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1.
J Chem Ecol ; 48(9-10): 704-717, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36229713

RESUMEN

A diversity of aquatic organisms manage predation risk by avoiding waters activated with conspecific alarm cues, a chemical mixture released from injuries. The sea lamprey (Petromyzon marinus) is a nocturnal migratory species that relies on its alarm cue to navigate around areas of predation risk when moving through river channels. Identification of the cue's chemistry would allow managers to harness this innate behavioral response to guide migrating sea lamprey to traps (invasive population in the Laurentian Great Lakes) or to fish passage devices where dams block migrations in their native range. We pursued isolation of the sea lamprey alarm cue through behaviorally guided fractionation, fractionating the alarm cue into water-soluble and chloroform-soluble fractions, each of which elicited a substantial avoidance response. Recombining the two fractions restored full reactivity, suggesting the alarm cue mixture contains components that exhibit high solubility in water (e.g., nitrogenous compounds), chloroform (e.g., lipids), or perhaps materials that dissolve readily in either solvent. We further screened 13 individual compounds or pure isolates and 6 sub-fractions from the water-soluble fraction and found one of the pure isolates, isoleucine, evoked an avoidance response on its own, but not consistently when found in other mixtures. In a third experiment, we observed no behavioral response after recombining 32 compounds isolated and identified from the water-soluble fraction. These results confirm other suggestions that the process of elucidating alarm cue constituents is challenging. However, we suggest the pursuit is worthwhile given the strong evidence for the utility of alarm cues for use in the conservation and management of fishes and other aquatic organisms.


Asunto(s)
Petromyzon , Animales , Petromyzon/fisiología , Señales (Psicología) , Cloroformo , Agua , Peces
2.
Sci Rep ; 12(1): 17400, 2022 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-36253421

RESUMEN

Fish use odor to avoid exposure to predation and disease. Harnessing these odors as repellents is proving useful for management initiatives that conserve native species or control invasive populations. Here, we evaluated the behavioral response of invasive sea lamprey to putrescine, a decay molecule that many prey organisms avoid. Putrescine is found in tissue extracts that contain sea lamprey alarm cue, and human saliva, two mixtures known to elicit flight and avoidance responses in migratory sea lamprey. We used two behavioral assays to evaluate metrics of repellency: behavioral preference (space use) and change in activity rates and found context-dependent results. In smaller assays with individual fish, we found that putrescine had no effect on sea lamprey activity but did induce avoidance. In larger assays with multiple animals, sea lamprey did not avoid putrescine. Our results also showed consistent changes in activity and avoidance behavior in sea lamprey exposed to alarm cue in the smaller assay, concluding that this design could prove useful as a high-throughput screening tool. We also investigated a novel odor identified in sea lamprey skin, petromyzonacil, and found no behavioral effects to this odor on its own or in synergy with putrescine. Our results show limited evidence that putrescine acts as robust repellent for sea lamprey and highlight the importance of environmental context when interpreting avoidance behavior in laboratory settings.


Asunto(s)
Petromyzon , Animales , Humanos , Odorantes , Petromyzon/fisiología , Conducta Predatoria , Putrescina/farmacología , Extractos de Tejidos
3.
PLoS One ; 17(1): e0258980, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35085233

RESUMEN

In this study, 5 sterols were isolated and purified from Laminaria japonica, commonly known as edible brown seaweed, and their structures were identified based on detailed chemical methods and spectroscopic analyses. Spectroscopic analyses characterized 5 sterols as 29-Hydroperoxy-stigmasta-5,24(28)-dien-3ß-ol, saringosterol (24-vinyl-cholest-5-ene-3ß,24-diol), 24-methylenecholesterol, fucosterol (stigmasta-5,24-diene-3ß-ol), and 24-Hydroperoxy-24-vinyl-cholesterol. The bioactivities of these sterols were tested using lipid peroxidation (LPO) and cyclooxygenase (COX-1 and -2) enzyme inhibitory assays. Fucosterol exhibited the highest COX-1 and -2 enzyme inhibitory activities at 59 and 47%, respectively. Saringosterol, 24-methylenecholesterol and fucosterol showed higher LPO inhibitory activity at >50% than the other compounds. In addition, the results of molecular docking revealed that the 5 sterols were located in different pocket of COX-1 and -2 and fucosterol with tetracyclic skeletons and olefin methine achieved the highest binding energy (-7.85 and -9.02 kcal/mol) through hydrophobic interactions and hydrogen bond. Our results confirm the presence of 5 sterols in L. japonica and its significant anti-inflammatory and antioxidant activity.


