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The aim of this work was to evaluate the antibacterial activity of Brazilian plants extracts against fish pathogenic bacteria. Forty six methanolic extracts were screened to identify their antibacterial properties against Streptococcus agalactiae, Flavobacterium columnare and Aeromonas hydrophila. Thirty one extracts showed antibacterial activity.

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A mild, practical, and straightforward protocol for the construction of endocyclic enecarbamates starting from N-acyl lactams and N-acyl pyrrolidines is presented. Lactams were reduced to the corresponding alpha-hydroxycarbamates in good to excellent yields using DIBAL-H, SuperHydride, or NaBH(4) followed by beta-elimination (dehydration) promoted by trifluoroacetic anhydride in the presence of hindered nitrogenated bases such as 2,6-lutidine, diisopropylethylamine, or triethylamine. Small variations of this protocol permitted the preparation of several endocyclic enecarbamates (12 examples) in good to excellent overall yields (56-96%). The protocol was demonstrated to be applicable to several ring sizes, compatible with different protecting groups, and to be mild enough to prevent racemization of racemization-prone stereocenters. The efficacy of the procedure in the preparation of enantiomerically pure endocyclic enecarbamates was also demonstrated and compared to the commonly used Shono's protocol, which in our hands led to partial racemization of the endocyclic enecarbamate 18c.

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This work aimed to select potentially useful rhizobacteria for the control of Meloidogyne exigua, a widely disseminated root-knot nematode found in Brazilian coffee fields. Initially, crude metabolites produced in liquid medium by 69 isolated rhizobacteria strains (previously obtained from several plants collected in the south of Minas Gerais State, Brazil) were tested in vitro for lethality towards M. exigua second stage juveniles (J 2 ). Substances produced by strains of Bacillus cereus, B. megaterium, B. pumilus, B. thuringiensis, Enterobacter asburiae, E. cloacae and Paenibacillus macerans caused high mortality in J 2 . Subsequently, the ten most active crude metabolites were selected and assessed for nematicidal activity in a biotest with M. exiguainoculated coffee plants. Although strains of B. cereus, B. pumilus and P. macerans caused a significant reduction in the number of root galls and/ or nematode eggs per plant 90 days after treatment, the best results were obtained with the application of B. megaterium strain 54-06.

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