Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
1.
Front Pharmacol ; 12: 669701, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34326768

RESUMEN

Hypobaric hypoxia (HH) is a stressful condition, which is more common at high altitudes and can impair cognitive functions. Ginkgo biloba L. leaf extract (GBE) is widely used as herbal medicine against different disorders. Its ability to improve cognitive functions, reduce oxidative stress, and promote cell survival makes it a putative therapeutic candidate against HH. The present study has been designed to explore the effect of GBE on HH-induced neurodegeneration and memory impairment as well as possible signaling mechanisms involved. 220-250 gm (approximately 6- to 8-week-old) Sprague Dawley rats were randomly divided into different groups. GBE was orally administered to respective groups at a dose of 100 mg/kg/day throughout the HH exposure, i.e., 14 days. Memory testing was performed followed by hippocampus isolation for further processing of different molecular and morphological parameters related to cognition. The results indicated that GBE ameliorates HH-induced memory impairment and oxidative damage and reduces apoptosis. Moreover, GBE modulates the activity of the small conductance calcium-activated potassium channels, which further reduces glutamate excitotoxicity and apoptosis. The exploration of the downstream signaling pathway demonstrated that GBE administration prevents HH-induced small conductance calcium-activated potassium channel activation, and that initiates pro-survival machinery by activating extracellular signal-regulated kinase (ERK)/calmodulin-dependent protein kinase II (CaMKII) and the cAMP response element-binding protein (CREB) signaling pathway. In summary, the current study demonstrates the beneficial effect of GBE on conditions like HH and provides various therapeutic targets involved in the mechanism of action of GBE-mediated neuroprotection.

2.
J Family Med Prim Care ; 8(10): 3230-3235, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31742147

RESUMEN

BACKGROUND: A multidisciplinary approach involving healthcare students for health promotion has been recommended. With this view, the primary phase of the integrated health promotion program (IHPP) was designed and pilot tested. METHODS: A pre-post-intervention study was conducted among 55 housewives of two self-help groups in India. The intervention consisted of a motivational interview, interactive session with a nutritionist, group discussion, personal hygiene training, and an illustrative reinforcement leaflet. Interventions were provided by trained dental students. The evaluation was based on outcomes from six tools specifically tailored for the program. These were the health self-regulation self-efficacy scale (HSSS), visual analogue scale (VAS) for self-health perception, oral health knowledge and attitude questionnaire, motivational interview, group discussion, and personal hygiene demonstration test. RESULTS: Statistically significant change in mean pre- and postprogram scores in HSSS (P < 0.001), its two components, metacognitive component, action component, as well as VAS (P = 0.001) indicated a change in health-related perceptions in the participants. Mean oral health knowledge score (6.1), as well as attitude score (3.8), was fair. Most of the participants were able to demonstrate personal hygiene and tooth brushing correctly; take collective decisions about their health, plan changes in their diet, and resolve upon bringing about healthy changes in their lifestyle. CONCLUSION: The program evaluation indicated successful intervention and may be replicated in a larger population. Healthcare student population may be used in developing countries to bring about an attitude change in the underprivileged population through an IHPP.

3.
Front Biosci (Elite Ed) ; 10(3): 469-480, 2018 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-29772520

RESUMEN

Oxidative stress is well known to be involved in pathophysiology of several disorders. Valeriana wallichii (VW) root extracts is known for its expedient activities but its antioxidant and cytoprotective efficacy need to be explored further. In present study tertiary-butyl hydroperoxide (tert-BOOH) was used to induce oxidative stress in C6 glioma cells. Antioxidant activity of the VW root extracts were evaluated by chemical assays i.e. DPPH, ABTS and FRAP assay. Further effect of VW on tert-BOOH induced oxidative stress and mitochondrial damage was studied. Result of present study revealed that exposure of cells to tert-BOOH resulted in increase in cytotoxicity, reactive oxygen species (ROS) production and decrease in mitochondrial membrane potential, super oxide dismutase, catalase, glutathione peroxidase and glutathione reductase. On the other hand, pretreatment of cells with VW extracts ameliorated these damaging effects. Additionally, HPLC analysis revealed hesperidin as an active ingredient and concentration of heavy metal was found within the maximum permissible limits prescribed by WHO. In conclusion present study revealed the antioxidant and cytoprotective property of VW against oxidative stress.


