Resumo A Floresta Atlântica é considerada uma rica fonte de plantas aromáticas com amplo espectro de propriedades biológicas. Na busca de novos inibidores da acetilcolinesterase (AChE) e α-glicosidase (AG), folhas de diferentes espécies de Piper localizadas na Floresta Atlântica no litoral do Paraná - Brasil, foram submetidas a hidrodestilação e seus óleos voláteis caracterizados por CG-DIC e CG-EM. A coleta ocorreu em duas estações distintas, inverno (I) e primavera (P), de 7 diferentes espécies. Sesquiterpenos foram identificados entre os compostos majoritários em todas as espécies estudadas, com dezenas de representantes. No entanto, foram observadas baixas concentrações de monoterpenos; α-pinene in Piper mosenii and P. cernuum, δ-3-carene in P. rivinoides, camphene and β-pinene in P. cernuum são exceções. Os arilpropanoides miristicina e elemicina foram identificadas em quantidades significativas em P. diospyrifolium (26.2%/P) e P. mosenii (16.4%/I), respectivamente. Para a AChE as amostras mais ativas foram P. diospyrifolium, P. aduncum e P. cernuum, com níveis de inibição > 93%. Para a AG, que se mostrou menos sensível às amostras, os candidatos mais promissores foram P. diospyrifolium e P. mosenii, ambos com níveis de inibição > 65%. Esses resultados destacam a importância das plantas nativas como fontes renováveis de novos inibidores para AChE e AG. Estudos adicionais se fazem necessários para identificar os constituintes ou frações mais ativas dos óleos voláteis selecionados.

Abstract The Atlantic Forest is regarded a rich source of aromatic plants with a broad spectrum of biological properties. The leaves of seven Piper species were collected from the Atlantic Forest domain in the coastal region of Paraná state in winter (W) and spring (S). The volatile oils were extracted from the leaves through hydrodistillation method. The volatile oils were characterized by means of GC-FID and GC-MS. Sesquiterpenes were among the major compounds in all species studied, with many dozens of representatives. However, very low concentrations of monoterpenes were observed; α-pinene in Piper mosenii and P. cernuum, δ-3-carene in P. rivinoides, camphene and β-pinene in P. cernuum are exceptions. The arylpropanoides myristicine and elemicin were found in considerable amount in P. diospyrifolium (26.2%/S) and P. mosenii (16.4%/W), respectively. These oils were also screened for inhibitory activities against acetylcholinesterase (AChE) and α-glucosidase (AG). For AChE the most active samples were P. diospyrifolium, P. aduncum and P. cernuum, with inhibiting level > 93%. For the less sensitive AG, the most promising candidates were P. diospyrifolium and P. mosenii, with inhibiting level > 65%. These results highlight the importance of native plants as renewable source of new inhibitors for AChE and AG. Further investigation is required to identify the most active constituents or fractions from the selected volatile oils.

