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1.
Plant Foods Hum Nutr ; 78(4): 768-775, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37819493

RESUMEN

Parkinson's disease (PD) is an incurable neurodegenerative disease characterized by motor and non-motor disabilities resulting from neuronal cell death in the substantia nigra and striatum. Microglial activation and oxidative stress are two of the primary mechanisms driving that neuronal death. Here, we evaluated the effects of geranium oil on 1-methyl-4-phenyl-1,2,3,6-tetra-hydropyridine (MPTP) mouse model for PD, on microglial activation, and oxidative stress. We demonstrate that oral treatment with geranium oil improved motor performance in this model. The therapeutic effects of geranium oil were observed as a significant increase in rotarod latency and distance among the mice treated with geranium oil, as compared to vehicle-treated MPTP mice. Geranium oil also prevented dopaminergic neuron death in the substantia nigra of the treated mice. These therapeutic effects can be partially attributed to the antioxidant and anti-inflammatory properties of geranium oil, which were observed as attenuated accumulation of reactive oxygen species and inhibition of the secretion of proinflammatory cytokines from geranium oil-treated activated microglial cells. A repeated-dose oral toxicity study showed that geranium oil is not toxic to mice. In light of that finding and since geranium oil is defined by the FDA as generally recognized as safe (GRAS), we do not foresee any toxicity problems in the future and suggest that geranium oil may be a safe and effective oral treatment for PD. Since the MPTP model is only one of the preclinical models for PD, further studies are needed to confirm that geranium oil can be used to prevent or treat PD.


Asunto(s)
Geranium , Enfermedades Neurodegenerativas , Enfermedad de Parkinson , Animales , Ratones , Enfermedades Neurodegenerativas/metabolismo , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/metabolismo , Sustancia Negra/metabolismo , Muerte Celular , Ratones Endogámicos C57BL , Modelos Animales de Enfermedad
2.
J Environ Qual ; 40(5): 1405-15, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21869502

RESUMEN

Malodor emissions limit public acceptance of using municipal biosolids as natural organic resources in agricultural production. We aimed to identify major odorants and to evaluate odor concentrations associated with land application of anaerobically digested sewage sludges (Class B) and their alkaline (lime and coal fly ash)-stabilized products (Class A). These two types of biosolids were applied at 12.6 tonnes ha(-1) (dry weight) to microplots of very fine clayey Vertisol in the Jezreel Valley, northern Israel. The volatile organic compounds (VOCs) emitted from the biosolids before and during alkaline stabilization and after incorporation into the soil were analyzed by headspace solid-phase microextraction followed by gas chromatography-mass spectrometry. Odor concentrations at the plots were evaluated on site with a Nasal Ranger field olfactometer that sniffed over a defined land surface area through a static chamber. The odors emitted by anaerobically digested sewage sludges from three activated sludge water treatment plants had one characteristic chemical fingerprint. Alkaline stabilization emitted substantial odors associated with high concentrations of ammonia and release of nitrogen-containing VOCs and did not effectively reduce the potential odor annoyance. Odorous VOCs could be generated within the soil after biosolids incorporation, presumably because of anaerobic conditions within soil-biosolids aggregates. We propose that dimethyl disulfide and dimethyl trisulfide, which seem to be most related to the odor concentrations of biosolids-treated soil, be used as potential chemical markers for the odor annoyance associated with incorporation of anaerobically digested sewage sludges.


Asunto(s)
Compuestos de Calcio , Carbono , Carbón Mineral , Odorantes , Óxidos , Material Particulado , Aguas del Alcantarillado , Ceniza del Carbón , Cromatografía de Gases y Espectrometría de Masas , Compuestos Orgánicos Volátiles/análisis
3.
J Air Waste Manag Assoc ; 61(12): 1353-60, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22263423

