Biotechnological production of limonene in microorganisms

OpenAIRE

Jongedijk, Esmer; Cankar, Katarina; Buchhaupt, Markus; Schrader, Jens; Bouwmeester, Harro; Beekwilder, Jules

2016-01-01

This mini review describes novel, biotechnology-based, ways of producing the monoterpene limonene. Limonene is applied in relatively highly priced products, such as fragrances, and also has applications with lower value but large production volume, such as biomaterials. Limonene is currently produced as a side product from the citrus juice industry, but the availability and quality are fluctuating and may be insufficient for novel bulk applications. Therefore, complementary microbial producti...

Positive patch test reactions to oxidized limonene: exposure and relevance.

Science.gov (United States)

Bråred Christensson, Johanna; Andersen, Klaus E; Bruze, Magnus; Johansen, Jeanne D; Garcia-Bravo, Begoña; Gimenez Arnau, Ana; Goh, Chee-Leok; Nixon, Rosemary; White, Ian R

2014-11-01

R-Limonene is a common fragrance terpene found in domestic and industrial products. R-Limonene autoxidizes on air exposure, and the oxidation products can cause contact allergy. In a recent multicentre study, 5.2% (range 2.3-12.1%) of 2900 patients showed a positive patch test reaction to oxidized R-limonene. To study the exposure to limonene among consecutive dermatitis patients reacting to oxidized R-limonene in an international setting, and to assess the relevance of the exposure for the patients' dermatitis. Oxidized R-limonene 3.0% (containing limonene hydroperoxides at 0.33%) in petrolatum was tested in 2900 consecutive dermatitis patients in Australia, Denmark, the United Kingdom, Singapore, Spain, and Sweden. A questionnaire assessing exposure to limonene-containing products was completed. Overall, exposure to products containing limonene was found and assessed as being probably relevant for the patients' dermatitis in 36% of the limonene-allergic patients. In Barcelona and Copenhagen, > 70% of the patients were judged to have had an exposure to limonene assessed as relevant. Oxidized R-limonene is a common fragrance allergen, and limonene was frequently found in the labelling on the patients' products, and assessed as relevant for the patients' dermatitis. A large number of domestic and occupational sources for contact with R-limonene were identified. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Tribological properties of limonene bisphosphonates

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Limonene was chemically modified by reacting it with dialkyl phosphites of varying alkyl structures under inert atmosphere in the presence of free radical initiators. The reaction gave a mixture of mono- and di-adduct products, and was optimized to produce only the diadduct product limonene bisphosp...

Effects of Foeniculum vulgare essential oil compounds, fenchone and limonene, on experimental wound healing.

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Keskin, I; Gunal, Y; Ayla, S; Kolbasi, B; Sakul, A; Kilic, U; Gok, O; Koroglu, K; Ozbek, H

2017-01-01

We investigated the wound healing efficacy of the Foeniculum vulgare compounds, fenchone and limonene, using an excisional cutaneous wound model in rats. An excision wound was made on the back of the rat and fenchone and limonene were applied topically to the wounds once daily, separately or together, for 10 days. Tissue sections from the wounds were evaluated for histopathology. The healing potential was assessed by comparison to an untreated control group and an olive oil treated sham group. We scored wound healing based on epidermal regeneration, granulation tissue thickness and angiogenesis. After day 6, wound contraction with limonene was significantly better than for the control group. Ten days after treatment, a significant increase was observed in wound contraction and re-epithelialization in both fenchone and limonene oil treated groups compared to the sham group. Groups treated with fenchone and with fenchone + limonene scored significantly higher than the control group, but the difference was not statistically significant compared to the olive oil treated group. Our findings support the beneficial effects of fenchone and limonene for augmenting wound healing. The anti-inflammatory and antimicrobial activities of fenchone and limonene oil increased collagen synthesis and decreased the number of inflammatory cells during wound healing and may be useful for treating skin wounds.

Metabolic engineering of oleaginous yeast Yarrowia lipolytica for limonene overproduction.

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Cao, Xuan; Lv, Yu-Bei; Chen, Jun; Imanaka, Tadayuki; Wei, Liu-Jing; Hua, Qiang

2016-01-01

Limonene, a monocyclic monoterpene, is known for its using as an important precursor of many flavoring, pharmaceutical, and biodiesel products. Currently, d-limonene has been produced via fractionation from essential oils or as a byproduct of orange juice production, however, considering the increasing need for limonene and a certain amount of pesticides may exist in the limonene obtained from the citrus industry, some other methods should be explored to produce limonene. To construct the limonene synthetic pathway in Yarrowia lipolytica , two genes encoding neryl diphosphate synthase 1 (NDPS1) and limonene synthase (LS) were codon-optimized and heterologously expressed in Y. lipolytica . Furthermore, to maximize limonene production, several genes involved in the MVA pathway were overexpressed, either in different copies of the same gene or in combination. Finally with the optimized pyruvic acid and dodecane concentration in flask culture, a maximum limonene titer and content of 23.56 mg/L and 1.36 mg/g DCW were achieved in the final engineered strain Po1f-LN-051, showing approximately 226-fold increase compared with the initial yield 0.006 mg/g DCW. This is the first report on limonene biosynthesis in oleaginous yeast Y. lipolytica by heterologous expression of codon-optimized tLS and tNDPS1 genes. To our knowledge, the limonene production 23.56 mg/L, is the highest limonene production level reported in yeast. In short, we demonstrate that Y. lipolytica provides a compelling platform for the overproduction of limonene derivatives, and even other monoterpenes.

Limonene inhibits Candida albicans growth by inducing apoptosis.

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Thakre, Archana; Zore, Gajanan; Kodgire, Santosh; Kazi, Rubina; Mulange, Shradha; Patil, Rajendra; Shelar, Amruta; Santhakumari, Bayitigeri; Kulkarni, Mahesh; Kharat, Kiran; Karuppayil, Sankunny Mohan

2018-07-01

Anti-Candida potential of limonene was evaluated against planktonic growth, biofilm (adhesion, development and maturation) and morphogenesis of Candida albicans in this study. Limonene is a major constituent of citrus oil and most frequently used terpene in food and beverage industry due to its pleasant fragrance, nontoxic, and is generally recognized as safe (GRAS) flavoring agent as well as treatment option in many gastrointestinal diseases.Limonene exhibited excellent anti-Candida activity and was equally effective against planktonic growth of C. albicans isolates differentially susceptible to FLC (N = 35). Limonene inhibited morphogenesis significantly at low concentration. However, it showed stage dependent activity against biofilm formation, that is, it was more effective against adhesion followed by development and maturation. Limonene also exhibited excellent synergy with FLC against planktonic and biofilm growth. SWATH-MS analysis led to identification of limonene responsive proteins that provided molecular insight of its anti-Candida activity. Proteomic analysis revealed upregulation of proteins involved in cell wall glucan synthesis (Kre6); oxidative stress (Rhr2, Adh7 and Ebp1); DNA damage stress (Mbf1 and Npl3); nucleolar stress (Rpl11, Rpl7, Rpl29, Rpl15) and down regulation of cytoskeleton organization (Crn1, Pin3, Cct8, Rbl2), and so forth, in response to limonene. Limonene mediated down regulation of Tps3 indicates activation of caspase (CaMca1) and induction of apoptosis in C. albicans. These results suggest that limonene inhibits C. albicans growth by cell wall/membrane damage induced oxidative stress that leads to DNA damage resulting into modulation of cell cycle and induction of apoptosis through nucleolar stress and metacaspase dependent pathway.

Acute Limonene Toxicity in Escherichia coli Is Caused by Limonene Hydroperoxide and Alleviated by a Point Mutation in Alkyl Hydroperoxidase AhpC

OpenAIRE

Chubukov, Victor; Mingardon, Florence; Schackwitz, Wendy; Baidoo, Edward E. K.; Alonso-Gutierrez, Jorge; Hu, Qijun; Lee, Taek Soon; Keasling, Jay D.; Mukhopadhyay, Aindrila

2015-01-01

Limonene, a major component of citrus peel oil, has a number of applications related to microbiology. The antimicrobial properties of limonene make it a popular disinfectant and food preservative, while its potential as a biofuel component has made it the target of renewable production efforts through microbial metabolic engineering. For both applications, an understanding of microbial sensitivity or tolerance to limonene is crucial, but the mechanism of limonene toxicity remains enigmatic. I...

Rhodococcus erythropolis DCL14 Contains a Novel Degradation Pathway for Limonene

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van der Werf, Mariët J.; Swarts, Henk J.; de Bont, Jan A. M.

1999-01-01

Strain DCL14, which is able to grow on limonene as a sole source of carbon and energy, was isolated from a freshwater sediment sample. This organism was identified as a strain of Rhodococcus erythropolis by chemotaxonomic and genetic studies. R. erythropolis DCL14 also assimilated the terpenes limonene-1,2-epoxide, limonene-1,2-diol, carveol, carvone, and (−)-menthol, while perillyl alcohol was not utilized as a carbon and energy source. Induction tests with cells grown on limonene revealed that the oxygen consumption rates with limonene-1,2-epoxide, limonene-1,2-diol, 1-hydroxy-2-oxolimonene, and carveol were high. Limonene-induced cells of R. erythropolis DCL14 contained the following four novel enzymatic activities involved in the limonene degradation pathway of this microorganism: a flavin adenine dinucleotide- and NADH-dependent limonene 1,2-monooxygenase activity, a cofactor-independent limonene-1,2-epoxide hydrolase activity, a dichlorophenolindophenol-dependent limonene-1,2-diol dehydrogenase activity, and an NADPH-dependent 1-hydroxy-2-oxolimonene 1,2-monooxygenase activity. Product accumulation studies showed that (1S,2S,4R)-limonene-1,2-diol, (1S,4R)-1-hydroxy-2-oxolimonene, and (3R)-3-isopropenyl-6-oxoheptanoate were intermediates in the (4R)-limonene degradation pathway. The opposite enantiomers [(1R,2R,4S)-limonene-1,2-diol, (1R,4S)-1-hydroxy-2-oxolimonene, and (3S)-3-isopropenyl-6-oxoheptanoate] were found in the (4S)-limonene degradation pathway, while accumulation of (1R,2S,4S)-limonene-1,2-diol from (4S)-limonene was also observed. These results show that R. erythropolis DCL14 metabolizes both enantiomers of limonene via a novel degradation pathway that starts with epoxidation at the 1,2 double bond forming limonene-1,2-epoxide. This epoxide is subsequently converted to limonene-1,2-diol, 1-hydroxy-2-oxolimonene, and 7-hydroxy-4-isopropenyl-7-methyl-2-oxo-oxepanone. This lactone spontaneously rearranges to form 3-isopropenyl-6-oxoheptanoate. In

Capturing of the monoterpene olefin limonene produced in Saccharomyces cerevisiae.

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Jongedijk, Esmer; Cankar, Katarina; Ranzijn, Jorn; van der Krol, Sander; Bouwmeester, Harro; Beekwilder, Jules

2015-01-01

Monoterpene olefins such as limonene are plant compounds with applications as flavouring and fragrance agents, as solvents and potentially also in polymer and fuel chemistry. We engineered baker's yeast Saccharomyces cerevisiae to express a (-)-limonene synthase from Perilla frutescens and a (+)-limonene synthase from Citrus limon. Both proteins were expressed either with their native plastid targeting signal or in a truncated form in which the plastidial sorting signal was removed. The yeast host strain for expression was AE9 K197G, which expresses a mutant Erg20 enzyme. This enzyme catalyses the formation of geranyl diphosphate, which is the precursor for monoterpenes. Several methods were tested to capture limonene produced by the yeast. Extraction from the culture medium by pentane, or by the addition of CaCl2 followed by solid-phase micro-extraction, did not lead to detectable limonene, indicating that limonene is rapidly lost from the culture medium. Volatile terpenes such as limonene may also be trapped in a dodecane phase added to the medium during fermentation. This method resulted in recovery of 0.028 mg/l (+)-limonene and 0.060 mg/l (-)-limonene in strains using the truncated Citrus and Perilla synthases, respectively. Trapping the headspace during culture of the limonene synthase-expressing strains resulted in higher titres, at 0.12 mg/l (+)-limonene and 0.49 mg/l (-)-limonene. These results show that the volatile properties of the olefins produced require specific methods for efficient recovery of these molecules from biotechnological production systems. Copyright © 2014 John Wiley & Sons, Ltd.

Xanthobacter sp. C20 contains a novel bioconversion pathway for limonene

OpenAIRE

Werf, M.J. van der; Keijzer, P.M.; Schaft, P.H. van der

2000-01-01

Xanthobacter sp. C20 was isolated from sediment of the river Rhine using cyclohexane as sole source of carbon and energy. Xanthobacter sp. C20 converted both enantiomers of limonene quantitatively into limonene-8,9-epoxide, a not previously described bioconversion product of limonene. With (4R)-limonene, (4R,8R)-limonene-8,9-epoxide was formed as the only reaction product, while (4S)-limonene was converted into a (78:22) mixture of (4S,8R)- and (4S,8S)-limonene-8,9-epoxide. Cytochrome P-450 w...

Metabolic engineering of oleaginous yeast Yarrowia lipolytica for limonene overproduction

OpenAIRE

Cao, Xuan; Lv, Yu-Bei; Chen, Jun; Imanaka, Tadayuki; Wei, Liu-Jing; Hua, Qiang

2016-01-01

Background Limonene, a monocyclic monoterpene, is known for its using as an important precursor of many flavoring, pharmaceutical, and biodiesel products. Currently, d-limonene has been produced via fractionation from essential oils or as a byproduct of orange juice production, however, considering the increasing need for limonene and a certain amount of pesticides may exist in the limonene obtained from the citrus industry, some other methods should be explored to produce limonene. Results T...

d-Limonene: a bioactive food component from citrus and evidence for a potential role in breast cancer prevention and treatment

Directory of Open Access Journals (Sweden)

Jessica A. Miller

2011-10-01

Full Text Available Although limited, observations from cell culture, animal, and epidemiological studies support the presence of anti-cancer properties in citrus peel and the primary bioactive food constituent, d-limonene. Early evidence from animal models suggests that when ingested, d-limonene exhibits a wide spectrum of biologic activity including chemotherapeutic and chemopreventive effects. In some of these early models, an analog of d-limonene, perillyl alcohol, demonstrated a more potent effect than d-limonene itself. Yet, when perillyl alcohol advanced to clinical trials, several trials were ended early due to doselimiting toxicities. Alternatively, oral d-limonene administration in humans is well tolerated even at high doses supporting its investigation as a potential bioactive for cancer prevention. Though the exact mechanisms of action of d-limonene are unclear, immune modulation and antiproliferative effects are commonly reported. Here, we review the pre-clinical evidence for d-limonene’s anticancer mechanisms, bioavailability, and safety, as well as the evidence for anti-cancer effects in humans, focusing on studies relevant to its use in the prevention and treatment of breast cancer.

NIOSH Health Hazard Evaluation for d-Limonene

Science.gov (United States)

1993-11-01

of natural hydrocarbons referred to as terpenes (d-limonene is a monoterpene ). The other form of limonene is called 1-limonene, and a mixture of the...as a flavor and fragrance additive in perfumes, soaps, foods, chewing gum and beverages, and is the most widely distribiit. monoterpene ." 4’ The use of...effect and skin irritation of monocyclic monoterpenes . Drug Des Deliv 6:229-238. 29. Hooser SB, Beasley VR, Everitt J1 [1986]. Effects of an

Temperature dependence on mutual solubility of binary (methanol + limonene) mixture and (liquid + liquid) equilibria of ternary (methanol + ethanol + limonene) mixture

International Nuclear Information System (INIS)

Tamura, Kazuhiro; Li Xiaoli; Li Hengde

2009-01-01

Mutual solubility data of the binary (methanol + limonene) mixture at the temperatures ranging from 288.15 K close to upper critical solution temperature, and ternary (liquid + liquid) equilibrium (tie-lines) of the (methanol + ethanol + limonene) mixture at the temperatures (288.15, 298.15, and 308.15) K have been obtained. The experimental results have been represented accurately in terms of the extended and modified UNIQUAC models with binary parameters, compared with the UNIQUAC model. The temperature dependence of binary and ternary (liquid + liquid) equilibrium for the binary (methanol + limonene) and ternary (methanol + ethanol + limonene) mixtures could be calculated successfully using the extended and modified UNIQUAC model

Heterogeneous Reactions of Limonene on Mineral Dust: Impacts of Adsorbed Water and Nitric Acid.

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Lederer, Madeline R; Staniec, Allison R; Coates Fuentes, Zoe L; Van Ry, Daryl A; Hinrichs, Ryan Z

2016-12-08

Biogenic volatile organic compounds (BVOCs), including the monoterpene limonene, are a major source of secondary organic aerosol (SOA). While gas-phase oxidation initiates the dominant pathway for BVOC conversion to SOA, recent studies have demonstrated that biogenic hydrocarbons can also directly react with acidic droplets. To investigate whether mineral dust may facilitate similar reactive uptake of biogenic hydrocarbons, we studied the heterogeneous reaction of limonene with mineral substrates using condensed-phase infrared spectroscopy and identified the formation of irreversibly adsorbed organic products. For kaolinite, Arizona Test Dust, and silica at 30% relative humidity, GC-MS identified limonene-1,2-diol as the dominant product with total organic surface concentrations on the order of (3-5) × 10 18 molecules m -2 . Experiments with 18 O-labeled water support a mechanism initiated by oxidation of limonene by surface redox sites forming limonene oxide followed by water addition to the epoxide to form limonenediol. Limonene uptake on α-alumina, γ-alumina, and montmorillonite formed additional products in high yield, including carveol, carvone, limonene oxide, and α-terpineol. To model tropospheric processing of mineral aerosol, we also exposed each mineral substrate to gaseous nitric acid prior to limonene uptake and identified similar surface adsorbed products that were formed at rates 2 to 5 times faster than without nitrate coatings. The initial rate of reaction was linearly dependent on gaseous limonene concentration between 5 × 10 12 and 5 × 10 14 molecules cm -3 (0.22-20.5 ppm) consistent with an Eley-Rideal-type mechanism in which gaseous limonene reacts directly with reactive surface sites. Increasing relative humidity decreased the amount of surface adsorbed products indicating competitive adsorption of surface adsorbed water. Using a laminar flow tube reactor we measured the uptake coefficient for limonene on kaolinite at 25% RH to range from

Biobased lubricant additives derived from limonene

Science.gov (United States)

Limonene is a natural product widely found in many plants as a constituent of “essential oils.” It is commercially produced as a byproduct of the citrus industry from processing of fruits such as oranges, lemons, lime, tangerines, mandarins, and grapefruits. Limonene is a C10 hydrocarbon with a com...

Response of Saccharomyces cerevisiae to D-limonene-induced oxidative stress.

Science.gov (United States)

Liu, Jidong; Zhu, Yibo; Du, Guocheng; Zhou, Jingwen; Chen, Jian

2013-07-01

In the present study, we investigated the mode of cell response induced by D-limonene in Saccharomyces cerevisiae. D-limonene treatment was found to be accompanied by intracellular accumulation of reactive oxygen species (ROS). Since ROS impair cell membranes, an engineered strain with enhanced membrane biosynthesis exhibited a higher tolerance to D-limonene. Subsequent addition of an ROS scavenger significantly reduced the ROS level and alleviated cell growth inhibition. Thus, D-limonene-induced ROS accumulation plays an important role in cell death in S. cerevisiae. In D-limonene-treated S. cerevisiae strains, higher levels of antioxidants, antioxidant enzymes, and nicotinamide adenine dinucleotide phosphate (NADPH) were synthesized. Quantitative real-time PCR results also verified that D-limonene treatment triggered upregulation of genes involved in the antioxidant system and the regeneration of NADPH at the transcription level in S. cerevisiae. These data indicate that D-limonene treatment results in intracellular ROS accumulation, an important factor in cell death, and several antioxidant mechanisms in S. cerevisiae were enhanced in response to D-limonene treatment.

Use of limonene in countercurrent chromatography: a green alkane substitute.

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Faure, Karine; Bouju, Elodie; Suchet, Pauline; Berthod, Alain

2013-05-07

Counter-current chromatography (CCC) is a preparative separation technique working with the two liquid phases of a biphasic liquid system. One phase is used as the mobile phase when the other, the stationary phase, is held in place by centrifugal fields. Limonene is a biorenewable cycloterpene solvent coming from orange peel waste. It was evaluated as a possible substitute for heptane in CCC separations. The limonene/methanol/water and heptane/methanol/water phase diagrams are very similar at room temperature. The double bonds of the limonene molecule allows for possible π-π interactions with solutes rendering limonene slightly more polar than heptane giving small differences in solute partition coefficients in the two systems. The 24% higher limonene density is a difference with heptane that has major consequences in CCC. The polar and apolar phases of the limonene/methanol/water 10/9/1 v/v have -0.025 g/cm(3) density difference (lower limonene phase) compared to +0.132 g/cm(3) with heptane (upper heptane phase). This precludes the use of this limonene system with hydrodynamic CCC columns that need significant density difference to retain a liquid stationary phase. It is an advantage with hydrostatic CCC columns because density difference is related to the working pressure drop: limonene allows one to work with high centrifugal fields and moderate pressure drop. Limonene has the capability to be a "green" alternative to petroleum-based solvents in CCC applications.

In vitro Antifungal Activity of Limonene against Trichophyton rubrum

OpenAIRE

Chee, Hee Youn; Kim, Hoon; Lee, Min Hee

2009-01-01

In this study, the antifungal activities of limonene against Trichophyton rubrum were evaluated via broth microdilution and vapor contact assays. In both assays, limonene was shown to exert a potent antifungal effect against T. rubrum. The volatile vapor of limonene at concentrations above 1 ?l/800 ml air space strongly inhibited the growth of T. rubrum. The MIC value was 0.5% v/v in the broth microdilution assay. The antifungal activity of limonene against T. rubrum was characterized as a fu...

40 CFR 180.539 - d-Limonene; tolerances for residues.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 23 2010-07-01 2010-07-01 false d-Limonene; tolerances for residues. 180.539 Section 180.539 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... § 180.539 d-Limonene; tolerances for residues. (a) General. (1) The insecticide d-limonene may be safely...

Synthesis of substituted 1,4-diazepines and 1,5-benzodiazepines using an efficient heteropolyacid-catalyzed procedure.

Science.gov (United States)

Kaoua, Rachedine; Bennamane, Norah; Bakhta, Saliha; Benadji, Sihame; Rabia, Cherifa; Nedjar-Kolli, Bellara

2010-12-28

An efficient and improved procedure for the synthesis of 1,4-diazepine and 1,5-benzodiazepine derivatives via the reaction of ketimine intermediates with aldehydes in the presence of Keggin-type heteropolyacids (HPAs) was developed. High yields and short reaction times were obtained for both electron-releasing and electron-withdrawing substituted 1,4-diazepine  and 1,5-benzodiazepines derivatives.

Synthesis of Substituted 1,4-Diazepines and 1,5-Benzodiazepines Using an Efficient Heteropolyacid-Catalyzed Procedure

Directory of Open Access Journals (Sweden)

Sihame Benadji

2010-12-01

Full Text Available An efficient and improved procedure for the synthesis of 1,4-diazepine and 1,5-benzodiazepine derivatives via the reaction of ketimine intermediates with aldehydes in the presence of Keggin-type heteropolyacids (HPAs was developed. High yields and short reaction times were obtained for both electron-releasing and electron-withdrawing substituted 1,4-diazepine  and 1,5-benzodiazepines derivatives.

Metabolic engineering of Escherichia coli for limonene and perillyl alcohol production.

Science.gov (United States)

Alonso-Gutierrez, Jorge; Chan, Rossana; Batth, Tanveer S; Adams, Paul D; Keasling, Jay D; Petzold, Christopher J; Lee, Taek Soon

2013-09-01

Limonene is a valuable monoterpene used in the production of several commodity chemicals and medicinal compounds. Among them, perillyl alcohol (POH) is a promising anti-cancer agent that can be produced by hydroxylation of limonene. We engineered E. coli with a heterologous mevalonate pathway and limonene synthase for production of limonene followed by coupling with a cytochrome P450, which specifically hydroxylates limonene to produce POH. A strain containing all mevalonate pathway genes in a single plasmid produced limonene at titers over 400mg/L from glucose, substantially higher than has been achieved in the past. Incorporation of a cytochrome P450 to hydroxylate limonene yielded approximately 100mg/L of POH. Further metabolic engineering of the pathway and in situ product recovery using anion exchange resins would make this engineered E. coli a potential production platform for any valuable limonene derivative. © 2013 Elsevier Inc. All rights reserved.

Washing effects of limonene on pesticide residues in green peppers.

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Lu, Hai-Yan; Shen, Yan; Sun, Xing; Zhu, Hong; Liu, Xian-Jin

2013-09-01

The presence of pesticide residues in food has caused much concern. The low health risks and environmental impacts of limonene make it a very interesting solvent for use in green chemistry. Washing effects of limonene on pesticide residues of methyl chlorpyrifos, chlorothalonil, chlorpyrifos, fenpropathrin and deltamethrin were investigated in green pepper. Results showed that washing with a low concentration of limonene for 5 min (where LOQ is limit of quantitation) caused 53.67%, limonene for 10 min produced 55.90%, limonene for 5 min was the optimal treatment for elimination of pesticide residues in green pepper, considering effect and treatment time as well as cost. © 2013 Society of Chemical Industry.

Limonene: Aroma of innovation in health and disease.

Science.gov (United States)

Vieira, A J; Beserra, F P; Souza, M C; Totti, B M; Rozza, A L

2018-03-01

Natural products obtained in dietary components may aid the prevention and treatment of a variety of diseases. Reports in the scientific literature have demonstrated that the consumption of terpenes is a successful alternative in the treatment of several diseases, triggering beneficial biological effects in clinical and preclinical studies. The monoterpene limonene is largely used in alimentary items, cleaning products, and it is one of the most frequent fragrances used in cosmetics formulation. The therapeutic effects of limonene have been extensively studied, proving anti-inflammatory, antioxidant, antinociceptive, anticancer, antidiabetic, antihyperalgesic, antiviral, and gastroprotective effects, among other beneficial effects in health. In this review, we collected, presented, and analyzed evidence from the scientific literature regarding the usage of limonene and its activities and underlying mechanisms involved in combating diseases. The highlighting of limonene applications could develop a useful targeting of innovative research in this field as well as the development of a limonene-based phytomedicine which could be used in a variety of conditions of health and disease. Copyright © 2018 Elsevier B.V. All rights reserved.

Effects of limonene on ruminal concentrations, fermentation, and lysine degradation in cattle.

Science.gov (United States)

Samii, S Saed; Wallace, N; Nagaraja, T G; Engstrom, M A; Miesner, M D; Armendariz, C K; Titgemeyer, E C

2016-08-01

Previous in vitro data showed that was inhibited by limonene. We further evaluated effects of limonene on growth of in vitro as well as on ruminal concentrations of in vivo. With in vitro cultivation in anaerobic brain-heart infusion broth, limonene decreased growth of . Thymol also reduced growth of , but it was less effective than limonene. Tylosin effectively reduced growth of in vitro. Although the response over fermentation times and concentrations of antimicrobials differed somewhat between tylosin and limonene, the 2 antimicrobial agents yielded similar inhibitory effects on growth of at concentrations ranging from 6 to 24 mg/L. The effects of limonene on ruminal concentration in vivo were tested in 7 ruminally cannulated heifers (225 kg initial BW) used in a 7 × 4 Youden square design. Treatments included: 1) control, 2) limonene at 10 mg/kg diet DM, 3) limonene at 20 mg/kg diet DM, 4) limonene at 40 mg/kg diet DM, 5) limonene at 80 mg/kg diet DM, 6) CRINA-L (a blend of essential oil components) at 180 mg/kg diet DM, and 7) tylosin at 12 mg/kg diet DM. Each period included 11 d with 10 d washouts between periods. Samples of ruminal contents were collected before treatment initiation and after 4, 7, and 10 d of treatment for measuring by the most probable number method using selective culture medium. Limonene linearly decreased ( = 0.03) ruminal concentration, with the lowest concentration achieved with 40 mg of limonene/kg dietary DM. Limonene tended ( ≤ 0.07) to linearly reduce ruminal molar proportions of propionate and valerate while tending to linearly increase ( ≤ 0.10) those of butyrate and 2-methyl butyrate. Limonene did not affect ruminal NH concentrations or degradation rates of lysine. Neither CRINA-L ( = 0.52) nor tylosin ( = 0.19) affected ruminal concentrations. CRINA-L significantly decreased ruminal concentrations of NH and molar proportions of 3-methyl butyrate, whereas tylosin significantly decreased molar proportions of propionate

The reaction of (R)-limonene with S-thioacids

International Nuclear Information System (INIS)

Mattos, Marcio C.S. de; Bernini, Rafael Berrelho

2007-01-01

The reaction of (R)-limonene with equimolar amount of S-thioacetic or S-thiobenzoic acids in refluxing toluene proceeded regioselectively in anti-Markovnikoff fashion forming 9-[(4R, 8RS)-p-menthenyl] S-thiocarboxylates (71 and 61% yield, respectively). The montmorillonite K-10 clay-catalyzed reaction of (R)-limonene with S-thioacetic acid led to the S-thioester (65%) along with p-menthadienes and p-cymene. It was observed that K-10 clay promoted the isomerization of limonene to p-menthadienes and further disproportionation to p-cymene. (author)

Xanthobacter sp. C20 contains a novel bioconversion pathway for limonene

NARCIS (Netherlands)

Werf, M.J. van der; Keijzer, P.M.; Schaft, P.H. van der

2000-01-01

Xanthobacter sp. C20 was isolated from sediment of the river Rhine using cyclohexane as sole source of carbon and energy. Xanthobacter sp. C20 converted both enantiomers of limonene quantitatively into limonene-8,9-epoxide, a not previously described bioconversion product of limonene. With

Rhodococcus erythropolis DCL14 Contains a Novel Degradation Pathway for Limonene

OpenAIRE

van der Werf, Mariët J.; Swarts, Henk J.; de Bont, Jan A. M.

1999-01-01

Strain DCL14, which is able to grow on limonene as a sole source of carbon and energy, was isolated from a freshwater sediment sample. This organism was identified as a strain of Rhodococcus erythropolis by chemotaxonomic and genetic studies. R. erythropolis DCL14 also assimilated the terpenes limonene-1,2-epoxide, limonene-1,2-diol, carveol, carvone, and (−)-menthol, while perillyl alcohol was not utilized as a carbon and energy source. Induction tests with cells grown on limonene revealed t...

Fast-Dissolving, Prolonged Release, and Antibacterial Cyclodextrin/Limonene-Inclusion Complex Nanofibrous Webs via Polymer-Free Electrospinning.

Science.gov (United States)

Aytac, Zeynep; Yildiz, Zehra Irem; Kayaci-Senirmak, Fatma; San Keskin, Nalan Oya; Kusku, Semran Ipek; Durgun, Engin; Tekinay, Turgay; Uyar, Tamer

2016-10-05

We have proposed a new strategy for preparing free-standing nanofibrous webs from an inclusion complex (IC) of a well-known flavor/fragrance compound (limonene) with three modified cyclodextrins (HPβCD, MβCD, and HPγCD) via electrospinning (CD/limonene-IC-NFs) without using a polymeric matrix. The experimental and computational modeling studies proved that the stoichiometry of the complexes was 1:1 for CD/limonene systems. MβCD/limonene-IC-NF released much more limonene at 37, 50, and 75 °C than HPβCD/limonene-IC-NF and HPγCD/limonene-IC-NF because of the greater amount of preserved limonene. Moreover, MβCD/limonene-IC-NF has released only 25% (w/w) of its limonene, whereas HPβCD/limonene-IC-NF and HPγCD/limonene-IC-NF released 51 and 88% (w/w) of their limonene in 100 days, respectively. CD/limonene-IC-NFs exhibited high antibacterial activity against E. coli and S. aureus. The water solubility of limonene increased significantly and CD/limonene-IC-NFs were dissolved in water in a few seconds. In brief, CD/limonene-IC-NFs with fast-dissolving character enhanced the thermal stability and prolonged the shelf life along with antibacterial properties could be quite applicable in food and oral care applications.

The antioxidant and antigenotoxic properties of citrus phenolics limonene and naringin.

Science.gov (United States)

Bacanlı, Merve; Başaran, A Ahmet; Başaran, Nurşen

2015-07-01

Phenolic compounds not only contribute to the sensory qualities of fruits and vegetables but also exhibit several health protective properties. Limonene and naringin are the most popular phenolics found in Citrus plants. In this study, we investigated the antioxidant capacities of limonene and naringin by the trolox equivalent antioxidant capacity (TEAC) assay and the cytotoxic effects by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay in Chinese hamster fibroblast (V79) cells. The genotoxic potentials of limonene and naringin were evaluated by micronucleus (MN) and alkaline COMET assays in human lymphocytes and V79 cells. Limonene and naringin, were found to have antioxidant activities at concentrations of 2-2000 µM and 5-2000 µM respectively. IC50 values of limonene and naringin were found to be 1265 µM and 9026 µM, respectively. Limonene at the concentrations below 10,000 µM and naringin at the all concentrations studied, have not exerted genotoxic effects in lymphocytes and in V79 cells. Limonene and naringin at all concentrations revealed a reduction in the frequency of MN and DNA damage induced by H2O2. Copyright © 2015 Elsevier Ltd. All rights reserved.

Gamma-radiolysis of chiral molecules: R(+)-limonene, S(-)-limonene and R(-)-a-phellandrene

International Nuclear Information System (INIS)

Cataldo, F.

2004-01-01

Three isomeric chiral terpenes, R(+)-limonene, S(-)-limonene and R(-)-α-phellandrene were γ-radiolyzed in sealed vials at room temperature with a total radiation dose of 317 kGy. The radiolyzed samples were analyzed by FT-IR, electronic absorption spectroscopy, liquid chromatography using a diode-array detector (HPLC-DAD) and by polarimetry. Despite a relatively high radiation dose used, all the chiral molecules selected have shown a low radioracemization rate. This fact and the role played by the impurities in the selective radio-degradation of one of the two enantiomers has been discussed in the context of the origin of chirality in prebiotic molecules and the chirality enhancement in a prebiotic world. The results were also discussed in the frame of the radiosterilization technique of chiral drugs, perfumes and food components. (author)

Plasma metabolomic profiles of breast cancer patients after short-term limonene intervention.

Science.gov (United States)

Miller, Jessica A; Pappan, Kirk; Thompson, Patricia A; Want, Elizabeth J; Siskos, Alexandros P; Keun, Hector C; Wulff, Jacob; Hu, Chengcheng; Lang, Julie E; Chow, H-H Sherry

2015-01-01

Limonene is a lipophilic monoterpene found in high levels in citrus peel. Limonene demonstrates anticancer properties in preclinical models with effects on multiple cellular targets at varying potency. While of interest as a cancer chemopreventive, the biologic activity of limonene in humans is poorly understood. We conducted metabolite profiling in 39 paired (pre/postintervention) plasma samples from early-stage breast cancer patients receiving limonene treatment (2 g QD) before surgical resection of their tumor. Metabolite profiling was conducted using ultra-performance liquid chromatography coupled to a linear trap quadrupole system and gas chromatography-mass spectrometry. Metabolites were identified by comparison of ion features in samples to a standard reference library. Pathway-based interpretation was conducted using the human metabolome database and the MetaCyc database. Of the 397 named metabolites identified, 72 changed significantly with limonene intervention. Class-based changes included significant decreases in adrenal steroids (P limonene resulted in significant changes in several metabolic pathways. Furthermore, pathway-based changes were related to the change in tissue level cyclin D1 expression. Future controlled clinical trials with limonene are necessary to determine the potential role and mechanisms of limonene in the breast cancer prevention setting. ©2014 American Association for Cancer Research.

Histopathological and biochemical assessment of d-limonene-induced liver injury in rats.

Science.gov (United States)

Ramos, Carlos Alberto F; Sá, Rita de Cássia da S; Alves, Mateus F; Benedito, Rubens B; de Sousa, Damião P; Diniz, Margareth de Fátima F M; Araújo, Maria Salete T; de Almeida, Reinaldo N

2015-01-01

The aim of the present work was to develop a biochemical, histologic and immunohistochemical study about the potential hepatotoxic effect of d-limonene - a component of volatile oils extracted from citrus plants. Blood alkaline phosphatase (ALP), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) from d-limonene-treated animals were determined and compared to morphologic hepatic lesions in order to investigate the possible physiopathologic mechanisms involved in the liver toxicity, in experimental animals treated with d-limonene. Wistar rats were randomly divided into seven groups: two control groups (untreated or receiving only vehicle, tween-80); one positive control (vehicle); two experimental groups treated with d-limonene at doses of 25 mg/kg/day and 75 mg/kg/day for 45 days, and two other groups treated with the same doses for 30 days and kept under observation during 30 more days. Biochemical data showed significant reduction in ALT levels in the animals treated with 75 mg/kg of d-limonene. Histological analysis revealed some hepatocyte morphological lesions, including hydropic degeneration, microvesicular steatosis and necrosis, Kupffer cell hyperplasia and incipient fibrosis. By immunohistochemistry, influx of T (CD3+) and cytotoxic (CD8+) lymphocytes was observed in the rats treated with d-limonene at both dose levels. In conclusion, it is possible that d-limonene has been directly responsible for hepatic parenchymal and matrix damage following subchronic treatment with d-limonene.

Biotransformation of limonene by bacteria, fungi, yeasts, and plants

NARCIS (Netherlands)

Duetz, W.A.; Bouwmeester, H.J.; Beilen, J.B.; Witholt, B.

2003-01-01

The past 5 years have seen significant progress in the field of limonene biotransformation, especially with regard to the regiospecificity of microbial biocatalysts. Whereas earlier only regiospecific biocatalysts for the 1,2 position (limonene-1,2-diol) and the 8-position (¿±-terpineol) were

Activity of R(+ limonene against Anisakis larvae

Directory of Open Access Journals (Sweden)

Filippo Giarratana

2015-12-01

Full Text Available The aim of this work is to evaluate the activity of R(+ limonene of against Anisakidae larvae. Its effectiveness was tested in vitro. The results obtained showing a significant activity of the compound against Anisakis larvae, suggesting further investigation on its potential use in the industrial marinating process. In this regard, the use of R(+ limonene in seafood products could be interesting, also due the sensory attributes resulting from its use and its relatively safe status.

Limonene inhibits streptococcal biofilm formation by targeting surface-associated virulence factors.

Science.gov (United States)

Subramenium, Ganapathy Ashwinkumar; Vijayakumar, Karuppiah; Pandian, Shunmugiah Karutha

2015-08-01

The present study explores the efficacy of limonene, a cyclic terpene found in the rind of citrus fruits, for antibiofilm potential against species of the genus Streptococcus, which have been deeply studied worldwide owing to their multiple pathogenic efficacy. Limonene showed a concentration-dependent reduction in the biofilm formation of Streptococcus pyogenes (SF370), with minimal biofilm inhibitory concentration (MBIC) of 400 μg ml - 1. Limonene was found to possess about 75-95 % antibiofilm activity against all the pathogens tested, viz. Streptococcus pyogenes (SF370 and 5 clinical isolates), Streptococcus mutans (UA159) and Streptococcus mitis (ATCC 6249) at 400 μg ml - 1 concentration. Microscopic analysis of biofilm architecture revealed a quantitative breach in biofilm formation. Results of a surface-coating assay suggested that the possible mode of action of limonene could be by inhibiting bacterial adhesion to surfaces, thereby preventing the biofilm formation cascade. Susceptibility of limonene-treated Streptococcus pyogenes to healthy human blood goes in unison with gene expression studies in which the mga gene was found to be downregulated. Anti-cariogenic efficacy of limonene against Streptococcus mutans was confirmed, with inhibition of acid production and downregulation of the vicR gene. Downregulation of the covR, mga and vicR genes, which play a critical role in regulating surface-associated proteins in Streptococcus pyogenes and Streptococcus mutans, respectively, is yet further evidence to show that limonene targets surface-associated proteins. The results of physiological assays and gene expression studies clearly show that the surface-associated antagonistic mechanism of limonene also reduces surface-mediated virulence factors.

Engineering of cyanobacteria for the photosynthetic production of limonene from CO2.

Science.gov (United States)

Kiyota, Hiroshi; Okuda, Yukiko; Ito, Michiho; Hirai, Masami Yokota; Ikeuchi, Masahiko

2014-09-20

Isoprenoids, major secondary metabolites in many organisms, are utilized in various applications. We constructed a model photosynthetic production system for limonene, a volatile isoprenoid, using a unicellular cyanobacterium that expresses the plant limonene synthase. This system produces limonene photosynthetically at a nearly constant rate and that can be efficiently recovered using a gas-stripping method. This production does not affect the growth of the cyanobacteria and is markedly enhanced by overexpression of three enzymes in the intrinsic pathway to provide the precursor of limonene, geranyl pyrophosphate. The photosynthetic production of limonene in our system is more or less sustained from the linear to stationary phase of cyanobacterial growth for up to 1 month. Copyright © 2014 Elsevier B.V. All rights reserved.

Chemoselective Preparation of 1,1-Diacetates from Aldehydes, Mediated by a Keggin Heteropolyacid Under Solvent Free Conditions at Room Temperature

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G. Romanelli

2007-01-01

Full Text Available A simple, general and efficient method has been developed for the conversion of aldehydes to 1,1-diacetates using acetic anhydride, a catalytic amount of non commercial Keggin heteropolyacid (H6 PalMo11O40 (1% mol in solvent free conditions at room temperature. Aromatic and aliphatic, simple and conjugated aldehydes were protected with excellent yields.

Investigation into state of phosphomolybdovanadic heteropolyacids in aqueous solutions by the NMR method

International Nuclear Information System (INIS)

Maksimovskaya, R.I.; Fedotov, M.A.; Mastikhin, V.M.; Kuznetsova, L.I.; Matveev, K.I.

1978-01-01

The methods of 31 P, 51 V, and 17 O NMR have been used for studying the solutions of phospho-molybdenum-vanadium heteropolyacids (HPA) with x=0,1,2,3 (HPA-x) and their mixture with changing concentration, acidity, temperature, and upon partial reduction for separating the lines corresponding to HPA with a certain x. It has been found that in aqueous solutions HPA is present as a mixture of HPA of different compositions; the relationship has been observed between chemical shifts of the lines and the solution acidity which is of a different character for HPA with different x. This allows to make a conclusion about the mechanism of HPA protonation

Contact Allergy to Hydroperoxides of Linalool and D-Limonene in a US Population.

Science.gov (United States)

Nath, Neel Som; Liu, Beiyu; Green, Cynthia; Atwater, Amber Reck

Linalool and D-limonene are common fragrance ingredients that readily oxidize on exposure to air. The resulting hydroperoxides of linalool and D-limonene have been shown to have high frequencies of positive patch test reactions in several European and international studies. The aim of the study was to investigate the prevalence of contact allergy to the hydroperoxides of linalool and D-limonene in a US population. In this retrospective study, 103 patients with suspected fragrance allergy were patch tested to linalool 10% petrolatum (pet), hydroperoxides of linalool 1% pet, D-limonene 10% pet, and/or the hydroperoxides of D-limonene 0.3% pet between July 9, 2014, and October 25, 2016. In this study, the frequency of positive patch test reactions to the hydroperoxides of linalool is 20% (19/96), and the frequency of positive reactions to the hydroperoxides of D-limonene is 8% (7/90). These high frequencies suggest that patch testing to the hydroperoxides of linalool and limonene should be performed in all patients with suspected fragrance allergy.

Water accelerated transformation of d-limonene induced by ultraviolet irradiation and air exposure.

Science.gov (United States)

Li, Li Jun; Hong, Peng; Jiang, Ze Dong; Yang, Yuan Fan; Du, Xi Ping; Sun, Hao; Wu, Li Ming; Ni, Hui; Chen, Feng

2018-01-15

d-Limonene is a fragrant chemical that widely exists in aromatic products. Isotopic labelling of water molecules plus GC-MS and GC-PCI-Q-TOF analyses were used to investigate the influence of water molecules on chemical transformation of d-limonene induced by UV irradiation and air exposure. The results showed that the synergistic effect of UV irradiation, air exposure and water presence could facilitate d-limonene transformation into the limonene oxides: p-mentha-2,8-dienols, hydroperoxides, carveols, l-carvone and carvone oxide. UV irradiation, air exposure, or water alone, however, caused negligible d-limonene transformation. With the aid of isotopic labelling of water and oxygen molecules, it was found that water molecules were split into hydrogen radicals and hydroxyl radicals, and the hydrogen radicals, in particular, promoted the transformation reactions. This study has elucidated the mechanism and factors that influence the transformation of d-limonene, which will benefit industries involved in production and storage of d-limonene-containing products. Copyright © 2017 Elsevier Ltd. All rights reserved.

Physio-pharmacological Investigations About the Anti-inflammatory and Antinociceptive Efficacy of (+)-Limonene Epoxide.

Science.gov (United States)

de Almeida, Antonia Amanda Cardoso; Silva, Renan Oliveira; Nicolau, Lucas Antonio Duarte; de Brito, Tarcísio Vieira; de Sousa, Damião Pergentino; Barbosa, André Luiz Dos Reis; de Freitas, Rivelilson Mendes; Lopes, Luciano da Silva; Medeiros, Jand-Venes Rolim; Ferreira, Paulo Michel Pinheiro

2017-04-01

D-limonene epoxidation generates (+)-limonene epoxide, an understudied compound in the pharmacologically point of view. Herein, we investigated the anti-inflammatory and antinociceptive potentialities of (+)-limonene epoxide and suggested a mechanism of action. The anti-inflammatory potential was analyzed using agents to induce paw edema, permeability, and myeloperoxidase (MPO) activity. Pro-inflammatory cytokines and cell migration of peritoneal cells were also assessed. Antinociceptive effects were evaluated by writhing test induced by acetic acid, formalin, and hot plate assays and contribution of opioid pathways. Pretreated animals with (+)-limonene epoxide showed reduced carrageenan-induced paw edema in all doses (25, 50, and 75 mg/kg) (P Limonene epoxide diminished abdominal contortions induced by acetic acid (78.9%) and paw licking times in both 1 (41.8%) and 2 (51.5%) phases and a pretreatment with naloxone (3 mg/kg) reverted the antinociceptive action in morphine- and (+)-limonene epoxide-treated groups (P limonene epoxide inhibited release/activity of inflammatory mediators, vascular permeability, migration of neutrophils and displayed systemic and peripheral analgesic-dependent effects of the opioid system.

An international multicentre study on the allergenic activity of air-oxidized R-limonene

DEFF Research Database (Denmark)

Bråred Christensson, Johanna; Andersen, Klaus Ejner; Bruze, Magnus

2013-01-01

Background. Limonene is a common fragrance terpene that, in its pure form, is not allergenic or is a very weak allergen. However, limonene autoxidizes on air exposure, and the oxidation products can cause contact allergy. Oxidized R-limonene has previously been patch tested in multicentre studies......, giving 2-3% positive patch test reactions in consecutive patients. Objectives. To investigate whether oxidized R-limonene 3.0% in petrolatum, with a stable concentration of the main haptens, limonene hydroperoxides (Lim-OOHs), could be a useful tool for the detection of contact allergy...... in an international setting. Methods. Oxidized R-limonene 3.0% (Lim-OOHs 0.33%) pet. was tested in 2900 consecutive dermatitis patients in Denmark, the United Kingdom, Singapore, Spain, Sweden, and Australia. Results. Overall, 5.2% (range 2.3-12.1%) of the patients showed a positive patch test reaction to oxidized R...

Limonene--A Natural Insecticide.

Science.gov (United States)

Beatty, Joseph H.

1986-01-01

Describes a high school chemistry student's research project in which limonene was isolated from the oil of lemons and oranges. Outlines the students' tests on the use of this chemical as an insecticide. Discusses possible extensions of the exercises based on questions generated by the students. (TW)

Capturing of the monoterpene olefin limonene produced in Saccharomyces cerevisiae

NARCIS (Netherlands)

Jongedijk, E.J.; Cankar, K.; Ranzijn, J.; Krol, van der A.R.; Bouwmeester, H.J.; Beekwilder, M.J.

2015-01-01

Monoterpene olefins such as limonene are plant compounds with applications as flavouring and fragrance agents, as solvents and potentially also in polymer and fuel chemistry. We engineered baker's yeast Saccharomyces cerevisiae to express a (-)-limonene synthase from Perilla frutescens and a

Effects of d- and l-limonene on the pregnant rat myometrium in vitro.

Science.gov (United States)

Hajagos-Tóth, Judit; Hódi, Ágnes; Seres, Adrienn B; Gáspár, Róbert

2015-10-01

To study the effects of d- and l-limonene on pregnant rat myometrial contractility in vitro, and investigate how these effects are modified by other agents. D- and l-limonene (10(-13)-10(-8) M) caused myometrial contraction in a dose-dependent manner. Contractions of uterine rings from 22-day-pregnant rats were measured in an organ bath in the presence of d- or l-limonene (10(-13)-10(-8) M) and nifedipine (10(-8) M), tetraethyl-ammonium (10(-3) M), theophylline (10(-5) M), or paxilline (10(-5) M). Uterine cyclic adenosine monophosphate (cAMP) level was detected by enzyme immunoassay. Oxidative damage was induced by methylglyoxal (3×10(-2) M) and the alteration was measured via noradrenaline (1×10(-9) to 3×10(-5) M) -induced contractions. Pre-treatment with nifedipine (10(-8) M), tetraethylammonium (10(-3) M), and theophylline (10(-5) M) attenuated the contracting effect of d- and l-limonene, while in the presence of paxilline (10(-5) M) d- and l-limonene were ineffective. The two enantiomers decreased the myometrial cAMP level, but after paxilline pretreatment the cAMP level was not altered compared with the control value. Additionally, l-limonene (10(-6) M) diminished consequences of oxidative damage caused by methylglyoxal (3×10(-2) M) on contractility, whereas d-limonene was ineffective. Our findings suggest that l-limonene has an antioxidant effect and that both d-and l-limonene cause myometrial contraction through activation of the A2A receptor and opening of the voltage-gated Ca(2+) channel. It is possible that limonene-containing products increase the pregnant uterus contractility and their use should be avoided during pregnancy.

Fragrant starch-based films with limonene

Directory of Open Access Journals (Sweden)

Adrian K. Antosik

2017-02-01

Full Text Available Novel fragrant starch-based films with limonene were successfully prepared. Biodegradable materials of natural origin were used and the process was relatively simple and inexpensive. The effect of limonene on physicochemical properties of starch-based films (moisture absorption, solubility in water, wettability, mechanical properties were compared to glycerol plasticized system. Taking into consideration that the obtained materials could also exhibit bactericidal and fungicidal properties, the studies with Escherichia coli, Candida albicans and Aspergillus niger were performed. Such a material could potentially find application in food packaging (e.g. masking unpleasant odors, hydrophilic starch film would prevent food drying, or in agriculture (e.g. for seed encapsulated tapes.

d-limonene exhibits antitumor activity by inducing autophagy and apoptosis in lung cancer.

Science.gov (United States)

Yu, Xiao; Lin, Hongyan; Wang, Yu; Lv, Wenwen; Zhang, Shuo; Qian, Ying; Deng, Xiaobei; Feng, Nannan; Yu, Herbert; Qian, Biyun

2018-01-01

d-limonene is a plant extract with widespread application, and it has been recently reported to have antiproliferative and proapoptotic effects on cancer cells. However, the mechanisms by which d-limonene achieves these effects, especially in lung cancer, are not entirely clear. Therefore, the goal of this study was to examine the effects of d-limonene on lung cancer and explore its mechanisms of action. We examined the therapeutic effects of d-limonene on lung cancer cells and in a xenograft animal model by characterizing its effects on the pathways of apoptosis and autophagy. Cell proliferation was measured using the Cell Counting Kit-8, and apoptosis was determined by flow cytometric analysis. Levels of LC3 puncta, an autophagy marker, were analyzed by laser scanning confocal microscopy. Autophagy and apoptosis-related gene expression were assessed by real-time quantitative polymerase chain reaction and Western blot. d-limonene inhibited the growth of lung cancer cells and suppressed the growth of transplanted tumors in nude mice. Expression of apoptosis and autophagy-related genes were increased in tumors after treatment with d-limonene. Furthermore, the use of chloroquine, an autophagy inhibitor, and knockdown of the atg5 gene, suppressed the apoptosis induced by d-limonene. d-limonene may have a therapeutic effect on lung cancer as it can induce apoptosis of lung cancer cells by promoting autophagy.

Toxicological analysis of limonene reaction products using an in vitro exposure system

Science.gov (United States)

Anderson, Stacey E.; Khurshid, Shahana S.; Meade, B. Jean; Lukomska, Ewa; Wells, J.R.

2015-01-01

Epidemiological investigations suggest a link between exposure to indoor air chemicals and adverse health effects. Consumer products contain reactive chemicals which can form secondary pollutants which may contribute to these effects. The reaction of limonene and ozone is a well characterized example of this type of indoor air chemistry. The studies described here characterize an in vitro model using an epithelial cell line (A549) or differentiated epithelial tissue (MucilAir™). The model is used to investigate adverse effects following exposure to combinations of limonene and ozone. In A549 cells, exposure to both the parent compounds and reaction products resulted in alterations in inflammatory cytokine production. A one hour exposure to limonene + ozone resulted in decreased proliferation when compared to cells exposed to limonene alone. Repeated dose exposures of limonene or limonene + ozone were conducted on MucilAir™ tissue. No change in proliferation was observed but increases in cytokine production were observed for both the parent compounds and reaction products. Factors such as exposure duration, chemical concentration, and sampling time point were identified to influence result outcome. These findings suggest that exposure to reaction products may produce more severe effects compared to the parent compound. PMID:23220291

A novel mechanism for antiglycative action of limonene through stabilization of protein conformation.

Science.gov (United States)

Joglekar, Madhav M; Panaskar, Shrimant N; Chougale, Ashok D; Kulkarni, Mahesh J; Arvindekar, Akalpita U

2013-10-01

Inhibition of protein glycation is known to ameliorate secondary complications in diabetes. In the present study antiglycative properties of limonene, a natural product, were evaluated using BSA as a model protein. AMG (aminoguanidine) was used as a positive control. Measurement of total AGEs (Advanced Glycation End-products) and specific AGEs revealed that limonene could inhibit protein glycation to the extent of 56.3% and 75.1% respectively at 50 μM concentration as against 54.4% and 82.2% by AMG at 1 mM. Congo red binding and CD (Circular Dichroism) analysis revealed inhibition of α-helix to β-sheet transition wherein 18.5% β-sheet structures were observed in glycated BSA (bovine serum albumin) as against 4.9% with limonene. Glycation of protein in the presence of urea was enhanced by 18%, while in the presence of limonene it was reduced by 23% revealing the stabilizing effect of limonene. Electrophoretic mobility was similar to the normal control and a zeta potential value of -12.1 mV as against -15.1 mV in diabetic control was observed. Inhibition of glycation in limonene treated samples was confirmed through LC-MS analysis wherein AGEs such as pentosidine, CML (N(ε)-(carboxymethyl)lysine), CEL (N(ε)-(carboxyethyl)lysine), MOLD (methylglyoxal-lysine dimer) and imidazolone observed in glycated samples were absent in limonene treated samples. PatchDock studies revealed that limonene could bind to the major glycation sites IB, IIA and IIB sub domains and AMG to the IIIA sub domain. Thus limonene is a potent protein glycation inhibitor that prevents protein glycation through a novel mechanism of stabilization of protein structure through hydrophobic interactions.

Limonene and its ozone-initiated reaction products attenuate allergic lung inflammation in mice.

Science.gov (United States)

Hansen, Jitka S; Nørgaard, Asger W; Koponen, Ismo K; Sørli, Jorid B; Paidi, Maya D; Hansen, Søren W K; Clausen, Per Axel; Nielsen, Gunnar D; Wolkoff, Peder; Larsen, Søren Thor

2016-11-01

Inhalation of indoor air pollutants may cause airway irritation and inflammation and is suspected to worsen allergic reactions. Inflammation may be due to mucosal damage, upper (sensory) and lower (pulmonary) airway irritation due to activation of the trigeminal and vagal nerves, respectively, and to neurogenic inflammation. The terpene, d-limonene, is used as a fragrance in numerous consumer products. When limonene reacts with the pulmonary irritant ozone, a complex mixture of gas and particle phase products is formed, which causes sensory irritation. This study investigated whether limonene, ozone or the reaction mixture can exacerbate allergic lung inflammation and whether airway irritation is enhanced in allergic BALB/cJ mice. Naïve and allergic (ovalbumin sensitized) mice were exposed via inhalation for three consecutive days to clean air, ozone, limonene or an ozone-limonene reaction mixture. Sensory and pulmonary irritation was investigated in addition to ovalbumin-specific antibodies, inflammatory cells, total protein and surfactant protein D in bronchoalveolar lavage fluid and hemeoxygenase-1 and cytokines in lung tissue. Overall, airway allergy was not exacerbated by any of the exposures. In contrast, it was found that limonene and the ozone-limonene reaction mixture reduced allergic inflammation possibly due to antioxidant properties. Ozone induced sensory irritation in both naïve and allergic mice. However, allergic but not naïve mice were protected from pulmonary irritation induced by ozone. This study showed that irritation responses might be modulated by airway allergy. However, aggravation of allergic symptoms was observed by neither exposure to ozone nor exposure to ozone-initiated limonene reaction products. In contrast, anti-inflammatory properties of the tested limonene-containing pollutants might attenuate airway allergy.

Coupling limonene formation and oxyfunctionalization by mixed-culture resting cell fermentation.

Science.gov (United States)

Willrodt, Christian; Hoschek, Anna; Bühler, Bruno; Schmid, Andreas; Julsing, Mattijs K

2015-09-01

Metabolic engineering strategies mark a milestone for the fermentative production of bulk and fine chemicals. Yet, toxic products and volatile reaction intermediates with low solubilities remain challenging. Prominent examples are artificial multistep pathways like the production of perillyl acetate (POHAc) from glucose via limonene. For POHAc, these limitations can be overcome by mixed-culture fermentations. A limonene biosynthesis pathway and cytochrome P450 153A6 (CYP153A6) as regioselective hydroxylase are used in two distinct recombinant E. coli. POHAc formation from glucose in one recombinant cell was hindered by ineffective coupling of limonene synthesis and low rates of oxyfunctionalization. The optimization of P450 gene expression led to the formation of 6.20 ± 0.06 mg gcdw (-1) POHAc in a biphasic batch cultivation with glucose as sole carbon and energy source. Increasing the spatial proximity between limonene synthase and CYP153A6 by a genetic fusion of both enzymes changed the molar limonene/POHAc ratio from 3.2 to 1.6. Spatial separation of limonene biosynthesis from its oxyfunctionalization improved POHAc concentration 3.3-fold to 21.7 mg L(-1) as compared to a biphasic fermentation. Mixed-cultures of E. coli BL21 (DE3) containing the limonene biosynthesis pathway and E. coli MG1655 harboring either CYP153A6, or alternatively a cymene monooxygenase, showed POHAc formation rates of 0.06 or 0.11 U gcdw (-1) , respectively. This concept provides a novel framework for fermentative syntheses involving toxic, volatile, or barely soluble compounds or pathway intermediates. © 2015 Wiley Periodicals, Inc.

Fumigant and Repellent Activity of Limonene Enantiomers Against Tribolium confusum du Val.

Science.gov (United States)

Malacrinò, A; Campolo, O; Laudani, F; Palmeri, V

2016-10-01

The use of pesticides, as carried out in the last 50 years, caused several negative environmental and human health consequences, leading to the development of alternative techniques to control pests, such as the use of compounds of plant origin. In this study, we assessed the fumigant and repellent activity of both the enantiomers of limonene, a monoterpene usually found in many plant species, against Tribolium confusum du Val. We tested both molecules at different doses, air temperatures, and in absence and presence of flour. R-(+)-limonene resulted more effective than S-(-)-limonene; indeed, it was able to reach 100% of efficacy at a concentration of 85 mg/L air when tested at different temperatures without flour. Data showed a positive relationship between efficacy and temperature, and a negative effect of the presence of debris on the bioactivity of limonene. Furthermore, repellency trials reported a higher activity of R-(+)-limonene compared to the other enantiomer.

Catalytic activity of supported silver and potassium salts of tungstophosphoric acid in dehydration of ethanol

International Nuclear Information System (INIS)

Haber, J.; Matachowski, L.; Pamin, K.; Napruszewska, B.

2002-01-01

Potassium and silver salts of tungstophosphoric acid (HPW) have been supported on silica. Two series of potassium and silver salts of tungstophosphoric acid K x H 3-x PW 12 O 40 and Ag x H 3-x PW 12 O 40 where x = 1;2;3 supported on silica were prepared using incipient wetness method. In a typical synthesis, the heteropolyacid which after deposition on silica was washed with water to remove the part of heteropolyacid not bound to the support was reacted with silver or potassium salt. The vapor-phase dehydration of ethanol was employed as a test reaction. All the catalytic tests were carried out in a conventional flow type reactor, under atmospheric pressure, in the temperature range 125-500 o C. The results of these studies were used to explain the differences between the catalytic activities of heteropolysalts of potassium and silver supported on silica. (author)

Tailoring the Synergistic Bronsted-Lewis acidic effects in Heteropolyacid catalysts: Applied in Esterification and Transesterification Reactions

OpenAIRE

Tao, Meilin; Xue, Lifang; Sun, Zhong; Wang, Shengtian; Wang, Xiaohong; Shi, Junyou

2015-01-01

In order to investigate the influences of Lewis metals on acidic properties and catalytic activities, a series of Keggin heteropolyacid (HPA) catalysts, HnPW11MO39 (M = TiIV, CuII, AlIII, SnIV, FeIII, CrIII, ZrIV and ZnII; for Ti and Zr, the number of oxygen is 40), were prepared and applied in the esterification and transesterification reactions. Only those cations with moderate Lewis acidity had a higher impact. Ti Substituted HPA, H5PW11TiO40, posse lower acid content compared with TixH3−4...

Protective effects of D-Limonene against transient cerebral ischemia in stroke-prone spontaneously hypertensive rats.

Science.gov (United States)

Wang, Xifeng; Li, Gang; Shen, Wei

2018-01-01

Stroke is a leading cause of disability and death world-wide and there is currently a lack of effective treatments for acute stroke. D-Limonene is a common natural monocyclic monoterpene possessing various activities. The present study aimed to evaluate the therapeutic efficacy of D-limonene against ischemia-associated cerebral injury in hypertensive SHRsp rats. Although systolic blood pressure was not altered by ischemia, D-Limonene decreased the systolic blood pressure of SHRsp rats following stroke. Induction of stroke resulted in increased escape latency time, decreased time spent in the target quadrant in the probe trial, decreased capacity to distinguish between familiar objects and novel objects, and increased sensory neglect in the SHRsp rat, however these symptoms were significantly inhibited by D-limonene. D-limonene also decreased the cerebral infarct size in the SHRsp rats following stroke. D-Limonene markedly decreased the mRNA expression of interleukin-1β, monocyte chemoattractant protein-1 and cyclooxygenase-2 in SHRsp rats following stroke. The mRNA expression of vascular endothelial growth factor in the brain of SHRsp rats following stroke was significantly increased by D-Limonene. D-Limonene increased the activities of superoxide dismutase and catalase, decreased the malondialdehyde level, increased glutathione content and reduced the DHE-staining in SHRsp rats following stroke. Overall, inhibition of cerebral inflammation, vascular remodeling and antioxidant activities of D-Limonene may be involved in the protective effects against ischemia-induced damage in SHRsp rats. The present study identified D-Limonene as a potential therapeutic candidate for treatment of stroke-associated cerebral and vascular damage under conditions of hypertension.

Determination of d-limonene in adipose tissue by gas chromatography-mass spectrometry

Science.gov (United States)

Miller, Jessica A.; Hakim, Iman A.; Thomson, Cynthia; Thompson, Patricia; Chow, H-H. Sherry

2008-01-01

We developed a novel method for analyzing d-limonene levels in adipose tissue. Fat samples were subjected to saponification followed by solvent extraction. d-Limonene in the sample extract was analyzed using gas chromatography-mass spectrometry (GC-MS) with selected ion monitoring. Linear calibration curves were established over the mass range of 79.0-2,529 ng d-limonene per 0.1 grams of adipose tissue. Satisfactory within day precision (RSD 6.7 to 9.6%) and accuracy (% difference of −2.7 to 3.8%) and between day precision (RSD 6.0 to 10.7%) and accuracy (% difference of 1.8 to 2.6%) were achieved. The assay was successfully applied to human fat biopsy samples from a d-limonene feeding trial. PMID:18571481

SOA from limonene: role of NO3 in its generation and degradation

Directory of Open Access Journals (Sweden)

R. Tillmann

2011-04-01

Full Text Available The formation of organic nitrates and secondary organic aerosol (SOA were monitored during the NO3 + limonene reaction in the atmosphere simulation chamber SAPHIR at Research Center Jülich. The 24-h run began in a purged, dry, particle-free chamber and comprised two injections of limonene and oxidants, such that the first experiment measured SOA yield in the absence of seed aerosol, and the second experiment yields in the presence of 10 μg m−3 seed organic aerosol. After each injection, two separate increases in aerosol mass were observed, corresponding to sequential oxidation of the two limonene double bonds. Analysis of the measured NO3, limonene, product nitrate concentrations, and aerosol properties provides mechanistic insight and constrains rate constants, branching ratios and vapor pressures of the products. The organic nitrate yield from NO3 + limonene is ≈30%. The SOA mass yield was observed to be 25–40%. The first injection is reproduced by a kinetic model. PMF analysis of the aerosol composition suggests that much of the aerosol mass results from combined oxidation by both O3 and NO3, e.g., oxidation of NO3 + limonene products by O3. Further, later aerosol nitrate mass seems to derive from heterogeneous uptake of NO3 onto unreacted aerosol alkene.

