Many essential oils (EOs) of different plant species possess interesting antimicrobial effects on buccal microorganisms and cytotoxic properties. EOs ofKielmeyera coriaceaMart. & Zucc. were analyzed by gas chromatography coupled to mass spectrometry (GC-MS). The EO from leaves is rich in sesquiterpenes hydrocarbons and oxygenated sesquiterpenes. The three major compounds identified were germacrene-D (24.2%), (E)-caryophyllene (15.5%), and bicyclogermacrene (11.6%). The inner bark EO is composed mainly of sesquiterpenes hydrocarbons and the major components are alpha-copaene (14.9%) and alpha-(E)-bergamotene (13.0%). The outer bark EO is composed mainly of oxygenated sesquiterpenes and long-chain alkanes, and the major components are alpha-eudesmol (4.2%) and nonacosane (5.8%). The wood EO is mainly composed of long-chain alkanes and fatty acids, and the major components are nonacosane (9.7%) and palmitic acid (16.2%). The inner bark EO showed the strongest antimicrobial activity against the anaerobic bacteriaPrevotella nigrescens(minimum inhibitory concentration-MIC of 50 µg mL−1). The outer bark and wood EOs showed MICs of 100 µg mL−1for all aerobic microorganisms tested. The EOs presented low toxicity to Vero cells. These results suggest thatK. coriacea, a Brazilian plant, provide initial evidence of a new and alternative source of substances with medicinal interest.
A diastereoselective three-component cascade reaction, catalyzed by p-sulfonic acid calix[4]arene, provides a unique method to access diverse julolidine derivatives in high yields. Additionally, the reaction was also monitored by mass spectrometry and the mechanistic pathway uncovered.
Maclura tinctoria(L.) D. Don ex Steud. has one of the highest qualities among the coefficients for Brazilian woods (up to 9.6) and resistance rates equivalent to Indian teak (Tectona grandis). In this study, the macromolecular constituents and total phenols compounds as well as the antioxidant and antibacterial activities of this wood were evaluated. Total phenols and proanthocyanidin levels were higher in wood when compared with bark levels. The antioxidant activity of wood extracts (IC50= 18.7 μg/mL) was more effective than that of bark extracts (IC50= 20.9 μg/mL). Wood and bark extracts revealed a high potential for inhibition of aerobic and anaerobic bacteria. The bark extracts were the most active (MIC from 20 to 60 μg/mL). Both antioxidant activity and high potential for bacteria inhibition turn these extracts promising for drug formulations, especially as antibacterial agent.