Novel Coumarin Glycosides from Daphne oleoides

`Dimeric' coumarin glycoside 1 and `trimeric' coumarin fucosides 2 and 3 were isolated from Daphne oleoides. Their structures were established by means of different spectroscopic techniques, including 2D‐NMR spectroscopy.     

Dapholidins A – C,New Isomeric Biisoflavonoids From Daphne oleoides

Three new isomeric biisoflavonoids, dapholidins A–C ( 1 – 3 , resp.), have been isolated from the AcOEt‐soluble fraction of the MeOH‐soluble extract of the roots of Daphne oleoides, along with the known compounds daphwazirin ( 4 ), daphnetin 8‐O‐β‐D ‐glucopyranoside ( 5 ), daphnin ( 6 ), daphneticin 4″‐O‐β‐D ‐glucopyranoside ( 7 ), and 6,7‐dihydroxy‐3‐methoxy‐8‐[2‐oxo‐2H‐1‐benzopyran‐7‐(O‐β‐D ‐glucopyranosyl)‐8‐yl]‐2H‐1‐benzopyran‐2‐one ( 8 ). The structures of the new compounds were determined by spectroscopic analyses, including 1D‐ and 2D‐NMR.     

Ligustri Lucidi Fructus as a traditional Chinese medicine: a review of its phytochemistry and pharmacology

Ligustri Lucidi Fructus (LLF) is the fruits of Ligustrum lucidum Ait. (Oleaceae). This review based on nearly 80 literary sources discusses the knowledge of chemistry and biological effects of this species. Several types of chemical constituents considered as the characteristic and active constituents from LLF were isolated including 40 triterpenoids, 48 iridoids, 10 flavones, 10 phenylethanoid glycosides and others. Various extracts and individual compounds derived from this species have been found to possess a variety of pharmacological effects, e.g. anti-tumour, hepatoprotective, immune regulating, antioxidative and anti-ageing effects, anti-inflammation and reducing hypercholesterolaemia effects and so on. The results of data analysis on the chemical, pharmacological characteristics of LLF support the view that this species has many therapeutic properties and indicate its potential as an effective herbal remedy. Finally, some suggestions for further research on chemical and pharmacological properties are given in this review. Theoretical basis was given for further exploiting and utilising LLF.     

A Lignoid Glycoside and Dimeric Phenylpropanoids from Daphne oleoides

Three new natural products, a lignoid glycoside 1 and two dimeric phenylpropanoids 2 and 3 , along with two known lignans 4 and 5 , were isolated from the BuOH‐ and CHCl₃‐soluble fractions of the whole plant of Daphne oleoides (Thymelaeaceae). The structures of the new compounds were established by spectroscopic techniques, including 2D NMR, as 4‐(β‐D ‐glucopyranosyloxy)‐9′‐hydroxy‐3,3′,4′‐trimethoxy‐7′,9‐epoxylignan ( 1 ), (1R,2S,5R,6R)‐6‐(3‐ethyl‐4‐hydroxy‐5‐methoxyphenyl)‐2‐(4‐hydroxy‐3,5‐dimethoxyphenyl)‐3,7‐dioxabicyclo[3.3.0]octane ( 2 ) and (1R,2S,5R,6S)‐2,6‐bis(3‐ethyl‐4‐hydroxy‐5‐methoxyphenyl)‐3,7‐dioxabicyclo[3.3.0]octane ( 3 ). The other lignans were identified as (+)‐pinoresinol O‐(β‐D ‐glucopyranoside) ( 4 ) and (+)‐medioresinol ( 5 ).     

Phytochemical investigation of Euphorbia trigona

Euphorbia species (Family: Euphorbeaceae) have wide applicability in traditional medicines and biofuel sector, and are also rich sources of secondary metabolites, especially terpenoids, attributed with various pharmacological properties. Though 82 Euphorbia species are reported in India, most of the species are uninvestigated for their constituents or potential utilities. Present study reports the isolation and characterization of chemical constituents, estimation of major triterpenoids using a validated HPTLC method and cytotoxicity of plant and latex extracts of Euphorbia trigona. As the secondary metabolites epi-friedelinyl acetate, 3β-friedelinol, taraxerol, rhoiptlenone, stigmasterol and stearic acid were isolated and characterized from E. trigona. HPTLC estimation showed 3β-friedelinol at 0.91 ?± ?0.11% and taraxerol at 1.45 ?± ?0.12% was present in E. trigona plant powder (dry weight). Plant and latex extracts were found non toxic towards normal cell line H9C2 (cardiac myoblasts) and showed insignificant cytotoxic effects towards HeLa (cervical cancer cell line) upto 100 ?μg/ml concentration.     