Asunto(s)
Antioxidantes/análisis , Extractos Vegetales/química , Valeriana/química , Animales , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Flavonoides/análisis , Fenoles/análisis , Ratas , terc-Butilhidroperóxido
4.
Adv Neurobiol ; 12: 307-21, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27651260

RESUMEN

Scenic view at high altitude is a pleasure to the eyes, but it has some shortcoming effects as well. High altitude can be divided into different categories, i.e., high altitude (3000-5000 ft), very high altitude (5000-8000 ft), and extreme altitude (above 8000 ft). Much of the population resides at high altitude, and others go there for tourism. Military personnel are also posted there to defend boundaries. As we ascent to high altitude, partial pressure of oxygen reduces, whereas concentration remains the same; this reduces the availability of oxygen to different body parts. This pathophysiological condition is known as hypobaric hypoxia (HH) which leads to oxidative stress and further causes cognitive dysfunction in some cases. Hypoxia causes neurodegeneration in different brain regions; however, the hippocampus is found to be more prone in comparison to other brain regions. As the hippocampus is affected most, therefore, spatial memory is impaired most during such condition. This chapter will give a brief review of the damaging effect of high altitude on cognition and also throw light on possible herbal interventions at high altitude, which can improve cognitive performance as well as provide protection against the deteriorating effect of hypobaric hypoxia at high altitude.


Asunto(s)
Altitud , Encéfalo/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/farmacología , Mal de Altura/prevención & control , Animales , Humanos , Hipoxia Encefálica/fisiopatología , Oxígeno/metabolismo , Ratas Sprague-Dawley
5.
ScientificWorldJournal ; 2014: 890151, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25506619

RESUMEN

Antinociceptive and anti-inflammatory potentials of methanolic extract of Bridelia retusa fruit (BRME) were evaluated against different animal models in rodents. Antinociceptive effects of BRME were assessed in mice using the acetic acid-induced writhing and formalin test. Anti-inflammatory effects of BRME in three different doses, namely, 100, 200, and 400 mg/kg, were evaluated by utilizing different animal models representing various changes associated with inflammation, namely, carrageenan-induced paw oedema, histamine and serotonin-induced paw oedema, arachidonic acid-induced paw oedema, formalin-induced paw oedema, TPA-induced ear oedema, acetic acid-induced vascular permeability, total WBC count in paw fluid, and myeloperoxidase assay. Also BRME was phytochemically evaluated using chromatographic method. The BRME did not exhibit any signs of toxicity up to a dose of 2000 mg/kg. The extract showed statistical significant inhibition of induced nociception and inflammation in dose dependent manner. The higher dose of extract significantly inhibited pain and inflammation against control (P < 0.001). HPLC results revealed the presence of gallic acid and ellagic acid as phytoconstituents in BRME and it was proven as anti-inflammatory agents. The present study scientifically demonstrated the antinociceptive and anti-inflammatory potential of fruit of B. retusa methanolic extract. These effects may be attributed to the presence of polyphenolic phytoconstituents in the extract.


Asunto(s)
Analgésicos/farmacología , Antiinflamatorios/farmacología , Euphorbiaceae/química , Frutas/química , Metanol/química , Extractos Vegetales/farmacología , Analgésicos/uso terapéutico , Animales , Antiinflamatorios/uso terapéutico , Permeabilidad Capilar/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Edema/sangre , Edema/tratamiento farmacológico , Ácido Elágico/análisis , Femenino , Ácido Gálico/análisis , Indometacina/farmacología , Indometacina/uso terapéutico , Recuento de Leucocitos , Masculino , Ratones , Extractos Vegetales/uso terapéutico , Ratas Wistar , Estándares de Referencia
6.
PLoS One ; 9(10): e105311, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25310001

