SciCombinator

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Concept: Lavender

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Lavender essential oils are predominantly constituted of regular monoterpenes, for example linalool, 1, 8 cineole and camphor. However, they also contain irregular monoterpenes including lavandulol and lavandulyl acetate. Although the majority of genes responsible for the production of regular monoterpenes in lavenders are now known, enzymes (including LPPS) catalyzing the biosynthesis of irregular monoterpenes in these plants have not been described. Here, we report the isolation and functional characterization of a novel cis prenyl diphosphate synthase cDNA, termed L. x intermedia lavandulyl diphosphate synthase (LiLPPS), through a homology based cloning strategy. The LiLPPS ORF, encoding for a 305 amino acids long protein, was expressed in E. coli and the recombinant protein was purified by NiNTA affinity chromatography. The ca. 34.5 kDa bacterially produced protein specifically catalyzed the head to middle condensation of two DMAPP units to LPP in vitro with apparent Km and kcat values of 208 microM and 0.1, respectively. LiLPPS is a homodimeric enzyme with a sigmoidal saturation curve and hill coefficient of 2.7, suggesting a positive cooperative interaction among its catalytic sites. LiLPPS could be used to modulate the production of lavandulol and its derivatives in plants through metabolic engineering.

Concepts: DNA, Protein, Amino acid, Metabolism, Enzyme, Escherichia coli, Essential oil, Lavender

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Lavandula species are some of the most popular ornamental and medicinal plants with great economic values. These species are vegetative propagated by stem cuttings. However, the poor rooting ability and vulnerability of plantlets to contamination are major limiting factors for propagation. In vitro culture methods are suitable to overcome these limitations. This chapter describes protocols for in vitro propagation of Lavandula viridis L'Hér and Lavandula vera DC. Nodal shoot proliferation of L. viridis and plant regeneration from leaf-derived callus of L. vera by an “open culture system” are highlighted.

Concepts: Plant, Culture, Lavender, Lavandula angustifolia, Perennial plant, Plant propagation, Popular culture, Lavandula

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Ethnopharmacological relevance: This study aimed to document traditional uses of medicinal plants in the Marmaris district of south-west Anatolia and to compare this information with our current knowledge of plant medicine in Turkey and the Mediterranean countries. Materials and methods: We collected the information through semi-structured interviews with 98 informants (51 men, 47 women). In addition, the relative importance value of species was determined and informant consensus factor (FIC) was calculated for the medicinal plants included in the study. RESULTS: We report the medicinal uses of 64 plant species belonging to 35 families, including the uses of 9 essential oils. Most of the medicinal plants used in the Marmaris district belong to the families Lamiaceae (13 species) and Asteraceae (4 species). The most commonly used plant species are Salvia fruticosa, Origanum onites, Lavandula stoechas, Mentha pulegium and Satureja thymbra. For the purposes of making essential oils, Salvia fruticosa is the plant species most commonly used. Two of the plants we report on (Liquidambar orientalis, Phlomis lycia) are endemic to Turkey and the East Agean Islands. Sideritis libanotica subsp. linearis is endemic to Turkey, Lebanon and Syria. Thymus cilicicus is endemic to Turkey, East Agean Islands, Lebanon and Syria. For six plant species (Narcissus tazetta, Lagenaria siceraria, Hypericum montbrettii, Phlomis grandiflora var. grandiflora, Polygonum bellardii, Crataegus aronia var. aronia) we report new different ethnobotanical uses not previously reported in Turkey. CONCLUSIONS: Some plants are used for medicinal purposes both in Marmaris and in other parts of Turkey and in the Mediterranean countries, either for the same or for different purposes. This paper helps preserve valuable information that may otherwise be lost to future generations.

Concepts: Species, Mediterranean Sea, Shrub, Lamiaceae, Medicinal plants, Essential oil, Anatolia, Lavender

