Erlânio O. Sousa

Composição química e avaliação das atividades antibacteriana e de toxicidade dos óleos essenciais de Lantana camara L. e Lantana sp.

The essential oils from Lantana camara L. and Lantana sp. Verbenaceae, were obtained by hydrodistillation and analyzed by GC/MS. This GC/MS analysis revealed the sesquiterpenoids bicyclogermacrene (19.42%), isocaryophyllene (16.70%), valencene (12.94%) and germacrene D (12.34%) as majoritaries in the essential oil of L. camara, and bicyclogermacrene (13.93%), germacrene D (27.54 and β-caryophyllene (31.50%) in the essential oil from Lantana sp. The two essential oils were evaluated to antibacterial activity and toxicity using Artemia salina. The results revealed considerable antibacterial activity for essential oil from L. camara, meanly for Proteus vulgaris (ATCC 13315) and Escherichia coli (ATCC 25922). The essential oil of Lantana sp. showed major activity for Sthaphylococcus aureus (ATCC 10390). The evaluation of toxicity CL50 revealed results with minor values to limit pattern of 1000 μg/mL.

Composition and larvicidal activity of the essential oils of Lantana camara and Lantana montevidensis

Lantana camara Linn. and Lantana montevidensis Briq. (Verbenaceae) are native species from America s rain forest. However, these species are cultivated as ornamental plants [1]. They might be poisonous to ruminants, but are largely used in popular medicine all over the world to treat fever, flu, asthma, bronchitis, and a variety of other illnesses [2–4]. Specially in Brazil they are used to treat rheumatism and pulmonary diseases [5]. Their leaves are rich in essential oils and phenolic compounds like aesulin, quercetin, isorhamnetine, fisetine, gossypetine, tricine and aesculetine, and triterpenoids. These chemical constituents are also found in some weeds presenting allelopathic and toxic properties [6]. Aedes aegypti is responsible for yellow fever transmission and is also a vector for hemorrhaging dengue (breakbone fever), an endemic disease in Southeast Asia, Pacific islands, Africa, and America [7]. Few published works associating larval infestation levels and socioeconomical characteristics, together with dengue endemic reality and urban infestation by Aedes aegypti, are available. As larvae radication is much easier than elimination of the adult mosquito, new strategies are necessary to control larvae proliferation. The most efficient and ideal way to control dengue would be the clearance of spots favorable to growth of the mosquito. The usual way to do it involves application of synthetic products, which results in resistance development by the mosquito [8]. Several studies have targeted natural products as insecticidal agents in order to control A. aegypti larvae due to the large number of compounds and medicinal plant essential oils exhibiting larvicidal activity [9]. The results of analysis of the chemical composition of the essential oils are presented in Table 1. The volatile components of both species revealed the predominance of terpenoids and sesquiterpenoids. The main component of L. camara essential oil was found to be bicyclogermacrene (19.51%), while in L. montevidensis it was -caryophyllene (29.81%). Twenty-one components (99.11%) were identified for L. camara leaves oil, and eighteen (95.83%) for L. montevidensis, with nine chemical constituents not common to both species. The oils were assessed against Aedes aegypti larvae at the third development stage to test the larvicidal potential. Results showed that both species have larvicidal potential: Lantana camara with LD50 of 42.3 0.85 g/mL, and Lantana montevidensis with LD50 of 117 0.5 g/mL. Additionally, both values are below the standard limit of LD50 < 1000 g/mL. On the face of preliminary bioassay results against A. aegypti larvae, it might be suggested that the essential oils from these species, especially L. camara, could be regarded as natural alternatives to eradicate A. aegypti. Lantana camara and Lantana montevidensis leaves were collected in January, 2008 from the Small Aromatic and Medicinal Plants Garden of the Natural Products Research Laboratory (LPPN) at Cariri Regional University (URCA), City of Crato, Ceara State, Brazil. Exsiccates were deposited at the Dardaro de Andrade Lima Caririensis Herbarium, Biology Department, under registry No. 1662 and No. 1619, respectively for L. camara and L. montevidensis. Fresh leaves (200 g) were submitted to the hydrodistillation process in a Clevenger-like apparatus for two hours, resulting in an essential oil yield of 0.05% for L. camara and 0.07% for L. montevidensis, which were subsequently dried by anhydrous sodium sulfate (Na2SO4) and kept refrigerated until they were analyzed.