Asunto(s)
Colesterol/análogos & derivados , Inhibidores de la Ciclooxigenasa/farmacología , Laminaria/química , Peroxidación de Lípido/efectos de los fármacos , Esteroles/farmacología , Colesterol/química , Colesterol/farmacología , Ciclooxigenasa 1/química , Ciclooxigenasa 1/metabolismo , Ciclooxigenasa 2/química , Ciclooxigenasa 2/metabolismo , Inhibidores de la Ciclooxigenasa/química , Humanos , Simulación del Acoplamiento Molecular , Estructura Molecular , Conformación Proteica , Esteroles/química , Estigmasterol/análogos & derivados , Estigmasterol/química , Estigmasterol/farmacología
4.
Nat Prod Res ; 36(18): 4725-4729, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34781791

RESUMEN

Several phenanthrenes (1-5), phenolics (6-8) and steroidal sapogenins (9-11) were isolated for the first time from the aqueous and methanolic extracts of Dioscorea sansibarensis Pax yam collected from Tanzania. Chemical structures of all the isolates (1-11) were determined by using 1D and 2D nuclear magnetic resonance spectral methods. All pure isolates were evaluated for anti-inflammatory activity using in vitro cyclooxygenase enzyme (COX-1 and -2) inhibitory assays. Among the isolates tested, phenanthrenes 3-5 showed the highest COX-1 and -2 enzyme inhibitory activity whereas phenolics (6-8) and steroidal sapogenins (9-11) exhibited moderate inhibition when compared to non-steroidal anti-inflammatory drugs aspirin, ibuprofen and naproxen. Compounds 6-11 were evaluated for antioxidant activity using lipid peroxidation inhibitory (LPO) assay for the first time and exhibited moderate LPO inhibition.


Asunto(s)
Dioscorea , Fenantrenos , Sapogeninas , Antiinflamatorios/farmacología , Ciclooxigenasa 1 , Ciclooxigenasa 2 , Dioscorea/química , Peroxidación de Lípido , Fenantrenos/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Sapogeninas/farmacología , Esteroides/farmacología , Tanzanía
5.
PLoS One ; 16(11): e0259587, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34731213

RESUMEN

Sea lamprey (Petromyzon marinus), a parasitic fish which survives on blood of other fishes, is consumed as a delicacy in many countries. Our earlier studies on sea lamprey compounds that showed potential to deter adult sea lampreys yielded several sterols, glycerides, free fatty acids, amino acids, organic acids and nitrogenous compounds. Therefore, this study was to assess the health-benefits of these compounds including additional isolates from HPLC fractions that kept aside due to lack of activity in sea lamprey deterrent assays. In vitro cyclooxygenase enzymes (COX-1 and -2) and lipid peroxidation (LPO) inhibitory assays, respectively, were used to determine antiinflammatory and antioxidant activities. Among the tested sterols, cholesteryl eicosapentaenoate and cholesteryl arachidonate exhibited IC50 values of 14.6 and 17.7 µg/mL for COX-1 and 17.3 and 20.8 µg/mL for COX-2, respectively. Cholesteryl palmitate and cholesteryl oleate showed moderate COX-1 and COX-2 enzyme inhibition at 25 µg/mL. Amino acids arginine, tyrosine, glutamic acid, tryptophan and asparagine also showed moderate COX-1 and COX-2 inhibition at the same concentration. Among the twelve new isolates from fractions that we did not investigate earlier, a novel uracil derivative petromyzonacil showed COX-1 and COX-2 inhibition at 25 µg/mL by 35 and 15%, respectively. Cholesterol esters tested at 25 µg/mL exhibited LPO inhibition between 38 and 82 percent. Amino acids cysteine, methionine, aspartic acid, threonine, tryptophan, histidine, glutamic acid, phenylalanine and tyrosine at 25 µg/mL showed LPO inhibition between 37 and 58% and petromyzonacil by 32%. These assay results indicate that consumption of sea lamprey offer health-benefits in addition to nutritional benefits.