RESUMEN

Field odor assessors are required to rate or describe several odor parameters, such as intensity, duration, offensiveness, and character. Ideally, their assessments should reflect the average odor perception of a specific community. The authors developed a three-part screening test for recruiting odor assessors: (1) distinguishing between different odorants by means of a triangular forced-choice test; (2) evaluating odor intensity; and (3) describing hedonic tone and odor character. Grading was based on two criteria: correctly answering the relevant parts of the test, and evaluation of odor parameters relative to the entire tested population. The latter involved grading each tested individual according to the similarity of their score to the average result of 179 tested individuals, comprising 48% women and 52% men whose age and residence distributions were identical between women and men (except for the oldest group). To exclude relatively less sensitive individuals who showed poor ability to distinguish between different odorants and various odor intensities, and/or provided atypical description (or rating) of odor intensity, character, and offensiveness, it was suggested that only individuals whose final score was within the upper 75% (final score +/- 80.75) would be qualified as odor assessors. According to this criterion, 73.8% of men and 78.6% of women passed the test. Among urban and rural dwellers, 77.4% and 67.4%, respectively, were qualified. Pass rate clearly diminished with increasing age: from 89.3% at 21-30 years to 54.6% at 61-70 years. This screening tool is recommended by the Israel Ministry of Environmental Protection for selection of field odor assessors to serve the general community and regulatory authorities.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Odorantes/análisis , Adulto , Anciano , Femenino , Humanos , Israel , Masculino , Persona de Mediana Edad , Percepción , Encuestas y Cuestionarios , Adulto Joven
4.
Phytochemistry ; 69(14): 2565-71, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18834605

RESUMEN

Selected plants within the Origanum, Mentha and Salvia genera, that contain significant amounts of chiral volatile alcohols and their related acetates, exhibit remarkable enantioselectivity of alcohol acetyl transferase (AAT) activity and particularly can discriminate between linalool enantiomers. Origanum dayi AAT produced almost enantiomerically pure (R)-linalyl acetate by enzymatic acetylation of racemic linalool, whereas the closely related O. majorana AAT produced a mixture of (R)- and (S)-linalyl acetate with a ratio of 6:4. V(max) of O. dayi acetylation activity was 30-fold higher for (R)-linalool, whereas in O. majorana no such differences were found.


Asunto(s)
Acetiltransferasas/metabolismo , Alcoholes/metabolismo , Mentha/enzimología , Monoterpenos/metabolismo , Origanum/enzimología , Salvia/enzimología , Acetilación , Monoterpenos Acíclicos , Estructura Molecular , Aceites Volátiles/metabolismo , Hojas de la Planta/metabolismo , Especificidad por Sustrato , Compuestos Orgánicos Volátiles
5.
J Air Waste Manag Assoc ; 58(9): 1187-97, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18817111

RESUMEN

Livestock operations are associated with emissions of odor, gases, and particulate matter. The majority of previous livestock odor studies focused on swine operations whereas relatively few relate to dairy cattle. Identifying the compounds responsible for the primary odor impact is a demanding analytical challenge because many critical odor components are frequently present at very low concentrations within a complex matrix of numerous insignificant volatiles. The objective of this study was to describe a chemical-sensory profile of dairy manure odor using headspace solid-phase microextraction (HS-SPME) and multidimensional gas chromatography-mass spectrometry-olfactometry (MDGC-MS-O). Two analytical approaches were used: (1) HS-SPME time-series extractions (from seconds up to 20 hr) followed by gas chromatography-mass spectrometry-olfactometry (GC-MS-O) analyses, and (2) relatively short HS-SPME extractions (30 min) followed by MDGC-MS-O analyses on selected chromatogram heart-cuts. Dairy manure was collected at research dairy farms in the United States and Israel. Volatile organic compounds (VOCs) resolved from multiple analyses included sulfur-containing compounds, volatile fatty acids, ketones, esters, and phenol/indole derivatives. A total of 86 potential odorants were identified. Of them, 17 compounds were detected by the human nose only. A greater number of VOCs and odorous compounds were detected, as well as higher mass loading, on solid-phase microextraction (SPME) fibers observed for longer extractions with SPME. However, besides sulfur-containing compounds, other selected compounds showed no apparent competition and displacement on the SPME fiber. The use of MDGC-MS-O increased chromatographic resolution even at relatively short extractions and revealed 22 additional odorants in one of the regions of the chromatogram. The two analytical approaches were found to be parallel to some extent whereas MDGC-MS-O can also be considered as a complementary approach by resolving more detailed chemical-sensory odor profiles.


