Terpene Synthase Gene Family in Chinese Chestnut (Castanea mollissima BL.) Harbors Two Sesquiterpene Synthase Genes Implicated in Defense against Gall Wasp Dryocosmus kuriphilus.

Chinese chestnut (Castanea mollissima BL.) is a well-known fruit tree that has been cultivated in East Asia for millennia. Leaves and buds of the plant can become seriously infested by the gall wasp Dryocosmus kuriphilus (GWDK), which results in gall formation and associated significant losses in fruit production. Herbivore-induced terpenes have been reported to play an important role in plant-herbivory interactions, and in this study, we show that upon herbivory by GWDK, four terpene-related compounds were significantly induced, while the concentrations of these four compounds in intact buds were relatively low. Among these compounds, (E)-nerolidol and (E, E)-α-farnesene have frequently been reported to be involved in plant herbivory defenses, which suggests direct and/or indirect functions in chestnut GWDK defenses. Candidate terpene synthase (TPS) genes that may account for (E)-nerolidol and (E, E)-α-farnesene terpene biosynthesis were characterized by transcriptomics and phylogenetic approaches, which revealed altered transcript levels for two TPSs: CmAFS, a TPS-g subfamily member, and CmNES/AFS, a TPS-b clade member. Both genes were dramatically upregulated in gene expression upon GWDK infestation. Furthermore, Agrobacterium tumefaciens-mediated transient overexpression in Nicotiana benthamiana showed that CmAFS catalyzed the formation of (E, E)-α-farnesene, while CmNES/AFS showed dual (E)-nerolidol and (E, E)-α-farnesene synthase activity. Biochemical assays of the recombinant CmAFS and CmNES/AFS proteins confirmed their catalytic activity in vitro, and the enzymatic products were consistent with two of the major volatile compounds released upon GWDK-infested chestnut buds. Subcellular localization demonstrated that CmAFS and CmNES/AFS were both localized in the cytoplasm, the primary compartment for sesquiterpene synthesis. In summary, we show that two novel sesquiterpene synthase genes CmAFS and CmNES/AFS are inducible by herbivory and can account for the elevated accumulation of (E, E)-α-farnesene and (E)-nerolidol upon GWDK infestation and may be implicated in chestnut defense against GWDK herbivores.

Chemical Composition and Biological Activities of Hedychium coccineum Buch.-Ham. ex Sm. Essential Oils from Kumaun Hills of Uttarakhand.

Hedychium coccineum Buch. Ham. ex Sm. is a perennial rhizomatous herb belonging to the family Zingiberaceae. The aim of the present study was to compare the chemical composition and biological activities of H. coccineum rhizome essential oil (HCCRO) and H. coccineum aerial part essential oil (HCCAO). The plant material was subjected to hydro-distillation using Clevenger's apparatus in order to obtain volatile oil and analyzed for its chemical constituents using GC-MS. The comparative study of the rhizome and aerial part essential oils of H. coccineum displayed that (E)-nerolidol (15.9%), bornyl acetate (13.95%), davanone B (10.9%), spathulenol (8.9%), and 1, 8-cineol (8.5%) contributed majorly to the HCCRO, while 7-hydroxyfarnesen (15.5%), α-farnesene (11.1%), α-pinene (10.9%), spathulenol (7.7%), and ß-pinene (6.8%) were present as major constituents in the HCCAO. Both the essential oils were studied for their biological activities, such as nematicidal, insecticidal, herbicidal, antifungal, and antibacterial activities. The essential oils exhibited significant nematicidal activity against Meloidogyne incognita, insecticidal activity against Spodoptera litura, and moderate herbicidal activity against R. raphanistrum sub sp. sativus, and good antifungal activity against Fusarium oxysporum and Curvularialunata. Essential oils were also tested for antibacterial activity against Staphylococcus aureus and Salmonella enterica serotype Typhi. Both oils showed good to moderate activity against the tested pathogens. The significant nematicidal, insecticidal, herbicidal, antifungal, and antibacterial activities of both the essential oils might be helpful for the development of environmentally friendly pesticides that could be an alternative to synthetic pesticides in the future.

