The constituents of the root and stem of Aristolochia cucurbitifolia Hayata and their biological activity

Comparative Chemical Profiling and Antimicrobial/Anticancer Evaluation of Extracts from Farmed versus Wild Agelas oroides and Sarcotragus foetidus Sponges

Marine sponges are highly efficient in removing organic pollutants and their cultivation, adjacent to fish farms, is increasingly considered as a strategy for improving seawater quality. Moreover, these invertebrates produce a plethora of bioactive metabolites, which could translate into an extra profit for the aquaculture sector. Here, we investigated the chemical profile and bioactivity of two Mediterranean species (i.e., Agelas oroides and Sarcotragus foetidus) and we assessed whether cultivated sponges differed substantially from their wild counterparts. Metabolomic analysis of crude sponge extracts revealed species-specific chemical patterns, with A. oroides and S. foetidus dominated by alkaloids and lipids, respectively. More importantly, farmed and wild explants of each species demonstrated similar chemical fingerprints, with the majority of the metabolites showing modest differences on a sponge mass-normalized basis. Furthermore, farmed sponge extracts presented similar or slightly lower antibacterial activity against methicillin-resistant Staphylococcus aureus, compared to the extracts resulting from wild sponges. Anticancer assays against human colorectal carcinoma cells (HCT-116) revealed marginally active extracts from both wild and farmed S. foetidus populations. Our study highlights that, besides mitigating organic pollution in fish aquaculture, sponge farming can serve as a valuable resource of biomolecules, with promising potential in pharmaceutical and biomedical applications.

Alkaloids and styryllactones from Goniothalamus cheliensis

Eight previously undescribed compounds, including four alkaloids and five styryllactones together with 36 known compounds were isolated from the twig and leaf extracts of Goniothalamus cheliensis. Their structures were elucidated by extensive analysis of their spectroscopic data. The absolute configuration of (-)-(4S,5S,6R,7S,8S)-goniochelienlactone and (-)-(4S,5S,6R,7S,8S)-7-acetylgoniochelienlactone were established from single crystal X-ray analysis using Cu Kα radiation. The absolute configurations of the other related compounds were identified by comparisons of their ECD spectra with those of related known compounds. Most of the isolated compounds were evaluated for their cytotoxicities against human colorectal cancer cells (HCT-116). Griffithazanone A was the most potent with an IC₅₀ value of 2.39 μM.

Inhibition of Pro-Inflammatory Functions of Human Neutrophils by Constituents of Melodorum fruticosum Leaves

In an initial screening, the dichloromethane extract from the leaves of Melodorum fruticosum showed distinct inhibitory effects on the release of interleukin-8 (IL-8) in human neutrophils. Therefore, the aim of the present study was the phytochemical and pharmacological investigation of this extract, to better understand which compounds might be responsible for the anti-inflammatory effect. Phytochemical analysis led to the isolation of 12 known compounds and two new natural products, 5-hydroxy-6-(2-hydroxybenzyl)-4',7-dimethoxyflavanone (13) and 2',4'-dihydroxy-3'-(2-hydroxybenzyl)-4,6'-dimethoxychalcone (14). The influence of the isolated compounds on the production and release of the pro-inflammatory factors IL-8, tumor necrosis factor alpha (TNF-α), reactive oxygen species (ROS), and adhesion molecules (CD62L and CD11b) in human neutrophils was evaluated. Three constituents, melodamide A, 2',4'-dihydroxy-4,6'-dimethoxychalcone, and 2',6'-dihydroxy-4'-methoxychalcone, showed significant inhibition of IL-8 release (IC₅₀ =6.6, 8.6, and 11.6 μm, respectively) and TNF-α production (IC₅₀ =4.5, 13.3, and 6.2 μm, respectively).

Hinokinin, an emerging bioactive lignan

Hinokinin is a lignan isolated from several plant species that has been recently investigated in order to establish its biological activities. So far, its cytotoxicity, its anti-inflammatory and antimicrobial activities have been studied. Particularly interesting is its notable anti-trypanosomal activity.

Isolation, Characterization and Quantity Determination of Aristolochic Acids, Toxic Compounds in Aristolochia bracteolata L

BACKGROUND

Aristolochic Acids (AAs) are major components of plants in Aristolochia and have been found to be nephrotoxic, carcinogenic and mutagenic. Herein reported are the isolation, identification and quantity determination methods of Aristolochic Acid-I (AA-I) and Aristolochic Acid-II (AA-II) toxic compounds of Aristolochia bracteolata indigenous to Central Sudan and medicinally used in diverse biological functions including analgesic and diuretic effects, treatment of tumors, malaria and/or fevers.

METHODS AND RESULTS

AAs mixture was extracted with methanol from the defatted material of Aristolochia bracteolata whole plant at room temperature and was isolated from the aqueous methanol extract by chloroform. Moreover, Silica-gel column chromatography and Preparative Thin Layer Chromatography (PTLC) using chloroform/methanol gradient mixtures were used to isolate AAs mixtures as a yellow crystalline solid. A preliminary detection of AAs was made by Thin Layer Chromatography (silica-gel, chloroform: methanol (6:1)). The Rf value of the acids mixture was 0.43-0.46. The presence of AAs in plant sample was confirmed by High Performance Liquid Chromatography/Ultraviolet (HPLC/UV) analysis using 1% acetic acid and methanol (40:60) as mobile phase and maximum absorption wave length of 250 nm. Quantitative determination of AA-II (49.03 g/kg) and AA-I (12.98 g/kg) was also achieved by HPLC/UV.