RESUMEN

Withania somnifera root extract has been used traditionally in ayurvedic system of medicine as a memory enhancer. Present study explores the ameliorative effect of withanolide A, a major component of withania root extract and its molecular mechanism against hypoxia induced memory impairment. Withanolide A was administered to male Sprague Dawley rats before a period of 21 days pre-exposure and during 07 days of exposure to a simulated altitude of 25,000 ft. Glutathione level and glutathione dependent free radicals scavenging enzyme system, ATP, NADPH level, γ-glutamylcysteinyl ligase (GCLC) activity and oxidative stress markers were assessed in the hippocampus. Expression of apoptotic marker caspase 3 in hippocampus was investigated by immunohistochemistry. Transcriptional alteration and expression of GCLC and Nuclear factor (erythroid-derived 2)-related factor 2 (Nrf2) were investigated by real time PCR and immunoblotting respectively. Exposure to hypobaric hypoxia decreased reduced glutathione (GSH) level and impaired reduced gluatathione dependent free radical scavenging system in hippocampus resulting in elevated oxidative stress. Supplementation of withanolide A during hypoxic exposure increased GSH level, augmented GSH dependent free radicals scavenging system and decreased the number of caspase and hoescht positive cells in hippocampus. While withanolide A reversed hypoxia mediated neurodegeneration, administration of buthionine sulfoximine along with withanolide A blunted its neuroprotective effects. Exogenous administration of corticosterone suppressed Nrf2 and GCLC expression whereas inhibition of corticosterone synthesis upregulated Nrf2 as well as GCLC. Thus present study infers that withanolide A reduces neurodegeneration by restoring hypoxia induced glutathione depletion in hippocampus. Further, Withanolide A increases glutathione biosynthesis in neuronal cells by upregulating GCLC level through Nrf2 pathway in a corticosterone dependenet manner.


Asunto(s)
Glutatión/biosíntesis , Hipocampo/efectos de los fármacos , Hipoxia/metabolismo , Degeneración Nerviosa/tratamiento farmacológico , Fármacos Neuroprotectores/farmacología , Witanólidos/farmacología , Animales , Apoptosis/efectos de los fármacos , Caspasa 3/metabolismo , Corticosterona/farmacología , Radicales Libres/metabolismo , Glutamato-Cisteína Ligasa/genética , Glutamato-Cisteína Ligasa/metabolismo , Hipocampo/metabolismo , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Memoria/efectos de los fármacos , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Degeneración Nerviosa/etiología , Degeneración Nerviosa/metabolismo , Fármacos Neuroprotectores/uso terapéutico , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismo , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Receptores de Mineralocorticoides/genética , Receptores de Mineralocorticoides/metabolismo , Superóxido Dismutasa/metabolismo , Transcripción Genética/efectos de los fármacos , Witanólidos/uso terapéutico
7.
J Oral Sci ; 55(1): 9-15, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23485595

RESUMEN

This in vitro study evaluated the color stability, gloss, and surface roughness (Ra) of four indirect composites. Enamel and dentin shades of Radica, Sculpture Plus, Belleglass-NG, and Gradia Indirect were evaluated for color stability. Specimens were stored in a staining solution (coffee) and assessed every 3 days for a period of 21 days, after which color difference (∆E*) was calculated. Only enamel shades were used for measuring gloss and surface roughness at 0, 5000, 10,000, and 20,000 cycles of simulated toothbrushing. The results were statistically analyzed using repeated measures analysis of variance (ANOVA) and Tukey's test. Statistically significant changes in ∆E* during the 21-day period were observed in all indirect composites for enamel and dentin shades, and ∆E* was greater than the clinically acceptable value of 3.3. Belleglass-NG showed the least change in ∆E*, while Sculpture Plus had large changes in ∆E*. In all groups, gloss was 75% lower than baseline values after 10,000 cycles of toothbrushing. After 20,000 cycles, surface roughness was highest in Radica and lowest in Belleglass-NG. Belleglass-NG had higher color stability and gloss retention, and lower surface roughness, as compared with the other composite systems.


