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This work aimed to obtain and investigate the properties and composition of extracts from flowers of Acacia mearnsii; this tree is widely cultivated because the bark is used as a raw material for various industry segments, but the flowers are not yet explored. The essential oil was evaluated by GC/FID, GC/MS, and GC/O. The antioxidant activity (DPPH and phosphomolybdenum methods) and chemical composition were investigated for a water-soluble extract, a by-product of the extraction process. 85.8% of the compounds present in the essential oil were identified, 8-heptadecene being the major compound. The main scents detected by the olfactory analysis were roast nutty, coffee, sweet, and floral. The water-soluble extract showed antioxidant activity that may be related to phenolic compounds. Results obtained from the LC-qTOF/MS analysis have shown that 25 likely flavonoids, such as naringenin, myricetin, quercetin, and rutin are present in the extract. [ABSTRACT FROM AUTHOR]

The steam distillation applied to the aerial parts of Pterocaulon polystachyum DC (Asteraceae) afforded essential oil and an aqueous residue, which is a by-product usually considered a waste. In this study, the prospects for using both essential oil and aqueous waste were investigated, showing new directions for the industrial process. The essential oil had its composition determined and showed activity against Microsporum gypseum (Bodin) Guiart & Grigorakis. The residual distillation water, which also had some activity against the same fungus, showed the presence of phenolic acids and a small amount of coumarins, molecules with interest in the pharmaceutical and food industries. In addition, the extraction curve was modeled mathematically. [ABSTRACT FROM AUTHOR]

Abstract: The Piperaceae family is represented by herbaceous plants, shrubs, and, more rarely, trees. Among the aromatic varieties of this genus, Piper hispidinervum C. DC. stands out. In this work, volatile and non‐volatile extracts from P. hispidinervum were obtained through the application of sequential extraction methods. The results of steam distillation experiments indicated that optimal conditions were achieved when the extractions were conducted at 101 kPa and an initial bed porosity of 0.91. Chemical analysis showed that safrole is the major component present in the essential oil. NMR analysis revealed the presence of 6‐methoxy eugenol for P. hispidinervum extracts obtained by supercritical fluid extraction using water as co‐solvent at 20 MPa and 313.15 K. Mathematical models adjusted well to the experimental data in all conditions investigated. The methodology proposed represents an improvement in the processing of natural products, since the same material is submitted to different technologies, obtaining different compounds with distinct properties. [ABSTRACT FROM AUTHOR]

The species of genusBaccharisspp. (Compositae) are an important natural resource in the search for new bioactive compounds. This article presents an investigation of volatile compounds of two species ofBaccharisthat are native to southern Brazil (Baccharis dentata(Vell.) G.M. Barroso andBaccharis uncinellaDC) collected in summer and autumn of 2011. The essential oils were extracted by steam distillation and analyzed by gas chromatography-mass spectrometry (GC-MS), olfactometry analysis (GC-O) and qualitative assessment of the antimicrobial potential using the indirect bioautography method againstStaphylococcus aureus,Salmonella entericasubspecieentericaserovar Choleraesuis,Pseudomonas aeruginosa,Candida albicans,Aspergillus niger,Candida parapsilosis,Cryptococcus neoformans,Rhizopus stolonifer,Fusarium solaniandAspergillus oryzae. The results demonstrated that the harvest period has an influence on the composition of the essential oils, but little influence on extraction yield. It can also be observed that the joint analysis of GC-MS and GC-O resulted in complementary information about the essential oils studied because the intensities of volatile compounds detected by both methods are significantly different. Regarding antimicrobial assays, it was found that the essential oil ofB. dentatawas effective againstS. aureus,A. niger,C. parapsilosisandR. stolonifer, whereas the essential oil ofB. uncinellawas effective againstS. aureus,S.Choleraesuis,C. albicans,A. niger,C. parapsilosis,R. stoloniferandF. solani. [ABSTRACT FROM AUTHOR]

[Display omitted] • Effects of process conditions on the H. coronarium essential oil composition. • Encapsulation of H. coronarium essential oil by nanoprecipitation. • Nanocapsules were characterized by DLS, TGA, FESEM, and TEM. • The nanoformulations remained stable for at least 90 days. • The nanoformulations promote the controlled release of components. Biopolymers are usually used in encapsulation techniques to protect natural products from degradation. The essential oil of Hedychium coronarium presents a floral scent, which justifies its use in perfumes, in addition, its antimicrobial activity may contribute to its stability as natural protectant. Thus, this work aims to investigate the Hedychium coronarium essential oil extraction by steam distillation and to enhance the physicochemical stability of this essential oil through encapsulation in polycaprolactone, also preserving its odor properties. The employed nanoprecipitation process presented a 1:3 optimal polymer/oil ratio, which yielded an average particle diameter of 159 nm. The morphology was evaluated by field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM), the essential oil encapsulation was confirmed by thermogravimetric analysis (TGA). The formulations pH remained stable for 90 days and the controlled release of the compounds was evaluated through antioxidant activity analysis. The release and diffusion of compounds from the formulations were evaluated over time and fitted with the Peppas equation. [ABSTRACT FROM AUTHOR]