Studies on Hanguana (Commelinales, Hanguanaceae) for Sunda II: Five new forest species from Peninsular Malaysia and recircumscription of Hanguana malayana

Field work in Peninsular Malaysia as part of the first author's research into relationships and evolutionary polarity between Hanguana malayana, a widespread freshwater helophyte, and the numerous and mostly undescribed Sundaic forest species has to date resulted in the collection of five distinctive novel forest-dwelling Hanguana species. These are described here and figured in colour. Increased understanding of these and other forest species of Hanguana has enabled a concise delimitation of the taxonomically long-obfuscated colonial helophytic H. malayana, and this is here presented, and the species figured. The current taxonomy of Hanguana is summarised, and a key to the so-far described Peninsular Malaysian species is provided

Antioxidants in aqueous extract of Myristica fragrans (Houtt.) suppress mitosis and cyclophosphamide-induced chromosomal aberrations in Allium cepa L. cells

In this study, freeze-dried water extract from the leaves of Myristica fragrans (Houtt.) was tested for mutagenic and antimutagenic potentials using the Allium cepa assay. Freeze-dried water extract alone and its combination with cyclophosphamide (CP) (50 mg/kg) were separately dissolved in tap water at 500, 1000, 2000, and 4000 mg/kg. Onions (A. cepa) were suspended in the solutions and controls for 48 h in the dark. Root tips were prepared for microscopic evaluation. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) free radicals’ scavenging power of the extract was tested using butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) as standards. Water extract of Myristica fragrans scavenged free radicals better than BHA, but worse than BHT. The extract alone, as well as in combination with CP suppressed cell division, and induced chromosomal aberrations that were insignificantly different from the negative control (P≤0.05). However, cytotoxic and mutagenic actions of CP were considerably suppressed. The observed effects on cell division and chromosomes of A. cepa may be principally connected to the antioxidant properties of the extract. The obtained results suggest mitodepressive and antimutagenic potentials of water extract of the leaves of M. fragrans as desirable properties of a promising anticancer agent