Chemistry and Pharmacological Activity of Sesquiterpenoids from the Chrysanthemum Genus

Plants from the Chrysanthemum genus are rich sources of chemical diversity and, in recent years, have been the focus of research on natural products chemistry. Sesquiterpenoids are one of the major classes of chemical constituents reported from this genus. To date, more than 135 sesquiterpenoids have been isolated and identified from the whole genus. These include 26 germacrane-type, 26 eudesmane-type, 64 guaianolide-type, 4 bisabolane-type, and 15 other-type sesquiterpenoids. Pharmacological studies have proven the biological potential of sesquiterpenoids isolated from Chrysanthemum species, reporting anti-inflammatory, antibacterial, antitumor, insecticidal, and antiviral activities for these interesting molecules. In this paper, we provide information on the chemistry and bioactivity of sesquiterpenoids obtained from the Chrysanthemum genus which could be used as the scientific basis for their future development and utilization.     

Phytoconstituents and pharmacological activities of cyanobacterium Fischerella ambigua

Cyanobacteria, also known as blue-green algae, are known to be a rich source of secondary metabolites with diverse chemical structures and biological activities. Over 1100 natural constituents of cyanobacterial origin have been reported in the literature. These include various natural biologically active constituents with antimicrobial, antiviral, immunosuppressive, and anticancer activities. Terrestrial cyanobacteria of genus Fischerella (Family Fischerellaceae), belonging to order Stigonematales have recently received enormous attention from the researchers due to the presence of vast array bioactive compounds. Fischerella species are filamentous cyanobacteria with creeping thallus and sheath in filaments. Several species within the genus are known to produce interesting bioactive constituents. Perhaps the best characterized are F. ambigua and F. muscicola, which have been reported to produce antibacterial, antifungal and antialgal isonitrile containing indole alkaloids, such as hapalindoles, ambiguine isonitriles, fischerindoles, and wetwitindolinones. Keeping in mind these resources, a detailed literature survey on a cultured, fresh water and terrestrial cyanobacterium Fischerella ambigua (N?g.) Gom. has been carried out. The current review describes the chemical constituents isolated from different extracts of Fischerella ambigua, as well as their biological activities.     

From Adlayer Islands to Surface Alloy: Structural and Chemical Changes on Bimetallic PtRu/Ru(0001) Surfaces

The correlation between structural and chemical properties of bimetallic PtRu/Ru(0001) model catalysts and their modification upon stepwise annealing of a submonolayer Pt‐covered Ru(0001) surface up to the formation of an equilibrated Pt_xRu_1?x/Ru(0001) monolayer surface alloy was investigated by scanning tunneling microscopy and by the adsorption of CO and D₂ probe molecules. Both temperature‐programmed desorption and IR measurements demonstrate the influence of the surface structure on the adsorption properties of the bimetallic surface, which can be explained by changes of the composition of the adsorption ensembles (ensemble effects) for D adsorption and by changes in the electronic interaction (ligand effects, strain effects) of the metallic constituents for CO and D adsorption upon alloy formation.     

Phytochemical profiles,antioxidant and anti-acetylcholinesterasic activities of the leaf extracts of Rhamnus lycioides subsp. oleoides (L.) Jahand. & Maire in different solvents

In this work, the extracts obtained with different solvents from the leaves of Rhamnus lycioides subsp. oleoides (L.) Jahand. & Maire were studied for their phytochemical profile and then for their antioxidant and acetylcholinesterase inhibitory activities. The phytochemical profiles of the extracts in n-hexane, dichloromethane, ethyl acetate, methanol, anthraquinone rich and water, showed the presence of different compounds belonging to several classes of natural products such as flavonoids, anthraquinones, saccharides and fatty acids. For what concerns the biological tests, the ethyl acetate, methanol and anthraquinone rich extracts showed the highest activities in both assays due to the high amount of compounds possessing those properties such as flavonoids and anthraquinones. By consequence, these specific extracts of the species may be considered to be potential sources of natural antioxidant and anti-acetylcholinesterasic compounds.     

