Chemical constituents of Aristolochia rigida and mutagenic activity of aristolochic acid IV

Asaroidoxazines from the Roots of Asarum asaroides Induce Apoptosis in Human Neuroblastoma Cells

Plants in the family Aristolochiaceae contain phenanthrene skeleton-containing chemical constituents that exhibit nephrotoxic, carcinogenic, mutagenic, anti-inflammatory, and cytotoxic effects. Two new phenanthrene-containing 1,2-oxazin-6-ones, designated as asaroidoxazine A (1) and asaroidoxazine B (2), and a known aristolactam, 5-methoxyaristololactam I (3), were isolated from the roots of Asarum asaroides. The structures of compounds 1 and 2 were determined using spectroscopic methods and X-ray crystallography. Treatment of SH-SY5Y human neuroblastoma cells with 1 μM of asaroidoxazine A (1) induced nuclear condensation as well as caspase-3/7 activation, indicating that this compound is a strong apoptosis inducer in neuronal cells. This is the first report of apoptosis induction by phenanthrene-containing oxazines.

LC-MS- and (1)H NMR-Based Metabolomic Analysis and in Vitro Toxicological Assessment of 43 Aristolochia Species

Species of Aristolochia are used as herbal medicines worldwide. They cause aristolochic acid nephropathy (AAN), a devastating disease associated with kidney failure and renal cancer. Aristolochic acids I and II (1 and 2) are considered to be responsible for these nephrotoxic and carcinogenic effects. A wide range of other aristolochic acid analogues (AAAs) exist, and their implication in AAN may have been overlooked. An LC-MS- and (1)H NMR-based metabolomic analysis was carried out on 43 medicinally used Aristolochia species. The cytotoxicity and genotoxicity of 28 Aristolochia extracts were measured in human kidney (HK-2) cells. Compounds 1 and 2 were found to be the most common AAAs. However, AA IV (3), aristolactam I (4), and aristolactam BI (5) were also widespread. No correlation was found between the amounts of 1 or 2 and extract cytotoxicity against HK-2 cells. The genotoxicity and cytotoxicity of the extracts could be linked to their contents of 5, AA D (8), and AA IIIa (10). These results undermine the assumption that 1 and 2 are exclusively responsible for the toxicity of Aristolochia species. Other analogues are likely to contribute to their toxicity and need to be considered as nephrotoxic agents. These findings facilitate understanding of the nephrotoxic mechanisms of Aristolochia and have significance for the regulation of herbal medicines.

Aza-polycyclic aromatic hydrocarbons from Saruma henryi

A new azafluoranthene alkaloid, named sarumine (1), along with six known N-containing derivatives of phenanthrenes, 2-7, were isolated from the whole herb of Saruma henryi. Their structures were elucidated on the basis of extensive spectroscopic analysis. Moreover, antimicrobial activities of all compounds were evaluated.

Screening of anti-bacterial activity of medicinal plants from Belize (Central America)

Twenty-one extracts from seven herbal drugs, Aristolochia trilobata (Aristolochiaceae) leaves and bark, Bursera simaruba (Burseraceae) bark, Guazuma ulmifolia (Sterculiaceae) bark, Hamelia patens (Rubiaceae) leaves and Syngonium podophyllum (Araceae) leaves and bark, used in traditional medicine of Belize (Central America) as deep and superficial wound healers, were evaluated for their anti-bacterial properties. Activity was tested against standard strains of Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Staphylococcus aureus ATCC 25923 and Enterococcus faecalis ATCC 29212. Almost all the extracts were able to inhibit the growth of one or more of the bacterial strains, except that of Enterococcus faecalis. For the first time an anti-microbial activity is reported for Aristolochia trilobata as well as for Syngonium podophyllum. The hexane extracts of Aristolochia trilobata leaves and bark were the most active extracts against Staphylococcus aureus (MIC=0.31 and 0.625mg/ml, respectively).

High-performance liquid chromatographic determination for aristolochic acid in medicinal plants and slimming products

A HPLC procedure with a silica gel RP-18 reversed-phase column for the determination of aristolochic acids I, II in medicinal plants and slimming products was developed. The mobile system 0.3% ammonium carbonate solution-acetonitrile (75:25, v/v) with pH 7.5 was the optimal buffer to clearly separate aristolochic acids I, II within 20 min. The recovery of aristolochic acids I, II in medicinal plants and slimming products was better than 90% by extracting with methanol and purifying through a PHP-LH-20 column. The major component was aristolochic acid I in Aristolochia fangchi and the level ranged from 437 to 668 ppm. Aristolochic acid II was the major component for Aristolochia contorta and its range was <1-115 ppm. Twelve out of 16 samples of slimming pills and powders contained aristolochic acids I and/or II. The major component in most slimming products was aristolochic acid II and the level ranged from <1 to 148 ppm. It may indicate that slimming products were not mainly made of A. fangchi.