This study investigated the effects of cooking treatments (boiling and steaming) and season of th... more This study investigated the effects of cooking treatments (boiling and steaming) and season of the year (spring and fall) on vitamin C content, total phenolics content (TPC), total flavonoids content (TFC), antioxidant activity and scavenging of nitric oxide (NO•), and superoxide radical (O 2-). After cooking, a significant decrease in vitamin C was observed (50 and 48.8% for boiling and 21 and 27.9% for steaming in spring and fall, respectively). TPC and TFC increased during steaming from 145-1480 mg GAE/kg and 348.6-797.2 mg QE/kg, respectively. DPPH values ranged from 2806-3801 μmol TE/kg and was affected by season whereas ORAC ranged from 1231.3-36,167.2 μmol TE/kg and was affected by cooking. The ability to scavenge NO• and O 2-, were not affected by neither cooking nor season. However, the inhibition of O 2 was higher for quintonil steamed in spring.
INTRODUCTION Medium chain fatty acids MCFAs are recognized for their health benefits. They are us... more INTRODUCTION Medium chain fatty acids MCFAs are recognized for their health benefits. They are used in enteral and parenteral nutrition for a series of medical conditions of patients suffering low absorption of fats, poor digestion, and metabolic difficulties related to cystic fibrosis, Crohn s disease, colitis and enteritis 1, 2. MCFAs with 6 to 14 carbons are of high interest for green chemistry due to their lathering and low-viscosity properties. They are widely used in detergents and lubricants. After esterification with alcohol, they can also be used as emulsifiers for foods and cosmetics, solvents for flavours, surface treatment of food products and as well as readily digestible fat in high-energy diets 3. In lipid research, thin layer chromatography TLC is commonly used for a rapid lipid fractionation and fatty acids profile characterizations. Nowadays, TLC constitutes a basic tool for modern analytical chemistry because of its
To study microwave heating for potential postharvest treatments against anthracnose disease, Coll... more To study microwave heating for potential postharvest treatments against anthracnose disease, Colletotrichum gloeosporioides growth–no-growth response after selected microwave treatments (2,450 MHz) was fitted by using a logistic regression model. Evaluated variables were power level, exposure time, presence or absence of water in the medium during treatment, and incubation-observation time. Depending on the setting, the applied power ranged from 77.2 to 435.6 W. For the experiments on dry medium (mold spores over filter paper), exposure times were 1, 2, 3, or 4 min, whereas spores dispersed in potato dextrose agar, a wet medium, had exposure times of 3, 6, or 9 s. Growth (response = 1) or no growth (response = 0) was observed after two different incubation-observation times (4 or 10 days). As expected, high power levels and long exposure times resulted in complete inhibition of C. gloeosporioides spore germination. In a number of cases (such as low power levels and short treatment t...
Milk-derived bioactive peptides with a single activity (e.g., antioxidant, immunomodulatory, or a... more Milk-derived bioactive peptides with a single activity (e.g., antioxidant, immunomodulatory, or antimicrobial) have been previously well documented; however, few studies describe multifunctional bioactive peptides, which may be preferred over single-activity peptides, as they can simultaneously trigger, modulate, or inhibit multiple physiological pathways. Hence, the aim of this study was to assess the anti-inflammatory, antihemolytic, antioxidant, antimutagenic, and antimicrobial activities of crude extracts (CE) and peptide fractions (<3 and 3-10 kDa) obtained from fermented milks with specific Lactobacillus plantarum strains. Overall, CE showed higher activity than both peptide fractions (<3 and 3-10 kDa) in most of the activities assessed. Furthermore, activity of <3 kDa was generally higher, or at least equal, to the 3 to 10 kDa peptide fractions. In particular, L. plantarum 55 crude extract or their fractions showed the higher anti-inflammatory (723.68-1,759.43 μg/mL of diclofenac sodium equivalents), antihemolytic (36.65-74.45% of inhibition), and antioxidant activity [282.8-362.3 μmol of Trolox (Sigma-Aldrich, St. Louis, MO) equivalents]. These results provide valuable evidence of multifunctional role of peptides derived of fermented milk by the action of specific L. plantarum strains. Thus, they may be considered for the development of biotechnological products to be used to reduce the risk of disease or to enhance a certain physiological function.