Allergy to oxidized limonene and linalool is frequent in the U.K.

Science.gov (United States)

Audrain, H; Kenward, C; Lovell, C R; Green, C; Ormerod, A D; Sansom, J; Chowdhury, M M U; Cooper, S M; Johnston, G A; Wilkinson, M; King, C; Stone, N; Horne, H L; Holden, C R; Wakelin, S; Buckley, D A

2014-08-01

The oxidized forms of the fragrance terpenes limonene and linalool are known to cause allergic contact dermatitis. Significant rates of contact allergy to these fragrances have been reported in European studies and in a recent worldwide study. Patch testing to oxidized terpenes is not routinely carried out either in the U.K. or in other centres internationally. To investigate the prevalence of contact allergy to oxidized limonene and linalool in the U.K. Between 1 August 2011 and 31 December 2012, 4731 consecutive patients in 13 U.K. dermatology departments were tested for hydroperoxides of limonene 0·3% pet., hydroperoxides of linalool 1·0% pet., stabilized limonene 10·0% pet. and stabilized linalool 10·0% pet. Doubtful (?+) and equivocal (±) reactions were grouped together as irritant reactions. Two hundred and thirty-seven patients (5·0%) had a positive patch test reaction to hydroperoxides of limonene 0·3% pet. and 281 (5·9%) to hydroperoxides of linalool 1·0% pet. Irritant reactions to one or both oxidized terpenes were found in 242 patients (7·3%). Eleven patients (0·2%) had a positive patch test reaction to the stabilized terpenes alone. This large, multicentre U.K. audit shows a significant rate of allergy to the hydroperoxides of limonene and linalool plus a high rate of irritant reactions. Testing to the oxidized forms alone captures the majority (97·0%; 411 of 422) of positive reactions; testing to nonoxidized terpenes appears to be less useful. We recommend that the hydroperoxides of limonene and linalool be added to an extended baseline patch test series. © 2014 British Association of Dermatologists.

Antibacterial Activity and Physical Properties of Fish Gelatin-Chitosan Edible Films Supplemented with D-Limonene

Directory of Open Access Journals (Sweden)

Yunzhen Yao

2017-01-01

Full Text Available Fish gelatin-chitosan edible films with D-limonene were successfully prepared, which exhibited exceptional mechanical properties and antimicrobial activity. It has been demonstrated that water-soluble chitosan, fish gelatin, and D-limonene could be a candidate precursor to prepare low cost and high-performance edible food packaging material. The results showed that D-limonene in the films could effectively resist the penetration of light and water because of its hydrophobicity. Moreover, the elongation at break (EAB increased with the addition of D-limonene, which indicated that D-limonene served as a strong plasticizer for the film. Microscopic characterization showed that D-limonene was uniformly distributed in the as-prepared film. And we found that the film exhibited strong antibacterial activity against Escherichia coli (E. coli. All the results indicate that the as-prepared film could be a promising food packaging.

Photochemistry of limonene secondary organic aerosol studied with chemical ionization mass spectrometry

Science.gov (United States)

Pan, Xiang

Limonene is one of the most abundant monoterpenes in the atmosphere. Limonene easily reacts with gas-phase oxidants in air such as NO3, ozone and OH. Secondary organic aerosol (SOA) is formed when low vapor pressure products condense into particles. Chemicals in SOA particles can undergo further reactions with oxidants and with solar radiation that significantly change SOA composition over the course of several days. The goal of this work was to characterize radiation induced reaction in SOA. To perform experiments, we have designed and constructed an Atmospheric Pressure Chemical Ionization Mass Spectrometer (APCIMS) coupled to a photochemical cell containing SOA samples. In APCIMS, (H2O)nH 3O+ clusters are generated in a 63Ni source and react with gaseous organic analytes. Most organic chemicals are not fragmented by the ionization process. We have focused our attention on limonene SOA prepared in two different ways. The first type of SOA is produced by oxidation of limonene by ozone; and the second type of SOA is formed by the NO3-induced oxidation of limonene. They model the SOA formed under daytime and nighttime conditions, respectively. Ozone initiated oxidation is the most important chemical sink for limonene both indoors, where it is used for cleaning purposes, and outdoors. Terpenes are primarily oxidized by reactions with NO3 at night time. We generated limonene SOA under different ozone and limonene concentrations. The resulting SOA samples were exposed to wavelength-tunable radiation in the UV-Visible range between 270 nm and 630 nm. The results show that the photodegradation rates strongly depend on radiation wavelengths. Gas phase photodegradation products such as acetone, formaldehyde, acetaldehyde, and acetic acid were shown to have different production rates for SOA formed in different concentration conditions. Even for SOA prepared under the lowest concentrations, the SOA photodegradation was efficient. The conclusion is that exposure of SOA to

Safety and Feasibility of Topical Application of Limonene as a Massage Oil to the Breast.

Science.gov (United States)

Miller, Jessica A; Thompson, Patricia A; Hakim, Iman A; Lopez, Ana Maria; Thomson, Cynthia A; Chew, Wade; Hsu, Chiu-Hsieh; Chow, H-H Sherry

2012-10-01

Limonene, a major component in citrus oil, has demonstrated anti-cancer effects in preclinical mammary cancer models. However, the effective oral dose translates to a human dose that may not be feasible for chronic dosing. We proposed to evaluate topical application of limonene to the breast as an alternative dosing strategy. We conducted a mouse disposition study to determine whether limonene would be bio available in the mammary tissue after topical application. SKH-1 mice received topical or oral administration of limonene in the form of orange oil every day for 4 weeks. Plasma and mammary pads were collected 4 hrs after the final dosing. We also conducted an exploratory clinical study to evaluate the safety and feasibility of topically applied limonene in the form of orange oil to the breast. Healthy women were recruited to apply orange oil containing massage oil to their breasts daily for four weeks. Safety and feasibility were assessed by reported adverse events, clinical labs, and usage compliance. Pre and post-intervention nipple aspirate fluid (NAF) and plasma were collected for limonene concentration determination. The mouse disposition study showed that topical and oral orange oil administration resulted in similar mammary tissue disposition of limonene with no clinical signs of toxicity. In the clinical study, the topical application of limonene containing massage oil to the breast was found to be safe with high levels of usage compliance for daily application, although NAF and plasma limonene concentrations were not significantly changed after the massage oil application. Our studies showed that limonene is bio available in mammary tissue after topical orange oil application in mice and this novel route of administration to the breast is safe and feasible in healthy women.

Mechanism of bacterial inactivation by (+-limonene and its potential use in food preservation combined processes.

Directory of Open Access Journals (Sweden)

Laura Espina

Full Text Available This work explores the bactericidal effect of (+-limonene, the major constituent of citrus fruits' essential oils, against E. coli. The degree of E. coli BJ4 inactivation achieved by (+-limonene was influenced by the pH of the treatment medium, being more bactericidal at pH 4.0 than at pH 7.0. Deletion of rpoS and exposure to a sub-lethal heat or an acid shock did not modify E. coli BJ4 resistance to (+-limonene. However, exposure to a sub-lethal cold shock decreased its resistance to (+-limonene. Although no sub-lethal injury was detected in the cell envelopes after exposure to (+-limonene by the selective-plating technique, the uptake of propidium iodide by inactivated E. coli BJ4 cells pointed out these structures as important targets in the mechanism of action. Attenuated Total Reflectance Infrared Microspectroscopy (ATR-IRMS allowed identification of altered E. coli BJ4 structures after (+-limonene treatments as a function of the treatment pH: β-sheet proteins at pH 4.0 and phosphodiester bonds at pH 7.0. The increased sensitivity to (+-limonene observed at pH 4.0 in an E. coli MC4100 lptD4213 mutant with an increased outer membrane permeability along with the identification of altered β-sheet proteins by ATR-IRMS indicated the importance of this structure in the mechanism of action of (+-limonene. The study of mechanism of inactivation by (+-limonene led to the design of a synergistic combined process with heat for the inactivation of the pathogen E. coli O157:H7 in fruit juices. These results show the potential of (+-limonene in food preservation, either acting alone or in combination with lethal heat treatments.

Mechanism of Bacterial Inactivation by (+)-Limonene and Its Potential Use in Food Preservation Combined Processes

Science.gov (United States)

Espina, Laura; Gelaw, Tilahun K.; de Lamo-Castellví, Sílvia; Pagán, Rafael; García-Gonzalo, Diego

2013-01-01

This work explores the bactericidal effect of (+)-limonene, the major constituent of citrus fruits' essential oils, against E. coli. The degree of E. coli BJ4 inactivation achieved by (+)-limonene was influenced by the pH of the treatment medium, being more bactericidal at pH 4.0 than at pH 7.0. Deletion of rpoS and exposure to a sub-lethal heat or an acid shock did not modify E. coli BJ4 resistance to (+)-limonene. However, exposure to a sub-lethal cold shock decreased its resistance to (+)-limonene. Although no sub-lethal injury was detected in the cell envelopes after exposure to (+)-limonene by the selective-plating technique, the uptake of propidium iodide by inactivated E. coli BJ4 cells pointed out these structures as important targets in the mechanism of action. Attenuated Total Reflectance Infrared Microspectroscopy (ATR-IRMS) allowed identification of altered E. coli BJ4 structures after (+)-limonene treatments as a function of the treatment pH: β-sheet proteins at pH 4.0 and phosphodiester bonds at pH 7.0. The increased sensitivity to (+)-limonene observed at pH 4.0 in an E. coli MC4100 lptD4213 mutant with an increased outer membrane permeability along with the identification of altered β-sheet proteins by ATR-IRMS indicated the importance of this structure in the mechanism of action of (+)-limonene. The study of mechanism of inactivation by (+)-limonene led to the design of a synergistic combined process with heat for the inactivation of the pathogen E. coli O157:H7 in fruit juices. These results show the potential of (+)-limonene in food preservation, either acting alone or in combination with lethal heat treatments. PMID:23424676

Theoretical Investigation of the NO3 Radical Addition to Double Bonds of Limonene

Science.gov (United States)

Jiang, Lei; Wang, Wei; Xu, Yi-Sheng

2009-01-01

The addition reactions of NO3 to limonene have been investigated using ab initio methods. Six different possibilities for NO3 addition to the double bonds, which correspond to the two C–C double bonds (endocyclic or exocyclic) have been considered. The negative activation energies for the addition of NO3 to limonene are calculated and the energies of NO3-limonene radical adducts are found to be 14.55 to 20.17 kcal mol-1 more stable than the separated NO3 and limonene at the CCSD(T)/6–31G(d) + CF level. The results also indicate that the endocyclic addition reaction is more energetically favorable than the exocyclic one. PMID:19865516

Human breast tissue disposition and bioactivity of limonene in women with early-stage breast cancer.

Science.gov (United States)

Miller, Jessica A; Lang, Julie E; Ley, Michele; Nagle, Ray; Hsu, Chiu-Hsieh; Thompson, Patricia A; Cordova, Catherine; Waer, Amy; Chow, H-H Sherry

2013-06-01

Limonene is a bioactive food component found in citrus peel oil that has shown chemopreventive and chemotherapeutic activities in preclinical studies. We conducted an open-label pilot clinical study to determine the human breast tissue disposition of limonene and its associated bioactivity. We recruited 43 women with newly diagnosed operable breast cancer electing to undergo surgical excision to take 2 grams of limonene daily for two to six weeks before surgery. Blood and breast tissue were collected to determine drug/metabolite concentrations and limonene-induced changes in systemic and tissue biomarkers of breast cancer risk or carcinogenesis. Limonene was found to preferentially concentrate in the breast tissue, reaching high tissue concentration (mean = 41.3 μg/g tissue), whereas the major active circulating metabolite, perillic acid, did not concentrate in the breast tissue. Limonene intervention resulted in a 22% reduction in cyclin D1 expression (P = 0.002) in tumor tissue but minimal changes in tissue Ki67 and cleaved caspase-3 expression. No significant changes in serum leptin, adiponectin, TGF-β1, insulin-like growth factor binding protein-3 (IGFBP-3), and interleukin-6 (IL-6) levels were observed following limonene intervention. There was a small but statistically significant postintervention increase in insulin-like growth factor I (IGF-I) levels. We conclude that limonene distributed extensively to human breast tissue and reduced breast tumor cyclin D1 expression that may lead to cell-cycle arrest and reduced cell proliferation. Furthermore, placebo-controlled clinical trials and translational research are warranted to establish limonene's role for breast cancer prevention or treatment.

Release behavior and stability of encapsulated D-limonene from emulsion-based edible films.

Science.gov (United States)

Marcuzzo, Eva; Debeaufort, Frédéric; Sensidoni, Alessandro; Tat, Lara; Beney, Laurent; Hambleton, Alicia; Peressini, Donatella; Voilley, Andrée

2012-12-12

Edible films may act as carriers of active molecules, such as flavors. This possibility confers to them the status of active packaging. Two different film-forming biopolymers, gluten and ι-carrageenans, have been compared. D-Limonene was added to the two film formulations, and its release kinetics from emulsion-based edible films was assessed with HS-SPME. Results obtained for edible films were compared with D-limonene released from the fatty matrix called Grindsted Barrier System 2000 (GBS). Comparing ι-carrageenans with gluten-emulsified film, the latter showed more interesting encapsulating properties: in fact, D-limonene was retained by gluten film during the process needed for film preparation, and it was released gradually during analysis time. D-Limonene did not show great affinity to ι-carrageenans film, maybe due to high aroma compound hydrophobicity. Carvone release from the three different matrices was also measured to verify the effect of oxygen barrier performances of edible films to prevent D-limonene oxidation. Further investigations were carried out by FT-IR and liquid permeability measurements. Gluten film seemed to better protect D-limonene from oxidation. Gluten-based edible films represent an interesting opportunity as active packaging: they could retain and release aroma compounds gradually, showing different mechanical and nutritional properties from those of lipid-based ingredients.

Limonene inhibits methamphetamine-induced locomotor activity via regulation of 5-HT neuronal function and dopamine release.

Science.gov (United States)

Yun, Jaesuk

2014-05-15

Methamphetamine is a psychomotor stimulant that produces hyperlocomotion in rodents. Limonene (a cyclic terpene from citrus essential oils) has been reported to induce sedative effects. In this study, we demonstrated that limonene administration significantly inhibited serotonin (5-hydroxytryptamine, 5-HT)-induced head twitch response in mice. In rats, pretreatment with limonene decreased hyperlocomotion induced by methamphetamine injection. In addition, limonene reversed the increase in dopamine levels in the nucleus accumbens of rats given methamphetamine. These results suggest that limonene may inhibit stimulant-induced behavioral changes via regulating dopamine levels and 5-HT receptor function. Copyright © 2013 Elsevier GmbH. All rights reserved.

Involvement of transient receptor potential A1 channel in algesic and analgesic actions of the organic compound limonene.

Science.gov (United States)

Kaimoto, T; Hatakeyama, Y; Takahashi, K; Imagawa, T; Tominaga, M; Ohta, T

2016-08-01

TRPA1 is a Ca-permeable nonselective cation channel expressed in sensory neurons and acts as a nocisensor. Recent reports show that some monoterpenes, a group of naturally occurring organic compounds, modulate TRP channel activity. Here, we report that limonene, being contained in citrus fruits and mushrooms, shows a unique bimodal action on TRPA1 channel. We examine the effects of limonene on sensory neurons from wild-type, TRPV1- and TRPA1-gene-deficient mice and on heterologously expressed channels in vitro. Molecular determinants were identified with using mutated channels. Cellular excitability is monitored with ratiometric Ca imaging. Nociceptive and analgesic actions of limonene are also examined in vivo. In wild-type mouse sensory neurons, limonene increased the intracellular Ca(2+) concentration ([Ca(2+) ]i ), which was inhibited by selective inhibitors of TRPA1 but not TRPV1. Limonene-responsive neurons highly corresponded to TRPA1 agonist-sensitive ones. Limonene failed to stimulate sensory neurons from the TRPA1 (-/-) mouse. Heterologously expressed mouse TRPA1 was activated by limonene. Intraplantar injection of limonene elicited acute pain, which was significantly less in TRPA1 (-/-) mice. Systemic administration of limonene reduced nociceptive behaviours evoked by H2 O2 . In both heterologously and endogenously expressed TRPA1, a low concentration of limonene significantly inhibited H2 O2 -induced TRPA1 activation. TRPA1 activation by limonene was abolished in H2 O2 -insensitive cysteine-mutated channels. Topically applied limonene stimulates TRPA1, resulting in elicitation of acute pain, but its systemic application inhibits nociception induced by oxidative stress. Because limonene is a safe compound, it may be utilized for pain control due to its inhibition of TRPA1 channels. What does this study add: Limonene, a monoterpene in essential oils of various plants, has been known for its antitumor and anti-inflammatory properties. However, molecular

Engineering the productivity of recombinant Escherichia coli for limonene formation from glycerol in minimal media.

Science.gov (United States)

Willrodt, Christian; David, Christian; Cornelissen, Sjef; Bühler, Bruno; Julsing, Mattijs K; Schmid, Andreas

2014-08-01

The efficiency and productivity of cellular biocatalysts play a key role in the industrial synthesis of fine and bulk chemicals. This study focuses on optimizing the synthesis of (S)-limonene from glycerol and glucose as carbon sources using recombinant Escherichia coli. The cyclic monoterpene limonene is extensively used in the fragrance, food, and cosmetic industries. Recently, limonene also gained interest as alternative jet fuel of biological origin. Key parameters that limit the (S)-limonene yield, related to genetics, physiology, and reaction engineering, were identified. The growth-dependent production of (S)-limonene was shown for the first time in minimal media. E. coli BL21 (DE3) was chosen as the preferred host strain, as it showed low acetate formation, fast growth, and high productivity. A two-liquid phase fed-batch fermentation with glucose as the sole carbon and energy source resulted in the formation of 700 mg L(org) (-1) (S)-limonene. Specific activities of 75 mU g(cdw) (-1) were reached, but decreased relatively quickly. The use of glycerol as a carbon source resulted in a prolonged growth and production phase (specific activities of ≥50 mU g(cdw) (-1) ) leading to a final (S)-limonene concentration of 2,700 mg L(org) (-1) . Although geranyl diphosphate (GPP) synthase had a low solubility, its availability appeared not to limit (S)-limonene formation in vivo under the conditions investigated. GPP rerouting towards endogenous farnesyl diphosphate (FPP) formation also did not limit (S)-limonene production. The two-liquid phase fed-batch setup led to the highest monoterpene concentration obtained with a recombinant microbial biocatalyst to date. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Oxidized limonene and oxidized linalool - Concomitant contact allergy to common fragrance terpenes

DEFF Research Database (Denmark)

Bråred Christensson, Johanna; Karlberg, Ann Therese; Andersen, Klaus E.

2016-01-01

Summary Background Limonene and linalool are common fragrance terpenes. Both oxidized R-limonene and oxidized linalool have recently been patch tested in an international setting, showing contact allergy in 5.2% and 6.9% of dermatitis patients, respectively. Objective To investigate concomitant r...

Effects of nisin on the antimicrobial activity of d-limonene and its nanoemulsion.

Science.gov (United States)

Zhang, Zijie; Vriesekoop, Frank; Yuan, Qipeng; Liang, Hao

2014-05-01

d-Limonene has been considered to be a safer alternative compared to synthetic antimicrobial food additives. However, its hydrophobic and oxidative nature has limited its application in foods. The purpose of this research was to study effects of nisin on the antimicrobial activity of d-limonene and its nanoemulsion and develop a novel antimicrobial delivery system by combining the positive effect of these two antibacterial agents at the same time. By the checkerboard method, both the synergistic and additive effects of d-limonene and nisin were found against four selected food-related microorganisms. Then, d-limonene nanoemulsion with or without nisin was prepared by catastrophic phase inversion method, which has shown good droplet size and stability. The positive effects and outstanding antimicrobial activity of d-limonene nanoemulsion with nisin were confirmed by MICs comparison, scanning electron microscopy and determination of cell constituents released. Overall, the research described in the current article would be helpful in developing a more effective antimicrobial system for the production and preservation of foods. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

Functional and Structural Characterization of a (+)-Limonene Synthase from Citrus sinensis.

Science.gov (United States)

Morehouse, Benjamin R; Kumar, Ramasamy P; Matos, Jason O; Olsen, Sarah Naomi; Entova, Sonya; Oprian, Daniel D

2017-03-28

Terpenes make up the largest and most diverse class of natural compounds and have important commercial and medical applications. Limonene is a cyclic monoterpene (C 10 ) present in nature as two enantiomers, (+) and (-), which are produced by different enzymes. The mechanism of production of the (-)-enantiomer has been studied in great detail, but to understand how enantiomeric selectivity is achieved in this class of enzymes, it is important to develop a thorough biochemical description of enzymes that generate (+)-limonene, as well. Here we report the first cloning and biochemical characterization of a (+)-limonene synthase from navel orange (Citrus sinensis). The enzyme obeys classical Michaelis-Menten kinetics and produces exclusively the (+)-enantiomer. We have determined the crystal structure of the apoprotein in an "open" conformation at 2.3 Å resolution. Comparison with the structure of (-)-limonene synthase (Mentha spicata), which is representative of a fully closed conformation (Protein Data Bank entry 2ONG ), reveals that the short H-α1 helix moves nearly 5 Å inward upon substrate binding, and a conserved Tyr flips to point its hydroxyl group into the active site.

Direct suppression of a rice bacterial blight (Xanthomonas oryzae pv. oryzae) by monoterpene (S)-limonene.

Science.gov (United States)

Lee, Gun Woong; Chung, Moon-Soo; Kang, Mihyung; Chung, Byung Yeoup; Lee, Sungbeom

2016-05-01

Rice bacterial blight, caused by Xanthomonas oryzae pv. oryzae (Xoo), is a severe disease of rice plants. Upon pathogen infection, rice biosynthesizes phytoalexins, including diterpenoids such as momilactones, phytocassanes, and oryzalexins. However, information on headspace volatiles in response to Xoo infection is limited. We have examined headspace volatile terpenes, induced by the infection of Xoo, and investigated their biological roles in the rice plant. Monoterpenes α-thujene, α-pinene, sabinene, myrcene, α-terpene, and (S)-limonene and sesquiterpenes cyclosativene, α-copaene, and β-elemene were detected from 1-week-old Xoo-infected rice seedlings, by solid-phase microextraction-gas chromatography-mass spectrometry. All monoterpenes were constitutively released from rice seedlings before Xoo infection. However, (S)-limonene emission was further elicited after exposure of the seedlings to Xoo in coincidence with upregulation of limonene synthase gene (OsTPS20) transcripts. Only the stereospecific (S)-limonene [and not (R)-limonene or other monoterpenes] severely inhibited Xoo growth, as confirmed by disc diffusion and liquid culture assays. Rice seedlings showed suppressed pathogenic symptoms suggestive of resistance to Xoo infection after foliar treatment with (S)-limonene. Collectively, our findings suggest that (S)-limonene is a volatile phytoanticipin, which plays a significant role in suppressing Xoo growth in rice seedlings.

Ternary and quaternary (liquid + liquid) equilibria for (water + ethanol + α-pinene, +β-pinene, or +limonene) and (water + ethanol + α-pinene + limonene) at the temperature 298.15 K

International Nuclear Information System (INIS)

Li Hengde; Tamura, Kazuhiro

2006-01-01

(Liquid + liquid) equilibria and tie-lines for the ternary (water + ethanol + α-pinene, or β-pinene or limonene) and quaternary (water + ethanol + α-pinene + limonene) mixtures have been measured at T = 298.15 K. The experimental multicomponent (liquid + liquid) equilibrium data have been successfully represented in terms of the modified UNIQUAC model with binary parameters

Oxidation of limonene using activated carbon modified in dielectric barrier discharge plasma

Science.gov (United States)

Glonek, Karolina; Wróblewska, Agnieszka; Makuch, Edyta; Ulejczyk, Bogdan; Krawczyk, Krzysztof; Wróbel, Rafał. J.; Koren, Zvi C.; Michalkiewicz, Beata

2017-10-01

The waste from industrial fruits processing is utilized for the extraction of limonene, a renewable terpene biomass compound obtained from orange peels. This was followed by limonene oxidation, which produces highly useful oxygenated derivatives (carveol, and perillyl alcohol, 1,2-epoxylimonene and its diol). New catalysts were obtained by treating relatively inexpensive commercially available EuroPh and FPV activated carbons with plasma. These catalysts were characterized by the following instrumental methods XRD, sorption of N2 and CO2, SEM, EDS, TEM, XPS, and Raman spectroscopy. The activities of the plasma-treated catalysts were measured in the oxidation of limonene by means of either hydrogen peroxide or t-butyl hydroperoxide as the oxidizing agents. During the oxidation with hydrogen peroxide the new plasma-treated catalysts were more active than their untreated counterparts. This effect was noticeable in the considerable increase in the conversion of limonene. The mechanism explaining this property is proposed, and it takes into account the role of the appropriate functional groups on the surface of the catalysts. This work has shown for the first time that the commercial EuroPh and FPV activated carbons, after having been treated by plasma, are active catalysts for the selective limonene oxidation for the production of value-added industrial products.

Enhancing the antimicrobial activity of d-limonene nanoemulsion with the inclusion of ε-polylysine.

Science.gov (United States)

Zahi, Mohamed Reda; El Hattab, Mohamed; Liang, Hao; Yuan, Qipeng

2017-04-15

The objective of this research was to investigate the synergism between ε-polylysine and d-limonene and develop a novel nanoemulsion system by merging the positive effect of these two antimicrobial agents. Results from the checkerboard method showed that ε-polylysine and d-limonene exhibit strong synergistic and useful additive effects against Escherichia coli, Staphylococcus aureus, Bacillus subtilis and Saccharomyces cerevisiae. In addition, d-limonene nanoemulsion with the inclusion of ε-polylysine was successfully prepared by high pressure homogenizer technology. Its antimicrobial efficiency was compared with pure d-limonene nanoemulsion by measuring the minimal inhibitory concentration, electronic microscope observation and the leakage of the intercellular constituents. The results demonstrated a wide improvement of the antimicrobial activity of d-limonene nanoemulsion following the inclusion of ε-polylysine. Overall, the current study may have a valuable contribution to make in developing a more efficient antimicrobial system in the food industry. Copyright © 2016 Elsevier Ltd. All rights reserved.

Human breast tissue disposition and bioactivity of limonene in women with early stage breast cancer

Science.gov (United States)

Miller, Jessica A.; Lang, Julie E.; Ley, Michele; Nagle, Ray; Hsu, Chiu-Hsieh; Thompson, Patricia A; Cordova, Catherine; Waer, Amy; Chow, H.-H. Sherry

2013-01-01

Limonene is a bioactive food component found in citrus peel oil that has demonstrated chemopreventive and chemotherapeutic activities in preclinical studies. We conducted an open label pilot clinical study to determine the human breast tissue disposition of limonene and its associated bioactivity. We recruited forty-three women with newly diagnosed operable breast cancer electing to undergo surgical excision to take 2 grams of limonene daily for 2 – 6 weeks before surgery. Blood and breast tissue were collected to determine drug/metabolite concentrations and limonene-induced changes in systemic and tissue biomarkers of breast cancer risk or carcinogenesis. Limonene was found to preferentially concentrate in the breast tissue, reaching high tissue concentration (mean=41.3 μg/g tissue) while the major active circulating metabolite, perillic acid, did not concentrate in the breast tissue. Limonene intervention resulted in a 22% reduction in cyclin D1 expression (P=0.002) in tumor tissue but minimal changes in tissue Ki67 and cleaved caspase 3 expression. No significant changes in serum leptin, adiponectin, TGF-β1, IGFBP-3 and IL-6 levels were observed following limonene intervention. There was a small but statistically significant post-intervention increase in IGF-1 levels. We conclude that limonene distributed extensively to human breast tissue and reduced breast tumor cyclin D1 expression that may lead to cell cycle arrest and reduced cell proliferation. Further placebo-controlled clinical trials and translational research are warranted to establish limonene’s role for breast cancer prevention or treatment. PMID:23554130

Limonene in exhaled breath is elevated in hepatic encephalopathy

Science.gov (United States)

O’Hara, M E; Fernández del Río, R; Holt, A; Pemberton, P; Shah, T; Whitehouse, T; Mayhew, C A

2016-01-01

Abstract Breath samples were taken from 31 patients with liver disease and 30 controls in a clinical setting and proton transfer reaction quadrupole mass spectrometry (PTR-Quad-MS) used to measure the concentration of volatile organic compounds (VOCs). All patients had cirrhosis of various etiologies, with some also suffering from hepatocellular cancer (HCC) and/or hepatic encephalopathy (HE). Breath limonene was higher in patients with No-HCC than with HCC, median (lower/upper quartile) 14.2 (7.2/60.1) versus 3.6 (2.0/13.7) and 1.5 (1.1/2.3) nmol mol−1 in controls. This may reflect disease severity, as those with No-HCC had significantly higher UKELD (United Kingdom model for End stage Liver Disease) scores. Patients with HE were categorized as having HE symptoms presently, having a history but no current symptoms and having neither history nor current symptoms. Breath limonene in these groups was median (lower/upper quartile) 46.0 (14.0/103), 4.2 (2.6/6.4) and 7.2 (2.0/19.1) nmol mol−1, respectively. The higher concentration of limonene in those with current symptoms of HE than with a history but no current symptoms cannot be explained by disease severity as their UKELD scores were not significantly different. Longitudinal data from two patients admitted to hospital with HE show a large intra-subject variation in breath limonene, median (range) 18 (10–44) and 42 (32–58) nmol mol−1. PMID:27869108

Epoxidation of natural limonene extracted from orange peels with hydrogen peroxide over Ti-MCM-41 catalyst

Directory of Open Access Journals (Sweden)

Wróblewska Agnieszka

2018-03-01

Full Text Available The paper presents the oxidation of natural limonene (extracted from waste orange peels by 60 wt% hydrogen peroxide, in the presence of Ti-MCM-41 catalyst and in methanol as the solvent. The aim of the research was to develop the most favorable technological parameters for the process of limonene oxidation (temperature, molar ratio of limonene to hydrogen peroxide, methanol concentration, Ti-MCM-41 catalyst content and reaction time by analyzing changes in the main functions describing this process: the conversion of limonene, selectivities of appropriate products, the conversion of hydrogen peroxide and the effective conversion of hydrogen peroxide. The process is environmentally friendly process and it uses renewable raw material - limonene and a safe oxidant -hydrogen peroxide. During the study, very valuable oxygenated derivatives of limonene were obtained: 1,2-epoxylimonene, its diol, carvone, carveol, and perillyl alcohol. These compounds are used in medicine, cosmetics, perfumery, food and polymers industries.

Comparison of antispasmodic effects of Dracocephalum kotschyi essential oil, limonene and α-terpineol.

Science.gov (United States)

Sadraei, H; Asghari, G; Kasiri, F

2015-01-01

Dracocephalum kotschyi is an essential oil containing plant found in Iran. In Iranian traditional medicine, D. kotschyi has been used as antispasmodic and analgesic but so far there is no pharmacological report about its antispasmodic activity. Therefore, the objective of this research was to study antispasmodic activity of the essential oil of D. kotschyi and two of its constituents namely limonene and α-terpineol. The essential oil was obtained from aerial parts of D. kotschyi using hydrodistillation method. The main components found in the essential oil were α-pinene (10%), neral (11%), geraniol (10%), α-citral (12%), limonene (9%) and α-terpineol (1.1%). For antispasmodic studies, a portion of rat ileum was suspended under 1 g tension in Tyrode's solution at 37 °C and gassed with O2. Effect of the D. kotschyi essential oil, limonene and α-terpineol were studied on ileum contractions induced by KCl (80 mM), acetylcholine (ACh, 500 nM) and electrical field stimulation (EFS). The essential oil, in a concentration dependent manner inhibited the response to KCl (IC50=51 ± 8.7 nl/ml), ACh (IC50=19 ± 2.7 nl/ml) and EFS (IC50=15 ± 0.5 nl/ml). Limonene and α-terpineol showed same pattern of inhibitory effect on ileum contraction. Their inhibitory effects were also concentration dependent. However, limonene was more potent than the essential oil while the α-terpineol was less potent than either limonene or the essential oil. From this experiment it was concluded that D. kotschyi essential oil has inhibitory effect on ileum contractions. Limonene contribute a major role in inhibitory effect of the essential oil while α-terpineol has weak antispasmodic activity.

Investigation of interaction of phosphorotungstenvanadium heteropolyacids with sodium hydroxide by the methods of calorimetric and potentiometric titration

International Nuclear Information System (INIS)

Ganelina, E.Sh.; Borgoyakov, S.A.

1985-01-01

Interaction of phosphorotungstenvanadium heteropolyacids (HPA) with alkali (NaOH) is studied by the methods of calorimetric and potentiometric titration. Three stages are singled out: 1) neutralization of ''strong'' hydrogen atoms with a constant thermal effect of 52.0+-1.6 kJ/mol; 2) neutralization of ''weak'' protons, which acidity constant is of order 10 -2 ; 3) interaction of NaOH with hydrogen atoms combined with the internal sphere of HPA, and completed by HPA destruction. The data obtained are compared with the results, calculating the composition of polymer particles inside HPA, and they are discussed from the view point of their micellar structure

Monoterpene limonene induces brown fat-like phenotype in 3T3-L1 white adipocytes.

Science.gov (United States)

Lone, Jameel; Yun, Jong Won

2016-05-15

Several dietary compounds that are able to induce the brown fat-like phenotype in white adipocytes have been considered for treatment of obesity due to their ability to increase energy expenditure. Here, we report that limonene induces the brown fat-like phenotype in 3T3-L1 adipocytes by increasing expression of brown adipocyte-specific genes and proteins. Limonene-induced browning in white adipocytes was investigated by determining expression levels of brown fat-specific genes and proteins by real-time RT-PCR, immunoblot analysis, and immunocytochemical staining. Limonene enhanced mitochondrial biogenesis, as evidenced by increased mitochondrial content and immunofluorescent intensity. Limonene also significantly elevated protein levels of HSL, PLIN, p-AMPK, p-ACC, ACO, COX4, CPT1, and CYT C, suggesting its possible role in enhancement of lipolysis and lipid catabolism. Increased expression of PRDM16, UCP1, C/EBPβ, and other brown fat-specific markers by limonene was possibly mediated by activation of β3-adnergenic receptor (β3-AR), as inhibition of β3-AR inhibited up-regulation of brown fat-specific markers. Similarly, limonene-mediated activation of ERK and up-regulation of key brown adipocyte specific markers were eliminated by treatment with ERK antagonist. Taken together, these results suggest that limonene induces browning of 3T3-L1 adipocytes via activation of β3-AR and the ERK signaling pathway. In conclusion, our findings suggest that limonene plays a dual modulatory role in induction of the brown adipocyte-like phenotype as well as promotion of lipid metabolism and thus may have potential therapeutic implications for treatment of obesity. Copyright © 2016 Elsevier Inc. All rights reserved.

Synthesis of hydroxy derivatives of limonene

International Nuclear Information System (INIS)

Ardashov, O V; Volcho, K P; Salakhutdinov, N F

2014-01-01

Synthetic routes to mono-, di- and trihydroxy derivatives of limonene are presented. Emphasis is given to the problems of regio- and stereoselectivity of transformations. Data on the isolation from natural sources and on the biological activities of the title compounds are given. The bibliography includes 107 references

Solvent Free Preparation of p-Cymene from Limonene Using Vietnamese Montmorillonite

DEFF Research Database (Denmark)

Nguyen, Thao-Tran Thi; Duus, Fritz; Le, Thach Ngoc

2013-01-01

p-Cymene, an important intermediate in industrial chemistry, has been prepared in good yields by thermally induced dehydrogenation of limonene under solvent-free reaction conditions using Vietnamese montmorillonite as an efficient green catalyst.......p-Cymene, an important intermediate in industrial chemistry, has been prepared in good yields by thermally induced dehydrogenation of limonene under solvent-free reaction conditions using Vietnamese montmorillonite as an efficient green catalyst....

Effect of limonene on the heterotrophic growth and polyhydroxybutyrate production by Cupriavidus necator H16.

Science.gov (United States)

Guzman Lagunes, F; Winterburn, J B

2016-12-01

The inhibitory effect of limonene on polyhydroxybutyrate (PHB) production in Cupriavidus necator H16 was studied. Firstly, results demonstrate the feasibility of using orange juicing waste (OJW) as a substrate for PHB production. An intracellular PHB content of 81.4% (w/w) was attained for a total dry matter concentration of 9.58gL -1 , when the OJW medium was used. Later, a mineral medium designed to mimic the nutrient levels found in the complex medium derived from OJW was used to study the effect of limonene on the production of PHB. Results showed a drop in specific growth rate (μ) of more than 50% when the initial limonene concentration was 2% (v/v) compared to the limonene free medium. This work highlights the importance of a limonene recovery stage prior to fermentation, to maintain levels below 1% (v/v) in the medium, adding value to the OJW and enhancing the fermentation process productivity. Copyright © 2016 Elsevier Ltd. All rights reserved.

Characterization of the limonene oxidation products with liquid chromatography coupled to the tandem mass spectrometry

Science.gov (United States)

Witkowski, Bartłomiej; Gierczak, Tomasz

2017-04-01

Composition of the secondary organic aerosol (SOA) generated during ozonolysis of limonene was investigated with liquid chromatography coupled to the negative electrospray ionization (ESI), quadrupole tandem mass spectrometry (MS/MS) as well as high resolution Time-of-Flight mass spectrometry. Aerosol was generated in the flow-tube reactor. HR-MS/MS analysis allowed for proposing structures for the several up-to-date unknown limonene oxidation products. In addition to the low MW limonene oxidation products, significant quantities of oligomers characterized by elemental compositions: C19H30O5, C18H28O6, C19H28O7, C19H30O7 and C20H34O9 were detected in the SOA samples. It was concluded that these compounds are most likely esters, aldol reaction products and/or hemiacetals. In addition to detailed study of the limonene oxidation products, the reaction time as well as initial ozone concentration impact on the limonene SOA composition was investigated. The relative intensities of the two esters of the limonic acid and 7-hydroxy limononic acid increased as a result of lowering the initial ozone concentration and shortening the reaction time, indicating that esterification may be an important oligomerization pathway during limonene SOA formation.

Tunable d-Limonene Permeability in Starch-Based Nanocomposite Films Reinforced by Cellulose Nanocrystals.

Science.gov (United States)

Liu, Siyuan; Li, Xiaoxi; Chen, Ling; Li, Lin; Li, Bing; Zhu, Jie

2018-01-31

In order to control d-limonene permeability, cellulose nanocrystals (CNC) were used to regulate starch-based film multiscale structures. The effect of sphere-like cellulose nanocrystal (CS) and rod-like cellulose nanocrystal (CR) on starch molecular interaction, short-range molecular conformation, crystalline structure, and micro-ordered aggregated region structure were systematically discussed. CNC aspect ratio and content were proved to be independent variables to control d-limonene permeability via film-structure regulation. New hydrogen bonding formation and increased hydroxypropyl starch (HPS) relative crystallinity could be the reason for the lower d-limonene permeability compared with tortuous path model approximation. More hydrogen bonding formation, higher HPS relative crystallinity and larger size of micro-ordered aggregated region in CS0.5 and CR2 could explain the lower d-limonene permeability than CS2 and CR0.5, respectively. This study provided new insight for the control of the flavor release from starch-based films, which favored its application in biodegradable food packaging and flavor encapsulation.

Converting S-limonene synthase to pinene or phellandrene synthases reveals the plasticity of the active site.

Science.gov (United States)

Xu, Jinkun; Ai, Ying; Wang, Jianhui; Xu, Jingwei; Zhang, Yongkang; Yang, Dong

2017-05-01

S-limonene synthase is a model monoterpene synthase that cyclizes geranyl pyrophosphate (GPP) to form S-limonene. It is a relatively specific enzyme as the majority of its products are composed of limonene. In this study, we converted it to pinene or phellandrene synthases after introducing N345A/L423A/S454A or N345I mutations. Further studies on N345 suggest the polarity of this residue plays a critical role in limonene production by stabilizing the terpinyl cation intermediate. If it is mutated to a non-polar residue, further cyclization or hydride shifts occurs so the carbocation migrates towards the pyrophosphate, leading to the production of pinene or phellandrene. On the other hand, mutant enzymes that still possess a polar residue at this position produce limonene as the major product. N345 is not the only polar residue that may stabilize the terpinyl cation because it is not strictly conserved among limonene synthases across species and there are also several other polar residues in this area. These residues could form a "polar pocket" that may collectively play this stabilizing role. Our study provides important insights into the catalytic mechanism of limonene synthases. Furthermore, it also has wider implications on the evolution of terpene synthases. Copyright © 2017 Elsevier Ltd. All rights reserved.

[Advances in metabolic engineering for the microbial production of naturally occurring terpenes-limonene and bisabolene: a mini review].

Science.gov (United States)

Pang, Yaru; Hu, Zhihui; Xiao, Dongguang; Yu, Aiqun

2018-01-25

Limonene (C₁₀H₁₆) and bisabolene (C₁₅H₂₄) are both naturally occurring terpenes in plants. Depending on the number of C₅ units, limonene and bisabolene are recognized as representative monoterpenes and sesquiterpenes, respectively. Limonene and bisabolene are important pharmaceutical and nutraceutical products used in the prevention and treatment of cancer and many other diseases. In addition, they can be used as starting materials to produce a range of commercially valuable products, such as pharmaceuticals, nutraceuticals, cosmetics, and biofuels. The low abundance or yield of limonene and bisabolene in plants renders their isolation from plant sources non-economically viable. Isolation of limonene and bisabolene from plants also suffers from low efficiency and often requires harsh reaction conditions, prolonged reaction times, and expensive equipment cost. Recently, the rapid developments in metabolic engineering of microbes provide a promising alternative route for producing these plant natural products. Therefore, producing limonene and bisabolene by engineering microbial cells into microbial factories is becoming an attractive alternative approach that can overcome the bottlenecks, making it more sustainable, environmentally friendly and economically competitive. Here, we reviewed the status of metabolic engineering of microbes that produce limonene and bisabolene including microbial hosts, key enzymes, metabolic pathways and engineering of limonene/bisabolene biosynthesis. Furthermore, key challenges and future perspectives were discussed.

Bio-derived polymers for coating applications : comparing poly(limonene carbonate) and poly(cyclohexadiene carbonate)

NARCIS (Netherlands)

Stößer, T.; Li, C.; Unruangsri, J.; Saini, P.K.; Sablong, R.J.; Meier, M.A.R..; Williams, C.K.; Koning, C.

2017-01-01

Two fully bio-based polycarbonates, poly(cyclohexadiene carbonate) (PCHDC) and poly(limonene carbonate) (PLC), are synthesised from carbon dioxide and cyclohexadiene oxide and limonene oxide. The low molecular weight polycarbonates are cross-linked by a photoinitiated reaction with

Degradation of indoor limonene by outdoor ozone: A cascade of secondary organic aerosols.

Science.gov (United States)

Rösch, Carolin; Wissenbach, Dirk K; Franck, Ulrich; Wendisch, Manfred; Schlink, Uwe

2017-07-01

In indoor air, terpene-ozone reactions can form secondary organic aerosols (SOA) in a transient process. 'Real world' measurements conducted in a furnished room without air conditioning were modelled involving the indoor background of airborne particulate matter, outdoor ozone infiltrated by natural ventilation, repeated transient limonene evaporations, and different subsequent ventilation regimes. For the given setup, we disentangled the development of nucleated, coagulated, and condensed SOA fractions in the indoor air and calculated the time dependence of the aerosol mass fraction (AMF) by means of a process model. The AMF varied significantly between 0.3 and 5.0 and was influenced by the ozone limonene ratio and the background particles which existed prior to SOA formation. Both influencing factors determine whether nucleation or adsorption processes are preferred; condensation is strongly intensified by particulate background. The results provide evidence that SOA levels in natural indoor environments can surpass those known from chamber measurements. An indicator for the SOA forming potential of limonene was found to be limona ketone. Multiplying its concentration (in μg/m 3 ) by 450(±100) provides an estimate of the concentration of the reacted limonene. This can be used to detect a high particle formation potential due to limonene pollution, e.g. in epidemiological studies considering adverse health effects of indoor air pollutants. Copyright © 2017 Elsevier Ltd. All rights reserved.

Performance of semi-continuous membrane bioreactor in biogas production from toxic feedstock containing D-Limonene.

Science.gov (United States)

Wikandari, Rachma; Youngsukkasem, Supansa; Millati, Ria; Taherzadeh, Mohammad J

2014-10-01

A novel membrane bioreactor configuration containing both free and encased cells in a single reactor was proposed in this work. The reactor consisted of 120g/L of free cells and 120g/L of encased cells in a polyvinylidene fluoride membrane. Microcrystalline cellulose (Avicel) and d-Limonene were used as the models of substrate and inhibitor for biogas production, respectively. Different concentrations of d-Limonene i.e., 1, 5, and 10g/L were tested, and an experiment without the addition of d-Limonene was prepared as control. The digestion was performed in a semi-continuous thermophilic reactor for 75 days. The result showed that daily methane production in the reactor with the addition of 1g/L d-Limonene was similar to that of control. A lag phase was observed in the presence of 5g/L d-Limonene; however, after 10 days, the methane production increased and reached a similar production to that of the control after 15 days. Copyright © 2014 Elsevier Ltd. All rights reserved.

Physical stability of R-(+)-Limonene emulsions stabilized by Ulva fasciata algae polysaccharide.

Science.gov (United States)

Shao, Ping; Ma, Huiling; Qiu, Qiang; Jing, Weiping

2016-11-01

The physical stability of R-(+)-Limonene emulsions stabilized by Ulva fasciata polysaccharide (UFP) was investigated in this study. Emulsion physical stability was evaluated under different polysaccharide concentrations (1%-5%, wt/wt) and pH values (3.0-11.0). The stability of R-(+)-Limonene emulsions was demonstrated by droplet size distribution, rheological properties, zeta potential and visual phase separation. R-(+)-Limonene emulsions displayed monomodal droplet size distributions, high absolute values of zeta potential and good storage stability when 3% (wt/wt) UFP was used. The rheological properties and stability of R-(+)-Limonene emulsions appeared to be dependent on polysaccharide concentration. The emulsion stability was impacted by pH. Higher zeta potential (-52.6mV) and smaller mean droplet diameter (2.45μm) were achieved in neutral liquid environment (pH 7.0). Extreme acidity caused the flocculation of emulsions, which was manifested as phase separation, while emulsions were quite stable in an alkaline environment. Through comparing the stabilities of emulsions stabilized by different emulsifiers (i.e. UFP, GA and Gelatin), the result suggested that UFP was the best emulsifying agent among them. Copyright © 2016 Elsevier B.V. All rights reserved.

Limonene protects osteoblasts against methylglyoxal-derived adduct formation by regulating glyoxalase, oxidative stress, and mitochondrial function.

Science.gov (United States)

Suh, Kwang Sik; Chon, Suk; Choi, Eun Mi

2017-12-25

Methylglyoxal (MG) is a potent protein glycating agent and an important precursor of advanced glycation end products, which are involved in the pathogenesis of diabetic osteopathy. In this study, we investigated the effects of limonene on MG-induced damage in osteoblastic MC3T3-E1 cells. Pretreating cells with limonene prevented MG-induced protein adduct formation, tumor necrosis factor alpha and interleukin-6 release, mitochondrial superoxide production, and cardiolipin peroxidation. In addition, limonene increased glyoxalase I activity, and glutathione and heme oxygenase-1 levels in the presence of MG. Pretreatment with limonene prior to MG exposure reduced MG-induced mitochondrial dysfunction by preventing mitochondrial membrane potential dissipation and adenosine triphosphate loss, and reduced the levels of adenosine monophosphate-activated protein kinase, peroxisome proliferator activated receptor γ coactivator 1α, and nitric oxide. These results demonstrate that limonene may prevent the development of diabetic osteopathy. Copyright © 2017 Elsevier B.V. All rights reserved.

Intrinsic chirality and prochirality at Air/R-(+)- and S-(-)-limonene interfaces: spectral signatures with interference chiral sum-frequency generation vibrational spectroscopy.

Science.gov (United States)

Fu, Li; Zhang, Yun; Wei, Zhe-Hao; Wang, Hong-Fei

2014-09-01

We report in this work detailed measurements of the chiral and achiral sum-frequency vibrational spectra in the C-H stretching vibration region (2800-3050 cm(-1)) of the air/liquid interfaces of R-(+)-limonene and S-(-)-limonene, using the recently developed high-resolution broadband sum-frequency generation vibrational spectroscopy (HR-BB-SFG-VS). The achiral SFG spectra of R-limonene and S-limonene, as well as the RS racemic mixture (50/50 equal amount mixture), show that the corresponding molecular groups of the R and S enantiomers are with the same interfacial orientations. The interference chiral SFG spectra of the limonene enantiomers exhibit a spectral signature from the chiral response of the Cα-H stretching mode, and a spectral signature from the prochiral response of the CH(2) asymmetric stretching mode, respectively. The chiral spectral feature of the Cα-H stretching mode changes sign from R-(+)-limonene to S-(-)-limonene surfaces, and disappears for the RS racemic mixture surface. While the prochiral spectral feature of the CH(2) asymmetric stretching mode is the same for R-(+)-limonene and S-(-)-limonene surfaces, and also surprisingly remains the same for the RS racemic mixture surface. Therefore, the structures of the R-(+)-limonene and the S-(-)-limonene at the liquid interfaces are nevertheless not mirror images to each other, even though the corresponding groups have the same tilt angle from the interfacial normal, i.e., the R-(+)-limonene and the S-(-)-limonene at the surface are diastereomeric instead of enantiomeric. These results provide detailed information in understanding the structure and chirality of molecular interfaces and demonstrate the sensitivity and potential of SFG-VS as a unique spectroscopic tool for chirality characterization and chiral recognition at the molecular interface. © 2014 Wiley Periodicals, Inc.

High performance thiol-ene thermosets based on fully bio-based poly(limonene carbonate)s

NARCIS (Netherlands)

Li, C.; Johansson, M.; Sablong, R.J.; Koning, C.E.

2017-01-01

High glass transition temperature (Tg) thiol-ene networks (TENs) based on poly(limonene carbonate)s (PLCs), derived from orange oils and of potential degradability are described here. PLCs with moderate molecular weight were prepared by copolymerization of limonene oxide with CO2 and subsequent

The study of catalytic properties and phase composition of pyrolysis products of molybdophosphoric heteropolyacid. Communication 3. Environmental effect on the HPA pyrolysis

International Nuclear Information System (INIS)

Bondareva, V.M.; Andrushkevich, T.V.; Maksimovskaya, R.I.; Plyasova, L.M.; Litvak, G.S.; Burgina, E.B.

1997-01-01

Character of pyrolysis of molybdophosphonic heteropolyacid (HPA) (H 3 PMo 12 O 40 x13H 2 O) in different media (air, hydrogen, oxygen, helium, water vapour, as well reactive mixture containing acrolein) is studied within the temperature range of 200-700 deg C. With application of methods of X-ray analysis in situ, NMR 31 R and IR-spectroscopy it is shown that phase formation by HPA pyrolysis depends on the media, oxidation-reduction properties and availability of water vapour therein. 27 refs.; 5 figs

Synergistic inhibitory effect of berberine and d-limonene on human gastric carcinoma cell line MGC803.

Science.gov (United States)

Zhang, Xiu-Zhen; Wang, Ling; Liu, Dong-Wu; Tang, Guang-Yan; Zhang, Hong-Yu

2014-09-01

This study aims at evaluating the anticancer effects of berberine hydrochloride (berberine) and d-limonene, alone and in combination, on human gastric carcinoma cell line MGC803 to determine whether berberine and d-limonene work synergistically and elucidate their mechanisms. MGC803 cells were treated with berberine and d-limonene, alone and in combination, for 24-48 h. The inhibitory effects of these drugs on growth were determined by MTT assay. The combination index and drug reduction index were calculated with the Chou-Talalay method based on the median-effect principle. Flow cytometry and laser scanning confocal microscopy were employed to evaluate the effects of both drugs on cell-cycle perturbation and apoptosis, generation of reactive oxygen species (ROS), mitochondrial membrane potential, and expression of Bcl-2 and caspase-3 in MGC803 cells. Berberine or d-limonene alone can inhibit the growth of MGC803 cells in a dose- and time-dependent manner. Berberine and d-limonene at a combination ratio of 1:4 exhibited a synergistic effect on anti-MGC803 cells. The two drugs distinctly induced intracellular ROS generation, reduced the mitochondrial transmembrane potential (ΔΨm), enhanced the expression of caspase-3, and decreased the expression of Bcl-2. The combination of berberine and d-limonene showed more remarkable effects compared with drugs used singly in MGC803 cells. The combination of berberine and d-limonene exerted synergistic anticancer effects on MGC803 cells by cell-cycle arrest, ROS production, and apoptosis induction through the mitochondria-mediated intrinsic pathway.

Synthesis and physicochemical properties of Zr-MCM-41 mesoporous molecular sieves and Pt/H3PW12O40/Zr-MCM-41 catalysts

International Nuclear Information System (INIS)

Chen, L.F.; Wang, J.A.; Norena, L.E.; Aguilar, J.; Navarrete, J.; Salas, P.; Montoya, J.A.; Del Angel, P.

2007-01-01

For the first time, modifications of the surface and framework of Si-MCM-41 by depositing a heteropolyacid on the surface and by introducing foreign Zr 4+ ions into the framework are investigated. The Zr-modified Si-MCM-41 mesoporous materials (hereafter referred as WSZn, n=Si/Zr=25, 15, 8, 4) were synthesized through a surfactant-templated preparation approach, using low-cost fumed silica as the Si precursor. After impregnation with 25 wt% of H 3 PW 12 O 40 , the surface Broensted acidity of the Pt/H 3 PW 12 O 40 /WSZn catalysts was greatly enhanced by 2-10 times relative to the bare WSZn support. Two kinds of supported heteropolyacids were formed: (i) bulk-like heteropolyacid crystals with unchanged Keggin structures, and (ii) highly dispersed heteropolyacid with distorted Keggin units. The formation of various kinds of heteropolyacid structures is closely related to the interaction between the heteropolyanions and the hydroxyl groups in the host support. - Graphical abstract: Modifications of the surface and framework of Si-MCM-41 by depositing a heteropolyacid on the surface and by introducing foreign Zr 4+ ions into the framework are investigated. Broensted acidity of the Pt/H 3 PW 12 O 40 /Zr-MCM-41 catalysts was greatly enhanced by 2-10 times relative to the bare Zr-MCM-41 support

Molecular Modeling and Physicochemical Properties of Supramolecular Complexes of Limonene with α- and β-Cyclodextrins.

Science.gov (United States)

Dos Passos Menezes, Paula; Dos Santos, Polliana Barbosa Pereira; Dória, Grace Anne Azevedo; de Sousa, Bruna Maria Hipólito; Serafini, Mairim Russo; Nunes, Paula Santos; Quintans-Júnior, Lucindo José; de Matos, Iara Lisboa; Alves, Péricles Barreto; Bezerra, Daniel Pereira; Mendonça Júnior, Francisco Jaime Bezerra; da Silva, Gabriel Francisco; de Aquino, Thiago Mendonça; de Souza Bento, Edson; Scotti, Marcus Tullius; Scotti, Luciana; de Souza Araujo, Adriano Antunes

2017-02-01

This study evaluated three different methods for the formation of an inclusion complex between alpha- and beta-cyclodextrin (α- and β-CD) and limonene (LIM) with the goal of improving the physicochemical properties of limonene. The study samples were prepared through physical mixing (PM), paste complexation (PC), and slurry complexation (SC) methods in the molar ratio of 1:1 (cyclodextrin:limonene). The complexes prepared were evaluated with thermogravimetry/derivate thermogravimetry, infrared spectroscopy, X-ray diffraction, complexation efficiency through gas chromatography/mass spectrometry analyses, molecular modeling, and nuclear magnetic resonance. The results showed that the physical mixing procedure did not produce complexation, but the paste and slurry methods produced inclusion complexes, which demonstrated interactions outside of the cavity of the CDs. However, the paste obtained with β-cyclodextrin did not demonstrate complexation in the gas chromatographic technique because, after extraction, most of the limonene was either surface-adsorbed by β-cyclodextrin or volatilized during the procedure. We conclude that paste complexation and slurry complexation are effective and economic methods to improve the physicochemical character of limonene and could have important applications in pharmacological activities in terms of an increase in solubility.

PRODUKSI BIOGAS DARI SAMPAH BUAH DAN SAYUR : PENGARUH VOLATILE SOLID DAN LIMONEN

Directory of Open Access Journals (Sweden)

Piyantina Rukmini

2016-10-01

Full Text Available Abstrak- Biogas merupakan salah satu sumber energi alternatif yang sedang dikembangkan dan sumber energi yang terbarukan. Bahan baku yang digunakan adalah kulit jeruk busuk (Citrus sinensia osbeck dan kobis (Brassica oleracea. Penelitian ini bertujuan untuk mengetahui pengaruh volatile solid dan limonen terhadap produksi biogas. Penelitian menggunakan erlenmeyer 500 mL sebanyak 6 buah, waterbath, manometer air, dan thermometer. Volume total digester 350 mL. Penelitian dilakukan dengan cara menghancurkan bahan baku supaya lebih mudah didegradasi oleh bakteri. Oksigen yang bersifat toxic bagi bakteri anaerobik, dapat dihilangkan dengan penambahan N2 dalam digester pada awal operasi. Penelitian dilakukan pada kondisi mesofilik (30 – 400C selama 50 hari. Hasil penelitian menunjukkan bahwa pada digester yang memiliki VS sama (T1 dan T3 dengan 15% VS, dan T2 dan T4 dengan 20% VS, dengan konsentrasi kulit jeruk/limonen berbeda (T1= 114ppm< T3= 170ppm, dan T2= 152ppmlimonen yang lebih tinggi akan menghasilkan asam asetat lebih tinggi pada setiap minggunya. Akumulasi asam asetat pada fase acethogenesis menyebabkan bakteri methanogen tidak dapat tumbuh dengan optimum pada fase berikutnya (methanogenesis. Pada kondisi yang sama, digester yang memiliki konsentrasi kulit jeruk/limonen yang lebih besar (T1limonen 114ppm, diperoleh metana dengan kadar 0.1298%V/grVS

Oral administration of d-limonene controls inflammation in rat colitis and displays anti-inflammatory properties as diet supplementation in humans.

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d'Alessio, Patrizia A; Ostan, Rita; Bisson, Jean-François; Schulzke, Joerg D; Ursini, Matilde V; Béné, Marie C

2013-07-10

To further explore the anti-inflammatory properties of d-Limonene. A rat model was used to compare evolution of TNBS (2,5,6-trinitrobenzene sulfonic acid)-induced colitis after oral feeding with d-Limonene compared to ibuprofen. Peripheral levels of TNF-α (Tumor Necrosis Factor alpha) were assessed in all animals. Cell cultures of fibroblasts and enterocytes were used to test the effect of d-Limonene respectively on TNFα-induced NF-κB (nuclear factor-kappa B) translocation and epithelial resistance. Finally, plasmatic inflammatory markers were examined in an observational study of diet supplementation with d-Limonene-containing orange peel extract (OPE) in humans. Administered per os at a dose of 10mg/kg p.o., d-Limonene induced a significant reduction of intestinal inflammatory scores, comparable to that induced by ibuprofen. Moreover, d-Limonene-fed rats had significantly lowered serum concentrations of TNF-α compared to untreated TNBS-colitis rats. The anti-inflammatory effect of d-Limonene also involved inhibition of TNFα-induced NF-κB translocation in fibroblast cultures. The application of d-Limonene on colonic HT-29/B6 cell monolayers increased epithelial resistance. Finally, inflammatory markers, especially peripheral IL-6, markedly decreased upon OPE supplementation of elderly healthy subjects submitted or not to 56 days of dietary supplementation with OPE. In conclusion, d-Limonene indeed demonstrates significant anti-inflammatory effects both in vivo and in vitro. Protective effects on the epithelial barrier and decreased cytokines are involved, suggesting a beneficial role of d-Limonene as diet supplement in reducing inflammation. Copyright © 2013 Elsevier Inc. All rights reserved.

d-limonene ameliorates diabetes and its complications in streptozotocin-induced diabetic rats.

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Bacanlı, Merve; Anlar, Hatice Gül; Aydın, Sevtap; Çal, Tuğbagül; Arı, Nuray; Ündeğer Bucurgat, Ülkü; Başaran, A Ahmet; Başaran, Nurşen

2017-12-01

It is known that diabetes causes some complications including alterations in lipid profile, hepatic enzyme levels but also it causes oxidative stress. Limonene, a major component of Citrus oils, has important health beneficial effects in lowering the level of oxidative stress due to its antioxidant activity. The aim of this study was to investigate the effects of D-limonene on streptozotocin (STZ)-induced diabetes in Wistar albino rats. For this purpose, DNA damage was evaluated by alkaline comet assay. Changes in the activities of catalase (CAT), superoxide dismutase (SOD), glutathione reductase (GR) and glutathione peroxidase (GSHPx) and the levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG), total glutathione (GSH), malondialdehyde (MDA), insulin, total bilirubin and BCA protein, alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma-glutamyl transferase (GGT), high density lipoprotein (HDL), low density lipoprotein (LDL), total cholesterol and triglyceride were also evaluated. D-limonene treatment was found to significantly decrease DNA damage, GR enzyme activities and MDA levels and significantly increase GSH levels and CAT, SOD and GSH-Px enzyme activities and altered lipid and liver enzyme parameters in diabetic rats. According to our results, it seems that D-limonene might have a role in the prevention of the complication of diabetes in rats. Copyright © 2017 Elsevier Ltd. All rights reserved.

Inhibition of growth and metastasis of human gastric cancer implanted in nude mice by d-limonene

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Lu, Xiao-Guang; Zhan, Li-Bin; Feng, Bing-An; Qu, Ming-Yang; Yu, Li-Hua; Xie, Ji-Hong

2004-01-01

AIM: To investigate the effects and mechanism of d-limonene on the growth and metastasis of gastric cancer in vivo. METHODS: Metastatic model simulating human gastric cancer was established by orthotopic implantation of histologically intact human tumor tissue into gastric wall of nude mice. One percent d-limonene was orally administered at dose of 15 ml/kg every other day for seven weeks. Eight weeks after implantation, tumor weight, inhibition rate, apoptotic index (AI), microvessel density (MVD), vascular endothelial growth factor (VEGF), variation of ultrastructure, and the presence of metastasis were evaluated, respectively, after the mice were sacrificed. RESULTS: The tumor weight was significantly reduced in 5-FU group (2.55 ± 0.28 g), d-limonene group (1.49 ± 0.09 g) and combined treatment group (1.48 ± 0.21 g) compared with the control group(2.73 ± 0.23 g, P limonene group, combined treatment group, the inhibition rates were 2.60%, 47.58% and 46.84% and 0, respectively; AI was (3.31 ± 0.33)%, (8.26 ± 1.21)%, (20.99 ± 1.84)% and (19.34 ± 2.19)%, respectively; MVD was (8.64 ± 2.81), (16.77 ± 1.39), (5.32 ± 4.26) and (5.86 ± 2.27), respectively; VEGF expression was (45.77 ± 4.79), (41.34 ± 5.41), (29.71 ± 8.92) and (28.24 ± 8.55), respectively. The incidences of peritoneal metastasis also decreased significantly in 5-FU group(77.8%), d-limonene group (20.0%) and combined group (22.2%) compared with control group (100%) versus 62.5%, 30% and 22.2%) (P limonene group and combined group than that in control group (87.5% vs 55.5%, 20.0% and 22.2% respectively) (P limonene group and combined group was 25.0%, 22.2%, 0, 0, respectively and 12.5%, 11.1% 0, 0, with respect to the metastasis rate to other organs. CONCLUSION: d-limonene has antiangiogenic and proapoptotic effects on gastric cancer, thereby inhibits tumor growth and metastasis. Combination of d-limonene with cytotoxic agents may be more effective. PMID:15237454

Comparative study of the bioconversion process using R-(+)- and S-(-)-limonene as substrates for Fusarium oxysporum 152B.

