Tian Nan Xing

A 60-year-old man ingested a raw Arisaema amurense rhizome as a medicinal herb and developed oral pain and swelling that progressed to aphonia and hypersalivation; he required endotracheal intubation for airway protection and was managed with antihistamines and corticosteroids. The authors attribute the injury to calcium oxalate content and note that reported effects range from oral oedema through oesophageal erosion to hypocalcaemia. Human evidence, on one of the three species that supply this drug, that the unprocessed rhizome is dangerous by mouth.

A 4-year-old presented two hours after chewing the root of an unidentified garden plant, later identified as Arisaema triphyllum, with excessive salivation, inability to speak, posterior pharyngeal congestion and uvular swelling. The authors attribute the picture to calcium oxalate crystals and note the range from minor oral oedema to lethal airway obstruction. A congener rather than a pharmacopoeial source species, included because it independently documents the raphide syndrome in a human.

Rat study comparing crude Arisaema erubescens with the two traditional processed products, Arisaematis Rhizoma Praeparatum (ginger juice and alum) and Arisaema cum Bile (bovine bile). Crude drug produced renal tubular vacuolar degeneration with raised IL-1 beta, TNF-alpha and malondialdehyde and reduced antioxidant enzymes; untargeted metabolomics identified 35 candidate biomarkers in amino acid, glycerophospholipid and fatty acid metabolism, and both processing methods attenuated the perturbation. This is the closest thing to experimental validation that processing detoxifies the drug, and it is animal-level.

Concerns the bile-processed drug rather than this record's rhizome, and is cited to define the boundary between them. Gas chromatography ion-mobility spectrometry identified 17 volatile organic compounds separating fermentation stages, with three months proposed as the optimal time and Enterococcus and Staphylococcus as the likely producing organisms. Arisaema cum bile at 2.8 g/kg orally increased seizure latency and shortened seizure duration in hot-water-bath-induced febrile seizures in rats, preserved hippocampal neurons, raised GABA-A receptor and lowered GRIA1 expression, and shifted gut microbiota. No equivalent anticonvulsant evidence exists for the ginger-and-alum processed rhizome.

Isolation and characterisation of a lectin from A. erubescens tubers, with demonstration of pro-inflammatory activity. Establishes that the acrid toxicity of the raw drug is not attributable to calcium oxalate crystals alone but also to protein packaged with them, which is why processing steps that denature protein reduce irritancy.

Raphides purified from A. erubescens tubers were 89.46 percent calcium oxalate, 7.4 percent protein and 0.48 percent polysaccharide, and were strongly molluscicidal against the schistosomiasis snail Oncomelania hupensis (48-hour LC50 70.95 mg/L, 72-hour LC50 44.25 mg/L). Potency ranked intact raphides above isolated calcium oxalate crystals above isolated lectin. Electron micrographs showed needles sharp at both ends, grooved on both sides and partly barbed. A molluscicide study, not a therapeutic one, but the best quantitative anatomy of the toxic principle.

Bioassay-guided fractionation of an ethanol extract of A. erubescens tubers yielded schaftoside and isoschaftoside, with nematocidal LC50 values of 114.66 and 323.09 micrograms per millilitre against Meloidogyne incognita. Source of the identity and relative abundance of the tuber's flavone C-glycosides; no relevance to human dosing.