Evaluation of bio-agent formulations to control Fusarium wilt of tomato

The ED50 value of antagonistic substance from Chaetomium globosum N0802 extracted with hexane was 157 μg/ml. This gave the highest inhibition of conidial production of Fusarium oxysporum f. sp. lycopersici causing tomato wilt var Sida. Crude hexane from Chaetomium lucknowense CLT and crude methanol from Trichoderma harzianum PC01 gave ED50 values of 188 and 192 μg/ml. It clearly demonstrated that antagonistic substances from all tested fungi could be deformed and this could break the conidial cells. The bio-agent formulations namely N0802, CLT and PC01 gave significantly highest disease reduction of tomato wilt which were 44.68, 36.28 and 41.01%, respectively, followed by prochoraz (21.95%). All tested bio-agent formulations could significantly increase the yield of tomato when compared to prochoraz and inoculated control. It is concluded that C. globosum, C. lucknowense and T. harzianumKeywords: Fusarium oxysporum f. sp. lycopersici, Chaetomium globosum, Chaetomium lucknowense, Trichoderma harzianum, bio-agent formulationsAfrican Journal of Biotechnology Vol. 9(36), pp. 5836-5844, 6 September, 201

Analysis of additivity and synergism in the anti-plasmodial effect of purified compounds from plant extracts

In the search for antimalarials from ethnobotanical origin, plant extracts are chemically fractionated and biological tests guide the isolation of pure active compounds. To establish the responsibility of isolated active compound(s) to the whole antiplasmodial activity of a crude extract, the literature in this field was scanned and results were analysed quantitatively to find the contribution of the pure compound to the activity of the whole extract. It was found that, generally, the activity of isolated molecules could not account on their own for the activity of the crude extract. It is suggested that future research should take into account the “drugs beside the drug”, looking for those products (otherwise discarded along the fractionation process) able to boost the activity of isolated active compounds

Synthesis of alkaloid-like compounds via the bridging Ritter reaction

Alkaloid-like compounds containing a benzo[c]azepine core structure were successfully prepared in three steps from 5H-dibenzo[a,d]cyclohepten-5-ol via the bridging Ritter reaction. Biological studies of these compounds revealed that some of them are AChE inhibitors and antimalarial agents. © Springer-Verlag 2012