Science.gov (United States)

Molina, Gustavo; Bution, Murillo L; Bicas, Juliano L; Dolder, Mary Anne Heidi; Pastore, Gláucia M

2015-05-01

This study compared the bioconversion process of S-(-)-limonene into limonene-1,2-diol with the already established biotransformation of R-(+)-limonene into α-terpineol using the same biocatalyst in both processes, Fusarium oxysporum 152B. The bioconversion of the S-(-)-isomer was tested on cell permeabilisation under anaerobic conditions and using a biphasic system. When submitted to permeabilisation trials, this biocatalyst has shown a relatively high resistance; still, no production of limonene-1,2-diol and a loss of activity of the biocatalyst were observed after intense cell treatment, indicating a complete loss of cell viability. Furthermore, the results showed that this process can be characterised as an aerobic system that was catalysed by limonene-1,2-epoxide hydrolase, had an intracellular nature and was cofactor-dependent because the final product was not detected by an anaerobic process. Finally, this is the first report to characterise the bioconversion of R-(+)- and S-(-)-limonene by cellular detoxification using ultra-structural analysis. Copyright © 2014 Elsevier Ltd. All rights reserved.

Intrinsic Chirality and Prochirality at Air/R-(+)- and S-(-)-Limonene Interfaces: Spectral Signatures with Interference Chiral Sum-Frequency Generation Vibrational Spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Fu, Li; Zhang, Yun; Wei, Zhehao; Wang, Hongfei

2014-06-04

We report in this work detailed measurements on the chiral and achiral sum-frequency vibrational spectra in the C-H stretching vibration region (2800-3050cm-1) of the air/liquid interfaces of R-limonene and S-limonene, using the recently developed high-resolution broadband sum-frequency generation vibrational spectroscopy (HR-BB-SFG-VS). The achiral SFG spectra of R-limonene and S-limonene, as well as the equal amount (50/50) racemic mixture show that the enantiomers are with the same interfacial orientations. The interference chiral SFG spectra of the limonene enantiomers exhibit spectral signature from chiral response of the Cα-H stretching mode, and spectral signature from prochiral response of the CH2 asymmetric stretching mode, respectively. The chiral spectral feature of the Cα-H stretching mode changes sign from R-limonene to S-limonene, and disappears for the 50/50 racemic mixture. While the prochiral spectral feature of the CH2 asymmetric stretching mode is the same for R-limonene and S-limonene, and also surprisingly remains the same for the 50/50 racemic mixture. These results provided detail information in understanding the structure and chirality of molecular interfaces, and demonstrated the sensitivity and potential of SFG-VS as unique spectroscopic tool for chirality characterization and chiral recognition at the molecular interface.

Photocatalysis of sub-ppm limonene over multiwalled carbon nanotubes/titania composite nanofiber under visible-light irradiation.

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Jo, Wan-Kuen; Kang, Hyun-Jung

2015-01-01

This study was conducted under visible-light exposure to investigate the photocatalytic characteristics of a multiwalled carbon nanotube/titania (TiO2) composite nanofiber (MTCN) using a continuous-flow tubular reactor. The MTCN was prepared by a sol-gel process, followed by an electrospinning technique. The photocatalytic decomposition efficiency for limonene on the MTCN was higher than those obtained from reference TiO2 nanofibers or P25 TiO2, and the experimental results agreed well with the Langmuir-Hinshelwood model. The CO concentrations generated during the photocatalysis did not reach levels toxic to humans. The mineralization efficiency for limonene on the MTCN was also higher than that for P25 TiO2. Moreover, the mineralization efficiency obtained using the MTCN increased steeply from 8.3 to 91.1% as the residence time increased from 7.8 to 78.0s, compared to the increase in the decomposition efficiencies for limonene from 90.1 to 99.9%. Three gas-phase intermediates (methacrolein, acetic acid, and limonene oxide) were quantitatively determined for the photocatalysis for limonene over the MTCN, whereas only two intermediates (acetic acid and limonene oxide) were quantitatively determined over P25 TiO2. Other provisional gas-phase intermediates included cyclopropyl methyl ketone and 2-ethylbutanal. Copyright © 2014 Elsevier B.V. All rights reserved.

Photocatalysis of sub-ppm limonene over multiwalled carbon nanotubes/titania composite nanofiber under visible-light irradiation

International Nuclear Information System (INIS)

Jo, Wan-Kuen; Kang, Hyun-Jung

2015-01-01

Highlights: • A multiwalled carbon nanotube/titania composite nanofiber (MTCN) was synthesized. • Photocatalytic function of visible-activated MTCN was examined using tubular reactor. • MTCNs could be effectively used for the purification of sub-ppm gas-phase limonene. • The experimental results agreed well with Langmuir–Hinshelwood model. • Certain gas-phase intermediates were determined, but not for adsorbed intermediates. - Abstract: This study was conducted under visible-light exposure to investigate the photocatalytic characteristics of a multiwalled carbon nanotube/titania (TiO 2 ) composite nanofiber (MTCN) using a continuous-flow tubular reactor. The MTCN was prepared by a sol–gel process, followed by an electrospinning technique. The photocatalytic decomposition efficiency for limonene on the MTCN was higher than those obtained from reference TiO 2 nanofibers or P25 TiO 2 , and the experimental results agreed well with the Langmuir–Hinshelwood model. The CO concentrations generated during the photocatalysis did not reach levels toxic to humans. The mineralization efficiency for limonene on the MTCN was also higher than that for P25 TiO 2 . Moreover, the mineralization efficiency obtained using the MTCN increased steeply from 8.3 to 91.1% as the residence time increased from 7.8 to 78.0 s, compared to the increase in the decomposition efficiencies for limonene from 90.1 to 99.9%. Three gas-phase intermediates (methacrolein, acetic acid, and limonene oxide) were quantitatively determined for the photocatalysis for limonene over the MTCN, whereas only two intermediates (acetic acid and limonene oxide) were quantitatively determined over P25 TiO 2 . Other provisional gas-phase intermediates included cyclopropyl methyl ketone and 2-ethylbutanal

Photocatalysis of sub-ppm limonene over multiwalled carbon nanotubes/titania composite nanofiber under visible-light irradiation

Energy Technology Data Exchange (ETDEWEB)

Jo, Wan-Kuen, E-mail: wkjo@knu.ac.kr; Kang, Hyun-Jung

2015-02-11

Highlights: • A multiwalled carbon nanotube/titania composite nanofiber (MTCN) was synthesized. • Photocatalytic function of visible-activated MTCN was examined using tubular reactor. • MTCNs could be effectively used for the purification of sub-ppm gas-phase limonene. • The experimental results agreed well with Langmuir–Hinshelwood model. • Certain gas-phase intermediates were determined, but not for adsorbed intermediates. - Abstract: This study was conducted under visible-light exposure to investigate the photocatalytic characteristics of a multiwalled carbon nanotube/titania (TiO{sub 2}) composite nanofiber (MTCN) using a continuous-flow tubular reactor. The MTCN was prepared by a sol–gel process, followed by an electrospinning technique. The photocatalytic decomposition efficiency for limonene on the MTCN was higher than those obtained from reference TiO{sub 2} nanofibers or P25 TiO{sub 2}, and the experimental results agreed well with the Langmuir–Hinshelwood model. The CO concentrations generated during the photocatalysis did not reach levels toxic to humans. The mineralization efficiency for limonene on the MTCN was also higher than that for P25 TiO{sub 2}. Moreover, the mineralization efficiency obtained using the MTCN increased steeply from 8.3 to 91.1% as the residence time increased from 7.8 to 78.0 s, compared to the increase in the decomposition efficiencies for limonene from 90.1 to 99.9%. Three gas-phase intermediates (methacrolein, acetic acid, and limonene oxide) were quantitatively determined for the photocatalysis for limonene over the MTCN, whereas only two intermediates (acetic acid and limonene oxide) were quantitatively determined over P25 TiO{sub 2}. Other provisional gas-phase intermediates included cyclopropyl methyl ketone and 2-ethylbutanal.

Decoupling production from growth by magnesium sulfate limitation boosts de novo limonene production.

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Willrodt, Christian; Hoschek, Anna; Bühler, Bruno; Schmid, Andreas; Julsing, Mattijs K

2016-06-01

The microbial production of isoprenoids has recently developed into a prime example for successful bottom-up synthetic biology or top-down systems biology strategies. Respective fermentation processes typically rely on growing recombinant microorganisms. However, the fermentative production of isoprenoids has to compete with cellular maintenance and growth for carbon and energy. Non-growing but metabolically active E. coli cells were evaluated in this study as alternative biocatalyst configurations to reduce energy and carbon loss towards biomass formation. The use of non-growing cells in an optimized fermentation medium resulted in more than fivefold increased specific limonene yields on cell dry weight and glucose, as compared to the traditional growing-cell-approach. Initially, the stability of the resting-cell activity was limited. This instability was overcome via the optimization of the minimal fermentation medium enabling high and stable limonene production rates for up to 8 h and a high specific yield of ≥50 mg limonene per gram cell dry weight. Omitting MgSO4 from the fermentation medium was very promising to prohibit growth and allow high productivities. Applying a MgSO4 -limitation also improved limonene formation by growing cells during non-exponential growth involving a reduced biomass yield on glucose and a fourfold increase in specific limonene yields on biomass as compared to non-limited cultures. The control of microbial growth via the medium composition was identified as a key but yet underrated strategy for efficient isoprenoid production. Biotechnol. Bioeng. 2016;113: 1305-1314. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

Resistance to pathogens in terpene down-regulated orange fruits inversely correlates with the accumulation of D-limonene in peel oil glands.

Science.gov (United States)

Rodríguez, Ana; Shimada, Takehiko; Cervera, Magdalena; Redondo, Ana; Alquézar, Berta; Rodrigo, María Jesús; Zacarías, Lorenzo; Palou, Lluís; López, María M; Peña, Leandro

2015-01-01

Volatile organic compounds (VOCs) are secondary metabolites acting as a language for the communication of plants with the environment. In orange fruits, the monoterpene D-limonene accumulates at very high levels in oil glands from the peel. Drastic down-regulation of D-limonene synthase gene expression in the peel of transgenic oranges harboring a D-limonene synthase transgene in antisense (AS) configuration altered the monoterpene profile in oil glands, mainly resulting in reduced accumulation of D-limonene. This led to fruit resistance against Penicillium digitatum (Pd), Xanthomonas citri subsp. citri (Xcc) and other specialized pathogens. Here, we analyze resistance to pathogens in independent AS and empty vector (EV) lines, which have low, medium or high D-limonene concentrations and show that the level of resistance is inversely related to the accumulation of D-limonene in orange peels, thus explaining the need of high D-limonene accumulation in mature oranges in nature for the efficient attraction of specialized microorganism frugivores.

Skin permeation of D-limonene-based nanoemulsions as a transdermal carrier prepared by ultrasonic emulsification.

Science.gov (United States)

Lu, Wen-Chien; Chiang, Been-Huang; Huang, Da-Wei; Li, Po-Hsien

2014-03-01

Nanoemulsions can be used for transporting pharmaceutical phytochemicals in skin-care products because of their stability and rapid permeation properties. However, droplet size may be a critical factor aiding permeation through skin and transdermal delivery efficiency. We prepared D-limonene nanoemulsions with various droplet sizes by ultrasonic emulsification using mixed surfactants of sorbitane trioleate and polyoxyethylene (20) oleyl ether under different hydrophilic-lipophilic balance (HLB) values. Droplet size decreased with increasing HLB value. With HLB 12, the droplet size was 23 nm, and the encapsulated ratio peaked at 92.3%. Transmission electron microscopy revealed spherical droplets and the gray parts were D-limonene precipitation incorporated in spherical droplets of the emulsion system. Franz diffusion cell was used to evaluate the permeation of D-limonene nanoemulsion through rat abdominal skin; the permeation rate depended on droplet size. The emulsion with the lowest droplet size (54 nm) achieved the maximum permeation rate. The concentration of D-limonene in the skin was 40.11 μL/cm(2) at the end of 360 min. Histopathology revealed no distinct voids or empty spaces in the epidermal region of permeated rat skin, so the D-limonene nanoemulsion may be a safe carrier for transdermal drug delivery. Copyright © 2013 Elsevier B.V. All rights reserved.

Identification of a novel oxygenase capable of regiospecific hydroxylation of D-limonene into (+)-trans-carveol

NARCIS (Netherlands)

Groeneveld, M.; van Beek, H. L.; Duetz, W. A.; Fraaije, M. W.

2016-01-01

By genome sequencing and analysis, we have been able to identify a gene cluster encoding a four component oxygenase which is able to oxidize D-limonene, L-limonene, cumene, and indole. Heterologous expression of the complete oxygenase system in Pseudomonas putida S12 allowed efficient and highly

Metabolic engineering of the pentose phosphate pathway for enhanced limonene production in the cyanobacterium Synechocysti s sp. PCC 6803.

Science.gov (United States)

Lin, Po-Cheng; Saha, Rajib; Zhang, Fuzhong; Pakrasi, Himadri B

2017-12-13

Isoprenoids are diverse natural compounds, which have various applications as pharmaceuticals, fragrances, and solvents. The low yield of isoprenoids in plants makes them difficult for cost-effective production, and chemical synthesis of complex isoprenoids is impractical. Microbial production of isoprenoids has been considered as a promising approach to increase the yield. In this study, we engineered the model cyanobacterium Synechocystis sp. PCC 6803 for sustainable production of a commercially valuable isoprenoid, limonene. Limonene synthases from the plants Mentha spicata and Citrus limon were expressed in cyanobacteria for limonene production. Production of limonene was two-fold higher with limonene synthase from M. spicata than that from C. limon. To enhance isoprenoid production, computational strain design was conducted by applying the OptForce strain design algorithm on Synechocystis 6803. Based on the metabolic interventions suggested by this algorithm, genes (ribose 5-phosphate isomerase and ribulose 5-phosphate 3-epimerase) in the pentose phosphate pathway were overexpressed, and a geranyl diphosphate synthase from the plant Abies grandis was expressed to optimize the limonene biosynthetic pathway. The optimized strain produced 6.7 mg/L of limonene, a 2.3-fold improvement in productivity. Thus, this study presents a feasible strategy to engineer cyanobacteria for photosynthetic production of isoprenoids.

Effects of limonene stress on the growth of and microcystin release by the freshwater cyanobacterium Microcystis aeruginosa FACHB-905.

Science.gov (United States)

Hu, Xi; Liu, Yunguo; Zeng, Guangming; Hu, Xinjiang; Wang, Yaqin; Zeng, Xiaoxia

2014-07-01

The effects of limonene exposure on the growth of Microcystisaeruginosa and the release of toxic intracellular microcystin (MCY) were tested by evaluating the results obtained from the batch culture experiments with M. aeruginosa FACHB-905. The time series of cell as well as intracellular and extracellular MCY concentrations were evaluated during 5d of the incubation. After exposure to limonene, the number of cells gradually diminished; the net log cell reduction after 5d of the exposure was 3.0, 3.6, and 3.8log when the initial cell densities were set at 1.6×10(7), 1.1×10(6) and 4.1×10(5)cell/mL, respectively. Limonene was found to significantly influence the production and release of MCY. As the limonene exposure could inhibit the increase in the number of cells, the increase in the total MCY concentration in the medium was also inhibited. In the presence of limonene, the intracellular MCY was gradually released into the medium through a gradual reduction in the number of cells. The extracellular MCY concentration in the medium was significantly higher in the limonene-exposed samples than in the control samples, which confirmed that limonene cannot decompose the extracellular MCY. Copyright © 2014 Elsevier Inc. All rights reserved.

Biotransformation of limonene by an endophytic fungus using synthetic and orange residue-based media.

Science.gov (United States)

Bier, Mário Cesar Jucoski; Medeiros, Adriane Bianchi Pedroni; Soccol, Carlos Ricardo

2017-02-01

Aroma and fragrances have high commercial value for use in food, cosmetics and perfumes. The biotransformation of terpenes by microorganisms represents an attractive alternative method for production of flavourings. Endophytic fungi offer a great potential for the production of several groups of compounds; however, few studies have evaluated the biotransformation of limonene. Following preliminary studies on the biotransformation of limonene, submerged fermentation was carried out using an endophytic fungus isolated from Pinus taeda and identified as Phomopsis sp. The presence of several biotransformation products was detected and identified by mass spectrometry (GC-MS). The studied strain showed a divergent metabolic behaviour, as compounds of interest such as α-terpineol, carvone, and limoneno-1,2-diol were produced under different conditions. In addition to the minor metabolites terpinen-4-ol, menthol and carveol, this strain also produced major metabolites, including 0.536 g L -1 carvone and 2.08 g L -1 limonene-1,2-diol in synthetic medium and 2.10 g L -1 limonene-1,2-diol in a natural orange extract medium with single fed-batch, while the cyclic fed-batch resulted in concentrations less than 1 g L -1 . Therefore, our study produced a wide variety of limonene derivatives at a high concentration using a natural medium and a newly isolated endophytic fungal strain. Copyright © 2016 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

Limonene ozonolysis in the presence of nitric oxide: Gas-phase reaction products and yields

Science.gov (United States)

Ham, Jason E.; Harrison, Joel C.; Jackson, Stephen R.; Wells, J. R.

2016-05-01

The reaction products from limonene ozonolysis were investigated using the new carbonyl derivatization agent, O-tert-butylhydroxylamine hydrochloride (TBOX). With ozone (O3) as the limiting reagent, five carbonyl compounds were detected. The yields of the carbonyl compounds are discussed with and without the presence of a hydroxyl radical (OHrad) scavenger, giving insight into the influence secondary OH radicals have on limonene ozonolysis products. The observed reaction product yields for limonaketone (LimaKet), 7-hydroxyl-6-oxo-3-(prop-1-en-2-yl)heptanal (7H6O), and 2-acetyl-5-oxohexanal (2A5O) were unchanged suggesting OHrad generated by the limonene + O3 reaction does not contribute to their formation. The molar yields of 3-isopropenyl-6-oxo-heptanal (IPOH) and 3-acetyl-6-oxoheptanal (3A6O) decreased by 68% and >95%; respectively, when OHrad was removed. This suggests that OHrad radicals significantly impact the formation of these products. Nitric oxide (NO) did not significantly affect the molar yields of limonaketone or IPOH. However, NO (20 ppb) considerably decreased the molar reaction product yields of 7H6O (62%), 2A5O (63%), and 3A6O (47%), suggesting NO reacted with peroxyl intermediates, generated during limonene ozonolysis, to form other carbonyls (not detected) or organic nitrates. These studies give insight into the transformation of limonene and its reaction products that can lead to indoor exposures.

Characterization of Organic Nitrate Formation in Limonene Secondary Organic Aerosol using High-Resolution Chemical Ionization Mass Spectrometry

Science.gov (United States)

Faxon, Cameron; Hammes, Julia; Peng, Jianfei; Hallquist, Mattias; Pathak, Ravi

2016-04-01

Previous work has shown that organic nitrates (RONO2) are prevalent in the boundary layer, and can contribute significantly to secondary organic aerosol formation. Monoterpenes, including limonene, have been shown to be precursors for the formation of these organic nitrates. Limonene has two double bonds, either of which may be oxidized by NO3 or O3. This leads to the generation of products that can subsequently condense or partition into the particle phase, producing secondary organic aerosol. In order to further elucidate the particle and gas phase product distribution of organic nitrates forming from the reactions of limonene and the nitrate radical (NO3), a series of experiments were performed in the Gothenburg Flow Reactor for Oxidation Studies at Low Temperatures (G-FROST), described by previous work. N2O5 was used as the source for NO3 and NO2, and a characterized diffusion source was used to introduce limonene into the flow reactor. All experiments were conducted in the absence of light, and the concentration of limonene was increased step-wise throughout each experiment to modify the ratio of N2O5to limonene. The experiments were conducted such that both limonene- and N2O5-limited regimes were present. Gas and particle phase products were measured using an iodide High-Resolution Time-of-Flight Mass Spectrometer (HR-ToF-CIMS) coupled to a Filter Inlet for Gases and AEROsols (FIGAERO, and particle size and SOA mass concentrations were derived using a Scanning Mobility Particle Sizer (SMPS). CIMS measurement techniques have previously been employed for the measurement of organic nitrate products of such compounds using multiple reagent ions. The use of this instrumentation allowed for the identification of chemical formulas for gas and particle phase species. The findings from the experiments will be presented in terms of the relative gas-particle partitioning of major products and the effects of N2O5/limonene ratios on product distributions. Additionally, a

Preventive and ameliorating effects of citrus D-limonene on dyslipidemia and hyperglycemia in mice with high-fat diet-induced obesity.

Science.gov (United States)

Jing, Li; Zhang, Yu; Fan, Shengjie; Gu, Ming; Guan, Yu; Lu, Xiong; Huang, Cheng; Zhou, Zhiqin

2013-09-05

D-limonene is a major constituent in citrus essential oil, which is used in various foods as a flavoring agent. Recently, d-limonene has been reported to alleviate fatty liver induced by a high-fat diet. Here we determined the preventive and therapeutic effects of d-limonene on metabolic disorders in mice with high-fat diet-induced obesity. In the preventive treatment, d-limonene decreased the size of white and brown adipocytes, lowered serum triglyceride (TG) and fasting blood glucose levels, and prevented liver lipid accumulations in high-fat diet-fed C57BL/6 mice. In the therapeutic treatment, d-limonene reduced serum TG, low-density lipoprotein cholesterol (LDL-c) and fasting blood glucose levels and glucose tolerance, and increased serum high-density lipoprotein cholesterol (HDL-c) in obese mice. Using a reporter assay and gene expression analysis, we found that d-limonene activated peroxisome proliferator-activated receptor (PPAR)-α signaling, and inhibited liver X receptor (LXR)-β signaling. Our data suggest that the intake of d-limonene may benefit patients with dyslipidemia and hyperglycemia and is a potential dietary supplement for preventing and ameliorating metabolic disorders. © 2013 Elsevier B.V. All rights reserved.

R-Limonene metabolism in humans and metabolite kinetics after oral administration.

Science.gov (United States)

Schmidt, Lukas; Göen, Thomas

2017-03-01

We studied the R-limonene (LMN) metabolism and elimination kinetics in a human in vivo study. Four volunteers were orally exposed to a single LMN dose of 100-130 µg kg -1 bw. In each case, one pre-exposure and subsequently all 24 h post-exposure urine samples were collected. From two subjects, blood samples were drawn up to 5 h after exposure. The parent compound was analysed in blood using headspace GC-MS. The metabolites cis- and trans-carveol (cCAR), perillyl alcohol (POH), perillic acid (PA), limonene-1,2-diol (LMN-1,2-OH), and limonene-8,9-diol (LMN-8,9-OH) were quantified in both blood and urine using GC-PCI-MS/MS. Moreover, GC-PCI-MS full-scan experiments were applied for identification of unknown metabolites in urine. In both matrices, metabolites reached maximum concentrations 1-2 h post-exposure followed by rapid elimination with half-lives of 0.7-2.5 h. In relation to the other metabolites, LMN-1,2-OH was eliminated slowest. Nonetheless, overall renal metabolite elimination was completed within the 24-h observation period. The metabolite amounts excreted via urine corresponded to 0.2 % (cCAR), 0.2 % (tCAR), <0.1 % (POH), 2.0 % (PA), 4.3 % (LMN-1,2-OH), and 32 % (LMN-8,9-OH) of the orally administered dose. GC-PCI-MS full-scan analyses revealed dihydroperillic acid (DHPA) as an additional LMN metabolite. DHPA was estimated to account for 5 % of the orally administered dose. The study revealed that human LMN metabolism proceeds fast and is characterised by oxidation mainly of the exo-cyclic double bond but also of the endo-cyclic double bond and of the methyl side chain. The study results may support the prediction of the metabolism of other terpenes or comparable chemical structures.

The Epoxidation of Limonene over the TS-1 and Ti-SBA-15 Catalysts

Directory of Open Access Journals (Sweden)

Agnieszka Wróblewska

2014-11-01

Full Text Available Limonene belongs to a group of very important intermediates used in the production of fine chemicals. This monoterpene compound can be obtained from peels of oranges or lemon which are a (biomass waste from the orange juice industry. Thus, limonene is a renewable, easy available and a relatively cheap compound. This work presents preliminary studies on the process of limonene epoxidation over zeolite type catalysts such as: TS-1 and Ti-SBA-15. In these studies methanol was used as a solvent and as an oxidizing agent a 60 wt % hydrogen peroxide solution was applied. The activity of each catalyst was investigated for four chosen temperatures (0 °C, 40 °C, 80 °C and 120 °C. The reaction time was changed from 0.5 to 24 h. For each catalyst the most beneficial conditions (the appropriate temperature and the reaction time have been established. The obtained results were compared and the most active catalyst was chosen. These studies have also shown different possible ways of limonene transformation, not only in the direction of 1,2-epoxylimonene and its corresponding diol, but also in direction of carveol, carvone and perillyl alcohol—compounds with a lot of applications. The possible mechanisms of formation of the allylic oxidation products were proposed.

Relationship between peel damage and the accumulation of limonene in four varieties of irradiated oranges

International Nuclear Information System (INIS)

Belli-Donini, M.L.; Baraldi, D.

1977-01-01

The effects of radiation with regard to damage in Citrus fruits are studied in relation to the concentration of limonene, the main component of the oil glands. Control samples of four orange varieties showed no exocarp damage during storage, whereas the irrdiated samples showed varying degrees of browning depending of variety, exposure (100 to 200 krads), storage temperature (5 and 20 0 C) and the ripening stage at which the oranges were irradiated. A correlation has been shown to exist between peel browning during storage and both extracted and volatile limonene content. Irradiation appeared to increase the permeability of the epidermal tissues and the synthesis of limonene. (author)

Antifibrotic effects of D-limonene (5(1-methyl-4-[1-methylethenyl]) cyclohexane) in CCl4 induced liver toxicity in Wistar rats.

Science.gov (United States)

Ahmad, Sheikh Bilal; Rehman, Muneeb U; Fatima, Bilques; Ahmad, Bilal; Hussain, Ishraq; Ahmad, Sheikh Pervaiz; Farooq, Adil; Muzamil, Showkeen; Razzaq, Rahil; Rashid, Shahzada Mudasir; Ahmad Bhat, Showkat; Mir, Manzoor Ur Rahman

2018-03-01

This study was designed to assess the potential antifibrotic effect of D-Limonene-a component of volatile oils extracted from citrus plants. D-limonene is reported to have numerous therapeutic properties. CCl 4 -intduced model of liver fibrosis in Wistar rats is most widely used model to study chemopreventive studies. CCl 4 -intoxication significantly increased serum aminotransferases and total cholesterol these effects were prevented by cotreatment with D-Limonene. Also, CCl 4 -intoxication caused depletion of glutathione and other antioxidant enzymes while D-Limonene preserved them within normal values. Hydroxyproline and malondialdehyde content was increased markedly by CCl 4 treatment while D-Limonene prevented these alterations. Levels of TNF-α, TGF-β, and α-SMA were also assessed; CCl 4 increased the expression of α-SMA, NF-κB and other downstream inflammatory cascade while D-Limonene co-treatment inhibited them. Collectively these findings indicate that D-Limonene possesses potent antifibrotic effect which may be attributed to its antioxidant and anti-inflammatory properties. © 2017 Wiley Periodicals, Inc.

Essential oils as food eco-preservatives: Model system studies on the effect of temperature on limonene antibacterial activity.

Science.gov (United States)

Hąc-Wydro, Katarzyna; Flasiński, Michał; Romańczuk, Karolina

2017-11-15

Antimicrobial properties of essential oils predestine these substances to be used as ecological food preservatives. However, their activity is determined by variety of factors among which external conditions and food properties are highly important. Herein the influence of limonene on artificial membranes was studied to verify the effect of temperature on the incorporation of this compound into model bacterial membrane. The investigations were done on lipid monolayers and the experiments involved the surface pressure-area measurements, penetration studies and Brewster Angle Microscopy analysis. It was found that limonene incorporates into lipid monolayers causing their fluidization. However, the magnitude of alterations depends on limonene concentration, model membrane composition and, for a given composition, on system condensation. Moreover, the influence of limonene is stronger at lower temperatures and, in the light of collected data, this may be a consequence of strong volatility and evaporation of limonene increasing with temperature. Copyright © 2017 Elsevier Ltd. All rights reserved.

Unique base-initiated depolymerization of limonene-derived polycarbonates

NARCIS (Netherlands)

Li, C.; Sablong, R.J.; van Benthem, R.A.T.M.; Koning, C.E.

2017-01-01

The depolymerization of poly(limonene carbonate) (PLC) initiated by 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) was investigated. The strong organic base TBD was capable of deprotonating the OH-terminated PLC, leading to fast degradation via backbiting reactions at high temperature. An interesting

Bioconversion of R-(+)-limonene to perillic acid by the yeast Yarrowia lipolytica

Science.gov (United States)

Ferrara, Maria Antonieta; Almeida, Débora S.; Siani, Antonio C.; Lucchetti, Leonardo; Lacerda, Paulo S.B.; Freitas, André; Tappin, Marcelo R.R.; Bon, Elba P.S.

2013-01-01

Perillyl derivatives are increasingly important due to their flavouring and antimicrobial properties as well as their potential as anticancer agents. These terpenoid species, which are present in limited amounts in plants, may be obtained via bioconversion of selected monoterpene hydrocarbons. In this study, seventeen yeast strains were screened for their ability to oxidize the exocyclic methyl group in the p-menthene moiety of limonene into perillic acid. Of the yeast tested, the highest efficiency was observed for Yarrowia lipolytica ATCC 18942. The conversion of R (+)-limonene by Y. lipolytica was evaluated by varying the pH (3 to 8) and the temperature (25 to 30 °C) in a reaction medium containing 0.5% v/v limonene and 10 g/L of stationary phase cells (dry weight). The best results, corresponding to 564 mg/L of perillic acid, were obtained in buffered medium at pH 7.1 that was incubated at 25 °C for 48 h. The stepwise addition of limonene increased the perillic acid concentration by over 50%, reaching 855 mg/L, whereas the addition of glucose or surfactant to the reaction medium did not improve the bioconversion process. The use of Y. lipolytica showed promise for ease of further downstream processing, as perillic acid was the sole oxidised product of the bioconversion reaction. Moreover, bioprocesses using safe and easy to cultivate yeast cells have been favoured in industry. PMID:24688495

Bioconversion of R-(+-limonene to perillic acid by the yeast Yarrowia lipolytica

Directory of Open Access Journals (Sweden)

Maria Antonieta Ferrara

2013-12-01

Full Text Available Perillyl derivatives are increasingly important due to their flavouring and antimicrobial properties as well as their potential as anticancer agents. These terpenoid species, which are present in limited amounts in plants, may be obtained via bioconversion of selected monoterpene hydrocarbons. In this study, seventeen yeast strains were screened for their ability to oxidize the exocyclic methyl group in the p-menthene moiety of limonene into perillic acid. Of the yeast tested, the highest efficiency was observed for Yarrowia lipolytica ATCC 18942. The conversion of R (+-limonene by Y. lipolytica was evaluated by varying the pH (3 to 8 and the temperature (25 to 30 ºC in a reaction medium containing 0.5% v/v limonene and 10 gµL of stationary phase cells (dry weight. The best results, corresponding to 564 mgµL of perillic acid, were obtained in buffered medium at pH 7.1 that was incubated at 25 ºC for 48 h. The stepwise addition of limonene increased the perillic acid concentration by over 50%, reaching 855 mgµL, whereas the addition of glucose or surfactant to the reaction medium did not improve the bioconversion process. The use of Y. lipolytica showed promise for ease of further downstream processing, as perillic acid was the sole oxidised product of the bioconversion reaction. Moreover, bioprocesses using safe and easy to cultivate yeast cells have been favoured in industry.

Experimental study of the reactions of limonene with OH and OD radicals: kinetics and products.

Science.gov (United States)

Braure, Tristan; Bedjanian, Yuri; Romanias, Manolis N; Morin, Julien; Riffault, Véronique; Tomas, Alexandre; Coddeville, Patrice

2014-10-09

The kinetics of the reactions of limonene with OH and OD radicals has been studied using a low-pressure flow tube reactor coupled with a quadrupole mass spectrometer: OH + C10H16 → products (1), OD + C10H16 → products (2). The rate constants of the title reactions were determined using four different approaches: either monitoring the kinetics of OH (OD) radicals or limonene consumption in excess of limonene or of the radicals, respectively (absolute method), and by the relative rate method using either the reaction OH (OD) + Br2 or OH (OD) + DMDS (dimethyl disulfide) as the reference one and following HOBr (DOBr) formation or DMDS and limonene consumption, respectively. As a result of the absolute and relative measurements, the overall rate coefficients, k1 = (3.0 ± 0.5) × 10(-11) exp((515 ± 50)/T) and k2 = (2.5 ± 0.6) × 10(-11) exp((575 ± 60)/T) cm(3) molecule(-1) s(-1), were determined at a pressure of 1 Torr of helium over the temperature ranges 220-360 and 233-353 K, respectively. k1 was found to be pressure independent over the range 0.5-5 Torr. There are two possible pathways for the reaction between OH (OD) and limonene: addition of the radical to one of the limonene double bonds (reactions 1a and 2a ) and abstraction of a hydrogen atom (reactions 1b and 2b ), resulting in the formation of H2O (HOD). Measurements of the HOD yield as a function of temperature led to the following branching ratio of the H atom abstraction channel: k2b/k2 = (0.07 ± 0.03) × exp((460 ± 140)/T) for T = (253-355) K.

Secondary organic aerosol formation by limonene ozonolysis: Parameterizing multi-generational chemistry in ozone- and residence time-limited indoor environments

Science.gov (United States)

Waring, Michael S.

2016-11-01

Terpene ozonolysis reactions can be a strong source of secondary organic aerosol (SOA) indoors. SOA formation can be parameterized and predicted using the aerosol mass fraction (AMF), also known as the SOA yield, which quantifies the mass ratio of generated SOA to oxidized terpene. Limonene is a monoterpene that is at sufficient concentrations such that it reacts meaningfully with ozone indoors. It has two unsaturated bonds, and the magnitude of the limonene ozonolysis AMF varies by a factor of ∼4 depending on whether one or both of its unsaturated bonds are ozonated, which depends on whether ozone is in excess compared to limonene as well as the available time for reactions indoors. Hence, this study developed a framework to predict the limonene AMF as a function of the ozone [O3] and limonene [lim] concentrations and the air exchange rate (AER, h-1), which is the inverse of the residence time. Empirical AMF data were used to calculate a mixing coefficient, β, that would yield a 'resultant AMF' as the combination of the AMFs due to ozonolysis of one or both of limonene's unsaturated bonds, within the volatility basis set (VBS) organic aerosol framework. Then, β was regressed against predictors of log10([O3]/[lim]) and AER (R2 = 0.74). The β increased as the log10([O3]/[lim]) increased and as AER decreased, having the physical meaning of driving the resultant AMF to the upper AMF condition when both unsaturated bonds of limonene are ozonated. Modeling demonstrates that using the correct resultant AMF to simulate SOA formation owing to limonene ozonolysis is crucial for accurate indoor prediction.

Facile synthesis of (4S)-(-)-[9-3H]limonene

International Nuclear Information System (INIS)

Hiraga, Yoshikazu; Danjo, Hiroshi; Ito, Takatoshi; Suga, Takayuki

1993-01-01

[ 3 H]-1-Methyl-4-(1'-methylethenyl)cyclohexene [ 3 H] limonene) was synthesized from: -2-(4'-methylcyclohex-3'-enyl)propanal -(-)-1-ρ-menthen-9-al) via a convenient route in a high yield with improved enantiomeric purity. (Author)

Methane reacts with heteropolyacids chemisorbed on silica to produce acetic acid under soft conditions

KAUST Repository

Sun, Miao

2013-01-16

Selective functionalization of methane at moderate temperature is of crucial economic, environmental, and scientific importance. Here, we report that methane reacts with heteropolyacids (HPAs) chemisorbed on silica to produce acetic acid under soft conditions. Specially, when chemisorbed on silica, H 4SiW12O40, H3PW12O 40, H4SiMo12O40, and H 3PMo12O40 activate the primary C-H bond of methane at room temperature and atmospheric pressure. With these systems, acetic acid is produced directly from methane, in a single step, in the absence of Pd and without adding CO. Extensive surface characterization by solid-state NMR spectroscopy, IR spectroscopy, cyclic voltammetry, and X-ray photoelectron spectroscopy suggests that C-H activation of methane is triggered by the protons in the HPA-silica interface with concerted reduction of the Keggin cage, leading to water formation and hydration of the interface. This is the simplest and mildest way reported to date to functionalize methane. © 2012 American Chemical Society.

Optimisation of α-terpineol production by limonene biotransformation using Penicillium digitatum DSM 62840.

Science.gov (United States)

Tai, Ya-Nan; Xu, Min; Ren, Jing-Nan; Dong, Man; Yang, Zi-Yu; Pan, Si-Yi; Fan, Gang

2016-02-01

In this study, (R)-(+)-limonene biotransformation using three fungal strains was compared. Penicillium digitatum DSM 62840 was distinguished for its capacity to transform limonene into α-terpineol with high regioselectivity. Growth kinetics in submerged liquid culture and the effects of growth phase and contact time on biotransformation were studied using this strain. Substrate concentration, co-solvent selection, and cultivation conditions were subsequently optimised. The maximum concentration of α-terpineol (833.93 mg L(-1)) was obtained when the pre-culture medium was in medium log-phase by adding 840 mg L(-1) substrate dissolved in ethanol and cultivation was performed at 24 °C, 150 rpm, and pH 6.0 for 12 h. Addition of small amounts of (R)-(+)-limonene (84 mg L(-1)) at the start of fungal log-phase growth yielded a 1.5-fold yield of α-terpineol, indicating that the enzyme was inducible. Among these three strains tested, P. digitatum DSM 62840 was proved to be an efficient biocatalyst to transform (R)-(+)-limonene to α-terpineol. Further studies revealed that the optimal growth phase for biotransformation was in the medium log phase of this strain. The biotransformation represented a wide tolerance of temperature; α-terpineol concentration underwent no significant change at 8-32 °C. The biotransformation could also be performed using resting cells. © 2015 Society of Chemical Industry.

Differential mechanism of Escherichia coli Inactivation by (+)-limonene as a function of cell physiological state and drug's concentration.

Science.gov (United States)

Chueca, Beatriz; Pagán, Rafael; García-Gonzalo, Diego

2014-01-01

(+)-limonene is a lipophilic antimicrobial compound, extracted from citrus fruits' essential oils, that is used as a flavouring agent and organic solvent by the food industry. A recent study has proposed a common and controversial mechanism of cell death for bactericidal antibiotics, in which hydroxyl radicals ultimately inactivated cells. Our objective was to determine whether the mechanism of Escherichia coli MG1655 inactivation by (+)-limonene follows that of bactericidal antibiotics. A treatment with 2,000 μL/L (+)-limonene inactivated 4 log10 cycles of exponentially growing E. coli cells in 3 hours. On one hand, an increase of cell survival in the ΔacnB mutant (deficient in a TCA cycle enzyme), or in the presence of 2,2'-dipyridyl (inhibitor of Fenton reaction by iron chelation), thiourea, or cysteamine (hydroxyl radical scavengers) was observed. Moreover, the ΔrecA mutant (deficient in an enzyme involved in SOS response to DNA damage) was more sensitive to (+)-limonene. Thus, this indirect evidence indicates that the mechanism of exponentially growing E. coli cells inactivation by 2,000 μL/L (+)-limonene is due to the TCA cycle and Fenton-mediated hydroxyl radical formation that caused oxidative DNA damage, as observed for bactericidal drugs. However, several differences have been observed between the proposed mechanism for bactericidal drugs and for (+)-limonene. In this regard, our results demonstrated that E. coli inactivation was influenced by its physiological state and the drug's concentration: experiments with stationary-phase cells or 4,000 μL/L (+)-limonene uncovered a different mechanism of cell death, likely unrelated to hydroxyl radicals. Our research has also shown that drug's concentration is an important factor influencing the mechanism of bacterial inactivation by antibiotics, such as kanamycin. These results might help in improving and spreading the use of (+)-limonene as an antimicrobial compound, and in clarifying the controversy about

Gene discovery for enzymes involved in limonene modification or utilization by the mountain pine beetle-associated pathogen Grosmannia clavigera.

Science.gov (United States)

Wang, Ye; Lim, Lynette; Madilao, Lina; Lah, Ljerka; Bohlmann, Joerg; Breuil, Colette

2014-08-01

To successfully colonize and eventually kill pine trees, Grosmannia clavigera (Gs cryptic species), the main fungal pathogen associated with the mountain pine beetle (Dendroctonus ponderosae), has developed multiple mechanisms to overcome host tree chemical defenses, of which terpenoids are a major component. In addition to a monoterpene efflux system mediated by a recently discovered ABC transporter, Gs has genes that are highly induced by monoterpenes and that encode enzymes that modify or utilize monoterpenes [especially (+)-limonene]. We showed that pine-inhabiting Ophiostomale fungi are tolerant to monoterpenes, but only a few, including Gs, are known to utilize monoterpenes as a carbon source. Gas chromatography-mass spectrometry (GC-MS) revealed that Gs can modify (+)-limonene through various oxygenation pathways, producing carvone, p-mentha-2,8-dienol, perillyl alcohol, and isopiperitenol. It can also degrade (+)-limonene through the C-1-oxygenated pathway, producing limonene-1,2-diol as the most abundant intermediate. Transcriptome sequencing (RNA-seq) data indicated that Gs may utilize limonene 1,2-diol through beta-oxidation and then valine and tricarboxylic acid (TCA) metabolic pathways. The data also suggested that at least two gene clusters, located in genome contigs 108 and 161, were highly induced by monoterpenes and may be involved in monoterpene degradation processes. Further, gene knockouts indicated that limonene degradation required two distinct Baeyer-Villiger monooxygenases (BVMOs), an epoxide hydrolase and an enoyl coenzyme A (enoyl-CoA) hydratase. Our work provides information on enzyme-mediated limonene utilization or modification and a more comprehensive understanding of the interaction between an economically important fungal pathogen and its host's defense chemicals.

Limonene and tetrahydrofurfuryl alcohol cleaning agent

Science.gov (United States)

Bohnert, George W.; Carter, Richard D.; Hand, Thomas E.; Powers, Michael T.

1996-05-07

The present invention is a tetrahydrofurfuryl alcohol and limonene or terpineol cleaning agent and method for formulating and/or using the cleaning agent. This cleaning agent effectively removes both polar and nonpolar contaminants from various electrical and mechanical parts and is readily used without surfactants, thereby reducing the need for additional cleaning operations. The cleaning agent is warm water rinsable without the use of surfactants. The cleaning agent can be azeotropic, enhancing ease of use in cleaning operations and ease of recycling.

Limonene and tetrahydrofurfurly alcohol cleaning agent

Science.gov (United States)

Bohnert, George W.; Carter, Richard D.; Hand, Thomas E.; Powers, Michael T.

1997-10-21

The present invention is a tetrahydrofurfuryl alcohol and limonene cleaning agent and method for formulating and/or using the cleaning agent. This cleaning agent effectively removes both polar and nonpolar contaminants from various electrical and mechanical parts and is readily used without surfactants, thereby reducing the need for additional cleaning operations. The cleaning agent is warm water rinsable without the use of surfactants. The cleaning agent can be azeotropic, enhancing ease of use in cleaning operations and ease of recycling.

Engineering Limonene and Bisabolene Production in Wild Type and a Glycogen-Deficient Mutant of Synechococcus sp. PCC 7002

Energy Technology Data Exchange (ETDEWEB)

Davies, Fiona K., E-mail: fdavies@mines.edu [Department of Chemistry and Geochemistry, Colorado School of Mines, Golden, CO (United States); Work, Victoria H. [Civil and Environmental Engineering Division, Colorado School of Mines, Golden, CO (United States); Beliaev, Alexander S. [Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA (United States); Posewitz, Matthew C. [Department of Chemistry and Geochemistry, Colorado School of Mines, Golden, CO (United States)

2014-06-19

The plant terpenoids limonene (C{sub 10}H{sub 16}) and α-bisabolene (C{sub 15}H{sub 24}) are hydrocarbon precursors to a range of industrially relevant chemicals. High-titer microbial synthesis of limonene and α-bisabolene could pave the way for advances in in vivo engineering of tailor-made hydrocarbons, and production at commercial scale. We have engineered the fast-growing unicellular euryhaline cyanobacterium Synechococcus sp. PCC 7002 to produce yields of 4 mg L{sup −1} limonene and 0.6 mg L{sup −1} α-bisabolene through heterologous expression of the Mentha spicatal-limonene synthase or the Abies grandis (E)-α-bisabolene synthase genes, respectively. Titers were significantly higher when a dodecane overlay was applied during culturing, suggesting either that dodecane traps large quantities of volatile limonene or α-bisabolene that would otherwise be lost to evaporation, and/or that continuous product removal in dodecane alleviates product feedback inhibition to promote higher rates of synthesis. We also investigate limonene and bisabolene production in the ΔglgC genetic background, where carbon partitioning is redirected at the expense of glycogen biosynthesis. The Synechococcus sp. PCC 7002 ΔglgC mutant excreted a suite of overflow metabolites (α-ketoisocaproate, pyruvate, α-ketoglutarate, succinate, and acetate) during nitrogen-deprivation, and also at the onset of stationary growth in nutrient-replete media. None of the excreted metabolites, however, appeared to be effectively utilized for terpenoid metabolism. Interestingly, we observed a 1.6- to 2.5-fold increase in the extracellular concentration of most excreted organic acids when the ΔglgC mutant was conferred with the ability to produce limonene. Overall, Synechococcus sp. PCC 7002 provides a highly promising platform for terpenoid biosynthetic and metabolic engineering efforts.

Engineering limonene and bisabolene production in wild type and a glycogen-deficient mutant of Synechococcus sp. PCC 7002

Energy Technology Data Exchange (ETDEWEB)

Davies, Fiona K.; Work, Victoria H.; Beliaev, Alex S.; Posewitz, Matthew C.

2014-06-19

The plant terpenoids limonene (C10H16) and α-bisabolene (C15H24) are hydrocarbon precursors to a range of industrially-relevant chemicals. High-titer microbial synthesis of limonene and α- bisabolene could pave the way for advances in in vivo engineering of tailor-made hydrocarbons, and production at commercial scale. We have engineered the fast-growing unicellular euryhaline cyanobacterium Synechococcus sp. PCC 7002 to produce yields of 4 mg L-1 limonene and 0.6 mg L-1 α-bisabolene through heterologous expression of the Mentha spicata L-limonene synthase or the Abies grandis (E)-α-bisabolene synthase genes, respectively. Titers were significantly higher when a dodecane overlay was applied during culturing, suggesting either that dodecane traps large quantities of volatile limonene and α-bisabolene that would otherwise be lost to evaporation, and/or that continuous product removal in dodecane alleviates product feedback inhibition to promote higher rates of synthesis. We also investigate limonene and bisabolene production in the ΔglgC genetic background, where carbon partitioning is redirected at the expense of glycogen biosynthesis. The Synechococcus sp. PCC 7002 ΔglgC mutant excreted a suite of overflow metabolites (α-ketoisocaproate, pyruvate, α-ketoglutarate, succinate and acetate) during nitrogen deprivation, and also at the onset of stationary growth in nutrient-replete media. None of the excreted metabolites, however, appeared to be effectively utilized for terpenoid metabolism. Interestingly, we observed a 1.6 to 2.5-fold increase in the extracellular concentration of most excreted organic acids when the ΔglgC mutant was conferred with the ability to produce limonene. Overall, Synechococcus sp. PCC 7002 provides a highly promising platform for terpenoid biosynthetic and metabolic engineering efforts.

Engineering Limonene and Bisabolene Production in Wild Type and a Glycogen-Deficient Mutant of Synechococcus sp. PCC 7002.

Science.gov (United States)

Davies, Fiona K; Work, Victoria H; Beliaev, Alexander S; Posewitz, Matthew C

2014-01-01

The plant terpenoids limonene (C10H16) and α-bisabolene (C15H24) are hydrocarbon precursors to a range of industrially relevant chemicals. High-titer microbial synthesis of limonene and α-bisabolene could pave the way for advances in in vivo engineering of tailor-made hydrocarbons, and production at commercial scale. We have engineered the fast-growing unicellular euryhaline cyanobacterium Synechococcus sp. PCC 7002 to produce yields of 4 mg L(-1) limonene and 0.6 mg L(-1) α-bisabolene through heterologous expression of the Mentha spicatal-limonene synthase or the Abies grandis (E)-α-bisabolene synthase genes, respectively. Titers were significantly higher when a dodecane overlay was applied during culturing, suggesting either that dodecane traps large quantities of volatile limonene or α-bisabolene that would otherwise be lost to evaporation, and/or that continuous product removal in dodecane alleviates product feedback inhibition to promote higher rates of synthesis. We also investigate limonene and bisabolene production in the ΔglgC genetic background, where carbon partitioning is redirected at the expense of glycogen biosynthesis. The Synechococcus sp. PCC 7002 ΔglgC mutant excreted a suite of overflow metabolites (α-ketoisocaproate, pyruvate, α-ketoglutarate, succinate, and acetate) during nitrogen-deprivation, and also at the onset of stationary growth in nutrient-replete media. None of the excreted metabolites, however, appeared to be effectively utilized for terpenoid metabolism. Interestingly, we observed a 1.6- to 2.5-fold increase in the extracellular concentration of most excreted organic acids when the ΔglgC mutant was conferred with the ability to produce limonene. Overall, Synechococcus sp. PCC 7002 provides a highly promising platform for terpenoid biosynthetic and metabolic engineering efforts.

Engineering Limonene and Bisabolene Production in Wild Type and a Glycogen-Deficient Mutant of Synechococcus sp. PCC 7002

International Nuclear Information System (INIS)

Davies, Fiona K.; Work, Victoria H.; Beliaev, Alexander S.; Posewitz, Matthew C.

2014-01-01

The plant terpenoids limonene (C 10 H 16 ) and α-bisabolene (C 15 H 24 ) are hydrocarbon precursors to a range of industrially relevant chemicals. High-titer microbial synthesis of limonene and α-bisabolene could pave the way for advances in in vivo engineering of tailor-made hydrocarbons, and production at commercial scale. We have engineered the fast-growing unicellular euryhaline cyanobacterium Synechococcus sp. PCC 7002 to produce yields of 4 mg L −1 limonene and 0.6 mg L −1 α-bisabolene through heterologous expression of the Mentha spicatal-limonene synthase or the Abies grandis (E)-α-bisabolene synthase genes, respectively. Titers were significantly higher when a dodecane overlay was applied during culturing, suggesting either that dodecane traps large quantities of volatile limonene or α-bisabolene that would otherwise be lost to evaporation, and/or that continuous product removal in dodecane alleviates product feedback inhibition to promote higher rates of synthesis. We also investigate limonene and bisabolene production in the ΔglgC genetic background, where carbon partitioning is redirected at the expense of glycogen biosynthesis. The Synechococcus sp. PCC 7002 ΔglgC mutant excreted a suite of overflow metabolites (α-ketoisocaproate, pyruvate, α-ketoglutarate, succinate, and acetate) during nitrogen-deprivation, and also at the onset of stationary growth in nutrient-replete media. None of the excreted metabolites, however, appeared to be effectively utilized for terpenoid metabolism. Interestingly, we observed a 1.6- to 2.5-fold increase in the extracellular concentration of most excreted organic acids when the ΔglgC mutant was conferred with the ability to produce limonene. Overall, Synechococcus sp. PCC 7002 provides a highly promising platform for terpenoid biosynthetic and metabolic engineering efforts.

Citrus waste as feedstock for bio-based products recovery: Review on limonene case study and energy valorization.

Science.gov (United States)

Negro, Viviana; Mancini, Giuseppe; Ruggeri, Bernardo; Fino, Debora

2016-08-01

The citrus peels and residue of fruit juices production are rich in d-limonene, a cyclic terpene characterized by antimicrobial activity, which could hamper energy valorization bioprocess. Considering that limonene is used in nutritional, pharmaceutical and cosmetic fields, citrus by-products processing appear to be a suitable feedstock either for high value product recovery or energy bio-processes. This waste stream, more than 10MTon at 2013 in European Union (AIJN, 2014), can be considered appealing, from the view point of conducting a key study on limonene recovery, as its content of about 1%w/w of high value-added molecule. Different processes are currently being studied to recover or remove limonene from citrus peel to both prevent pollution and energy resources recovery. The present review is aimed to highlight pros and contras of different approaches suggesting an energy sustainability criterion to select the most effective one for materials and energy valorization. Copyright © 2016 Elsevier Ltd. All rights reserved.

The lasting effect of limonene-induced particle formation on air quality in a genuine indoor environment.

Science.gov (United States)

Rösch, Carolin; Wissenbach, Dirk K; von Bergen, Martin; Franck, Ulrich; Wendisch, Manfred; Schlink, Uwe

2015-09-01

Atmospheric ozone-terpene reactions, which form secondary organic aerosol (SOA) particles, can affect indoor air quality when outdoor air mixes with indoor air during ventilation. This study, conducted in Leipzig, Germany, focused on limonene-induced particle formation in a genuine indoor environment (24 m(3)). Particle number, limonene and ozone concentrations were monitored during the whole experimental period. After manual ventilation for 30 min, during which indoor ozone levels reached up to 22.7 ppb, limonene was introduced into the room at concentrations of approximately 180 to 250 μg m(-3). We observed strong particle formation and growth within a diameter range of 9 to 50 nm under real-room conditions. Larger particles with diameters above 100 nm were less affected by limonene introduction. The total particle number concentrations (TPNCs) after limonene introduction clearly exceed outdoor values by a factor of 4.5 to 41 reaching maximum concentrations of up to 267,000 particles cm(-3). The formation strength was influenced by background particles, which attenuated the formation of new SOA with increasing concentration, and by ozone levels, an increase of which by 10 ppb will result in a six times higher TPNC. This study emphasizes indoor environments to be preferred locations for particle formation and growth after ventilation events. As a consequence, SOA formation can produce significantly higher amounts of particles than transported by ventilation into the indoor air.

Theoretical investigations of the gas phase reaction of limonene (C10H16) with OH radical

Science.gov (United States)

Ranjan Dash, Manas; Rajakumar, B.

2015-11-01

The rate coefficients of hydroxyl radical (OH) reaction with limonene were computed using canonical variational transition state theory with small-curvature tunnelling between 275 and 400 K. The geometries and frequencies of all the stationary points are calculated using hybrid density functional theory methods M06-2X and MPWB1K with 6-31+G(d,p), 6-311++G(d,p), and 6-311+G(2df,2p) basis sets. Both addition and abstraction channels of the title reaction were explored. The rate coefficients obtained over the temperature range of 275-400 K were used to derive the Arrhenius expressions: k(T) = 4.06×10-34 T7.07 exp[4515/T] and k(T) = 7.37×10-25 T3.9 exp[3169/T] cm3 molecule-1 s-1 at M06-2X/6-311+G(2df,2p) and MPWB1K/6-311+G(2df,2p) levels of theory, respectively. Kinetic study indicated that addition reactions are major contributors to the total reaction in the studied temperature range. The atmospheric lifetime (τ) of limonene due to its reactions with various tropospheric oxidants was calculated and concluded that limonene is lost in the atmosphere within a few hours after it is released. The ozone production potential of limonene was computed to be (14-18) ppm, which indicated that degradation of limonene would lead to a significant amount of ozone production in the troposphere.

Improvement of biogas production from orange peel waste by leaching of limonene.

Science.gov (United States)

Wikandari, Rachma; Nguyen, Huong; Millati, Ria; Niklasson, Claes; Taherzadeh, Mohammad J

2015-01-01

Limonene is present in orange peel wastes and is known as an antimicrobial agent, which impedes biogas production when digesting the peels. In this work, pretreatment of the peels to remove limonene under mild condition was proposed by leaching of limonene using hexane as solvent. The pretreatments were carried out with homogenized or chopped orange peel at 20-40°C with orange peel waste and hexane ratio (w/v) ranging from 1 : 2 to 1 : 12 for 10 to 300 min. The pretreated peels were then digested in batch reactors for 33 days. The highest biogas production was achieved by treating chopped orange peel waste and hexane ratio of 12 : 1 at 20°C for 10 min corresponding to more than threefold increase of biogas production from 0.061 to 0.217 m(3) methane/kg VS. The solvent recovery was 90% using vacuum filtration and needs further separation using evaporation. The hexane residue in the peel had a negative impact on biogas production as shown by 28.6% reduction of methane and lower methane production of pretreated orange peel waste in semicontinuous digestion system compared to that of untreated peel.

Limonene reduces hyperalgesia induced by gp120 and cytokines by modulation of IL-1 β and protein expression in spinal cord of mice.

Science.gov (United States)

Piccinelli, Ana Claudia; Morato, Priscila Neder; Dos Santos Barbosa, Marcelo; Croda, Julio; Sampson, Jared; Kong, Xiangpeng; Konkiewitz, Elisabete Castelon; Ziff, Edward B; Amaya-Farfan, Jaime; Kassuya, Cândida Aparecida Leite

2017-04-01

We have investigated the antihyperalgesic effects of limonene in mice that received intrathecal injection of gp120. Male Swiss mice received gp120, IL-1β or TNF-α intrathecally or sterile saline as a control. A mechanical sensitivity test was performed at 2 and 3h after the injection. Spinal cord and blood samples were isolated for protein quantification. Intrathecal administration of gp120 increased mechanical sensitivity measured with an electronic Von Frey apparatus, at 2 and 3h after the injections. Limonene administered orally prior to gp120 administration significantly decreased this mechanical sensitivity at 3h after the gp120 injection. In addition, intrathecal injection of gp120 increased IL-1β and IL-10 in serum, and limonene prevented the ability of gp120 to increase these cytokines. Limonene also inhibited TNF-α and IL-1β-induced mechanical hyperalgesia. Western blot assay demonstrated limonene was capable of increasing SOD expression in the cytoplasm of cells from spinal cord at 4h after intrathecal IL-1β injection. These results demonstrate that gp120 causes mechanical hyperalgesia and a peripheral increase in IL-1β and IL-10, and that prior administration of limonene inhibits these changes. Also limonene modulates the activation of SOD expression in the spinal cord after spinal IL-1β application. The ability of limonene to inhibit the mechanical hyperalgesia induced by gp120, TNF-α and IL-1β emphasizes the anti-inflammatory action of limonene, specifically its ability to inhibit cytokine production and its consequences. Copyright © 2016. Published by Elsevier Inc.

Epoxidation of limonene over Ti MCM 41 and Ti BETA

International Nuclear Information System (INIS)

Cubillos Lobo, Jairo Antonio; Gonzalez Rodriguez, Lina Maria; Montes de Correa, Consuelo

2002-01-01

Ti MCM 41 were synthesized and evaluated in the epoxidation of limonene, using peroxide of hydrogen (H 2 O) as agent oxidizer. The characteristic hexagonal phase of Ti MCM 41 was obtained by heating the precursor gel during three days at 100 centigrade degrees. Further heating up to ten days leads to a decrease of this phase. The increase (Ti) in the synthesis gel also decreases that phase. The increase of Ti in the synthesis gel also decreases that phase UV VIS and FTIR spectroscopy indicates that Ti was incorporated in the lattice of Ti MCM 41 as well as, in Ti BETA. SEM micrographs of Ti MCM 41 show that the morphology changes with the Ti loading. Ti MCM 41 was most active than Ti BETA for limonene epoxidation even though both show high selectivity to epoxides

Limonene dehydrogenase hydroxylates the allylic methyl group of cyclic monoterpenes in the anaerobic terpene degradation by Castellaniella defragrans.

Science.gov (United States)

Puentes-Cala, Edinson; Liebeke, Manuel; Markert, Stephanie; Harder, Jens

2018-05-01

The enzymatic functionalization of hydrocarbons is a central step in the global carbon cycle initiating the mineralization of methane, isoprene and monoterpenes, the most abundant biologically produced hydrocarbons. Also, terpene-modifying enzymes have found many applications in the energy-economic biotechnological production of fine chemicals. Here we describe a limonene dehydrogenase that was purified from the facultatively anaerobic betaproteobacterium Castellaniella defragrans 65Phen grown on monoterpenes under denitrifying conditions in the absence of molecular oxygen. The purified limonene:ferrocenium oxidoreductase activity hydroxylated the methyl group of limonene (1-methyl-4-(1-methylethenyl)-cyclohex-1-ene) yielding perillyl alcohol ([4-(prop-1-en-2-yl)cyclohex-1-en-1-yl]methanol). The enzyme had a dithiothreitol:perillyl alcohol oxidoreductase activity yielding limonene. Mass spectrometry and molecular size determinations revealed a heterodimeric enzyme comprising CtmA and CtmB. Recently the two proteins had been identified by transposon mutagenesis and proteomics as part of the cyclic terpene metabolism ( ctm ) in Castellaniella defragrans and were annotated as FAD-dependent oxidoreductases of the protein domain family phytoene dehydrogenases and related proteins (COG1233). CtmAB is the first heterodimeric enzyme in this protein superfamily. Flavins in the purified CtmAB are oxidized by ferrocenium and are reduced by limonene. Heterologous expression of CtmA, CtmB and CtmAB in E. coli demonstrated that limonene dehydrogenase activity required both subunits carrying each a flavin cofactor. Native CtmAB oxidized a wide range of monocyclic monoterpenes containing the allylic methyl group motif (1-methyl-cyclohex-1-ene). In conclusion, we have identified CtmAB as a hydroxylating limonene dehydrogenase and the first heteromer in a family of FAD-dependent dehydrogenases acting on allylic methylene or methyl CH-bonds. We suggest a placement in EC 1

Oxidative degradation of toluene and limonene in air by pulsed corona technology

International Nuclear Information System (INIS)

Hoeben, W F L M; Beckers, F J C M; Pemen, A J M; Van Heesch, E J M; Kling, W L

2012-01-01

The oxidative degradation of two volatile organic compounds, i.e. toluene (fossil fuel based VOC) and limonene (biogenic VOC), has been studied. A hybrid pulsed power corona reactor with adjustable energy density has been utilized for degradation of ppm level target compounds in large air flows. The observed oxidation product range features an energy density-dependent spectrum of oxygen-functional hydrocarbons, which has been qualitatively discussed on the basis of literature studies. Typically, observed stable oxidation products for both target compounds are the biocompatible carboxylic acids acetic and formic acid. Measured degradation G-values are 23 nmol J -1 at 74% conversion of 70 ppm toluene and 181 nmol J -1 at 81% conversion of 10 ppm limonene. (paper)

Improvement of Biogas Production from Orange Peel Waste by Leaching of Limonene

Science.gov (United States)

Wikandari, Rachma; Nguyen, Huong; Millati, Ria; Niklasson, Claes; Taherzadeh, Mohammad J.

2015-01-01

Limonene is present in orange peel wastes and is known as an antimicrobial agent, which impedes biogas production when digesting the peels. In this work, pretreatment of the peels to remove limonene under mild condition was proposed by leaching of limonene using hexane as solvent. The pretreatments were carried out with homogenized or chopped orange peel at 20–40°C with orange peel waste and hexane ratio (w/v) ranging from 1 : 2 to 1 : 12 for 10 to 300 min. The pretreated peels were then digested in batch reactors for 33 days. The highest biogas production was achieved by treating chopped orange peel waste and hexane ratio of 12 : 1 at 20°C for 10 min corresponding to more than threefold increase of biogas production from 0.061 to 0.217 m3 methane/kg VS. The solvent recovery was 90% using vacuum filtration and needs further separation using evaporation. The hexane residue in the peel had a negative impact on biogas production as shown by 28.6% reduction of methane and lower methane production of pretreated orange peel waste in semicontinuous digestion system compared to that of untreated peel. PMID:25866787

Improvement of Biogas Production from Orange Peel Waste by Leaching of Limonene

Directory of Open Access Journals (Sweden)

Rachma Wikandari

2015-01-01

Full Text Available Limonene is present in orange peel wastes and is known as an antimicrobial agent, which impedes biogas production when digesting the peels. In this work, pretreatment of the peels to remove limonene under mild condition was proposed by leaching of limonene using hexane as solvent. The pretreatments were carried out with homogenized or chopped orange peel at 20–40°C with orange peel waste and hexane ratio (w/v ranging from 1 : 2 to 1 : 12 for 10 to 300 min. The pretreated peels were then digested in batch reactors for 33 days. The highest biogas production was achieved by treating chopped orange peel waste and hexane ratio of 12 : 1 at 20°C for 10 min corresponding to more than threefold increase of biogas production from 0.061 to 0.217 m3 methane/kg VS. The solvent recovery was 90% using vacuum filtration and needs further separation using evaporation. The hexane residue in the peel had a negative impact on biogas production as shown by 28.6% reduction of methane and lower methane production of pretreated orange peel waste in semicontinuous digestion system compared to that of untreated peel.

HIGH-PRESSURE VAPOR-LIQUID EQUILIBRIUM DATA FOR BINARY AND TERNARY SYSTEMS FORMED BY SUPERCRITICAL CO2, LIMONENE AND LINALOOL

Directory of Open Access Journals (Sweden)

MELO S. A. B. VIEIRA DE

1999-01-01

Full Text Available The feasibility of deterpenating orange peel oil with supercritical CO2 depends on relevant vapor-liquid equilibrium data because the selectivity of this solvent for limonene and linalool (the two key components of the oil is of crucial importance. The vapor-liquid equilibrium data of the CO2-limonene binary system was measured at 50, 60 and 70oC and pressures up to 10 MPa, and of the CO2-linalool binary system at 50oC and pressures up to 85 bar. These results were compared with published data when available in the literature. The unpublished ternary phase equilibrium of CO2-limonene-linalool was studied at 50oC and up to 9 MPa. Selectivities obtained using these ternary data were compared with those calculated using binary data and indicate that a selective separation of limonene and linalool can be achieved.