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Artemisia gilvescens, a traditional Chinese medicinal plant, is chiefly distributed in the middle and lower reaches of the Yangtze River, China. Chemical composition of hydrodistilled essential oil from A. gilvescens was investigated by gas chromatography and mass spectroscopy (GC-MS), and larvicidal activity of the oil and its six main compounds against Anopheles anthropophagus was carried out by WHO method. In total, 56 compounds corresponding to 98.20 % of the total oil were identified and the major compounds identified were camphor (13.49 %), eucalyptol (12.13 %), terpine-4-ol (9.65 %), germacrene D (8.62 %), caryophyllene oxide (4.65 %), and caryophyllene (4.29 %). Essential oil induced 8, 46, 80, 85, 94, and 100 % larval mortality at the concentrations of 25, 50, 75, 100, 125, and 150 mg/l, and the LC(50) and LC(90) values were 49.95 and 97.36 mg/l, respectively. Among the six compounds, the most potent larvicidal compound was caryophyllene oxide and germacrene D, with LC(50) values of 49.46 and 49.81 mg/l and LC(90) values of 115.38 and 106.19 mg/l, respectively. Terpine-4-ol had LC(50) and LC(90) values of 76.70 and 139.42 mg/l followed by camphor which showed LC(50) and LC(90) values of 129.17 and 192.42 mg/l, respectively. The least potent among the six compounds were eucalyptol and caryophyllene, with and LC(50) value exceeding 200 mg/l. In general, it also shows a dose-dependent effect on mortality, with increasing concentrations of essential oil and compounds increasing mortality of the larvae. The essential oil of A. gilvescens and its several major compounds may have potential for use in control of A. anthropophagus.

Concepts: China, Chromatography, Yangtze River, Chemical compound, The Essential, Essential oil, Camphor, Lavender

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Recently, an essential oil of selected quality produced from the flowering tops of Lavandula angustifolia Mill. by steam distillation (Silexan) has been approved in Germany for the treatment of restlessness in case of anxious mood. Based on the observed clinical effects, it has been speculated that lavender oil may exert benzodiazepine-like action including the known dependence and abuse potential of this class of drugs. Although no evidence for such an activity was generated during the long-standing medicinal use of lavender oil, further preclinical investigations were now conducted to evaluate this potential side effect in more detail. Twelve adult, male, Sprague-Dawley rats were trained to discriminate the benzodiazepine drug diazepam (2mg/kg i.p.) from saline using a two-lever operant procedure. After approximately 40 training sessions the majority of rats learned the discrimination and pre-treatment with ascending doses of diazepam (0.3-2mg/kg i.p.) produced a dose related generalization to the diazepam cue. In these same animals Silexan was administered to see if animals recognized the drug as “diazepam-like” i.e. generalized to diazepam or “saline-like”. Silexan tested at doses 3-30mg/kg i.p. produced almost exclusively (>90%) saline-like responding. Also there was no effect of Silexan on response rate, i.e. rate of lever pressing, at any dose suggesting that the test article is well tolerated and does not exert a sedating effect. In sum, Silexan has no diazepam-like interoceptive property in adult, male rats. This suggests that Silexan does not share the potential of benzodiazepines to induce the development of tolerance, dependence and addiction.

Concepts: Pharmacology, Drug addiction, Addiction, Diazepam, Benzodiazepine, Essential oil, Lavender, Lavandula angustifolia

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BACE-1 is an aspartic protease involved in the conversion of amyloid precursor protein (APP) to amyloid-β (Aβ) in vivo, which is one of the key steps in the development and progression of Alzheimer’s disease. In a previous screening procedure for inhibitors of BACE-1 activity, the oil of Lavandula luisieri was identified as the most potent among several essential oils. The inhibitory effect of this essential oil on Aβ production was also demonstrated in a cellular assay. The composition of the volatile oil and the isolation of the compound responsible for the inhibitory activity were also reported. The present work focused on the characterization of the inhibition of BACE-1 by this active compound, a monoterpene necrodane ketone, 2,3,4,4-tetramethyl-5-methylenecyclopent-2-enone (1), with assessment of its Ki value and the type of inhibition. The dose-related effects of the compound were also evaluated using two different cell lines, with determinations of the respective EC50 values. The entire oil and the 2,3,4,4-tetramethyl-5-methylenecyclopent-2-enone (1) were tested on a triple transgenic mouse model of Alzheimer’s disease. The overall results showed that compound 1 displayed a dose-dependent inhibition of BACE-1 in cellular and mouse models of Alzheimer’s disease and is therefore capable of passing through cellular membranes and the blood-brain barrier.

Concepts: Alzheimer's disease, Amyloid precursor protein, Essential oil, Oil, Oils, Lavender, Presenilin, Aromatherapy

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Sub-individual variation in traits of homologous structures has multiple ecological consequences for individuals and populations. Assessing the evolutionary significance of such effects requires an improved knowledge of the mechanisms underlying within-plant phenotypic heterogeneity. The hypothesis that continuous within-plant variation in some phenotypic traits can be associated with epigenetic mosaicism was examined.

