Rhipicephalus (Boophilus) microplus is a tick that causes huge economic losses in cattle. The indiscriminate use of acaricides has generated resistance to most compounds present on the market. Carvacrol and salicylic acid have been widely studied for their biological activities and have been evaluated in different strains of Rhipicephalus. In this research the analogues carvacrol and salicylic acid were evaluated in larvae of R. (B.) microplus with data obtained in larval packet test (LPT) and larval immersion test (LIT). A lethal concentration 50 (LC50) was assessed. The most potent compounds were evaluated in the adult ticks since there are no reports of evaluation in the life state of the parasite. From all the tested compounds, the ethyl 2-methoxybenzoate (91.82 ± 1.66%, 0.91 μmol/mL) and ethyl 2,5-dihydroxybenzoate (89.14 ± 1.61%, 2.04 μmol/mL) showed the highest percentage of mortality and the lowest LC50. They were found to be the best candidates for a study in vivo.

A novel application of whole cells of Nocardia corallina B-276 for the deracemisation of ibuprofen is reported. This microorganism successfully hydrolysed ibuprofen nitrile to ibuprofen amide, and ibuprofen amide to ibuprofen, using a suspension of cells in a potassium phosphate buffer solution (0.1 M, pH = 7.0). These results can be explained by the presence of NHase and amidase enzymes, but the reactions are not enantioselective and low ee values were obtained. However, (R)-ibuprofen was isolated with >99% ee by a deracemisation process catalysed by N. corallina B-276. This is the first report of this kind of catalysis with this microorganism.

The aim of this research was to evaluate the redox system of Nocardia corallina B-276 in the biotransformation of 1-phenyl-1-propanone (1a), 2-hydroxy-1-phenylethanone (2a) and methyl (2-chlorophenyl)(oxo)acetate (3a) into 1-phenylpropan-1-ol (1b), 1-phenyl-1,2-ethanediol (2b) and methyl (2-chlorophenyl)(hydroxy)acetate (3b). The biomass of N. corallina was obtained in a liquid medium with an initial pH of 8.50, but the pH changed during the 96 h of the culture media, the final pH was between 4.74 and 7.62. The N. corallina biomass biocatalyzed the enantioselective reduction of 1a?3a to the corresponding alcohols. Whereas, during the process of oxidation of the rac-alcohols 1b?3b, 1b was oxidized in enantioselective way, the oxidation of 2b was not selective, but 3b was biotransformed mainly to (R)-3b. These results are indicative that N. corallina produced reductases and oxidases, whereby the biocatalytic activity was influenced by the final pH of the culture media, the reaction time and structure of the substrate.

The separation of the diastereoisomers of the nucleoside derivatives of uridine, inosine and adenosine was performed by HPLC using chiral and no chiral columns, it was observed with the no chiral columns the resolution was good enough to determine diastereoisomeric excess. These methods were compared with ¹H NMR, and no significant differences were observed between the three techniques. Diastereoisomeric uridine (3a), inosine (3b) and adenosine (4c) cyanohydrins were resolved by ¹H nuclear magnetic resonance (¹H NMR), chiral normal phase-high-performance liquid chromatography-diode array detector (NP-HPLC-DAD) and reversed phase (RP-HPLC-DAD); these methods allowed the assesment of the percent diastereoisomeric excess (% de) of the nucleosidic cyanohydrins of 3a (4, 6 and 4), 3b (10, 8 and 6) and 4c (4, 4 and 4). To the best of our knowledge, there are no reports using analytical techniques for the separation of the epimers of 3a, 3b and 4c.