Asunto(s)
Petromyzon/metabolismo , Animales , Antiinflamatorios/farmacología , Antioxidantes/metabolismo , Bioensayo , Ciclooxigenasa 1/metabolismo , Ciclooxigenasa 2/metabolismo , Peroxidación de Lípido/efectos de los fármacos
6.
Int J Med Mushrooms ; 23(9): 73-83, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34591400

RESUMEN

Species of genus Morchella are high-value edible mushrooms. They are sought after by culinary experts due to their aroma, flavor, meaty texture, and health benefits. M. rufobrunnea, M. sextelata, and M. americana were chosen in this study and investigated for their medicinal quality by using in vitro anti-inflammatory and antioxidant assays. This sampling represents conditions by which morels are produced (cultivated indoors, cultivated outdoors, and collected from natural habitats, respectively) for commercial markets. Both aqueous and methanolic extracts of all three morel species showed identical chromatographic and bioassay profiles, independent of their phylogenetic position or production method. In an antioxidant assay, aqueous and methanolic extracts of these mushrooms at 100 µg/mL inhibited lipid peroxidation (LPO) by 59%-62% and 33%-36%, respectively. In an anti-inflammatory assay using cyclooxygenase enzymes (COX-1 and COX-2), aqueous and methanolic extracts at 100 µg/mL showed COX-1 enzyme inhibition by 53%-57% and 30%-32% and COX-2 enzyme inhibition by 38%-44% and 16%-17%, respectively. Chromatographic purification and spectroscopic characterization of M. rufobrunnea extracts afforded five sugars (compounds 1-5), seven organic acids (compounds 6-13), three flavonoids (compounds 14-16), triglycerides, free fatty acids, and three sterols (compounds 17-19). This is the first report of COX-1 and COX-2 enzymes and LPO inhibitory activities of pure isolates (S)-morelid (compound 6), glutamic acid (compound 9), and brassicasterol (compound 19). This study also showed inhibitions of COX-1 (by 84%, 33%, and 37%), COX-2 (by 47%, 11%, and 22%), and LPO (by 74%, 48%, and 35%), respectively, at 25 µg/mL.


Asunto(s)
Agaricus , Ascomicetos , Antiinflamatorios/farmacología , Antioxidantes/farmacología , Filogenia
7.
PLoS One ; 14(5): e0217417, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31120997

RESUMEN

The sea lamprey (Petromzons marinus) is a devastating invasive species that represents a significant impediment to restoration of the Laurentian Great Lakes. There is substantial interest in developing environmentally benign control strategies for sea lamprey, and many other aquatic invasive species, that employ the manipulation of semiochemical information (pheromones and chemical cues) to guide the movements of invaders into control opportunities (e.g. traps, locations for safe pesticide application, etc.). A necessary precursor to the use of semiochemicals in conservation activities is the identification of the chemical constituents that compose the odors. Here, we characterize the major nitrogenous substances from the water-soluble fraction of a skin extract that contains the sea lamprey alarm cue, a powerful repellent that has proven effective in guiding the movements of migrating sea lamprey in rivers. Nitrogenous compounds are suspected components of fish alarm cues as the olfactory sensory neurons that mediate alarm responses transduce amino acids and related compounds. A laboratory assay confirmed the behavioral activity contained in the alarm cue resides in the water-soluble fraction of the skin extract. This water-soluble fraction consisted primarily of creatine (70%), heterocyclic nitrogenous compounds (4.3%) and free amino acids (18.4%), respectively. Among the free amino acids characterized in our study, essential amino acids constituted 13% of the water-soluble fraction. Free amino acids isolated from the water-soluble fraction composed of arginine, phenylalanine, threonine, and asparagine 3.9, 2.7, 2.6 and 2.4% of the water-soluble fraction, respectively. We discuss the implications of these findings for understanding the nature and use of the sea lamprey alarm cue in conservation activities.