Tungstophosphoric acid supported onto hydrous zirconia ...

Indian Academy of Sciences (India)

Unknown

Hydrous zirconia; heteropolyacid; morphology; particle size; acidity. 1. Introduction. Catalysis by .... chemisorbed on the sample in every pulse was detected by a thermal ..... qualitative organic analysis (New York: Longman), Ch. 3,. 4th ed.

Biotransformation of d-Limonene to (+) trans-Carveol by Toluene-Grown Rhodococcus opacus PWD4 Cells

Science.gov (United States)

Duetz, Wouter A.; Fjällman, Ann H. M.; Ren, Shuyu; Jourdat, Catherine; Witholt, Bernard

2001-01-01

The toluene-degrading strain Rhodococcus opacus PWD4 was found to hydroxylate d-limonene exclusively in the 6-position, yielding enantiomerically pure (+) trans-carveol and traces of (+) carvone. This biotransformation was studied using cells cultivated in chemostat culture with toluene as a carbon and energy source. The maximal specific activity of (+) trans-carveol formation was 14.7 U (g of cells [dry weight])−1, and the final yield was 94 to 97%. Toluene was found to be a strong competitive inhibitor of the d-limonene conversion. Glucose-grown cells did not form any trans-carveol from d-limonene. These results suggest that one of the enzymes involved in toluene degradation is responsible for this allylic monohydroxylation. Another toluene degrader (Rhodococcus globerulus PWD8) had a lower specific activity but was found to oxidize most of the formed trans-carveol to (+) carvone, allowing for the biocatalytic production of this flavor compound. PMID:11375201

Not only oxidized R-(+)- but also S-(-)- limonene is a common cause of contact allergy in dermatitis patients in Europe

DEFF Research Database (Denmark)

Matura, M.; Skold, M.; Borje, A.

2006-01-01

proven to be a good and frequent indicator of fragrance-related contact allergy. The current study extends these investigations to 6 European clinics of dermatology, where the oxidation mixture of both enantiomers of limonene (R and S) have been tested in 2411 dermatitis patients. Altogether, 63 out......, colophonium, Myroxylon pereirae, and fragrance-related contact allergy were common in patients reacting to 1 or both the oxidized limonene enantiomers. Our study provides clinical evidence for the importance of oxidation products of limonene in contact allergy. It seems advisable to screen consecutive...

D-limonene suppresses doxorubicin-induced oxidative stress and inflammation via repression of COX-2, iNOS, and NFκB in kidneys of Wistar rats.

Science.gov (United States)

Rehman, Muneeb U; Tahir, Mir; Khan, Abdul Quaiyoom; Khan, Rehan; Oday-O-Hamiza; Lateef, Abdul; Hassan, Syed Kazim; Rashid, Sumaya; Ali, Nemat; Zeeshan, Mirza; Sultana, Sarwat

2014-04-01

D-limonene is a naturally occurring monoterpene and has been found to posses numerous therapeutic properties. In this study, we used D-limonene as a protective agent against the nephrotoxic effects of anticancer drug doxorubicin (Dox). Rats were given D-limonene at doses of 5% and 10% mixed with diet for 20 consecutive days. Dox was give at the dose of 20 mg/kg body weight intraperitoneally. The protective effects of D-limonene on Dox-induced oxidative stress and inflammation were investigated by assaying oxidative stress biomarkers, lipid peroxidation, serum toxicity markers, proinflammatory cytokines, and expression of nuclear factor kappa B (NFκB), cyclo-oxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS) and Nitrite levels. Administration of Dox (20 mg/kg body weight) in rats enhanced renal lipid peroxidation; depleted glutathione content and anti-oxidant enzymes; elevated levels of kidney toxicity markers viz. kidney injury molecule-1 (KIM-1), blood urea nitrogen (BUN), and creatinine; enhanced expression of NFκB, COX-2, and iNOS and nitric oxide. Treatment with D-limonene prevented oxidative stress by restoring the levels of antioxidant enzymes, further both doses of 5% and 10% showed significant decrease in inflammatory response. Both the doses of D-limonene significantly decreased the levels of kidney toxicity markers KIM-1, BUN, and creatinine. D-limonene also effectively decreased the Dox induced overexpression of NF-κB, COX-2, and iNOS and nitric oxide. Data from the present study indicate the protective role of D-limonene against Dox-induced renal damage.

(Ternary liquid + liquid) equilibria for (water + acetone + α-pinene, or β-pinene, or limonene) mixtures

International Nuclear Information System (INIS)

Li Xiaoli; Tamura, Kazuhiro

2010-01-01

(Ternary liquid + liquid) equilibria (tie-lines) of (water + acetone + α-pinene) at T = (288.15, 298.15, and 308.15) K and (water + acetone + β-pinene, or limonene) at T = 298.15 K have been measured. The experimental (ternary liquid + liquid) equilibrium data have been correlated successfully by the original UNIQUAC and modified UNIQUAC models. The modified UNIQUAC model reproduced accurately the experimental results for the (water + acetone + α-pinene) system at all the temperatures but fairly agreed with the experimental data for the (water + acetone + β-pinene, or limonene) systems.

Recommendation to test limonene hydroperoxides 0·3% and linalool hydroperoxides 1·0% in the British baseline patch test series.

Science.gov (United States)

Wlodek, C; Penfold, C M; Bourke, J F; Chowdhury, M M U; Cooper, S M; Ghaffar, S; Green, C; Holden, C R; Johnston, G A; Mughal, A A; Reckling, C; Sabroe, R A; Stone, N M; Thompson, D; Wilkinson, S M; Buckley, D A

2017-12-01

There is a significant rate of sensitization worldwide to the oxidized fragrance terpenes limonene and linalool. Patch testing to oxidized terpenes is not routinely carried out; the ideal patch test concentration is unknown. To determine the best test concentrations for limonene and linalool hydroperoxides, added to the British baseline patch test series, to optimize detection of true allergy and to minimize irritant reactions. During 2013-2014, 4563 consecutive patients in 12 U.K. centres were tested to hydroperoxides of limonene in petrolatum (pet.) 0·3%, 0·2% and 0·1%, and hydroperoxides of linalool 1·0%, 0·5% and 0·25% pet. Irritant reactions were recorded separately from doubtful reactions. Concomitant reactions to other fragrance markers and clinical relevance were documented. Limonene hydroperoxide 0·3% gave positive reactions in 241 (5·3%) patients, irritant reactions in 93 (2·0%) and doubtful reactions in 110 (2·4%). Linalool hydroperoxide 1·0% gave positive reactions in 352 (7·7%), irritant reactions in 178 (3·9%) and doubtful reactions in 132 (2·9%). A total of 119 patients with crescendo reactions to 0·3% limonene would have been missed if only tested with 0·1% and 131 patients with crescendo reactions to 1·0% linalool would have been missed if only tested with 0·25%. In almost two-thirds of patients with positive patch tests to limonene and linalool the reaction was clinically relevant. The majority of patients did not react to any fragrance marker in the baseline series. We recommend that limonene hydroperoxides be tested at 0·3% and linalool hydroperoxides at 1·0% in the British baseline patch test series. © 2017 British Association of Dermatologists.

Insecticidal, repellent, antimicrobial activity and phytotoxicity of essential oils: With special reference to limonene and its suitability for control of insect pests

Directory of Open Access Journals (Sweden)

M.A. IBRAHIM

2008-12-01

Full Text Available The interest in the use of monoterpenes for insect pest and pathogen control originates from the need for pesticide products with less negative environmental and health impacts than highly effective synthetic pesticides. The expanding literature on the possibility of the use of these monoterpenes is reviewed and focused on the effects of limonene on various bioorganisms. Limonene is used as insecticide to control ectoparasites of pet animals, but it has activity against many insects, mites, and microorganisms. Possible attractive effects of limonene to natural enemies of pests may offer novel applications to use natural compounds for manipulation of beneficial animals in organic agriculture. However, in few cases limonene-treated plants have become attractive to plant damaging insects and phytotoxic effects on cultivated plants have been observed. As a plant-based natural product limonene and other monoterpenes might have use in pest and weed control in organic agriculture after phytotoxicity on crop plants and, effects on non-target soil animals and natural enemies of pest have been investigated

Protective Effect of D-Limonene against Oxidative Stress-Induced Cell Damage in Human Lens Epithelial Cells via the p38 Pathway.

Science.gov (United States)

Bai, Jie; Zheng, Yi; Wang, Gang; Liu, Ping

2016-01-01

Oxidative stress, as mediated by ROS, is a significant factor in initiating the development of age-associated cataracts; D-limonene is a common natural terpene with powerful antioxidative properties which occurs naturally in a wide variety of living organisms. It has been shown to have antioxidant effect; we found that D-limonene can effectively prevent the oxidative damage caused by H2O2 and propose that the main mechanism underlying the inhibitory effects of D-limonene is the inhibition of HLECs apoptosis. In the present study, we used confocal-fluorescence microscopy, flow cytometry analysis, Hoechst staining, H2DCFDA staining, transmission electron microscopy, and immunoblot analysis; the results revealed that slightly higher concentrations of D-limonene (125-1800 μM) reduced the H2O2-induced ROS generation and inhibited the H2O2-induced caspase-3 and caspase-9 activation and decreased the Bcl-2/Bax ratio. Furthermore, it inhibited H2O2-induced p38 MAPK phosphorylation. Thus, we conclude that D-limonene could effectively protect HLECs from H2O2-induced oxidative stress and that its antioxidative effect is significant, thereby increasing the cell survival rate.

Diastereoisomeric diversity dictates reactivity of epoxy groups in limonene dioxide polymerization

Directory of Open Access Journals (Sweden)

M. Soto

2018-06-01

Full Text Available Limonene dioxide (LDO has the potential to find a wide application as a bio-based epoxy resin. Its polymerizations by catalyzed ring-opening, and by polyaddition with diamines were compared with the polymerizations of the commercial epoxy resins bisphenol-A diglycidyl ether (BADGE, and 3,4-epoxycyclohexylmethyl-3′,4′-epoxycyclohexane carboxylate (ECC. Differential scanning calorimetry (DSC studies showed that LDO polymerizations suffer in all cases studied from incomplete conversions. Nuclear magnetic resonance (NMR studies revealed that in cis-isomers of LDO the internal epoxide rings were not reacting. The low reactivity of this epoxide group was explained by mechanistic considerations making use of the Fürst-Plattner rule, or trans-diaxial effect. Due to diastereomeric diversity approximately one-fourth of epoxide groups present in LDO could not react. Therefore, a diastereoselective epoxidation of limonene could provide a fully reactive bio-based epoxy resin.

A high-throughput quantitative expression analysis of cancer-related genes in human HepG2 cells in response to limonene, a potential anticancer agent.

Science.gov (United States)

Hafidh, Rand R; Hussein, Saba Z; MalAllah, Mohammed Q; Abdulamir, Ahmed S; Abu Bakar, Fatimah

2017-11-14

Citrus bioactive compounds, as active anticancer agent, have been under focus by several studies worldwide. However, the underlying genes responsible for the anticancer potential have not been sufficiently highlighted. The current study investigated the gene expression profile of hepatocellular carcinoma, HepG2, cells after treatment with Limonene. The concentration that killed 50% of HepG2 cells was used to elucidate the genetic mechanisms of limonene anticancer activity. The apoptotic induction was detected by flow cytometry and confocal fluorescence microscope. Two of pro-apoptotic events, caspase-3 activation and phosphatidylserine translocation were manifested by confocal fluorescence microscopy. High-throughput real-time PCR was used to profile 1023 cancer-related genes in 16 different gene families related to the cancer development. In comparison to untreated cells, limonene increased the percentage of apoptotic cells up to 89.61%, by flow cytometry, and 48.2% by fluorescence microscopy. There was a significant limonene-driven differential gene expression of HepG2 cells in 15 different gene families. Limonene was shown to significantly (>2log) up-regulate and down-regulate 14 and 59 genes, respectively. The affected gene families, from most to least affected, were apoptosis induction, signal transduction, cancer genes augmentation, alteration in kinases expression, inflammation, DNA damage repair, and cell cycle proteins. The current study reveals that limonene could be a promising, cheap, and effective anticancer compound. The broad spectrum of limonene anticancer activity is interesting for anticancer drug development. Further research is needed to confirm the current findings and to examine the anticancer potential of limonene along with underlying mechanisms on different cell lines. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Pulmonary effects of inhaled limonene ozone reaction products in elderly rats.

Science.gov (United States)

Sunil, Vasanthi R; Laumbach, Robert J; Patel, Kinal J; Turpin, Barbara J; Lim, Ho-Jin; Kipen, Howard M; Laskin, Jeffrey D; Laskin, Debra L

2007-07-15

d-Limonene is an unsaturated volatile organic chemical found in cleaning products, air fresheners and soaps. It is oxidized by ozone to secondary organic aerosols consisting of aldehydes, acids, oxidants and fine and ultra fine particles. The lung irritant effects of these limonene ozone reaction products (LOP) were investigated. Female F344 rats (2- and 18-month-old) were exposed for 3 h to air or LOP formed by reacting 6 ppm d-limonene and 0.8 ppm ozone. BAL fluid, lung tissue and cells were analyzed 0 h and 20 h later. Inhalation of LOP increased TNF-alpha, cyclooxygenase-2, and superoxide dismutase in alveolar macrophages (AM) and Type II cells. Responses of older animals were attenuated when compared to younger animals. LOP also decreased p38 MAP kinase in AM from both younger and older animals. In contrast, while LOP increased p44/42 MAP kinase in AM from younger rats, expression decreased in AM and Type II cells from older animals. NF-kappaB and C/EBP activity also increased in AM from younger animals following LOP exposure but decreased or was unaffected in Type II cells. Whereas in younger animals LOP caused endothelial cell hypertrophy, perivascular and pleural edema and thickening of alveolar septal walls, in lungs from older animals, patchy accumulation of fluid within septal walls in alveolar sacs and subtle pleural edema were noted. LOP are pulmonary irritants inducing distinct inflammatory responses in younger and older animals. This may contribute to the differential sensitivity of these populations to pulmonary irritants.

Pulmonary effects of inhaled limonene ozone reaction products in elderly rats

International Nuclear Information System (INIS)

Sunil, Vasanthi R.; Laumbach, Robert J.; Patel, Kinal J.; Turpin, Barbara J.; Lim, Ho-Jin; Kipen, Howard M.; Laskin, Jeffrey D.; Laskin, Debra L.

2007-01-01

d-Limonene is an unsaturated volatile organic chemical found in cleaning products, air fresheners and soaps. It is oxidized by ozone to secondary organic aerosols consisting of aldehydes, acids, oxidants and fine and ultra fine particles. The lung irritant effects of these limonene ozone reaction products (LOP) were investigated. Female F344 rats (2- and 18-month-old) were exposed for 3 h to air or LOP formed by reacting 6 ppm d-limonene and 0.8 ppm ozone. BAL fluid, lung tissue and cells were analyzed 0 h and 20 h later. Inhalation of LOP increased TNF-α, cyclooxygenase-2, and superoxide dismutase in alveolar macrophages (AM) and Type II cells. Responses of older animals were attenuated when compared to younger animals. LOP also decreased p38 MAP kinase in AM from both younger and older animals. In contrast, while LOP increased p44/42 MAP kinase in AM from younger rats, expression decreased in AM and Type II cells from older animals. NF-κB and C/EBP activity also increased in AM from younger animals following LOP exposure but decreased or was unaffected in Type II cells. Whereas in younger animals LOP caused endothelial cell hypertrophy, perivascular and pleural edema and thickening of alveolar septal walls, in lungs from older animals, patchy accumulation of fluid within septal walls in alveolar sacs and subtle pleural edema were noted. LOP are pulmonary irritants inducing distinct inflammatory responses in younger and older animals. This may contribute to the differential sensitivity of these populations to pulmonary irritants

Ionic fragmentation of a natural product, limonene (C10H16), following core [C 1s] photoionization

International Nuclear Information System (INIS)

Castilho, R.B. de; Nunez, C.V.; Coutinho, L.H.; Lago, A.F.; Bernini, R.B.; Souza, G.G.B. de

2007-01-01

Photoionization of the limonene [C 10 H 16 ] molecule was studied for the first time following C 1s ionization, using synchrotron radiation and time-of-fight mass spectrometry. As a reference for further analysis of the photon induced fragmentation of the limonene molecule, the He(I) mass spectrum was also obtained. Previously unreported singly charged species have been observed at 310 eV: H + , C + , CH + , CH 2 + , CH 3 + . A close similarity has been observed between the high photon energy mass spectrum and the standard electron impact mass spectrum of limonene, obtained at 70 eV. In particular, the base peak [C 5 H 8 + , m/q = 68], known to result from a Retro Diels-Alder reaction, remains the same in both cases. Approximate values for the mean kinetic energy were determined for all ionic species

d -Limonene sensitizes docetaxel-induced cytotoxicity in human prostate cancer cells: Generation of reactive oxygen species and induction of apoptosis

Directory of Open Access Journals (Sweden)

Rabi Thangaiyan

2009-01-01

Full Text Available Background: Clinical trials have shown that docetaxel combined with other novel agents can improve the survival of androgen-independent prostate cancer patients. d -Limonene, a non-nutrient dietary component, has been found to inhibit various cancer cell growths without toxicity. We sought to characterize whether a non-toxic dose of d -limonene may enhance tumor response to docetaxel in an in vitro model of metastatic prostate cancer. Materials and Methods: Human prostate carcinoma DU-145 and normal prostate epithelial PZ-HPV-7 cells were treated with various concentrations of d -limonene, docetaxel or a combination of both, and cell viability was determined by MTT assay. Intracellular reactive oxygen species (ROS, reduced glutathione (GSH and caspase activity were measured. Apoptosis and apoptosis-related proteins were studied by enzyme-linked immunosorbent assay and Western blotting, respectively. Results: d -Limonene and docetaxel in combination significantly enhanced the cytotoxicity to DU-145 cells than PZ-HPV-7 cells. Exposure of DU-145 cells to a combined d -limonene and docetaxel resulted in higher ROS generation, depletion of GSH, accompanied by increased caspase activity than docetaxel alone. It also triggered a series of effects involving cytochrome c , cleavages of caspase-9, 3 and poly (ADP-ribose polymerase, and a shift in Bad:Bcl-xL ratio in favor of apoptosis. Apoptotic effect was significantly blocked on pretreatment with N -acetylcystein, indicating that antitumor effect is initiated by ROS generation, and caspase cascades contribute to the cell death. Conclusion: Our results show, for the first time, that d -limonene enhanced the antitumor effect of docetaxel against prostate cancer cells without being toxic to normal prostate epithelial cells. The combined beneficial effect could be through the modulation of proteins involved in mitochondrial pathway of apoptosis. d -Limonene could be used as a potent non-toxic agent to

Biotransformação de limoneno: uma revisão das principais rotas metabólicas Biotransformation of limonene: a review of the main metabolic pathways

Directory of Open Access Journals (Sweden)

Mário Roberto Maróstica Júnior

2007-04-01

Full Text Available There is considerable progress in the study of the biotransformation of limonene. Extensive research on the biotransformation of limonene has resulted in the elucidation of new metabolic pathways. Natural flavors can be produced via biotransformation, satisfying consumer demand for natural products. This review presents some elements concerning the biotransformation of limonene with emphasis on the metabolic pathways. Some comments are also made on problems related to biocatalysis as well as on the application of some compounds originating from the biotransformation of the inexpensive limonene.

Demonstration that limonene is the first cyclic intermediate in the biosynthesis of oxygenated p-menthane monoterpenes in Mentha piperita and other Mentha species

International Nuclear Information System (INIS)

Croteau, R.; Kjonaas, R.

1983-01-01

The volatile oil of mature Mentha piperita (peppermint) leaves contains as major components the oxygenated p-menthane monoterpenes l-menthol (47%) and l-menthone (24%) as well as very low levels of the monoterpene olefins limonene (1%) and terpinolene (0.1%), which are considered to be probable precursors of the oxygenated derivatives. Immature leaves, which are actively synthesizing monoterpenes, produce an oil with comparatively higher levels of limonene approx.3%), and isolation of the pure olefin showed this compound to consist of approx.80% of the l-(4S)-enantiomer and approx.20% of the d-(4R)-enantiomer. The time course of incorporation of [U- 14 C]sucrose into the monoterpenes of M. piperita shoot tips was consistent with the inital formation of limonene and its subsequent conversion to menthone via pulegone. d,l-[9- 3 H]Limonene and [9,10- 3 H]terpinolene were prepared and tested directly as precursors of oxygenated p-menthane monoterpenes in M. piperita shoot tips. Limonene was readily incorporated into pulegone, menthone, and other oxygenated derivatives, whereas terpinolene was not appreciably incorporated into these compounds. Similarly, d,l-[9- 3 H]limonene was specifically incorporated into pulegone in Mentha pulegium and into the C-2-oxygenated derivative carvone in Mentha spicata, confirming the role of this olefin as the essential precursor of oxygenated p-menthane monoterpenes. Soluble enzyme preparations from the epidermis of immature M. piperita leaves converted the acyclic terpenoid precursor [1- 3 H]geranyl pyrophosphate to limonene as the major cyclic product

Antihyperalgesic and antidepressive actions of (R)-(+)-limonene, α-phellandrene, and essential oil from Schinus terebinthifolius fruits in a neuropathic pain model.

Science.gov (United States)

Piccinelli, Ana Claudia; Santos, Joyce Alencar; Konkiewitz, Elisabete Castelon; Oesterreich, Silvia Aparecida; Formagio, Anelise Samara Nazari; Croda, Julio; Ziff, Edward Benjamim; Kassuya, Cândida Aparecida Leite

2015-07-01

Previous studies have shown that essential oil containing (R)-(+)-limonene and α-phellandrene, extracted from fruits of Schinus terebinthifolius Raddi, exhibit anti-inflammatory activity. This work aimed to verify the antihyperalgesic and antidepressive actions of (R)-(+)-limonene, α-phellandrene, and essential oil from S. terebinthifolius fruits in spared nerve injury (SNI) model of neuropathic pain in rats. In the present work, essential oil from fruits of S. terebinthifolius, as well as the pure (R)-(+)-limonene and α-phellandrene compounds, were assayed for their effects on SNI-induced mechanical and cold hyperalgesia, and depressive-like behavior (immobility in forced swim test) in rats. The locomotor activity was evaluated in open-field test. Oral administration for up to 15 days of essential oil of S. terebinthifolius (100 mg/kg), (R)-(+)-limonene (10 mg/kg), α-phellandrene (10 mg/kg), and also subcutaneous 10 mg/kg dose of ketamine (positive control) significantly inhibited SNI-induced mechanical hyperalgesia and increased immobility in the forced swim test. On the 15th day of oral treatment, α-phellandrene, but neither the essential oil from S. terebinthifolius nor (R)-(+)-limonene, prevented the SNI-induced increase in sensitivity to a cold stimulus. The oral treatment with essential oil (100 mg/kg) or with compounds (10 mg/kg) did not interfere on locomotor activity. Together, the results of the present work show that essential oil of S. terebinthifolius and compounds present in this oil, including (R)-(+)-limonene and α-phellandrene, exhibit antihyperalgesic effects against mechanical hyperalgesia, and are antidepressive, while only α-phellandrene inhibited cold hyperalgesia in SNI rats.

One-pot, one-step synthesis of 2,5-diformylfuran from carbohydrates over Mo-containing Keggin heteropolyacids.

Science.gov (United States)

Liu, Yu; Zhu, Liangfang; Tang, Jinqiang; Liu, Mingyang; Cheng, Ruodi; Hu, Changwei

2014-12-01

In this work, a one-pot strategy for directly converting fructose into 2,5-diformylfuran (DFF) over Mo-containing Keggin heteropolyacids (HPAs) in open air is developed. H3 PMo12 O40 HPA is found to show high activity and selectivity to the formation of DFF owing to its higher Brønsted acidity and moderate redox potential. The partial substitution of the H(+) in H3 PMo12 O40 with Cs(+) leads to the heterogenization of the HPA by forming its cesium salts Csx H3-x PMo12 (x=0.5, 1.5, and 2.5). A satisfactory yield of 69.3% to DFF is obtained over Cs0.5 H2.5 PMo12 polyoxometalate after deliberate optimization of the reaction conditions. The heterogenized polyoxometalate could be recycled and reused without significant loss of catalytic activity for five runs. The produced DFF could be separated from the resulting mixture by an adsorption-desorption method using activated carbon as the adsorbent and furfural as the desorbent. A highest isolated yield of 58.2% is obtained. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A Ta/W mixed addenda heteropolyacid with excellent acid catalytic activity and proton-conducting property

Energy Technology Data Exchange (ETDEWEB)

Li, Shujun; Peng, Qingpo [School of Chemistry and Chemical Engineering, Henan Key Laboratory of Boron Chemistry and Advanced Energy Materials, Henan Normal University, Xinxiang, Henan 453007 (China); Chen, Xuenian, E-mail: xnchen@htu.edu.cn [School of Chemistry and Chemical Engineering, Henan Key Laboratory of Boron Chemistry and Advanced Energy Materials, Henan Normal University, Xinxiang, Henan 453007 (China); Wang, Ruoya; Zhai, Jianxin; Hu, Weihua [School of Chemistry and Chemical Engineering, Henan Key Laboratory of Boron Chemistry and Advanced Energy Materials, Henan Normal University, Xinxiang, Henan 453007 (China); Ma, Fengji, E-mail: fengji.ma@yahoo.com [College of Chemistry and Chemical Engineering, Anyang Normal University, Anyang, Henan 453000 (China); Zhang, Jie, E-mail: jie.zhang@htu.edu.cn [School of Chemistry and Chemical Engineering, Henan Key Laboratory of Boron Chemistry and Advanced Energy Materials, Henan Normal University, Xinxiang, Henan 453007 (China); Liu, Shuxia [Key Laboratory of Polyoxometalates Science of Ministry of Education, College of Chemistry, Northeast Normal University, Changchun City, Jilin 130024 (China)

2016-11-15

A new HPAs H{sub 20}[P{sub 8}W{sub 60}Ta{sub 12}(H{sub 2}O){sub 4}(OH){sub 8}O{sub 236}]·125H{sub 2}O (H-1) which comprises a Ta/W mixed addenda heteropolyanion, 20 protons, and 125 crystalline water molecules has been prepared through ion-exchange method. The structure and properties of H-1 have been explored in detail. AC impedance measurements indicate that H-1 is a good solid state proton conducting material at room temperature with a conductivity value of 7.2×10{sup −3} S cm{sup −1} (25 °C, 30% RH). Cyclic voltammograms of H-1 indicate the electrocatalytic activity towards the reduction of nitrite. Hammett acidity constant H{sub 0} of H-1 in CH{sub 3}CN is −2.91, which is the strongest among the present known HPAs. Relatively, H-1 exhibits excellent catalytic activities toward acetal reaction. - Highlights: • A Ta/W mixed addenda Heteropolyacid (H-1) was isolated. • Hammett acidity constant H{sub 0} of H-1 is the strongest among the present known HPAs. • H-1 exhibits excellent catalytic activities toward acetal reaction. • H-1 is a good solid state proton conducting material at room temperature.

Limonene Arrests Parasite Development and Inhibits Isoprenylation of Proteins in Plasmodium falciparum

Science.gov (United States)

Moura, Ivan Cruz; Wunderlich, Gerhard; Uhrig, Maria L.; Couto, Alicia S.; Peres, Valnice J.; Katzin, Alejandro M.; Kimura, Emília A.

2001-01-01

Isoprenylation is an essential protein modification in eukaryotic cells. Herein, we report that in Plasmodium falciparum, a number of proteins were labeled upon incubation of intraerythrocytic forms with either [3H]farnesyl pyrophosphate or [3H]geranylgeranyl pyrophosphate. By thin-layer chromatography, we showed that attached isoprenoids are partially modified to dolichol and other, uncharacterized, residues, confirming active isoprenoid metabolism in this parasite. Incubation of blood-stage P. falciparum treated with the isoprenylation inhibitor limonene significantly decreased the parasites' progression from the ring stage to the trophozoite stage and at 1.22 mM, 50% of the parasites died after the first cycle. Using Ras- and Rap-specific monoclonal antibodies, putative Rap and Ras proteins of P. falciparum were immunoprecipitated. Upon treatment with 0.5 mM limonene, isoprenylation of these proteins was significantly decreased, possibly explaining the observed arrest of parasite development. PMID:11502528

Limonene: attractant kairomone for white pine cone beetles (Coleoptera: Scolytidae) in an Eastern white pine seed orchard in Western North Carolina

Science.gov (United States)

Daniel R. Miller

2007-01-01

I report on the attraction of the white pine cone beetle, Canophthorus coniperda (Schwarz) (Coleoptera: Scolytidae), to traps baited with the host monoterpene limonene in western North Carolina. Both (+)- and (-)-limonene attracted male and female cone beetles to Japenese beetle traps in an eastern white pine, Pinus strobus L. seed...

Assessment of the Thermodynamic Properties of DL-p-Mentha-1,8-diene, 4-Isopropyl-1-Methylcyclohexene (DL-limonene) by Inverse Gas Chromatography (IGC).

Science.gov (United States)

Farshchi, Negin; Abbasian, Ali; Larijani, Kambiz

2018-05-10

Limonene is a colorless liquid hydrocarbon and had been investigated as a plasticizer for many plastics. Prediction of solubility between different materials is an advantage in many ways, one of the most convenient ways to know the compatibility of materials is to determine the degree of solubility of them in each other. The concept of "solubility parameter" can help practitioners in this way.In this study, inverse gas chromatography (IGC) method at infinite dilution was used for determination of the thermodynamic properties of DL-p-mentha-1,8-diene, 4-Isopropyl-1-methylcyclohexene (DL-limonene). The interaction between DL-limonene and 13 solvents were examined in the temperature range of 63-123°C through the assessment of the thermodynamic sorption parameters, the parameters of mixing at infinite dilution, the weight fraction activity coefficient and the Flory-Huggins interaction parameters. Additionally, the solubility parameter for DL-limonene and the temperature dependence of these parameters was investigated as well.Results show that there is a temperature dependence in solubility parameter, which increases by decreasing temperature. However, there were no specific dependence between interaction parameters and temperature, but chemical structure appeared to have a significant effect on them as well as on the type and strength of intermolecular interactions between DL-limonene and investigated solvents. The solubility parameter δ2 of DL-limonene determined to be 19.20 (J/cm3)0.5 at 25°C.

Resolution of limonene 1,2-epoxide diastereomers by mercury(II) ions

NARCIS (Netherlands)

Werf, M. van der; Jongejan, H.; Franssen, M.C.R.

2001-01-01

When HgCl2 was added to a diastereomeric mixture of cis- and trans-(4S)-limonene 1,2-epoxide, the Hg(II) ions stereoselectively complexed to the cis epoxide, enabling ring opening by water. The resulting mercuric salt could be demetalated by treatment with NaBH4, giving a mixture of diastereomeric

Oxidative degradation of toluene and limonene in air by pulsed corona technology

NARCIS (Netherlands)

Hoeben, W.F.L.M.; Beckers, F.J.C.M.; Pemen, A.J.M.; Heesch, van E.J.M.; Kling, W.L.

2012-01-01

The oxidative degradation of two volatile organic compounds, i.e. toluene (fossil fuel based VOC) and limonene (biogenic VOC), has been studied. A hybrid pulsed power corona reactor with adjustable energy density has been utilized for degradation of ppm level target compounds in large air flows. The

Monoterpene engineering in a woody plant Eucalyptus camaldulensis using a limonene synthase cDNA.

Science.gov (United States)

Ohara, Kazuaki; Matsunaga, Etsuko; Nanto, Kazuya; Yamamoto, Kyoko; Sasaki, Kanako; Ebinuma, Hiroyasu; Yazaki, Kazufumi

2010-01-01

Metabolic engineering aimed at monoterpene production has become an intensive research topic in recent years, although most studies have been limited to herbal plants including model plants such as Arabidopsis. The genus Eucalyptus includes commercially important woody plants in terms of essential oil production and the pulp industry. This study attempted to modify the production of monoterpenes, which are major components of Eucalyptus essential oil, by introducing two expression constructs containing Perilla frutescens limonene synthase (PFLS) cDNA, whose gene products were designed to be localized in either the plastid or cytosol, into Eucalyptus camaldulensis. The expression of the plastid-type and cytosol-type PFLS cDNA in transgenic E. camaldulensis was confirmed by real-time polymerase chain reaction (PCR). Gas chromatography with a flame ionization detector analyses of leaf extracts revealed that the plastidic and cytosolic expression of PFLS yielded 2.6- and 4.5-times more limonene than that accumulated in wild-type E. camaldulensis, respectively, while the ectopic expression of PFLS had only a small effect on the emission of limonene from the leaves of E. camaldulensis. Surprisingly, the high level of PFLS in Eucalyptus was accompanied by a synergistic increase in the production of 1,8-cineole and alpha-pinene, two major components of Eucalyptus monoterpenes. This genetic engineering of monoterpenes demonstrated a new potential for molecular breeding in woody plants.

The Optical Properties of Limonene Secondary Organic Aerosols: The Role of NO3, OH, and O3 in the Oxidation Processes

Science.gov (United States)

Peng, Chao; Wang, Weigang; Li, Kun; Li, Junling; Zhou, Li; Wang, Lingshu; Ge, Maofa

2018-03-01

Limonene, a typical proxy of monoterpenes emitted from biogenic sources, plays an important role in secondary organic aerosol (SOA) formation. However, the optical properties of SOA generated from limonene under various oxidation pathways remain poorly understood. In this study, we investigate the refractive index (RI) of limonene SOA produced from four oxidation conditions with cavity ring-down spectrometer (CRDS) and photoacoustic extinctiometer operated at 532 and 375 nm. Our results show that there is a significant difference in RI values of SOA produced from NO3 oxidation compared to other oxidation pathways. The mean values of RI of SOA produced from NO3 oxidation, NOx oxidation, OH oxidation with NOx-free, and O3 oxidation experiments are 1.578, 1.469, 1.495, and 1.494 at 532 nm; and 1.591, 1.527, 1.513, and 1.537 at 375 nm, respectively, while no detectable absorption is found in all oxidation conditions. We attribute the high RI values of SOA by NO3 oxidation to two factors: a large proportion of organic nitrates and high-molecular-weight dimers/oligomers in the SOA. Our study results indicate that the nighttime chemistry may significantly influence the optical properties of limonene oxidation products. The RI values of limonene SOA generated under various oxidation conditions at different wavelengths retrieved in our laboratory experiments could help improve the model predictions for evaluating the effect of biogenic SOA on the global radiative forcing as well as climate change.

Visualization of candidate division OP3 cocci in limonene-degrading methanogenic cultures

DEFF Research Database (Denmark)

Rotaru, Amelia-Elena; Schauer, Regina; Probian, Christina

2012-01-01

Members of candidate division OP3 were detected in 16S rRNA gene clone libraries from methanogenic enrichment cultures that utilized limonene as a carbon and energy source. We developed probes for the visualization of OP3 cells. In situ hybridization experiments with newly designed OP3-specific...

Physicochemical impact of zeolites as the support for photocatalytic hydrogen production using solar-activated TiO2-based nanoparticles

International Nuclear Information System (INIS)

Taheri Najafabadi, Amin; Taghipour, Fariborz

2014-01-01

Highlights: • Zeolite chemical properties are crucial to photocatalytic hydrogen production. • Basic zeolite, TiO 2 , heteropolyacid and cobalt together are active under visible light. • TiO 2 impregnation on zeolite causes band gap widening and band edges’ anodic shift. • Heteropolyacid enhances the visible light activity of the photocatalyst. • Zeolite’s basicity can overshadow the anodic shift, advancing hydrogen evolution. - Abstract: Silico-aluminates (zeolites) have been recently utilized promisingly as the support for photocatalytic hydrogen production using solar-activated TiO 2 -based nanoparticles. Aside from conventional advantages offered by the supports in photocatalysis, we demonstrate the unique physicochemical impact of zeolites on photocatalytic hydrogen production. Beside zeolites, our synthesized materials comprise titanium dioxide (TiO 2 ) as the semiconductor, cobalt ions as the hydrogen evolution sites, and heteropolyacids (HPAs) as the multifunctional solid acids with significant excitability under visible light. Four classes of zeolites (Na-Y, Na-mordenite, H-Y, and H-beta) with different Si/Al ratios and sodium contents were evaluated. Among the studied photocatalysts, Na-Y and Na-mordenite containing 10 wt% titania emerged as the potential candidates for the hydrogen evolution reaction, with corresponding rates of 250.8 and 187.2 μmol/g h, in comparison to 84.2 μmol/g h for Degussa P25; while these values for H-Y and H-beta were 96.8 and 100.1 μmol/g h, respectively. The higher photocatalytic activity of the first two classes is attributed to the basicity of the zeolite matrix, which is possibly due to the pH dependency of the TiO 2 band edges. The results indicate the importance of controlling the chemical properties of the zeolite as a photocatalyst support through the selection of suitable types. Furthermore, our analyses show that the precise pore size distribution of the zeolite framework rules over accommodating the

Ozone and limonene in indoor air: a source of submicron particle exposure.

Science.gov (United States)

Wainman, T; Zhang, J; Weschler, C J; Lioy, P J

2000-12-01

Little information currently exists regarding the occurrence of secondary organic aerosol formation in indoor air. Smog chamber studies have demonstrated that high aerosol yields result from the reaction of ozone with terpenes, both of which commonly occur in indoor air. However, smog chambers are typically static systems, whereas indoor environments are dynamic. We conducted a series of experiments to investigate the potential for secondary aerosol in indoor air as a result of the reaction of ozone with d-limonene, a compound commonly used in air fresheners. A dynamic chamber design was used in which a smaller chamber was nested inside a larger one, with air exchange occurring between the two. The inner chamber was used to represent a model indoor environment and was operated at an air exchange rate below 1 exchange/hr, while the outer chamber was operated at a high air exchange rate of approximately 45 exchanges/hr. Limonene was introduced into the inner chamber either by the evaporation of reagent-grade d-limonene or by inserting a lemon-scented, solid air freshener. A series of ozone injections were made into the inner chamber during the course of each experiment, and an optical particle counter was used to measure the particle concentration. Measurable particle formation and growth occurred almost exclusively in the 0.1-0.2 microm and 0.2-0.3 microm size fractions in all of the experiments. Particle formation in the 0.1-0.2 microm size range occurred as soon as ozone was introduced, but the formation of particles in the 0.2-0.3 microm size range did not occur until at least the second ozone injection occurred. The results of this study show a clear potential for significant particle concentrations to be produced in indoor environments as a result of secondary particle formation via the ozone-limonene reaction. Because people spend the majority of their time indoors, secondary particles formed in indoor environments may make a significant contribution to

Green Synthesis of Carvenone by Montmorillonite-Catalyzed Isomerization of 1,2-Limonene Oxide

DEFF Research Database (Denmark)

Nguyen, Thao-Tran Thi; Chau, Duy-Khiem Nguyen; Duus, Fritz

2013-01-01

Montmorillonite was considered as a good heterogeneous catalyst for the isomerization of 1,2-limonene oxide into car-venone under solvent-free condition. Both conventional heating and green activations were tested in this research. The microwave-assisted isomerization afforded carvenone in high...

Tissue-specific production of limonene in Camelina sativa with the Arabidopsis promoters of genes BANYULS and FRUITFULL.

Science.gov (United States)

Borghi, Monica; Xie, De-Yu

2016-02-01

Arabidopsis promoters of genes BANYULS and FRUITFULL are transcribed in Camelina. They triggered the transcription of limonene synthase and induced higher limonene production in seeds and fruits than CaMV 35S promoter. Camelina sativa (Camelina) is an oilseed crop of relevance for the production of biofuels and the plant has been target of a recent and intense program of genetic manipulation aimed to increase performance, seed yield and to modify the fatty acid composition of the oil. Here, we have explored the performance of two Arabidopsis thaliana (Arabidopsis) promoters in triggering transgene expression in Camelina. The promoters of two genes BANYULS (AtBAN pro ) and FRUITFULL (AtFUL pro ), which are expressed in seed coat and valves of Arabidopsis, respectively, have been chosen to induce the expression of limonene synthase (LS) from Citrus limon. In addition, the constitutive CaMV 35S promoter was utilized to overexpress LS in Camelina . The results of experiments revealed that AtBAN pro and AtFUL pro are actively transcribed in Camelina where they also retain specificity of expression in seeds and valves as previously observed in Arabidopsis. LS induced by AtBAN pro and AtFUL pro leads to higher limonene production in seeds and fruits than when the CaMV 35S was used to trigger the expression. In conclusion, the results of experiments indicate that AtBAN pro and AtFUL pro can be successfully utilized to induce the expression of the transgenes of interest in seeds and fruits of Camelina.

Thermal degradation of terpenes: camphene, Δ-carene, limonene, and α -terpinene

Science.gov (United States)

Gerald W. McGraw; Richard W. Hemingway; Leonard L. Ingram; Catherine S. Canady; William B. McGraw

1999-01-01

Emissions from wood dryers have been of some concern for a number of years, and recent policy changes by the Environmental Protection Agency have placed emphasis upon the gaseous emissions that lead to the formation of particulate matter as small as 2.5 l m diameter. In this qualitative study, camphene, D 3 -carene, limonene, and a -terpinene were thermally degraded in...

Effect of Metarhizium anisopliae (Ascomycete), Cypermethrin, and D-Limonene, Alone and Combined, on Larval Mortality of Rhipicephalus sanguineus (Acari: Ixodidae).

Science.gov (United States)

Prado-Rebolledo, Omar Francisco; Molina-Ochoa, Jaime; Lezama-Gutiérrez, Roberto; García-Márquez, Luis Jorge; Minchaca-Llerenas, Yureida B; Morales-Barrera, Eduardo; Tellez, Guillermo; Hargis, Billy; Skoda, Steven R; Foster, John E

2017-09-01

The effect of the fungus Metarhizium anisopliae Ma14 strain, D-limonene, and cypermethrin, alone and combined, on the mortality of Rhipicephalus sanguineus Latreille larvae was evaluated. Eight separate groups with 25 tick larvae were inoculated with the fungus, cypermethrin, and D-limonene, and four groups were used as untreated controls. The groups were inoculated with serial dilutions of each treatment material: for example, conidial concentrations were 1 × 101, 1 × 102, 1 × 103, 1 × 104, 1 × 105, 1 × 106, 1 × 107, and 1 × 108. A complete randomized experimental design was used. Significant differences were obtained between fungal concentrations, with larval mortalities ranging from 29 to 100%; the D-limonene concentrations showed significant differences, with mortalities that ranged from 47.9 to 82.6%, and cypermethrin mortalities ranged from 69.9 to 89.9% when each was applied alone. In the combined application, the serial dilution of the Ma14 fungus plus cypermethrin at 0.1% concentration caused mortalities ranging from 92.9 to 100%; the mix of serially diluted Ma14 plus D-limonene at 0.1% caused mortalities from 10.3 to 100%; and the mix consisting of serially diluted D-limonene plus cypermethrin at 0.1% caused mortalities from 7.4 to 35.9%. Further laboratory and field research could show that these materials, alone and in combinations, are useful in future tick management and control programs. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Contribution of microwaves or ultrasonics on carvone and limonene recovery from dill fruits

NARCIS (Netherlands)

Esveld, D.C.; Chemat, S.

2013-01-01

The objective of this study is to investigate alternative preparation techniques such as microwave and ultrasound
for the recovery and evaluation of carvone and limonene from flaked dill fruits (Anethum graveolens L.).
The study indicates that microwave-assisted extraction using hexane is

The rice terpene synthase gene OsTPS19 functions as an (S)-limonene synthase in planta, and its overexpression leads to enhanced resistance to the blast fungus Magnaporthe oryzae.

Science.gov (United States)

Chen, Xujun; Chen, Hao; Yuan, Joshua S; Köllner, Tobias G; Chen, Yuying; Guo, Yufen; Zhuang, Xiaofeng; Chen, Xinlu; Zhang, Yong-Jun; Fu, Jianyu; Nebenführ, Andreas; Guo, Zejian; Chen, Feng

2018-03-06

Rice blast disease, caused by the fungus Magnaporthe oryzae, is the most devastating disease of rice. In our ongoing characterization of the defence mechanisms of rice plants against M. oryzae, a terpene synthase gene OsTPS19 was identified as a candidate defence gene. Here, we report the functional characterization of OsTPS19, which is up-regulated by M. oryzae infection. Overexpression of OsTPS19 in rice plants enhanced resistance against M. oryzae, while OsTPS19 RNAi lines were more susceptible to the pathogen. Metabolic analysis revealed that the production of a monoterpene (S)-limonene was increased and decreased in OsTPS19 overexpression and RNAi lines, respectively, suggesting that OsTPS19 functions as a limonene synthase in planta. This notion was further supported by in vitro enzyme assays with recombinant OsTPS19, in which OsTPS19 had both sesquiterpene activity and monoterpene synthase activity, with limonene as a major product. Furthermore, in a subcellular localization experiment, OsTPS19 was localized in plastids. OsTPS19 has a highly homologous paralog, OsTPS20, which likely resulted from a recent gene duplication event. We found that the variation in OsTPS19 and OsTPS20 enzyme activities was determined by a single amino acid in the active site cavity. The expression of OsTPS20 was not affected by M. oryzae infection. This indicates functional divergence of OsTPS19 and OsTPS20. Lastly, (S)-limonene inhibited the germination of M. oryzae spores in vitro. OsTPS19 was determined to function as an (S)-limonene synthase in rice and plays a role in defence against M. oryzae, at least partly, by inhibiting spore germination. © 2018 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

Assessment of different pre-treatment methods for the removal of limonene in citrus waste and their effect on methane potential and methane production rate.

Science.gov (United States)

Ruiz, Begoña; de Benito, Amparo; Rivera, José Daniel; Flotats, Xavier

2016-12-01

The objective of this study was to assess the limonene removal efficiency of three pre-treatment methods when applied to citrus waste and to evaluate their effects on the biochemical methane potential and the methane production rate using batch anaerobic tests. The methods tested were based on removal (biological pretreatment by fungi) or recovery (steam distillation and ethanol extraction) of limonene. All the treatments decreased the concentration of limonene in orange peel, with average efficiencies of 22%, 44% and 100% for the biological treatment, steam distillation and ethanol extraction, respectively. By-products from limonene biodegradation by fungi exhibited an inhibitory effect also, not making interesting the biological pretreatment. The methane potential and production rate of the treated orange peel increased significantly after applying the recovery strategies, which separated and recovered simultaneously other inhibitory components of the citrus essential oil. Apart from the high recovery efficiency of the ethanol extraction process, it presented a favourable energy balance. © The Author(s) 2016.

Research on choleretic effect of menthol, menthone, pluegone, isomenthone, and limonene in DanShu capsule.

Science.gov (United States)

Hu, Guanying; Yuan, Xing; Zhang, Sanyin; Wang, Ruru; Yang, Miao; Wu, Chunjie; Wu, Zhigang; Ke, Xiao

2015-02-01

Danshu capsule (DSC) is a medicinal compound in traditional Chinese medicine (TCM). It is commonly used for the treatment of acute & chronic cholecystitis as well as choleithiasis. To study its choleretic effect, healthy rats were randomly divided into DSC high (DSCH, 900mg/kg), medium (DSCM, 450mg/kg), and low (DSCL, 225mg/kg) group, Xiaoyan Lidan tablet (XYLDT, 750mg/kg), and saline group. The bile was collected for 1h after 20-minute stabilization as the base level, and at 1h, 2h, 3h, and 4h after drug administration, respectively. Bile volume, total cholesterol, and total bile acid were measured at each time point. The results revealed that DSC significantly stimulated bile secretion, decreased total cholesterol level and increased total bile acid level. Therefore, it had choleretic effects. To identify the active components contributing to its choleretic effects, five major constituents which are menthol (39.33mg/kg), menthone (18.02mg/kg), isomenthone (8.18mg/kg), pluegone (3.31mg/kg), and limonene (4.39mg/kg) were tested on our rat model. The results showed that menthol and limonene could promote bile secretion when compared to DSC treatment (p > 0.05); Menthol, menthol and limonene could significantly decrease total cholesterol level (plimonene. Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.

A Role for 2-Methyl Pyrrole in the Browning of 4-Oxopentanal and Limonene Secondary Organic Aerosol

Energy Technology Data Exchange (ETDEWEB)

Aiona, Paige K. [Department; Lee, Hyun Ji [Department; Lin, Peng [Department; Heller, Forrest [Environmental; Laskin, Alexander [Department; Laskin, Julia [Department; Nizkorodov, Sergey A. [Department

2017-09-15

“Brown Carbon” (BrC) is a type of organic particulate matter that absorbs visible and near ultraviolet radiation. Reactions of carbonyls in secondary organic aerosol (SOA) produced from limonene with ammonia (NH3) or ammonium sulfate (AS) are known to produce BrC with a distinctive absorption band at 500 nm. Although the general mechanism for this process has been proposed in previous studies, the specific molecular structures of the light-absorbing species remain unclear. This study examined the browning processes occurring in aqueous solutions of AS and 4-oxopentanal (4-OPA), which has a 1,4-dicarbonyl structural motif present in many limonene SOA compounds. The reaction of 4-OPA with AS in a bulk aqueous solution produces a 2-methyl pyrrole (2-MP) intermediate, which is not a strong light absorber by itself, but can react further with carbonyl compounds leading to the eventual formation of BrC chromophores. The direct involvement of 2-MP in the browning process was demonstrated by reacting 2-MP with 4-OPA and with limonene SOA, both of which produced BrC chromophores with distinctive absorption bands at visible wavelengths. The formation of BrC in reaction of 4-OPA with AS and ammonium nitrate (AN) was found to be accelerated by evaporation of the solution suggesting an important role of the dehydration processes in BrC formation from 1,4- dicarbonyls. 4-OPA was also found to produce BrC in aqueous reactions with a broad spectrum of amino acids and amines. The results suggest that 4-OPA may be the smallest atmospherically relevant compound capable of browning by the same mechanism as limonene SOA.

Pondering the monoterpene composition of Pinus serotina Michx.: can limonene be used as a chemotaxonomic marker for the identification of old turpentine stumps?

Science.gov (United States)

Thomas L. Eberhardt; Jolie M. Mahfouz; Philip M. Sheridan

2010-01-01

Wood samples from old turpentine stumps in Virginia were analyzed by GC-MS to determine if the monoterpene compositions could be used for species identification. Given that limonene is reported to be the predominant monoterpene for pond pine (Pinus serotina Michx.), low relative proportions of limonene in these samples appeared to suggest that these...

Photodegradation of secondary organic aerosol generated from limonene oxidation by ozone studied with chemical ionization mass spectrometry

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X. Pan

2009-06-01

Full Text Available Photodegradation of secondary organic aerosol (SOA prepared by ozone-initiated oxidation of D-limonene is studied with an action spectroscopy approach, which relies on detection of volatile photoproducts with chemical ionization mass-spectrometry as a function of the UV irradiation wavelength. Efficient photodegradation is observed for a broad range of ozone (0.1–300 ppm and D-limonene (0.02–3 ppm concentrations used in the preparation of SOA. The observed photoproducts are dominated by oxygenated C1-C3 compounds such as methanol, formic acid, acetaldehyde, acetic acid, and acetone. The irradiation wavelength dependence of the combined yield of the photoproducts closely tracks the absorption spectrum of the SOA material suggesting that photodegradation is not limited to the UV wavelengths. Kinetic simulations suggest that RO₂+HO₂/RO₂ reactions represent the dominant route to photochemically active carbonyl and peroxide species in the limonene SOA prepared in these experiments. Similar photodegradation processes are likely to occur in realistic SOA produced by OH- or O₃-initiated oxidation of biogenic volatile organic compounds in clean air.

Seasonal Terpene Variation in Needles of Pinus radiata (Pinales: Pinaceae) Trees Attacked by Tomicus piniperda (Coleoptera: Scolytinae) and the Effect of Limonene on Beetle Aggregation.

Science.gov (United States)

Romón, Pedro; Aparicio, Domitila; Palacios, Francisco; Iturrondobeitia, Juan Carlos; Hance, Thierry; Goldarazena, Arturo

2017-09-01

Concentrations of four monoterpenes were determined in needles of Pinus radiata (D.Don) (Pinales: Pinaceae) trees that were attacked or nonattacked by Tomicus piniperda (L.) (Coleoptera: Scolytinae). Compounds were identified and quantified by gas chromatography-mass spectrometry. The mean ambient temperature was obtained using climate-recording data loggers. The effect of limonene on field aggregation was also evaluated at three limonene release rates using Lindgren attractant-baited traps and trap logs. Attacked trees produced less α-pinene in March, July, and November than nonattacked trees, less β-pinene in July and November, and less limonene from May to November. Limonene reduced the attraction of T. piniperda to attractant-baited traps and trap logs. Results were linked to better responses to high temperatures, with respect to terpene contents, by the nonattacked trees after the spring attack. © The Author 2017. Published by Oxford University Press on behalf of Entomological Society of America.

Comparison of the Acidity of Heteropolyacids Encapsulated in or Impregnated on SBA-15

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Pinto Teresa

2016-03-01

Full Text Available Heteropolyacids (HPA immobilized onto SBA-15 silica were prepared by two different ways using either impregnation or encapsulation methodologies. Two Keggin-type HPA, H3PW12O40 and H4SiW12O40 were considered in this study. The resulting hybrid materials were fully characterized by N2 adsorption-desorption isotherms, XRD, FT-IR, Raman, diffuse reflectance UV-Vis spectroscopies and 31P MAS NMR. All characterization methods showed that at room temperature the catalysts contained well-dispersed and intact Keggin units throughout the solid. The catalytic activity of these solids was investigated in the isomerization of n-hexane. The impregnated and encapsulated phosphotungstic catalysts performed similarly in catalysis showing that the amount of active sites was nearly the same in both catalysts. On the contrary, the tungstosilicic encapsulated material was completely inactive while its impregnated counterpart was even more active than the phosphotungstic derived catalysts. The acidity of the solids was measured by various methods: microcalorimetry of ammonia adsorption, ammonia desorption followed by Temperature Programmed Desorption (TPD and DRIFT/GC-MS and pyridine adsorption followed by infrared spectroscopy. Only pyridine adsorption and ammonia desorption followed by DRIFT/GC-MS agreed with the catalytic data. Ammonia adsorption followed by microcalorimetry was not able to differentiate between the four catalysts while the TPD experiments led to unreliable results, as not only the evolved ammonia but also other molecules such as water were taken into account in the measurements. The behavior difference between the encapsulated silico- and phosphotungstic acids was explained by a more pronounced encapsulation in the case of silicon.

Life cycle greenhouse gas impacts of ethanol, biomethane and limonene production from citrus waste

Science.gov (United States)

Pourbafrani, Mohammad; McKechnie, Jon; MacLean, Heather L.; Saville, Bradley A.

2013-03-01

The production of biofuel from cellulosic residues can have both environmental and financial benefits. A particular benefit is that it can alleviate competition for land conventionally used for food and feed production. In this research, we investigate greenhouse gas (GHG) emissions associated with the production of ethanol, biomethane, limonene and digestate from citrus waste, a byproduct of the citrus processing industry. The study represents the first life cycle-based evaluations of citrus waste biorefineries. Two biorefinery configurations are studied—a large biorefinery that converts citrus waste into ethanol, biomethane, limonene and digestate, and a small biorefinery that converts citrus waste into biomethane, limonene and digestate. Ethanol is assumed to be used as E85, displacing gasoline as a light-duty vehicle fuel; biomethane displaces natural gas for electricity generation, limonene displaces acetone in solvents, and digestate from the anaerobic digestion process displaces synthetic fertilizer. System expansion and two allocation methods (energy, market value) are considered to determine emissions of co-products. Considerable GHG reductions would be achieved by producing and utilizing the citrus waste-based products in place of the petroleum-based or other non-renewable products. For the large biorefinery, ethanol used as E85 in light-duty vehicles results in a 134% reduction in GHG emissions compared to gasoline-fueled vehicles when applying a system expansion approach. For the small biorefinery, when electricity is generated from biomethane rather than natural gas, GHG emissions are reduced by 77% when applying system expansion. The life cycle GHG emissions vary substantially depending upon biomethane leakage rate, feedstock GHG emissions and the method to determine emissions assigned to co-products. Among the process design parameters, the biomethane leakage rate is critical, and the ethanol produced in the large biorefinery would not meet EISA�

Life cycle greenhouse gas impacts of ethanol, biomethane and limonene production from citrus waste

International Nuclear Information System (INIS)

Pourbafrani, Mohammad; MacLean, Heather L; Saville, Bradley A; McKechnie, Jon

2013-01-01

The production of biofuel from cellulosic residues can have both environmental and financial benefits. A particular benefit is that it can alleviate competition for land conventionally used for food and feed production. In this research, we investigate greenhouse gas (GHG) emissions associated with the production of ethanol, biomethane, limonene and digestate from citrus waste, a byproduct of the citrus processing industry. The study represents the first life cycle-based evaluations of citrus waste biorefineries. Two biorefinery configurations are studied—a large biorefinery that converts citrus waste into ethanol, biomethane, limonene and digestate, and a small biorefinery that converts citrus waste into biomethane, limonene and digestate. Ethanol is assumed to be used as E85, displacing gasoline as a light-duty vehicle fuel; biomethane displaces natural gas for electricity generation, limonene displaces acetone in solvents, and digestate from the anaerobic digestion process displaces synthetic fertilizer. System expansion and two allocation methods (energy, market value) are considered to determine emissions of co-products. Considerable GHG reductions would be achieved by producing and utilizing the citrus waste-based products in place of the petroleum-based or other non-renewable products. For the large biorefinery, ethanol used as E85 in light-duty vehicles results in a 134% reduction in GHG emissions compared to gasoline-fueled vehicles when applying a system expansion approach. For the small biorefinery, when electricity is generated from biomethane rather than natural gas, GHG emissions are reduced by 77% when applying system expansion. The life cycle GHG emissions vary substantially depending upon biomethane leakage rate, feedstock GHG emissions and the method to determine emissions assigned to co-products. Among the process design parameters, the biomethane leakage rate is critical, and the ethanol produced in the large biorefinery would not meet EISA�

Estabilidade de emulsões de d-limoneno em quitosana modificada Stability of d-limonene emulsions in modified chitosan

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Camila Figueiredo Borgognoni

2006-09-01

Full Text Available A quitosana é um biopolímero produzido a partir da quitina, presente na casca de crustáceos. Atualmente, o estudo de suas propriedades se deve às suas diversas utilizações nas áreas farmacêutica e alimentícia. A quitosana utilizada neste estudo foi quimicamente modificada para tornar-se solúvel em água (quitosana succinilada. Estudou-se a estabilidade de emulsões com d-limoneno para que estes dados sejam úteis na sua posterior utilização como agente de encapsulação de d-limoneno por liofilização. Sua estabilidade foi analisada por espectrofotometria, em diferentes temperaturas, e por cromatografia gasosa associada à técnica da análise do espaço livre, à temperatura ambiente. Sua caracterização foi feita por microscopia óptica. Emulsões de maltodextrina com d-limoneno foram utilizadas para comparação já que maltodextrinas são muito usadas como agentes de encapsulação de aromas. Observou-se boa estabilidade de emulsões de quitosana succinilada com d-limoneno ao longo do tempo e características muito distintas em relação às observadas em emulsões de maltodextrina com d-limoneno. Pode-se concluir neste estudo que emulsões de quitosana succinilada com d-limoneno apresentaram características favoráveis à encapsulação de aromas.Chitosan is a biopolymer derived from chitin, a component of the shells of crustaceans. Recently, special attention has been given to the study of chitosan properties as a consequence of their wide application in pharmaceutical and food areas. In this study, the chitosan used was chemically modified in order to become water soluble (succinyl chitosan. The stability of succinyl chitosan emulsion with d-limonene was studied so that these results could be useful in a subsequent use of succinyl chitosan as a d-limonene encapsulating agent by lyophilization. The stability of the emulsion was analyzed using a spectrophotometer in different temperatures and by the headspace

Comparison of conventional and ultrasound-assisted extraction of carvone and limonene from caraway seeds

NARCIS (Netherlands)

Chemat, S.; Lagha, A.; AitAmar, H.; Bartels, P.V.; Chemat, F.

2004-01-01

Extraction experiments with hexane were carried out at atmospheric pressure in Soxhlet, conventional and ultrasound extractions of flaked caraway seeds, and detailed results are given for two major plant extract components, carvone and limonene. The results indicate that carvone yield and plant

Tailoring the Synergistic Bronsted-Lewis acidic effects in Heteropolyacid catalysts: Applied in Esterification and Transesterification Reactions.

Science.gov (United States)

Tao, Meilin; Xue, Lifang; Sun, Zhong; Wang, Shengtian; Wang, Xiaohong; Shi, Junyou

2015-09-16

In order to investigate the influences of Lewis metals on acidic properties and catalytic activities, a series of Keggin heteropolyacid (HPA) catalysts, HnPW11MO39 (M = Ti(IV), Cu(II), Al(III), Sn(IV), Fe(III), Cr(III), Zr(IV) and Zn(II); for Ti and Zr, the number of oxygen is 40), were prepared and applied in the esterification and transesterification reactions. Only those cations with moderate Lewis acidity had a higher impact. Ti Substituted HPA, H5PW11TiO40, posse lower acid content compared with Ti(x)H(3-4x)PW12O40 (Ti partial exchanged protons in saturated H3PW12O40), which demonstrated that the Lewis metal as an addenda atom (H5PW11TiO40) was less efficient than those as counter cations (Ti(x)H(3-4x)PW12O40). On the other hand, the highest conversion reached 92.2% in transesterification and 97.4% in esterification. Meanwhile, a good result was achieved by H5PW11TiO40 in which the total selectivity of DAG and TGA was 96.7%. In addition, calcination treatment to H5PW11TiO40 make it insoluble in water which resulted in a heterogeneous catalyst feasible for reuse.

Continuous multistep synthesis of perillic acid from limonene by catalytic biofilms under segmented flow.

Science.gov (United States)

Willrodt, Christian; Halan, Babu; Karthaus, Lisa; Rehdorf, Jessica; Julsing, Mattijs K; Buehler, Katja; Schmid, Andreas

2017-02-01

The efficiency of biocatalytic reactions involving industrially interesting reactants is often constrained by toxification of the applied biocatalyst. Here, we evaluated the combination of biologically and technologically inspired strategies to overcome toxicity-related issues during the multistep oxyfunctionalization of (R)-(+)-limonene to (R)-(+)-perillic acid. Pseudomonas putida GS1 catalyzing selective limonene oxidation via the p-cymene degradation pathway and recombinant Pseudomonas taiwanensis VLB120 were evaluated for continuous perillic acid production. A tubular segmented-flow biofilm reactor was used in order to relieve oxygen limitations and to enable membrane mediated substrate supply as well as efficient in situ product removal. Both P. putida GS1 and P. taiwanensis VLB120 developed a catalytic biofilm in this system. The productivity of wild-type P. putida GS1 encoding the enzymes for limonene bioconversion was highly dependent on the carbon source and reached 34 g L tube -1  day -1 when glycerol was supplied. More than 10-fold lower productivities were reached irrespective of the applied carbon source when the recombinant P. taiwanensis VLB120 harboring p-cymene monooxygenase and p-cumic alcohol dehydrogenase was used as biocatalyst. The technical applicability for preparative perillic acid synthesis in the applied system was verified by purification of perillic acid from the outlet stream using an anion exchanger resin. This concept enabled the multistep production of perillic acid and which might be transferred to other reactions involving volatile reactants and toxic end-products. Biotechnol. Bioeng. 2017;114: 281-290. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Interference and Mechanism of Dill Seed Essential Oil and Contribution of Carvone and Limonene in Preventing Sclerotinia Rot of Rapeseed

Science.gov (United States)

Huang, Bo; He, Jingsheng; Tian, Jun; Zeng, Hong; Chen, Yuxin; Wang, Youwei

2015-01-01

This study aimed to evaluate the inhibitory effects of dill (Anethum graveolens L.) seed essential oil against Sclerotinia sclerotiorum and its mechanism of action. The antifungal activities of the two main constituents, namely carvone and limonene, were also measured. Mycelial growth and sclerotial germination were thoroughly inhibited by dill seed essential oil at the 1.00 μL/mL under contact condition and 0.125μL/mL air under vapor condition. Carvone also contributed more than limonene in inhibiting the growth of S. sclerotiorum. Carvone and limonene synergistically inhibited the growth of the fungus. In vivo experiments, the essential oil remarkably suppressed S. sclerotiorum, and considerable morphological alterations were observed in the hyphae and sclerotia. Inhibition of ergosterol synthesis, malate dehydrogenase, succinate dehydrogenase activities, and external medium acidification were investigated to elucidate the antifungal mechanism of the essential oil. The seed essential oil of A. graveolens can be extensively used in agriculture for preventing the oilseed crops fungal disease. PMID:26133771

Interference and Mechanism of Dill Seed Essential Oil and Contribution of Carvone and Limonene in Preventing Sclerotinia Rot of Rapeseed.