Genus Lantana: chemical aspects and biological activities

Species of the genus Lantana, belonging to the family Verbenaceae, is among the various species studied scientifically. These species are mainly native to the tropical and subtropical regions of the Americas. Currently, they are present in various countries, where they are often grown as ornamental plants. For decades, species of Lantana have been of great interest for phytochemical, biological and pharmacological studies, which have been recently intensified. The components isolated from different species of Lantana cited in the literature constitute the focus of this review. Information ethnopharmacology of Lantana, as well as the activities of their different phytochemicals are discussed. In this review, it was observed that the genus Lantana has been widely studied in relation to its phytochemical components and terpenoids, flavonoids and phenylpropanoids are the more common secondary metabolites in Lantana. All these aspects, considered in this review, allow an evaluation of the ethnopharmacological potential of Lantana for the utilization of the large biomass of these plants.

Chemical composition and synergistic interaction between aminoglycosides antibiotics and essential oil of Lantana montevidensis Briq.

The chemical composition of the essential oil from Lantana montevidensis Briq. and its antibiotic resistance modifying activity were investigated by gas chromatography/mass spectrometry (GC/MS) and microdilution assay, respectively. β-Caryophyllene (31.50%), germacrene D (27.50%) and bicyclogermacrene (13.93%) were the main constituents. The essential oil was examined for antibiotic activity alone in association with aminoglycosides against Escherichia coli Ec27 and Staphylococcus aureus Sa358. The results showed antibacterial activities of the oil and synergistic effects combined with aminoglycosides. The most expressive effect was the potentiating of amikacin on E. coli with minimal inhibitory concentration decrease (512–5 µg mL−1). The data obtained are indicative of the antibacterial activity of the essential oil of L. montevidensis and its potential in modifying the resistance of aminoglycosides analysed.

Chemical composition of the essential oils of Lantana camara L. and Lantana montevidensis Briq. and their synergistic antibiotic effects on aminoglycosides

Recently, several plants have been evaluated not only for antimicrobial activity but also for resistance-modifying action. In this work, the chemical composition and antibacterial and antibiotic-modulatory activities of the essential oils from Lantana camara L. and Lantana montevidensis Briq. were analyzed. The essential oils extracted from the leaves by hydrodistillation and analyzed by gas chromatography (GC) and gas chromatography–mass spectrometry (GC–MS) were characterized by a high percentage of sesquiterpene hydrocarbons. Among the 34 constituents identified, bicyclogermacrene (19.4%), isocaryophyllene (16.7%), valencene (12.9%) and germacrene D (12.3%) were the main constituents of the oil from L. camara, while in the oil from L. montevidensis, β-caryophyllene (31.5%), germacrene D (27.5%) and bicyclogermacrene (13.9%) predominated. The essential oils were examined for antibiotic activities alone and in combination with aminoglycosides by a microdilution assay utilizing five bacterial strains. They exhibited significant antibacterial activities, mainly against Proteus vulgaris (MIC 64 μg/mL, L. camara; MIC 128 μg/mL, L. montevidensis). Both oils also showed a synergistic effect on the activity of aminoglycoside antibiotics. Thus, the essential oils of L. camara and L. montevidensis could be used as a source of plant-derived natural products with resistance-modifying antibacterial activity.

Chemical Composition and Antibacterial Evaluation of the Essential Oil from Cymbopogon winterianus Jowitt (Gramineae)

Abstract This paper reports the chemical composition and verification of the antibacterial potential of essential oil from fresh leaves of Cymbopogon winterianus collected in the region of Cariri Ceará. The essential oil obtained by hydrodistillation showed yield of 0.5 %, and its chemical composition analysis obtained by GC-MS confirmed the presence of citronellal (61.6 %) and other constituents. Evaluation of antibacterial activity in vitro was performed by microdilution in BHI broth. We tested six strains: Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Proteus vulgaris, Shigella flexneri, and Bacillus cereus. Trial data showed that the essential oil from leaves of C. winterianus showed activity for all strains tested, and the best result with the strain of Proteus vulgaris (ATCC 13315) (MIC 128 μg/mL).

