346

Mutagenicity testing of some mediciual herbs Riazuddin S; Malik MM; Nasim A ENVIRON. MOL. MUTAGEN.; lo/!2 (141- 1481/1987/

Extracts of four brands of a Pakastani local medicine called naswar and six indigenous herbs commonly used as medicine in children were tested for their ability to induce mutations to pro totrophy in Salmonella typhimurium tester strains TA98, TAlOO, TA1535, and TA1537. Petro leum ether extracts of one brand of naswar, namely green naswar of Peshawar, exhibited mutagenicity in all of the four tester strains. Organic extracts of three herbs, Saussurea lappa, Swertia chiraita, and Skimmia laureola, exhibited mutagenic activity in tester strain TA98. Green naswar of Bannu, grey naswar, red naswar, and the remaining three herbs, namely, Aco- rous calamus, Azadarachta indica, and Zanthozylum alatum, exhibited no mutagenic activity under the present experimental conditions. The abilities of green naswar of Peshawar and Saus- surea lappa to induce mutations was shown to be related to the presence of cyclic aromatic eom- pounds with molecular formulas C,H,O, and C,B,,O,, respectively. The experimental data are discussed as they relate to the potential hazards of such naturally occurring compounds and to synthetic compounds in excessive and uncontrolled use by the general public in villages in Paki- stan.

Flavonoids are scavengers of superoxide anions Robak J; Gryglewski RJ BIOCHEM. PHARMACOL.; 37/5 (837-8411/1988/

Seven flavonoids and three non-flavonoid antioxidants, i.e. butylated hydroxyanisole, chlorproma- zine and BW 755 C, were studied as potential scavengers of oxygen free radicals. Superoxide anions were generated enzymatically in a xanthine-xanthine oxidase system and non-enzymati- tally in a phenazine methosulphate-NADH system, and assayed by reduction of nitro blue tetra- zolium. The generation of malonaldehyde (MDA) by the ascorbate-stimulated air-oxidised boiled rat liver microsomes was considered as an index of the non-enzymatic formation of hydroxyl rad- icals. Flavonoids but not non-flavonoid antioxidants lowered the concentration of detectable superoxide anions in both enzymic and non-enzymie systems which generated these SOD-sensi- tive radicals. The most effective inhibitors of superoxide anions were quercetin, myricetin and rutin. Four out of seven investigated flavonoids seemed also to suppress the activity of xanthine oxidase as measured by a decrease in uric acid biosynthesis. AH ten investigated compounds inhibited the MDA formation by rat liver microsomes. Non-flavonoid antioxidants were more potent MDA inhibitors than flavonoids. It is concluded that antioxidant properties of flavonoids are affected mainly via scavenging of superoxide anions whereas non-flavonoid antioxidants act on further links of free radical chain reactions, most likely by scavenging of hydroxyl radicals.

Failure of diterpenes from Jatroplm curcas to induce mutation in Salmonella typbimdum

TA98 and TAlMl Rojanapo W; Pimbua J; Glinsukon T; et al RES. COMMUN. CHEM. PATHOL. PHARMACOL.; 5813 (397- 4001/1987/

No mutagenicity of five diterpenes isolated from the roots of Jatropha curcas was detected by Ames’s test using both TA98 and TAl99 tester strains with or without S-9 fraction from livers of rats treated with polychlorinated biphenyl.

Yellow oleander poisoning - A study of 170 cases Saravanapavananthan N; Ganeshamoorthy J FORENSIC SCI. INT.; 3613-4 (34t- 2501/1988/

Yellow oleander of Thevetia peruviana is a very common plant in the North of Sri Lanka. Ever since the fact that the fruits and kernel are poisonous was published in the Newspapers, many