.5 (38.4-42.7) and 18.8 (17.6-19.9) micromol kg(-1)] and maximal inhibition of 40.8 and 64.39% for the first and second phases, respectively. Using the same models, this compound was several times more active than two clinically used drugs, namely aspirin and paracetamol, suggesting that its main active principle is related to the antinociceptive effect found for the chloroform fraction of M. elaeagnoids barks.     

Antidiabetogenic oligostilbenoids and 3-ethyl-4-phenyl-3,4-dihydroisocoumarins from the bark of Shorea roxburghii

A methanol extract of the bark of Shorea roxburghii (Dipterocarpaceae) was found to inhibit plasma glucose elevation in sucrose-loaded mice. From the extract, three new 3-ethyl-4-phenyl-3,4-dihydroisocoumarins, 1'S-dihydrophayomphenol A(2) (1) and phayomphenols B(1) (2) and B(2) (3), were isolated together with 24 known compounds including 20 stilbenoids and oligostilbenoids. The structures of 1-3 were determined on the basis of their spectroscopic properties as well as of chemical evidences. Among the isolates, (-)-hopeaphenol (6), hemsleyanol D (8), (+)-α-viniferin (15), and (-)-balanocarpol (18) showed inhibitory activity against plasma glucose elevation in sucrose-loaded rats at doses of 100-200mg/kg, p.o. To clarify the mode of action of the antihyperglycemic property, effects of these oligostilbenoids on gastric emptying in mice, those on glucose uptake in isolated intestinal tissues as well as inhibitory activities against rat intestinal α-glucosidase and rat lens aldose reductase were examined.     

New vernocuminosides from the stem barks of Vernonia cumingiana Benth

Seven new stigmastane-type steroidal glycosides, vernocuminosides A-G (1-7), have been isolated from the stem barks of Vernonia cumingiana Benth. The structural elucidation and stereochemistry determination were achieved by spectroscopic and chemical methods including 1D and 2D NMR ((1)H-(1)H COSY, HSQC, HMBC, and NOE) experiments, especially the employment of Snatzke's method expressed by the induced circular dichroism spectra. Anti-inflammatory activities and cytotoxicities of compounds 1-7 were evaluated.     

New lignan glycosides from the root barks of Litsea glutinosa

An investigation on the chemical constituents in the root barks of Litsea glutinosa was performed for the first time. Three new lignan glycosides named Litseasins A–C (1–3), together with a known one (4), were obtained. The structures of the new compounds were established through extensive spectroscopic analyses including HR-ESI–MS, NMR, and circluar dichroism (CD). The new compounds were evaluated for their anti-inflammatory activities on lipopolysaccharide (LPS)-induce nitric oxide (NO) production in RAW264.7 murine macrophage cells. However, these compounds showed no inhibition on LPS-induced NO productions.     

Phytochemical constituents from the stem barks of Goniothalamus tapis Miq

Phytochemical investigation on the stem bark of Goniothalamus tapis Miq. led to the isolation of seven known styryl-lactones, 3-acetyl-isoaltholactone (1), goniothalamin (2), isoaltholactone (3), cheliensisin A (4), 7-epi-goniofufurone (5), goniopypyrone (6), garvensintriol (7), and two steroids, stigmasterol (8) and β-sitosterol (9). The structures of all the compounds were elucidated based on the analysis of spectroscopic data and comparison with reported literature. The chemotaxonomic significance of all these compounds were summarized. Among all the styryl-lactones, compound 1 was isolated naturally from plant for the first time while compounds 4, 5 and 7 have not been previously reported in Goniothalamus tapis Miq. Compound 2 was the first styryl-lactone isolated from many species of Goniothalamus including other families such as Cucurbitaceae, Lauraceae, Stemonaceae and Apocynaceae). Compounds 3 and 6 were found in ten species of Goniothalamus where the latter were also found in other genus (Polyalthia Blume).     

Stilbenoids in the stem bark of Hopea parviflora

From the bark of Hopea parviflora, two stilbenoids, named (+)-parviflorol and (-)-ampelopsin A, were isolated in addition to three known compounds: (+)-balanocarpol, (-)-epsilon-viniferin and (-)-hopeaphenol. Their structures were determined by analysis of spectral data, including 2D NMR and NOE experiments, respectively.     

Characterization of 15 polymorphic microsatellite loci in an endangered tropical tree Hopea bilitonensis (Dipterocarpaceae) in Peninsular Malaysia

This study reports the isolation and characterization of 15 polymorphic microsatellite loci in an endangered tropical tree Hopea bilitonensis (Dipterocarpaceae). The primers were designed from a genomic library enriched for dinucleotide (CT) repeats and screened on 24 adult trees from a natural population. The number of alleles ranged from two to eight, and the observed heterozygosity ranged from 0.042 to 1.000. These loci will allow mating system and population analyses to be carried out in this species.     

濒危植物狭叶坡垒的迁地保护

濒危植物狭叶坡垒 (H opea chinensis)是国家一级保护植物 ,原产我国广西十万大山、大青山。 1 990年 1 2月引入云南西双版纳热带植物园 (以下简称植物园 )栽培 ,9年来生长良好 ,树高年平均增加 0 .84m,地径年均加粗 1 .1 3 cm,比广西植物所种质园的植物生长快 ,树龄 3～ 5 a即开花结果 ,花期 5～ 7月 ,果熟期 9～ 1 0月 ,我园保存的 1 5 0株狭叶坡垒中有 1 0 0株已开花结果 ,种子发芽率极高 ,可达 94%± 6.0 % ;种子含水量与种子萌发的试验结果表明 :种子含水量与发芽率成显著的正相关关系 ,与播后首萌时间成显著的负相关关系。经多年观察 ,未见任何寒害和严重的病虫害 ,说明狭叶坡垒在西双版纳热带植物园迁地保护获得成功。