Chemical composition and antifungal activity of Zanthoxylum riedelianum stem bark essential oil.

The phytopathogenic fungi Sclerotinia sclerotiorum and Rhizopus stolonifer infect different crop plants. Essential oils have been used as an alternative to chemical control methods. Therefore, the objective of this study was to analyze the essential oil chemical composition of the stem bark of Zanthoxylum riedelianum (ZREO) and evaluate its antifungal potential. The ZREO obtained by hydrodistillation was analyzed using gas chromatography coupled to mass spectrometry and evaluated for in vitro antifungal activity. The major components identified in the chemical analysis were E-nerolidol (67.21%), α-selinene (14.94%), and ß-selinene (7.41%). The antifungal potential of ZREO against S. sclerotiorum and R. stolonifer was detected at all concentrations evaluated in a dose-dependent manner. The best results were against R. stolonifer, with the concentration of 150 µLmL-1 inhibiting more than 80% of mycelial growth. On the basis of the current knowledge, this study describes for the first time the chemical composition and their antifungal activity.

Functional Characterization of a New Bifunctional Terpene Synthase LpNES1 from a Medicinal Plant Laggera pter odonta.

Laggera pterodonta, known in China as 'Choulingdan' for its stimulous odor, has long been used as traditional herbal medicine. The essential oil of L. pterodonta, which exhibits various pharmacological activities, is a rich resource of monoterpenes and sesquiterpenes. To date, however, the terpene synthases responsible for their production remain unknown. In present study, a new terpene synthase gene (LpNES1) was identified from L. pterodonta, transcript level of which was significantly upregulated in response to methyl jasmonate treatment. Recombinant LpNES1 could synthesize (E)-nerolidol and minor ß-farnesene from farnesyl diphosphate and linalool from geranyl diphosphate in vitro. Whereas, only sesquiterpenes including (E)-nerolidol and minor ß-farnesene were released when LpNES1 was reconstituted in yeast, even coexpressed with a geranyl diphosphate synthase (ERG20WW). Combined with subcellular localization experiment, the result indicated that the cytosol-targeted LpNES1 was responsible for (E)-nerolidol biosynthesis exclusively in L. pterodonta. Additionally, the expression level of LpNES1 gene was more prominent in floral buds than that in other tissues. LpNES1 characterized in present study not only lays the molecular foundation for sesquiterpene biosynthesis of L. pterodonta, but provides a key element for further biosynthesis of bioactive compound in microbes.

Mineral Content, Antioxidant Activity and Essential Oil of Allophylus edulis (A. St.-Hil., A. Juss. & Cambess.) Radlk. Leaves: Plant from South American Biodiversity.

Allophylus edulis (A. St.-Hil., A. Juss. & Cambess.) Radlk. (Sapindaceae) is an edible plant from the South American biodiversity that is a potential source of bioactive compounds. The mineral content and antioxidant activity of Allophylus edulis leaves were investigated, as well as the composition and the antioxidant activity of the essential oil. The mineral content was determined by ICP - OES and the antioxidant assays were assessed by ABTS, DPPH and FRAP. The essential oil was obtained by hydrodistillation and analyzed by GC/MS. Calcium, potassium, phosphorus, sulfur, and magnesium were the main minerals found in A. edulis leaves. Of the toxic metals that were present, a low level of aluminum was detected. The essential oil of A. edulis has (E)-nerolidol as major compound and both, the leaves, and the essential oil isolated from the leaves have antioxidant potential. These findings could provide a framework for developing new food and non-food products with A. edulis leaves.