Asunto(s)
Compuestos de Nitrógeno/análisis , Petromyzon/fisiología , Migración Animal , Animales , Femenino , Great Lakes Region , Especies Introducidas , Masculino , Compuestos de Nitrógeno/metabolismo , Piel/química , Piel/metabolismo
8.
J Nat Prod ; 80(9): 2472-2477, 2017 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-28885836

RESUMEN

Purification of extracts from Prangos haussknechtii Bioss afforded prenylated coumarins 1 and 2, monoterpenoid 3, amino acid derivative 4, and seven known compounds. Spectroscopic methods permitted establishment of the structures and relative configuration of these compounds. The pure isolates were tested for antioxidant and anti-inflammatory activities using lipid peroxidation (LPO), 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide (MTT), and cyclooxygenase (COX-1 and -2) enzyme inhibitory assays. Compounds 1-4 inhibited LPO with IC50 values between 43 and 114 µM and reduced MTT to formazan blue between 48 and 128 µM. In anti-inflammatory assays using cyclooxygenase enzymes, COX-1 and -2, these compounds showed inhibition, with IC50 values ranging from 34 to 56 µM.


Asunto(s)
Antioxidantes/farmacología , Cumarinas/aislamiento & purificación , Cumarinas/farmacología , Inhibidores de la Ciclooxigenasa/aislamiento & purificación , Inhibidores de la Ciclooxigenasa/farmacología , Extractos Vegetales/química , Tetrazoles/aislamiento & purificación , Tetrazoles/farmacología , Tiazoles/aislamiento & purificación , Tiazoles/farmacología , Antiinflamatorios/farmacología , Antioxidantes/química , Cumarinas/química , Inhibidores de la Ciclooxigenasa/química , Peroxidación de Lípido , Estructura Molecular , Tetrazoles/química , Sales de Tetrazolio , Tiazoles/química
9.
PLoS One ; 11(12): e0168609, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27992570

RESUMEN

The sea lamprey (Petromzons marinus) is an invasive ectoparasite of large-bodied fishes that adversely affects the fishing industry and ecology of the Laurentian Great Lakes. Lipid content in the whole sea lamprey and muscles, liver and kidney of metamorphosing larval stages has been reported. Similarly, the fatty acid profile of the rope tissues of sexually-mature male sea lampreys has also been reported. The average body weight of a sub-adult migratory sea lamprey is 250 g, which includes 14.4% skin (36 g). Our preliminary extraction data of an adult sea lamprey skin revealed that it contained approximately 8.5% of lipophilic compounds. Lamprey skin is home to a naturally aversive compound (an alarm cue) that is being developed into a repellent for use in pest management. As part of an ongoing investigation to identify the chemical structure of the sea lamprey alarm cue, we extracted the skin with water and methanol, respectively. The methanolic extract (1.55%) contained exclusively lipophilic compounds and did not include the alarm cue. We chemically characterized all compounds present in the methanolic extract as cholesterol esters (CE), tri- and di-glycerides (TG and DG), cholesterol, free fatty acids (FFA) and minor amounts of plasticizers. The free fatty acids fraction was composed of saturated (41.8%), monounsaturated (40.7%) and polyunsaturated (17.4%) fatty acids, respectively. The plasticizers characterized were phthalate and benzoate and found to be 0.95 mg and 2.54 mg, respectively, per adult sea lamprey skin. This is the first report of the chemical characterization of all the lipophilic constituents in the skin of sub-adult migratory sea lamprey. The CEs isolated and characterized from sea lamprey skin are also for the first time.