Asunto(s)
Contaminantes Ocupacionales del Aire/análisis , Industria Lechera , Estiércol/análisis , Odorantes/análisis , Odorantes/prevención & control , Animales , Bovinos , Cromatografía de Gases y Espectrometría de Masas , Humanos , Microextracción en Fase Sólida
6.
World J Gastroenterol ; 13(3): 361-8, 2007 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-17230603

RESUMEN

AIM: To evaluate the effects of different types of dietary fats on the hepatic lipid content and oxidative stress parameters in rat liver with experimental non-alcoholic fatty liver disease (NAFLD). METHODS: A total of 32 Sprague-Dawley rats were randomly divided into five groups. The rats in the control group (n = 8) were on chow diet (Group 1), rats (n = 6) on methionine choline-deficient diet (MCDD) (Group 2), rats (n = 6) on MCDD enriched with olive oil (Group 3), rats (n = 6) on MCDD with fish oil (Group 4) and rats (n = 6) on MCDD with butter fat (Group 5). After 2 mo, blood and liver sections were examined for lipids composition and oxidative stress parameters. RESULTS: The liver weight/rat weight ratio increased in all treatment groups as compared with the control group. Severe fatty liver was seen in MCDD + fish oil and in MCDD + butter fat groups, but not in MCDD and MCDD + olive oil groups. The increase in hepatic triglycerides (TG) levels was blunted by 30% in MCDD + olive oil group (0.59 +/- 0.09) compared with MCDD group (0.85 +/- 0.04, P < 0.004), by 37% compared with MCDD + fish oil group (0.95 +/- 0.07, P < 0.001), and by 33% compared with MCDD + butter group (0.09 +/- 0.1, P < 0.01). The increase in serum TG was lowered by 10% in MCDD + olive oil group (0.9 +/- 0.07) compared with MCDD group (1.05 +/- 0.06). Hepatic cholesterol increased by 15-fold in MCDD group [(0.08 +/- 0.02, this increment was blunted by 21% in MCDD + fish oil group (0.09 +/- 0.02)]. In comparison with the control group, ratio of long-chain polyunsaturated fatty acids omega-6/omega-3 increased in MCDD + olive oil, MCDD + fish oil and MCDD + butter fat groups by 345-, 30- and 397-fold, respectively. In comparison to MCDD group (1.58 +/- 0.08), hepatic MDA contents in MCDD + olive oil (3.3 +/- 0.6), MCDD + fish oil (3.0 +/- 0.4), and MCDD + butter group (2.9 +/- 0.36) were increased by 108%, 91% and 87%, respectively (P < 0.004). Hepatic paraoxonase activity decreased significantly in all treatment groups, mostly with MCDD + olive oil group (-68%). CONCLUSION: Olive oil decreases the accumulation of triglyceride in the liver of rats with NAFLD, but does not provide the greatest antioxidant activity.


Asunto(s)
Grasas de la Dieta/metabolismo , Hígado Graso/metabolismo , Metabolismo de los Lípidos , Hígado/metabolismo , Estrés Oxidativo/fisiología , Animales , Antioxidantes/metabolismo , Peso Corporal , Ácidos Grasos/metabolismo , Hígado Graso/patología , Lípidos/sangre , Hígado/patología , Tamaño de los Órganos , Ratas , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismo
7.
J Agric Food Chem ; 53(18): 7198-203, 2005 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-16131130

RESUMEN

Apple (Malus domestica Borkh.) cultivars differ in their aroma and composition of volatile acetates in their fruit flesh and peel. Cv. Fuji flesh contains substantial levels of 2-methyl butyl acetate (fruity banana-like odor), while the flesh of cv. Granny Smith apples lacks this compound. Granny Smith apples accumulate mainly hexyl acetate (apple-pear odor) in their peel. Feeding experiments indicated that Fuji apples were able to convert hexanol and 2-methyl butanol to their respective acetate derivatives in vivo, while Granny Smith apples could only convert exogenous hexanol to hexyl acetate. Differential substrate specificities of the in vitro acetyl-CoA:alcohol acetyl transferase (AAT) activities were also detected among cultivars. In Granny Smith apples, the AAT activity was detected only in the peel, and its specificity was almost exclusively restricted to hexanol and cis-3-hexenol. In Fuji apples, the AAT activity was detected in both peel and flesh and apparently accepted a broader range of alcohols as substrates than the Granny Smith enzyme activity. Our data strongly suggest that different AAT activities are operational in apple tissues and cultivars and that these differences contribute to the variation observed in the accumulation of volatile acetates.


