Eloisa Helena A. Andrade

Database of the Amazon aromatic plants and their essential oils

The aromatic flora of the Amazon has been inventoried for 30 years. In this sense, were made over 500 field trips to collect over 2500 plants and to obtain more than 2000 essential oils and aroma concentrates, all of them submitted to GC and GC-MS. This work led to the creation of a database for the aromatic plants of the Amazon, which catalogs general information about 1250 specimens. The database has allowed the publication of the chemical composition of the oils and aromas of more than 350 species, associated with a larger number of chemical types. The essential oils of many species offer optimum conditions for economic exploitation and use in national and international market of fragrances, cosmetics, agricultural and household pesticides.

Variability in essential-oil composition of Piper marginatum sensu lato.

This paper contains data on the chemical composition of the essential oils of 22 leaf samples of Piper marginatum Jacq. collected in different areas and ecosystems of the brazilian Amazon, as well as an overview of the available literature. The species presents a large synonymy based on their different leaf characteristics and distinct scents where some of them smell like anise or very close compounds. By GC, GC/MS, and cluster analysis, we identified seven chemotypes for the leaf oils. The main components found in chemotype I were safrole (1) and 3,4‐(methylenedioxy)propiophenone (2). The chemotype II was dominated by 3,4‐(methylenedioxy)propiophenone (2) and p‐mentha‐1(7),8‐diene (10). The major compounds identified in chemotype III were 3,4‐(methylenedioxy)propiophenone (2), myristicin (3), (E)‐β‐ocimene (11), and γ‐terpinene (12). In the chemotype IV, the principal constituents were β‐caryophyllene (13), α‐copaene (14), and 3,4‐(methylenedioxy)propiophenone (2). The chemotype V was dominated by (E)‐isoosmorhizole (6), (E)‐anethole (8), and isoosmorhizole (7). The main compounds found in the chemotype VI were 2‐methoxy‐4,5‐(methylenedioxy)propiophenone (4), methoxy‐4,5‐(methylenedioxy)propiophenone isomer 5, and (E)‐isoosmorhizole (6). The major constituents in chemotype VII were β‐caryophyllene (13), bicyclogermacrene (15), and (E)‐asarone (9).

Molluscicidal and leishmanicidal activity of the leaf essential oil of Syzygium cumini (L.) SKEELS from Brazil.

The chemical composition and biological potential of the essential oil extracted from Syzygium cumini leaves collected in Brazil were examined. GC/MS Analyses revealed a high abundance of monoterpenes (87.12%) in the oil. Eleven compounds were identified, with the major components being α‐pinene (31.85%), (Z)‐β‐ocimene (28.98%), and (E)‐β‐ocimene (11.71%). To evaluate the molluscicidal effect of the oil, it was tested against Biomphalaria glabrata and the LC50 obtained was 90 mg/l. The essential oil also showed significant activity against Leishmania amazonensis, with an IC50 value equal to 60 mg/l. In addition, to evaluate its toxicity towards a non‐target organism, the essential oil was tested against Artemia salina and showed a LC50 of 175 mg/l. Thus, the essential oil of S. cumini showed promising activity as a molluscicidal and leishmanicidal agent and might be valuable in combating neglected tropical diseases such as schistosomiasis and leishmaniasis. Further research is being conducted with regard to the purification and isolation of the most active essential‐oil compounds.

Plant sources of amazon rosewood oil

The aim of this study is to reevaluate the plant sources of the Amazon rosewood oil which have been named Aniba rosaeodora Ducke and Aniba duckei Kosterm. There is some disagreement on the exact botanical status of these species. Some Lauraceae specialists analyzing available material from both species concluded that there is no basis for regarding them as different. Based on our results we are confirming that the chemical composition of both species is quite different from that previously reported. So we are suggesting to bring back the previous botanical rosewood status as proposed by Adolph Ducke.

Antioxidant capacity and biological activity of essential oil and methanol extract of Hyptis crenata Pohl ex Benth

The essential oils of fresh and dried leaves and fine stems of Hyptis crenata furnished the following yields: 1.4% and 0.9%. The main volatile constituents were ±-pinene (22.0%; 19.5%), 1,8-cineole (17.6%; 23.2%), ²-pinene (17.0%; 13.8%), camphor (4.7%; 11.6%), limonene (5.4%; 4.4%) and ³-terpinene (3.5%; 2.4%), totalizing more than 70% in the oils. The DPPH radical scavenging activity (EC50, 16.7 + 0.4 µg/mL) of the methanol extract was comparable to BHT (19.8 ± 0.5 µg/mL) showing a significant antioxidant activity. The oils showed low activities. The amount of total phenolics (TP, 373.0 + 15.9 mg GAE/g) and trolox equivalent (TEAC, 226.8 + 0.5 mg TE/g) confirmed the antioxidant activity of the methanol extract that can be attributed to the presence of polar phenolic compounds. In the brine shrimp bioassay the lethal concentrations (LC50) for the oil and methanol extract were 6.7 + 0.2 µg/mL and 13.0 + 3.7 µg/mL, respectively, providing important evidence of their biological activities.

Molluscicidal and larvicidal activities and essential oil composition of Cymbopogon winterianus

Abstract Context. Cymbopogon winterianus Jowitt ex Bor (Poaceae), known as citronella grass, is an aromatic herbaceous plant and the essential oil extracted from this grass is used in cosmetics, perfumes, hygiene and cleanliness products worldwide. Objective: This study investigated the composition and molluscicidal and larvicidal activities of the essential oil of C. winterianus cultivated in North Brazil. Materials and methods: The oil was obtained by hydrodistillation, analyzed by gas chromatography (GC) and GC-mass spectrometry and then its molluscicidal and larvicidal activities against snails (Biomphalaria glabrata) and hatched larvae of Artemia salina, respectively, were evaluated at concentrations from 10 to 1000 mg/L. Results: The main constituents of oil were citronellal (26.5%), geraniol (16.2%), elemol (14.5%) and citronellol (7.3%). The molluscicidal test revealed significant lethal concentration (LC) values (LC90 = 97.0 mg/L, LC50 = 54.0 mg/L and LC20 = 22.0 mg/L), indicating the presence of molluscicidal compounds in the oil. In addition, the oil showed moderate larvicidal activity (LC50 = 181.0 mg/L) against the larvae of A. salina, which could justify its use in the aquatic environment without affecting other living organisms. Discussion and conclusion: The results suggest that the oil of C. winterianus could be an effective alternative to control schistosomiasis, with an average margin of safety to other living organisms that coexist with snails.

Chemical composition and acaricide activity of an essential oil from a rare chemotype of Cinnamomum verum Presl on Rhipicephalus microplus (Acari: Ixodidae)

The Essential Oils (EOs) from the leaves of species Cinnamomum verum J. Presl are used in the pharmaceutical industry for their numerous biological activities. Currently, the main compound of C. verum EO is eugenol which has acaricidal activity; however, a rare chemotype with benzyl benzoate as the main component can be found. Benzyl benzoate is recognized as an acaricide; however, studies of the C. verum EOs benzyl benzoate chemotype on Rhipicephalus microplus were not reported. The aim of this study was to evaluate the acaricide activity of an EO from a rare chemotype of C. verum, as well as purified benzyl benzoate, against larvae and engorged females of R. microplus resistant to amidines and pyrethroids. The EO was extracted from C. verum leaves and the compounds present were identified using a gas phase chromatograph coupled to a mass spectrometer. Efficacy against R. microplus was assessed by the larval packet and the engorged female immersion tests. A rare chemotype of C. verum was found to produce EOs with benzyl benzoate (65.4%) as the main compound. The C. verum essential oil was 3.3 times more efficient on the R. microplus larvae than was benzyl benzoate. However, no differences were found on the R. microplus engorged females. This is the first report regarding the acaricidal activity of C. verum with chemotype benzyl benzoate, and this compound showed acaricidal activity on R. microplus larvae.

Essential oil composition of Croton palanostigma Klotzsch from north Brazil

Os oleos essenciais das folhas, ramos finos, galhos, cascas do caule e frutos de Croton palanostigma foram analisados por CG e CG-EM. Os componentes principais determinados no oleo das folhas foram linalol (25,4%), (E)-cariofileno (21,0%), metileugenol (17,2%) e β-elemeno (6,0%); no oleo dos ramos finos foram α-pineno (41,4%), limoneno (29,0%), sabineno (11,5%) e β-pineno (5,7%); no oleo dos galhos foram metileugenol (24,1%), (E)-metilisoeugenol (15,3%), α-pineno (11,2%) e (E)-cariofileno (8,5%); no oleo das cascas do caule foram a-pineno (31,6%), metileugenol (25,6%) e (E)-metilisoeugenol (23,7%); e no oleo dos frutos foram linalol (42,7%), metileugenol (16,3%) e β-elemeno (6,4%). Analise estatistica mostrou que as folhas e os frutos apresentam significante similaridade entre si, assim como os galhos e as cascas do caule. Adicionalmente, o oleo obtido das cascas do caule possui elevada atividade larvicida sobre Artemia salina (CL50, 3,71 ± 0,01 mg mL-1).

Essential Oil Composition of Piper demeraranum (Miq.) C. DC

Abstract Four samples of aerial parts of Piper demeraranum were collected in the municipalities of Belém and Ananindeua, Pará state, brazilian Amazon. The samples were hydro distilled and the resulting oils were analyzed by GC and GC-MS. Seventy-four compounds were identified in the oils. The oils of samples 1–4 showed very similar chromatographic profiles presenting limonene (20.2%, 31.0%, 40.3% and 30.6%), sabinene (12.9%, 17.0%, 22.7% and 18.2%), β-pinene (7.7%, 8.2%, and 14.4% and 10.7%) and α-pinene (7.3%, 6.1%, 12.3% and 7.6%) as their main constituents. The other components were found in minute amounts in the essential oil samples. Based in these results we are attributing the occurrence of the same specimen of Piper demeraranum for the different collected samples and at diferent collection sites.

Essential Oil Composition of Piper Anonofolium (Kunth) C. DC

Abstract Seven samples of aerial parts of Piper anonifolium were collected in the municipalities of Santa Isabel, Ananindeua and Bujaru, Pará state, brazilian Amazon. The samples were hydrodistilled and analysed by GC and GC-MS. The oils of samples 5, 6 and 7 showed very similar chromatographic profiles presenting α-pinene (45.5%, 45.7% and 41.1%), β-pinene (17.7%, 17.2% and 17.8%) and limonene (7.1%, 8.4% and 6.1%) as their main constituents. The oil of sample 1 was dominated by α-pinene (53.1%) and β-pinene (22.9%), followed by minute amount of limonene (1.7%), resembling the oils of samples 5, 6 and 7 . The main constituents found in the oils of samples 2 and 4 were α-pinene (40.9% and 41.8%), β-pinene (18.8% and 18.6%), limonene (7.4% and 8.5%) and δ-2-carene (7.7% and 8.0%), presenting a small difference in comparison with the oils of samples 1, 5, 6 and 7. The oil of sample 3 was quite different concerning with the other oils, where the principal components were α-eudesmol (33.5%), ishwarane (19.1%), germacrene D (9.6%), α-pinene (7.3%) and limonene (5.9%). We imputed the different collection sites for the reason of the distinguished oil composition of Piper anonifolium.