Asunto(s)
Resinas Compuestas/química , Materiales Dentales/química , Café , Color , Luces de Curación Dental/clasificación , Pulido Dental/métodos , Humanos , Luz , Ensayo de Materiales , Metacrilatos/química , Polimerizacion , Espectrofotometría , Propiedades de Superficie , Factores de Tiempo , Cepillado Dental , Pastas de Dientes/química
8.
J Ethnopharmacol ; 145(2): 431-41, 2013 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-23211660

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Withania somnifera (WS) root extract has been used traditionally in ayurvedic system of medicine as a memory enhancer and anti-stress agent. AIM OF THE STUDY: To evaluate the neuroprotective and prophylactic potential of WS root extract in ameliorating hypobaric hypoxia (HH) induced memory impairment and to explore the underlying molecular mechanism. MATERIALS AND METHODS: WS root extract was administered to male Sprague Dawley rats during a period of 21 days pre-exposure and 07 days exposure to a simulated altitude of 25,000 ft. Spatial memory was assessed by Morris Water Maze. Neurodegeneration, corticosterone, acetylcholine (Ach) levels, acetylcholine esterase (AchE) activity, oxidative stress markers and nitric oxide (NO) concentration were assessed in the hippocampus. Synaptic and apoptotic markers were also investigated by immunoblotting. To study the role of NO in regulating corticosterone mediated signaling, the neuronal nitric oxide synthase (n-NOS) inhibitor, L-Nitro-arginine methyl ester (L-Name) and NO agonist sodium nitroprusside (SNP) were administered from 3rd to 7th day of hypoxic exposure. RESULTS: Administration of WS root extract prevented HH induced memory impairment and neurodegeneration along with decreased NO, corticosterone, oxidative stress and AchE activity in hippocampal region. Inhibition of NO synthesis by administration of L-Name reduced corticosterone levels in hippocampus during hypoxic exposure while co-administration of corticosterone increased neurodegeneration. Administration of sodium nitroprusside (SNP) along with WS root extract supplementation during hypoxic exposure increased corticosterone levels and increased the number of pyknotic cells. CONCLUSION: WS root extract ameliorated HH induced memory impairment and neurodegeneration in hippocampus through NO mediated modulation of corticosterone levels.


Asunto(s)
Trastornos de la Memoria/tratamiento farmacológico , Fármacos Neuroprotectores/uso terapéutico , Fitoterapia , Extractos Vegetales/uso terapéutico , Withania , Acetilcolina/metabolismo , Acetilcolinesterasa/metabolismo , Animales , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Canales de Calcio Tipo L/metabolismo , Corticosterona/metabolismo , Glutatión/metabolismo , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Hipoxia/complicaciones , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Trastornos de la Memoria/etiología , Trastornos de la Memoria/metabolismo , Moléculas de Adhesión de Célula Nerviosa/metabolismo , Fármacos Neuroprotectores/farmacología , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo I/metabolismo , Extractos Vegetales/farmacología , Raíces de Plantas , Ratas , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismo , Superóxido Dismutasa/metabolismo , Sinaptofisina/metabolismo
9.
Artículo en Inglés | MEDLINE | ID: mdl-22919408