Methyl Eugenol, 1,8-Cineole and Nerolidol Rich Essential Oils with their Biological Activities from three Melaleuca Species Growing in Tarai Region of North India

Abstract The essential oils from the fresh leaves of three Melalecua spp. viz; Melaleuca leucadendron (L.) Melaleuca linariifolia Sm. and Melaleuca bracteata F. Muell. growing in Tarai region of North India were analyzed by a combination of gas chromatography/mass spectrometry. The analysis revealed the presence of several constituents of industrial and pharmacological importance. M. leucadendron essential oil was found to be dominated by E-nerolidol (85.7%) rich chemotype. 1,8-cineole (61.1%) along with significant presence of α-terpineol (12.3%), α-pinene (4.0%), β-myrcene (3.8%), and E-caryophyllene (1.7%) were identified in the essential oil from M. linariifolia Similarly M. bracteata was dominated by the presence of phenylpropanoids viz; methyl eugenol (74.8%) and methyl cinnamate (8.0%). The essential oils were studied for their in-vitro antioxidant, anti-inflammatory and antimicrobial potential. All the oils revealed potential antioxidant activity with maximum in M. bracteata essential oil. All the oils exhibited significant antibacterial activity against Bacillus megaterium, Staphylococcus aureus, Escherichia coli,Salmonella typhimurium and anti-fungal activity against phytopathogenic fungi Fusarium oxysporum, Sclerotinia sclerotiorum, Exserohilum turcicum and Curvularia lunata. The observations from present study suggest further cultivation of Melaleucas and its commercialization as industrial crops.

Chemical Composition and Antioxidant Activity of Essential Oils from Populations of Baccharis dracunculifolia DC. in Southern Brazil

HIGHLIGHTS Essential oils from populations of B. dracunculifolia were investigated. β-pinene and (E)-nerolidol were the main compounds in B. dracunculifolia populations. The difference in the chemical profile of the essential oils is quantitative only. There is a negative correlation between the antioxidant activity and spathulenol.

Abstract Baccharis dracunculifolia DC. is a Brazilian native plant, presenting wide chemical diversity and numerous pharmaceutical and industrial applications. This research assessed the yield, antioxidant activity and the chemical similarity of essential oils from 10 populations of B. dracunculifolia in the state of Paraná, southern Brazil. The extraction of the volatile compounds was carried out by hydrodistillation, the chemical composition was determined by GC/FID and GC/MS and the antioxidant activity by the DPPH method. The essential oil yield of wild B. dracunculifolia populations ranged from 0.14 to 0.87%. The oils were predominantly composed of oxygenated sesquiterpenes (34.16 - 51.01%), monoterpene hydrocarbons (18.02 - 46.17%) and sesquiterpenes hydrocarbons (9.60 - 17.70%). The major compounds found in all populations were β-pinene (7.65 - 29.8%) and (E)-nerolidol (9.11 - 21.68%). Essential oil solutions (20%) from different populations presented antioxidant capacity ranging from 27.78 to 91.67%. A negative correlation was found between the antioxidant activity and spathulenol (r = -0.696). Multivariate analyses separated the populations into three groups: (1) low concentrations of α-pinene (2.02 - 2.06%), (2) high concentrations of α-pinene (4.17 - 4.61%) and β-pinene (22.54 - 29.80%), and (3) intermediate concentrations of α-pinene (2.38 - 3.31%), β-pinene (12.77 - 19.03%) and spathulenol (6.02 - 9.06%).

Indian Sarsaparilla (Hemidesmus indicus): Recent progress in research on ethnobotany, phytochemistry and pharmacology.