Asunto(s)
Acetilcoenzima A/metabolismo , Acetiltransferasas/metabolismo , Ésteres/metabolismo , Frutas/enzimología , Malus/enzimología , Cromatografía de Gases y Espectrometría de Masas , Volatilización
8.
J Biotechnol ; 105(1-2): 61-70, 2003 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-14511910

RESUMEN

Propenylbenzenes are often used as starting materials in the chemical synthesis of aroma compounds and fine chemicals. In the present study, we demonstrate the ability of an Arthrobacter sp. to transform various structures of propenylbenzenes derived from essential oils to flavor, fragrance, and fine chemicals. Arthrobacter strain TA13 and its t-anethole blocked mutants (incapable of growing on t-anethole) converted isoeugenol to vanillin and vanillic acid; and safrole to hydroxychavicol. High conversion efficiencies were achieved in the biotransformations of isosafrole to piperonylic acid, and eugenol to a mixture of ferulic acid and vanillic acid. In addition, anisic acid was produced in high yields from t-anethole, anisyl alcohol, or anisaldehyde. The accumulation of the corresponding aromatic acids from the tested propenylbenzenes is due to the lack of m-demethylase activity in strain TA13 that prevents further cleavage of the benzene ring. Interestingly, in the transformation of eugenol (a 2-propenylbenzene) the side chain was initially oxidized to the corresponding cinamic acid derivative (ferulic acid) while the 1-propenylbenzenes gave substituted benzoic acids, suggesting two different chain shortening mechanisms.


Asunto(s)
Anisoles/metabolismo , Arthrobacter/metabolismo , Biotransformación , Aceites Volátiles/metabolismo , Derivados de Alilbenceno , Benzoatos/metabolismo , Ácidos Cumáricos/metabolismo , Mutación , Aceites Volátiles/química , Ácido Vanílico/metabolismo
9.
J Agric Food Chem ; 50(15): 4251-6, 2002 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-12105954

RESUMEN

The rapidly ripening summer apple cultivar Anna was treated with 0.1 micro L(-1) and 1 microL L(-1) 1-methylcyclopropene (MCP) at harvest and kept at 20 degrees C, or stored for 5 weeks at 0 degrees C and then transferred to 20 degrees C. Total volatiles were not reduced by treatment with 0.1 microL L(-1) MCP, but were 70% lower in fruits treated with 1 microL L(-1) MCP than in untreated fruits. Ethylene production was 50% and 95% inhibited by 0.1 microL L(-1) and 1 microL L(-1) MCP, respectively. The volatiles produced by fruit at harvest were predominantly aldehydes and alcohols, with some acetate esters as well as 2-methyl butyl acetate and beta-damascenone. During ripening, the acetate and butyrate esters increased greatly and alcohols and aldehydes decreased. MCP-treated apples retained more alcohols, aldehydes, and beta-damascenone volatiles than did untreated apples. Sensory evaluation found that control and 0.1 microL L(-1) treated apples developed more fruity, ripe, and overall aromas, but the preference was for the 1 microL L(-1) treated apples with a less ripe aroma.


Asunto(s)
Ciclopropanos/farmacología , Malus/metabolismo , Odorantes , Alcoholes/metabolismo , Aldehídos/metabolismo , Etilenos/metabolismo , Conservación de Alimentos , Frutas/metabolismo , Humanos , Olfato , Volatilización
10.
J Agric Food Chem ; 50(7): 2005-9, 2002 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-11902948

RESUMEN

Vegetable cultivation favored the inclusion of pleasant aromas in the produce, whereas unpleasant aromas were selected against. Introgression lines, generated by hybridization of a cultivated tomato (Lycopersicon esculentum) to its wild relative L. pennellii, were used to map quantitative trait loci (QTL) that influence tomato aroma. A marked undesirable flavor was detected by taste panelists in L. pennellii fruits and was related to an introgressed segment from the short arm of chromosome 8. Analysis of the ripe fruits' volatiles of chromosome 8 introgressed lines revealed an up to 60-fold increase in the levels of 2-phenylethanol and phenylacetaldehyde, as compared to the cultivated tomato. This effect was associated with a 10 cM segment originating from the wild species. Although 2-phenylethanol and phenylacetaldehyde have favorable contribution to tomato aroma when present at low levels, phenylacetaldehyde has a nauseating objectionable aroma when present in levels >0.005 ppm. The loss of the ability to produce high levels of phenylacetaldehyde contributed to the development of desirable aroma of the cultivated tomato. The findings provide a genetic explanation for one of the aroma changes that occurred during the domestication of the tomato.