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Bingxin Ma

Full Text Available This study aimed to evaluate the inhibitory effects of dill (Anethum graveolens L. seed essential oil against Sclerotinia sclerotiorum and its mechanism of action. The antifungal activities of the two main constituents, namely carvone and limonene, were also measured. Mycelial growth and sclerotial germination were thoroughly inhibited by dill seed essential oil at the 1.00 μL/mL under contact condition and 0.125μL/mL air under vapor condition. Carvone also contributed more than limonene in inhibiting the growth of S. sclerotiorum. Carvone and limonene synergistically inhibited the growth of the fungus. In vivo experiments, the essential oil remarkably suppressed S. sclerotiorum, and considerable morphological alterations were observed in the hyphae and sclerotia. Inhibition of ergosterol synthesis, malate dehydrogenase, succinate dehydrogenase activities, and external medium acidification were investigated to elucidate the antifungal mechanism of the essential oil. The seed essential oil of A. graveolens can be extensively used in agriculture for preventing the oilseed crops fungal disease.

Biomethanization of citrus waste: Effect of waste characteristics and of storage on treatability and evaluation of limonene degradation.

Science.gov (United States)

Lotito, Adriana Maria; De Sanctis, Marco; Pastore, Carlo; Di Iaconi, Claudio

2018-06-01

This study proposes the evaluation of the suitability of mesophilic anaerobic digestion as a simple technology for the treatment of the citrus waste produced by small-medium agro-industrial enterprises involved in the transformation of Citrus fruits. Two different stocks of citrus peel waste were used (i.e., fresh and stored citrus peel waste), to evaluate the influence of waste composition (variability in the type of processed Citrus fruits) and of storage (potentially necessary to operate the anaerobic digester continuously over the whole year due to the seasonality of the production) on anaerobic degradation treatability. A thorough characterization of the two waste types has been performed, showing that the fresh one has a higher solid and organic content, and that, in spite of the similar values of oil fraction amounts, the two stocks are significantly different in the composition of essential oils (43% of limonene and 34% of linalyl acetate in the fresh citrus waste and 20% of limonene and 74% of linalyl acetate in the stored citrus waste). Contrarily to what observed in previous studies, anaerobic digestion was successful and no reactor acidification occurred. No inhibition by limonene and linalyl acetate even at the maximum applied organic load value (i.e., 2.72 gCOD waste /gVS inoculum ) was observed in the treatment of the stored waste, with limonene and linalyl acetate concentrations of 104 mg/l and 385 mg/l, respectively. On the contrary, some inhibition was detected with fresh citrus peel waste when the organic load increased from 2.21 to 2.88 gCOD waste /gVS inoculum , ascribable to limonene at initial concentration higher than 150 mg/l. A good conversion into methane was observed with fresh peel waste, up to 0.33  [Formula: see text] at the highest organic load, very close to the maximum theoretical value of 0.35 [Formula: see text] , while a lower efficiency was achieved with stored peel waste, with a reduction down to 0.24  [Formula: see

The oxidation of limonene at raised pressure and over the various titanium-silicate catalysts

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Wróblewska Agnieszka

2015-12-01

Full Text Available This work presents the studies on the oxidation of limonene with hydrogen peroxide and tert-butyl hydroperoxide (TBHP in the presence of : TS-2, Ti-Beta, Ti-MCM-41 and Ti-MWW catalysts, at the autogenic pressure and atmospheric pressure. The examination were performed at the following conditions: the temperature of 140°C (studies in the autoclave and 80°C (studies in glass reactor, the molar ratio of limonene/oxidant (H2O2 or WNTB = 1:1, the methanol concentration 80 wt%, the catalyst content 3 wt%, the reaction time 3 h and the intensity of stirring 500 rpm. The analysis of the results showed that in process not only 1,2-epoxylimonene was formed but also: 1,2-epoxylimonene diol, carveol, carvone and perillyl alcohol but for 1,2-epoxylimonene obtaining the better method was the method at the autogenic pressure and in the presence of TBHP.

Radiation-induced cationic polymerization of limonene oxide, α-pinene oxide, and β-pinene oxide

International Nuclear Information System (INIS)

Aikins, J.A.; Williams, F.

1984-01-01

After suitable drying, the subject monomers in the form of neat liquids undergo radiation-induced polymerization with no apparent side reactions and high conversions to precipitatable polymers of low molecular weight. A cationic mechanism is evidenced by the strongly retarding effect of tri-n-propylamine on the polymerization rate. At 25 0 C, limonene oxide gives the highest polymerization rates, an average conversion of 36% per Mrad being obtained in comparison with values of 5.7 and 7.3% per Mrad for the α-pinene and β-pinene oxides, respectively. Similarly, the average anti DP/sub n/ decreases from 11.8 for the limonene oxide polymer to 5.6 and 4.0 for the α-pinene oxide and β-pinene oxide polymers, respectively. A high frequency of chain transfer to monomer is indicated in each case by the fact that the kinetic chain lengths are estimated to be on the order of a hundred times larger than the anti DP/sub n/ values. Structural characterization of the limonene oxide polymer by 1 H and 13 C NMR spectroscopy provides conclusive evidence that the polymerization proceeds by the opening of the epoxide ring to yield a 1,2-trans polyether. Similar NMR studies on the polymers formed from the α-pinene and β-pinene oxides show that in the polymerization of these monomers, the opening of the epoxide ring is generally accompanied by the concomitant ring opening of the cyclobutane ring structure to yield a gem-dimethyl group in the main chain. The detection of isopropenyl end groups in the pinene oxide polymers is also consistent with this mode of propagation being followed by chain (proton) transfer to monomer

Sulfur‐Limonene Polysulfide: A Material Synthesized Entirely from Industrial By‐Products and Its Use in Removing Toxic Metals from Water and Soil

Science.gov (United States)

Crockett, Michael P.; Evans, Austin M.; Worthington, Max J. H.; Albuquerque, Inês S.; Slattery, Ashley D.; Gibson, Christopher T.; Campbell, Jonathan A.; Lewis, David A.; Bernardes, Gonçalo J. L.

2015-01-01

Abstract A polysulfide material was synthesized by the direct reaction of sulfur and d‐limonene, by‐products of the petroleum and citrus industries, respectively. The resulting material was processed into functional coatings or molded into solid devices for the removal of palladium and mercury salts from water and soil. The binding of mercury(II) to the sulfur‐limonene polysulfide resulted in a color change. These properties motivate application in next‐generation environmental remediation and mercury sensing. PMID:26481099

The effect of inoculation with mycorrhizal arbuscular fungi on expression of limonene synthase in Mentha spicata L. genotypes

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Leila Shabani

2015-03-01

Full Text Available Spearmint (Mentha spicata L. is an important economical and medicinal plant from Lamiaceae family, which has gained research attraction as a model for biosynthesis of essential oils due to its high capability for synthesis of monoterpenes. Limonene is a simple monoterpene and its biosynthesis is catalyzed by limonene synthase a key regulatory enzyme in the biosynthesis pathway of monoterpenes in spearmint plant. This study was concerned with the effect of colonization of roots with Funneliformis mosseae and F. etunicatum fungi on spearmint plant growth indices, leaf essential oils and changes in the expression of limonene synthase (LS gene. This study also explained the application of GADPH gene as the internal standard for real-time quantitative PCR (RTqPCR analysis of LS in spearmints. Our results showed that essential oil content of leaf in spearmint genotype Meybod inoculated with F. etunicatum was higher than that of genotypes from populations Kashan and Bojnourd and was 130% higher than the control. According to the results of this study, increase in transcript accumulation of the LS gene in leaves of spearmint plants inoculated with F. etunicatum was concordant with the increased essential oil contents and was dependent on the plant genotype.

Different Roles of Endo- and Exo-cyclic Double Bonds in Limonene Ozonolysis System: Effect of Water and OH Radical Scavengers

Science.gov (United States)

Gong, Y.; Li, H.; Chen, Z.

2017-12-01

Limonene, as an important monoterpene, has a high emission rate both from biogenic and anthropogenic sources. Its doubly unsaturated structure leads to a high potential for secondary organic aerosol formation and a detailed understanding of roles of endo- and exo-cyclic double bonds in limonene ozonolysis is in urgent need. This study provided new insights into the mechanism and effect of both unsaturated bonds oxidation. A low and a high ratio set of [O3]/[limonene] experiments in the presence or absence of OH scavenger (2-butanol or cyclohexane) in the relative humidity (RH) range of 0-90% were conducted. Molar yields of hydrogen peroxide (H2O2) and hydromethyl hydroperoxide (HMHP) both increased rapidly as RH rose from 0 to 50%, then reached a plateau above 70% RH, while peroxyformic acid (PFA) and peroxyacetic acid (PAA) kept increasing with RH. The ozonolysis of exocyclic double bonds showed larger capacity for producing these peroxides than endocyclic ones, resulting in significantly higher yields of H2O2, HMHP, PFA and PAA in limonene ozonolysis than α-pinene when ozone was sufficient. The SOA mass fraction of total peroxides was 50% at high [O3]/[limonene] ratio, whereas only 12% at low ratio. The gas-particle partitioning coefficient of undetected peroxides rose up from (0.8-2.0)×10-3m3μg-1 at 0% RH to (4.0-5.2)×10-3m3μg-1 at 90% RH, indicating some water-dependent channels contributed low-volatility peroxides formation. A box model was employed to simulate the reaction system, and the results obviously underestimated the yield of H2O2, whilst overestimated the yield of undetected peroxides. It is interesting to note that SOA produced at high [O3]/[limonene] ratio could generate considerable amount of H2O2 in the aqueous phase, which may be another source of H2O2 in cloud drops. To elucidate the mechanism further, the yield of OH radicals formed from endocyclic double bonds was found to be about 3 times larger than that from exocyclic double bonds

Chemoselective alternating copolymerization of limonene dioxide and carbon dioxide : a new highly functional aliphatic epoxy polycarbonate

NARCIS (Netherlands)

Li, C.; Sablong, R.J.; Koning, C.E.

The alternating copolymerization of biorenewable limonene dioxide with carbon dioxide (CO2) catalyzed by a zinc β-diiminate complex is reported. The chemoselective reaction results in linear amorphous polycarbonates that carry pendent methyloxiranes and exhibit glass transition temperatures (Tg) up

Growth-arresting Activity of Acmella Essential Oil and its Isolated Component D-Limonene (1, 8 P-Mentha Diene) against Trichophyton rubrum (Microbial Type Culture Collection 296).

Science.gov (United States)

Padhan, Diptikanta; Pattnaik, Smaranika; Behera, Ajaya Kumar

2017-10-01

Spilanthes acmella is used as a remedy in toothache complaints by the tribal people of Western part of Odisha, India. The objective of this study was to study the growth-arresting activity of an indigenous Acmella essential oil (EO) ( S. acmella Murr, Asteraceae ) and its isolated component, d-limonene against Trichophyton rubrum (microbial type culture collection 296). The EO was extracted from flowers of indigenous S. acmella using Clevenger's apparatus and analyzed by gas chromatography-mass spectrometry (GC-MS). High pressure liquid chromatography (HPLC) was carried out to isolate the major constituent. The isolated fraction was subjected to fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR). The antidermatophytic activity was screened for using "disc diffusion" and "slant dilution" method followed by optical, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) studies. The molecular dockings were made between d-limonene with cell wall synthesis-related key enzymes (14 methyl deaminase and monooxygenase). The GC-MS analysis EO had inferred the presence of 7 number of major (≥2%) components. The component with highest peak area (%) was found to be 41.02. The HPLC-isolated fraction was identified as d-limonene (1,8 p-Mentha-diene) by FTIR and NMR. Qualitative and quantitative assays had suggested the growth inhibitory activity of Acmella EO and its component. Shrinkage, evacuation, cell wall puncture, and leakage of cellular constituents by the activity of Acmella oil and d-limonene were evidenced from optical, SEM, and TEM studies. The computer simulation had predicted the binding strengths of d-limonene and fluconazole with dermatophyte cell wall enzymes. There could have been synergistic action of all or some of compounds present in indigenous Acmella EO. There was presence of seven number of (d-limonene, ocimene, β-myrcene, cyclohexene, 3-(1, 5-dimethyl-4-hexenyl)-6-methylene, �

Mixing Time, Inversion and Multiple Emulsion Formation in a Limonene and Water Pickering Emulsion

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Laura Sawiak

2018-05-01

Full Text Available It has previously been demonstrated that particle-stabilized emulsions comprised of limonene, water and fumed silica particles exhibit complex emulsification behavior as a function of composition and the duration of the emulsification step. Most notably the system can invert from being oil-continuous to being water-continuous under prolonged mixing. Here we investigate this phenomenon experimentally for the regime where water is the majority liquid. We prepare samples using a range of different emulsification times and we examine the final properties in bulk and via confocal microscopy. We use the images to quantitatively track the sizes of droplets and clusters of particles. We find that a dense emulsion of water droplets forms initially which is transformed, in time, into a water-in-oil-in-water multiple emulsion with concomitant changes in droplet and cluster sizes. In parallel we carry out rheological studies of water-in-limonene emulsions using different concentrations of fumed silica particles. We unite our observations to propose a mechanism for inversion based on the changes in flow properties and the availability of particles during emulsification.

Microorganisms screening for limonene oxidation Seleção de microrganismos para oxidação de limoneno

Directory of Open Access Journals (Sweden)

Lindomar Lerin

2010-06-01

Full Text Available Limonene is a monoterpene obtained in large amounts from essential oils and is used as a raw material for the synthesis of flavors and fine chemicals. Several pathways or routes for the microbial degradation of limonene making use of the cytochrome P450-dependent monooxygenases have been described. In this study, we present a fermentative screening of microorganisms in order to verify their ability to perform the desirable conversion. In parallel, the PCR technique was used to select the microorganisms that contain the limC gene, which is responsible for the conversion of carveol to carvone. The microorganisms selected by PCR were not able to bioconvert limonene. From this result, we can suppose that these strains do not have the gene that codifies the enzyme responsible for the transformation of limonene into carveol. The results obtained in the fermentative screening showed that 4 microorganisms were able to bioconvert limonene into carveol. In addition, the amplification results showed the presence of fragments of 800 pb, expected for the limC gene. Therefore, the results obtained in the bioconversion and evaluation of the limC gene did not allow a correlation showing that these strains do not contain all the enzymes responsible for the conversion of limonene to carvone.O limoneno é um monoterpeno obtido em grandes quantidades a partir de óleos essenciais, podendo ser utilizado como matéria-prima na síntese de flavours e compostos para química fina. Várias rotas para a degradação microbiológica do limoneno fazendo uso da monoxigenase dependente do citocromo P450 têm sido propostas. Neste trabalho, são apresentados dados obtidos no screening fermentativo de microrganismos visando verificar suas habilidades em realizar a conversão desejada. Em paralelo, a técnica do PCR foi também utilizada visando selecionar microrganismos que apresentam o gene limC, responsável pela conversão de carveol a carvona. Os microrganismos

Fat and fibre interfere with the dramatic effect that nanoemulsified d-limonene has on the heat resistance of Listeria monocytogenes.

Science.gov (United States)

Maté, Javier; Periago, Paula M; Ros-Chumillas, María; Grullón, Coralin; Huertas, Juan Pablo; Palop, Alfredo

2017-04-01

The application of d-limonene in form of nanoemulsion has been proved to reduce dramatically the thermal resistance of Listeria monocytogenes in culture media. The present research shows very promising results on the application in food products. The thermal resistance of L. monocytogenes was reduced 90 times when 0.5 mM nanoemulsified d-limonene was added to apple juice. This is the biggest reduction in the heat resistance of a microorganism caused by an antimicrobial described ever. However, no effect was found in carrot juice. A carrot juice system was prepared in an attempt to unravel which juice constituents were responsible for the lack of effect. When fat and fibre were not included in the carrot juice system formulation, the thermal resistance of L. monocytogenes was, again, dramatically reduced in presence of nanoemulsified d-limonene, so these components were shown to interfere with the effect. Once this interaction with food constituents becomes solved, the addition of nanoemulsified antimicrobials would allow to reduce greatly the intensity of the thermal treatments currently applied in the food processing industry. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Chitosan-limonene coating in combination with modified atmosphere packaging preserve postharvest quality of cucumber during storage

NARCIS (Netherlands)

Maleki, Gisoo; Sedaghat, Naser; Woltering, Ernst J.; Farhoodi, Mehdi; Mohebbi, Mohebbat

2018-01-01

Since cucumbers suffer from a short postharvest life, applying different technologies is increasingly used as effective ways to increase their shelf life and quality. In this study a combination of chitosan-limonene coating and MAP storage has been used as a postharvest treatment to maintain

Permeation of limonene through disposable nitrile gloves using a dextrous robot hand.

Science.gov (United States)

Banaee, Sean; S Que Hee, Shane

2017-03-28

The purpose of this study was to investigate the permeation of the low-volatile solvent limonene through different disposable, unlined, unsupported, nitrile exam whole gloves (blue, purple, sterling, and lavender, from Kimberly-Clark). This study utilized a moving and static dextrous robot hand as part of a novel dynamic permeation system that allowed sampling at specific times. Quantitation of limonene in samples was based on capillary gas chromatography-mass spectrometry and the internal standard method (4-bromophenol). The average post-permeation thicknesses (before reconditioning) for all gloves for both the moving and static hand were more than 10% of the pre-permeation ones (P≤0.05), although this was not so on reconditioning. The standardized breakthrough times and steady-state permeation periods were similar for the blue, purple, and sterling gloves. Both methods had similar sensitivity. The lavender glove showed a higher permeation rate (0.490±0.031 μg/cm 2 /min) for the moving robotic hand compared to the non-moving hand (P≤0.05), this being ascribed to a thickness threshold. Permeation parameters for the static and dynamic robot hand models indicate that both methods have similar sensitivity in detecting the analyte during permeation and the blue, purple, and sterling gloves behave similarly during the permeation process whether moving or non-moving.

Permeation of limonene through disposable nitrile gloves using a dextrous robot hand

Science.gov (United States)

Banaee, Sean; S Que Hee, Shane

2017-01-01

Objectives: The purpose of this study was to investigate the permeation of the low-volatile solvent limonene through different disposable, unlined, unsupported, nitrile exam whole gloves (blue, purple, sterling, and lavender, from Kimberly-Clark). Methods: This study utilized a moving and static dextrous robot hand as part of a novel dynamic permeation system that allowed sampling at specific times. Quantitation of limonene in samples was based on capillary gas chromatography-mass spectrometry and the internal standard method (4-bromophenol). Results: The average post-permeation thicknesses (before reconditioning) for all gloves for both the moving and static hand were more than 10% of the pre-permeation ones (P≤0.05), although this was not so on reconditioning. The standardized breakthrough times and steady-state permeation periods were similar for the blue, purple, and sterling gloves. Both methods had similar sensitivity. The lavender glove showed a higher permeation rate (0.490±0.031 μg/cm2/min) for the moving robotic hand compared to the non-moving hand (P≤0.05), this being ascribed to a thickness threshold. Conclusions: Permeation parameters for the static and dynamic robot hand models indicate that both methods have similar sensitivity in detecting the analyte during permeation and the blue, purple, and sterling gloves behave similarly during the permeation process whether moving or non-moving. PMID:28111415

Tissue-specific production of limonene in Camelina sativa with the Arabidopsis promoters of genes BANYULS and FRUITFULL

NARCIS (Netherlands)

Borghi, Monica; Xie, De Yu

2016-01-01

Main conclusion: Arabidopsis promoters of genesBANYULSandFRUITFULLare transcribed in Camelina. They triggered the transcription oflimonene synthaseand induced higher limonene production in seeds and fruits thanCaMV 35Spromoter.Camelina sativa (Camelina) is an oilseed crop of relevance for the

Catalytic ring-​opening copolymerization of limonene oxide and phthalic anhydride : toward partially renewable polyesters

NARCIS (Netherlands)

Hosseini Nejad, E.; Pionasari, A; Melis, van C.G.W.; Koning, C.E.; Duchateau, R.

2013-01-01

Catalytic ring-¿opening copolymn. of limonene oxide with phthalic anhydride was performed applying metal t-¿Bu-¿salophen complexes (t-¿Bu-¿salophen)¿MX; M = Cr, X = Cl (1)¿, M = Al, X = Cl (2)¿, M = Co, X = OAc (3)¿, M = Mn, X = Cl (4)¿, t-¿Bu-¿salophen =

Investigating the Heterogeneous Interaction of VOCs with Natural Atmospheric Particles: Adsorption of Limonene and Toluene on Saharan Mineral Dusts.

Science.gov (United States)

Romanías, Manolis N; Ourrad, Habib; Thévenet, Frédéric; Riffault, Véronique

2016-03-03

The heterogeneous interaction of limonene and toluene with Saharan dusts was investigated under dark conditions, pressure of 1 atm, and temperature 293 K. The mineral dust samples were collected from six different regions along the Sahara desert, extending from Tunisia to the western Atlantic coastal areas of Morocco, and experiments were carried out with the smallest sieved fractions, that is, inferior to 100 μm. N2 sorption measurements, granulometric analysis, and X-ray fluorescence and diffraction (XRF and XRD) measurements were conducted to determine the physicochemical properties of the particles. The chemical characterization showed that dust originating from mideastern Sahara has a significantly higher SiO2 content (∼ 82%) than dust collected from the western coastal regions where the SiO2 relative abundance was ∼ 50%. A novel experimental setup combining diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), selected-ion flow-tube mass spectrometry (SIFT-MS), and long path transmission Fourier transform infrared spectroscopy (FTIR) allowed us to follow both the adsorbed and gas phases. The kinetic adsorption/desorption measurements were performed using purified dry air as bath gas, exposing each dust surface to 10 ppm of the selective volatile organic compound (VOC). The adsorption of limonene was independent of the SiO2 content, given the experimental uncertainties, and the coverage measurements ranged between (10 and 18) × 10(13) molecules cm(-2). Experimental results suggest that other metal oxides that could possibly influence dust acidity may enhance the adsorption of limonene. On the contrary, in the case of toluene, the adsorption capacities of the Saharan samples increased with decreasing SiO2 content; however, the coverage measurements were significantly lower than those of limonene and ranged between (2 and 12) × 10(13) molecules cm(-2). Flushing the surface with purified dry air showed that VOC desorption is not a

Physiological and Transcriptional Responses of Saccharomyces cerevisiae to d-Limonene Show Changes to the Cell Wall but Not to the Plasma Membrane

Science.gov (United States)

Brennan, Timothy C. R.; Nielsen, Lars K.

2013-01-01

Monoterpenes can, upon hydrogenation, be used as light-fraction components of sustainable aviation fuels. Fermentative production of monoterpenes in engineered microorganisms, such as Saccharomyces cerevisiae, has gained attention as a potential route to deliver these next-generation fuels from renewable biomass. However, end product toxicity presents a formidable problem for microbial synthesis. Due to their hydrophobicity, monoterpene inhibition has long been attributed to membrane interference, but the molecular mechanism remains largely unsolved. In order to gain a better understanding of the mode of action, we analyzed the composition and structural integrity of the cell envelope as well as the transcriptional response of yeast cells treated with an inhibitory amount of d-limonene (107 mg/liter). We found no alterations in membrane fluidity, structural membrane integrity, or fatty acid composition after the solvent challenge. A 4-fold increase in the mean fluorescence intensity per cell (using calcofluor white stain) and increased sensitivity to cell wall-degrading enzymes demonstrated that limonene disrupts cell wall properties. Global transcript measurements confirmed the membrane integrity observations by showing no upregulation of ergosterol or fatty acid biosynthesis pathways, which are commonly overexpressed in yeast to reinforce membrane rigidity during ethanol exposure. Limonene shock did cause a compensatory response to cell wall damage through overexpression of several genes (ROM1, RLM1, PIR3, CTT1, YGP1, MLP1, PST1, and CWP1) involved with the cell wall integrity signaling pathway. This is the first report demonstrating that cell wall, rather than plasma membrane, deterioration is the main source of monoterpene inhibition. We show that limonene can alter the structure and function of the cell wall, which has a clear effect on cytokinesis. PMID:23542628

Theoretical study of sum-frequency vibrational spectroscopy on limonene surface

International Nuclear Information System (INIS)

Zheng, Ren-Hui; Liu, Hao; Jing, Yuan-Yuan; Wang, Bo-Yang; Shi, Qiang; Wei, Wen-Mei

2014-01-01

By combining molecule dynamics (MD) simulation and quantum chemistry computation, we calculate the surface sum-frequency vibrational spectroscopy (SFVS) of R-limonene molecules at the gas-liquid interface for SSP, PPP, and SPS polarization combinations. The distributions of the Euler angles are obtained using MD simulation, the ψ-distribution is between isotropic and Gaussian. Instead of the MD distributions, different analytical distributions such as the δ-function, Gaussian and isotropic distributions are applied to simulate surface SFVS. We find that different distributions significantly affect the absolute SFVS intensity and also influence on relative SFVS intensity, and the δ-function distribution should be used with caution when the orientation distribution is broad. Furthermore, the reason that the SPS signal is weak in reflected arrangement is discussed

Theoretical study of sum-frequency vibrational spectroscopy on limonene surface

Energy Technology Data Exchange (ETDEWEB)

Zheng, Ren-Hui, E-mail: zrh@iccas.ac.cn; Liu, Hao; Jing, Yuan-Yuan; Wang, Bo-Yang; Shi, Qiang [Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun, Beijing 100190 (China); Wei, Wen-Mei [Department of Chemistry, College of Basic Medicine, Anhui Medical University, Hefei, Anhui 230032 (China)

2014-03-14

By combining molecule dynamics (MD) simulation and quantum chemistry computation, we calculate the surface sum-frequency vibrational spectroscopy (SFVS) of R-limonene molecules at the gas-liquid interface for SSP, PPP, and SPS polarization combinations. The distributions of the Euler angles are obtained using MD simulation, the ψ-distribution is between isotropic and Gaussian. Instead of the MD distributions, different analytical distributions such as the δ-function, Gaussian and isotropic distributions are applied to simulate surface SFVS. We find that different distributions significantly affect the absolute SFVS intensity and also influence on relative SFVS intensity, and the δ-function distribution should be used with caution when the orientation distribution is broad. Furthermore, the reason that the SPS signal is weak in reflected arrangement is discussed.

From waste to value - direct utilization of limonene from orange peel in a biocatalytic cascade reaction towards chiral carvolactone

NARCIS (Netherlands)

Oberleitner, N.; Ressmann, A. K.; Bica, K.; Gaertner, P.; Fraaije, M. W.; Bornscheuer, U. T.; Rudroff, F.; Mihovilovic, M. D.

2017-01-01

In this proof of concept study we demonstrate direct utilization of limonene containing waste product orange peel as starting material for a biocatalytic cascade reaction. The product of this cascade is chiral carvolactone, a promising building block for thermoplastic polymers. Four different

Characterization of organic nitrate constituents of secondary organic aerosol (SOA) from nitrate-radical-initiated oxidation of limonene using high-resolution chemical ionization mass spectrometry

Science.gov (United States)

Faxon, Cameron; Hammes, Julia; Le Breton, Michael; Kant Pathak, Ravi; Hallquist, Mattias

2018-04-01

The gas-phase nitrate radical (NO3⚫) initiated oxidation of limonene can produce organic nitrate species with varying physical properties. Low-volatility products can contribute to secondary organic aerosol (SOA) formation and organic nitrates may serve as a NOx reservoir, which could be especially important in regions with high biogenic emissions. This work presents the measurement results from flow reactor studies on the reaction of NO3⚫ with limonene using a High-Resolution Time-of-Flight Chemical Ionization Mass Spectrometer (HR-ToF-CIMS) combined with a Filter Inlet for Gases and AEROsols (FIGAERO). Major condensed-phase species were compared to those in the Master Chemical Mechanism (MCM) limonene mechanism, and many non-listed species were identified. The volatility properties of the most prevalent organic nitrates in the produced SOA were determined. Analysis of multiple experiments resulted in the identification of several dominant species (including C10H15NO6, C10H17NO6, C8H11NO6, C10H17NO7, and C9H13NO7) that occurred in the SOA under all conditions considered. Additionally, the formation of dimers was consistently observed and these species resided almost completely in the particle phase. The identities of these species are discussed, and formation mechanisms are proposed. Cluster analysis of the desorption temperatures corresponding to the analyzed particle-phase species yielded at least five distinct groupings based on a combination of molecular weight and desorption profile. Overall, the results indicate that the oxidation of limonene by NO3⚫ produces a complex mixture of highly oxygenated monomer and dimer products that contribute to SOA formation.

Characterization of organic nitrate constituents of secondary organic aerosol (SOA from nitrate-radical-initiated oxidation of limonene using high-resolution chemical ionization mass spectrometry

Directory of Open Access Journals (Sweden)

C. Faxon

2018-04-01

Full Text Available The gas-phase nitrate radical (NO3⚫ initiated oxidation of limonene can produce organic nitrate species with varying physical properties. Low-volatility products can contribute to secondary organic aerosol (SOA formation and organic nitrates may serve as a NOx reservoir, which could be especially important in regions with high biogenic emissions. This work presents the measurement results from flow reactor studies on the reaction of NO3⚫ with limonene using a High-Resolution Time-of-Flight Chemical Ionization Mass Spectrometer (HR-ToF-CIMS combined with a Filter Inlet for Gases and AEROsols (FIGAERO. Major condensed-phase species were compared to those in the Master Chemical Mechanism (MCM limonene mechanism, and many non-listed species were identified. The volatility properties of the most prevalent organic nitrates in the produced SOA were determined. Analysis of multiple experiments resulted in the identification of several dominant species (including C10H15NO6, C10H17NO6, C8H11NO6, C10H17NO7, and C9H13NO7 that occurred in the SOA under all conditions considered. Additionally, the formation of dimers was consistently observed and these species resided almost completely in the particle phase. The identities of these species are discussed, and formation mechanisms are proposed. Cluster analysis of the desorption temperatures corresponding to the analyzed particle-phase species yielded at least five distinct groupings based on a combination of molecular weight and desorption profile. Overall, the results indicate that the oxidation of limonene by NO3⚫ produces a complex mixture of highly oxygenated monomer and dimer products that contribute to SOA formation.

Aggregate exposure to common fragrance compounds: Comparison of the contribution of essential oils and cosmetics using probabilistic methods and the example of limonene.

Science.gov (United States)

Dornic, N; Roudot, A C; Batardière, A; Nedelec, A S; Bourgeois, P; Hornez, N; Le Caer, F; Ficheux, A S

2018-04-09

The knowledge of aggregate exposure to different types of products is paramount in the risk assessment. The aim of this study was to compare the relative contribution of essential oils compared to cosmetics on the daily dermal exposure to limonene, an ubiquitous fragrance compound that can be an allergen depending on its degree of oxidation. Aggregate daily exposure to limonene was calculated among a panel of French volunteers using both essential oils and cosmetics, for 4 different specific zones, i.e. face and neck, chest, upper limbs and lower limbs. Calculations were made using a probabilistic Monte Carlo method and sensitivity analysis. The main strength of this work was the inclusion of essential oils in addition to cosmetics in the model. For the first time, the generated data could be used to compare the contribution of these two products in dermal exposure. Essential oils appear to be significant contributors to exposure to limonene particularly for the face. This work is a first step that will permit to determine the exposure to other fragrance compounds with sensitizing potential. These data will be useful for risk managers to consider the inclusion of essential oils in the overall burden of this pathology. Copyright © 2018 Elsevier Ltd. All rights reserved.

Early LC3 lipidation induced by d-limonene does not rely on mTOR inhibition, ERK activation and ROS production and it is associated with reduced clonogenic capacity of SH-SY5Y neuroblastoma cells.

Science.gov (United States)

Berliocchi, Laura; Chiappini, Carlotta; Adornetto, Annagrazia; Gentile, Debora; Cerri, Silvia; Russo, Rossella; Bagetta, Giacinto; Corasaniti, Maria Tiziana

2018-02-01

d-Limonene is a natural monoterpene abundant in Citrus essential oils. It is endowed with several biological activities, including inhibition of carcinogenesis and promotion of tumour regression. Recently, d-limonene has been shown to modulate autophagic markers in vitro at concentrations found in vivo, in clinical pharmacokinetic studies. Autophagy is an intracellular catabolic process serving as both an adaptive metabolic response and a quality control mechanism. Because autophagy defects have been linked to a wide range of human pathologies, including neurodegeneration and cancer, there is a need for new pharmacological tools to control deregulated autophagy. To better understand the effects of d-limonene on autophagy, to identify the molecular mechanisms through which this monoterpene rapidly triggers LC3 lipidation and to evaluate the role for autophagy in long-term effects of d-limonene. Human SH-SY5Y neuroblastoma, HepG2 hepatocellular carcinoma and MCF7 breast cancer cells were used. Endogenous LC3-II levels were evaluated by western blotting. Autophagic flux assay was performed using bafilomycin A1 and chloroquine. Intracellular distribution of LC3 protein was studied by confocal microscopy analysis of LC3B-GFP transduced cells. Expression of lysosomal-membrane protein LAMP-1 was assessed by immunofluorescence analysis. Phosphorylated levels of downstream substrates of mTOR kinase (p70S6 kinase, 4E-BP1, and ULK1) and ERK were analyzed by western blotting. Production of reactive oxygen species (ROS) was assessed by live confocal microscopy of cells loaded with CellROX ® Green Reagent. Clonogenic assay was used to evaluate the ability of treated cells to proliferate and form colonies. LC3 lipidation promoted by d-limonene correlates with autophagosome formation and stimulation of basal autophagy. LC3 lipidation does not rely on inhibition of mTOR kinase, which instead appears to be transiently activated. In addition, d-limonene rapidly activates ERK and

Essential Oils from Seeds: Solubility of Limonene in Supercritical CO2 and How It Is Affected by Fatty Oil

Czech Academy of Sciences Publication Activity Database

Sovová, Helena; Stateva, R. P.; Galushko, A. A.

2001-01-01

Roč. 20, č. 2 (2001), s. 113-129 ISSN 0896-8446 R&D Projects: GA ČR GA203/98/1445 Institutional research plan: CEZ:AV0Z4072921 Keywords : vapour-liquid equilibria * limonene * supercritical carbon dioxide Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 1.975, year: 2001

Synthesis and antiproliferative activity of novel limonene derivatives with a substituted thiourea moiety

International Nuclear Information System (INIS)

Figueiredo, Isis M.; Santos, Luciane V. dos; Costa, Willian F. da; Silva, Cleuza C. da; Sarragiotto, Maria H.; Carvalho, Joao E. de; Sacoman, Juliana L.; Kohn, Luciana K.

2006-01-01

A series of R-(+)-limonene derivatives bearing a substituted thiourea moiety (3-13) and five S-methyl analogs (14-18) were synthesized and evaluated for their in vitro antiproliferative activity against human cancer cell lines. Compounds bearing aromatic substituents (3-6) exhibit cytostatic activity in the full panel of cell lines tested, with GI 50 values in the range of 2.5 to 24 μmol L -1 . Compounds 3, 10, 12 and 16 were the most active with GI 5 )0 values in the range of 0.41 to 3.0 μmol L -1 , against different cell lines. (author)

PMR investigation of configuration and mobility of H5O2+ ions in certain tungsten heteropolyacid hexahydrates

International Nuclear Information System (INIS)

Chuvaev, V.F.; Barash, A.B.

1982-01-01

PMR-method of wide bands has been used to investigate hexahydrates of tungsten typical heteropolyacids (HPA): H 3 PW 12 O 40 x6H 2 O, H 4 SiW 12 O 40 x6H 2 O, H 5 BW 12 O 40 x6H 2 O. The results are considered from the viewpoint of existing ideas on formation of H 5 O 2+ diaquohydrogen ions in the HPA structure. SoMe problems of stabilization of low-level hydrates of tungsten and molybdenum HPA are considered as well. The data of PMR low-temperature (80K) spectra have been used to identify the H 3 O + ions, H 2 O mole-- cules and small number of free protons in the investigated HPA. Taking this into account the H 5 O 2+ under the conditions of solid lattice is characterized as static distribution of proton between two molecules of the water of H 3 O + xH 2 O group. Dependence of the PMR spectra on temperature detects two transition regions, caused by mobility of the H 5 O 2+ elements. In the region of first transition (up to 250 K) the H 3 O + xH 2 O static configuration became dynamical, because of quick proton fluctuation along the 0...0 bond and librations of the H 2 O molequles. Then, higher than 250K, the H 5 O 2+ motion became more isotopic and then diffusion. Dynamical state of the H 5 O 2+ in H 3 PW 12 O 40 x6H 2 O and H 4 SiW 12 O 40 x6H 2 O hexahydrates in the wide temperature range is of limited nature, caused by specific of the H 5 O 2+ localizetion in the HPA structure

Recyclable Keggin Heteropolyacids as an Environmentally Benign Catalyst for the Synthesis of New 2-Benzoylamino-N-phenyl-benzamide Derivatives under Microwave Irradiations at Solvent-Free Conditions and the Evaluation of Biological Activity.

Science.gov (United States)

Ighilahriz-Boubchir, Karima; Boutemeur-Kheddis, Baya; Rabia, Cherifa; Makhloufi-Chebli, Malika; Hamdi, Maamar; Silva, Artur M S

2017-12-21

2-Benzoylamino- N -phenyl-benzamide derivatives ( 5a - h ) were prepared from 2-phenyl-3,1-(4 H )-benzoxazin-4-one 3 and substituted anilines 4a - h in the presence of a Keggin-type heteropolyacids series (H₃PW 12 O 40 ·13H₂O; H₄SiW 12 O 40 ·13H₂O; H₄SiMo 12 O 40 ·13H₂O; and H₃PMo 12 O 40 ·13H₂O) as catalysts without solvent and under microwave irradiation. We found that the use of H₃PW 12 O 40 ·13H₂O acid coupled to microwave irradiation allowed obtaining a high-yielding reaction with a short time. The compound structures were established by ¹H-NMR and 13 C-NMR. The antibacterial and antifungal activities of the synthesized compounds exhibited an inhibition of the growth of bacteria and fungi.

Isomerization-cracking of n-octane on catalysts based on heteropolyacid H{sub 3}Pw{sub 12}O{sub 40} and heteropolyacid supported on zirconia and promoted with Pt and Cs

Energy Technology Data Exchange (ETDEWEB)

Manuele, Debora L.; Torres, Gerardo C.; Benitez, Viviana M.; Badano, Juan M.; Yori, Juan C.; Sepulveda, Jorge H., E-mail: jsepulve@fiq.unl.edu.ar [Universidad Nacional de Litoral, Santa Fe (Argentina). Instituto de Investiaciones en Catalisis y Petroquimica. Consejo Nacional de Investigaciones Cientificas y Tecnicas

2013-10-01

Isomerization-cracking of n-octane was studied using H{sub 3}PW{sub 12}O{sub 40} (HPA) and HPA supported on zirconia and promoted with Pt and Cs. The addition of Pt and Cs to the supported HPA did not modify the Keggin structure. The Pt addition to the supported HPA did not substantially modify the total acidity; however, the Broensted acidity increased significantly. Cs increased the total acidity and Broensted acidity. A linear relation was observed between the n-C{sub 8} total conversion and Broensted acidity. The most adequate catalysts for performing isomerization and cracking to yield high research octane number (RON) are those with higher values of Broensted acidity. (author)

Preparation of (+)-α-terpineol from (+)-limonene: monoterpenes with pleasant odor in a project for undergraduate organic chemistry laboratory

International Nuclear Information System (INIS)

Baptistella, Lucia Helena Brito; Imamura, Paulo Mitsuo; Melo, Leandro Vilela de; Castello, Claudio

2009-01-01

A synthesis of (+)-α-terpineol from (+)-limonene was proposed as a project for undergraduate organic laboratory course. Terpineol is a useful flavor and fragrance compound, and several aspects of this preparation are suited for experimental organic classes, including basic techniques for extraction and analyses of essential oils, different reaction types and the possibility of a high degree of student interest. (author)

Role of D-Limonene in Autophagy Induced by Bergamot Essential Oil in SH-SY5Y Neuroblastoma Cells

Science.gov (United States)

Russo, Rossella; Cassiano, Maria Gilda Valentina; Ciociaro, Antonella; Adornetto, Annagrazia; Varano, Giuseppe Pasquale; Chiappini, Carlotta; Berliocchi, Laura; Tassorelli, Cristina; Bagetta, Giacinto; Corasaniti, Maria Tiziana

2014-01-01

Bergamot (Citrus bergamia, Risso et Poiteau) essential oil (BEO) is a well characterized, widely used plant extract. BEO exerts anxiolytic, analgesic and neuroprotective activities in rodents through mechanisms that are only partly known and need to be further investigated. To gain more insight into the biological effects of this essential oil, we tested the ability of BEO (0.005–0.03%) to modulate autophagic pathways in human SH-SY5Y neuroblastoma cells. BEO-treated cells show increased LC3II levels and appearance of dot-like formations of endogenous LC3 protein that colocalize with the lysosome marker LAMP-1. Autophagic flux assay using bafilomycin A1 and degradation of the specific autophagy substrate p62 confirmed that the observed increase of LC3II levels in BEO-exposed cells is due to autophagy induction rather than to a decreased autophagosomal turnover. Induction of autophagy is an early and not cell-line specific response to BEO. Beside basal autophagy, BEO also enhanced autophagy triggered by serum starvation and rapamycin indicating that the underlying mechanism is mTOR independent. Accordingly, BEO did not affect the phosphorylation of ULK1 (Ser757) and p70S6K (Thr389), two downstream targets of mTOR. Furthermore, induction of autophagy by BEO is beclin-1 independent, occurs in a concentration-dependent manner and is unrelated to the ability of BEO to induce cell death. In order to identify the active constituents responsible for these effects, the two most abundant monoterpenes found in the essential oil, d-limonene (125–750 µM) and linalyl acetate (62.5–375 µM), were individually tested at concentrations comparable to those found in 0.005–0.03% BEO. The same features of stimulated autophagy elicited by BEO were reproduced by d-limonene, which rapidly increases LC3II and reduces p62 levels in a concentration-dependent manner. Linalyl acetate was ineffective in replicating BEO effects; however, it greatly enhanced LC3 lipidation triggered by d-limonene

Recyclable Keggin Heteropolyacids as an Environmentally Benign Catalyst for the Synthesis of New 2-Benzoylamino-N-phenyl-benzamide Derivatives under Microwave Irradiations at Solvent-Free Conditions and the Evaluation of Biological Activity

Directory of Open Access Journals (Sweden)

Karima Ighilahriz-Boubchir

2017-12-01

Full Text Available 2-Benzoylamino-N-phenyl-benzamide derivatives (5a–h were prepared from 2-phenyl-3,1-(4H-benzoxazin-4-one 3 and substituted anilines 4a–h in the presence of a Keggin-type heteropolyacids series (H3PW12O40·13H2O; H4SiW12O40·13H2O; H4SiMo12O40·13H2O; and H3PMo12O40·13H2O as catalysts without solvent and under microwave irradiation. We found that the use of H3PW12O40·13H2O acid coupled to microwave irradiation allowed obtaining a high-yielding reaction with a short time. The compound structures were established by 1H-NMR and 13C-NMR. The antibacterial and antifungal activities of the synthesized compounds exhibited an inhibition of the growth of bacteria and fungi.

Journal of Chemical Sciences | Indian Academy of Sciences

Indian Academy of Sciences (India)

Nano-sized glass as an economically viable and eco-benign support to anchor heteropolyacids for green and sustainable chemoselective oxidation of sulfides to sulfoxides ... of the prepared catalyst were its recoverability and reusability for several reaction cycles, low-cost and toxicity, easy availability and facile production.

Chemical composition and acaricidal activity of the essential oil of Baccharis dracunculifolia De Candole (1836) and its constituents nerolidol and limonene on larvae and engorged females of Rhipicephalus microplus (Acari: Ixodidae).

Science.gov (United States)

de Assis Lage, Tiago Coelho; Montanari, Ricardo Marques; Fernandes, Sergio Antonio; de Oliveira Monteiro, Caio Márcio; de Oliveira Souza Senra, Tatiane; Zeringota, Viviane; da Silva Matos, Renata; Daemon, Erik

2015-01-01

Baccharis dracunculifolia DC (common name "alecrim-do-campo" in Brazil) is a plant with widespread distribution in South America that is the botanical origin of green propolis. The aim of this study was to evaluate the chemical composition and acaricidal activity of the essential oil of B. dracunculifolia and its constituents nerolidol and limonene on unengorged larvae and engorged females of Rhipicephalus microplus (Acari: Ixodidae). The essential oil yield was 0.8% of dry mass and the major constituents were nerolidol (22.3%), germacrene D (7.2%), limonene (6.9%), β-pinene (6.7) and bicyclogermacrene (6.5%). The acaricidal activity of the essential oil and the pure compounds nerolidol and (R)-(+)-limonene were assessed in the laboratory through the modified larval packet test (LPT) and the female immersion test (FIT). In the LPT, the essential oil and nerolidol were both active, causing more than 90% mortality at concentrations from 15.0 and 10.0 mg mL(-1), respectively, whereas (R)-(+)-limonene was not active. In the FIT, the oil and nerolidol caused reduction in the quantity and quality of eggs produced, with control percentages of 96.3% and 90.3% at concentrations of 60.0 and 50.0 mg mL(-1), respectively. It can be concluded that the essential oil obtained from the aerial parts of B. dracunculifolia and its major component nerolidol have high activity on R. microplus larvae and engorged females. Copyright © 2014 Elsevier Inc. All rights reserved.

Evaluation of the antimicrobial efficacy of Minthostachys verticillata essential oil and limonene against Streptococcus uberis strains isolated from bovine mastitis.

Science.gov (United States)

Montironi, Ivana D; Cariddi, Laura N; Reinoso, Elina B

Bovine mastitis is a disease that causes great economic losses per year, being Streptococcus uberis the main environmental pathogen involved. The aim of the present study was to determine the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of Minthostachys verticillata essential oil and limonene for S. uberis strains isolated from bovine mastitis. In addition, the effect of MIC on biofilm formation was analyzed. MIC values for the essential oil ranged from 14.3 to 114.5mg/ml (1.56-12.5%v/v) and MBC between 114.5 and 229mg/ml (12.5-25%v/v). MICs for limonene ranged from 3.3 to 52.5mg/ml (0.39-6.25%v/v) and MBC was 210mg/ml (25%v/v). Both compounds showed antibacterial activity and affected the biofilm formation of most of the strains tested. In conclusion, these compounds could be used as an alternative and/or complementary therapy for bovine mastitis caused by S. uberis. Copyright © 2016 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

Effect of trans-anethole, limonene and your combination in nutritional components and their reflection on reproductive parameters and testicular apoptosis in Spodoptera frugiperda (Lepidoptera: Noctuidae).

Science.gov (United States)

Cruz, Glaucilane S; Wanderley-Teixeira, Valéria; Oliveira, José V; D' Assunção, Carolline G; Cunha, Franklin M; Teixeira, Álvaro A C; Guedes, Carolina A; Dutra, Kamilla A; Barbosa, Douglas R S; Breda, Mariana O

2017-02-01

Spodoptera frugiperda is a major pest in several crops due to its polyphagous habit. Studies on the use of essential oils for pest control have been increasing over the years, presenting itself as a promising alternative with less environmental impact. Chemical profile evaluations of essential oils enable the knowledge and use of major compounds, providing a better understanding of their actions in the life history of insects. Thus, the study evaluated the effects of the major compounds limonene, trans-anethole and the combined effects upon nutrition, reproduction and testicular apoptosis in S. frugiperda. Larvae of third instar were submitted to the LD 50 of the compounds by topical contact and 48 h later the amounts of lipids, proteins, total sugar and glycogen were evaluated. The testicular apoptosis was evaluated in the treated larvae after 48 h and the reproductive parameters were evaluated after adult emergence. All treatments reduced the amounts of lipid, protein, total sugar and glycogen when compared to control. The most significant results were obtained by the association of compounds. All treatments reduced the number of eggs, oviposition period and adult longevity when compared to control. There were no changes in the pre-oviposition and post-oviposition periods. Testicular apoptosis was observed in the limonene and in the combined treatments. It is concluded that limonene and trans-anethole, especially in association, cause adverse effects upon nutrition and reproduction in S. frugiperda, altering essential parameters for its survival and establishment on crops. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Photocatalytic Degradation of Toluene, Butyl Acetate and Limonene under UV and Visible Light with Titanium Dioxide-Graphene Oxide as Photocatalyst

Directory of Open Access Journals (Sweden)

Birte Mull

2017-01-01

Full Text Available Photocatalysis is a promising technique to reduce volatile organic compounds indoors. Titanium dioxide (TiO2 is a frequently-used UV active photocatalyst. Because of the lack of UV light indoors, TiO2 has to be modified to get its working range shifted into the visible light spectrum. In this study, the photocatalytic degradation of toluene, butyl acetate and limonene was investigated under UV LED light and blue LED light in emission test chambers with catalysts either made of pure TiO2 or TiO2 modified with graphene oxide (GO. TiO2 coated with different GO amounts (0.75%–14% were investigated to find an optimum ratio for the photocatalytic degradation of VOC in real indoor air concentrations. Most experiments were performed at a relative humidity of 0% in 20 L emission test chambers. Experiments at 40% relative humidity were done in a 1 m³ emission test chamber to determine potential byproducts. Degradation under UV LED light could be achieved for all three compounds with almost all tested catalyst samples up to more than 95%. Limonene had the highest degradation of the three selected volatile organic compounds under blue LED light with all investigated catalyst samples.

ANALYSIS OF SECONDARY ORGANIC AEROSOL COMPOUNDS FROM THE PHOTOOXIDATION OF D-LIMONENE IN THE PRESENCE OF NO X AND THEIR DETECTION IN AMBIENT PM 2.5

Science.gov (United States)

Chemical analysis of secondary organic aerosol (SOA) from the photooxidation of a d-limonene/NOx/air mixture was carried out. SOA, generated in a smog chamber, was collected on Zefluor filters. To determine the structural characteristics of the compounds, the filter sample...

Stereochemical analysis of (+)-limonene using theoretical and experimental NMR and chiroptical data

Science.gov (United States)

Reinscheid, F.; Reinscheid, U. M.

2016-02-01

Using limonene as test molecule, the success and the limitations of three chiroptical methods (optical rotatory dispersion (ORD), electronic and vibrational circular dichroism, ECD and VCD) could be demonstrated. At quite low levels of theory (mpw1pw91/cc-pvdz, IEFPCM (integral equation formalism polarizable continuum model)) the experimental ORD values differ by less than 10 units from the calculated values. The modelling in the condensed phase still represents a challenge so that experimental NMR data were used to test for aggregation and solvent-solute interactions. After establishing a reasonable structural model, only the ECD spectra prediction showed a decisive dependence on the basis set: only augmented (in the case of Dunning's basis sets) or diffuse (in the case of Pople's basis sets) basis sets predicted the position and shape of the ECD bands correctly. Based on these result we propose a procedure to assign the absolute configuration (AC) of an unknown compound using the comparison between experimental and calculated chiroptical data.

Measurement and correlation of (vapor + liquid) equilibrium data for {α-pinene + p-cymene + (S)-(−)-limonene} ternary system at atmospheric pressure

International Nuclear Information System (INIS)

Sun, Lixia; Liao, Dankui; Yang, Zhengyu; Chen, Xiaopeng; Tong, Zhangfa

2013-01-01

Highlights: ► The VLE data of (α-pinene + p-cymene) and (α-pinene + p-cymene + (S)-(−)-limonene) at atmospheric pressure were measured. ► The VLE data of binary system were correlated by four activity coefficient models. ► The ternary VLE data were predicted from binary parameters of the Liebermann–Fried model. ► The constant G 123 E counters plotted on the Roozeboom diagrams. -- Abstract: (Vapor + liquid) equilibrium (VLE) data for binary system of (α-pinene + p-cymene) and ternary system of {α-pinene + p-cymene + (S)-(−)-limonene} were measured at 100.7 kPa using the modified Ellis equilibrium still. The VLE data are thermodynamically consistent. Parameters of the binary system for the four solution models — Liebermann–Fried, Wilson, NRTL, and UNIQUAC — were calculated by referencing least squares method to minimize an objective function based on the total pressure. The ternary system data were predicted with the parameters of Liebermann–Fried model obtained from the pertinent binary systems. The predicted bubble-point temperature and the vapor composition for the ternary system were in good agreement with the experimental results. Smooth representations of the results are used to construct constant excess Gibbs free energy contours on Roozeboom diagrams

DETAILED ANALYSIS OF SOA ORIGINATING FROM THE PHOTOOXIDATION OF D-LIMONENE IN THE PRESENCE OF NO X AND UV LIGHT AND ITS IMPLICATION TO AMBIENT PM 2.5

Science.gov (United States)

A detailed analysis was carried out of the aerosol phase originated from the photooxidation of d-limonene in the presence of NOx and artificial light with the analytical emphasis on the identification of oxygenated organic compounds. The major components included six ...

A High-Performance Recycling Solution for Polystyrene Achieved by the Synthesis of Renewable Poly(thioether) Networks Derived from d-Limonene

Science.gov (United States)

Nash, Landon D.; Rodriguez, Jennifer N.; Lonnecker, Alexander T.; Raymond, Jeffery E.; Wilson, Thomas S.; Wooley, Karen L.; Maitland, Duncan J.

2014-01-01

Nanocomposite polymers have been prepared using a new sustainable materials synthesis process in which d-Limonene functions simultaneously both as a solvent for recycling polystyrene (PS) waste and as a monomer that undergoes UV-catalyzed thiol-ene polymerization reactions with polythiol co-monomers to afford polymeric products comprised of precipitated PS phases dispersed throughout elastomeric poly(thioether) networks. These blended networks exhibit mechanical properties that greatly exceed those of either polystyrene or the poly(thioether) network homopolymers alone. PMID:24249666

Aggregation of Heteropolyanions Implicates the Presence of Zundel Ions Near Air-Water Interfaces

Energy Technology Data Exchange (ETDEWEB)

Bera, Mrinal K. [Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne Illinois 60439 United States; DUBBLE-CRG, ESRF-The European Synchrotron Radiation Facility CS40220, 38043 Grenoble Cedex 9 France; Antonio, Mark R. [Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne Illinois 60439 United States

2016-07-01

Protons play crucial roles in the interactions between hetero-polyanions (HPAs) in aqueous solutions and solid acid salts. We report the aggregation behaviours of Keggin HPAs near the surfaces of heteropolyacid solutions. The structure of the aggregated HPA layer near the solution-vapour phase boundary closely resembles the solid-state crystal structure of the hetero-polyacids in which the HPAs are connected by Zundel ions. The resemblance not only implicates the presence of protons in the form of planar Zundel ions near the air-water interface but, also, suggests that these align parallel to the interface. This study demonstrates an indirect means of assessing the impact of protons on HPA interactions near air-water interfaces and, in general, provides new insights about interfacial proton chemistry of heteropolyacids.

Activation of charcoal made from japanese cypress as oxygen electrode in fuel cell by deposition of Pd-metal/Heteropolyacids of the micropores; Kinzokuparajiumu-heteroporisan no bunsan tanzi niyoru hinoki mokutan no nenryo denchisansokyoku to shiteno kinouka

Energy Technology Data Exchange (ETDEWEB)

Yumine, Takuya.; Kominami, Hiroshi.; Kera, Yoshiya. [Kinki University, osaka (Japan); Abe, Ikuo. [Osaka Municipal Technology Research Institute, Osaka (Japan)

1998-12-31

Pd- and Pt-metal were observed by TEM to be highly disperdsed on charcoal prepared from Japanese Cypress [Hinoki] at 900degreeC (Pd, Pt/H2). Nafion-sheet was hot-pressed with Pd/H2 and Pt/H2 disc-pellets placed in the other sides to make a fuel cell-electrode unit. The 1-V curve in the H{sub 2}-O{sub 2} fuel were measured : The voltage certainly grew with increase in the amount of Pd-metal (1{yields}13wt%) and with a mixing of [Nafion] powder (11wt%). The discharge character was greatly improved with the addition of heteropolyacid (H{sub 3}PMo{sub 11}VO{sub 42};PVMo{sub 11}). When a charcoal prepared from Hinoki at 2400degreeC (HG) was used, the inner resistivity was about 10-times lower than the case of H2 used, although the dispersed states of Pd-metal became considerably poor on HG rather than H2. The actuvuty also increased further with the addition of Nafion and PVMo{sub 11}. (author)

Vanadium-substituted heteropolyacids immobilized on amine- functionalized mesoporous MCM-41: A recyclable catalyst for selective oxidation of alcohols with H2O2

International Nuclear Information System (INIS)

Dong, Xinbo; Wang, Danjun; Li, Kebin; Zhen, Yanzhong; Hu, Huaiming; Xue, Ganglin

2014-01-01

Graphical abstract: Vanadium-substituted phosphotungstic acids are immobilized on amine- functionalized mesoporous MCM-41 and the hybrid catalyst is proved to be a highly efficient solid catalyst for the oxidation of aromatic alcohols to the corresponding carbonyl compounds with H 2 O 2 , featured by the high conversion and selectivity, easy recovery, and quite steady reuse. - Highlights: • Vanadium-substituted phosphotungstic acid immobilized on amine-functionalized mesoporous MCM-41 are prepared. • HPAs were fixed on the inner surface of mesoporous MCM-41 by chemical bonding to aminosilane groups. • The hybrid catalyst showed much higher catalytic activity than the pure HPAs. • The hybrid catalyst is a highly efficient recyclable solid catalyst for the selective oxidation of aromatic alcohols. - Abstract: New hybrid materials of vanadium-substituted phosphotungstic acids (VHPW) immobilized on amine-functionalized mesoporous MCM-41 (VHPW/MCM-41/NH 2 ) are prepared and characterized by FT-IR, XRD, N 2 adsorption, elemental analysis, SEM and TEM for their structural integrity and physicochemical properties. It is found that the structure of the heteropolyacids is retained upon immobilization over mesoporous materials. The catalytic activities of these hybrid materials are tested in the selective oxidation of alcohols to the carbonyl products with 30% aqueous H 2 O 2 as oxidant in toluene. The catalytic activities of different number of vanadium-substituted phosphotungstic acid are investigated, and among the catalysts, H 5 [PV 2 W 10 O 40 ] immobilized on amine-functionalized MCM-41 exhibits the highest activity with 97% conversion and 99% selectivity in the oxidation of benzyl alcohol to benzaldehyde. The hybrid catalyst is proved to be a highly efficient recyclable solid catalyst for the selective oxidation of aromatic alcohols to the corresponding aldehydes with H 2 O 2

Radiation-induced cationic polymerization of limonene oxide, α-pinene oxide, and β-pinene oxide

International Nuclear Information System (INIS)

Aikins, J.A.; Williams, F.

1985-01-01

After suitable drying, the subject monomers in the form of neat liquids undergo radiation-induced polymerization with no apparent side reactions and high conversions to precipitatable polymers of low molecular weights. A high frequency of chain (proton) transfer to monomer is indicated by the fact that the kinetic chain lengths are estimated to be several hundred times larger than the range of DP/sub n/ values (12-4). Structural characterization of the limonene oxide polymer by 1 H and 13 C NMR spectroscopy provides conclusive evidence that the polymerization proceeds by the opening of the epoxide ring to yield a 1,2-trans polyether. Similar NMR studies on the polymers formed from the α-pinene and β-pinene oxides show that the opening of the epoxide ring for these monomers is generally accompanied by the concomitant ring opening of the cyclobutane ring structure to yield a gem-di-methyl group in the main chain

Application of extraction of gallium molybdotungstate HPA for their investigation in solutions and gallium determination

International Nuclear Information System (INIS)

Kol'tsova, E.G.; Vakulich, A.N.; Tsyganok, L.P.

2001-01-01

Extraction of gallium molybdotungstate heteropolyacids and their associates with a row of triphenylmethane dyes, use of extraction for study of complexing in Mo 6 -W 6 -Ga 3+ -H 3 O + system are investigated. Research of optimal analytical states and development of extraction spectrophotometric methods of gallium determination are done. It is shown that increase of Mo 6 part in heteropolyanion improves solvation interaction of heteropolyacids with organic solvents elevating extraction properties of polyanion [ru

Indoor transient SOA formation from ozone + α-pinene reactions: Impacts of air exchange and initial product concentrations, and comparison to limonene ozonolysis

Science.gov (United States)

Youssefi, Somayeh; Waring, Michael S.

2015-07-01

The ozonolysis of reactive organic gases (ROG), e.g. terpenes, generates secondary organic aerosol (SOA) indoors. The SOA formation strength of such reactions is parameterized by the aerosol mass fraction (AMF), a.k.a. SOA yield, which is the mass ratio of generated SOA to oxidized ROG. AMFs vary in magnitude both among and for individual ROGs. Here, we quantified dynamic SOA formation from the ozonolysis of α-pinene with 'transient AMFs,' which describe SOA formation due to pulse emission of a ROG in an indoor space with air exchange, as is common when consumer products are intermittently used in ventilated buildings. We performed 19 experiments at low, moderate, and high (0.30, 0.52, and 0.94 h-1, respectively) air exchange rates (AER) at varying concentrations of initial reactants. Transient AMFs as a function of peak SOA concentrations ranged from 0.071 to 0.25, and they tended to increase as the AER and product of the initial reactant concentrations increased. Compared to our similar research on limonene ozonolysis (Youssefi and Waring, 2014), for which formation strength was driven by secondary ozone reactions, the AER impact for α-pinene was opposite in direction and weaker, while the initial reactant product impact was in the same direction but stronger for α-pinene than for limonene. Linear fits of AMFs for α-pinene ozonolysis as a function of the AER and initial reactant concentrations are provided so that future indoor models can predict SOA formation strength.

Principal component analysis (PCA of volatile terpene compounds dataset emitted by genetically modified sweet orange fruits and juices in which a D-limonene synthase was either up- or down-regulated vs. empty vector controls

Directory of Open Access Journals (Sweden)

Ana Rodríguez

2016-12-01

Full Text Available We have categorized the dataset from content and emission of terpene volatiles of peel and juice in both Navelina and Pineapple sweet orange cultivars in which D-limonene was either up- (S, down-regulated (AS or non-altered (EV; control (“Impact of D-limonene synthase up- or down-regulation on sweet orange fruit and juice odor perception”(A. Rodríguez, J.E. Peris, A. Redondo, T. Shimada, E. Costell, I. Carbonell, C. Rojas, L. Peña, (2016 [1]. Data from volatile identification and quantification by HS-SPME and GC–MS were classified by Principal Component Analysis (PCA individually or as chemical groups. AS juice was characterized by the higher influence of the oxygen fraction, and S juice by the major influence of ethyl esters. S juices emitted less linalool compared to AS and EV juices.

P, ρ, and T measurements of the (limonene + β-pinene) mixtures

International Nuclear Information System (INIS)

Langa, Elisa; Palavra, Antonio M.F.; Nieto de Castro, Carlos A.; Mainar, Ana M.

2012-01-01

Highlights: ► Density as a function of P, T and composition was measured for pinene mixtures. ► Isothermal compressibility and coefficients of cubic expansion were also calculated. ► Usual behaviour of these three properties was found. ► SAFT and PC-SAFT were used as predictive models, showing PC-SAFT the best predictions. - Abstract: The density, ρ, and two derived properties, isothermal compressibility, κ T , and the coefficient of cubic expansion, α P , were obtained for the mixtures of 1-methyl-4-(1-methylethenyl)-cyclohexene, known as limonene, and (1S,5S)-6,6-dimethyl-2-methylenebibyclo[3.1.1]heptane, known as β-pinene, for nine different compositions and the pure components at five pressures from 20 MPa to 40 MPa and six temperatures from 283.15 K to 358.15 K. The experimental uncertainty for ρ, κ T , and α P were respectively ±0.5 kg · m −3 , ±14 TPa −1 , and ±0.005k K −1 , with k = 2 for all of them. Density behaviour with temperature and pressure was as expected. The values of α P and κ T increase with temperature and decrease with increasing pressure. Two different equations of state, conventional SAFT and PC-SAFT, were applied to predict the densities of the mixture. The best predictions were achieved with PC-SAFT.

Inflammatory effects induced by selected limonene oxidation products: 4-OPA, IPOH, 4-AMCH in human bronchial (16HBE14o-) and alveolar (A549) epithelial cell lines.