Asunto(s)
Ácidos Grasos/metabolismo , Especies Introducidas , Lampreas/metabolismo , Piel/metabolismo , Animales , Ácidos Grasos/química , Great Lakes Region , Masculino , Piel/química
10.
Nat Prod Commun ; 11(5): 579-82, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27319121

RESUMEN

Tanacetum huronense (Lake Huron tansy), which is native to the upper Midwest region of USA and Canada, was examined for the presence of anticancer compounds using an in vitro human tumor cell proliferation inhibition assay, with glioblastoma derived cell line U-87 MG. Bioassay-directed purification of the ethyl acetate extract of the aerial portion of this plant identified six active sesquiterpenoid lactones (1-6). Among these, compounds 5 and 6 are new structural analogs. One of the most abundant isolates, tanacin (4), exhibited the greatest inhibition with an IC50 value of 4.5 µg/mL.


Asunto(s)
Antineoplásicos Fitogénicos/aislamiento & purificación , Flavonoides/aislamiento & purificación , Glioblastoma/tratamiento farmacológico , Fitoterapia , Tanacetum/química , Antineoplásicos Fitogénicos/química , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Flavonoides/uso terapéutico , Humanos , Lactonas/química , Lactonas/aislamiento & purificación , Extractos Vegetales/uso terapéutico , Sesquiterpenos/química , Sesquiterpenos/aislamiento & purificación
11.
Bioorg Med Chem ; 24(11): 2441-50, 2016 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-27112450

RESUMEN

Screening of a library of diverse heterocyclic scaffolds identified substituted quinolines as inhibitors of the human proteasome. The heterocyclic library was prepared via a novel titanium-catalyzed multicomponent coupling reaction, which rendered a diverse set of isoxazoles, pyrimidines, pyrroles, pyrazoles and quinolines. SAR of the parent lead compound indicated that hydrophobic residues on the benzo-moiety significantly improved potency. Lead compound 25 inhibits the chymotryptic-like proteolytic activity of the proteasome (IC50 5.4µM), representing a new class of nonpeptidic, noncovalent proteasome inhibitors.


Asunto(s)
Complejo de la Endopetidasa Proteasomal/metabolismo , Inhibidores de Proteasoma/farmacología , Quinolinas/farmacología , Relación Dosis-Respuesta a Droga , Células HeLa , Humanos , Estructura Molecular , Inhibidores de Proteasoma/síntesis química , Inhibidores de Proteasoma/química , Quinolinas/síntesis química , Quinolinas/química , Relación Estructura-Actividad
12.
Nat Prod Commun ; 11(9): 1313-1316, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-30807032

RESUMEN

Chinese yam (Dioscorea opposita), peeled or whole, is a popular food item that is considered to be healthy. Often, the yam is peeled before cooking. However, it is also consumed with peel. Therefore, in this study, the peel of this yam was extracted sequentially with n-hexane, ethyl acetate and methanol, and studied for its health-benefits, using in vitro bioassays. Bioactivity-guided purifications of extracts of the peel afforded phenanthrenes (1-4), as characterized- by spectroscopic methods. Phenanthrene I is a novel analogue. The extracts and isolates were tested for antiinflammatory activity using cyclooxygenase enzyme (COX- I and -2) inhibitory assays. All phenanthrenes isolated from the yam peel showed higher inhibition of COX enzymes than the over-the-counter nonsteroidal anti-inflammatory drugs (NSAIDs) aspirin, ibuprofen and naproxen.