Phytochemistry and Pharmacological Activities of the Diterpenoids from the Genus Daphne

There are abundant natural diterpenoids in the plants of the genus Daphne from the Thymelaeaceae family, featuring a 5/7/6-tricyclic ring system and usually with an orthoester group. So far, a total of 135 diterpenoids has been isolated from the species of the genus Daphne, which could be further classified into three main types according to the substitution pattern of ring A and oxygen-containing functions at ring B. A variety of studies have demonstrated that these compounds exert a wide range of bioactivities both in vitro and in vivo including anticancer, anti-inflammatory, anti-HIV, antifertility, neurotrophic, and cholesterol-lowering effects, which is reviewed herein. Meanwhile, the fascinating structure–activity relationship is also concluded in this review in the hope of providing an easy access to available information for the synthesis and optimization of efficient drugs.     

Phytochemical studies on the Australian native plant species Acacia pycnantha and Jacaranda mimosifolia D.Don*

In ongoing investigations into colours in Nature, the chemical constituents from the flowers of Acacia pycnantha and Jacaranda mimosifolia D.Don grown in Australia are reported. Eight known secondary metabolites were isolated from the A. pycnantha flower including isosalipurposide (7) which may be responsible for their distinctive colouration. Nine secondary metabolites were isolated from the J. mimosifolia D.Don flower including the new phenylethanoid β-D-glucopyranose (10). All isolated compounds were inactive against bacteria tested at concentration of 32 μg/mL.     

Structures and Bioactivities of Steroidal Saponins Isolated from the Genera Dracaena and Sansevieria

The species Dracaena and Sansevieria, that are well-known for different uses in traditional medicines and as indoor ornamental plants with air purifying property, are rich sources of bioactive secondary metabolites. In fact, a wide variety of phytochemical constituents have been isolated so far from about seventeen species. This paper has reviewed the literature of about 180 steroidal saponins, isolated from Dracaena and Sansevieria species, as a basis for further studies. Saponins are among the most characteristic metabolites isolated from the two genera. They show a great variety in structural motifs and a wide range of biological activities, including anti-inflammatory, anti-microbial, anti-proliferative effects and, in most case, remarkable cytotoxic properties.     

A novel daphnane-type diterpene from the flower bud of <Emphasis Type="Italic">Daphne genkwa</Emphasis>

A novel daphnane-type diterpene, genkwanin I (1), and a novel natural product, orthobenzoate 2 (2), were isolated from the flower bud of Daphne genkwa. The structures of the two compounds were elucidated by spectral techniques, viz.1D, 2D NMR spectra and HR-ESI-MS. Genkwanin I showed inhibitory activity against human promyelocytic HL-60 cells at an IC₅₀ level of 11.74 μM.     

A simple and efficient protocol for large‐scale preparation of three flavonoids from the flower of Daphne genkwa by combination of macroporous resin and counter‐current chromatography

In this paper, macroporous resin column chromatography and counter‐current chromatography (CCC) were applied for large‐scale preparative separation of three flavonoids from the flower of Daphne genkwa, a famous Chinese medicinal herb. Nine kinds of resins were investigated by adsorption and desorption tests and D101 macroporous resin was selected for the first cleaning‐up, in which 40% aqueous ethanol was used to remove the undesired constituents and 90% aqueous ethanol was used to elute the targets. The crude extract after the first step was directly subjected to the preparative CCC purification using the solvent system composed of n‐hexane–ethyl acetate–methanol–water (4:5:4:5, v/v). The compounds apigemin (823 mg), 3‐hydroxyl‐genkwanin (842 mg) and genkwanin (998 mg) with the purities of 98.79, 97.71 and 93.53%, respectively, determined by HPLC were produced from 3‐g crude extract only in one CCC run. Their chemical structures were identified by MS, UV and the standards.     

Daphne striata Tratt. and D. mezereum L.: a study of anti-proliferative activity towards human cancer cells and antioxidant properties

In this study, we investigated for the first time the anti-proliferative and antioxidant properties of D. mezereum and D. striata. The aerial parts were extracted by maceration with n-hexane, dichloromethane, and methanol. MPLC, GC, and GC-MS were used for the phytochemical study. The anti-proliferative activity was tested against MCF-7, A549, LNCaP, ACHN, and C32 cancer human cells. The antioxidant activity was measured by employing β-carotene bleaching, ABTS, DPPH, and FRAP tests. The Relative Antioxidant Capacity Index (RACI) was applied from the perspective of statistics. D. mezereum dichloromethane extract showed a remarkable anti-proliferative with an IC₅₀ of 6.08 μg/mL against LNCaP cells. Experimental data indicate that Daphne species have interesting anti-proliferative and antioxidant properties that deserve more investigations to develop novel antineoplastic drugs.     

Tanacetamide D: A New Ceramide from Tanacetum artemisioides

One new ceramide (=long‐chain base linked to a fatty acid via an amide bond), tanacetamide D ( 1 ), was isolated from Tanacetum artemisioides. Besides this, the two known constituents 5‐demethylnobiletin ( 2 ) and 5‐hydroxy‐3,6,7,8,3′,4′‐hexamethoxyflavone ( 3 ) were isolated for the first time from this species. The structure elucidation of the isolated compounds were based primarily on 2D‐NMR techniques including correlation spectroscopy (COSY), heteronuclear multiple‐quantum coherence (HMQC), heteronuclear multiple‐bond correlation (HMBC), and nuclear Overhauser effect spectroscopy (NOESY) experiments.     

Two new aromadendrane sesquiterpenes from Verticillium psalliotae

The chemical constituents of the fungus Verticillium psalliotae were studied. Two new aromadendrane sesquiterpenes inonotin M (1) and inonotin N (2) were isolated from the EtOAc extract of the fungal culture broth. The structures of compounds were elucidated mainly by HRESIMS experiments, and 1D, 2D-NMR spectroscopy analysis.     

Daphnane‐Type Diterpenoids from the Flower Buds of Daphne genkwa

Three new daphnane‐type diterpenoids, genkwanines M–O ( 1 – 3 , resp.), together with seven known daphnane‐type diterpenoids, genkwanines D and H, genkwaine F, genkwadaphnine, yuanhuatine, yuanhuafine, and yuanhuapine ( 4 – 10 , resp.), were isolated from the flower buds of Daphne genkwa during a phytochemical investigation. The structures of the new compounds were elucidated on the basis of spectroscopic analyses, especially 2D‐NMR spectra (HSQC, HMBC, and NOESY).     

Chemical fingerprint analysis and metabolic profiling of 50% ethanol fraction of Lomatogonium rotatum by ultra‐performance liquid chromatography/quadrupole–time of flight mass spectrometry

Lomatogonium rotatum (L.) Fries ex Nym (L. rotatum), a member of Gentianaceae, is an important mongolian medicine in China used to treat febrile diseases in liver and gallbladder. The aim of present study was to investigate the chemical constituents and metabolites of the 50% ethanol fraction of L. rotatum (50EtLR). Firstly, the extract of L. rotatum was partitioned by macroporous resin to obtain the target fraction (50EtLR), then several compounds were isolated from 50EtLR to obtained the standards for further analysis of chemical constituents of 50EtLR. Secondly, the chemical constituents of 50EtLR were characterized using the ultra‐high performance liquid chromatography coupled with quadrupole–time‐of‐flight mass spectrometry (UHPLC–Q‐TOF–MS/MS). Finally, prototype constituents and related metabolites were analyzed after orally administerng 50EtLR to rats. As a result, a new compound, 6‐O‐[β‐d ‐xylopyranosyl‐(1 → 6)‐O‐β‐d ‐glucopyranosyl]‐1,4,8‐trimethoxyxanthone ( 6 ) along with seven known compounds ( 1–5 , 7 and 8 ) were isolated from the 50EtLR, 92 components were either unambiguously or tentatively identified. Additionally, 34 prototype constituents and 112 metabolites in rat plasma along with 32 prototype constituents and 53 metabolites in rat liver were tentatively identified. Therefore, xanthones and flavonoids were the main chemical constituents of 50EtLR and sulfation and glucuronidation are the main enzyme‐induced metabolic pathways involved post‐administration.     

Chinese Oak Tasar Silkworm Antheraea pernyi Silk Proteins: Current Strategies and Future Perspectives for Biomedical Applications

Chinese nonmulberry temperate oak tasar/tussah, Antheraea pernyi (Ap) silk is a natural biopolymer that has attracted considerable attention as a biomaterial. The proteinaceous components of Ap silk proteins, namely fibroin and sericin may represent an alternative over mulberry Bombyx mori silk proteins. In fact, the silk fibroin (SF) of Ap is rich in Arginyl‐Glycyl‐Aspartic acid (RGD) peptides, which facilitate the adhesion and proliferation of various cell types. The possibility of processing Ap silk proteins into different distinct 2D‐ and 3D‐based matrices is described in earlier studies, such as membranes, nanofibers, scaffolds, and micro/nanoparticles, contributing to a different rate of degradation, mechanical properties, and biological performance useful for various biomedical applications. This review summarizes the current advances and developments on nonmulberry Chinese oak tasar silk protein (fibroin and sericin)‐based biomaterials and their potential uses in tissue engineering, regenerative medicine, and therapeutic delivery strategies.