Asunto(s)
Acetaldehído/análogos & derivados , Odorantes , Selección Genética , Solanum lycopersicum/genética , Acetaldehído/análisis , Alelos , Mapeo Cromosómico , Genes de Plantas , Alcohol Feniletílico/análisis , Gusto , Volatilización
11.
J Agric Food Chem ; 50(14): 4025-30, 2002 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-12083877

RESUMEN

Among the most important volatile compounds in the aroma of strawberries are 2,5-dimethyl-4-hydroxy-3(2H)-furanone (Furaneol) and its methoxy derivative (methoxyfuraneol, mesifuran). Three strawberry varieties, Malach, Tamar, and Yael, were assessed for total volatiles, Furaneol, and methoxyfuraneol. The content of these compounds sharply increased during fruit ripening, with maximum values at the ripe stage. An enzymatic activity that transfers a methyl group from S-adenosylmethionine (SAM) to Furaneol sharply increases during ripening of strawberry fruits. The in vitro generated methoxyfuraneol was identified by radio-TLC and GC-MS. The partially purified enzyme had a native molecular mass of approximately 80 kDa, with optimum activity at pH 8.5 and 37 degrees C. A high apparent K(m) of 5 mM was calculated for Furaneol, whereas this enzyme preparation apparently accepted as substrates other o-dihydroxyphenol derivatives (such as catechol, caffeic acid, and protocatechuic aldehyde) with much higher affinities (K(m) approximately 105, 130, and 20 microM, respectively). A K(m) for SAM was found to be approximately 5 microM, regardless of the acceptor used. Substrates that contained a phenolic group with only one OH group, such as p-coumaric and trans-ferulic acid, as well as trans-anol and coniferyl alcohol, were apparently not accepted by this activity. It is suggested that Furaneol methylation is mediated by an O-methyltransferase activity and that this activity increases during fruit ripening.


Asunto(s)
Frutas/enzimología , Furanos/metabolismo , Metiltransferasas/metabolismo , Odorantes , Rosaceae/enzimología , Cromatografía en Capa Delgada , Cromatografía de Gases y Espectrometría de Masas , Concentración de Iones de Hidrógeno , Metilación , Metiltransferasas/química , Peso Molecular , Especificidad por Sustrato
12.
Pest Manag Sci ; 67(12): 1493-8, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21604353

RESUMEN

BACKGROUND: Ecdysteroids are steroid hormones that control moulting and govern several changes during metamorphoses in arthropods. The discovery of the same molecules (phytoecdysteroids) in several plant species displayed a wide array of rather beneficial agricultural impact. Many representatives of the genus Ajuga plants contain phytoecdysteroids with a 5ß-7-ene-6-one system exhibiting physiological activities in insects. RESULTS: By means of chromatographic (silica gel column, TLC) and LC-MS, two major ecdysteroids (20-hydroxyecdysone and cyasterone) have been isolated and identified from Israeli carpet bugle Ajuga iva (L.) Schreber (Lamiales: Lamiaceae) plants. Ajuga iva extract fractionated on the silica gel column yielded two fractions that showed high activity against the sweetpotato whitefly Bemisis tabaci and the persea mite Oligonychus perseae. A dose of 5 mg AI L(-1) of the purely identified A. iva ecdysterone significantly reduced fecundity, fertility and survival of these pests, while commercial 20-hydroxyecdysone at the same dose had lesser effects. CONCLUSION: The results demonstrate considerable efficacy of natural phytoecdysteroids against major agricultural pests, and suggests that these materials should be considered for potential development of friendly control agents.


Asunto(s)
Ajuga/química , Ecdisteroides/aislamiento & purificación , Hemípteros/efectos de los fármacos , Control de Insectos , Ácaros/efectos de los fármacos , Animales , Fraccionamiento Químico , Ecdisteroides/farmacología , Femenino , Fertilidad/efectos de los fármacos , Reguladores del Crecimiento de las Plantas/aislamiento & purificación , Reguladores del Crecimiento de las Plantas/farmacología , Estigmasterol/análogos & derivados , Estigmasterol/aislamiento & purificación , Estigmasterol/farmacología
13.
J Agric Food Chem ; 57(15): 6636-41, 2009 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-19722569

RESUMEN

Oxidative stress has been implicated in pathologic processes associated with neurodegenerative diseases. Astrocytes, the most abundant glial cell type in the brain, protect neurons from reactive oxygen species (ROS), and any damage to them will affect neuronal survival. This study compares the ability of essential oils prepared from different herbs and spices to protect cultured primary brain astrocytes from H2O2-induced death. The results show that the essential oil of Salvia fruticosa (Sf) among the tested essential oils demonstrated remarkable protective activity. The protective effect of Sf could be attributed to alpha-humulene and alpha-pinene. Following incubation, alpha-humulene and trans-beta-caryophyllene could be found in the cytosol of astrocytes. It is proposed that Sf, by attenuating H2O2-induced cell death, might be used as a functional food or may be offered as a means of therapy in the treatment of neurodegenerative diseases.