RESUMEN

Present study was aimed to isolate and evaluate the antidiabetic activity of phytoconstituents from fruit rinds of Punica granatum. With the above objectives Valoneic acid dilactone (VAD) was isolated from methanolic fruit rind extracts of Punica granatum (MEPG) and confirmed by (1)H-NMR, (13)C-NMR, and mass spectral data. Antidiabetic activity was evaluated by Aldose reductase, α-amylase and PTP1B inhibition assays in in vitro and Alloxan-induced diabetes in rats was used as an in vivo model. In bioactivity studies, MEPG and VAD have showed potent antidiabetic activity in α-amylase, aldose reductase, and PTP1B inhibition assays with IC(50) values of 1.02, 2.050, 26.25 µg/mL and 0.284, 0.788, 12.41 µg/mL, respectively. Furthermore, in alloxan-induced diabetes model MEPG (200 and 400 mg/kg, p.o.) and VAD (10, 25, and 50 mg/kg, p.o.) have showed significant and dose dependent antidiabetic activity by maintaining the blood glucose levels within the normal limits. Inline with the biochemical findings histopathology of MEPG (200 and 400 mg/kg, p.o.), VAD (10, 25, and 50 mg/kg, p.o.), and glibenclamide (10 mg/kg, p.o.) treated animals showed significant protection against alloxan-induced pancreatic tissue damage. These findings suggest that MEPG and VAD possess significant antidiabetic activity in both in vitro and in vivo models.

10.
Lipids ; 46(10): 961-8, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21739242

RESUMEN

Conjugated linoleic acid (CLA) is a collection of octadecadienoic fatty acids that have been shown to possess numerous health benefits. The CLA used in our study was produced by the photoisomerization of soybean oil and consists of about 20% CLA; this CLA consists of 75% trans-trans (a mixture of t8,t10; t9,t11; t10,t12) isomers. This method could be readily used to increase the CLA content of all soybean oil used as a food ingredient. The objective of this study was to determine the effects of trans-trans CLA-rich soy oil, fed as a dietary supplement, on body composition, dyslipidemia, hepatic steatosis, and markers of glucose control and liver function of obese fa/fa Zucker rats. The trans-trans CLA-rich soy oil lowered the serum cholesterol and low density lipoprotein-cholesterol levels by 41 and 50%, respectively, when compared to obese controls. Trans-trans CLA-rich soy oil supplementation also lowered the liver lipid content significantly (P < 0.05) with a concomitant decrease in the liver weight in the obese rats. In addition, glycated hemoglobin values were improved in the group receiving CLA-enriched soybean oil in comparison to the obese control. PPAR-γ expression in white adipose tissue was unchanged. In conclusion, trans-trans CLA-rich soy oil was effective in lowering total liver lipids and serum cholesterol.


Asunto(s)
Colesterol/sangre , Hígado Graso/dietoterapia , Ácidos Linoleicos Conjugados/uso terapéutico , Obesidad/dietoterapia , Aceite de Soja/uso terapéutico , Tejido Adiposo/metabolismo , Animales , Glucemia , Peso Corporal , Ingestión de Alimentos , Hígado Graso/complicaciones , Femenino , Expresión Génica , Ácidos Linoleicos Conjugados/química , Lípidos/sangre , Hígado/química , Obesidad/complicaciones , PPAR gamma/genética , Ratas , Ratas Zucker , Aceite de Soja/química
11.
J Agric Food Chem ; 58(5): 2952-7, 2010 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-20136082

RESUMEN

Conjugated linoleic acid (CLA) is found in small quantities in dairy and beef products. Obtaining optimum dietary CLA levels from these sources requires an increased intake of saturated fat. A 20% CLA soy oil was produced by UV photoisomerization of soy oil linoleic acid (LA), which is naturally low in saturated fat, but no other high-LA vegetable oils have been studied for their potential as CLA-rich oils. The objectives of this research were to (1) compare flax, sunflower, corn, soy, and high-LA safflower oils as sources of CLA-rich vegetable oils using laboratory-scale equipment, (2) compare CLA yields obtained by laboratory-scale and pilot-scale equipment, and (3) compare the oxidative stabilities of laboratory-scale processed oils. High-LA safflower oil produced the most CLA; soy oil produced slightly less, followed by corn, with flax producing very little and sunflower none at all. Minor oil components and turbidity reduced CLA yields, suggesting that oils should be highly refined before CLA production. The pilot-scale system was more effective than the laboratory-scale system due to greater light exposure and larger surface area to volume ratio of the oil samples. The oxidative stabilities of high-LA safflower oil and soy oil were similar before or after irradiation, indicating that these oils are the most suitable for high-CLA production.