ETHNOPHARMACOLOGICAL RELEVANCE: Hemidesmus indicus (L.) R. Br. ex Schult. (Apocynaceae) is widely used in traditional medicine in the different parts of the Indian subcontinent due to the various biological activities attributed to its different parts, especially the roots. It has traditionally been used for treating snakebites, scorpion stings, diabetes, urinary diseases, dyspnea, menorrhagia, oligospermia, anorexia, fever, abdominal colic and pain, dysentery, diarrhea, cough, rheumatism, headache, inflammation, pyrosis, skin diseases, leprosy, sexually transmitted diseases and cancer. In Ayurveda, the plant is used in the treatment of bone-loss, low body weight, fever, stress, topical wound and psoriasis. Besides, Ayurvedic literature also depicts its use as anti-atherogenic, anti-spasmodic, memory enhancing, immunopotentiating and anti-inflammatory agents. AIM OF THE STUDY: In this review, we aim to present a comprehensive update on the ethnopharmacology, phytochemistry, specific pharmacology, and toxicology of H. indicus and its bioactive metabolites. Possible directions for future research are also outlined in brief. MATERIALS AND METHODS: Popular and widely used international databases such as PubMed, Scopus, Science Direct, Google Scholar and JSTOR were searched and traditional literature were consulted using the various search strings to retrieve a number of citations related to the ethnopharmacology, biological activity, toxicology, quality control and phytochemistry of H. indicus. All studies on the ethnobotany, phtochemistry, pharmacology, and toxicology of the plant up to 2019 were included in this review. RESULTS: H. indicus has played an important role in traditional Indian medicine (including Ayurveda) and also in European medicine. The main pharmacological properties of H. indicus include hepatoprotective, anti-cancer, anti-diabetic, antioxidant, neuroprotective, anti-ophidian, cardioprotective, nephroprotective, anti-ulcerogenic, anti-inflammatory, and antimicrobial properties. Phytochemical evaluations of the root have revealed the presence of aromatic aldehydes and their derivatives, phenolics, triterpenoids and many other compounds, some of which were attributed to its bioactivity. This review also compiles a list of Ayurvedic formulations and commercial preparations where H. indicus has been used as an active ingredient. We have included the critical assessment of all the papers cited in this manuscript based on experimental observation and other important points which reflect the loop-holes of research strategy and ambiguity in the papers reviewed in this manuscript. CONCLUSIONS: The study presents an exhaustive and updated review on the traditional, pharmacological and phytochemical aspects of H. indicus with notes on its quality control and toxicological information. Although the crude extracts of H. indicus exhibit an array of pharmacological activities, it is high time to identify more active phyto-constituents by bioactivity-guided isolation besides elucidating their structure-activity relationship. More designed investigations are needed to comprehend the multi-target network pharmacology, to clarify the molecular mode of action and to ascertain the efficacious doses of H. indicus. Moreover, H. indicus is not fully assessed on the basis of its safety and efficacy on human. We hope this review will compile and improve the existing knowledge on the potential utilization of H. indicus in complementary and alternative medicine.

(3R,6E)-nerolidol, a fertility-related volatile secreted by the queens of higher termites (Termitidae: Syntermitinae).

The queens of advanced social insects maintain their reproductive monopoly by using exocrine chemicals. The chemistry of these "queen pheromones" in termites is poorly known. We show that primary queens of four higher termites from the subfamily Syntermitinae (Embiratermes neotenicus, Silvestritermes heyeri, Labiotermes labralis, and Cyrilliotermes angulariceps) emit significant amounts of the sesquiterpene alcohol (E)-nerolidol. It is the dominant analyte in queen body washes; it is present on the surface of eggs, but absent in kings, workers, and soldiers. In E. neotenicus, it is also produced by replacement neotenic queens, in quantities correlated with their fertility. Using newly synthesised (3R,6E)-nerolidol, we demonstrate that the queens of this species produce only the (R) enantiomer. It is distributed over the surface of their abdomen, in internal tissues, and in the haemolymph, as well as in the headspace of the queens. Both (R) and (S) enantiomers are perceived by the antennae of E. neotenicus workers. The naturally occurring (R) enantiomer elicited a significantly larger antennal response, but it did not show any behavioural effect. In spite of technical difficulties encountered in long-term experiments with the studied species, (3R,6E)-nerolidol remains among eventual candidates for the role in queen fertility signalling.

Chemical composition, anti-nociceptive and anti-inflammatory activities of essential oil of Bougainvillea glabra.