RECOMMENDATION

It is recommended that the use of Aristolochia bracteolata as a medicinal plant should be extremely limited or strictly prohibited. The chromatograms obtained in this study can serve as fingerprints to identify AAs in plant samples.

Local uses of Aristolochia species and content of nephrotoxic aristolochic acid 1 and 2--a global assessment based on bibliographic sources

AIMS OF THE STUDY

More than 100 cases of nephropathy over the last 10 years caused by the systemic and longer term application of Chinese snakeroot (Aristolochia fangchi) highlighted the risk of using preparations which contain aristolochic acids. On the other hand anecdotal evidence highlights the widespread use of Aristolochia species (Aristolochiaceae) in many regions of the world. Therefore, it was our objective to systematically assess the scientific literature available on the local and traditional use of Aristolochia spp. on a worldwide scale. Our review identifies core species which need to be investigated and which may need monitoring (esp. in national and international trade).

METHODS

An extensive review of the literature available in libraries in London on the uses of species of Aristolochia was undertaken. Relevant information was extracted and entered into a database for analysis.

RESULTS

Based on the assessment of 566 reference sources 685 individual sets of data were recorded. Seven species--Aristolochia indica L. (Asia), Aristolochia serpentaria L. (North America), Aristolochia debilis Sieb & Zucch. (China), Aristolochia acuminata Lam (India), Aristolochia trilobata L. (Central/South America, Caribbean), Aristolochia clematitis L. (Europe) and Aristolochia bracteolata Lam. (Africa)--are reported widely as being used medicinally. The medical uses vary, but of particular interest are uses in case of gastrointestinal problems, which is likely to result in repeated exposure to the botanical drugs by an individual. About half of all records relate to uses of Aristolochia species in Asia, one-third to the Americas, a continent which has so far received practically no attention in terms of assessing the risk of using species of Aristolochia. Of the 99 species (plus several identified at genus level only) for which we were able to summarise ethnobotanical information, preliminary phytochemical information is only available for 24 species and some of the most common ones including Aristolochia acuminata have so far not been studied phytochemically.

CONCLUSIONS

Species of Aristolochia are used medicinally in many regions of the world and both from an ethnopharmacological and a public health perspective this poses a risk. A systematic assessment of the content of aristolochic acids in the most widely used species is needed to evaluate whether their uses pose a potential health risk. In China and Europe species of Aristolochia have been associated with nephropathy and it is important to evaluate whether nephropathy occurs in other parts of the world, especially India and Central America where the use of species of Aristolochia are reported to be commonly used in traditional medicine.

13C-NMR data of diterpenes isolated from Aristolochia Species

The genus Aristolochia, an important source of physiologically active compounds that belong to different chemical classes, is the subject of research in numerous pharmacological and chemical studies. This genus contains a large number of terpenoid compounds, particularly diterpenes. This work presents a compilation of the ¹³C-NMR data of 57 diterpenoids described between 1981 and 2007 which were isolated from Aristolochia species. The compounds are arranged skeletonwise in each section, according to their structures, i.e., clerodane, labdane, and kaurane derivatives. A brief discussion on the ¹³C chemical shifts of these diterpenes is also included.

The alkaloids and other constituents from the root and stem of Aristolochia elegans

Two new aristolactams, aristolactam E (1) and aristolactam-AIIIa-6-O-beta-D-glucoside (2), three novel benzoyl benzyltetrahydroisoquinoline ether N-oxide alkaloids, aristoquinoline A (3), aristoquinoline B (4), and aristoquinoline C (5), and a new biphenyl ether, aristogin F (6), together with 62 known compounds have been isolated from the root and stem of Aristolochia elegans Mast. The structures of the new natural products were established on the basis of spectral evidence. Some of the isolated compounds were examined for their antioxidative and antityrosinase activities. Occurrence of the isoquinolones, biphenyl ethers, and benzoyl benzyltetrahydroisoquinoline ether alkaloids in the same plant indicated the definite possibility of these metabolites as biotransformation intermediates of bisbenzyltetrahydroisoquinoline alkaloids. This can be useful to solve the catabolic process of bisbenzyltetrahydroisoquinoline alkaloids.

Molecular structures and antiviral activities of naturally occurring and modified cassane furanoditerpenoids and friedelane triterpenoids from Caesalpinia minax

Further investigation of the active components of the chloroform fraction of the seeds of Caesalpinia minax led to the isolation of a new cassane furanoditerpenoid, caesalmin H (1), together with two known furanoditerpenoid lactones, caesalmin B (2) and bonducellpin D (3). Reduction of the naturally abundant caesalmin D (9), E (10) and F (11) resulted in three new furanoditerpenoid derivatives 4-6. Phytochemical study of the stem of the same plant and subsequent reduction afforded two friedelane triterpenoids (7-8), which were identified by spectroscopic methods. Compounds 1-2 and 4-8 were corroborated by single crystal X-ray analysis. The factors governing the reduction of cassane furanoditerpenoids and friedelane triterpenoids were investigated by correlating the crystallographic results with density functional theory. The inhibitory activities of 2-8 on the Para3 virus were evaluated by cytopathogenic effects (CPE) reduction assay.