Science.gov (United States)

Lipsa, Dorelia; Leva, Paolo; Barrero-Moreno, Josefa; Coelhan, Mehmet

2016-11-16

Limonene, a monoterpene abundantly present in most of the consumer products (due to its pleasant citrus smell), easily undergoes ozonolysis leading to several limonene oxidation products (LOPs) such as 4-acetyl-1-methylcyclohexene (4-AMCH), 4-oxopentanal (4-OPA) and 3-isopropenyl-6-oxoheptanal (IPOH). Toxicological studies have indicated that human exposure to limonene and ozone can cause adverse airway effects. However, little attention has been paid to the potential health impact of specific LOPs, in particular of IPOH, 4-OPA and 4-AMCH. This study evaluates the cytotoxic effects of the selected LOPs on human bronchial epithelial (16HBE14o-) and alveolar epithelial (A549) cell lines by generating concentration-response curves using the neutral red uptake assay and analyzing the inflammatory response with a series of cytokines/chemokines. The cellular viability was mostly reduced by 4-OPA [IC 50 =1.6mM (A549) and 1.45mM (16HBE14o-)] when compared to IPOH [IC 50 =3.5mM (A549) and 3.4mM (16HBE14o-)] and 4-AMCH [IC 50 could not be calculated]. As a result from the inflammatory response, IPOH [50μM] induced an increase of both IL-6 and IL-8 secretion in A549 (1.5-fold change) and in 16HBE14o- (2.8- and 7-fold change respectively). 4-OPA [50μM] treatment of A549 increased IL-6 (1.4-times) and IL-8 (1.3-times) levels, while in 16HBE14o- had an opposite effect. A549 treated with 4-AMCH [50μM] elevate both IL-6 and IL-8 levels by 1.2-times, while in 16HBE14o- had an opposite effect. Based on our results, lung cellular injury characterized by inflammatory cytokine release was observed for both cell lines treated with the selected chemicals at concentrations that did not affect their cellular viability. Copyright © 2016 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

Vanadium-substituted heteropolyacids immobilized on amine- functionalized mesoporous MCM-41: A recyclable catalyst for selective oxidation of alcohols with H{sub 2}O{sub 2}

Energy Technology Data Exchange (ETDEWEB)

Dong, Xinbo [Key Laboratory of Synthetic and Natural Functional Molecule Chemistry, Department of Chemistry (Ministry of Education), Northwest University, Xi' an 710069 (China); Wang, Danjun [Key Laboratory of Synthetic and Natural Functional Molecule Chemistry, Department of Chemistry (Ministry of Education), Northwest University, Xi' an 710069 (China); College of Chemistry Chemical Engineering, Yanan University, Shaanxi Key Laboratory of Chemical Reaction Engineering, Yan' an 716000 (China); Li, Kebin [Key Laboratory of Synthetic and Natural Functional Molecule Chemistry, Department of Chemistry (Ministry of Education), Northwest University, Xi' an 710069 (China); Zhen, Yanzhong [Key Laboratory of Synthetic and Natural Functional Molecule Chemistry, Department of Chemistry (Ministry of Education), Northwest University, Xi' an 710069 (China); College of Chemistry Chemical Engineering, Yanan University, Shaanxi Key Laboratory of Chemical Reaction Engineering, Yan' an 716000 (China); Hu, Huaiming [Key Laboratory of Synthetic and Natural Functional Molecule Chemistry, Department of Chemistry (Ministry of Education), Northwest University, Xi' an 710069 (China); Xue, Ganglin, E-mail: xglin707@163.com [Key Laboratory of Synthetic and Natural Functional Molecule Chemistry, Department of Chemistry (Ministry of Education), Northwest University, Xi' an 710069 (China)

2014-09-15

Graphical abstract: Vanadium-substituted phosphotungstic acids are immobilized on amine- functionalized mesoporous MCM-41 and the hybrid catalyst is proved to be a highly efficient solid catalyst for the oxidation of aromatic alcohols to the corresponding carbonyl compounds with H{sub 2}O{sub 2}, featured by the high conversion and selectivity, easy recovery, and quite steady reuse. - Highlights: • Vanadium-substituted phosphotungstic acid immobilized on amine-functionalized mesoporous MCM-41 are prepared. • HPAs were fixed on the inner surface of mesoporous MCM-41 by chemical bonding to aminosilane groups. • The hybrid catalyst showed much higher catalytic activity than the pure HPAs. • The hybrid catalyst is a highly efficient recyclable solid catalyst for the selective oxidation of aromatic alcohols. - Abstract: New hybrid materials of vanadium-substituted phosphotungstic acids (VHPW) immobilized on amine-functionalized mesoporous MCM-41 (VHPW/MCM-41/NH{sub 2}) are prepared and characterized by FT-IR, XRD, N{sub 2} adsorption, elemental analysis, SEM and TEM for their structural integrity and physicochemical properties. It is found that the structure of the heteropolyacids is retained upon immobilization over mesoporous materials. The catalytic activities of these hybrid materials are tested in the selective oxidation of alcohols to the carbonyl products with 30% aqueous H{sub 2}O{sub 2} as oxidant in toluene. The catalytic activities of different number of vanadium-substituted phosphotungstic acid are investigated, and among the catalysts, H{sub 5}[PV{sub 2}W{sub 10}O{sub 40}] immobilized on amine-functionalized MCM-41 exhibits the highest activity with 97% conversion and 99% selectivity in the oxidation of benzyl alcohol to benzaldehyde. The hybrid catalyst is proved to be a highly efficient recyclable solid catalyst for the selective oxidation of aromatic alcohols to the corresponding aldehydes with H{sub 2}O{sub 2}.

MODELING AND SIMULATION OF A BATCH DISTILLATION COLUMN FOR RECOVERING LIMONENE EPOXIDE MODELAGEM E SIMULAÇÃO DE UMA COLUNA DE DESTILAÇÃO POR LOTES PARA RECUPERAR EPÓXIDO DE LIMONENO

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Rolando Barrera Zapata

2012-12-01

Full Text Available Aspen Plus and MATLAB software simulation tools were employed for modeling, simulation and optimization of a distillation process to recover limonene epoxide from a liquid mixture containing limonene + acetonitrile + water + limonene epoxide. This mixture is obtained from limonene epoxidation over PW-Amberlite using aqueous hydrogen peroxide as oxidant and acetonitrile as solvent. Analyses of residue curve maps indicate that batch distillation columns of inverse configuration are adequate to separate limonene epoxide. The model parameters, i.e., the number of stages (8 and the reflux ratio (3,1 were determined by steady state simulations with short-cut models and rigorous models from Aspen Plus. Aspen Plus simulation of the batch distillation operation showed that it is possible to recover up to 95 % limonene epoxide with a molar fraction of 0,97 after 7,5 h. For comparison purposes, the batch distillation operation was also simulated with a semi-rigorous MATLAB model and similar results were obtained.Se emplearon herramientas de software de simulación como Aspen Plus y MATLAB para el modelado, simulación y optimización de un proceso de destilación para recuperar epóxido de limoneno a partir de una mezcla líquida que contiene limoneno + acetonitrilo + agua + epóxido de limoneno. Esta mezcla se obtiene de la epoxidación de limoneno sobre PW-Amberlita utilizando peróxido de hidrógeno acuoso como oxidante y acetonitrilo como disolvente. Los análisis de curvas de composición residual indicaron que las columnas de destilación por lotes de configuración inversa son adecuadas para separar el epóxido de limoneno. Los parámetros del modelo, como el número de etapas (8 y la relación de reflujo (3,1 se determinaron mediante simulaciones de estado estacionario con modelos cortos y rigurosos de Aspen Plus. La simulación del equipo por lotes en Aspen Plus mostró que es posible recuperar hasta el 95 % del epóxido de limoneno con una fracci

Study on solar chemical heat pump system. Basic experiment on dehydrogenation of 2-propanol using heteropoly-acid photo catalyst; Solar chemical heat pump no kenkyu. Heteropoly sankei hikari shokubai wo mochiita 2-propanol no dassuiso hanno

Energy Technology Data Exchange (ETDEWEB)

Doi, T [Electrochemical Laboratory, Tsukuba (Japan); T-Raissi, A; Muradov, N [Florida Solar Energy Center, FL (United States)

1996-10-27

With the purpose of converting solar heat energy to an industrial heat energy, an examination was carried out empirically on the case of using a heteropoly-acid photo catalyst for the decomposition reaction process of 2-propanol. The experiment was performed in Florida Solar Energy Center, in the U.S.A.. The device for the experiment was constituted of a reaction part, distribution manifold for feeding from the lower part of the reaction part a 2-propanol solution for which a photo catalyst was suspended, storage tank served also as a gas-liquid separating container, and circulating pump. Silica-tangstic acid was used as the photo catalyst. In an outdoor experiment using solar radiation, the quantity of inclined global solar radiation was 530-950W/m{sup 2} in clear days and 100-600W/m{sup 2} in cloudy days, with temperatures between 17 and 26{degree}C throughout the experiment period. In addition, an indoor experiment was also conducted using an artificial light source (UV light). As a result of the experiment, the energy conversion efficiency was at most about 1% of incident UV light, a low figure compared to a heat utilization ratio of approximately 15% with a thermal catalyst. 6 refs., 8 figs.

Benzaldehyde thiosemicarbazone derived from limonene complexed with copper induced mitochondrial dysfunction in Leishmania amazonensis.

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Elizandra Aparecida Britta

Full Text Available BACKGROUND: Leishmaniasis is a major health problem that affects more than 12 million people. Treatment presents several problems, including high toxicity and many adverse effects, leading to the discontinuation of treatment and emergence of resistant strains. METHODOLOGY/PRINCIPAL FINDINGS: We evaluated the in vitro antileishmanial activity of benzaldehyde thiosemicarbazone derived from limonene complexed with copper, termed BenzCo, against Leishmania amazonensis. BenzCo inhibited the growth of the promastigote and axenic amastigote forms, with IC(50 concentrations of 3.8 and 9.5 µM, respectively, with 72 h of incubation. Intracellular amastigotes were inhibited by the compound, with an IC(50 of 10.7 µM. BenzCo altered the shape, size, and ultrastructure of the parasites. Mitochondrial membrane depolarization was observed in protozoa treated with BenzCo but caused no alterations in the plasma membrane. Additionally, BenzCo induced lipoperoxidation and the production of mitochondrial superoxide anion radicals in promastigotes and axenic amastigotes of Leishmania amazonensis. CONCLUSION/SIGNIFICANCE: Our studies indicated that the antileishmania activity of BenzCo might be associated with mitochondrial dysfunction and oxidative damage, leading to parasite death.

Wavelength dependent photoelectron circular dichroism of limonene studied by femtosecond multiphoton laser ionization and electron-ion coincidence imaging

Science.gov (United States)

Rafiee Fanood, Mohammad M.; Janssen, Maurice H. M.; Powis, Ivan

2016-09-01

Enantiomers of the monoterpene limonene have been investigated by (2 + 1) resonance enhanced multiphoton ionization and photoelectron circular dichroism employing tuneable, circularly polarized femtosecond laser pulses. Electron imaging detection provides 3D momentum measurement while electron-ion coincidence detection can be used to mass-tag individual electrons. Additional filtering, by accepting only parent ion tagged electrons, can be then used to provide discrimination against higher energy dissociative ionization mechanisms where more than three photons are absorbed to better delineate the two photon resonant, one photon ionization pathway. The promotion of different vibrational levels and, tentatively, different electronic ion core configurations in the intermediate Rydberg states can be achieved with different laser excitation wavelengths (420 nm, 412 nm, and 392 nm), in turn producing different state distributions in the resulting cations. Strong chiral asymmetries in the lab frame photoelectron angular distributions are quantified, and a comparison made with a single photon (synchrotron radiation) measurement at an equivalent photon energy.

(Liquid + liquid) equilibria of (water + linalool + limonene) ternary system at T = (298.15, 308.15, and 318.15) K

International Nuclear Information System (INIS)

Gramajo de Doz, Monica B.; Cases, Alicia M.; Solimo, Horacio N.

2008-01-01

(Liquid + liquid) equilibrium (LLE) data for {water (1) + linalool (2) + limonene (3)} ternary system at T = (298.15, 308.15, and 318.15 ± 0.05) K are reported. The organic chemicals were quantified by gas chromatography using a flame ionisation detector while water was quantified using a thermal conductivity detector. The effect of the temperature on (liquid + liquid) equilibrium is determined and discussed. Experimental data for the ternary mixture are compared with values calculated by the NRTL and UNIQUAC equations, and predicted by means of the UNIFAC group contribution method. It is found that the UNIQUAC and NRTL models provide a good correlation of the solubility curve at these three temperatures, while comparing the calculated values with the experimental ones, the best fit is obtained with the NRTL model. Finally, the UNIFAC model provides poor results, since it predicts a greater heterogeneous region than experimentally observed

Direct Activation Of Methane

KAUST Repository

Basset, Jean-Marie

2013-07-15

Heteropolyacids (HPAs) can activate methane at ambient temperature (e.g., 20.degree. C.) and atmospheric pressure, and transform methane to acetic acid, in the absence of any noble metal such as Pd). The HPAs can be, for example, those with Keggin structure: H.sub.4SiW.sub.12O.sub.40, H.sub.3PW.sub.12O.sub.40, H.sub.4SiMo.sub.12O.sub.40, or H.sub.3PMo.sub.12O.sub.40, can be when supported on silica.

Preparation of (+)-{alpha}-terpineol from (+)-limonene: monoterpenes with pleasant odor in a project for undergraduate organic chemistry laboratory; Preparacao do (+)-{alpha}-terpineola a partir do (+)-limoneno: monoterpenos de odor agradavel em um projeto para quimica organica experimental

Energy Technology Data Exchange (ETDEWEB)

Baptistella, Lucia Helena Brito; Imamura, Paulo Mitsuo; Melo, Leandro Vilela de; Castello, Claudio [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Inst. de Quimica], e-mail: lhbb@iqm.unicamp.br

2009-07-01

A synthesis of (+)-{alpha}-terpineol from (+)-limonene was proposed as a project for undergraduate organic laboratory course. Terpineol is a useful flavor and fragrance compound, and several aspects of this preparation are suited for experimental organic classes, including basic techniques for extraction and analyses of essential oils, different reaction types and the possibility of a high degree of student interest. (author)

Intense Vibronic Modulation of the Chiral Photoelectron Angular Distribution Generated by Photoionization of Limonene Enantiomers with Circularly Polarized Synchrotron Radiation.

Science.gov (United States)

Rafiee Fanood, Mohammad M; Ganjitabar, Hassan; Garcia, Gustavo A; Nahon, Laurent; Turchini, Stefano; Powis, Ivan

2018-04-17

Photoionization of the chiral monoterpene limonene has been investigated using polarized synchrotron radiation between the adiabatic ionization threshold, 8.505 and 23.5 eV. A rich vibrational structure is seen in the threshold photoelectron spectrum and is interpreted using a variety of computational methods. The corresponding photoelectron circular dichroism-measured in the photoelectron angular distribution as a forward-backward asymmetry with respect to the photon direction-was found to be strongly dependent on the vibronic structure appearing in the photoelectron spectra, with the observed asymmetry even switching direction in between the major vibrational peaks. This effect can be ultimately attributed to the sensitivity of this dichroism to small phase shifts between adjacent partial waves of the outgoing photoelectron. These observations have implications for potential applications of this chiroptical technique, where the enantioselective analysis of monoterpene components is of particular interest. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

X-ray absorption spectroscopy of the chiral molecules fenchone, α-pinene, limonene and carvone in the C1s excitation region

Energy Technology Data Exchange (ETDEWEB)

Ozga, Christian, E-mail: ozga@physik.uni-kassel.de [Institute for Physics and CINSaT, University of Kassel, Heinrich-Plett Str. 40, 34132 Kassel (Germany); Jänkälä, Kari [Centre for Molecular Materials Research, University of Oulu, PO Box 3000, 90014 Oulu (Finland); Schmidt, Philipp; Hans, Andreas; Reiß, Philipp; Ehresmann, Arno; Knie, André [Institute for Physics and CINSaT, University of Kassel, Heinrich-Plett Str. 40, 34132 Kassel (Germany)

2016-02-15

Highlights: • Determination of the X-ray absorption spectra for two terpenoids and two terpenes. • Allocation of predominant or even site-selective excitation of stereocenters. • Fragment fluorescence spectra of the prototype molecules are identical. • Presented data can be used for future fluorescence circular dichroism experiments. - Abstract: Relative ionization cross sections and fluorescence intensities as functions of the exciting-photon energy were recorded for the chiral molecules carvone, α-pinene, limonene and fenchone after excitation by monochromatized synchrotron radiation with energies of the exciting-photons between 284 eV and 289 eV. At selected exciting-photon energies dispersed fragment fluorescence spectra in the wavelength range between 365 nm and 505 nm were obtained. Time dependent density functional theory (TD-DFT) computations were performed to analyze the experimentally observed resonance-structures. Comparison of the computed and recorded spectra demonstrates the possibility of a predominant or even specific excitation of one particular stereocenter site in a molecule with more than one stereocenter.

Impregnation of 12-tungstophosphoric acid on silica - part I: determination of impregnation parameters, characterization and evaluation of catalytic activity; Impregnacao do acido 12-fosfotungstico em silica - parte I: determinacao de parametros de impregnacao, caracterizacao e avaliacao da atividade catalitica

Energy Technology Data Exchange (ETDEWEB)

Scroccaro, Karine Isabel; Tanobe, Valcineide Oliveira de Andrade; Cocco, Lilian Cristina; Yamamoto, Carlos Itsuo, E-mail: karineisabel@yahoo.com.br [Universidade Federal do Parana, Curitiba, PR (Brazil). Centro Politecnico. Dept. de Engenharia Quimica; Wypych, Fernando [Universidade Federal do Parana, Curitiba, PR (Brazil). Centro Politecnico. Dept. de Quimica

2012-07-01

Catalyst based on Kegging-type heteropolyacids (H{sub 3}PW{sub 12}O{sub 40} - HPA), supported on SiO{sub 2} (H{sub 3}PW), were prepared by the impregnation method under different thermal treatment conditions. The materials were characterized by different instrumental techniques and used as catalysts in the methyl esterification reactions of stearic acid. Using the catalyst with 15% of HPA, conversions higher than 60% were obtained after 2 h of reaction at 65 deg C. Recovery studies using hot-filtration with ethanol at 75 deg C showed satisfactory activity for two additional reaction cycles. (author)

Impregnação do ácido 12-fosfotúngstico em sílica - parte I: determinação de parâmetros de impregnação, caracterização e avaliação da atividade catalítica

Directory of Open Access Journals (Sweden)

Karine Isabel Scroccaro

2012-01-01

Full Text Available Catalyst based on Kegging-type heteropolyacids (H3PW12O40 - HPA, supported on SiO2 (H3PW, were prepared by the impregnation method under different thermal treatment conditions. The materials were characterized by different instrumental techniques and used as catalysts in the methyl esterification reactions of stearic acid. Using the catalyst with 15% of HPA, conversions higher than 60% were obtained after 2 h of reaction at 65 ºC. Recovery studies using hot-filtration with ethanol at 75 ºC showed satisfactory activity for two additional reaction cycles.

Application of Heteropoly Acids as Heterogeneous and Recyclable Catalysts for Friedländer Synthesis of Quinolines

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Majid M. Heravi

2010-01-01

Full Text Available New convenient conditions for the Friedländer synthesis of quinolines are described. Quinolines were readily prepared in the presence of heteropolyacids as heterogeneous and recyclable catalysts in good yields.

Dual solid-phase and stir bar sorptive extraction combined with gas chromatography-mass spectrometry analysis provides a suitable tool for assaying limonene-derived mint aroma compounds in red wine.

Science.gov (United States)

Picard, Magali; Franc, Céline; de Revel, Gilles; Marchand, Stéphanie

2018-02-25

A novel analytical method was developed for quantitative determination of eight limonene-derived monoterpenes responsible for the mint aroma in red wine. As these aromatic compounds are present at trace levels, a new dual extraction approach was proposed, combining solid-phase extraction (SPE) and stir bar sorptive extraction (SBSE), followed by gas chromatography-mass spectrometry analysis. The various parameters affecting the efficiency of extracting the analytes from wine samples in both the SPE and SBSE steps were first investigated, to determine the best compromise for the simultaneous analysis of the compounds studied. Following preliminary optimization of the dilution factor, phase ratio, and methanol content in the SBSE sample, cartridge sorbent mass, type of solvent, elution volume, and wine sample volume in the pre-concentration SPE step were studied. Highest response values were obtained when a 90 mL wine sample was extracted on a 500 mg SPE C18 cartridge and eluted with 1.5 mL methanol. The wine extract was then diluted in 10 mL water to obtain a final methanol content of 15% before the SBSE step. Good linearity, repeatability, reproducibility, accuracy and the required low detection and quantification limits were obtained under the conditions described, making this SPE-SBSE combination a suitable, powerful tool for routine analysis of the selected limonene-derived mint aroma compounds in large series of wine samples. Finally, the validated method was applied to 15 commercial red Bordeaux wines, aged from 3 to 23 years. Most of the compounds studied, present within the ng.L -1 range, were easily quantified for the first time in wine. Copyright © 2017 Elsevier B.V. All rights reserved.

Bulletin of the Chemical Society of Ethiopia - Vol 28, No 1 (2014)

African Journals Online (AJOL)

Investigation of formation constant of complex of a new synthesized tripodal ligand with ... to synthesize spherical ZnSe nanoparticles: Appropriate templates for hollow ... Heteropolyacides as green and reusable catalysts for the synthesis of [3 ...

Ameliorative effects of gallic acid, quercetin and limonene on urethane-induced genotoxicity and oxidative stress in Drosophila melanogaster.

Science.gov (United States)

Nagpal, Isha; Abraham, Suresh K

2017-05-01

The main objective of our present work was to ascertain the efficacy of Drosophila melanogaster model for assessing antigenotoxic and antioxidant effects of dietary phytochemicals gallic acid (GA), quercetin (QC) and limonene (Lim) against urethane (URE), a genotoxic environmental carcinogen. Oregon-K (ORK) adult male flies were fed GA, QC and Lim in combination with URE (20 mM) in 10% sucrose for 72 h. Third instar larvae were fed instant medium containing the above phytochemicals and URE for 24 h. Sex-linked recessive lethal (SLRL) test and assays for estimating glutathione content (GSH), glutathione S-transferase (GST), catalase (CAT), superoxide dismutase (SOD) and lipid peroxidation (MDA content) were performed. Adult feeding experiments demonstrated that co-treatment of flies with URE and the test phytochemicals has significantly decreased the frequencies of SLRL mutations in all the germ cell stages when compared to that with URE alone. Larval feeding experiments also showed a similar pattern. The above results correlate well with antioxidative potentials of the test agents where we observed the elevated enzymatic levels with a significant reduction in MDA level in Drosophila larvae. The results further suggest that the dietary phytochemicals have an antioxidant and antimutagenic property which can be assessed using D. melanogaster.

Direct Activation Of Methane

KAUST Repository

Basset, Jean-Marie; Sun, Miao; Caps, Valerie; Pelletier, Jeremie; Abou-Hamad, Edy

2013-01-01

Heteropolyacids (HPAs) can activate methane at ambient temperature (e.g., 20.degree. C.) and atmospheric pressure, and transform methane to acetic acid, in the absence of any noble metal such as Pd). The HPAs can be, for example, those with Keggin

Effect of PW12–GPK on the acid characteristics of Ni-, Pd- and Pt- catalysts deposited onto pillared Al montmorillonite

Directory of Open Access Journals (Sweden)

D. Zhumadullaev

2012-03-01

Full Text Available Acid characteristics of Ni-, Pd-, Pt- catalyzers , deposited to Al pillared CaH montmorillonite modified by heteropolyacid H3PW12O40·xH2O (PW12 by ammonia thermoadsorbtion method has been studied.

Effect of reaction conditions on film morphology of polyaniline composite membranes for gas separation

KAUST Repository

Blinova, Natalia V.

2012-04-21

Composite membranes combining polyaniline as an active layer with a polypropylene support have been prepared using an in situ deposition technique. The protonated polyaniline layer with a thickness in the range of 90-200 nm was prepared using precipitation, dispersion, or emulsion polymerization of aniline with simultaneous deposition on top of the porous polypropylene support, which was immersed in the reaction mixture. Variables such as temperature, concentration of reagents, presence of steric stabilizers, surfactants, and heteropolyacid were found to control both the formation and the quality of the polyaniline layers. Both morphology and thickness of the layers were characterized using scanning electron microscopy. Selective separation of carbon dioxide from its mixture with methane is used to illustrate potential application of these composite membranes. © 2012 Wiley Periodicals, Inc.

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Indian Academy of Sciences (India)

Chitosan-based Schiff base-metal complexes (Mn, Cu, Co) as heterogeneous ... Acid concentration dependence ... Adsorption ..... Polymer supported nickel complex: Synthesis, structure ... Eco-friendly kinetic separation of trans-limonene and.

Pervaporation Separation of Water-Ethanol Mixtures Using Organic-Inorganic Nanocomposite Membranes

Science.gov (United States)

Preyssler type heteropolyacid viz., H14[NaP5W30O110] incorporated chitosan nanocomposite membranes (NCMs) were prepared by solution casting, characterized using a variety of techniques and employed in the pervaporation separation of water-ethanol mixtures as a function of feed wa...

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2008-10-31

2Depatrment of Chemistry, School of Sciences, Azad University, Khorasan Branch, Mashad,. Iran. (Received October 31, 2008; revised April 19, 2009). ABSTRACT. Keggin type of heteropolyacids as green reusable and efficient catalyst was used in the synthesis of benzoyl hydrazones from reaction of benzoic acid ...

Preparation of mesoporous Cs-POM@MOF-199@MCM-41 under two different synthetic methods for a highly oxidesulfurization of dibenzothiophene.

Science.gov (United States)

Li, Si-Wen; Li, Jia-Rong; Jin, Qi-Ping; Yang, Zhi; Zhang, Rong-Lan; Gao, Rui-Min; Zhao, Jian-She

2017-09-05

Two different synthetic methods, the direct method and the substitution method, were used to synthesize the Cs-POM@MOF-199@MCM-41 (Cs-PMM), in which the modified heteropolyacid with cesium salt has been encapsulated into the pores with the mixture of MOF and MCM-41. The structural properties of the as-prepared catalysts were characterized using various analytical techniques: powder X-ray diffraction, FT-IR, SEM, TEM, XPS and BET, confirming that the Cs-POM active species retained its Keggin structure after immobilization. The substitution method of Cs-PMM exhibited more excellent catalytic performance for oxidative desulfurization of dibenzothiophene in the presence of oxygen. Under optimal conditions, the DBT conversion rate reached up to 99.6% and could be recycled 10 times without significant loss of catalytic activity, which is mainly attributed to the slow leaching of the active heteropolyacid species from the strong fixed effect of the mixture porous materials. Copyright © 2017. Published by Elsevier B.V.

HETEROPOLYACIDES AS GREEN AND REUSABLE CATALYSTS ...

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phenacyl bromide in the presence of a catalytic amount of various .... The compounds 3 was characterised by NMR, IR spectroscopy and elemental analysis [40]. ... The present method does not involve any hazardous organic solvent.

Interaction of alcohols with the anhydrous silico-12-molybdic acid

International Nuclear Information System (INIS)

Pinchuk, I.N.; Chuvaev, V.F.; Ovchinnikova, N.S.; Zhuravlev, L.T.; Spitsyn, V.I.

1984-01-01

A study was made on interaction of methanol, ethanol and isopropanol with silico-12-molybdic acid (H 4 SiMo 12 O 40 (SMA). It was revealed that anhydrous SMA at room temperature adds a sufficient amount of alcohol from gaseous phase with formation of solvates of the following compositions: H 4 SiMo 12 O 40 x3CH 3 OH, H 4 SiMo 12 O 40 x5C 2 H 5 OH and H 4 SiMo 12 O 40 x3C 3 H 7 OH. Thermal decomposition of SMA solvates was studied and the mechanism of solid-phase heteropolyacid interaction with alcohols was suggested. Temperature ranges of separate catalytic and redox processes were established. Specificity of activity and peculiarities of heteropolyacid transformation in the course of reaction were investigated. It was shown that formation of deprotonated phases of SiMosub(12)Osub(38-y/2) or Csub(n)SiMosub(12)Osub(38-x) type during SMA interaction with alcohol can't be probably reduced to the simple succession of reduction and dehydration reactions

Effects of NOx and SO2 on the secondary organic aerosol formation from photooxidation of α-pinene and limonene

Science.gov (United States)

Zhao, Defeng; Schmitt, Sebastian H.; Wang, Mingjin; Acir, Ismail-Hakki; Tillmann, Ralf; Tan, Zhaofeng; Novelli, Anna; Fuchs, Hendrik; Pullinen, Iida; Wegener, Robert; Rohrer, Franz; Wildt, Jürgen; Kiendler-Scharr, Astrid; Wahner, Andreas; Mentel, Thomas F.

2018-02-01

Anthropogenic emissions such as NOx and SO2 influence the biogenic secondary organic aerosol (SOA) formation, but detailed mechanisms and effects are still elusive. We studied the effects of NOx and SO2 on the SOA formation from the photooxidation of α-pinene and limonene at ambient relevant NOx and SO2 concentrations (NOx: leading to a lack of particle surface for the organics to condense on and thus a significant influence of vapor wall loss on SOA mass yield. By compensating for the suppressing effect on nucleation of NOx, SO2 also compensated for the suppressing effect on SOA yield. Aerosol mass spectrometer data show that increasing NOx enhanced nitrate formation. The majority of the nitrate was organic nitrate (57-77 %), even in low-NOx conditions (nitrate contributed 7-26 % of total organics assuming a molecular weight of 200 g mol-1. SOA from α-pinene photooxidation at high NOx had a generally lower hydrogen to carbon ratio (H / C), compared to low NOx. The NOx dependence of the chemical composition can be attributed to the NOx dependence of the branching ratio of the RO2 loss reactions, leading to a lower fraction of organic hydroperoxides and higher fractions of organic nitrates at high NOx. While NOx suppressed new particle formation and SOA mass formation, SO2 can compensate for such effects, and the combining effect of SO2 and NOx may have an important influence on SOA formation affected by interactions of biogenic volatile organic compounds (VOCs) with anthropogenic emissions.

Solvates of silico-12-molybdic acid with alcohols

International Nuclear Information System (INIS)

Punchuk, I.N.; Chuvaev, V.F.

1984-01-01

With the aim of investigating interaction processes of solid heteropolyacids and organic compounds, solvates are prepared. Solvates are products of adding gaseous methanol, ethanol and isopropanol to silico-12-molybdic acid. The compounds are studied by IR and PMR spectroscopy methods. Possible models for solvate structure are considered, as well as their connection with solvate properties and thermal decomposition

Sensitive monitoring of monoterpene metabolites in human urine using two-step derivatisation and positive chemical ionisation-tandem mass spectrometry

International Nuclear Information System (INIS)

Schmidt, Lukas; Belov, Vladimir N.; Göen, Thomas

2013-01-01

Highlights: •Sensitive monitoring of 10 metabolites of (R)-limonene, α-pinene, and Δ 3 -carene in human urine samples. •Fast and simple sample preparation and derivatisation procedure using two-step silylation for unreactive tertiary hydroxyl groups. •Synthesis of reference substances and isotopically labelled internal standards of (R)-limonene, α-pinene, and Δ 3 -carene metabolites. •Study on (R)-limonene, α-pinene, and Δ 3 -carene metabolite background exposure of 36 occupationally unexposed volunteers. -- Abstract: A gas chromatographic–positive chemical ionisation-tandem mass spectrometric (GC–PCI-MS/MS) method for the simultaneous determination of 10 oxidative metabolites of the monoterpenoid hydrocarbons α-pinene, (R)-limonene, and Δ 3 -carene ((+)-3-carene) in human urine was developed and tested for the monoterpene biomonitoring of the general population (n = 36). The method involves enzymatic cleavage of the glucuronides followed by solid-supported liquid–liquid extraction and derivatisation using a two-step reaction with N,O-bis(trimethylsilyl)-trifluoroacetamide and N-(trimethylsilyl)imidazole. The method proved to be both sensitive and reliable with detection limits ranging from 0.1 to 0.3 μg L −1 . In contrast to the frequent and distinct quantities of (1S,2S,4R)-limonene-1,2-diol, the (1R,2R,4R)-stereoisomer could not be detected. The expected metabolite of (+)-3-carene, 3-caren-10-ol was not detected in any of the samples. All other metabolites were detected in almost all urine samples. The procedure enables for the first time the analysis of trace levels of a broad spectrum of mono- and bicyclic monoterpenoid metabolites (alcohols, diols, and carboxylic acids) in human urine. This analytical procedure is a powerful tool for population studies as well as for the discovery of human metabolism and toxicokinetics of monoterpenes

Sensitive monitoring of monoterpene metabolites in human urine using two-step derivatisation and positive chemical ionisation-tandem mass spectrometry

Energy Technology Data Exchange (ETDEWEB)

Schmidt, Lukas [Institute and Outpatient Clinic of Occupational, Social and Environmental Medicine, University of Erlangen-Nuremberg, Schillerstrasse 25/29, 91054 Erlangen (Germany); Belov, Vladimir N. [Max Planck Institute for Biophysical Chemistry, Facility for Synthetic Chemistry, Am Fassberg 11, 37077 Göttingen (Germany); Göen, Thomas, E-mail: Thomas.Goeen@ipasum.med.uni-erlangen.de [Institute and Outpatient Clinic of Occupational, Social and Environmental Medicine, University of Erlangen-Nuremberg, Schillerstrasse 25/29, 91054 Erlangen (Germany)

2013-09-02

Highlights: •Sensitive monitoring of 10 metabolites of (R)-limonene, α-pinene, and Δ{sup 3}-carene in human urine samples. •Fast and simple sample preparation and derivatisation procedure using two-step silylation for unreactive tertiary hydroxyl groups. •Synthesis of reference substances and isotopically labelled internal standards of (R)-limonene, α-pinene, and Δ{sup 3}-carene metabolites. •Study on (R)-limonene, α-pinene, and Δ{sup 3}-carene metabolite background exposure of 36 occupationally unexposed volunteers. -- Abstract: A gas chromatographic–positive chemical ionisation-tandem mass spectrometric (GC–PCI-MS/MS) method for the simultaneous determination of 10 oxidative metabolites of the monoterpenoid hydrocarbons α-pinene, (R)-limonene, and Δ{sup 3}-carene ((+)-3-carene) in human urine was developed and tested for the monoterpene biomonitoring of the general population (n = 36). The method involves enzymatic cleavage of the glucuronides followed by solid-supported liquid–liquid extraction and derivatisation using a two-step reaction with N,O-bis(trimethylsilyl)-trifluoroacetamide and N-(trimethylsilyl)imidazole. The method proved to be both sensitive and reliable with detection limits ranging from 0.1 to 0.3 μg L{sup −1}. In contrast to the frequent and distinct quantities of (1S,2S,4R)-limonene-1,2-diol, the (1R,2R,4R)-stereoisomer could not be detected. The expected metabolite of (+)-3-carene, 3-caren-10-ol was not detected in any of the samples. All other metabolites were detected in almost all urine samples. The procedure enables for the first time the analysis of trace levels of a broad spectrum of mono- and bicyclic monoterpenoid metabolites (alcohols, diols, and carboxylic acids) in human urine. This analytical procedure is a powerful tool for population studies as well as for the discovery of human metabolism and toxicokinetics of monoterpenes.

Indoor secondary organic aerosols formation from ozonolysis of monoterpene: An example of d-limonene with ammonia and potential impacts on pulmonary inflammations.

Science.gov (United States)

Niu, Xinyi; Ho, Steven Sai Hang; Ho, Kin Fai; Huang, Yu; Cao, Junji; Shen, Zhenxing; Sun, Jian; Wang, Xiumei; Wang, Yu; Lee, Shuncheng; Huang, Rujin

2017-02-01

Monoterpene is one class of biogenic volatile organic compounds (BVOCs) which widely presents in household cleaning products and air fresheners. It plays reactive role in secondary organic aerosols (SOAs) formation with ozone (O 3 ) in indoor environments. Such ozonolysis can be influenced by the presence of gaseous pollutants such as ammonia (NH 3 ). This study focuses on investigations of ozone-initiated formation of indoor SOAs with d-limonene, one of the most abundant indoor monoterpenes, in a large environmental chamber. The maximum total particle number concentration from the ozonolysis in the presence of NH 3 was 60% higher than that in the absence of NH 3 . Both of the nuclei coagulation and condensation involve in the SOAs growth. The potential risks of pulmonary injury for the exposure to the secondary particles formed were presented with the indexes of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and interleukin-10 (IL-10) expression levels in bronchoalveolar lavage fluid (BALF) upon intratracheal instillation in mice lung for 6 and 12h. The results indicated that there was 22-39% stronger pulmonary inflammatory effect on the particles generated with NH 3 . This is a pilot study which demonstrates the toxicities of the indoor SOAs formed from the ozonolysis of a monoterpene. Copyright © 2016 Elsevier B.V. All rights reserved.

SwissProt search result: AK104994 [KOME

Lifescience Database Archive (English)

Full Text Available AK104994 001-002-H11 (P11712) Cytochrome P450 2C9 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK070442 [KOME

Lifescience Database Archive (English)

Full Text Available AK070442 J023052E10 (P11712) Cytochrome P450 2C9 (EC 1.14.13.80) ((R)-limonene 6-mo...nooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase) (

SwissProt search result: AK067591 [KOME

Lifescience Database Archive (English)

Full Text Available AK067591 J013112H19 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK069701 [KOME

Lifescience Database Archive (English)

Full Text Available AK069701 J023027B10 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK104705 [KOME

Lifescience Database Archive (English)

Full Text Available AK104705 001-037-D08 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-...monooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK071743 [KOME

Lifescience Database Archive (English)

Full Text Available AK071743 J023111A19 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK119772 [KOME

Lifescience Database Archive (English)

Full Text Available AK119772 002-172-F03 (P11712) Cytochrome P450 2C9 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK106528 [KOME

Lifescience Database Archive (English)

Full Text Available AK106528 002-107-G06 (P11712) Cytochrome P450 2C9 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK240728 [KOME

Lifescience Database Archive (English)

Full Text Available AK240728 J043029C11 (P11712) Cytochrome P450 2C9 (EC 1.14.13.80) ((R)-limonene 6-mo...nooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase) (

SwissProt search result: AK119772 [KOME

Lifescience Database Archive (English)

Full Text Available AK119772 002-172-F03 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-...monooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK104825 [KOME

Lifescience Database Archive (English)

Full Text Available AK104825 001-041-F09 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-...monooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK243298 [KOME

Lifescience Database Archive (English)

Full Text Available AK243298 J100053J04 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK106068 [KOME

Lifescience Database Archive (English)

Full Text Available AK106068 001-206-H02 (P11712) Cytochrome P450 2C9 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK120674 [KOME

Lifescience Database Archive (English)

Full Text Available AK120674 J013161I12 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK067688 [KOME

Lifescience Database Archive (English)

Full Text Available AK067688 J013117E18 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK102040 [KOME

Lifescience Database Archive (English)

Full Text Available AK102040 J033081G24 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK120986 [KOME

Lifescience Database Archive (English)

Full Text Available AK120986 J023042H12 (P11712) Cytochrome P450 2C9 (EC 1.14.13.80) ((R)-limonene 6-mo...nooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase) (

SwissProt search result: AK120444 [KOME

Lifescience Database Archive (English)

Full Text Available AK120444 J013099E24 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK100766 [KOME

Lifescience Database Archive (English)

Full Text Available AK100766 J023119K20 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK104705 [KOME

Lifescience Database Archive (English)

Full Text Available AK104705 001-037-D08 (P11712) Cytochrome P450 2C9 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK101513 [KOME

Lifescience Database Archive (English)

Full Text Available AK101513 J033046E16 (P11712) Cytochrome P450 2C9 (EC 1.14.13.80) ((R)-limonene 6-mo...nooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase) (

SwissProt search result: AK069429 [KOME

Lifescience Database Archive (English)

Full Text Available AK069429 J023020M04 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK243687 [KOME

Lifescience Database Archive (English)

Full Text Available AK243687 J100090N22 (P11712) Cytochrome P450 2C9 (EC 1.14.13.80) ((R)-limonene 6-mo...nooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase) (

SwissProt search result: AK108382 [KOME

Lifescience Database Archive (English)

Full Text Available AK108382 002-142-E08 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-...monooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK106081 [KOME

Lifescience Database Archive (English)

Full Text Available AK106081 001-207-A08 (P11712) Cytochrome P450 2C9 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK105773 [KOME

Lifescience Database Archive (English)

Full Text Available AK105773 001-202-F01 (P11712) Cytochrome P450 2C9 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK120018 [KOME

Lifescience Database Archive (English)

Full Text Available AK120018 002-186-B11 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-...monooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK105993 [KOME

Lifescience Database Archive (English)

Full Text Available AK105993 001-205-H03 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-...monooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK105678 [KOME

Lifescience Database Archive (English)

Full Text Available AK105678 001-201-B02 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-...monooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK061878 [KOME

Lifescience Database Archive (English)

Full Text Available AK061878 001-041-B03 (P11712) Cytochrome P450 2C9 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK121238 [KOME

Lifescience Database Archive (English)

Full Text Available AK121238 J023096A02 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK107418 [KOME

Lifescience Database Archive (English)

Full Text Available AK107418 002-127-F04 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-...monooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK062535 [KOME

Lifescience Database Archive (English)

Full Text Available AK062535 001-104-F01 (P11712) Cytochrome P450 2C9 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK058424 [KOME

Lifescience Database Archive (English)

Full Text Available AK058424 001-015-D12 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-...monooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK066760 [KOME

Lifescience Database Archive (English)

Full Text Available AK066760 J013075G04 (P11712) Cytochrome P450 2C9 (EC 1.14.13.80) ((R)-limonene 6-mo...nooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase) (

SwissProt search result: AK242256 [KOME

Lifescience Database Archive (English)

Full Text Available AK242256 J075183D10 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK064920 [KOME

Lifescience Database Archive (English)

Full Text Available AK064920 J013000N03 (P11712) Cytochrome P450 2C9 (EC 1.14.13.80) ((R)-limonene 6-mo...nooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase) (

SwissProt search result: AK101670 [KOME

Lifescience Database Archive (English)

Full Text Available AK101670 J033058D07 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK069494 [KOME

Lifescience Database Archive (English)

Full Text Available AK069494 J023025F12 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK121124 [KOME

Lifescience Database Archive (English)

Full Text Available AK121124 J023074N24 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK060257 [KOME

Lifescience Database Archive (English)

Full Text Available AK060257 001-004-E10 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-...monooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK119569 [KOME

Lifescience Database Archive (English)

Full Text Available AK119569 002-117-A08 (P11712) Cytochrome P450 2C9 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK072163 [KOME

Lifescience Database Archive (English)

Full Text Available AK072163 J013131L23 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK065689 [KOME

Lifescience Database Archive (English)

Full Text Available AK065689 J013039G17 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK119264 [KOME

Lifescience Database Archive (English)

Full Text Available AK119264 001-130-A04 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-...monooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK099951 [KOME

Lifescience Database Archive (English)

Full Text Available AK099951 J013123G02 (P11712) Cytochrome P450 2C9 (EC 1.14.13.80) ((R)-limonene 6-mo...nooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase) (

SwissProt search result: AK100832 [KOME

Lifescience Database Archive (English)

Full Text Available AK100832 J023123D13 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK107584 [KOME

Lifescience Database Archive (English)

Full Text Available AK107584 002-130-E07 (P11712) Cytochrome P450 2C9 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK060257 [KOME

Lifescience Database Archive (English)

Full Text Available AK060257 001-004-E10 (P11712) Cytochrome P450 2C9 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK120674 [KOME

Lifescience Database Archive (English)

Full Text Available AK120674 J013161I12 (P11712) Cytochrome P450 2C9 (EC 1.14.13.80) ((R)-limonene 6-mo...nooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase) (

SwissProt search result: AK120987 [KOME

Lifescience Database Archive (English)

Full Text Available AK120987 J023042L02 (P11712) Cytochrome P450 2C9 (EC 1.14.13.80) ((R)-limonene 6-mo...nooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase) (

SwissProt search result: AK065238 [KOME

Lifescience Database Archive (English)

Full Text Available AK065238 J013002I04 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK070240 [KOME

Lifescience Database Archive (English)

Full Text Available AK070240 J023047K04 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK059235 [KOME

Lifescience Database Archive (English)

Full Text Available AK059235 001-024-E12 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-...monooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK059235 [KOME

Lifescience Database Archive (English)

Full Text Available AK059235 001-024-E12 (P11712) Cytochrome P450 2C9 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK065971 [KOME

Lifescience Database Archive (English)

Full Text Available AK065971 J013050H07 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK107034 [KOME

Lifescience Database Archive (English)

Full Text Available AK107034 002-121-B07 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-...monooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK059010 [KOME

Lifescience Database Archive (English)

Full Text Available AK059010 001-020-H10 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-...monooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK100964 [KOME

Lifescience Database Archive (English)

Full Text Available AK100964 J023142C08 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK120987 [KOME

Lifescience Database Archive (English)

Full Text Available AK120987 J023042L02 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK073618 [KOME

Lifescience Database Archive (English)

Full Text Available AK073618 J033050F23 (P33261) Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene 6-m...onooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase)

SwissProt search result: AK067458 [KOME

Lifescience Database Archive (English)

Full Text Available AK067458 J013107H17 (P11712) Cytochrome P450 2C9 (EC 1.14.13.80) ((R)-limonene 6-mo...nooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase) (

SwissProt search result: AK070167 [KOME

Lifescience Database Archive (English)

Full Text Available AK070167 J023042H13 (P11712) Cytochrome P450 2C9 (EC 1.14.13.80) ((R)-limonene 6-mo...nooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase) (

SwissProt search result: AK120700 [KOME

Lifescience Database Archive (English)

Full Text Available AK120700 J013170M24 (P11712) Cytochrome P450 2C9 (EC 1.14.13.80) ((R)-limonene 6-mo...nooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase) (

SwissProt search result: AK067847 [KOME

Lifescience Database Archive (English)

Full Text Available AK067847 J013124D03 (P11712) Cytochrome P450 2C9 (EC 1.14.13.80) ((R)-limonene 6-mo...nooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monooxygenase) (

UniProt search blastx result: AK288051 [KOME

Lifescience Database Archive (English)

Full Text Available AK288051 J075151F20 P33261|CP2CJ_HUMAN Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene... 6-monooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monoo

UniProt search blastx result: AK288730 [KOME

Lifescience Database Archive (English)

Full Text Available AK288730 J090063F11 P33261|CP2CJ_HUMAN Cytochrome P450 2C19 (EC 1.14.13.80) ((R)-limonene... 6-monooxygenase) (EC 1.14.13.48) ((S)-limonene 6-monooxygenase) (EC 1.14.13.49) ((S)-limonene 7-monoo

A detailed study on the working mechanism of a heteropoly acid modified TiO2 photoanode for efficient dye-sensitized solar cells.

Science.gov (United States)

Jiang, Yanxia; Yang, Yulin; Qiang, Liangsheng; Fan, Ruiqing; Li, Liang; Ye, Tengling; Na, Yong; Shi, Yan; Luan, Tianzhu

2015-03-14

A novel heteropolyacid (HPA) K6SiW11O39Ni(H2O)·xH2O (SiW11Ni) modified TiO2 has been successfully synthesized and introduced into the photoanode of dye-sensitized solar cells (DSSCs). The performance of the cell with the HPA-modified photoanode (SiW11Ni/TiO2), mixed with P25 powder in the ratio of 2 : 8, is better than the cell with a pristine P25 photoanode. An increase of 31% in the photocurrent and 22% improvement in the conversion efficiency are obtained. The effect of the heteropolyacid was well studied by UV-vis spectroscopy, spectro-electrochemical spectroscopy, dark current, intensity-modulated photocurrent spectroscopy and intensity-modulated photovoltage spectroscopy, open-circuit voltage decay and electrochemical impedance spectroscopy. The results show that the interfacial layer modified by SiW11Ni can enhance the injection and transport of electrons, and then retard the recombination of electrons, which results in a longer electron lifetime. What's more, the introduction of SiW11Ni can simultaneously broaden the absorption in the visible region, eventually leading to an efficient increase in energy conversion efficiency.

Similarities in STXM-NEXAFS Spectra of Atmospheric Particles and Secondary Organic Aerosol Generated from Glyoxal, α-Pinene, Isoprene, 1,2,4-Trimethylbenzene, and d-Limonene

Energy Technology Data Exchange (ETDEWEB)

Shakya, Kabindra M.; Liu, Shang; Takahama, Satoshi; Russell, Lynn M.; Keutsch, Frank N.; Galloway, Melissa M.; Shilling, John E.; Hiranuma, Naruki; Song, Chen; Kim, Hwajin; Paulson, Suazanne E.; Pfaffenberger, Lisa; Barmet, Peter; Slowik, J. G.; Prevot, A. S. H.; Dommen, J.; Baltensperger, Urs

2013-02-06

Functional group composition of particles produced in smog chambers are examined using scanning transmission X-ray microscopy (STXM) with near-edge X-ray absorption fine structure (NEXAFS) spectroscopy in order to identify characteristic spectral signatures for secondary organic aerosol (SOA). Glyoxal uptake studies showed absorption for mainly alkyl, carbon-nitrogen (C-N), and carboxylic carbonyl groups. The SOA formed from the photooxidation of α-pinene (with and without isoprene) showed stronger absorptions for alkyl and carbonyl groups than the glyoxal studies. The mass ratio of carbonyl to acid group was larger in α-pinene-only experiments relative to the mixed α-pinene-isoprene experiments. The chamber particle spectra were compared with the ambient particle spectra from multiple field campaigns to understand the potential SOA sources. One hundred nineteen particles from six field campaigns had spectral features that were considered similar to the chamber-SOA particles: MILAGRO-2006 (9 particles), VOCALS-2008 (42 particles), Whistler-2008 (22 particles), Scripps Pier-2009 (9 particles), Bakersfield-2010 (25 particles), and Whistler-2010 (12 particles). These similarities with SOA formed from glyoxal, α-pinene (with and without isoprene), 1,2,4-trimethylbenzene, and limonene provide spectroscopic evidence of SOA products from these precursors in ambient particles.

Multiphase composition changes and reactive oxygen species formation during limonene oxidation in the new Cambridge Atmospheric Simulation Chamber (CASC)

Science.gov (United States)

Gallimore, Peter J.; Mahon, Brendan M.; Wragg, Francis P. H.; Fuller, Stephen J.; Giorio, Chiara; Kourtchev, Ivan; Kalberer, Markus

2017-08-01

The chemical composition of organic aerosols influences their impacts on human health and the climate system. Aerosol formation from gas-to-particle conversion and in-particle reaction was studied for the oxidation of limonene in a new facility, the Cambridge Atmospheric Simulation Chamber (CASC). Health-relevant oxidising organic species produced during secondary organic aerosol (SOA) formation were quantified in real time using an Online Particle-bound Reactive Oxygen Species Instrument (OPROSI). Two categories of reactive oxygen species (ROS) were identified based on time series analysis: a short-lived component produced during precursor ozonolysis with a lifetime of the order of minutes, and a stable component that was long-lived on the experiment timescale (˜ 4 h). Individual organic species were monitored continuously over this time using Extractive Electrospray Ionisation (EESI) Mass Spectrometry (MS) for the particle phase and Proton Transfer Reaction (PTR) MS for the gas phase. Many first-generation oxidation products are unsaturated, and we observed multiphase aging via further ozonolysis reactions. Volatile products such as C9H14O (limonaketone) and C10H16O2 (limonaldehyde) were observed in the gas phase early in the experiment, before reacting again with ozone. Loss of C10H16O4 (7-hydroxy limononic acid) from the particle phase was surprisingly slow. A combination of reduced C = C reactivity and viscous particle formation (relative to other SOA systems) may explain this, and both scenarios were tested in the Pretty Good Aerosol Model (PG-AM). A range of characterisation measurements were also carried out to benchmark the chamber against existing facilities. This work demonstrates the utility of CASC, particularly for understanding the reactivity and health-relevant properties of organic aerosols using novel, highly time-resolved techniques.

Inorganic ion exchangers. Application to liquid effluent processing

International Nuclear Information System (INIS)

Dozol, M.

1983-10-01

Main inorganic ion exchangers used for radioactive liquid effluents presented in this report are: synthetic and natural zeolites, in titanium oxides, titanates, niobates, tantalates, zirconates, some insoluble salts of zirconium, molybdenum and tin, heteropolyacids and polyantimonic acid. Properties of these ion exchangers are described: structure, adsoption, radiation effects and thermal stability, application to waste processing, radioactive waste storage uranium and cesium 137 recovery are evoked [fr

Local and regional variation in the monoterpenes of ponderosa pine wood oleoresin

Science.gov (United States)

R.H. Smith; R.L. Peloquin; P.C. Passof

1969-01-01

A gas chromatographic analysis of the mono-terpenes of 927 ponderosa pines, representing to some degree a major portion of the species' range, showed considerable local and regional diversity in composition. Five major monoterpenes— α-pinene, β-pinene, 3-carene, myrcene, and limonene—were analyzed. There is some evidence to support the...

Decomposition of environmentally persistent perfluorooctanoic acid in water by photochemical approaches.

Science.gov (United States)

Hori, Hisao; Hayakawa, Etsuko; Einaga, Hisahiro; Kutsuna, Shuzo; Koike, Kazuhide; Ibusuki, Takashi; Kiatagawa, Hiroshi; Arakawa, Ryuichi

2004-11-15

The decomposition of persistent and bioaccumulative perfluorooctanoic acid (PFOA) in water by UV-visible light irradiation, by H202 with UV-visible light irradiation, and by a tungstic heteropolyacid photocatalyst was examined to develop a technique to counteract stationary sources of PFOA. Direct photolysis proceeded slowly to produce CO2, F-, and short-chain perfluorocarboxylic acids. Compared to the direct photolysis, H2O2 was less effective in PFOA decomposition. On the other hand, the heteropolyacid photocatalyst led to efficient PFOA decomposition and the production of F- ions and CO2. The photocatalyst also suppressed the accumulation of short-chain perfluorocarboxylic acids in the reaction solution. PFOA in the concentrations of 0.34-3.35 mM, typical of those in wastewaters after an emulsifying process in fluoropolymer manufacture, was completely decomposed by the catalyst within 24 h of irradiation from a 200-W xenon-mercury lamp, with no accompanying catalyst degradation, permitting the catalyst to be reused in consecutive runs. Gas chromatography/mass spectrometry (GC/MS) measurements showed no trace of environmentally undesirable species such as CF4, which has a very high global-warming potential. When the (initial PFOA)/(initial catalyst) molar ratio was 10: 1, the turnover number for PFOA decomposition reached 4.33 over 24 h of irradiation.

Natural abundance deuterium nuclear magnetic resonance spectroscopy: Study of the biosynthesis of monoterpenes

International Nuclear Information System (INIS)

Leopold, M.F.

1990-01-01

Deuterium NMR spectroscopy at natural abundance (D NMR-na) is a new technique for exploring the biosynthesis of small molecules such as monoterpenes. The analysis of relative site-specific deuterium integration values is an effective means of measuring isotope effects, and examining the regio- and stereochemistry of biosynthetic reactions. The deuterium integration values of linalyl acetate and limonene isolated from the same source were consistent and showed that proton abstraction from the postulated α-terpinyl cation intermediate to form limonene is regioselective from the methyl derived from the Cs methyl of the precursor, geranyl diphosphate. This regiochemistry was observed in limonene samples from different sources and the measured primary kinetic isotope effect ranged from 0.25 to in excess of 100 (no deuterium was removed within experimental error). Various α- and β-pinene samples were isolated and D NMR-na analysis showed evidence of isotopically sensitive partitioning of the pinylcation in the formation of these products. This spectral analysis supported published radiolabeling studies but did not require synthesis of substrates or enzyme purification. The formation of 3-carene occurs without isomerization of the double bond which was previously postulated. The olefinic deuterium of the bicyclic compound was traced to the depleted deuterium at C 2 of isopentyl diphosphate by D NMR-na data and this supported unpublished radiolabeling studies. Study of irregular monoterpenes, chrysanthemyl acetate and lyratyl acetate, showed partitioning of dimethylallyl diphosphate (DMAPP) by chrysanthemyl cyclase. The α-secondary kinetic isotope effect of 1.06-1.12, obtained from relative deuterium integration values, suggested that S N 1 ionization of one molecule of DMAPP is the first step in the condensation reaction

Evaluation of allergenicity of constituents of myoga using the murine local lymph node assay.

Science.gov (United States)

Wei, Q J; Wei, C N; Harada, K; Minamoto, K; Okamoto, Y; Otsuka, M; Ueda, A

2010-01-01

Myoga (Zingiber Myoga Roscoe) is a perennial plant with a pungent smell from its flower buds. It is native to East Asia and has been reported to cause allergic contact dermatitis. The purpose of this study is to assess the allergenicity of myoga related to its major chemical components, alpha-pinene, beta-pinene, limonene, limonene oxide and beta-phellandrene, which are supposed to be the causative agents of contact dermatitis among myoga cultivators. We performed a toxicity study of the volatile constituents of myoga using the local lymph node assay (LLNA), in which limonene, limonene oxide and beta-phellandrene had positive responses and the EC3 was 35.8%, 8.22%, and 0.54%, respectively. EC3 for both alpha-pinene and beta-pinene was over 100%. Both chemicals failed to induce positive responses in the LLNA. While the maximization rating of limonene, limonene oxide and phellandrene were evaluated as moderate, extreme, and extreme respectively, alpha-pinene and beta-pinene were evaluated as weak in the previously reported GPMT. The usage of LLNA was also confirmed by comparing with previously reported GPMT results to detect the allergenicity of myoga constituents. The actual risk of humans developing an allergy to myoga constituents depends on many factors. The concentration of the compounds, the frequency and duration of exposure and the condition of the skin are supposed to be important factors.

Decontaminating method for radioactive contaminant

International Nuclear Information System (INIS)

Suzuki, Ken-ichi.

1994-01-01

After decontamination of radioactive contaminates with d-limonene, a radioactive material separating agent not compatible with liquid wastes caused by decontamination is added to the liquid wastes. Then after stirring, they are stood still to be separated into two phases, and the radioactive materials in the liquid waste phase caused by decontamination are transferred to the phase of the radioactive material separating agent. With such procedures, they can satisfactorily be separated into two phases of d-limonene and the radioactive material separating agent. Further, d-limonene remaining after the separation can be used again as a decontaminating agent for radioactive contaminates. Therefore, the amount of d-limonene to be used can be reduced, to lower the cost for cleaning, thereby enabling to reduce the amount of radioactive wastes formed. (T.M.)

Hygroscopic properties and cloud condensation nuclei activation of limonene-derived organosulfates and their mixtures with ammonium sulfate

Science.gov (United States)

Hansen, A. M. K.; Hong, J.; Raatikainen, T.; Kristensen, K.; Ylisirniö, A.; Virtanen, A.; Petäjä, T.; Glasius, M.; Prisle, N. L.

2015-12-01

Organosulfates have been observed as constituents of atmospheric aerosols in a wide range of environments; however their hygroscopic properties remain uncharacterised. Here, limonene-derived organosulfates with a molecular weight of 250 Da (L-OS 250) were synthesised and used for simultaneous measurements with a hygroscopicity tandem differential mobility analyser (H-TDMA) and a cloud condensation nuclei counter (CCNC) to determine the hygroscopicity parameter, κ, for pure L-OS 250 and mixtures of L-OS 250 with ammonium sulfate (AS) over a wide range of humidity conditions. The κ values derived from measurements with H-TDMA decreased with increasing particle dry diameter for all chemical compositions investigated, indicating that κH-TDMA depends on particle diameter and/or surface effects; however, it is not clear if this trend is statistically significant. For pure L-OS 250, κ was found to increase with increasing relative humidity, indicating dilution/solubility effects to be significant. Discrepancies in κ between the sub- and supersaturated measurements were observed for L-OS 250, whereas κ of AS and mixed L-OS 250/AS were similar. This discrepancy was primarily ascribed to limited dissolution of L-OS 250 at subsaturated conditions. In general, hygroscopic growth factor, critical particle diameter and κ for the mixed L-OS 250/AS particles converged towards the values of pure AS for mixtures with ≥ 20 % w / w AS. Surface tension measurements of bulk aqueous L-OS 250/AS solutions showed that L-OS 250 was indeed surface active, as expected from its molecular structure, decreasing the surface tension of solutions with 24 % from the pure water value at a L-OS 250 concentration of 0.0025 mol L-1. Based on these surface tension measurements, we present the first concentration-dependent parametrisation of surface tension for aqueous L-OS 250, which was implemented to different process-level models of L-OS 250 hygroscopicity and CCN activation. The values of κ

NRI's research on radioactive wastes

International Nuclear Information System (INIS)

Alexa, J.; Dlouhy, Z.; Kepak, F.; Kourim, V.; Napravnik, J.; Razga, J.; Ralkova, J.; Uher, E.; Vojtech, O.

1976-01-01

A survey is given (including 41 references) of work carried out at the Nuclear Research Institute. Discussed are sorption processes (a selective sorbent for 90 Sr based on BaSO 4 , etc.), sorption on inorganic ion exchangers (heteropolyacid salts, ferrocyanides for 137 Cs capture), on organic cation exchangers (separation of lanthanides), electrocoagulation. The process is described of vitrification of highly radioactive wastes, the arrest of emissions, the deposition of radioactive wastes and surface decontamination. (M.K.)

Novel Oxidative Desulfurization of a Model Fuel with H2O2 Catalyzed by AlPMo12O40 under Phase Transfer Catalyst-Free Conditions

OpenAIRE

José da Silva, Márcio; Faria dos Santos, Lidiane

2013-01-01

A novel process was developed for oxidative desulfurization (ODS) in the absence of a phase transfer catalyst (PTC) using only Keggin heteropolyacids and their aluminum salts as catalysts. Reactions were performed in biphasic mixtures of isooctane/acetonitrile, with dibenzothiophene (DBT) as a model sulfur compound and hydrogen peroxide as the oxidant. Remarkably, only the AlPMo12O40-catalyzed reactions resulted in complete oxidation of DBT into DBT sulfone, which was totally extracted by ace...

Effects of electron beam irradiation on inorganic exchanger AMP

International Nuclear Information System (INIS)

Rao, K.L.N.; Mathew, C.; Deshpande, R.S.; Jadhav, A.V.; Pande, B.M.; Shukla, J.P.

1996-01-01

The heteropolyacid salt inorganic exchanger ammonium molybdophosphate (AMP) was subjected to an electron dose upto 2 MGy to assess any possible radiation damage. The breakthrough and total exchange capacity of AMP for Cs + from simulated fission product solutions were determined for both control and irradiated samples. The scanning electron microscopy (SEM) and energy dispersive x-ray analysis (EDX) were deployed to examine any marked microscopic changes taking place in this exchanger. (author). 3 refs., 3 figs

Toxic and hormetic-like effects of three components of citrus essential oils on adult Mediterranean fruit flies (Ceratitis capitata.

Directory of Open Access Journals (Sweden)

Stella A Papanastasiou

Full Text Available Plant essential oils (EOs and a wide range of their individual components are involved in a variety of biological interactions with insect pests including stimulatory, deterrent, toxic and even hormetic effects. Both the beneficial and toxic properties of citrus EOs on the Mediterranean fruit fly (medfly have been experimentally evidenced over the last years. However, no information is available regarding the toxic or beneficial effects of the major components of citrus EOs via contact with the adults of the Mediterranean fruit fly. In the present study, we explored the toxicity of limonene, linalool and α-pinene (3 of the main compounds of citrus EOs against adult medflies and identified the effects of sub-lethal doses of limonene on fitness traits in a relaxed [full diet (yeast and sugar] and in a stressful (sugar only feeding environment. Our results demonstrate that all three compounds inferred high toxicity to adult medflies regardless of the diet, with males being more sensitive than females. Sub-lethal doses of limonene (LD20 enhanced the lifespan of adult medflies when they were deprived of protein. Fecundity was positively affected when females were exposed to limonene sub-lethal doses. Therefore, limonene, a major constituent of citrus EOs, induces high mortality at increased doses and positive effects on life history traits of medfly adults through contact at low sub-lethal doses. A hormetic-like effect of limonene to adult medflies and its possible underlying mechanisms are discussed.

Activity of R(+) limonene on the maximum growth rate of fish spoilage organisms and related effects on shelf-life prolongation of fresh gilthead sea bream fillets.

Science.gov (United States)

Giarratana, Filippo; Muscolino, Daniele; Beninati, Chiara; Ziino, Graziella; Giuffrida, Alessandro; Panebianco, Antonio

2016-11-21

R(+)limonene (LMN) is the major aromatic compound in essential oils obtained from oranges, grapefruits, and lemons. The improvement of preservation techniques to reduce the growth and activity of spoilage microorganisms in foods is crucial to increase their shelf life and to reduce the losses due to spoilage. The aim of this work is to evaluate the effect of LMN on the shelf life of fish fillets. Its effectiveness was preliminarily investigated in vitro against 60 strains of Specific Spoilage Organisms (SSOs) and then on gilt-head sea bream fillets stored at 2±0.5°C for 15days under vacuum. LMN showed a good inhibitory effect against tested SSOs strains. On gilt-head sea bream fillets, LMN inhibited the growth SSOs effectively, and its use resulted in a shelf-life extension of ca. 6-9days of treated fillets, compared to the control samples. The LMN addition in Sparus aurata fillets giving a distinctive smell and like-lemon taste to fish fillets that resulted pleasant to panellists. Its use contributed to a considerable reduction of fish spoilage given that the fillets treated with LMN were still sensory acceptable after 15days of storage. LMN may be used as an effective antimicrobial system to reduce the microbial growth and to improve the shelf life of fresh gilt-head sea bream fillets. Copyright © 2016 Elsevier B.V. All rights reserved.