Asunto(s)
Ácido Linoleico/química , Aceites de Plantas/química , Isomerismo , Fotoquímica , Proyectos Piloto
12.
J Agric Food Chem ; 57(22): 10483-8, 2009 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-19860450

RESUMEN

Conjugated linoleic acid (CLA) isomers in oils are currently measured as fatty acid methyl esters by a gas chromatography-flame ionization detector (GC-FID) technique, which requires approximately 2 h to complete the analysis. Hence, we aim to develop a method to rapidly determine CLA isomers in CLA-rich soy oil. Soy oil with 0.38-25.11% total CLA was obtained by photo-isomerization of 96 soy oil samples for 24 h. A sample was withdrawn at 30 min intervals with repeated processing using a second batch of oil. Six replicates of GC-FID fatty acid analysis were conducted for each oil sample. The oil samples were scanned using attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), and the spectrum was collected. Calibration models were developed using partial least-squares (PLS-1) regression using Unscrambler software. Models were validated using a full cross-validation technique and tested using samples that were not included in the calibration sample set. Measured and predicted total CLA, trans,trans CLA isomers, total mono trans CLA isomers, trans-10,cis-12 CLA, trans-9,cis-11 CLA and cis-10,trans-12 CLA, and cis-9,trans-11 CLA had cross-validated coefficients of determinations (R2v) of 0.97, 0.98, 0.97, 0.98, 0.97, and 0.99 and corresponding root-mean-square error of validation (RMSEV) of 1.14, 0.69, 0.27, 0.07, 0.14, and 0.07% CLA, respectively. The ATR-FTIR technique is a rapid and less expensive method for determining CLA isomers in linoleic acid photo-isomerized soy oil than GC-FID.


Asunto(s)
Ácidos Linoleicos Conjugados/análisis , Aceite de Soja/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Calibración , Isomerismo , Análisis de los Mínimos Cuadrados , Luz , Reproducibilidad de los Resultados
13.
J Agric Food Chem ; 57(19): 8989-97, 2009 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-19725543

RESUMEN

Conjugated linoleic acid (CLA) is produced by photoisomerization of soy oil linoleic acid. Yields increase with the degree of oil refining, but the effect of specific minor oil components is not known. Therefore, the objectives were to determine the effect of each soy oil minor component on CLA yields and oxidative stability after processing, to determine the effect of soy oil minor constituent interactions on CLA yields and oxidative stability, and to determine how soy oil Magnesol adsorption pretreatment affects CLA yields. Soy oils with varying levels of peroxides, tocopherols, phospholipids, free fatty acids (FFA), and lutein were each UV irradiated, and the CLA content and oxidative stability were determined. A peroxide value of above 0.8 greatly decreased CLA yields, as did phospholipids above 500 ppm. Tocopherols enhanced CLA production at low levels and reduced yields at high concentrations, while lutein and FFA had little effect. High CLA yields corresponded with a lower oil oxidative stability. The interactions between the minor components showed similar trends as seen in the single component study. These findings were supported by observations that Magnesol adsorption removed large quantities of phospholipids and peroxides from soy oil and greatly increased CLA yields but reduced the oxidative stability. Minor components, particularly peroxides and phospholipids, need to be removed from the oil to optimize CLA yields.


Asunto(s)
Ácidos Linoleicos Conjugados/síntesis química , Aceite de Soja/análisis , Aceite de Soja/química , Adsorción , Estabilidad de Medicamentos , Ácidos Grasos no Esterificados/análisis , Luteína/análisis , Oxidación-Reducción , Peróxidos/análisis , Fosfolípidos/análisis , Tocoferoles/análisis , Rayos Ultravioleta
14.
J Agric Food Chem ; 57(5): 1727-34, 2009 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-19216566