Concepts: DNA, Genetics, Natural selection, Evolution, Biology, Phenotype, Lavender, Homology

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The aim of study was to compare the content of phenolic acids and flavonoids in two cultivars of Lavandula angustifolia: ‘Blue River’ and ‘Ellagance Purple’, including flowers and leafy stalks. Total phenolics and total flavonoids contents were determined by UV-Vis spectroscopy. The contents of total phenolics in leafy stalks (3.71-4.06 mg g(-1) d.m.) were higher than in flowers (1.13-1.14 mg g(-1) d.m.). Similarly, higher total contents of flavonoids were determined in leafy stalks (3.41-3.51 mg g(-1) d.m.), as compared with flowers (0.86-0.91 mg g(-1) d.m.). Phenolic acids and flavonoids were identified and quantified using HPLC and UPLC methods. Three phenolic acids were determined: rosmarinic, ferulic and caffeic acid. Lavender extracts contained also flavonoids from group of apigenin, luteolin and quercetin. Higher amounts of luteolin diglucuronide and luteolin glucuronide were found in leafy stalks in comparison to flowers. Obtained results indicate that leafy stalks of lavender can be also valuable source of antioxidant compounds.

Concepts: Spectroscopy, Caffeic acid, Phenols, Lavender, Lavandula angustifolia, Lavandula

22

Lavandula stoechas subsp. stoechas and Mentha spicata subsp. spicata are used for the treatment of sinusitis in Turkish folk medicine. The components of essential oils obtained by hydrodistillation were determined by gas chromatography-flame ionization detector (GC-FID), gas chromatography/mass spectrometry (GC/MS), and thin layer chromatography (TLC). Major components of L. stoechas and M. spicata oils were determined as camphor (46.7%) and carvone (60.6%), respectively. The antibacterial activity of essential oils and their main components were tested against the common selected sinusitis pathogens Streptococcus pneumoniae, Streptococcus pyogenes, Staphylococcus aureus, Haemophilus influenzae, Moraxella catarrhalis, and Pseudomonas aeruginosa using in vitro agar diffusion, microdilution, and vapor diffusion methods. As a result, the tested plant materials, which are locally and natively used against sinusitis, were relatively mild antibacterial (in vitro MICs 310-1250 μg/mL) in action. To use essential oils and their components safely in sinusitis therapy, further detailed in vivo experiments are needed to support their efficacy.

Concepts: Bacteria, Pneumonia, Streptococcus pneumoniae, Chromatography, Haemophilus influenzae, Essential oil, Thin layer chromatography, Lavender

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BACKGROUND: A majority of reproductive-age women experience a constellation of various symptoms in the premenstrual phase, commonly known as premenstrual syndrome (PMS). Despite its prevalence, however, no single treatment is universally recognized as effective, and many women turn to alternative approaches, including aromatherapy, a holistic mind and body treatment. The present study investigated the soothing effects of aromatherapy on premenstrual symptoms using lavender (Lavandula angustifolia), a relaxing essential oil, from the perspective of autonomic nervous system function. METHODS: Seventeen women (20.6 +/- 0.2 years) with mild to moderate subjective premenstrual symptoms participated in a randomized crossover study. Subjects were examined on two separate occasions (aroma and control trials) in the late-luteal phases. Two kinds of aromatic stimulation (lavender and water as a control) were used. This experiment measured heart rate variability (HRV) reflecting autonomic nerve activity and the Profile of Mood States (POMS) as a psychological index before and after the aromatic stimulation. RESULTS: Only a 10-min inhalation of the lavender scent significantly increased the high frequency (HF) power reflecting parasympathetic nervous system activity in comparison with water (aroma effect: F = 4.50, p = 0.050; time effect: F = 5.59, p = 0.017; aroma x time effect: F = 3.17, p = 0.047). The rate of increase in HF power was greater at 10–15 min (p = 0.051) and 20–25 min (p = 0.023) in the lavender trial than in the control trial with water. In addition, POMS tests revealed that inhalation of the aromatic lavender oil significantly decreased two POMS subscales—depression–dejection (p = 0.045) and confusion (p = 0.049)—common premenstrual symptoms, in the late-luteal phase, as long as 35 min after the aroma stimulation. CONCLUSIONS: The present study indicated that lavender aromatherapy as a potential therapeutic modality could alleviate premenstrual emotional symptoms, which, at least in part, is attributable to the improvement of parasympathetic nervous system activity. This study further implies that HRV could evaluate the efficacy of aromatherapy using various fragrances to relieve premenstrual symptoms, and ultimately, support the mind and body health of women.

Concepts: Nervous system, Brain, Crossover study, Autonomic nervous system, Parasympathetic nervous system, Essential oil, Lavender, Aromatherapy