ETHNOPHARMACOLOGICAL RELEVANCE: Bougainvillea glabra is widely used in Nigeria for the treatment of inflammatory-related conditions, and as remedy for pain ailments. AIM OF THE STUDY: Considering the lack of scientific studies focused on chemical constituents and pharmacological activity of B. glabra essential oil, this work was designed to characterize the volatile compounds and evaluate the anti-inflammatory and anti-nociceptive properties ascribed to this plant species. MATERIALS AND METHODS: The essential oil was extracted from the leaf of B. glabra by hydrodistillation in an all glass Clevenger-type apparatus and characterized by gas chromatography (GC-FID) and gas chromatography-mass spectrometry (GC-MS) on HP-5 column. The anti-inflammatory property of the essential was established by measurement of carrageenan induced rat paw edema while the anti-nociceptive activity was determined by hot plate test, according to established procedures. RESULTS: The essential oil was obtained in a yield of 0.08% (v/w) calculated on dry weight basis. A total of 11 compounds representing 96.2% of the oil contents were identified by GC/MS. The main constituents of the essential oil were (E)-nerolidol (31.4%), (E)-ß-ionone (10.3%) and linalool (10.1%). The anti-nociceptive property of the essential oil was statistically significant p < 0.001 at all doses of when compared to the control while exhibiting an activity in tandem with the standard drug. For the 1st and 2nd h, at doses of 100 and 200 mg/kg, the anti-inflammatory activity was statistically very significant (p < 0.001), while at 3rd h the activity declined (p < 0.01) at a dose of 200 mg. The activity was non-significant at the 4th h experimental duration. CONCLUSIONS: This is first report on the chemical constituents and biological activity of essential oil of B. glabra from Nigeria. Overall, the results herein presented sustain and strengthen the anti-nociceptive and anti-inflammatory properties traditionally ascribed to B. glabra.

First record of the chemical composition of essential oil of Piper bellidifolium, Piper durilignum, Piper acutilimbum and Piper consanguineum from the Brazilian Amazon forest / Primeiro registro da composição química de óleos essenciais de Piper bellidifolium, Piper durilignum, Piper acutilimbum e Piperconsanguineumda Floresta Amazônica no Brasil

Piper bellidifolium, Piper durilignum, Piper acutilimbum and Piper consanguineum are bushes that occur in the Amazon and are morphologically similar. With the aim of analyzing the chemical profile of the volatile constituents of these species, essential oils from the leaves were obtained through steam distillation and analyzed using gas chromatography-flame ionization detection (GC-FID) and gas chromatograph coupled to a mass spectrometer (GC-MS). The chemical analysis enabled the identification of 95 compounds representing 96.3 ± 0.6% of the P. bellidifolium oil, 95.5 ± 0.71% of the P. durilignum oil, 98.0 ± 1.0% of the P. acutilimbum oil and 96.1 ± 2.1% of the P. consanguineum oil. Although sesquiterpenes were the predominant chemical class in the oils of the four species, qualitative and quantitative differences were found in their chemical composition. The major constituents were (E)-nerolidol (20.3 ± 0.4%) in the P. bellidifolium oil, germacrene D (11.1 ± 0.3%) in the P. durilignum oil, and -eudesmol in both the P. consanguineum (18.6 ± 0.5%) and P. acutilimbum (7.5 ± 0.4%) oils. Despite their morphological similarity, a principal component analysis (PCA) of the GC-MS data clearly separated the four species according to the chemical profile of the essential oil extracted from their leaves.

Piper bellidifolium, Piper durilignum, Piper acutilimbum e Piper consanguineum são arbustos que ocorrem na Amazônia e são morfologicamente similares. Com o intuito de analisar o perfil químico dos constituintes voláteis dessas espécies, óleos essenciais das folhas foram obtidos por hidrodestilação e analisados por cromatografia gasosa - detector por ionização de chama (CG-FID) e cromatografia gasosa acoplada a espectrometria de massa (CG-EM). A análise química permitiu identificar 95 compostos, representando 96.3 ± 0.6% do óleo de P. bellidifolium; 95.5 ± 0.71% de P. durilignum; 98.0 ± 1.0% de P. acutilimbum e 96.1 ± 2.1% de P. consanguineum. Apesar dos óleos das quatro espécies terem sesquiterpeno como classe química predominante, diferenças qualitativas e quantitativas em sua composição química foram observadas. Os principais componentes encontrados foram: (E)-nerolidol (20.3 ± 0.4%) em P. bellidifolium; germacreno D (11.1 ± 0.3%) em P. durilignum; e -eudesmol nos óleos de P. consanguineum (18.6 ± 0.5%) e P. acutilimbum (7.5 ± 0.4%). Apesar da similaridade morfológica entre as espécies, uma análise de componentes principais (PCA) dos dados de CG-EM claramente separou as quatro espécies quanto ao perfil químico do óleo essencial extríado de suas folhas.