This study was aimed to prepare and characterize capsules loaded with Lacticaseibacillus rhamnosu... more This study was aimed to prepare and characterize capsules loaded with Lacticaseibacillus rhamnosus GG (LGG), evaluating cell viability under gastrointestinal in vitro conditions and during storage in yogurt and apple juice, an alternative to traditional probiotic foods for people who are lactose intolerant. The capsules were prepared by ionic gelation, with an emulsification process as pretreatment. Cell viability of encapsulated LGG was evaluated after two different homogenization processes: magnetic stirring (AM) and Ultraturrax® homogenizer (UT). The system with the best relationship between viability and morphology was UT, which produced a viability of 85.80%. During in vitro evaluation, the capsules provided higher protection than free cells, up to 100% of cell viability. The morphology of capsules of both systems displayed a continuous and homogeneous surface. The cell viability of the encapsulated probiotics added in apple juice stored for 22 days at 4 °C was 86.16% for AM an...
Haden mango slices (non-osmotic dehydrated, NOD) were immersed in calcium chloride (2 g/l), citri... more Haden mango slices (non-osmotic dehydrated, NOD) were immersed in calcium chloride (2 g/l), citric acid (5 g/l), hydrogen peroxide (25 ml/l) and sodium benzoate (20 g/l) solutions. Slices to be treated with osmotic dehydration (OD) were first immersed in calcium, then placed in the osmotic solution (sucrose 65 • Bx, 30 • C) and 211 mbar vacuum was applied for 30 min. After the osmotic treatment, the slices were immersed in the same solutions as for NOD slices. All the slices were stored in sterile chambers at 24, 13 or 5 • C. Both OD and NOD slices displayed sucrose synthesis (SS) during storage, which was highest in NOD slices that were kept at 13 • C. Sucrose synthesis was the most significant change during ripening of whole mangoes (WM). Starch breakdown could not supply the necessary substrates for sucrose synthesis in either whole mangoes or slices. Injured tissues from mango slices sustained sucrose synthesis, which was highest at 13 • C in NOD slices, but the osmotic treatment decreased sucrose formation. Storage at 5 • C for 12 days affected sucrose content of Haden mangoes. Glucose and fructose concentrations remained low in all treatments.
View related articles Citing articles: 3 View citing articles Conjugated linoleic acid content in... more View related articles Citing articles: 3 View citing articles Conjugated linoleic acid content in selected Mexican beef and dairy products Contenido de a´cido linoleico conjugado en carne de res y la´cteos Mexicanos seleccionados
The aims of this work were to estimate the content of acrylamide (AA) in food consumed by young p... more The aims of this work were to estimate the content of acrylamide (AA) in food consumed by young people in Mexico and calculate its intake in this population sector. Fifteen samples of heat-processed commercial foods, widely consumed in Mexico obtained from supermarkets and local convenience stores, and analyzed in triplicate to determine their concentration of acrylamide (µg/kg of product) by HPLC-UV and later assess the intake in young adults. Significantly high contents of acrylamide were found in most foods evaluated; the highest levels were found in fried products (5,914 µg/kg of product in potato chips). Based on food and portions that subjects reported, an intake of Acrylamide of 0.68 µg/kg bw/day was estimated. The estimated daily intake could be at levels above the limit established to avoid the risk of neurotoxicity. This research provides relevant information for public health experts, policy makers and consumers in general.
En este trabajo se utilizo una lipasa de Candida antarctica para la produccion de mono-, di- y tr... more En este trabajo se utilizo una lipasa de Candida antarctica para la produccion de mono-, di- y tri-acilgliceroles por esterificacion directa de acidos grasos poliinsaturados (AGPI) n-3 al glicerol. Se preparo un concentrado de AGPI n-3 (81,5% w/w) por hidrolisis quimica del aceite de sardina seguido de un tratamiento con urea. Las reacciones de esterificacion se realizaron colocando una proporcion de 2.62 mol AGPI n-3/mol glicerol en frascos de vidrio completamente sellados, agitados continuamente, manteniendo la temperatura constante (55°C). Las muestras se extrajeron a diferentes tiempos y se analizo el contenido de acilgliceroles por medio de HPLC-ELSD. Se desarrollo un modelo cinetico basado en un mecanismo de ping-pong multi-sustrato multi-producto para interpretar los datos experimentales. Se estimaron los parametros del modelo mediante regresion no-lineal sin restricciones en una plataforma MATLAB® (R2014a), con un coeficiente de determinacion (R 2 >0.9). El modelo obtenid...