Abstract This work describes the antimicrobial, antioxidant and anticholinesterase activities in vitro of organic extracts from fourteen seaweeds, eleven sponges, two ascidians, one bryozoan, and one sea anemone species collected along the Brazilian and Spanish coast, as well as the isolation of the diterpene (4R, 9S, 14S)-4α-acetoxy-9β,14α-dihydroxydolast-1(15),7-diene (1) and halogenated sesquiterpene elatol (2). The most promising antimicrobial results for cell wall bacteria were obtained by extracts from seaweeds Laurencia dendroidea and Sargassum vulgare var. nanun (MIC 250 μg/ml), and by the bryozoan Bugula neritina (MIC 62.5 μg/ml), both against Staphylococcus aureus. As for antimollicutes, extracts from seaweeds showed results better than the extracts from invertebrates. Almost all seaweeds assayed (92%) exhibited some antimicrobial activity against mollicutes strains (Mycoplasma hominis,Mycoplasma genitalium,Mycoplasma capricolum and Mycoplasma pneumoniae strain FH). From these seaweeds, A1 (Canistrocarpus cervicornis), A11 (Gracilaria sp.) and A4 (Lobophora variegata) showed the best results for M. pneumoniae strain FH (MIC 250 μg/ml). Furthermore, compounds 1 and 2 were also assayed against mollicutes strains M. hominis,M. genitalium,M. capricolum,M. pneumoniae strain 129 and M. pneumoniae strain FH, which showed MIC > 100 μg/ml. Antioxidant activities of extracts from these marine organisms were inactive, except for E7 (from sponge Ircinia sp.), which exhibited moderated antioxidant activities for two methods assayed (IC50 83.0 ± 0.1 μg/ml, and 52.0 ± 0.8 mg AA/g, respectively). Finally, for the anticholinesterase activity, all the 29 samples evaluated (100%) exhibited some level of activity, with IC50 < 1000 μg/ml. From these, seaweeds extracts were considered more promising than marine invertebrate extracts [A10 (IC50 14.4 ± 0.1 μg/ml), A16 (IC50 16.4 ± 0.4 μg/ml) and A8 (IC50 14.9 ± 0.5 μg/ml)]. The findings of this work are useful for further research aiming at isolation and characterization of active compounds.

This work reports the chemical composition as well as the antibacterial, antifungal and antiparasitic activities of the leaf essential oil from Piper malacophyllum. The oil was extracted by hydrodistillation and analyzed by GC-FID, GC-MS and polarimetry. Among the 28 compounds identified, (+)-camphor was the major constituent. The essential oil showed activity against most of the microorganisms tested, especially antifungal action, with a MIC of 500 µg mL-1 against Trichophyton mentagrophytes and Cryptococcus neoformans. This is the first study reporting the composition and biological properties of leaf essential oil from P. malacophyllum.

A ameixa (Prunus salicina Lindl. cv. Harry Pickstone), originária da China, é amplamente produzida e consumida em países como o Japão e o Brasil. A prática do raleio é comum na fruticultura e as frutas que são removidas são descartadas como resíduo. Como a grande maioria dos vegetais, estes frutos de raleio também contêm óleos essenciais; porém, eles não foram investigados. A extração do óleo volátil de ameixa de raleio, pelo método de hidrodestilação, obteve rendimento de 0,06% (m/m) e um total de 21 componentes foram identificados, dos quais 11 são responsáveis por 72,9% da composição total do óleo. Os principais componentes determinados por CG-DIC e CG-EM foram Z-α-bisaboleno (13,7%), ácido n-hexadecanoico (12,7%), fitol (12,7%) e β-cariofileno (10,4%).

Plum (Prunus salicina Lindl. cv. Harry Pickstone), a China indigenous fruit, is widely produced and consumed in countries such as Japan and Brazil. The practice of thinning is common in horticulture and the fruits removed are discarded as waste. Like the great majority of vegetables, these thinning discards also contain essential oils which have not been investigated until the present time. The extraction of the plum thinning discards volatile oil, through the hydrodistillation method, produced a yield of 0.06% (m/m) and a total of 21 components were identified, with 11 of them being responsible for 72,9% of the total oil composition. The major compounds determined through GC and GC-MS were Z-α-bisabolene (13.7%), n-hexadecanoic acid (12.7%), phytol (12.7%), and β-caryophyllene (10.4%).

The present work describes the use of piperonal, a derivative of the secondary metabolite safrole, for the synthesis of new 5,6-methylenedioxysubstituted indole carboxylic acids structurally related to the indol-3-yl-acetic acid (AIA, I). The route comprises six steps beginning with piperonal with an overall yield of 19%. Compound IX was tested towards its plant growth regulator properties in bioassays specific for auxine activity. The in vitro assays were performed in a germination chamber and were of two types: root growth in germinated seeds of Lactuca sativa, Cucumbis sativus and Raphanus sativus and peciole biotest using Phaseolus vulgaris.