Seasonal chemical composition of an unexplored essential oil of Eugenia brevistyla / Composición química estacional de un aceite esencial no explorado de Eugenia brevistyla

This study describes the qualitative and quantitative seasonal analysis of the essential oils from an unexplored plant Eugenia brevistyla, native from Brazilian Atlantic Rain Forest and Semidecidual Forest. Analysis by GC-FID and GC-MS allowed the identification of 28 compounds. The largest fraction corresponds to oxygenated sesquiterpenes in all seasons. The major compound was E-nerolidol in all seasons, being higher in winter (83.14%) and lower in spring (69.6%). The second major compound was byciclogermacrene in the spring and in the summer essential oils. Alloaromadendrene and spathulenol were the second major compounds in autumn and winter, respectively. Sesquiterpenes hydrocarbons showed higher variation along the year (58%) than oxygenated sesquiterpenes (2%). No monoterpenes were found in the analyzed essential oils.

Este estudio describe el análisis estacional cualitativo y cuantitativo del aceite esencial de la planta inexplorada Eugenia brevistyla, nativa de la Selva Tropical Atlántica dey del Bosque Semidecidual de Brasil. El análisis por GC-FID y GC-MS permitió la identificación de 28 compuestos. La fracción más grande corresponde a sesquiterpenos oxigenados en todas las estaciones. El compuesto principal fue E-nerolidol en todas las estaciones, siendo más alto en invierno (83.14%) y más bajo en la primavera (69.6%). El segundo compuesto principal fue biciclogermacreno en los aceites esenciales de la primavera y del verano. El aloaromadendreno y el espatulenol fueron los segundos compuestos principales en otoño e invierno, respectivamente. Los hidrocarburos sesquiterpénicos mostraron una mayor variación a lo largo del año (58%) que los sesquiterpenos oxigenados (2%). No se encontraron monoterpenos en los aceites esenciales analizados.

Antimicrobial and antioxidant activity of the essential oil from the Carpathian Thymus alternans Klokov.

The genus Thymus includes several species that are used as flavouring, food preservative as well as in cosmetics. Their secondary metabolites have been extensively studied for pharmacological effects. Nonetheless, some species are neglected and deserve to be explored for chemical composition and biological activities. This is the case with Thymus alternans, a Carpathian bush used as a food additive and for the preparation of a traditional herbal medicine. In this work, we have analysed the chemical composition of T. alternans essential oil by GC and GC-MS and evaluated its antimicrobial and antioxidant activity by disc diffusion, DPPH, ABTS and FRAP methods, respectively. Results showed that T. alternans belongs to the nerolidol chemotype, being rich of this sesquiterpene alcohol (15.8%) which might contribute to the antimicrobial (particularly effective on C. albicans growth) and antioxidant (weak inhibition on ABTS radical and reducing power) activities observed.

Cloning, expression and functional characterization of two sesquiterpene synthase genes from moso bamboo (Phyllostachys edulis).

The purpose of this work was to characterize the functions of two sesquiterpene synthase genes from moso bamboo (Phyllostachys edulis). Two novel sesquiterpene synthase genes, belonging to the Tpsa subfamily, were isolated from moso bamboo. MoTPS2 was 1641 bp in length and encoded a protein of 63 kDa, whereas MoTPS6 was 1626 bp in length, encoded protein 62.4 kDa. Both genes were expressed in Pichia pastoris for heterologous expression, and protein contents reached 0.243 µg µL(-1) for MoTPS2 and 0.088 µg µL(-1) for MoTPS6. The soluble enzymes were catalytically active, and capable of converting farnesyl pyrophosphate to two distinct sesquiterpene compounds. The MoTPS2 gene encoded a farnesol synthase which was responsible for the production of (E, E)-farnesol. MoTPS6 showed nerolidol synthase activity, catalyzing the formation of (E)-nerolidol. Functional characterization of both MoTPSs should prove beneficial for future research into large-scale fermentation of sesquiterpenes.