RESUMEN

Conjugated linoleic acid (CLA)-rich soy oil has been produced by soy oil linoleic acid (LA) photoisomerization, but CLA-rich oil triacylglycerol (TAG) characterization was not described. Therefore, the objectives were to identify and quantify new TAG fractions in CLA-rich oil by nonaqueous reversed-phase high-performance liquid chromatography (NARP-HPLC). Analytical NARP-HPLC with an acetonitrile/dichloromethane (ACN/DCM) gradient and an evaporating light scattering detector/ultraviolet (ELSD/UV) detector was used. New TAG peaks from LA-containing TAGs were observed. The LnLL, LLL, LLO, and LLP (Ln, linolenic; L, linoleic; O, oleic; and P, palmitic) peaks reduced after isomerization with an increase in adjacent peaks that coeluted with LnLnO, LnLO, LnOO, and LnPP. The newly formed peaks were wider than those of the original oil and absorbed at 233 nm, suggesting the possibility of various CLA containing TAGs. The HPLC profile showed five fractions of mixed TAGs, and fatty acid analysis showed that CLA isomers were found predominately in fractions 2 and 3, which originally contained most LA. The CLA isomers were 70-80% trans,trans and 20-30% cis,trans and trans,cis.


Asunto(s)
Ácidos Linoleicos Conjugados/análisis , Aceite de Soja/análisis , Triglicéridos/análisis , Cromatografía Líquida de Alta Presión
15.
J Agric Food Chem ; 56(17): 8174-8, 2008 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-18681439

RESUMEN

Photoirradiation processing can be used to rapidly synthesize conjugated linoleic acid (CLA) in large quantities in soy oil. The objective of this study was to evaluate the effect of the level of refining of soy oil on CLA yields and oxidative properties after photoirradiation. Crude, alkali-refined, alkali-refined bleached, and alkali-refined bleached and deodorized (RBD) soy oils were photoirradiated in a pilot-plant processing system for 12 h with 0.35% iodine catalyst at 47 degrees C. RBD soy oil gave the highest total CLA yield of 16.3% of total oil with 4.3% cis, trans- and trans, cis-CLA isomers. Oxidative stability as measured by weight gain during incubation at 64 degrees C showed that iodine decreased the induction time of soy oil samples by 2-4 days. Photoirradiation processing further decreased the induction time by 2 days as a result of loss of total tocopherols. Iodine addition increased the titratable acidity in all the samples of soy oil. However, the level of refining affects this increase of titratable acidity, and RBD soy oil was found to be the most stable. The study indicates that RBD soy oil was the most suitable candidate for photoirradiation processing. Thus, soy oil should be alkali-refined, bleached, deodorized, and then photoprocessed followed by a secondary adsorption step to remove the iodine catalyst to obtain a RBD CLA-rich soy oil.


Asunto(s)
Manipulación de Alimentos/métodos , Ácidos Linoleicos Conjugados/análisis , Aceite de Soja/química , Concentración de Iones de Hidrógeno , Yodo , Luz , Ácidos Linoleicos Conjugados/química , Oxidación-Reducción
16.
J Food Sci ; 72(1): S075-8, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17995902

RESUMEN

Conjugated linoleic acid (CLA) is found primarily in diary and beef products, but the health benefits of CLA can only be realized if they are consumed at much greater levels than a normal healthy dietary intake. We have recently shown that a CLA-rich soy oil can be produced by simple isomerization of linoleic acid in soy oil by photoirradiation. This oil may allow greatly increased dietary CLA without significantly elevating fat intake. The objective of this study was to prepare CLA-rich potato chips by frying in CLA-rich soy oil. Soy oil was photoisomerized in the presence of iodine catalyst with UV/visible light. The irradiated oil was clay processed to remove the residual iodine and this oil was then used to fry potato chips. Oil was extracted from fried chips and analyzed for its CLA content with gas chromatography. A 1-oz serving of CLA-rich potato chips contained approximately 2.4 g CLA as compared to 0.1 g CLA in 3-oz serving of steak fillet and 0.06 g CLA in 8-oz serving of whole milk. The peroxide value of the oil extracted from potato chips was found to be 1 meq/1000 g sample, which was within the acceptable commercial standards. This study may lead to the commercialization of CLA-rich food products.