Asunto(s)
Astrocitos/citología , Peróxido de Hidrógeno/farmacología , Aceites Volátiles/farmacología , Sustancias Protectoras/farmacología , Salvia/química , Animales , Astrocitos/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Aceites de Plantas/farmacología , Ratas , Ratas Wistar
14.
J Food Prot ; 58(1): 81-85, 1995 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31121777

RESUMEN

Essential oils from oregano and thyme were applied for 24 h as fumigants against the mycelia and spores of Aspergillus flavus , Aspergillus niger and Aspergillus ochraceus , as well as against natural microflora of wheat grains. The minimal inhibitory concentration (MIC) of oregano oil needed to inhibit the mycelial growth of the fungi was 2.0 µl/L, while spores were eradicated following exposure to 2.0 to 2.5 µl/L. The thyme essential oil was less efficient in controlling mycelia and growth was observed even following exposure to 4.0 µl/L. However, the thyme essential oil was fungitoxic to spores (MIC = 3.0 µl/L). In another set of trials the efficacy of the oils and two of their constituents (carvacrol and thymol) in controlling natural microflora of surface-sterilized wheat grain was studied. Of the four materials investigated, only oregano essential oil exhibited fungicidal activity and, following 24 h exposure to 20 µl/L, a significant reduction in the percent of infested grain was observed even after 5 days of incubation on potato dextrose agar. A reduction in the germinability of the grains was evident following exposure to the materials tested. When the fungicidal activity of oregano essential oil was evaluated using grains with different moisture contents (MC), data revealed that the better inhibitory effect was achieved in grain with a high MC. The findings emphasize the toxicity of oregano and thyme essential oils as fumigants against fungi attacking stored grain and strengthen the possibility of using them as an alternative to chemicals for preserving stored grains.

15.
J Biol Chem ; 277(14): 11866-72, 2002 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-11805095

RESUMEN

A bacterial strain (TA13) capable of utilizing t-anethole as the sole carbon source was isolated from soil. The strain was identified as Arthrobacter aurescens based on its 16 S rRNA gene sequence. Key steps of the degradation pathway of t-anethole were identified by the use of t-anethole-blocked mutants and specific inducible enzymatic activities. In addition to t-anethole, strain TA13 is capable of utilizing anisic acid, anisaldehyde, and anisic alcohol as the sole carbon source. t-Anethole-blocked mutants were obtained following mutagenesis and penicillin enrichment. Some of these blocked mutants, accumulated in the presence of t-anethole quantitative amounts of t-anethole-diol, anisic acid, and 4,6-dicarboxy-2-pyrone and traces of anisic alcohol and anisaldehyde. Enzymatic activities induced by t-anethole included: 4-methoxybenzoate O-demethylase, p-hydroxybenzoate 3-hydroxylase, and protocatechuate-4,5-dioxygenase. These findings indicate that t-anethole is metabolized to protocatechuic acid through t-anethole-diol, anisaldehyde, anisic acid, and p-hydroxybenzoic acid. The protocatechuic acid is then cleaved by protocatechuate-4,5-dioxygenase to yield 2-hydroxy-4-carboxy muconate-semialdehyde. Results from inducible uptake ability and enzymatic assays indicate that at least three regulatory units are involved in the t-anethole degradation pathway. These findings provide new routes for environmental friendly production processes of valuable aromatic chemicals via bioconversion of phenylpropenoids.


Asunto(s)
Anisoles/metabolismo , Arthrobacter/metabolismo , Ácido Vanílico/análogos & derivados , Derivados de Alilbenceno , Benzaldehídos/metabolismo , Carbono/metabolismo , Sistema Libre de Células , Cromatografía en Capa Delgada , Éteres de Hidroxibenzoatos , Hidroxibenzoatos/metabolismo , Espectroscopía de Resonancia Magnética , Modelos Químicos , Mutación , Unión Proteica , ARN Ribosómico 16S/metabolismo , Factores de Tiempo , Ácido Vanílico/metabolismo
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