Safety evaluation of Agaricus subrufescens varieties and their products of therarpeutic interest or for disease prevention

National audienceMushrooms are food traditionally consumed in Europe, Asia and America. They are being studied for medicinal benefits. Extensive studies have shown that Agaricus subrufescens ( A. blazei Murrill or A. brasiliensis) has anticancer properties. A comparative study of Agaricus subrufescens strains (from Brazil and France) is presented herein using Agaricus bisporus (champignon de Paris) as control. In vivo OCDE test were performed to evaluate either tolerance and/or acute and sub chronic toxicity in rats and mice. Our data reveal that all A. subrufescens strains are not toxic, either in vivo or in vitro, except some locomotor hypoactivity. All show a preventing effect against carcinogenesis, including A. bisporus. This is the first time that this mushroom is shown to be effective, even thought it is clearly less effective than A. subrufescens. However no anti tumour effect is found using Balb-c mice implanted with leukaemia cells. Furthermore they elicit slight cell growth stimulation at the concentrations tested in vitro, in Hep G2 (human hepatoma cells) and Neuro 2a (mouse neuroblastoma cells). The most active is A. subrufescens from Brazil. These mushrooms do have many bioactive compounds, different from the polysaccharides that need to be isolated and characterised for their curative properties following accurate evaluation of toxicological effects. Indeed there is clearly a lake of information on toxicological assessment (acute and chronic toxicity) of compound such as agaritine, blazein among others and of the whole mushroom A. subrufescens itself, and overall on epidemiological data linking the consumption of Agaricus sp and eventual prevention and/or pathologies

Acute and Sub-chronic (28-day) Oral Toxicity Studies of Hydroalcohol Leaf Extract of Ageratum conyzoides L (Asteraceae)

Purpose: Ageratum conyzoides is an annual herbaceous plant commonly used in African traditional medicine as a purgative, antipyretic, anti-ulcer and wound dressing agent. The objective of this study was to investigate the acute and sub-chronic toxicity of A. conyzoides leaves in Wistar rats. Methods: In the acute test, the limit test dose of 5000 mg/kg was administered to Wistar rats and then observed individually 1 h post-dosing, and at least once daily for 14 days. Sub-chronic toxicity was evaluated after administering daily oral doses of 500 and 1000 mg/kg body wt., for 28 days to the rats, Biochemical and haematological assessments as well as body and relative organ weights of the rats were carried out Results: The limit dose of 5000 mg/kg did not cause any mortality or signs of acute toxicity in the rats tested during the observation period. In the sub-chronic tests, the results did not show any treatment– related abnormalities in terms of haematological and biochemical parameters. However, urea was significantly (p < 0.05) lower in the group treated with 500 mg/kg of A. conyzoides extract. The weekly body and organ weight of the rats showed no significant differences between the control and the rats treated with the extract except for liver where there was a significant increase (p < 0.05) in rats that received 1000 mg/kg, i.e., 3 ± 0.2 g as against 2.5 ± 0.1 g for the control. Conclusion: Our results suggest that the hydroalcohol extract of A. conyzoides is relatively safe when administered orally in rats

CO-OCCURRENCE OF AFLATOXIN B1, FUMONISIN B1, OCHRATOXIN A AND ZEARALENONE IN CEREALS AND PEANUTS IN COTE D'IVOIRE

International audienceThe present survey examined 30 samples of rice (n=10), maize (n=10) and peanuts (n=10) from Côte d'Ivoire for aflatoxin B1, fumonisin B1 and zearalenone using immuno-assays, and ochratoxinA using a validated HPLC-florimetric method. Similarly to some other countries it appeared that in Côte d'Ivoire several mycotoxins are present in the same commodities. These mycotoxins are from different structural families: aflatoxin B1, fumonisin B1, zearalenone, and ochratoxin A. There are normally produced by fungal species from Aspergillus, Penicilium and Fusarium genera. Some samples contain four mycotoxins (86%). Four peanuts samples do not show ochratoxin A (14%) whereas they contain threatening aflatoxin B1 concentrations, above the EU regulatory limits and exceeding tolerable daily intake. The concentrations of ochratoxin A, zearalenone and fumonisin B1 are low and may not cause problem per se however fears remain for possible excess of tolerable daily intake due to eating habits and synergism with the combination of several mycotoxins. Investigations in this direction are underway together with isolation and characterization of fungal species involved

Assessment of pesticides residues contents in the vegetables cultivated in urban area of Lome (southern Togo) and their risks on public health and the environment, Togo

International audienc