Essential oil of Alpinia zerumbet (Pers.) B.L. Burtt. & R.M. Sm. (Zingiberaceae): chemical composition and modulation of the activity of aminoglycoside antibiotics

Essential oils are new natural medicines, which have been studied extensively in recent years. In this paper, the chemical composition of the essential oil from Alpinia zerumbet leaves and its ability to modulate the activity of aminoglycoside antibiotics is reported. The essential oil was extracted by hydrodistillation and analyzed by gas chromatography (GC) and GC–mass spectrometry (GC/MS). The antibacterial activity of the essential oil alone or in association with aminoglycosides was determined by a microdilution test against twelve strains (standards and multi-resistant clinical isolates obtained from sputum and wounds), seven Gram negative and five Gram positive. The major components identified by GC/MS were 4-terpineol (32.9 ± 4.0%), 1,8-cineole (21.4 ± 1.2%), γ-terpinolene (10.0 ± 1.8%) and sabinene (7.1 ± 4.6%), with a strong predominance of monoterpenes. The results indicated that the multi-resistant clinical isolates Staphylococcus aureus 358 and Escherichia coli 27 were more sensitive to the essential oil, exhibiting minimum inhibitory concentrations (MICs) of 32 and 128 μg/mL, respectively. The essential oil was capable of enhancing the antimicrobial activity of aminoglycosides against all strains tested, except for S. aureus 358. Very significant reductions in the MICs of the antibiotics were found, with a 94% decrease in MIC of neomycin against Klebsiella pneumoniae ATCC 10031. The results obtained indicate that the A. zerumbet essential oil has a significant synergistic antibiotic effect when combined with aminoglycosides, demonstrating that its constituents may act as potentiators of the antibiotic activity of aminoglycosides.

Lantana camara L. and Lantana montevidensis (Spreng.) Briq.

Species of the genus Lantana (Verbenaceae) are among the species studied scientifically. Lantana camara L. and Lantana montevidensis (Spreng.) Briq. are shrubs present in various countries, where they are often grown as ornamental plants. They have been used in many parts of the world to treat a variety of diseases. For decades, these species have been widely studied with regards to their phytochemical components, among them terpenoids, flavonoids and phenylpropanoids being the more commonly isolated secondary metabolites. Ethnopharmacological information, isolated constituents, as well as the activities of their different phytochemicals are the focus of this chapter. All these aspects allow an evaluation of the ethnopharmacological potential of these species for the utilization of the large biomass of these plants.

Antioxidative effect and phytochemical profile of natural products from the fruits of “babaçu” (Orbignia speciose) and “buriti” (Mauritia flexuosa)

Orbignya speciosa and Mauritia flexuosa are two native palm tree species found in Brazil. Their fruits are rich in edible fixed oils, which are used for many purposes in industry, such as in the manufacture of soaps, surfactants and margarines. The aim of this work was to characterize the chemical profiles and antioxidant properties of the methanol extracts obtained from the fruits of O. speciosa and M. flexuosa. The chemical prospection was carried out using specific qualitative tests to evaluate the presence of phenolic compounds (tannins and flavonoids) in the extracts of both species. The antioxidant properties of the extracts were analyzed by the following methods: production of thiobarbituric acid reactive substances (TBARS) from phospholipids, deoxyribose degradation, radical-scavenging activity-DPPH, iron chelation assay and ferric-reducing antioxidant power (FRAP). The methanolic extracts obtained from M. flexuosa and O. speciosa presented significant antioxidant activities, although M. flexuosa presented higher antioxidant activity than O. speciosa. In conclusion, M. flexuosa and O. speciosa are important sources of antioxidant substances that may be useful in the development of new products to prevent diseases associated with oxidative stress.