Monoterpene synthase from Dracocephalum kotschyi and SPME-GC-MS analysis of its aroma profile

Directory of Open Access Journals (Sweden)

S. Saeidnia

2014-04-01

Full Text Available Dracocephalum kotschyi (Lamiaceae, as one of the remarkable aromatic plants, widely grows and also is cultivated in various temperate regions of Iran. There are diverse reports about the composition of the oil of this plant representing limonene derivatives as its major compounds. There is no report on cloning of mono- or sesquiterpene synthases from this plant. In the present study, the aroma profile of D. kotschyi has been extracted and analyzed via Headspace Solid-Phase Microextraction technique coupled with Gas Chromatography- Mass Spectroscopy. In order to determine the sequence of the active terpene synthase in this plant, first mRNA was prepared and cloning was performed by 3’ and 5’-RACEs-PCR method, then cDNA was sequenced and finally aligned with other recognized terpene synthases. The results showed that the plant leaves mainly comprised geranial (37.2%, limonene-10-al (28.5%, limonene (20.1% and 1,1-dimethoxy decane (14.5%. Sequencing the cDNA cloned from this plant revealed the presence of a monoterpene synthase absolutely similar to limonene synthase, responsible in formation of limonene, terpinolene, camphene and some other cyclic monoterpenes in its young leaves.

REALCAT: A New Platform to Bring Catalysis to the Lightspeed

Directory of Open Access Journals (Sweden)

Paul Sébastien

2015-03-01

Full Text Available Catalysis, irrespective of its form can be considered as one of the most important pillars of today’s chemical industry. The development of new catalysts with improved performances is therefore a highly strategic issue. However, the a priori theoretical design of the best catalyst for a desired reaction is not yet possible and a time- and money-consuming experimental phase is still needed to develop a new catalyst for a given reaction. The REALCAT platform described in this paper consists in a complete, unique, integrated and top-level high-throughput technologies workflow that allows a significant acceleration of this kind of research. This is illustrated by some preliminary results of optimization of the operating conditions of glycerol dehydration to acrolein over an heteropolyacid-based supported catalyst. It is shown that using REALCAT high-throughput tools a more than 10-fold acceleration of the operating conditions optimization process is obtained.

Morphological transformation of soot: investigation of microphysical processes during the condensation of sulphuric acid and limonene ozonolysis products vapours

Science.gov (United States)

Pathak, R. K. P.; Pei, X.; Hallquist, M.; Pagels, J. H.

2017-12-01

Morphological transformation of soot particle by condensation of low volatility materials on it is a dominant atmospheric process with serious implications for its optical and hygroscopic properties, and atmospheric lifetime. In this study, the morphological transformation of soot agglomerate under the influence of condensation of vapours of sulphuric acid, and/or limonene ozonolysis products were investigated systematically using a Differential Mobility Analyser-Aerosol Particle Mass Analyser (DMA-APM) and the Tandem DMA techniques integrated with a laminar flow-tube system. We discovered that the morphology transformation of soot in general was a sequence of two-step process, i.e. (i) filling of void space within soot agglomerate; (ii) growth of particle diameter. These two steps followed and complimented each other. In the very beginning the filling was the dominant process followed by growth until it led to the accumulation of enough material that in turn exerted surface forces that eventually facilitated the further filling. The filling of void space was constrained by the initial morphology of fresh soot and the nature and amount of the material condensed. This process continued in several sequential steps until all void space within the soot agglomerate was filled completely and then growth of a spherical particle continued as long as mass was condensed on it. In this study, we developed a framework to quantify the microphysical transformation of soot upon the condensation of various materials. The framework utilized experimental data and hypothesis of ideal sphere growth and filling of voids to quantify the distribution of condensed materials in these two processes complimenting each other. Using this framework, we have quantified the percentage of material that went into processes of particle growth and void filling at each step. Using the same framework, we further estimated the fraction of internal voids and open voids and used this information to derive

Non-aqueous heavy oil extraction from oil sand

Energy Technology Data Exchange (ETDEWEB)

Bohnert, George [National Nuclear Security Administration (United States)

2011-07-01

The Kansas City plant operated by Honeywell has a long history of working with DOE NNSA on engineering and manufacturing services supporting national security requirements. The plant has developed a non-aqueous method for heavy oil extraction from oil sands. This method is environmentally friendly as it does not use any external body of water, which would normally be contaminated in the conventional method. It is a 2 phase process consisting of terpene, limonene or alpha pinene, and carbon dioxide. The CO2 and terpene phases are both closed loop systems which minimizes material loss. The limonene and alpha pinene are both naturally derived solvents that come from citrus sources or pine trees respectively. Carbon dioxide is an excellent co-solvent with terpene. There is also a possibility for heat loss recovery during the distillation phase. This process produces clean dry sand. Laboratory tests have concluded that this using non-aqueous liquids process works effectively.

Interaction of silico-12-molybdic acid with acetone

International Nuclear Information System (INIS)

Chuvaev, V.F.; Pinchuk, I.N.; Gubin, V.V.

1984-01-01

Methods of thermal analysis, mass-spectrometry, IR, PMR, ESR spectroscopy are used to investigate interaction processes of silico-12-molybdic acid H 4 SiMo 12 O 40 with acetone. Reactions in solution and with participation of solid heteropolyacid are studied. Organic products of catalytic and oxidation-reduction reactions are identified. The effect of conditions on the formation of different condensation and oxidation products and the sequence of appropriate reactions is discussed. Transformations of silico-12-molybolic acid are considered

78 FR 95 - Notice of Receipt of Requests for Amendments To Delete Uses in Certain Pesticide Registrations

Science.gov (United States)

2013-01-02

... Vegetables and Mangos. 82326-1 D-Limonene Limonene........ Outdoor Uses. Technical. Users of these products... for Amendments To Delete Uses in Certain Pesticide Registrations AGENCY: Environmental Protection... uses in certain pesticide registrations. FIFRA provides that a registrant of a pesticide product may at...

Impact of human presence on secondary organic aerosols derived from ozone-initiated chemistry in a simulated office environment

DEFF Research Database (Denmark)

Fadeyi, Moshood O.; Weschler, Charles J.; Tham, Kwok W.

2013-01-01

's reactions with various indoor pollutants. The present study examines this possibility for secondary organic aerosols (SOA) derived from ozone-initiated chemistry with limonene, a commonly occurring indoor terpene. The experiments were conducted at realistic ozone and limonene concentrations in a 240 m3...

Induction of apoptosis by Citrus paradisi essential oil in human leukemic (HL-60) cells.

Science.gov (United States)

Hata, Tomona; Sakaguchi, Ikuyo; Mori, Masahiro; Ikeda, Norikazu; Kato, Yoshiko; Minamino, Miki; Watabe, Kazuhito

2003-01-01

Limonene is a primary component of citrus essential oils (EOs) and has been reported to induce apoptosis on tumor cells. Little is known about induction of apoptosis by citrus EOs. In this study, we examined induction of apoptosis by Citrus aurantium var. dulcis (sweet orange) EO, Citrus paradisi (grapefruit) EO and Citrus limon (lemon) EO. These EOs induced apoptosis in HL-60 cells and the apoptosis activities were related to the limonene content of the EOs. Moreover, sweet orange EO and grapefruit EO may contain components besides limonene that have apoptotic activity. To identify the components with apoptotic activity, grapefruit EO was fractionated using silica gel columns, and the components were analyzed by GC-MS. The n-hexane fraction contained limonene, and the dichloromethane fraction (DF) contained aldehyde compounds and nootkatone. Decanal, octanal and citral in the DF showed strong apoptotic activity, suggesting that the aldehyde compounds induced apoptosis strongly in HL-60 cells.

Effects of NOx and SO2 on the secondary organic aerosol formation from photooxidation of α-pinene and limonene

Directory of Open Access Journals (Sweden)

D. Zhao

2018-02-01

Full Text Available Anthropogenic emissions such as NOx and SO2 influence the biogenic secondary organic aerosol (SOA formation, but detailed mechanisms and effects are still elusive. We studied the effects of NOx and SO2 on the SOA formation from the photooxidation of α-pinene and limonene at ambient relevant NOx and SO2 concentrations (NOx: < 1to 20 ppb, SO2: < 0.05 to 15 ppb. In these experiments, monoterpene oxidation was dominated by OH oxidation. We found that SO2 induced nucleation and enhanced SOA mass formation. NOx strongly suppressed not only new particle formation but also SOA mass yield. However, in the presence of SO2 which induced a high number concentration of particles after oxidation to H2SO4, the suppression of the mass yield of SOA by NOx was completely or partly compensated for. This indicates that the suppression of SOA yield by NOx was largely due to the suppressed new particle formation, leading to a lack of particle surface for the organics to condense on and thus a significant influence of vapor wall loss on SOA mass yield. By compensating for the suppressing effect on nucleation of NOx, SO2 also compensated for the suppressing effect on SOA yield. Aerosol mass spectrometer data show that increasing NOx enhanced nitrate formation. The majority of the nitrate was organic nitrate (57–77 %, even in low-NOx conditions (<  ∼  1 ppb. Organic nitrate contributed 7–26 % of total organics assuming a molecular weight of 200 g mol−1. SOA from α-pinene photooxidation at high NOx had a generally lower hydrogen to carbon ratio (H ∕ C, compared to low NOx. The NOx dependence of the chemical composition can be attributed to the NOx dependence of the branching ratio of the RO2 loss reactions, leading to a lower fraction of organic hydroperoxides and higher fractions of organic nitrates at high NOx. While NOx suppressed new particle formation and SOA mass formation, SO2 can compensate for such effects, and the

EKSTRAKSI MINYAK ATSIRI DAUN ZODIA (Evodia suaveolens DENGAN METODE MASERASI DAN DISTILASI AIR

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Prima Astuti Handayani

2014-10-01

Full Text Available Daun zodia merupakan tumbuhan yang berpotensi sebagai insektisida nabati. Daun zodia mengandung senyawa aktif limonene yang bersifat neurotoksin terhadap serangga. Pengambilan minyak atsiri daun zodia dilakuan dengan metode maserasi dan metode distilasi air. Pada metode maserasi bahan digunakan etanol dan dimaserasi selama 3x24 jam. Kemudian didistilasi untuk menguapkan pelarut etanol. Untuk metode distilasi air bahan didistilasi selama 3 jam, campuran minyak dan air dipisahkan dengan menambahkan pelarut n-heksana. Kemudian pelarut n-heksana dipisahkan dari minyak atsiri dengan cara direcovery menggunakan alat sokhlet. Minyak atsiri daun zodia yang dihasilkan dianalisis dengan Gas Cromatography-Mass Spectrometry (GC-MS untuk mengetahui kandungan senyawa kimianya. Hasil percobaan diperoleh randemen minyak atsiri daun zodia dengan metode maserasi sebesar 1,0566% dengan kandungan senyawa limonene 2,6%, sedangkan metode distilasi diperoleh randemen sebesar 0,6471% dengan kandungan senyawa limonene 1,26 %.Zodia leaf is a plant which has a potential to be plant-based insecticide. Zodia leaf has limonene as its active component which is neurotoxin towards insect. The extraction of the essential oil of the zodiac leaf is conducted using maceration method and water distillation method. In the maceration process, the raw material was macerated using ethanol for 72 hours, after that it was distillated to evaporate the ethanol. In the water distillated method, the raw material was distillated for 3 hours, the mixture of water and oil are separated by adding n-hexane solvent. After that, the n-hexane solvent was separated from the essential oil using recovery method using soxhlet. The obtained essential oil of zodia leaf was analyzed using GC-MS to determine its chemical component. The result of the research provides the yield of essential oil of zodiac leaf using maceration method is 1.0566% with limonene component is 2.6%, whereas the distillation method

In vitro antileishmanial and cytotoxicity activities of essential oils from Haplophyllum tuberculatum A. Juss leaves, stems and aerial parts.

Science.gov (United States)

Hamdi, Assia; Bero, Joanne; Beaufay, Claire; Flamini, Guido; Marzouk, Zohra; Vander Heyden, Yvan; Quetin-Leclercq, Joelle

2018-02-14

Plants used for traditional medicine produce diverse and complex secondary metabolites exhibiting various medicinal properties. The medicinal plant Haplophyllum tuberculatum is used by native people against malaria and parasitic infections. In this study and in order to contribute for the search of new natural drugs for leishmaniasis, the essential oils of H. tuberculatum leaves, stems and aerial parts (leaves+stems) collected in two different periods, 2013 and 2015, and their components by GC/FID and GC/MS analyses were investigated. Those collected in 2013 were also re-analyzed two years later. The extracted oils were screened in vitro for anti-leishmanial activity on Leishmania mexicana mexicana (L.m.m.) promastigotes and cytotoxicity on the Chinese Hamster Ovary (CHO) cell line. Limonene (1.5 - 8%), its isomers (R- (+)-limonene and S-(-)-limonene), linalool and octanol were also tested. Results showed that the chemical composition varied according to the year of collection. Though major compounds remain almost the same, qualitative and quantitative variations in the composition of the EOs can be observed between the two years of collection, with some minor compounds identified only in one type of samples. Variation in the composition were also observed in the re-analyzed volatile oils, showing stability concerns. The essential oils and R-(+)-limonene showed moderate anti-leishmanial activity. Their IC 50 range from 6.48 to 50.28 μg/ml. Cytotoxicity assays for theses volatile extracts, R- (+)-limonene and S- (-)-limonene on CHO cells showed relatively potent cytotoxicity with a selectivity index <10. Their CC 50 range from 27.79 to 82.56 μg/ml. The findings of the present study demonstrated that H. tuberculatum might not be considered as a natural source for production of new anti-leishmanial agents without further analyzing its eventual in vivo toxicity as well as that of major pure compounds.

Functionalities of chitosan conjugated with stearic acid and gallic acid and application of the modified chitosan in stabilizing labile aroma compounds in an oil-in-water emulsion.

Science.gov (United States)

Yang, Tsung-Shi; Liu, Tai-Ti; Lin, I-Hwa

2017-08-01

The aims of this research were to conjugate chitosan (CT) with stearic acid (SA) and gallic acid (GA), and apply the modified chitosan to stabilize labile aroma compounds such as allyl isothiocyanate (AITC) and limonene in oil-in-water emulsions. Generally, the antioxidant activity of CT-SA-GA increased as the GA content in the conjugate increased. In most assays, GA had a lower IC 50 value than that of CT-SA-GA; however, CT-SA-GA exhibited better performance than GA in the Fe 2+ -chelating activity. In accelerated tests (heating or illumination) for evaluating the chemical stability of AITC and limonene during storage, CT-SA and CT-SA-GA were used to prepare AITC and limonene O/W emulsions, respectively. Tween 80 and Span 80 (T-S-80), an emulsifier mixture, were used as a control in both emulsions for comparison. The results show that CT-SA or CT-SA-GA could protect AITC or limonene from degradation or oxidation more effectively than T-S-80. Copyright © 2017 Elsevier Ltd. All rights reserved.

An alternative process for hydrogenation of sunflower oil

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Rosana de Cassia de Souza Schneider

2010-12-01

Full Text Available Classic methodologies for hydrogenation of vegetable oils have traditionally been carried out by nickel catalysts under high pressure of H2 and high temperature. An alternative method for hydrogenation of sunflower oil using limonene and palladium-on-carbon was investigated in this study. The use of limonene as a hydrogen donor solvent was proposed in order to avoid high temperature and high-pressure conditions. The catalytic transfer of hydrogenation was studied by using 0.5 to 2% of Pd as a catalyst, a limonene:oil ratio of 3:1, and reaction times from 0.5 to 2 hours. Under these conditions, high selectivities for oleic acid and low concentrations of stearic acid were obtained.

Uso de materiales laminares tipo cobalto-molibdato como potenciales catalizadores en la transformación de limoneno

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Luz Palacio*

2009-12-01

Full Text Available Use of layered cobalt molybdate materials like potential catalysts in the transformation of limonene. Limonene catalytic transformation was carried-out with four cobalt and molybdenum-based materials: two ofthem were prepared by hydrothermal synthesis and co-precipitation, whereby layered materials were obtained (CoMox and CoMoy. The two remaining materials were obtained by means of calcination of the layered solids (CoMox500 y CoMoy350. The catalysts were characterized by X-ray Diffraction (XRD, Fourier Transformed Infrared Spectroscopy (FTIR, H2 Temperature-Programmed Reduction (TPR, Thermogravimetric Analysis (TGA, Differential Thermal Analysis (DTA and Atomic Absorption Spectroscopy (AAS. The better selectivity was 26% for limonene oxide with CoMox500

Self-diffusion nuclear magnetic resonance, microstructure transitions, and solubilization capacity of phytosterols and cholesterol in Winsor IV food-grade microemulsions

DEFF Research Database (Denmark)

Spernath, Aviram; Yaghmur, Anan; Aserin, Abraham

2003-01-01

Microemulsions are of growing interest to the food industry as vehicles for delivering and enhancing solubilization of natural food supplements with nutritional and health benefits. The incorporation of molecular phytosterols, cholesterol-lowering agents, in food products is of great interest...... to the food industry. In this work is demonstrated the use of water dilutable food-grade microemulsions consisting of ethoxylated sorbitan ester (Tween 60), water, R-(+)-limonene, ethanol, and propylene glycol as vehicles for enhancing the phytosterols solubilization. Phytosterols were solubilized up to 12...... times more than the dissolution capacity of the oil [R-(+)-limonene] for the same compounds. The solubilization capacity of phytosterols and cholesterol along a dilution line in a pseudo-ternary phase diagram [on this dilution line the weight ratio of R-(+)-limonene/ethanol/Tween 60 is constant at 1...

Chemical Diversity in Lippia alba (Mill. N. E. Brown Germplasm

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Arie Fitzgerald Blank

2015-01-01

Full Text Available The aim of this study was to perform chemical characterization of Lippia alba accessions from the Active Germplasm Bank of the Federal University of Sergipe. A randomized block experimental design with two replications was applied. The analysis of the chemical composition of the essential oils was conducted using a gas chromatograph coupled to a mass spectrometer. The chemical composition of the essential oils allowed the accessions to be allocated to the following six groups: group 1: linalool, 1,8-cineole, and caryophyllene oxide; group 2: linalool, geranial, neral, 1,8-cineol, and caryophyllene oxide; group 3: limonene, carvone, and sabinene; group 4: carvone, limonene, g-muurolene, and myrcene; group 5: neral, geranial, and caryophyllene oxide; and group 6: geranial, neral, o-cymene, limonene, and caryophyllene oxide.

The mobilies of chiral molecular cluster ions in He gas

International Nuclear Information System (INIS)

Saito, Kazuyuki; Matoba, Shiro; Koizumi, Tetsuo; Kojima, Takao M; Tanuma, Hajime; Shiromaru, Haruo

2012-01-01

We measured the mobilities of Li + -(2-butanol) and Li + -(limonene) ions in He gas at room temperature using a drift tube mass spectrometer. The zero field mobilities of Li + -(2-Butanol) and Li + -(Limonene) were much lower than the polarization limit, indicating that the geometric collision cross-sections between the cluster ions and He atom were larger than the cross-sections predicted by the presence of a polarization force alone.

Compositions of the volatile oils of Citrus macroptera and C. maxima.

Science.gov (United States)

Rana, Virendra S; Blazquez, Maria A

2012-10-01

The essential oils obtained by hydrodistillation from the fresh peels of Citrus macroptera Montr. and C. maxima (Burm.) Merr. were analyzed by GC and GC/MS. The yields of oil ranged from 0.53% in C. macroptera to 0.13% in C. maxima cultivar (white). Forty-seven compounds were identified in the oils with limonene (55.3-80.0%), dodecyl acrylate (2.2-8.0%), geranial (0.4-3.5%), trans-linalool oxide (1.0-2.8%), alpha-terpineol (0.7-2.3%), linalool (0.7-1.5%) and cis-linalool oxide (0.5-1.4%) identified as major compounds. The oil ofC. macroptera contained limonene (55.3%), beta-caryophyllene (4.7%) and geranial (3.5%) as main compounds. Similarly, oils from two C. maxima (pink and white) cultivars were rich in limonene (72.0-80.0%), dodecyl acrylate (8.0-7.2%) and nootkatone (1.6-2.5%). C. maxima (pink and white) cultivars were found to contain higher amount of limonene (72.0 and 80.0%) as compared with C. macroptera (55.3%). The chemical compositions of the oils were found to be similar, but nootkatone (1.6-2.5%) was identified only in C. maxima cultivars.

Essential oil composition of sixteen elite cultivars of Mentha from western Himalayan region, India

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Rajendra C. Padalia

2013-02-01

Full Text Available The hydrodistilled essential oils of 16 cultivars of Mentha, viz. M. arvensis L., M. spicata L. and M. citrata Ehrh., were analysed and compared by gas chromatography and gas chromatography-mass spectrometry. Fifty-seven constituents representing 92.8-99.8% of the total essential oil composition were identified. Monoterpenoids (88.1-98.6% are the major constituents of the essential oils. The major constituents of the oils in 9 cultivars of M. arvensis are menthol (73.7-85.8%, menthone (1.5-11.0%, menthyl acetate (0.5-5.3%, isomenthone (2.1-3.9%, limonene (1.2-3.3% and neomenthol (1.9-2.5%. Carvone (51.3-65.1%, limonene (15.1-25.2%, -pinene (1.3-3.2% and 1,8-cineole (≤0.1-3.6% are the major constituents in 5 cultivars of M. spicata, while in one cultivar (Ganga of M. spicata the major constituents are piperitenone oxide (76.7%, α-terpineol (4.9% and limonene (4.7%. Linalool (59.7%, linalyl acetate (18.4%, nerol (2.0%, trans-p-menth-1-en-2-ol (1.8%, a-terpineol (1.5% and limonene (1.1% are the major constituents of M. citrata.

Fumigant and repellent activities of essential oil extracted from Artemisia dubia and its main compounds against two stored product pests.

Science.gov (United States)

Liang, Jun-Yu; Guo, Shan-Shan; Zhang, Wen-Juan; Geng, Zhu-Feng; Deng, Zhi-Wei; Du, Shu-Shan; Zhang, Ji

2018-05-01

The major chemical constituents of the essential oil extracted from Artemisia dubia wall. ex Bess. (Family: Asteraceae) were found as terpinolene (19.02%), limonene (17.40%), 2,5-etheno[4.2.2]propella-3,7,9-triene (11.29%), isoelemicin (11.05%) and p-cymene-8-ol (5.93%). Terpinolene and limonene were separated as main components from the essential oil. The essential oil showed fumigant toxicity against Tribolium castaneum and Liposcelis bostrychophila with LC 50 values of 49.54 and 0.74 mg/L, respectively. The essential oil and isolated compounds of A. dubia showed repellency activities against both insects. Terpinolene and limonene showed the fumigant toxicity against T. castaneum. Terpinolene showed obvious fumigant toxicity against L. bostrychophila. The results indicated that the essential oil of A. dubia had potential to be developed into natural insecticides for controlling stored product pests.

Synthesis of tungstovanadophosphoric heteropolyacids and their behavior under high pressure

International Nuclear Information System (INIS)

Krasnoshchekov, V.V.; Morozova, P.P.

1985-01-01

By single-stage synthesis under elevated-pressures and temperatures (T=4 7 3 K, P=25000 atm) with 20-35% yield tungstovanadotophosphoric heteropoly acids (HPA) of different composition are prepared. The results of determining the compressibility, density and molecular volume of prepared HPA are given. It is shown that vanadium atoms introduction into tungstovanadium HPA molecule results in the decrease of density of the latter and increase of molar volumes

Fragrance encapsulation in polymeric matrices by emulsion electrospinning

OpenAIRE

Camerlo Agathe; Vebert-Nardin Corinne; Rossi René Michel; Popa Ana Maria

2013-01-01

We present the successful application of emulsion electrospinning for the encapsulation of a model for highly volatile fragrances namely (R) (+) limonene in a poly(vinyl alcohol) (PVA) fibrous matrix. The influence of the emulsion formulation and of its colloidal properties on the fiber morphology as well as on the limonene encapsulation efficiency is described. The release profile of the fragrance from the electrospun nanofibers over a fifteen days range shows that this type of nanofibrous m...

Thermodynamic study of selected monoterpenes III

International Nuclear Information System (INIS)

Štejfa, Vojtěch; Fulem, Michal; Růžička, Květoslav; Červinka, Ctirad

2014-01-01

Highlights: • (−)-trans-Pinane, (+)-Δ-carene, eucalyptol, and limonene were studied. • New thermodynamic data were measured and calculated. • Many of thermodynamic data are reported for the first time. - Abstract: A thermodynamic study of selected monoterpenes, (−)-trans-pinane, (+)-Δ-carene, eucalyptol, (+)-limonene, and (−)-limonene, is presented in this work. The vapor pressure measurements were performed using the static method over the environmentally important temperature range (238 to 308) K. Liquid heat capacities were measured by Tian–Calvet calorimetry in the temperature interval (258 to 355) K. The phase behavior was investigated by differential scanning calorimetry (DSC) from T = 183 K. The thermodynamic properties in the ideal-gas state were calculated by combining statistical thermodynamic and density functional theory (DFT) calculations. Calculated ideal-gas heat capacities and experimental data for vapor pressures and condensed phase heat capacities were treated simultaneously to obtain a consistent thermodynamic description

Recycling of pneumatic scrap tyre into nano-crumb rubber by pulsed laser ablation in different pH media

Science.gov (United States)

Ezaan Khamsan, Nur; Bidin, Noriah; Islam, Shumaila; Daud, Suzairi; Krishnan, Ganesan; Bakar, Mohamad Aizat A.; Naqiuddin Razali, Muhamad; Khamis, Jamil

2018-05-01

Nano crumb rubber from scrap tyre is synthesized via 1064 nm pulsed Nd:YAG laser ablation in three different pH media i.e. DI-water (pH∼6.45), D-limonene (pH∼3.47) and NaOH solution (pH∼13.41). Field Emission Scanning Electron Microscope (FESEM) results show spherical morphology of crumb rubber with high degree of aggregation in DI-water and in D-limonene. However, dispersion of crumb rubbers is observed in NaOH solution. The smallest particles size is obtained in NaOH solution within the range of 10.9 nm – 74.3 nm. Energy-dispersive X-ray spectroscopy (EDX) and FTIR analysis confirmed the elements distribution and chemical bonding of rubber with DI-water, D-limonene and NaOH solution. The experimental findings shows that pulsed Nd:YAG laser ablation has potential for fabricating nano-crumb rubber in liquid media.

Insecticidal Activity of Essential Oil of Carum Carvi Fruits from China and Its Main Components against Two Grain Storage Insects

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Shu Shan Du

2010-12-01

Full Text Available During our screening program for agrochemicals from Chinese medicinal herbs and wild plants, the essential oil of Carum carvi fruits was found to possess strong contact toxicity against Sitophilus zeamais and Tribolium castaneum adults, with LD50 values of 3.07 and 3.29 mg/adult, respectively, and also showed strong fumigant toxicity against the two grain storage insects with LC50 values of 3.37 and 2.53 mg/L, respectively. The essential oil obtained by hydrodistillation was investigated by GC and GC-MS. The main components of the essential oil were identified to be (R-carvone (37.98% and D-limonene (26.55% followed by α-pinene (5.21, cis-carveol (5.01% and b-myrcene (4.67%. (R-Carvone and D-limonene were separated and purified by silica gel column chromatography and preparative thin layer chromatography, and further identified by means of physicochemical and spectrometric analysis. (R-Carvone and D-limonene showed strong contact toxicity against S. zeamais (LD50 = 2.79 and 29.86 mg/adult and T. castaneum (LD50 = 2.64 and 20.14 mg/adult. (R-Carvone and D-limonene also possessed strong fumigant toxicity against S. zeamais (LC50 = 2.76 and 48.18 mg/L and T. castaneum adults (LC50 = 1.96 and 19.10 mg/L.

Selected oxidized fragrance terpenes are common contact allergens

DEFF Research Database (Denmark)

Matura, Mihaly; Sköld, Maria; Börje, Anna

2005-01-01

Terpenes are widely used fragrance compounds in fine fragrances, but also in domestic and occupational products. Terpenes oxidize easily due to autoxidation on air exposure. Previous studies have shown that limonene, linalool and caryophyllene are not allergenic themselves but readily form...... allergenic products on air-exposure. This study aimed to determine the frequency and characteristics of allergic reactions to selected oxidized fragrance terpenes other than limonene. In total 1511 consecutive dermatitis patients in 6 European dermatology centres were patch tested with oxidized fragrance...

Distillation of Essential Oils from Pontianak Orange Peel Wastes and Its Utilization for Aromatherapy Soap

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Hidayati Hidayati

2012-12-01

Full Text Available Orange (Citrus nobilis var. microcarpa is the main commodities in Pontianak. Production of essential oils from orange peel wastes and its use for soap aromatherapy substance could improve its economic value. This study is aimed to produce the essential oils from orange peel wastes with the highest limonene content by distillation. Its application for aromatherapy soap substance also evaluated. Distillation of essential oils from orange peels was performed at 1000C and 1100C for 4, 5, 6 and 7 hours. The results showed that at 1000C for 7 hours produced the highest limonene content, reach 97.69%. The essential oils color was pale yellow, specific gravity 0.84, refractive index 1.47, solubility in 90% ethanol 1:1 (transparent, acid value 0.143% and ester number 5.37. The aromatherapy soap produced with addition of 3.6% of limonene oils is in accordance with SNI 06-3532-1994 except for water content parameter.

Modeling the supercritical desorption of orange essential oil from a silica-gel bed

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Silva E.A.

2000-01-01

Full Text Available One of the most important byproducts of the orange juice industry is the oil phase. This is a mixture of terpenes, alcohols, and aldehydes, dissolved in approximately 96% limonene. To satisfactorily use oil phase as an ingredient in the food and cosmetics industries separation of the limonene is required. One possibility is to use a fixed bed of silica gel to remove the light or aroma compounds from the limonene. The aroma substances are then extracted from the bed of silica gel using supercritical carbon dioxide. This work deals with the modeling of the desorption step of the process using mass balance equations coupled with the Langmuir equilibrium isotherm. Data taken from the literature for the overall extraction curves were used together with empirical correlations to calculate the concentration profile of solute in the supercritical phase at the bed outlet. The system of equations was solved by the finite volume technique. The overall extraction curves calculated were in good agreement with the experimental ones.

Assessment of the risk of respiratory sensitization from fragrance allergens released by air fresheners.

Science.gov (United States)

ter Burg, Wouter; Bouma, Krista; Schakel, Durk J; Wijnhoven, Susan W P; van Engelen, Jacqueline; van Loveren, Henk; Ezendam, Janine

2014-04-01

Consumers using air fresheners are exposed to the emitted ingredients, including fragrances, via the respiratory tract. Several fragrances are known skin sensitizers, but it is unknown whether inhalation exposure to these chemicals can induce respiratory sensitization. Effects on the immune system were assessed by testing a selection of five fragrance allergens in the respiratory local lymph node assay (LLNA). The probability and extent of exposure were assessed by measuring concentrations of the 24 known fragrance allergens in 109 air fresheners. It was shown that the most frequently used fragrances in air fresheners were D-limonene and linalool. In the respiratory LLNA, these fragrances were negative. Of the other tested chemicals, only isoeugenol induced a statistically significant increase in cell proliferation. Consumer exposure was assessed in more detail for D-limonene, linalool, and isoeugenol by using exposure modeling tools. It was shown that the most frequently used fragrances in air fresheners, D-limonene, and linalool gave rise to a higher consumer exposure compared with isoeugenol. To evaluate whether the consumer exposure to these fragrances is low or high, these levels were compared with measured air concentrations of diisocyanates, known human respiratory sensitizers. This comparison showed that consumer exposure from air fresheners to D-limonene, linalool, and isoeugenol is considerably lower than occupational exposure to diisocyanates. By combing this knowledge on sensitizing potency with the much lower exposure compared to diisocyanates it seems highly unlikely that isoeugenol can induce respiratory sensitization in consumers using air fresheners.

Schistosomicidal Effects of the Essential Oils of Citrus limonia and Citrus reticulata Against Schistosoma mansoni.

Science.gov (United States)

Martins, Moara H G; Fracarolli, Letícia; Vieira, Tatiana M; Dias, Herbert J; Cruz, Michele G; Deus, Cássia C H; Nicolella, Heloiza D; Stefani, Ricardo; Rodrigues, Vanderlei; Tavares, Denise C; Magalhães, Lizandra G; Crotti, Antônio E M

2017-01-01

We report the in vitro schistosomicidal effects of the essential oil obtained from Citrus limonia leaves (CL-EO) and C. reticulata fruit peels (CR-EO), cultivated in Brazil, against Schistosoma mansoni worms. Limonene (29.9%), β-pinene (12.0%), sabinene (9.0%), citronellal (9.0%), and citronellol (5.8%) are the major constituents of CL-EO; limonene (26.5%), γ-terpinene (17.2%), linalool (11.1%), octanal (8.0%), myrcene (6.2%), and capraldehyde (3.9%) predominate in CR-EO. CL-EO displayed moderate lethal concentration 50% (LC 50 ) of 81.7 and 38.9 μg/ml against male and female worms at 24 and 72 h, respectively. At concentrations of 25 and 100 μg/ml, CL-EO separated between 50 and 75% of the coupled worm pairs during the evaluated period. CR-EO presented moderate LC 50 of 81.7 μg/ml against male and female worms at 24 and 72 h. However, this oil separated coupled worm pairs more effectively than CL-EO and displayed lower cytotoxicity to GM07492-A cells (IC 50 = 987.7 ± 88.9 μg/ml) as compared to CL-EO (IC 50 = 187.8 ± 2.9 μg/ml). The enantiomers (+)-(R)-limonene and (-)-(S)-limonene did not affect S. mansoni adult worm pairs significantly. Taken together, these data indicate that CL-EO and CR-EO exhibit moderate in vitro schistosomicidal activity against adult S. mansoni worms. © 2017 Wiley-VHCA AG, Zurich, Switzerland.

Non-mix fragrances are top sensitizers in consecutive dermatitis patients – a cross-sectional study of the 26 EU-labelled fragrance allergens

DEFF Research Database (Denmark)

Bennike, Niels H.; Zachariae, Claus; Johansen, Jeanne D.

2017-01-01

Background: For cosmetics, it is mandatory to label 26 fragrance substances, including all constituents of fragrance mix I (FM I) and fragrance mix II (FM II). Earlier reports have not included oxidized R-limonene [hydroperoxides of R-limonene (Lim-OOH)] and oxidized linalool [hydroperoxides...... patients were ‘FM II-negative but constituent-positive’ than ‘FM I-negative but constituent-positive’ (12.4% versus 3.2%, p = 0.0008). Conclusions: Non-mix fragrances are the most important single fragrance allergens among consecutive patients. The test concentration of the single FM I constituents should...

Photolysis of phenyldiazonium salts with heteropolyacid anions in aqueous organic media

International Nuclear Information System (INIS)

Kupletskaya, N.B.; Tikhonova, T.N.; Sagalovich, V.P.; Kazitsyna, L.A.

1983-01-01

Photochemical properties of phenyl-diazonium salts of n-XC 6 H 4 N 2 + Y - general formula, where X=EtN, CH 3 O, Br and Y - =PMo 12 O 40 -3 , PW 12 O 40 -3 are investigated. It is shown that in water-dimethylformamide mixture heteropolyanions during irradiation give heteropoly blues, which reduce diazonium cation and can be photosensitizers of phenyldiazonium salts decomposition. Substituted derivatives of phenyldiazonium salts are proposed to use for estimation of oxidizability of heteropoly blues. Quantum yields of decompositon of these salts in DMFA and CH 3 CN are determined; it is established that the heteropolyanion does not affect photosensitivity of the diazonium cation

Extraction method

International Nuclear Information System (INIS)

Stary, J.; Kyrs, M.; Navratil, J.; Havelka, S.; Hala, J.

1975-01-01

Definitions of the basic terms and of relations are given and the knowledge is described of the possibilities of the extraction of elements, oxides, covalent-bound halogenides and heteropolyacids. Greatest attention is devoted to the detailed analysis of the extraction of chelates and ion associates using diverse agents. For both types of compounds detailed conditions are given of the separation and the effects of the individual factors are listed. Attention is also devoted to extractions using mixtures of organic agents, the synergic effects thereof, and to extractions in non-aqueous solvents. The effects of radiation on extraction and the main types of apparatus used for extractions carried out in the laboratory are described. (L.K.)

Photometric determination of phosphorus in zircon concentrate and potassium hexafluorozirconate

International Nuclear Information System (INIS)

Polonskaya, I.A.; Fominykh, N.L.

1978-01-01

A method for direct photometric phosphorus determination in the materials, containing considerable zirconium amounts is developed. Phosphorus is determined in a form of reduced heteropolyacid with the use of ascorbic acid and potassium antimonyltartrate in sulfuric acid medium. To remove zirconium effect, a graduation diagram is drawn at the background of zirconium, which is bound into a stable fluoride complex in the presence of H 3 BO 3 . Under the above conditions the coloring developes after 30-40 min and remains stable for 24 hrs. A proportional dependence between phosphorus concentration and optical density is observed in the range of 10-160 mg of Zr. The method sensitivity is 5x10 -5 %

Synthesis of polyaniline nanotubes through UV light catalytic method

Directory of Open Access Journals (Sweden)

Chuanyu Sun

2015-03-01

Full Text Available In this study, nitrocellulose (NC fiber blanket prepared by electrostatic spinning method has been used as a template, and copper nitrate (Cu(NO32 as an oxidant to synthesise polyaniline nanotubes doped with heteropolyacid (H4SiW12O40, SiW12 using UV light catalytic method. Infrared spectroscopy (IR, X-ray powder diffraction (XRD, scanning electron microscopy (SEM and transmission electron microscopy (TEM technologies were applied to characterize the prepared samples of polyaniline nanotubes. The results show that the external diameter of the tube is about 200 nm, and the internal diameter about 170 nm. We also give a reasonable speculation and explanation about the formation mechanism of the nanotubes.

Chemical composition and antigenotoxic properties of Lippia alba essential oils

Directory of Open Access Journals (Sweden)

Molkary Andrea López

2011-01-01

Full Text Available The present work evaluated the chemical composition and the DNA protective effect of the essential oils (EOs from Lippia alba against bleomycin-induced genotoxicity. EO constituents were determined by Gas Chromatography/Mass Spectrometric (GC-MS analysis. The major compounds encountered being citral (33% geranial and 25% neral, geraniol (7% and trans-β-caryophyllene (7% for L. alba specimen COL512077, and carvone (38%, limonene (33% and bicyclosesquiphellandrene (8% for the other, COL512078. The genotoxicity and antigenotoxicity of EO and the compounds citral, carvone and limonene, were assayed using the SOS Chromotest in Escherichia coli. The EOs were not genotoxic in the SOS chromotest, but one of the major compound (limonene showed genotoxicity at doses between 97 and 1549 mM. Both EOs protected bacterial cells against bleomycin-induced genotoxicity. Antigenotoxicity in the two L. alba chemotypes was related to the major compounds, citral and carvone, respectively. The results were discussed in relation to the chemopreventive potential of L. alba EOs and its major compounds.

A low-energy, cost-effective approach to fruit and citrus peel waste processing for bioethanol production

International Nuclear Information System (INIS)

Choi, In Seong; Lee, Yoon Gyo; Khanal, Sarmir Kumar; Park, Bok Jae; Bae, Hyeun-Jong

2015-01-01

Highlights: • Simple bioprocess of bioethanol production from fruit wastes containing D-limonene. • Two in-house enzymatic bioconversion rates were approximately 90%. • Limonene recovery column (LRC) was designed for absorption of D-limonene. • Ethanol production by immobilized yeast fermentation and LRC was 12-fold greater. - Abstract: Large quantities of fruit waste are generated from agricultural processes worldwide. This waste is often simply dumped into landfills or the ocean. Fruit waste has high levels of sugars, including sucrose, glucose, and fructose, that can be fermented for bioethanol production. However, some fruit wastes, such as citrus peel waste (CPW), contain compounds that can inhibit fermentation and should be removed for efficient bioethanol production. We developed a novel approach for converting single-source CPW (i.e., orange, mandarin, grapefruit, lemon, or lime) or CPW in combination with other fruit waste (i.e., banana peel, apple pomace, and pear waste) to produce bioethanol. Two in-house enzymes were produced from Avicel and CPW and were tested with fruit waste at 12–15% (w/v) solid loading. The rates of enzymatic conversion of fruit waste to fermentable sugars were approximately 90% for all feedstocks after 48 h. We also designed a D-limonene removal column (LRC) that successfully removed this inhibitor from the fruit waste. When the LRC was coupled with an immobilized cell reactor (ICR), yeast fermentation resulted in ethanol concentrations (14.4–29.5 g/L) and yields (90.2–93.1%) that were 12-fold greater than products from ICR fermentation alone

Substantially Stabilized Superacid Incorporated SBA-15 with Calcium Bridging for Selective Esterification of Glycerol

Science.gov (United States)

Hoo, P. Y.; Abdullah, A. Z.; Shuit, S. H.; Teoh, Y. P.; Ng, Q. H.; Kunasundari, B.

2018-03-01

The exploitation of the super acidity of heteropolyacids incorporated heterogeneous catalysts was only feasible if the heterogeneity of these catalysts was assured. To maintain the catalyst heterogeneity in polar medium, a novel two-step modification method was proposed to synthesize the highly active, yet stable heterogeneous catalyst, catered for selective esterification of monoglyceride. The surficial, structural and acidity properties of the modified catalysts were investigated via crucial characterization methods (N2 BET, HRTEM, and FTIR). The collective evidences verified the predicted formation of calcium oxides (CaO) on the mesopores surfaces of the SBA-15 support after the first modification, and the successful subsequent 12-tungstophosphoric acid (HPW) functionalization. The superior stability of the synthesized catalysts (10wt%-HPW/CaSBA-15) was demonstrated (negligible change in both conversion – 75% and yield – 70%), without the need for catalyst regeneration. Such result was attributed to the strong interaction between HPW and SBA-15 via calcium bridging. Being alkaline in nature, calcium oxides in the inner pores readily reacted with highly acidic HPW introduced in the subsequent wetness incipient step, forming insoluble HPW acid sites on inner pore walls of SBA-15 via the calcium bridging. This modification deemed promising and other alkaline metals should be explored in the future.

Methyl isobutyl ketone (MIBK) induction of α2u-globulin nephropathy in male, but not female rats

International Nuclear Information System (INIS)

Borghoff, S.J.; Hard, G.C.; Berdasco, N.M.; Gingell, R.; Green, S.M.; Gulledge, W.

2009-01-01

Male F-344 rats were administered corn oil (vehicle control), d-limonene (positive control, 300 mg/kg), or MIBK (1000 mg/kg) and female F-344 rats corn oil (vehicle control) or MIBK for 10 consecutive days by oral gavage. Approximately 24 h after the final dose the kidneys were excised and the left kidney prepared and evaluated for histological changes including protein (hyaline) droplet accumulation, immunohistochemical staining for α2u-globulin (α2u), and proliferating cell nuclear antigen (PCNA) to quantitate renal cell proliferation. The right kidney was prepared for quantitation of total protein and α2u using an ELISA. MIBK elicited an increase in protein droplets, accumulation of α2u, and renal cell proliferation in male, but not female rats, responses characteristic of α2u-mediated nephropathy. MIBK produced identical histopathological changes in the male rat kidney when compared to d-limonene, an acknowledged inducer of α2u-nephropathy except that the grade of severity tended to be slightly lower with MIBK. MIBK did not induce any effects in female rats. Therefore, renal histopathology, along with the other measures of α2u accumulation, provides additional weight of evidence to support the inclusion of MIBK in the category of chemicals exerting renal effects through a α2u-nephropathy-mediated mode-of-action

Mechanistic and kinetic insights into the thermally induced rearrangement of alpha-pinene.

Science.gov (United States)

Stolle, Achim; Ondruschka, Bernd; Findeisen, Matthias

2008-11-07

The thermal rearrangement of alpha-pinene (1) is interesting from mechanistic as well as kinetic point of view. Carrier gas pyrolyses with 1 and its acyclic isomers ocimene (2) and alloocimene (3) were performed to investigate the thermal network of these hydrocarbons. Kinetic analysis of the major reaction steps allows for a deeper insight in the reaction mechanism. Thus it was possible to explain the racemization of 1, the formation of racemic limonene (4), and the absence of the primary pyrolysis product 2 in the reaction mixture resulting from thermal rearrangement of 1. Results supported the conclusion that the reactions starting with 1 involve biradical transition states.

Biodiesel production from the lipid of wastewater sludge using an acidic heterogeneous catalyst

Energy Technology Data Exchange (ETDEWEB)

Siddiquee, M.N.; Kazemian, H.; Rohani, S. [University of Western Ontario, Department of Chemical and Biochemical Engineering, London, ON (Canada)

2011-12-15

The production of biodiesel from the lipid of wastewater sludge was studied using SBA-15 impregnated with the heteropolyacid H{sub 3}PO{sub 4}.12WO{sub 3}.xH{sub 2}O (PW{sub 12}) as a mesoporous heterogeneous catalyst. X-ray diffraction, Brunauer-Emmett-Teller surface area, thermalgravimetric analysis, and scanning electron microscopy were applied to characterize the prepared catalysts. Catalytic performances were evaluated in a microreactor setup under different experimental conditions. The biodiesel yield for a sample impregnated with 15 % PW{sub 12} was 30.14 wt-% at a temperature of 135 C and a pressure of 135 psi for 3 h reaction time. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Fragrance ingredient labelling in products on sale in the U.K.

Science.gov (United States)

Buckley, D A

2007-08-01

The seventh amendment of the European Union (EU) Cosmetics Directive (March 2005) and the Detergents Regulations of the EU (October 2005) are now legal requirements in Europe. Cosmetic products and detergents must be labelled for 26 individual named fragrances, when present at concentrations of > 10 parts per million (p.p.m.) in leave-on products and > 100 p.p.m. in rinse-off products. To make an assessment of the exposure pattern to fragrance of the U.K. consumer and to determine the frequency with which the constituent fragrances of fragrance mix I (FM I) and fragrance mix II (FM II) are included in products currently sold in the U.K. A study of perfumed cosmetic and household products available on the shelves of U.K. retailers was carried out in January 2006. Products were included if 'parfum' or 'aroma' was listed among the ingredients. Three hundred products were surveyed and any of the 26 listed fragrances named on the label were recorded. The top six most frequently labelled fragrances were linalool (190; 63%), limonene (189; 63%), citronellol (145; 48%), geraniol (126; 42%), butyl phenyl methyl propional (Lilial(trade mark)) (126; 42%) and hexyl cinnamal (125; (42%). One of these, geraniol, is present in FM I and two others, citronellol and hexyl cinnamal, in FM II, thus tested as part of the British Standard patch test series. The frequencies of other constituents of FM I were as follows: eugenol, 80 (27%); hydroxycitronellal, 52 (17%); isoeugenol, 27 (9%); cinnamic alcohol, 25 (8%); amyl cinnamal, 22 (7%); cinnamal, 17 (6%); Evernia prunastri (oak moss absolute), 13 (4%). The other constituents of FM II occurred as follows: coumarin, 90 (30%); hydroxyisohexyl-3-cyclohexene carboxaldehyde (Lyral(trade mark)), 88 (29%); citral, 74 (25%); farnesol, 23 (8%). Linalool (n = 46; 66%) was the most frequently found fragrance in 70 personal care products (soap, shampoo, shower gel). Linalool (n = 47; 80%) and limonene (n = 45; 76%) were the most frequent in 59

An efficient route to selective bio-oxidation catalysts: an iterative approach comprising modeling, diversification, and screening, based on CYP102A1.

Science.gov (United States)

Seifert, Alexander; Antonovici, Mihaela; Hauer, Bernhard; Pleiss, Jürgen

2011-06-14

Perillyl alcohol is the terminal hydroxylation product of the cheap and readily available terpene, limonene. It has high potential as an anti-tumor substance, but is of limited availability. In principle, cytochrome P450 monooxygenases, such as the self-sufficient CYP102A1, are promising catalysts for the oxidation of limonene or other inert hydrocarbons. The wild-type enzyme converts (4R)-limonene to four different oxidation products; however, terminal hydroxylation at the allylic C7 is not observed. Here we describe a generic strategy to engineer this widely used enzyme to hydroxylate exclusively the exposed, but chemically less reactive, primary C7 in the presence of other reactive positions. The approach presented here turns CYP102A1 into a highly selective catalyst with a shifted product spectra by successive rounds of modeling, the design of small focused libraries, and screening. In the first round a minimal CYP102A1 mutant library was rationally designed. It contained variants with improved or strongly shifted regio-, stereo- and chemoselectivity, compared to wild-type. From this library the variant with the highest perillyl alcohol ratio was fine-tuned by two additional rounds of molecular modeling, diversification, and screening. In total only 29 variants needed to be screened to identify the triple mutant A264V/A238V/L437F that converts (4R)-limonene to perillyl alcohol with a selectivity of 97 %. Focusing mutagenesis on a small number of relevant positions identified by computational approaches is the key for efficient screening for enzyme selectivity. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Synergistic combinations of high hydrostatic pressure and essential oils or their constituents and their use in preservation of fruit juices.

Science.gov (United States)

Espina, Laura; García-Gonzalo, Diego; Laglaoui, Amin; Mackey, Bernard M; Pagán, Rafael

2013-01-15

This work addresses the inactivation achieved with Escherichia coli O157:H7 and Listeria monocytogenes EGD-e by combined processes of high hydrostatic pressure (HHP) and essential oils (EOs) or their chemical constituents (CCs). HHP treatments (175-400 MPa for 20 min) were combined with 200 μL/L of each EO (Citrus sinensis L., Citrus lemon L., Citrus reticulata L., Thymus algeriensis L., Eucalyptus globulus L., Rosmarinus officinalis L., Mentha pulegium L., Juniperus phoenicea L., and Cyperus longus L.) or each CC ((+)-limonene, α-pinene, β-pinene, p-cymene, thymol, carvacrol, borneol, linalool, terpinen-4-ol, 1,8-cineole, α-terpinyl acetate, camphor, and (+)-pulegone) in buffer of pH 4.0 or 7.0. The tested combinations achieved different degrees of inactivation, the most effective being (+)-limonene, carvacrol, C. reticulata L. EO, T. algeriensis L. EO and C. sinensis L. EO which were capable of inactivating about 4-5 log(10) cycles of the initial cell populations in combination with HHP, and therefore showed outstanding synergistic effects. (+)-Limonene was also capable of inactivating 5 log(10) cycles of the initial E. coli O157:H7 population in combination with HHP (300 MPa for 20 min) in orange and apple juices, and a direct relationship was established between the inactivation degree caused by the combined process with (+)-limonene and the occurrence of sublethal injury after the HHP treatment. This work shows the potential of EOs and CCs in the inactivation of foodborne pathogens in combined treatments with HHP, and proposes their possible use in liquid food such as fruit juices. Copyright © 2012 Elsevier B.V. All rights reserved.

Encapsulation of Polymethoxyflavones in Citrus Oil Emulsion-Based Delivery Systems.

Science.gov (United States)

Yang, Ying; Zhao, Chengying; Chen, Jingjing; Tian, Guifang; McClements, David Julian; Xiao, Hang; Zheng, Jinkai

2017-03-01

The purpose of this work was to elucidate the effects of citrus oil type on polymethoxyflavone (PMF) solubility and on the physicochemical properties of PMF-loaded emulsion-based delivery systems. Citrus oils were extracted from mandarin, orange, sweet orange, and bergamot. The major constituents were determined by GC/MS: sweet orange oil (97.4% d-limonene); mandarin oil (72.4% d-limonene); orange oil (67.2% d-limonene); and bergamot oil (34.6% linalyl acetate and 25.3% d-limonene). PMF-loaded emulsions were fabricated using 10% oil phase (containing 0.1% w/v nobiletin or tangeretin) and 90% aqueous phase (containing 1% w/v Tween 80) using high-pressure homogenization. Delivery systems prepared using mandarin oil had the largest mean droplet diameters (386 or 400 nm), followed by orange oil (338 or 390 nm), bergamot oil (129 or 133 nm), and sweet orange oil (122 or 126 nm) for nobiletin- or tangeretin-loaded emulsions, respectively. The optical clarity of the emulsions increased with decreasing droplet size due to reduced light scattering. The viscosities of the emulsions (with or without PMFs) were similar (1.3 to 1.4 mPa·s), despite appreciable differences in oil phase viscosity. The loading capacity and encapsulation efficiency of the emulsions depended on carrier oil type, with bergamot oil giving the highest loading capacity. In summary, differences in the composition and physical characteristics of citrus oils led to PMF-loaded emulsions with different encapsulation and physicochemical characteristics. These results will facilitate the rational design of emulsion-based delivery systems for encapsulation of PMFs and other nutraceuticals in functional foods and beverages.

Deterpenation of eucalyptus essential oil by liquid + liquid extraction: Phase equilibrium and physical properties for model systems at T = 298.2 K

International Nuclear Information System (INIS)

Gonçalves, Daniel; Koshima, Cristina Chiyoda; Nakamoto, Karina Thiemi; Umeda, Thayla Karla; Aracava, Keila Kazue; Gonçalves, Cintia Bernardo; Rodrigues, Christianne Elisabete da Costa

2014-01-01

Highlights: • Fractionation of essential oil compounds. • Liquid + liquid equilibria of limonene, citronellal, ethanol and water were studied. • Distribution coefficients of limonene and citronellal were evaluated. • Densities and viscosities of the phases were experimentally determined. • Solvent selectivities and physical properties were dependent on citronellal and water mass fractions. -- Abstract: As the principal source in Brazil of eucalyptus essential oil extracts, Eucalyptus citriodora contains citronellal, an oxygenated compound responsible for the flavour characteristics. Deterpenation processes, consisting of the removal of terpenic hydrocarbons with the subsequent concentration of the oxygenated compounds, can be used to improve the aromatic characteristics of this essential oil. The purpose of this work was to perform a study of the technical feasibility of using a liquid + liquid extraction process to deterpenate eucalyptus essential oil. Model systems with various mixtures of limonene and citronellal (representing eucalyptus essential oil) as well as solvent (ethanol with various water mass fractions) were used to obtain liquid + liquid equilibrium data. The raffinate and extract phases were also analyzed to characterize the physical properties (density and viscosity). The equilibrium data were used to adjust the NRTL and UNIQUAC parameters. Two empirical models, the simple mixing rule and the Grunberg–Nissan model, were evaluated for use in the descriptions of the densities and viscosities, respectively, of the samples. Increasing the water content in the solvent resulted in decreases in the limonene and citronellal distribution coefficients, with consequential increases in the solvent selectivity values. Increasing values of the densities and viscosities, especially for the solvent-rich phases, were associated with systems using high amounts of hydrated ethanolic solvents

Pros and cons of analytical methods to quantify surrogate contaminants from the challenge test in recycled polyethylene terephthalate

Energy Technology Data Exchange (ETDEWEB)

Felix, Juliana S., E-mail: jfelix@unizar.es [Department of Analytical Chemistry, Aragon Institute of Engineering Research (I3A), CPS, University of Zaragoza, Torres Quevedo Bldg., Maria de Luna St. 3, E-50018 Zaragoza (Spain); Alfaro, Pilar, E-mail: palfarot@unizar.es [Department of Analytical Chemistry, Aragon Institute of Engineering Research (I3A), CPS, University of Zaragoza, Torres Quevedo Bldg., Maria de Luna St. 3, E-50018 Zaragoza (Spain); Nerin, Cristina, E-mail: cnerin@unizar.es [Department of Analytical Chemistry, Aragon Institute of Engineering Research (I3A), CPS, University of Zaragoza, Torres Quevedo Bldg., Maria de Luna St. 3, E-50018 Zaragoza (Spain)

2011-02-14

Different analytical methods were optimized and applied to quantify certain surrogate contaminants (toluene, chlorobenzene, phenol, limonene and benzophenone) in samples of contaminated and recycled flakes and virgin pellets of polyethylene terephthalate (PET) coming from the industrial challenge test. A screening analysis of the PET samples was carried out by direct solid-phase microextraction (SPME) in headspace mode (HS). The methods developed and used for quantitative analysis were a) total dissolution of PET samples in dichloroacetic acid and analysis by HS-SPME coupled to gas chromatography-mass spectrometry (GC-MS) and, b) dichloromethane extraction and analysis by GC-MS. The concentration of all surrogates in the contaminated PET flakes analyzed by HS-SPME method was lower than expected according to information provided by the supplier. Dichloroacetic acid interacted with the surrogates, resulting in a tremendous decrease of limonene concentration. The degradation compounds from limonene were identified. Dichloromethane extraction and GC-MS analysis evidenced the highest values of analytes in these PET samples. Based on the foregoing data, the efficiency of the recycling process was evaluated, whereby the removal of 99.9% of the surrogates proceeding from the contaminated flakes was confirmed.

Compositional Shift in Fatty Acid Profiles of Lipids Obtained from Oleaginous Yeasts upon the Addition of Essential Oil from Citrus sinensis L.

Science.gov (United States)

Uprety, Bijaya K; Rakshit, Sudip K

2017-12-01

Tailoring lipids from oleaginous yeasts to contain specific types of fatty acid is of considerable interest to food, fuel, and pharmaceutical industries. In this study, the essential oil obtained from Citrus sinesus L. has been used to alter the fatty acid composition of two common oleaginous yeasts, Rhodosporidium toruloides and Cryptococcus curvatus. With increasing levels of essential oil in the medium, the metabolic flux of the fatty acid biosynthesis pathway shifted towards saturated fatty acid production. Essential oil reduced the activities of elongase and ∆9 desaturase. This made the lipid obtained from both these yeasts rich in saturated fatty acids. At certain specific concentrations of the essential oil in the medium, the lipid obtained from R. toruloides and C. curvatus cultures was similar to mahuwa butter and palm oil, respectively. Limonene is the major constituents of orange essential oil. Its effect on one of the oleaginous yeasts, R. toruloides, was also studied separately. Effects similar to orange essential oil were obtained with limonene. Thus, we can conclude that limonene in orange essential oil brings about compositional change of microbial lipid produced in this organism.

Pros and cons of analytical methods to quantify surrogate contaminants from the challenge test in recycled polyethylene terephthalate

International Nuclear Information System (INIS)

Felix, Juliana S.; Alfaro, Pilar; Nerin, Cristina

2011-01-01

Different analytical methods were optimized and applied to quantify certain surrogate contaminants (toluene, chlorobenzene, phenol, limonene and benzophenone) in samples of contaminated and recycled flakes and virgin pellets of polyethylene terephthalate (PET) coming from the industrial challenge test. A screening analysis of the PET samples was carried out by direct solid-phase microextraction (SPME) in headspace mode (HS). The methods developed and used for quantitative analysis were a) total dissolution of PET samples in dichloroacetic acid and analysis by HS-SPME coupled to gas chromatography-mass spectrometry (GC-MS) and, b) dichloromethane extraction and analysis by GC-MS. The concentration of all surrogates in the contaminated PET flakes analyzed by HS-SPME method was lower than expected according to information provided by the supplier. Dichloroacetic acid interacted with the surrogates, resulting in a tremendous decrease of limonene concentration. The degradation compounds from limonene were identified. Dichloromethane extraction and GC-MS analysis evidenced the highest values of analytes in these PET samples. Based on the foregoing data, the efficiency of the recycling process was evaluated, whereby the removal of 99.9% of the surrogates proceeding from the contaminated flakes was confirmed.

REPELLENT AND OVIPOSITION DETERRENT ACTIVITIES OFTHE ESSENTIAL OIL FROM MIKANIA MICRANTHA AND ITS COMPOUNDS ON PLUTELLA XYLOSTELLA

Institute of Scientific and Technical Information of China (English)

Mao-xinZhang; BingLing; Shao-yingChen; Guang-wenLiang; Xiong-feiPang

2004-01-01

Repellent and oviposition deterrent activities of the essential oil from Mikania micrantha and five volatile compounds including limonene, a-terpinene, linalool, B-caryophylene and verbenone on the diamondback moth (DBM), Plutella xylostella, was investigated in door and in net-house. The results showed that the essential oil of the M. micrantha had significant repellant effect (at flow 100-180 mL/min) and oviposition deterrent activity at dose 1020 uL/seedling for the DBM. In five volatile compounds, a-terpinene, limonene and linalool had significant effect on repellent and oviposition deterrent of the DBM moths, but verbenone and B-caryophylene, no significantly effect was observed in repellent and oviposition deterrent.

Mirror-symmetry-breaking in poly[(9,9-di-n-octylfluorenyl- 2,7-diyl)-alt-biphenyl] (PF8P2) is susceptible to terpene chirality, achiral solvents, and mechanical stirring.

Science.gov (United States)

Fujiki, Michiya; Kawagoe, Yoshifumi; Nakano, Yoko; Nakao, Ayako

2013-06-17

Solvent chirality transfer of (S)-/(R)-limonenes allows the instant generation of optically active PF8P2 aggregates with distinct circular dichroism (CD)/circularly polarized luminescence (CPL) amplitudes with a high quantum yield of 16-20%. The present paper also reports subtle mirror-symmetry-breaking effects in CD-/CPL-amplitude and sign, CD/UV-vis spectral wavelengths, and photodynamics of the aggregates, though the reasons for the anomaly are unsolved. However, these photophysical properties depend on (i) the chemical natures of chiral and achiral molecules when used in solvent quantity, (ii) clockwise and counterclockwise stirring operations, and (iii) the order of addition of limonene and methanol to the chloroform solution.

Chemical constituents and insecticidal activities of the essential oil from Amomum tsaoko against two stored-product insects.

Science.gov (United States)

Wang, Ying; You, Chun-Xue; Wang, Cheng-Fang; Yang, Kai; Chen, Ran; Zhang, Wen-Juan; Du, Shu-Shan; Geng, Zhu-Feng; Deng, Zhi-Wei

2014-01-01

The aim of this research was to determine the chemical constituents and toxicities of the essential oil derived from Amomum tsaoko Crevost et Lemarie fruits against Tribolium castaneum (Herbst) and Lasioderma serricorne (Fabricius). Essential oil of A. tsaoko was obtained from hydrodistillation and was investigated by gas chromatography-mass spectrometry (GC-MS). GC-MS analysis of the essential oil resulted in the identification of 43 components, of which eucalyptol (23.87%), limonene (22.77%), 2-isopropyltoluene (6.66%) and undecane (5.74%) were the major components. With a further isolation, two active constituents were obtained from the essential oil and identified as eucalyptol and limonene. The essential oil and the two isolated compounds exhibited potential insecticidal activities against two storedproduct insects. Limonene showed pronounced contact toxicity against both insect species (LD50 = 14.97 μg/adult for T. castaneum; 13.66 μg/adult for L. serricorne) and was more toxic than eucalyptol (LD50 = 18.83 μg/adult for T. castaneum; 15.58 μg/adult for L. serricorne). The essential oil acting against the two species of insects showed LD50 values of 16.52 and 6.14 μg/adult, respectively. Eucalyptol also possessed strong fumigant toxicity against both insect species (LC50 = 5.47 mg/L air for T. castaneum; 5.18 mg/L air for L. serricorne) and was more toxic than limonene (LC50 = 6.21 mg/L air for T. castaneum; 14.07 mg/L air for L. serricorne), while the crude essential oil acting against the two species of insects showed LC50 values of 5.85 and 8.70 mg/L air, respectively. These results suggested that the essential oil of A. tsaoko and the two compounds may be used in grain storage to combat insect pests.

Air filtration media from electrospun waste high-impact polystyrene fiber membrane

Science.gov (United States)

Zulfi, Akmal; Miftahul Munir, Muhammad; Hapidin, Dian Ahmad; Rajak, Abdul; Edikresnha, Dhewa; Iskandar, Ferry; Khairurrijal, Khairurrijal

2018-03-01

Nanofiber membranes were synthesized from waste high-impact polystyrene (HIPS) using electrospinning method and then applied as air filtration media. The waste HIPS precursor solution with the concentration of 20 wt.% was prepared by dissolving waste HIPS into the mixture of d-limonene and DMF solvents. Beaded or fine nanofibers could be achieved by adjusting the ratio of solvents mixture (d-limonene and DMF). Using the ratios of solvents (d-limonene: DMF) of 3:1, 1:1, and 1:3, it was obtained beaded HIPS nanofibers with the average diameter of 272 nm, beaded HIPS nanofibers with the average diameter of 937, and fine HIPS nanofibers with the average diameter of 621 nm, respectively. From the FTIR spectral analysis, it was found that the FTIR peaks of the HIPS nanofiber membranes are the same as those of the cleaned waste HIPS and there are no FTIR peaks of DMF and d-limonene solvents. These findings implied that the electrospinning process allows the recycling of waste HIPS into HIPS nanofibers without any trapped solvent phases or apparent degradation of the original material. From the contact angle measurement, it was confirmed that the HIPS nanofiber membranes are hydrophobic and the presence of the beads in the HIPS nanofiber membranes varies their contact angles. From the air-filtration test, it was shown that the fiber morphology (beaded or fine nanofibers) considerably affects the filtration performance of the membranes. The presence of beads increased the distance between the fibers so that the pressure drop decreased. Moreover, the basis weight of the membrane greatly affected the filtration efficiency. The HIPS nanofiber membrane with the basis weight of 12.22 g m‑2 had the efficiency greater than 99.999%, which was equivalent to that of the HEPA filter.

Insecticidal activity of some citrus oils against culex quinquefasciatus

International Nuclear Information System (INIS)

Saeed, H. M. A.

2009-01-01

The present study deals with the larvicidal potency of peel oils of grapefruit (Citrus paradise), sweet orange (Citrus sinensis) and lime (Citrus aurantifolia) on 4''th instar larvae of the mosquito, Culex quinquefasciatus. Orange oil was the most effective followed by grapefruit oil and then lime oil. The toxicity of the oils applied to the 4''th instar larval stage was extended to pupal and adult stages. All oils produced deleterious effects on fecundity of survivors of sublethal doses. By the aid of chemical analysis of oils, the active compound was found to be limonene, a monoterpene compound. The percentages limonene were 97.15%, 92.46% and 32.29% for orange, grapefruit and lime respectively.(Author)

Mirror-Symmetry-Breaking in Poly[(9,9-di-n-octylfluorenyl-2,7-diyl-alt-biphenyl] (PF8P2 is Susceptible to Terpene Chirality, Achiral Solvents, and Mechanical Stirring

Directory of Open Access Journals (Sweden)

Ayako Nakao

2013-06-01

Full Text Available Solvent chirality transfer of (S-/(R-limonenes allows the instant generation of optically active PF8P2 aggregates with distinct circular dichroism (CD/circularly polarized luminescence (CPL amplitudes with a high quantum yield of 16–20%. The present paper also reports subtle mirror-symmetry-breaking effects in CD-/CPL-amplitude and sign, CD/UV-vis spectral wavelengths, and photodynamics of the aggregates, though the reasons for the anomaly are unsolved. However, these photophysical properties depend on (i the chemical natures of chiral and achiral molecules when used in solvent quantity, (ii clockwise and counterclockwise stirring operations, and (iii the order of addition of limonene and methanol to the chloroform solution.

Terbinafine hydrochloride nanovesicular gel: In vitro characterization, ex vivo permeation and clinical investigation.

Science.gov (United States)

AbdelSamie, Sara M; Kamel, Amany O; Sammour, Omaima A; Ibrahim, Shady M

2016-06-10

In this work, nanovesicular chitosan gels were prepared for dermal delivery of terbinafine hydrochloride (TBN HCl). Ethosomes and vesicles containing different types of penetration enhancers (PEs) viz. Terpenes (cineole and limonene), labrasol and transcutol were developed. The prepared vesicles were evaluated for physical characteristics as well as skin interaction. The selected vesicles were incorporated into chitosan gel. An in vivo animal study was done on rat induced superficial Candida infection model. Moreover, randomized double blind clinical study was done on patients to compare the effect of the selected nanovesicular gel against the market product. Results showed the formation of nearly spherical, mostly deformable vesicular systems with size range of 95.5-530nm, zeta potential range of -0.1 to 15mV and entrapment efficiency range of 20-96.7%. Penetration enhancer vesicles (PEVs) prepared with 4% limonene (ELI4) showed the highest percent of drug deposition in the skin (53%) and the highest local accumulation efficiency value (35.3). In vivo animal study showed that the lowest fungal burden produced with ELI4 chitosan gel. Clinical studies showed cure rate of 86% within 7days treatment in case of limonene nanovesicular gel compared to 20% for market product (Lamisil® cream). Copyright © 2016 Elsevier B.V. All rights reserved.

Antifungal Activity of Thapsia villosa Essential Oil against Candida, Cryptococcus, Malassezia, Aspergillus and Dermatophyte Species

Directory of Open Access Journals (Sweden)

Eugénia Pinto

2017-09-01

Full Text Available The composition of the essential oil (EO of Thapsia villosa (Apiaceae, isolated by hydrodistillation from the plant’s aerial parts, was analysed by GC and GC-MS. Antifungal activity of the EO and its main components, limonene (57.5% and methyleugenol (35.9%, were evaluated against clinically relevant yeasts (Candida spp., Cryptococcus neoformans and Malassezia furfur and moulds (Aspergillus spp. and dermatophytes. Minimum inhibitory concentrations (MICs were measured according to the broth macrodilution protocols by Clinical and Laboratory Standards Institute (CLSI. The EO, limonene and methyleugenol displayed low MIC and MFC (minimum fungicidal concentration values against Candida spp., Cryptococcus neoformans, dermatophytes, and Aspergillus spp. Regarding Candida species, an inhibition of yeast–mycelium transition was demonstrated at sub-inhibitory concentrations of the EO (MIC/128; 0.01 μL/mL and their major compounds in Candida albicans. Fluconazole does not show this activity, and the combination with low concentrations of EO could associate a supplementary target for the antifungal activity. The association of fluconazole with T. villosa oil does not show antagonism, but the combination limonene/fluconazole displays synergism. The fungistatic and fungicidal activities revealed by T. villosa EO and its main compounds, associated with their low haemolytic activity, confirm their potential antimicrobial interest against fungal species often associated with human mycoses.

Succinic acid production from orange peel and wheat straw by batch fermentations of Fibrobacter succinogenes S85.

Science.gov (United States)

Li, Qiang; Siles, Jose A; Thompson, Ian P

2010-10-01

Succinic acid is a platform molecule that has recently generated considerable interests. Production of succinate from waste orange peel and wheat straw by consolidated bioprocessing that combines cellulose hydrolysis and sugar fermentation, using a cellulolytic bacterium, Fibrobacter succinogenes S85, was studied. Orange peel contains D-limonene, which is a well-known antibacterial agent. Its effects on batch cultures of F. succinogenes S85 were examined. The minimal concentrations of limonene found to inhibit succinate and acetate generation and bacterial growth were 0.01%, 0.1%, and 0.06% (v/v), respectively. Both pre-treated orange peel by steam distillation to remove D: -limonene and intact wheat straw were used as feedstocks. Increasing the substrate concentrations of both feedstocks, from 5 to 60 g/L, elevated succinate concentration and productivity but lowered the yield. In addition, pre-treated orange peel generated greater succinate productivities than wheat straw but had similar resultant titres. The greatest succinate titres were 1.9 and 2.0 g/L for pre-treated orange peel and wheat straw, respectively. This work demonstrated that agricultural waste such as wheat straw and orange peel can be biotransformed to succinic acid by a one-step consolidated bioprocessing. Measures to increase fermentation efficiency are also discussed.

Fancy citrus, feel good: Positive judgment of citrus odor, but not the odor itself, is associated with elevated mood during experienced helplessness

Directory of Open Access Journals (Sweden)

Matthias eHoenen

2016-02-01

Full Text Available Aromatherapy claims that citrus essential oils exert mood lifting effects. Controlled studies, however, have yielded inconsistent results. Notably, studies so far did not control for odor pleasantness, although pleasantness is a critical determinant of emotional responses to odors. This study investigates mood lifting effects of d-(+-limonene, the most prominent substance in citrus essential oils, with respect to odor quality judgments.Negative mood was induced within 78 participants using a helplessness paradigm (unsolvable social discrimination task. During this task, participants were continuously (mean duration: 19.5 min exposed to d-(+-limonene (n = 25, vanillin (n = 26, or diethyl phthalate (n = 27. Participants described their mood (Self-Assessment-Manikin, basic emotion ratings and judged the odors’ quality (intensity, pleasantness, unpleasantness, familiarity prior to and following the helplessness induction. The participants were in a less positive mood after the helplessness induction (p < .001, irrespective of the odor condition. Still, the more pleasant the participants judged the odors, the less effective the helplessness induction was in reducing happiness (p = .019.The results show no odor specific mood lifting effect of d-(+-limonene, but indicate a positive effect of odor pleasantness on mood. The study highlights the necessity to evaluate odor judgments in aromatherapy research.

Supporting Families to Support Students

Science.gov (United States)

Kelly, John; Rossen, Eric; Cowan, Katherine C.

2018-01-01

Collaboration between students' families and the school is an essential component to promoting student mental and behavioral health. Many schools structure their mental health services using a Multi-Tiered System of Supports that offers three different tiers of support from universal supports to personalized help for students with serious…

Effect of bio-fertilizers and gamma radiation on the essential oil of dill at the vegetative, flowering, fruiting stages and their antimicrobial activities

International Nuclear Information System (INIS)

Said -Al Ahl, Hussein A.H.; Abou -Zeid, El-Shahat N.; Ali, Mohamed S.; Naguib, Nabila Y.; Sarhan, Atef M.; Abou Dahab, Abou Dahab M.; El-Bendary, Magda A.

2014-01-01

This study was carried out to investigate the response of dill plants to gamma radiation and bio- fertilizers on the essential oils and their constituents during vegetative, flowering and fruiting stages. The results showed that the most effective treatment on the volatile oil content in the three stages was 2 k -rad + bio- fertilizers. The major compounds were found to be α -phellandrene, limonene, β -phellandrene and p- cymene (vegetative stage). In the flowering stage, p- cymene, carvone, dillether and dillapiole. Whereas, carvone, dillapiole and limonene were major compounds (fruiting stage). The results showed those dill volatile oils at different developing stages exhibited strong and a variable degree of antimicrobial activity. Key words: dill (Anethum graveoleus L.) essential oil, gamma radiation, biofertilizer, anti -microbial

Development and implementation of the IPCS conceptual framework for evaluating mode of action of chemical carcinogens

International Nuclear Information System (INIS)

Dybing, E.

2002-01-01

The framework developed by the International Programme on Chemical Safety (IPCS) for assessing the mode of action of tumour induction of chemicals in experimental animals has been illustrated with d-limonene, sodium saccharin, di(2-ethylhexyl)phthalate (DEHP) and sulfamethazine as examples. d-Limonene causes renal tumours only in male rats through a response associated with α 2u -globulin. Sodium saccharin induces urinary bladder tumours only in male rats through formation of a urinary precipitate causing erosion of the bladder surface and extensive regenerative hyperplasia. DEHP causes liver tumours in rats and mice through activation of the receptor PPARα leading to peroxisome proliferation and hepatocellular proliferation. Sulfamethazine induces thyroid follicular cell tumours in rats and mice through a mechanism involving altered thyroid hormone homeostasis

Study of the solubility and stability of polystyrene wastes in a dissolution recycling process

International Nuclear Information System (INIS)

Garcia, Maria Teresa; Gracia, Ignacio; Duque, Gema; Lucas, Antonio de; Rodriguez, Juan Francisco

2009-01-01

Dissolution with suitable solvents is one of the cheapest and more efficient processes for polystyrene waste management. In this work the solubility of polystyrene foams in several solvents benzene, toluene, xylene, tetrahydrofuran, chloroform, 1,3-butanediol, 2-butanol, linalool, geraniol, d-limonene, p-cymene, terpinene, phellandrene, terpineol, menthol, eucalyptol, cinnamaldheyde, nitrobenzene, N,N-dimethylformamide and water has been determined. Experimental results have shown that to develop a 'green process' the constituents of essential oils, d-limonene, p-cymene, terpinene, phellandrene, are the most appropriate solvents. The action of these solvent does not produce any degradation of polymer chains. The solubility of the polymer in the mentioned solvents at different temperatures has been investigated. The solvent can be easily recycled by distillation.

A support shield for a powered support

Energy Technology Data Exchange (ETDEWEB)

Korczynski, P; Rojicek, P

1982-08-31

The subject of this invention is a support shield for a powered support. This shield resists creep of the coal from the longwall face, including an inclined longwall. It involves an arrangement wherein the distributor hinge is separated into upper and lower sections. The lower section holds a second hinge and the end of the rod of the pressure cylinder, one end of which is connected to the roof support. An advantage of the support is that compared to existing supports, it is self-advancing and holds stopes with coal which slopes in its formation or has inrushes. To a certain degree it prevents the stope space from ejecting fine pieces of rock from the longwall roof using an inter-timber support between the powered support and the stope. The support shield is moved by a simple system of levers which makes it possible, using a pressurized cylinder, to transmit a significant force to the coal stope. In this case, when the coal inrushes exceed the designed capabilities of the shield, a wooden extension piece is placed between the support and the face, through which the support pressure is applied.

Potentiometric and spectrophotometric titration study of interaction of tungstovanadophosphoric heteropolyacids with sodium hydroxide

International Nuclear Information System (INIS)

Borkoyakov, S.A.; Fisun, L.A.

1988-01-01

The methods of potentiometric and spectrophotometric titration are used to study H s+n PW 12-n V n O 40 (n=1,2) (P-W-V HPA) decomposition by sodium hydroxide. It is shown that at the first stage of heteropolyanion interaction with alkali (pH) > 4 P-W-V HPA structural reconstruction takes place. It is accompanied by the formation of complexes with a higher content of vanadium atoms stable at pH 4-7/ P-W-V HPA decomposition to initial salts occurs at pH > 8

Use of heteroligand complexes in analytical chemistry of niobium and tantalum

International Nuclear Information System (INIS)

Elinson, S.V.

1975-01-01

A review of modern precise spectrophotometric and extraction-spectrophotometric methods for analyzing Nb and Ta is presented. These methods are based on the use of multi-ligand (trinary, quaternary, mixed) complexes of these elements with organic reagents. To develop extraction-photometric methods for quantitative analysis of Ta in the presence of Nb use is made of complexes which these elements form with polyphenols, azo compounds, metallochromic indicators and heteropolyacids. The extraction-photometric methods are based on the use of multi-ligand complexes of the ionic association type. Owing to this the volumetric and gravimetric methods can be used here. The research on multi-ligand complexes of Nb and Ta with a number of reagents provides a basis for developing precise analytical methods for determining Nb and Ta in different materials and in the presence of many other elements without their separation

Dynamic potential and surface morphology study of sertraline membrane sensors

Science.gov (United States)

Khater, M.M.; Issa, Y.M.; Hassib, H.B.; Mohammed, S.H.

2014-01-01

New rapid, sensitive and simple electrometric method was developed to determine sertraline hydrochloride (Ser-Cl) in its pure raw material and pharmaceutical formulations. Membrane sensors based on heteropolyacids as ion associating material were prepared. Silicomolybdic acid (SMA), silicotungstic acid (STA) and phosphomolybdic acid (PMA) were used. The slope and limit of detection are 50.00, 60.00 and 53.24 mV/decade and 2.51, 5.62 and 4.85 μmol L−1 for Ser-ST, Ser-PM and Ser-SM membrane sensors, respectively. Linear range is 0.01–10.00 for the three sensors. These new sensors were used for the potentiometric titration of Ser-Cl using sodium tetraphenylborate as titrant. The surface morphologies of the prepared membranes with and without the modifier (ion-associate) were studied using scanning and atomic force microscopes. PMID:26257944

The analysis of impurities in the diuranate-determination of phosphate by phosphomolybdate blue spectrophotometric method

International Nuclear Information System (INIS)

Sun Haobo

2014-01-01

Phosphomolybdenum blue spectrophotometric method was used for determination of phosphate in the diuranate. Diuranate was dissolved in nitric acid solution, in which formed a soluble heteropolyacid complex (namely phosphomolybdenum yellow) due to interaction of phosphate and ammonium molybdate. Then phosphomolybdenum yellow was reduced to phosphomolybdenum blue with Bismuth nitrate as catalyst. Colour intensity at 700 nm is in proportion to the content of phosphate determined by spectrophotometric method. This experiment presents good linearity at the range of 30 μg to 245 μg phosphate, and the relative standard deviation of the experimental result is 2.4%, and the recovery rate is from 95% to 105%. The determination result of phosphate content will not be effected under conditions of 4 mg of SiO 2 , 6 mg of Fe, 400 mg of Cl - and 4.5 mg of Ge in the solution. (author)

Determination of equilibrium constants of formation and decomposition of 11-tungstophosphate heteropolyanion by the method of Raman spectroscopy

International Nuclear Information System (INIS)

Detusheva, L.G.; Khankhasaeva, S.Ts.; Yurchenko, Eh.N.; Lazarenko, T.P.; Kozhevnikov, I.V.

1990-01-01

Method of quantitative IR spectroscopy was used to determine equilibrium constants of formation of H x PW 11 O 39 (7-x)- (1) from H y P 2 W 21 O 71 (6-Y)- and W 10 O 32 4- at pH 2.8-4.0 and its decomposition at pH 7-8. Equilibrium constant of (1) formation in logarithmic coordinates changes linearly with growth of initial concentration of H 3 PW 12 O 40 (2) from 0.005 to 0.1 mol/l. Equilibrium constant of (1) decomposition is characterized by complex dependence on initial concentration of (2) due to proceeding of parallel reactions. Equilibrium concentrations of compounds in solutions of tungstophosphoric heteropolyacid at pH 3.25 and 7.68, calculated according to determined equilibrium constants and determined by the method of NMR on 31 P nuclei, were correlated

Heterogeneous conversion of NO2 on secondary organic aerosol surfaces: A possible source of nitrous acid (HONO in the atmosphere?

Directory of Open Access Journals (Sweden)

R. Bröske

2003-01-01

Full Text Available The heterogeneous conversion of NO2 on different secondary organic aerosols (SOA was investigated with the focus on a possible formation of nitrous acid (HONO. In one set of experiments different organic aerosols were produced in the reactions of O3 with alpha-pinene, limonene or catechol and OH radicals with toluene or limonene, respectively. The aerosols were sampled on filters and exposed to humidified NO2  mixtures under atmospheric conditions. The estimated upper limits for the uptake coefficients of NO2  and the reactive uptake coefficients NO2  -> HONO are in the range of 10-6 and 10-7, respectively. The integrated HONO formation for 1 h reaction time was 13 cm-2 geometrical surface and 17 g-1 particle mass. In a second set of experiments the conversion of NO2 into HONO in the presence of organic particles was carried out in an aerosol flow tube under atmospheric conditions. In this case the aerosols were produced in the reaction of O3 with beta-pinene, limonene or catechol, respectively. The upper limits for the reactive uptake coefficients NO2 -> HONO were in the range of 7 x 10-7 - 9 x 10-6. The results from the present study show that heterogeneous formation of nitrous acid on secondary organic aerosols (SOA is unimportant for the atmosphere.

Rhodotorula bloemfonteinensis sp. nov., Rhodotorula eucalyptica sp. nov., Rhodotorula orientis sp. nov. and Rhodotorula pini sp. nov., yeasts isolated from monoterpene-rich environments.

Science.gov (United States)

Pohl, Carolina H; Smit, Martha S; Albertyn, Jacobus

2011-09-01

Recent rDNA sequencing of 25 isolates from a previous study, during which limonene-utilizing yeasts were isolated from monoterpene-rich environments by using 1,4-disubstituted cyclohexanes as sole carbon sources, led to the identification of four hitherto unknown Rhodotorula species. Analyses of the 26S rDNA D1/D2 region as well as the internal transcribed spacer (ITS) domain indicated that two isolates (CBS 8499(T) and CBS 10736) were identical and were closely related to Rhodotorula cycloclastica, a previously described limonene-utilizing yeast. These novel isolates differed from known yeast species and could be distinguished from R. cycloclastica by standard physiological tests. The other three isolates represent three novel Rhodotorula species, closely related to Sporobolomyces magnisporus. These three species could also be distinguished from other Rhodotorula species by standard physiological tests. Based on these results, we suggest that the new isolates represent novel species, for which the names Rhodotorula eucalyptica sp. nov. (type strain CBS 8499(T)  = NRRL Y-48408(T)), Rhodotorula pini sp. nov. (type strain CBS 10735(T)  = NRRL Y-48410(T)), Rhodotorula bloemfonteinensis sp. nov. (type strain CBS 8598(T)  = NRRL Y-48407(T)) and Rhodotorula orientis sp. nov. (type strain CBS 8594(T)  = NRRL Y-48719(T)) are proposed. R. eucalyptica and R. pini can also utilize limonene.

Contact and Repellent Activities of the Essential Oil from Juniperus formosana against Two Stored Product Insects

Directory of Open Access Journals (Sweden)

Shanshan Guo

2016-04-01

Full Text Available The chemical composition of the essential oil from Juniperus formosana leaves and its contact and repellent activities against Tribolium castaneum and Liposcelis bostrychophila adults were investigated. The essential oil of J. formosana leaves was obtained by hydrodistillation and analyzed by GC-MS. A total of 28 components were identified and the main compounds in the essential oil were α-pinene (21.66%, 4-terpineol (11.25%, limonene (11.00% and β-phellandrene (6.63%. The constituents α-pinene, 4-terpineol and d-limonene were isolated from the essential oil. It was found that the essential oil exhibited contact activity against T. castaneum and L. bostrychophila adults (LD50 = 29.14 μg/adult and 81.50 µg/cm2, respectively. The compound 4-terpineol exhibited the strongest contact activity (LD50 = 7.65 μg/adult. In addition, data showed that at 78.63 nL/cm2, the essential oil and the three isolated compounds strongly repelled T. castaneum adults. The compounds α-pinene and d-limonene reached the same level (Class V of repellency as DEET (p = 0.396 and 0.664 against L. bostrychophila at 63.17 nL/cm2 after 2 h treatment. The results indicate that the essential oil and the isolated compounds have potential to be developed into natural insecticides and repellents to control insects in stored products.

Characterization of the Migration of Hop Volatiles into Different Crown Cork Liner Polymers and Can Coatings.

Science.gov (United States)

Wietstock, Philip C; Glattfelder, Richard; Garbe, Leif-Alexander; Methner, Frank-Jürgen

2016-04-06

Absorption of hop volatiles by crown cork liner polymers and can coatings was investigated in beer during storage. All hop volatiles measured were prone to migrate into the closures, and the absorption kinetics was demonstrated to fit Fick's second law of diffusion well for a plane sheet. The extent and rate of diffusion were significantly dissimilar and were greatly dependent upon the nature of the volatile. Diffusion coefficients ranged from 1.32 × 10(-5) cm(2)/day (limonene) to 0.26 × 10(-5) cm(2)/day (α-humulene). The maximum amounts absorbed into the material at equilibrium were in the following order: limonene > α-humulene > trans-caryophyllene > myrcene ≫ linalool > α-terpineol > geraniol. With the application of low-density polyethylene (LDPE) liners with oxygen-scavenging functionality, oxygen-barrier liners made up from high-density polyethylene (HDPE) or liner polymers from a different manufacturer had no significant effect on the composition of hop volatiles in beers after prolonged storage of 55 days; however, significantly higher amounts of myrcene and limonene were found in the oxygen-barrier-type crown cork, while all other closures behaved similarly. Can coatings were demonstrated to absorb hop volatiles in a similar pattern as crown corks but to a lesser extent. Consequently, significantly higher percentages of myrcene were found in the beers.

The essential oil from the flowers of Citrus maxima (J. Burman) Merrill from Vietnam

NARCIS (Netherlands)

Dung, N.X.; Pha, Nguyen M.; Lo, Vu N.; An, N.T.K.; Leclercq, P.A.

1991-01-01

Thirty-five compounds have been identified in the flower oil of Citrus maxima (J. Burman) Merrill. The major components were limonene (18.2%), linalool (16.4%), nerolidol (29.3%) and farnesol (15.7%).

Discovery and characterization of thermophilic limonene-1,2-epoxide hydrolases from hot spring metagenomic libraries

DEFF Research Database (Denmark)

Ferrandi, Erica Elisa; Sayer, Christopher; Isupov, Michail N.

2015-01-01

thermophilic sources, have higher optimal temperatures and apparent melting temperatures than Re-LEH. The new LEH enzymes have been crystallized and their structures solved to high resolution in the native form and in complex with the inhibitor valpromide for Tomsk-LEH and poly(ethylene glycol) for CH55-LEH......,2-epoxide hydrolase (LEH) family of enzymes. These two LEHs (Tomsk-LEH and CH55-LEH) show EH activities towards different epoxide substrates, differing in most cases from those previously identified for Rhodococcus erythropolis (Re-LEH) in terms of stereoselectivity. Tomsk-LEH and CH55-LEH, both from....... The structural analysis has provided insights into the LEH mechanism, substrate specificity and stereoselectivity of these new LEH enzymes, which has been supported by mutagenesis studies....

Environ: E00434 [KEGG MEDICUS

Lifescience Database Archive (English)

Full Text Available E00434 Anethum graveolens fruit Anethi fructus Crude drug Carvone [CPD:C01767 C113...83], Limonene [CPD:C06078] Anethum graveolens [TAX:40922] ... Apiaceae (carrot family) Anethum graveolens fruit (dried) ...

Effect of xanthan gum on the release of strawberry flavor in formulated soy beverage.

Science.gov (United States)

Xu, Jiao; He, Zhiyong; Zeng, Maomao; Li, Bingbing; Qin, Fang; Wang, Linxiang; Wu, Shengfang; Chen, Jie

2017-08-01

The effects of xanthan gum on the release of strawberry flavor compounds in formulated soy protein isolate (SPI) beverage were investigated by headspace gas chromatography (GC). Seven strawberry flavor compounds (limonene, ethyl hexanoate, (Z)-3-hexenyl acetate, ethyl 2-methylbutanoate, ethyl butanoate, (Z)-3-hexen-1-ol and diacetyl) could be detected by GC and hence analyzed the gas-matrix partition coefficients (K). The release of flavor compounds was restrained in SPI and/or xanthan gum solution. The retention of (Z)-3-hexen-1-ol, limonene and diacetyl significantly changed (pfuraneol) accelerated the release of ester compounds to some extent in different matrices. The above results demonstrated that presence of SPI and xanthan gum could bring about an imbalance in the strawberry flavor. Copyright © 2017 Elsevier Ltd. All rights reserved.

Determination of volatile compounds by gas liquid chromatography in tropical fruit, guava (psidium guajav L.)

International Nuclear Information System (INIS)

Hussain, A.; Zeb-un-Nisa; Asi, M. R.; Ahmad, R.; Iqbal, Z.; Maqbool, A. B.

2002-01-01

Volatile flavor components from both white and pink guava fruits were collected using Likens-Nickerson concurrent Distillation Extraction method and were analyzed by GC/FID. In the essence collected by using likens-Nickerson concurrent distillation extraction apparatus, 23 compounds were present in white guava fruit, of which 11 compounds (furfural, alpha-pinene, trans-2-hexene-1-ol, 2-heptanone, benzaldehyde, hexyl acetate Beta-ionone, limonene, 2-nonanone, cinamyl acetate and octyl acetate) were identified. Similarly for pink guava fruit, 13 compounds out of 29 compounds were identified by comparing retention times of unknown with that of standard compounds and sniffing at the odour port. These were hexanal, furfural, 2-heptanone, benzaldehyde, methyl furfural hexyl acetate, beta-ionone, alpha-pinene, 2-nonanone, limonene, cinnamyl acetate, ethyl undecanoate and octyl acetate. (author)

Gas chromatography-mass spectrometry study of the essential oils of Schinus longifolia (Lindl.) speg., Schinus fasciculata (Griseb.) I. M. Johnst., and Schinus areira L.

Science.gov (United States)

Murray, Ana P; Frontera, María A; Tomas, María A; Mulet, María C

2005-01-01

The essential oil composition from the aerial parts of three Anacardiaceae growing in Bahía Blanca, Argentina was studied by gas chromatography and gas chromatography-mass spectrometry. The essential oils of S. longifolia and S. fasciculata have been studied for the first time. The major constituents were alpha-pinene (46.5%), beta-pinene (15.1%) and alpha-phellandrene (10.1%) for S. longifolia and limonene (10.9%), beta-phellandrene (6.16%) and alpha-phellandrene (5.6%) for S. fasciculata. The major components of the essential oil of S. areira were limonene (28.6%), alpha-phellandrene (10.1%), sabinene (9.2%) and camphene (9.2%) differing from the literature data. The essential oils from S. areira and S. longifolia exhibited a high biotoxicity in a brine shrimp assay with Artemia persimilis.

Prenatal family support, postnatal family support and postpartum depression.

Science.gov (United States)

Xie, Ri-Hua; Yang, Jianzhou; Liao, Shunping; Xie, Haiyan; Walker, Mark; Wen, Shi Wu

2010-08-01

Inadequate social support is an important determinant of postpartum depression (PPD). Social support for pregnant women consists of supports from various sources and can be measured at different gestation periods. Differentiating the effects of social support from different sources and measured at different gestation periods may have important implications in the prevention of PPD. In the family centred Chinese culture, family support is likely to be one of the most important components in social support. The aim of this study was to assess the association of prenatal family support and postnatal family support with PPD. A prospective cohort study was conducted between February and September 2007 in Hunan, China. Family support was measured with social support rating scale at 30-32 weeks of gestation (prenatal support) and again at 2 weeks of postpartum visit (postnatal support). PPD was defined as Edinburgh Postnatal Depression Scale (EPDS) score > or =13. A total of 534 pregnant women were included, and among them, 103 (19.3%) scored 13 or more on the EPDS. PPD was 19.4% in the lowest tertile versus 18.4% in the highest quartile (adjusted odds ratio: 1.04, 95% confidence interval 0.60, 1.80) for prenatal support from all family members, and PPD was 39.8% in the lowest tertile versus 9.6% in the highest tertile (adjusted odds ratio: 4.4, 95% confidence interval 2.3, 8.4) for postnatal support from all family members. Among family members, support from husband had the largest impact on the risk of developing PPD. Lack of postnatal family support, especially the support from husband, is an important risk factor of PPD.

Isolation of volatile compounds of Aloe excelsa (Berger ...

African Journals Online (AJOL)

PROMOTING ACCESS TO AFRICAN RESEARCH ... Industrial and pharmacological applications of volatile and non-volatile compounds isolated ... Three commercially important compounds, namely: phenylacetonitrile, carvone and limonene were identified using gas ... EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

Examining the Support Peer Supporters Provide Using Structural Equation Modeling: Nondirective and Directive Support in Diabetes Management.

Science.gov (United States)

Kowitt, Sarah D; Ayala, Guadalupe X; Cherrington, Andrea L; Horton, Lucy A; Safford, Monika M; Soto, Sandra; Tang, Tricia S; Fisher, Edwin B

2017-12-01

Little research has examined the characteristics of peer support. Pertinent to such examination may be characteristics such as the distinction between nondirective support (accepting recipients' feelings and cooperative with their plans) and directive (prescribing "correct" choices and feelings). In a peer support program for individuals with diabetes, this study examined (a) whether the distinction between nondirective and directive support was reflected in participants' ratings of support provided by peer supporters and (b) how nondirective and directive support were related to depressive symptoms, diabetes distress, and Hemoglobin A1c (HbA1c). Three hundred fourteen participants with type 2 diabetes provided data on depressive symptoms, diabetes distress, and HbA1c before and after a diabetes management intervention delivered by peer supporters. At post-intervention, participants reported how the support provided by peer supporters was nondirective or directive. Confirmatory factor analysis (CFA), correlation analyses, and structural equation modeling examined the relationships among reports of nondirective and directive support, depressive symptoms, diabetes distress, and measured HbA1c. CFA confirmed the factor structure distinguishing between nondirective and directive support in participants' reports of support delivered by peer supporters. Controlling for demographic factors, baseline clinical values, and site, structural equation models indicated that at post-intervention, participants' reports of nondirective support were significantly associated with lower, while reports of directive support were significantly associated with greater depressive symptoms, altogether (with control variables) accounting for 51% of the variance in depressive symptoms. Peer supporters' nondirective support was associated with lower, but directive support was associated with greater depressive symptoms.

In situ measurements of isoprene and monoterpenes within a south-east Asian tropical rainforest

Directory of Open Access Journals (Sweden)

C. E. Jones

2011-07-01

Full Text Available Biogenic volatile organic compounds (BVOCs emitted from tropical rainforests comprise a substantial fraction of global atmospheric VOC emissions, however there are only relatively limited measurements of these species in tropical rainforest regions. We present observations of isoprene, α-pinene, camphene, Δ-3-carene, γ-terpinene and limonene, as well as oxygenated VOCs (OVOCs of biogenic origin such as methacrolein, in ambient air above a tropical rainforest in Malaysian Borneo during the Oxidant and Particle Photochemical Processes above a south-east Asian tropical rainforest (OP3 project in 2008. Daytime composition was dominated by isoprene, with an average mixing ratio of the order of ~1 ppb. γ-terpinene, limonene and camphene were the most abundant monoterpenes, with average daytime mixing ratios of 102, 71 and 66 ppt respectively, and with an average monoterpene toisoprene ratio of 0.3 during sunlit hours, compared to 2.0 at night. Limonene and camphene abundances were seen to be related to both temperature and light conditions. In contrast, γ-terpinene emission continued into the late afternoon/evening, under relatively low temperature and light conditions. The contributions of isoprene, monoterpenes and other classes of VOC to the volatile carbon budget and OH reactivity have been summarised for this rainforest location. We observe good agreement between surface and aircraft measurements of boundary layer isoprene and methacrolein above the natural rainforest, suggesting that the ground-level observations are broadly representative of isoprene emissions from this region.

Anti-Inflammatory Properties and Chemical Characterization of the Essential Oils of Four Citrus Species.

Science.gov (United States)

Amorim, Jorge Luis; Simas, Daniel Luiz Reis; Pinheiro, Mariana Martins Gomes; Moreno, Daniela Sales Alviano; Alviano, Celuta Sales; da Silva, Antonio Jorge Ribeiro; Fernandes, Patricia Dias

2016-01-01

Citrus fruits have potential health-promoting properties and their essential oils have long been used in several applications. Due to biological effects described to some citrus species in this study our objectives were to analyze and compare the phytochemical composition and evaluate the anti-inflammatory effect of essential oils (EO) obtained from four different Citrus species. Mice were treated with EO obtained from C. limon, C. latifolia, C. aurantifolia or C. limonia (10 to 100 mg/kg, p.o.) and their anti-inflammatory effects were evaluated in chemical induced inflammation (formalin-induced licking response) and carrageenan-induced inflammation in the subcutaneous air pouch model. A possible antinociceptive effect was evaluated in the hot plate model. Phytochemical analyses indicated the presence of geranial, limonene, γ-terpinene and others. EOs from C. limon, C. aurantifolia and C. limonia exhibited anti-inflammatory effects by reducing cell migration, cytokine production and protein extravasation induced by carrageenan. These effects were also obtained with similar amounts of pure limonene. It was also observed that C. aurantifolia induced myelotoxicity in mice. Anti-inflammatory effect of C. limon and C. limonia is probably due to their large quantities of limonene, while the myelotoxicity observed with C. aurantifolia is most likely due to the high concentration of citral. Our results indicate that these EOs from C. limon, C. aurantifolia and C. limonia have a significant anti-inflammatory effect; however, care should be taken with C. aurantifolia.

Anti-Inflammatory Properties and Chemical Characterization of the Essential Oils of Four Citrus Species.

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Jorge Luis Amorim

Full Text Available Citrus fruits have potential health-promoting properties and their essential oils have long been used in several applications. Due to biological effects described to some citrus species in this study our objectives were to analyze and compare the phytochemical composition and evaluate the anti-inflammatory effect of essential oils (EO obtained from four different Citrus species. Mice were treated with EO obtained from C. limon, C. latifolia, C. aurantifolia or C. limonia (10 to 100 mg/kg, p.o. and their anti-inflammatory effects were evaluated in chemical induced inflammation (formalin-induced licking response and carrageenan-induced inflammation in the subcutaneous air pouch model. A possible antinociceptive effect was evaluated in the hot plate model. Phytochemical analyses indicated the presence of geranial, limonene, γ-terpinene and others. EOs from C. limon, C. aurantifolia and C. limonia exhibited anti-inflammatory effects by reducing cell migration, cytokine production and protein extravasation induced by carrageenan. These effects were also obtained with similar amounts of pure limonene. It was also observed that C. aurantifolia induced myelotoxicity in mice. Anti-inflammatory effect of C. limon and C. limonia is probably due to their large quantities of limonene, while the myelotoxicity observed with C. aurantifolia is most likely due to the high concentration of citral. Our results indicate that these EOs from C. limon, C. aurantifolia and C. limonia have a significant anti-inflammatory effect; however, care should be taken with C. aurantifolia.

Antimicrobial activity of berries and leaves essential oils of Macedonian Juniperus foetidissima Willd. (Cupressaceae

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Floresha Sela

2015-04-01

Full Text Available Chemical composition and antimicrobial activity of leaves and berries essential oils from Juniperus foetidissima Willd. (Cupressaceae grown in R. Macedonia (RM was investigated. GC/FID/MS analysis was carried out and 93 components were identified, representing 89.7-96.5% of the oils. The major components of the berries essential oil were α-pinene (19.2%, limonene (24.9% and cedrol (23.1%, followed by smaller amounts of b-funebrene, trans-caryophyllene, germacrene D and d-cadinene. The composition of the leaves essential oil was variable depending on the region of collection. Accordingly, samples originated from southeastern RM contained essential oil with α-pinene (67.6% and limonene (10.0%, from central part of RM with limonene (17.9-27.1% and cedrol (28.8-33.9%, while samples from southwestern RM contained oil with terpinen-4-ol (19.1%, cis-thujone (8.3%, germacrene D (11.0% and d-cadinene (6.3% as predominant components in the oil. Antimicrobial screening of the essential oils was made by disc diffusion and broth dilution method against 16 bacterial strains of Gram-positive and Gram-negative bacteria and one strain of Candida albicans. The leaves essential oil showed stronger antimicrobial activity against Staphylococcus aureus, Streptococcus pyogenes and Haemophilus influenzae (MIC = 125 ml/ml and moderate activity against Campylobacter jejuni (MIC > 500 ml/ml. Other investigated bacterial strains and Candida albicans were completely resistant to the antimicrobial activity of J. foetidissima essential oils.

Volatile organic compound conversion by ozone, hydroxyl radicals, and nitrate radicals in residential indoor air: Magnitudes and impacts of oxidant sources

Science.gov (United States)

Waring, Michael S.; Wells, J. Raymond

2015-04-01

Indoor chemistry may be initiated by reactions of ozone (O3), the hydroxyl radical (OH), or the nitrate radical (NO3) with volatile organic compounds (VOC). The principal indoor source of O3 is air exchange, while OH and NO3 formation are considered as primarily from O3 reactions with alkenes and nitrogen dioxide (NO2), respectively. Herein, we used time-averaged models for residences to predict O3, OH, and NO3 concentrations and their impacts on conversion of typical residential VOC profiles, within a Monte Carlo framework that varied inputs probabilistically. We accounted for established oxidant sources, as well as explored the importance of two newly realized indoor sources: (i) the photolysis of nitrous acid (HONO) indoors to generate OH and (ii) the reaction of stabilized Criegee intermediates (SCI) with NO2 to generate NO3. We found total VOC conversion to be dominated by reactions both with O3, which almost solely reacted with D-limonene, and also with OH, which reacted with D-limonene, other terpenes, alcohols, aldehydes, and aromatics. VOC oxidation rates increased with air exchange, outdoor O3, NO2 and D-limonene sources, and indoor photolysis rates; and they decreased with O3 deposition and nitric oxide (NO) sources. Photolysis was a strong OH formation mechanism for high NO, NO2, and HONO settings, but SCI/NO2 reactions weakly generated NO3 except for only a few cases.

HS-SPME AS AN EFFICIENT TOOL FOR DISCRIMINATING CHEMOTYPES OF Lippia alba (Mill. N. E. Brown

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Aiêrta C. C. da Silva

Full Text Available Lippia alba (Mill. N. E. Brown (Verbenaceae is a medicinal plant for which several biological activities are reported, such as sedative, anxiolytic, anti-ulcer, antifungal, antimicrobial, antioxidant, antispasmodic, anti-nociceptive and anti-inflammatory. It is characterized by the production of essential oils which have been used to classify the plant in different chemotypes. In the Northeast region of Brazil, the presence of three chemotypes are reported: myrcene-citral (chemotype I, limonene-citral (chemotype II and carvone-limonene (chemotype III. In this work, headspace-solid phase microextraction (HS-SPME was used on the analysis of the volatile organic compounds (VOCs of three chemotypes of L. alba from the Northeast region of Brazil, and compared to the essential oils of the plants extracted by hydrodistillation. Volatile compounds from each chemotype were more effectively differentiated when extracted by HS-SPME than by hydrodistillation.

Differences in volatile composition and sexual morphs in rambutan (Nephelium lappaceum L. flowers and their effect in the Apis mellifera L. (Hymenoptera, Apidae attraction

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Lorena Aceves-Chong

Full Text Available ABSTRACT We studied the volatile composition and sexual morphs of Nephelium lappaceum flowers from two orchards, and investigated the choice behavior of the honey bee, Apis mellifera toward the floral extracts from both locations. Our results showed significant differences in chemical composition and sexual morphs; only the hermaphrodite flowers from the Herradero orchard produced limonene and α-pinene and had longer peduncle and sepal than flowers from the Metapa orchard; on the other hand, the hermaphrodite flowers from the Metapa orchard had longer gynoecium. In the behavioral experiment the extracts from the Herradero orchard seemed to give A. mellifera foragers better cues for orientation to food sources, perhaps due to the presence of limonene and α-pinene, which are absent in the samples from Metapa. Such differences in both orchards could affect pollinator attraction and ultimately seed set and productivity.

Chloral hydrate complexing with heteropolyanions of diverse structures

International Nuclear Information System (INIS)

Maksimov, G.M.; Timofeeva, M.N.; Likholobov, V.A.

2001-01-01

Interaction between chloral hydrate and tetrabutylammonium salts of heteropolyacids (HPA) of five structural types: Keggin's (H 3 PW 12 O 40 , H 3 PMo 12 O 40 , H 4 SiW 12 O 40 ), Dowson's (α-H 6 P 2 W 18 O 62 , α-H 6 P 2 Mo 18 O 62 , α-H 4 S 2 Mo 18 O 62 ), H 6 P 2 W 21 O 71 (H 2 O) 3 , H 6 As 2 W 21 O 69 (H 2 O) and H 21 B 3 W 39 O 132 was studied by the method 1 H NMR in deuteronitrobenzene solution. It was ascertained that the surface of HPA anions is heterogeneous in reference to acid-base properties. Dependence general for all HPA was found: decrease in specific charge of anion (per one atom of W or Mo) gives rise to increase in HPA acidity [ru

Tech Support.

Science.gov (United States)

Beem, Kate

2002-01-01

Discusses technology-support issues, including staff training, cost, and outsourcing. Describes how various school districts manage technology-support services. Features the Technology Support Index, developed by the International Society for Technology in Education, to gauge the operation of school district technology-support programs. (PKP)

Social support for diabetes illness management: supporting adolescents and caregivers.

Science.gov (United States)

Idalski Carcone, April; Ellis, Deborah A; Weisz, Arlene; Naar-King, Sylvie

2011-10-01

The aim of this research study was to examine the relationship between 4 sources of social support (support for the adolescent from family, support for the adolescent from friends, support for the caregiver from another adult, and support to the family from the health care provider) and adolescents' diabetes outcomes (illness management behavior and health status) using a diverse sample of urban adolescents. One hundred forty-one adolescents with insulin-managed diabetes and their primary caregivers completed questionnaires assessing social support and illness management behavior. Glucose meters were downloaded and hemoglobin A1c assays were obtained. Structural equation modeling was used to test a model social support informed by social ecological theory. The results of the structural equation modeling indicated that support for the caregiver from another adult was directly and positively related to support for the adolescent from family and indirectly related to better illness management. Support for the adolescent from family was directly related to better diabetes management and, through better management, to better diabetes health. Support to the family from the health care provider was not related to support for the adolescent and support to the adolescent from friends was not related to illness management, as hypothesized. This study identifies a novel target for social support intervention to improve adolescents' illness management behavior-the caregivers of adolescents with diabetes. By enhancing the social support caregivers receive from other adults in their lives, caregivers' ability to support their adolescent children with diabetes might also be improved which, in turn, improves adolescents' illness outcomes.

Journal of Chemical Sciences | Indian Academy of Sciences

Indian Academy of Sciences (India)

Hydrophobic effect of silica functionalized with silylated Ti-salicylaldimine complex on limonene oxidation by aqueous hydrogen peroxide ... Centre for Sustainable Nanomaterials, Ibnu Sina Institute for Scientific and Industrial Research, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor, Malaysia; Department of ...

Antimicrobial activity of essential oils and their components against the three major pathogens of the cultivated button mushroom

NARCIS (Netherlands)

Sokovic, M.; Griensven, van L.J.L.D.

2006-01-01

Essential oils of Matricaria chamommilla, Mentha piperita, M. spicata, Lavandula angusti folia, Ocimum basilicum, Thymus vulgaris, Origanum vulgare, Salvia officinalis, Citrus limon and C. aurantium and their components; linalyl acetate, linalool, limonene, ¿-pinene, ß-pinene, 1,8-cineole, camphor,

Influence of flavour absorption on oxygen permentation through LDPE, PP, PC and PET plastics food packaging

NARCIS (Netherlands)

Willige, van R.W.G.; Linssen, J.P.H.; Meinders, M.B.J.; Stege, van der H.J.; Voragen, A.G.J.

2002-01-01

The effect of flavour absorption on the oxygen permeability of low-density polyethylene (LDPE), polypropylene (PP), polycarbonate (PC) and polyethylene terephthalate (PET) was studied using an isostatic continuous flow system. Polymer samples were exposed to a model solution containing limonene,

Supporting the Support System: How Assessment and Communication Can Help Patients and Their Support Systems.

Science.gov (United States)

Harkey, Jane; Young, Jared; Carter, Jolynne Jo; Demoratz, Michael

The benefits of having a support system, such as social relationships with close friends and family, have been well documented for patients with serious health issues. As scientific evidence has shown, individuals who have the lowest level of involvement in social relationships face a greater mortality risk. Support systems, however, are not infallible. Relationship stress can have a negative impact on people-patient and caregiver alike-behaviorally, psychosocially, and physiologically. The purpose of this article is to encourage case managers who take a patient-centered approach to also consider the existence and extent of the support system, as well as any stresses or tensions that are observable within the support system. Although the case manager is ethically obliged to advocate for the individual receiving case management services, that advocacy can be extended to the support system for the good of all. This discussion applies to numerous case management practices and work settings including (but not limited to) hospital-based case management, home health, geriatrics, catastrophic case management, mental health, palliative care, and end of life/hospice. As part of the assessment phase of the case management process, case managers determine the extent of the patient's support system or social support network such as family and close friends. Although their advocacy is primarily for the patient receiving case management services, case managers also become aware of the needs of the support system members as they face their loved one's serious illness, severe injury, geriatric care demands, or end of life. Case managers can use their communication skills, especially motivational interviewing, with patients and their support systems to identify stresses and issues that can impact the pursuit of health goals. In addition, case managers ensure that individuals and their support systems are kept informed such as about the health condition, stage of disease, plan of

Roadway supports

Energy Technology Data Exchange (ETDEWEB)

Stassen, P

1980-01-01

Support systems in stone drifts and tunnels are discussed. Timber supports, steel arches, cold-bent sheet-metal arches, shotcrete and combined support arrangements are described. Brickwork and reinforced concrete are also covered. Supports in roadways leading to the face and in-seam roads are discussed including timber supports, steel arches, articulated arches on timber chocks, support accessories and the withdrawal and reshaping of arches. The subject of strata bolting, the aims of strata bolting, methods of strata bolting, systems of rock-bolting, end plates and wire mesh, and bolt and anchorage monitoring are also discussed. Injection techniques, injection parameters, injection methods, grouts, includes an example of the application of injection techniques are covered and combined injection/dowelling arrangements are examined. (55 refs.) (In French)

Support system, excavation arrangement, and process of supporting an object

Science.gov (United States)

Arnold, Bill W.

2017-08-01

A support system, an excavation arrangement, and a process of supporting an object are disclosed. The support system includes a weight-bearing device and a camming mechanism positioned below the weight-bearing device. A downward force on the weight-bearing device at least partially secures the camming mechanism to opposing surfaces. The excavation arrangement includes a borehole, a support system positioned within and secured to the borehole, and an object positioned on and supported by the support system. The process includes positioning and securing the support system and positioning the object on the weight-bearing device.

Chemical Composition and Insecticidal Activity of the Essential Oil of Illicium pachyphyllum Fruits against Two Grain Storage Insects

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Hui-Wen Dong

2012-12-01

Full Text Available The aim of this research was to determine chemical composition and insecticidal activity of the essential oil of Illicium pachyphyllum fruits against two grain storage insects, Sitophilus zeamais and Tribolium castaneum, and to isolate any insecticidal constituents from the essential oil. The essential oil of I. pachyphyllum fruits was obtained by hydrodistillation and analyzed by GC-MS. A total of 36 components of the essential oil were identified, with the principal compounds in the essential oil being trans-ρ-mentha-1(7,8-dien-2-ol (24.56%, D-limonene (9.79%, caryophyllene oxide (9.32%, and cis-carveol (5.26% followed by β-caryophyllene (4.63% and bornyl acetate. Based on bioactivity-guided fractionation, the three active constituents were isolated and identified as trans-ρ-mentha-1(7,8-dien-2-ol, D-limonene and caryophyllene oxide. The essential oil of I. pachyphyllum fruits exhibited contact toxicity against S. zeamais and T. castaneum adults, with LD50 values of 17.33 μg/adult and 28.94 μg/adult, respectively. trans-p-Mentha-1(7,8-dien-2-ol (LD50 = 8.66 μg/adult and 13.66 μg/adult, respectively exhibited stronger acute toxicity against S. zeamais and T. castaneum adults than either caryophyllene oxide (LD50 = 34.09 μg/adult and 45.56 μg/adult and D-limonene (LD50 = 29.86 μg/adult and 20.14 μg/adult. The essential oil of I. pachyphyllum possessed fumigant toxicity against S. zeamais and T. castaneum adults with LC50 values of 11.49 mg/L and 15.08 mg/L, respectively. trans-p-Mentha-1(7,8-dien-2-ol exhibited stronger fumigant toxicity against S. zeamais and T. castaneum adults, respectively, with LC50 values of 6.01 mg/L and 8.14 mg/L, than caryophyllene oxide (LC50 = 17.02 mg/L and 15.98 mg/L and D-limonene (LC50 = 33.71 mg/L and 21.24 mg/L. The results indicate that the essential oil of I. pachyphyllum fruits and its constituent compounds have potential for development into natural insecticides or fumigants for the control of

Complex refractive indices in the near-ultraviolet spectral region of biogenic secondary organic aerosol aged with ammonia

Energy Technology Data Exchange (ETDEWEB)

Flores, J. M.; Washenfelder, Rebecca; Adler, Gabriela; Lee, H-J; Segev, Lior; Laskin, Julia; Laskin, Alexander; Nizkorodov, Sergey; Brown, Steven; Rudich, Yinon

2014-05-14

Atmospheric absorption by brown carbon aerosol may play an important role in global radiative forcing. Brown carbon arises from both primary and secondary sources, but the mechanisms and reactions for the latter are highly uncertain. One proposed mechanism is the reaction of ammonia or amino acids with carbonyl products in secondary organic aerosol (SOA). We generated SOA in situ by reacting biogenic alkenes (α-pinene, limonene, and α-humulene) with excess ozone, humidifying the resulting aerosol, and reacting the humidified aerosol with gaseous ammonia. We determined the complex refractive indices (RI) in the 360 – 420 nm range for these aerosols using broadband cavity enhanced spectroscopy (BBCES). The average real part (n) of the measured spectral range of the NH3-aged α-pinene SOA increased from n = 1.50 (±0.01) for the unreacted SOA to n = 1.57 (± 0.01) after a 1.5h exposure to 1.9 ppm NH3; whereas,the imaginary component (k) remained below k < 0.001 (± 0.002). For the limonene and α-humulene SOA the real part did not change significantly, and we observed a small change in the imaginary component of the RI. The imaginary component increased from k = 0.0 to an average k= 0.029 (± 0.021) for α-humulene SOA, and from k < 0.001 (± 0.002) to an average k = 0.032 (±0.019) for limonene SOA after a 1.5 h exposure to 1.3 and 1.9 ppm of NH3, respectively. Collected filter samples of the aged and unreacted α-pinene SOA and limonene SOA were analyzed off-line with nanospray desorption electrospray ionization high resolution mass spectrometry (nano-DESI/HR-MS), and in-situ with a Time-of-Fligh Aerosol Mass Spectrometer, confirming that the SOA reacted and that various nitrogen-containing reaction products formed. If we assume that NH3 aging reactions scale linearly with time and concentration, then a 1.5 h reaction with 1 ppm NH3 in the laboratory is equivalent to 24 h reaction with 63 ppbv NH3, indicating that the observed aerosol absorption will be limited

Characterization of an In Vitro Human Breast Epithelial Organoid System

Science.gov (United States)

1999-08-01

isothiocyanates (in cruciferous vegetables), organosulfur compounds (diallyl disulfide in Allium sp), monoterpenes (D-limonene in citrus fruit oils) and...34. Rao, C. V.; Rivenson, A.; Simi, B.; Reddy, B. S. Chemoprevention of Colon Carcino- genesis by Dietary Curcumin, a Naturally Occurring Plant

Ionic liquid stabilized Rh Nanoparticles for Citral Cyclodehydration

NARCIS (Netherlands)

Quek, X.Y.; Guan, Y.; Santen, van R.A.; Hensen, E.J.M.

2010-01-01

Smells nice, too: The cyclodehydration of citral is achieved by using rhodium nanoparticles dispersed in an imidazolium-based ionic liquid. p-Cymene, p--dimethylstyrene, and limonene are obtained with selectivity greater than 75¿%. The interaction between the imidazolium cations and the metal

Microwave-assisted extraction kinetics of terpenes from caraway seeds

NARCIS (Netherlands)

Chemat, S.; Ait-Amar, H.; Lagha, A.; Esveld, D.C.

2005-01-01

The process conditions during the extraction of carvone and limonene from caraway seed (Carum carvi L.) with microwave-assisted extraction have been studied with respect to microwave power, radiation dose and extraction time in order to obtain the secondary metabolites selectively. Using classical

Heartwood extractives of iranian morus alba wood

International Nuclear Information System (INIS)

Sadeghifar, H.; Sheikh, A.; Khalilzadeh, M.A.; Ebadi, A.G.

2011-01-01

The composition and amount of hydrophilic and lipophilic extractives in heartwood of Morus alba wood in north of Iran were analysed n-Decane (50%), dodecane (9%) and limonene (11%) were main lipophilic components. Resorcinol (about 90%) is main hydrophilic phenolic compound. (author)

Elucidation of density profile of self-assembled sitosterol + oryzanol tubules with small-angle neutron scattering

NARCIS (Netherlands)

Bot, A.; Gilbert, E.P.; Bouwman, W.G.; Sawalha, H.I.M.; Adel, den R.; Garamus, V.M.; Venema, P.; Linden, van der E.; Flöter, E.

2012-01-01

Small-angle neutron scattering (SANS) experiments have been performed on self-assembled tubules of sitosterol and oryzanol in triglyceride oils to investigate details of their structure. Alternative organic phases (deuterated and non-deuterated decane, limonene, castor oil and eugenol) were used to

Antiradical potential and antifungal activities of essential oils of the ...

African Journals Online (AJOL)

STORAGESEVER

2008-11-19

Nov 19, 2008 ... Excellent for health (much vitamin C) (Economos and. Clay, 1999), C. ... hair; it can be applied to the face like refreshing lotion and can also .... after loss of proton. .... D limonene, linalool and crude Citrus oils extracts. Vet. Clin.

Distribution of enantiomers of volatile organic compounds in selected fruit distillates.

Science.gov (United States)

Vyviurska, Olga; Zvrškovcová, Helena; Špánik, Ivan

2017-01-01

The enantiomer ratios of chiral volatile organic compounds in fruit distillates were determined by multidimensional gas chromatography using solid-phase microextraction (SPME) as a sample treatment procedure. Linalool and its oxides, limonene, α-terpineol, and nerolidol, were present at the highest concentration levels, while significantly lower amounts of β-citronellol and lactones were found in the studied samples. However, almost all terpenoids mainly occur as a racemic or near-racemic mixture; enantiomer distribution of some chiral organic compounds in fruit distillates correlated to a botanical origin. In particular, a significant enantiomeric excess of (R)-linalool and (S)-α-terpineol was found only for pear brandy, and likewise the dominance (R)-limonene and the second eluted enantiomer of nerolidol for Sorbus domestica and strawberry, respectively. The distribution of γ-lactones stereoisomers was more nonspecific, with a general excess of the R-enantiomer. © 2016 Wiley Periodicals, Inc.

1-Butyl-3-Methylimidazolium Tetrafluoroborate Film as a Highly Selective Sensing Material for Non-Invasive Detection of Acetone Using a Quartz Crystal Microbalance.

Science.gov (United States)

Tao, Wenyan; Lin, Peng; Liu, Sili; Xie, Qingji; Ke, Shanming; Zeng, Xierong

2017-01-20

Breath acetone serves as a biomarker for diabetes. This article reports 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF₄]), a type of room temperature ionic liquid (RTIL), as a selective sensing material for acetone. The RTIL sensing layer was coated on a quartz crystal microbalance (QCM) for detection. The sensing mechanism is based on a decrease in viscosity and density of the [bmim][BF₄] film due to the solubilization of acetone leading to a positive frequency shift in the QCM. Acetone was detected with a linear range from 7.05 to 750 ppmv. Sensitivity and limit of detection were found to be 3.49 Hz/ppmv and 5.0 ppmv, respectively. The [bmim][BF₄]-modified QCM sensor demonstrated anti-interference ability to commonly found volatile organic compounds in breath, e.g., isoprene, 1,2-pentadiene, d -limonene, and dl -limonene. This technology is useful for applications in non-invasive early diabetic diagnosis.

Cleaning Products and Air Fresheners: Emissions and ResultingConcentrations of Glycol Ethers and Terpenoids

Energy Technology Data Exchange (ETDEWEB)

Singer, Brett C.; Destaillat, Hugo; Hodgson, Alfred T.; Nazaroff,William W.

2005-08-01

Experiments were conducted to quantify emissions and concentrations of glycol ethers and terpenoids from cleaning product and air freshener use in a 50-m{sup 3} room ventilated at {approx}0.5 h{sup -1}. Five cleaning products were applied full-strength (FS); three were additionally used in dilute solution. FS application of pine-oil cleaner (POC) yielded 1-h concentrations of 10-1300 {micro}g m{sup -3} for individual terpenoids, including {alpha}-terpinene (90-120), d-limonene (1000-1100), terpinolene (900-1300), and {alpha}-terpineol (260-700). One-hour concentrations of 2-butoxyethanol and/or dlimonene were 300-6000 {micro}g m{sup -3} after FS use of other products. During FS application including rinsing with sponge and wiping with towels, fractional emissions (mass volatilized/dispensed) of 2-butoxyethanol and d-limonene were 50-100% with towels retained, {approx}25-50% when towels were removed after cleaning. Lower fractions (2-11%) resulted from dilute use. Fractional emissions of terpenes from FS use of POC were {approx}35-70% with towels retained, 20-50% with towels removed. During floor cleaning with dilute solution of POC, 7-12% of dispensed terpenes were emitted. Terpene alcohols were emitted at lower fractions: 7-30% (FS, towels retained), 2-9% (FS, towels removed), and 2-5% (dilute). During air-freshener use, d-limonene, dihydromyrcenol, linalool, linalyl acetate, and {beta}-citronellol were emitted at 35-180 mg d{sup -1} over three days while air concentrations averaged 30-160 {micro}g m{sup -3}.

Waste truck-tyre processing by flash pyrolysis in a conical spouted bed reactor

International Nuclear Information System (INIS)

Lopez, G.; Alvarez, J.; Amutio, M.; Mkhize, N.M.; Danon, B.; Gryp, P.; Görgens, J.F. van der; Bilbao, J.; Olazar, M.

2017-01-01

Highlights: • Flash pyrolysis improves TPO and limonene yields vs. slow pyrolysis. • The most suitable temperature for TPO and limonene maximization was 475 °C. • Operating at 575 °C gas yields and char quality was enhanced. • Temperature showed a limited effect on sulphur distribution among products. - Abstract: The flash pyrolysis of waste truck-tyres was studied in a conical spouted bed reactor (CSBR) operating in continuous regime. The influence of temperature on product distribution was analysed in the 425–575 °C range. A detailed characterization of the pyrolysis products was carried out in order to assess their most feasible application. Moreover, special attention was paid to the sulphur distribution among the products. The analysis of gaseous products was carried out using a micro-GC and the tyre pyrolysis oil (TPO) by means of GC-FID using peak areas for quantification, with GC/MS for identification and elemental analysis. Finally, the char was subjected to elemental analysis and surface characterization. According to the results, 475 °C is an appropriate temperature for the pyrolysis of waste tyres, given that it ensures total devolatilisation of tyre rubber and a high TPO yield, 58.2 wt.%. Moreover, the quality of the oil is optimum at this temperature, especially in terms of high concentrations of valuable chemicals, such as limonene. An increase in temperature to 575 °C reduced the TPO yield to 53.9 wt.% and substantially changed its chemical composition by increasing the aromatic content. However, the quality of the recovered char was improved at high temperatures.

Volatile components of essential oil from cultivated Myrica gale var. tomentosa and its antioxidant and antimicrobial activities.

Science.gov (United States)

Nakata, Mayuko; Myoda, Takao; Wakita, Yoichi; Sato, Takahiro; Tanahashi, Ikuko; Toeda, Kazuki; Fujimori, Takane; Nishizawa, Makoto

2013-01-01

Aromatic components in the essential oil prepared from the leaves of cultivated Myrica gale var. tomentosa were compared with those from oil derived wild plants by using gas chromatography-mass spectroscopy (GC/MS). We found that essential oils from both the wild and cultivated plants contained similar aromatic components such as β-elemenone, selina 3,7(11)-diene, myrcene, limonene, cymene, 1,8-cineole, and β-pinene, but the content ratio of the oil was significantly different, which might yield differences in the aromatic properties. The aroma impact components of the essential oils were also determined using GC/MS-Olfactometry (GC/MS-O) and aroma extract dilution analysis. Eight aromatic compounds, including linalool, limonene, and 1,8-cineole, were shown to contribute to the aromatic properties of cultivated M. gale var. tomentosa. The strongest aromatic note was defined as linalool, followed by limonene, 1,8-cineole, and β-elemenone. The essential oil, ethanol (EtOH), 1,3-butylene glycol (BG), and 1,3-propanediol (PD) extracts prepared from the leaves of cultivated M. gale var. tomentosa also showed antioxidant and antimicrobial activities, that is, they demonstrated scavenger activity against hydroxyl and superoxide radicals in the aqueous phase, and showed inhibitory effects on lipid peroxidation. The essential oil extracts also exhibited antimicrobial activity against gram-positive bacteria, with the lowest minimum inhibitory concentration value against Bacillus subtilis. In conclusion, the essential oil and solvent extracts from cultivated M. gala var. tomentosa have a potential for utilization as food and cosmetic ingredients.

Photochromic and thermal properties of poly(vinyl alcohol)/H6P2W18O62 hybrid membranes

International Nuclear Information System (INIS)

Gong Jian; Li Xiangdan; Shao Changlu; Ding Bin; Lee, Douk-Rae; Kim, Hak-Yong

2003-01-01

Poly(vinyl alcohol) (PVA) films, which contained different content of heteropolyacid (HPA) with Dawson-Wells structure, were prepared. The photochromic behavior was investigated by using ultraviolet-visible (UV-Vis) absorption spectroscopy. The result indicated that the film was reduced photochemically to yield a blue species under UV irradiation, and the color of the film changed to deep blue with increasing irradiation time and HPA content. The photochromic sensibility of different UV wavelength was investigated. In the UV-Vis spectra of the irradiated films, an isobestic point was observed at about 352 nm. The reduction mechanism of the heteropolyanion (W 6+ →W 5+ ) was suggested. The thermal property and the conductivity of the film were also studied. The thermal degradation step and the melting point of the film were influenced by different content of the HPA. Notably, the conductivity of 8.33x10 -6 S cm -1 was observed when the HPA content was 80 wt.%

Light energy conversion by photocatalytic reaction

Energy Technology Data Exchange (ETDEWEB)

Fujishima, Akira; Yamagata, Sadamu [Univ. of Tokyo (Japan)

1989-01-01

The photocatalytic reaction, to be made to a suspended semiconductor powder system, was explained in summary. By using semiconductor as an electrode for the electrolyzation, etc. and projecting light on it to generate photoelectromotive force, a photocell can be composed. eg., by composing titanium oxide electrode, n-type semiconductor and platinum electrode, and irradiating light on the former electrode to generate electric current, oxygen and hydrogen are produced from the titanium oxide electrode and platinum electrode, respectively, which means the possibility of obtainment of clean energy from water as raw material. Such a wet type photocell, easy to produce, is active also in research. With white titanium oxide powder being suspended in water solution, hydrogen is produced by projecting light into it. Such a semiconductor is called photocatalyst, in which the research has been widely developed, mainly by taking notice of the hydrogen production on reduction side, since 1972. The photocatalysis using colloid and, differently, that doing heteropolyacid are also taken notice of. 24 refs., 6 figs.