Essential oil composition and biological activity from Artemisia caerulescens subsp. densiflora (Viv.) Gamisans ex Kerguélen & Lambinon (Asteraceae), an endemic species in the habitat of La Maddalena Archipelago.

The purpose of this study was to investigate the composition of the essential oil obtained from a population of Artemisia caerulescens subsp. densiflora growing in Razzoli, an island in the La Maddalena Archipelago (Sardinia, Italy). A. caerulescens sups. densiflora Viv. (Asteraceae), a wild herb, seldom studied in the Mediterranean, represents one of the many rare endemic species growing in North Sardinia. The essential oil composition was analysed by means of GC/MS analysis, which showed davana ethers as the major volatile components, accounting together for 17.5%, followed by (E)-nerolidol (4.5%), ß-oplopenone (3.3%), cis-sabinene hydrate (5.2%) and terpinen-4-ol (4.7%). The oil was tested for antioxidant activity by means of DPPH test, inhibition of lipid oxidation test and hypochlorous acid test, which showed a quite interesting scavenger capacity. For the first time, we reported the cytotoxic activity of the essential oil of A. caerulescens subsp. densiflora, against three human tumour cell lines (A375, MDA-MB231 and HCT116), with IC50 values in the range 5.20-7.61 µg/mL, which deserved further studies to support its use as chemopreventive agent. Finally, the antimicrobial activity of the essential oil, displayed on a panel of human pathogens, was very low.

Evaluation of mutagenic and antimicrobial properties of brown propolis essential oil from the Brazilian Cerrado biome.

Biological, and particularly antimicrobial, activities have been demonstrated for the essential oil of propolis samples worlwide, yet their mutagenic effects remain unknown. To correlate antimicrobial effects with mutagenic risks, the present study evaluated the antifungal and antibacterial activities of the essential oil obtained from brown propolis collected from the Cerrado biome in Midwest Brazil (EOP), testing it against nine pathogenic microorganisms. Evaluation of mutagenic potential was based on the somatic mutation and recombination test (SMART) performed on wing cells of standard (ST) and high-bioactivation (HB) crosses of Drosophila melanogaster. EOP was extracted by hydrodistillation, and sesquiterpenes were characterized by GCâ¿¿MS as its major constituents. The crude oil proved active against Cryptococcus neoformans and Enterococcus faecalis, as did two of its major constituents, spathulenol and (E)-nerolidol â¿¿ the latter being also active against Staphylococcus aureus â¿¿ isolated using chromatographic procedures. No significant increase in the number of somatic mutations was observed in the offspring of ST or HB crosses â¿¿ the latter exhibiting enhanced levels of metabolizing enzymes of the cytochrome P450 type â¿¿ treated with 0.05%, 0.1%, and 0.2% EOP. These findings revealed no mutagenic activity of EOP, even when tested against the HB strain, and demonstrated that its antimicrobial activities are not associated with DNA damage induction (investigated with SMART), suggesting the potential of EOP as a natural preservative.

Volatile interaction between undamaged plants affects tritrophic interactions through changed plant volatile emission.

Volatile interactions between unattacked plants can lead to changes in their volatile emissions. Exposure of potato plants to onion plant volatiles results in increased emission of 2 terpenoids, (E)-nerolidol and TMTT. We investigated whether this is detectable by the ladybird Coccinella septempunctata. The odor of onion-exposed potato was significantly more attractive to ladybirds than that of unexposed potato. Further, a synthetic blend mimicking the volatile profile of onion-exposed potato was more attractive than a blend mimicking that of unexposed potato. When presented individually, TMTT was attractive to ladybirds whereas (E)-nerolidol was repellent. Volatile exchange between unattacked plants and consequent increased attractiveness for ladybirds may be a mechanism that contributes to the increased abundance of natural enemies in complex plant habitats.