Search results for "Geraniol"
showing 10 items of 22 documents
Essential Oil Yield, Chemical Composition, and Total Citral Content of Nine Cultivars of Cymbopogon Species from Western India
2016
ABSTRACTThe essential oil composition of five elite Cymbopogon varieties (OD-19, Pragati, RRL-16, NLG-84) and a hybrid (CPK-25) and four new selections (LS-1 to LS-4) were determined by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The oil yield ranged from 0.31% to 1.0% with CPK-25 (1.0%) and LS-2 (0.95%) containing the highest. A total of 66 compounds, constituting 84.6–94.3% of the oils, were identified. The main compounds were geranial (29.9–41.6%), neral (25.8–32.5%), citronellol (0.3–12.8%), geranyl acetate (1.2–8.4%), and geraniol (1.8–8.2%). Of the cultivars, OD-19 (74.1%) had the highest and LS-3 (55.7%) contained the lowest amount of total citral. CKP-2…
Chemical Composition and antimicrobial activity of the essential oils from two species of Thimus growing wild in southern Italy
2009
The volatile constituents of the aerial parts of two samples of Thymus longicaulis C. Presl, collected in Campania and in Sicily, and two samples of Thymus pulegioides L. from the same regions, were extracted by hydrodistillation and analyzed. Considering the four oils together, seventy-eight different compounds were identified: 57 for Thymus longicaulis from Sicily (91.1% of the total oil), 40 for Thymus longicaulis from Campania (91.5% of the oil), 39 for Thymus pulegioides from Sicily (92.5% of the oil) and 29 for Thymus pulegioides from Campania (90.1% of the oil). The composition of the oils is different, although the most abundant components are identical in T. pulegioides. The essent…
Construction of a genetically modified wine yeast strain expressing the Aspergillus aculeatus rhaA gene, encoding an -L-Rhamnosidase of enological in…
2003
Monoterpenes such as geraniol, linalool, and -terpineol present in grapes determine the varietal flavor properties of young quality wines made from Muscat varieties (for reviews, see references 19 and 21). Geraniol and linalool are considered to be the most important of the monoterpene alcohols, as they are present in greater concentrations and have lower flavor thresholds than other major wine monoterpenes. In particular, linalool is thought to be responsible for the grapelike aroma of wines produced from the Muscat variety. A large proportion of
Geranylgeraniol - a new potential therapeutic approach to bisphosphonate associated osteonecrosis of the jaw.
2010
Bisphosphonate associated osteonecrosis of the jaw (BP-ONJ) is one of the main side effects of bisphosphonate therapy (BPT). To date, there is no effective therapy of the BP-ONJ. Nitrogen-containing bisphosphonates (N-BPs) are particularly able to inhibit pyrophosphate synthase (FPPS) in the mevalonate pathway (MVP). Consequent of decreased synthesis of the metabolite Geranylgeraniol (GGOH) is believed to largely account for the development of BP-ONJ. Negative effect of N-BPs could be shown, resulting in decreased viability and migration capacity of different cell types of hard and soft tissues such as osteoblasts, fibroblast und endothelial cells. Aim of our in vitro study was to demonstra…
Combination of phenolic acids and essential oils against Listeria monocytogenes
2015
Abstract Listeria monocytogenes is a psychrotrophic pathogen widely distributed in meat processing plants. Listeriosis presents very low morbidity, but very high mortality rates. Several outbreaks involving this bacterium have been reported due to the consumption of refrigerated meat and dairy products. The objective of the present study was to evaluate the in vitro antimicrobial activity of 10 phenolic acids (PAs) and 4 essential oil compounds (EOCs) as natural alternatives to control L. monocytogenes growth. The minimum inhibitory concentration (MIC) of all natural compounds was determined at pH 5, 6 and 7. The 4 most potent PAs (ρ-hydroxybenzoic acid, ferulic acid, o-coumaric acid and sy…
Modulation of geraniol metabolism during alcohol fermentation
2004
J. Inst. Brew. 110(3), 213–219, 2004 Geraniol is the main monoterpenol present in Gewurtztraminer white grapes and in some red aromatic grapes from northern Italy. During fermentation, the geraniol concentration showed a dramatic drop and a small amount was transformed into linalool and -terpineol by an acid catalysed chemical reaction. Yeast are responsible for changing most of the geraniol to citronellol through enzymatic reactions. The final aroma of wine is due mainly to both the untransformed geraniol and the formed citronellol. In this study, competition between the geraniol-citronellol transformation and another metabolic process, in which according to our hypothesis sterol biosynthe…
Evaluation of Chemical Composition of Essential Oils Derived from Different Pelargonium Species Leaves
2019
Abstract Plants have been used for their aromatic and medicinal purposes for centuries. The genus Pelargonium contains about 250-280 species and cultivated around the world for the production of essential oils and absolutes. Pelargonium species are remarkable for their odour diversity, from fresh, lemon and minty scent, through floral, rose, fruity up to spicy and camphoreous smell as well as many health beneficial properties, that is why their essential oils are widely used in perfume, cosmetic, food and pharmaceutical industries. The aim of this study was to determine variability in populations of Pelargonium genus by evaluating their differences in quantitative and qualitative essential …
Behaviour-modifying compounds for management of the red palm weevil (Rhynchophorus ferrugineusOliver)
2015
BACKGROUND Populations of red palm weevil (RPW), a severe pest of palms in Mediterranean countries, might be limited by semiochemical-based behaviour-disrupting methods. We evaluated the effects of electroantennogram (EAG)-active plant volatiles on the behaviour of RPWs from Italy and Israel. In field experiments, α-pinene, citronellol, geraniol, citral and 1-octen-3-ol were tested for their ability to disrupt attraction to pheromone–kairomone and molasses baited traps. Those that were found to be disruptive in the field were evaluated in a laboratory choice bioassay in individual cages for their effect on RPW female feeding and oviposition. RESULTS Field experiments showed reduced captures…
Fractionation of glycoside aroma precursors in neutral grapes. Hydrolysis and conversion by Saccharomyces cerevisiae
2004
Abstract Glycoconjugated aroma precursors from neutral grape varieties were fractionated on 5 g C18 RP cartridge. Each of the seven fractions collected was divided in three parts: first part was hydrolysed with Pectinol in order to determine total aromatic heterosides, while the second part was treated with an active strain of the yeast Saccharomyces cerevisiae UCLM 325 and the third part with acetonic powder of the same yeast strain. The studied strain proved effective in the hydrolysis of the heterosides of nerol and geraniol, cis-8-hydroxy-linalool, 8-hydroxy-dihydro-linalool, some benzenoids and some norisoprenoids derivatives such as vomifoliol and 3-oxo-α-ionol. Only whole cells are a…
De novo production of six key grape aroma monoterpenes by a geraniol synthase-engineered S. cerevisiae wine strain
2015
[Background] Monoterpenes are important contributors to grape and wine aroma. Moreover, certain monoterpenes have been shown to display health benefits with antimicrobial, anti-inflammatory, anticancer or hypotensive properties amongst others. The aim of this study was to construct self-aromatizing wine yeasts to overproduce de novo these plant metabolites in wines.