Asunto(s)
Culinaria/métodos , Tecnología de Alimentos , Ácidos Linoleicos Conjugados/análisis , Fotoquímica , Solanum tuberosum/química , Aceite de Soja/química , Cromatografía de Gases , Alimentos Orgánicos , Humanos , Ácidos Linoleicos Conjugados/química
17.
J Agric Food Chem ; 55(3): 889-94, 2007 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-17263490

RESUMEN

Photoirradiation of soy oil with UV/visible light has been shown to produce significant amounts of trans,trans conjugated linoleic acid (CLA) isomers through conversion of various synthesized intermediate cis,trans isomers. The objective of this study was to determine the kinetics of CLA isomers synthesis to better understand the production of various isomers. Soy oil was irradiated with UV/visible light for 144 h in the presence of an iodine catalyst and CLA isomers analyzed by gas chromatography (GC). Arrhenius plots were developed for the conversion of soy oil linoleic acid (A) to form cis-, trans/trans-, cis-CLA (B), conversion of cis-, trans/trans-, cis-CLA to form trans,trans-CLA (C) with respect to B, and formation of trans,trans-CLA isomers with respect to C. The kinetics of consumption of linoleic acid (LA) to form cis-, trans/trans-, cis-CLA was found to be of second-order with a rate constant of 9.01 x 10-7 L/mol s. The rate of formation of cis-, trans/trans-, cis-CLA isomers depends on the rate of formation from LA and its rate of consumption to form trans,trans-CLA isomers. The conversion of cis-, trans/trans-, cis-CLA isomers to trans,trans-CLA isomers was found to be of first-order with a rate constant of 2.75 x 10-6 s-1. However, the formation of thermodynamically stable trans,trans-CLA isomers (C) with respect to C was found to be a zero-order reaction with a rate constant of 10.66 x 10-7 mol/L s. The consumption of LA was found to be the rate-determining step in the CLA isomers formation reaction mechanism. The findings provide a better understanding of the mechanism of CLA isomers synthesis by photoirradiation and the factors controlling the ratio of various isomers.


Asunto(s)
Ácidos Linoleicos Conjugados/química , Aceite de Soja/química , Isomerismo , Cinética , Fotoquímica , Aceite de Soja/efectos de la radiación , Termodinámica , Rayos Ultravioleta
18.
J Agric Food Chem ; 54(15): 5590-6, 2006 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-16848550

RESUMEN

Daily intake of conjugated linoleic acid (CLA), an anticarcinogenic, antiatherosclerotic, antimutagenic agent, and antioxidant, from dairy and meat products is substantially less than estimated required values. The objective of this study was to obtain CLA-rich soybean oil by a customized photochemical reaction system with an iodine catalyst and evaluate the effect of processing on iodine and iodo compounds after adsorption. After 144 h of irradiation, a total CLA yield of 24% (w/w) total oil was obtained with 0.15% (w/w) iodine. Trans,trans isomers (17.5%) formed the majority of the total yield and are also associated with health benefits. The isomers cis-9,trans-11 and trans-10,cis-12 CLA, associated with maximum health benefits, formed approximately 3.5% of the total oil. This amount is quite significant considering that total CLA obtained from dairy sources is only 0.6%. ATR-FTIR, 1H NMR, and GC-MS analyses indicated the absence of peroxide and aldehyde protons, providing evidence that secondary lipid oxidation products were not formed during the photochemical reaction. Adsorption processing vastly reduced the iodine and iodocompounds without CLA loss. Photocatalysis significantly increased the levels of CLA in soybean oil.


Asunto(s)
Ácidos Linoleicos Conjugados/análisis , Fotoquímica/instrumentación , Aceite de Soja/química , Catálisis , Cromatografía de Gases y Espectrometría de Masas , Yodo/análisis , Yodo/química , Cinética , Ácidos Linoleicos Conjugados/síntesis química , Espectroscopía de Resonancia Magnética , Espectroscopía Infrarroja por Transformada de Fourier
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA