Bioactivity and chemical composition of the essential oil from the leaves of Guatteria australis A.St.-Hil

Essential oil from the leaves of Guatteria australis was obtained by hydrodistillation, analyzed by Gas Chromatography coupled to Mass Spectromery (GC–MS) and their antiproliferative, antileishmanial, antibacterial, antifungal and antioxidant activities were also evaluated. Twenty-three compounds were identified among which germacrene B (50.66%), germacrene D (22.22%) and (E)-caryophyllene (8.99%) were the main compounds. The highest antiproliferative activity was observed against NCI-ADR/RES (TGI = 31.08 μg/ml) and HT-29 (TGI = 32.81 μg/ml) cell lines. It also showed good antileishmanial activity against Leishmania infantum (IC₅₀ = 30.71 μg/ml). On the other hand, the oil exhibited a small effect against Staphylococcus aureus ATCC 6538, S. aureus ATCC 14458 and Escherichia coli ATCC 10799 (MIC = 250 μg/ml), as well as small antioxidant activity (457 μmol TE/g) assessed through ORAC_FL assay. These results represent the first report regarding chemical composition and bioactivity of G. australis essential oil.     

A new benzofuranolignan and a new flavonol derivative from the stem of Morus australis

A new benzofuranolignan austrafuran A （1） and a new flavonol derivative 5,7,2′,4′-tetrahydroxy-3-methoxyflavone （2） were isolated from the stem of Morus australis. Their structures were determined on the basis of spectroscopic evidences.     

Metabolites with Cytotoxic Activity from the Formosan Soft Coral Cladiella Australis

The metabolites, (24S)‐3β‐acetoxyergost‐5‐en‐21‐oic acid ( 2 ), 5′‐O‐acetylthymidine ( 3 ), 3′‐O‐acetylthymidine ( 4 ), and p‐vinylbenzyl alcohol ( 5 ), along with a known steroid ( 1 ) were isolated from the EtOAc extract of the Formosan soft coral Caldiella australis. The structures of new metabolites were determined on the basis of spectroscopic (including 1D and 2D NMR) analyses and by comparison of their NMR spectral data with those of related compounds. Except for 3 , all compounds exhibited cytotoxic activity of various degrees of potency against a limited panel of human liver and breast cancer cell lines.     

A novel bacteriohopanoid from Celtis australis L.bark

A novel bacteriohopanoid elucidated as 3β-hydroxy-35-(cyclohexyl-5’-propan-7’-one)-33-ethyl-34-methyl-bactereohopane(1) has been isolated from the bark of Celtis australis(Ulmaceae) together with three known compounds apigenin,quercetin and its glucoside.The structure of 1 was characterized by means of chemical and spectral methods including advanced 2D NMR studies.     

原子吸收光谱法测定芦苇中重金属(铜、锌、铅、镉)

采用密封高压消解样品,火焰原子吸收光谱法测定了芦苇中锌的含量,石墨炉原子吸收光谱法测定了芦苇中铜、铅、镉的含量.结果表明:铜、锌、铅和镉在芦苇不同部位的回收率分别为85.0%～120.4%,86.4%～106.5%,85.3%～86.2%和104.0%～114%;各元素分析结果精密度(RSD)分别为Zn0.72%～4.08%,Cu4.08%～6.27%,Pb4.12%～8.47%,Cd2.33%～5.59%,测定方法简便、准确,此方法的建立将为后继研究芦苇对重金属的吸收与积累,以及芦苇作为一种重金属污染指示性植物的利用提供技术支持.     

Antimalarials and Phytotoxins from Botryosphaeria dothidea Identified from a Seed of Diseased Torreya taxifolia

The metabolic pathways in the apicoplast organelle of Plasmodium parasites are similar to those in plastids in plant cells and are suitable targets for malaria drug discovery. Some phytotoxins released by plant pathogenic fungi have been known to target metabolic pathways of the plastid; thus, they may also serve as potential antimalarial drug leads. An EtOAc extract of the broth of the endophyte Botryosphaeria dothidea isolated from a seed collected from a Torreya taxifolia plant with disease symptoms, showed in vitro antimalarial and phytotoxic activities. Bioactivity-guided fractionation of the extract afforded a mixture of two known isomeric phytotoxins, FRT-A and flavipucine (or their enantiomers, sapinopyridione and (-)-flavipucine), and two new unstable γ-lactam alkaloids dothilactaenes A and B. The isomeric mixture of phytotoxins displayed strong phytotoxicity against both a dicot and a monocot and moderate cytotoxicity against a panel of cell lines. Dothilactaene A showed no activity. Dothilactaene B was isolated from the active fraction, which showed moderate in vitro antiplasmodial activity with high selectivity index. In spite of this activity, its instability and various other biological activities shown by related compounds would preclude it from being a viable antimalarial lead.     

Synchrotron X‐ray microfluorescence measurement of metal distributions in Phragmites australis root system in the Yangtze River intertidal zone

This study investigates the distributions of Br, Ca, Cl, Cr, Cu, K, Fe, Mn, Pb, Ti, V and Zn in Phragmites australis root system and the function of Fe nanoparticles in scavenging metals in the root epidermis using synchrotron X‐ray microfluorescence, synchrotron transmission X‐ray microscope measurement and synchrotron X‐ray absorption near‐edge structure techniques. The purpose of this study is to understand the mobility of metals in wetland plant root systems after their uptake from rhizosphere soils. Phragmites australis samples were collected in the Yangtze River intertidal zone in July 2013. The results indicate that Fe nanoparticles are present in the root epidermis and that other metals correlate significantly with Fe, suggesting that Fe nanoparticles play an important role in metal scavenging in the epidermis.     

Tracing antibacterial compounds from Acalypha australis Linn. by spectrum‐effect relationships and semi‐preparative HPLC

Several Acalypha australis Linn. species are used in traditional medicine in Southeast Asia. In this work, the ultra‐performance liquid chromatography/mass spectrometry fingerprints and the antibacterial activities of A. australis Linn. were investigated. An in‐depth discussion on the reliability of identifying and obtaining potentially active compounds by spectrum‐effect relationship and semi‐preparative high performance liquid chromatography was conducted. The result shows that gallic acid and a compound with molecular weight of 634.1 in the fingerprints were the main antibacterial compounds. Compared to the crude extract of A. australis Linn., both compounds increase the antibacterial efficacy 10 to 20 times. Compounds with molecular weights of 154.0, 292.0, and 485.1 in the fingerprints were the auxiliary antibacterial compounds. Through the entire isolation procedure, we obtained these antibacterial compounds with purities of 92.53, 87.98, 90.73, 89.36, and 88.14%, respectively. This work provides a general model of the combination of ultra‐performance liquid chromatography/mass spectrometry fingerprinting and antibacterial test to study the spectrum‐effect relationships of A. australis Linn. This model can be used to discover further the active compounds of this herb.     

Chemical Constituents from Fruits and Stem Bark of Celtis australis L.

Four triterpenoids named (9β,31R)‐9,25‐cyclo‐30‐propylhopan‐31‐ol ( 1 ), (3β)‐3‐hydroxy‐30‐propylhopan‐31‐one ( 2 ), (3β)‐oleanan‐3‐ol ( 3 ), and (3β,9β)‐9,25‐cycloolean‐12‐en‐3‐yl β‐D ‐glucofuranoside ( 4 ), a steroid named (3β,9β,14β)‐14‐hydroxy‐9,19‐cyclocholan‐3‐yl β‐D ‐glucopyranoside ( 5 ), and an anthraquinone named 6‐hydroxy‐5,7,8‐trimethoxy‐9,10‐dioxo‐9,10‐dihydroanthracen‐2‐yl acetate ( 6 ) have been isolated from the fruits and bark of Celtis australis (Ulmaceae), along with apigenin, quercetin, and its glucoside. Their structures were elucidated by means of chemical and spectral analysis including COSY, NOESY, and HMBC experiments.     

New phenyl derivatives from endophytic fungus Botryosphaeria sp. SCSIO KcF6 derived of mangrove plant Kandelia candel

Two new phenyl derivatives (1 and 3), along with two new natural products (4 and 5), and three known compounds (2, 6 and 7), were isolated from an endophytic fungus Botryosphaeria sp. SCSIO KcF6. The structures of these compounds 1–7 were elucidated by the extensive 1D and 2D-NMR and HRESIMS Data analysis, and compared with those of reported data. The absolute configuration of the compounds 1 and 3 were assigned by optical rotation and CD data. The isolated compounds were evaluated for their cytotoxic, anti-inflammatory (COX-2) and antimicrobial activities. Compound 3 exhibited a specific COX-2 inhibitory activity with the IC₅₀ value of 1.12 μM.