Asunto(s)
Antiinflamatorios/farmacología , Inhibidores de la Ciclooxigenasa/farmacología , Dioscorea/química , Fenantrenos/farmacología , Tubérculos de la Planta/química , Antiinflamatorios/aislamiento & purificación , China , Inhibidores de la Ciclooxigenasa/aislamiento & purificación , Estructura Molecular , Fenantrenos/aislamiento & purificación , Fitoquímicos/aislamiento & purificación , Fitoquímicos/farmacología , Extractos Vegetales/química
13.
Food Chem ; 167: 24-9, 2015 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-25148954

RESUMEN

Coriander leaves and seeds are widely used as a condiment and spice. The use of roasted coriander seeds in food and beverage is very common. In this study, we investigated raw and roasted coriander seeds for their functional food quality using antioxidant, anti-inflammatory and human tumour cell proliferation inhibitory assays. The hexane and methanolic extracts of raw and roasted coriander seeds showed identical chromatographic and bioassay profiles. Chromatographic purification of the roasted seed extracts afforded tripetroselinin as the predominant component. Other isolates were petroselinic acid, 1,3-dipetroselinin, 2-C-methyl-d-erythritol, 2-C-methyl-d-erythritol 4-O-ß-d-glucopyranoside and linalool. Hexane and methanolic extracts of both raw and roasted seeds and pure isolates from them showed comparable antioxidant and anti-inflammatory activities to the positive controls used in the assays, and inhibited the growth of human tumour cells AGS (gastric carcinoma), DU-145 and LNCaP (prostate carcinoma), HCT-116 (colon carcinoma), MCF-7 (breast carcinoma) and NCI-H460 (lung carcinoma) by 4-34%, respectively.


Asunto(s)
Antioxidantes/análisis , Bioensayo/métodos , Coriandrum/química , Alimentos Funcionales/análisis , Técnicas In Vitro/métodos , Monoterpenos/química , Extractos Vegetales/química , Especias/análisis , Monoterpenos Acíclicos , Antiinflamatorios/farmacología , Humanos , Masculino , Semillas/química
14.
Chem Commun (Camb) ; 48(3): 440-2, 2012 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-22083455

RESUMEN

A simple titanium complex catalyzes the coupling of alkynes, isonitriles, and monosubstituted hydrazines to generate substituted pyrazoles in a single step.


Asunto(s)
Complejos de Coordinación/química , Pirazoles/química , Titanio/química , Alquinos/química , Catálisis , Cristalografía por Rayos X , Hidrazinas/química , Conformación Molecular , Nitrilos/química , Pirazoles/síntesis química
15.
Langmuir ; 24(11): 5689-99, 2008 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-18452320

RESUMEN

Aqueous solutions of four cationic poly(propylenimine) low-generation dendrimers of different architecture and hydrophobicity have been examined as media for acid-base reactions of indicator dyes. The cationic dendrimers in solution can be considered as oligomers of cationic polyelectrolytes, or surfactant-like species, able to form micelles through self-association or sometimes even as unimolecular micelles. The dendrimers influence the ionization constants, tautomeric equilibria, and absorption/emission/excitation spectra of indicator dyes. The p K a values of the majority of the indicator dyes decrease in dendrimer solutions, often by 1-2 p K a units, similar to effects registered in micellar solutions of cationic surfactants. Analogously, the shifts of absorption band maxima indicate that the microenvironments of the dyes bound to the dendrimers are less polar than in water. However, some spectral effects denote the specificity of the dendrimers. The greatest difference between the dendrimers and spherical surfactant micelles is revealed by kinetic processes, especially of bromophenol blue alkaline fading in a dendrimer solution but not in a micellar surfactant solution. Within the dendrimer series, the most significant differences were observed for substances possessing n-dodecyl tails on the one hand and those without such hydrophobic portions on the other. For the last-named, the decrease in p K a's of indicators, band shifts of their anions, and in particular displacement of tautomeric equilibria compared with aqueous solutions are much smaller than for more hydrophobic dendrimers.

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