Se han evaluado los cambios fisiologicos durante la maduracion de platanos pelados y sin pelar al... more Se han evaluado los cambios fisiologicos durante la maduracion de platanos pelados y sin pelar almacenados en camaras con atmosferas automodificadas. Se colocaron tres lotes de frutos en frascos de vidrio sellados y se mantuvieron a 20 ± 0,5o C. Se envasaron platanos enteros pelados y sin pelar dentro de frascos de vidrio y se dejaron sin envasar platanos enteros sin pelar como testigo. El pelado de los platanos verdes y firmes no ocasiono ningun tipo de deterioro ni interferencia en la maduracion normal cuando los platanos se mantuvieron dentro de las camaras de atmosferas automodificadas. La maduracion de los platanos pelados dentro de las atmosferas automodificadas fue similar al del testigo.
compendiou a reflexão renascentista sobre a arte de traduzir produzindo o ingente tratado Interpr... more compendiou a reflexão renascentista sobre a arte de traduzir produzindo o ingente tratado Interpretatio linguarum (Tradução de línguas), publicado em 1559. Dividido em três livros, com mais de 600 páginas, o tratado do teólogo puritano inglês, que, apesar de sua reconhecida importância, nunca foi reimpresso, nem recebeu edição crítica ou tradução integral a qualquer língua até hoje, é aqui apresentado em tradução ao português brasileiro. Abdicando de boa parte dos inúmeros exemplos oferecidos por Humphrey, selecionamos para esta publicação excertos do primeiro livro, o mais teórico de seu tratado, intitulado De ratione interpretandi (Da arte de traduzir).
Current changes in diet, characterized by an increase in the intake of sweetened beverages, are h... more Current changes in diet, characterized by an increase in the intake of sweetened beverages, are heavily related to metabolic disorders such as non-alcoholic fatty liver. This condition can produce simple steatosis and, in worse cases, potentially result in steatohepatitis, fibrosis, and cirrhosis, comparable to the damage caused by the consumption of more or less 20–30 g of alcohol per day. The main objective of this research was to evaluate the effect of curcumin (Curcuma longa) nanoemulsions, using mono- and diacylglycerides medium chain fatty acids as stabilizers in an in vivo hepatic steatosis rat model. Pathology was induced by providing 30% fructose intake in the drinking water. Globule sizes under 200 nm that were stable for 4 weeks were obtained; curcumin encapsulated in the nanoemulsion was >70%. The results revealed an improvement regarding body and liver weight in the animals treated with curcumin nanoemulsions. A decrease in total cholesterol, LDL, AST/ALT, and HDL in...
Structured phosphatidylcholine was successfully produced by acidolysis between phosphatidylcholin... more Structured phosphatidylcholine was successfully produced by acidolysis between phosphatidylcholine and free medium chain fatty acid, using phospholipase A1 immobilized on Duolite A568. Response surface methodology was applied to optimize the reaction system using three process parameters: molar ratio of substrates (phosphatidylcholine to free medium chain fatty acid), enzyme loading, and reaction temperature. All parameters evaluated showed linear and quadratic significant effects on the production of modified phosphatidylcholine; molar ratio of substrates contributed positively, but temperature influenced negatively. Increased enzyme loading also led to increased production of modified phosphatidylcholine but only during the first 9 hours of the acidolysis reaction. Optimal conditions obtained from the model were a ratio of phosphatidylcholine to free medium chain fatty acid of 1:15, an enzyme loading of 12%, and a temperature of 45°C. Under these conditions a production of modifie...
African Journal of Microbiology Research, Mar 5, 2013
Isothiocyanates (ITCs) is a group of defense related compounds synthesized by Brassicas that have... more Isothiocyanates (ITCs) is a group of defense related compounds synthesized by Brassicas that have positive effects on human health which suggest that they are environmentally friendly compounds to control fungi infections. However, the development of ITC-resistant strains of fungi is a matter of concern. The objective of the present work was to study the response of Alternaria alternata to allylisothiocyanate (AITC) and benzyl isothiocyanate (BITC) chronic exposure and the effect of the treatment on some of the inter simple sequence repeats (ISSR) regions. Five strains of A. alternata isolated from tomato and five isolated from cabbage were independently exposed in vitro to AITC and BITC. Concentrations were increased until it reached 0.08 and 0.6 mg/mL of AITC and BITC, respectively. Genomic DNA from both wild type and isogenic adapted strains to ITCs was isolated and five primers were used for ISSR amplification: (GACA) 4 :5´-GACAGACAGACAGACA-3´; M13:5´-GAGGGTGGCGGCGGTTCT-3´;(AAG) 8 :5´-AAGAAGAAGAAGAAGAAGAAGAAG-3´; (ACA) 5 : 5´-ACAACAACAACAACA-3´ and T3B: 5´-AGGTCGCGGGTTCGAATCC-3´. A lower degree of polymorphism was found to be induced by the treatment in the wild-type strains isolated from cabbage as compared with the wild-type strains isolated from tomato. It can be concluded that ITCs exposure induced random mutations in different ISSR regions of the A. alternata genome which does not lead to the development of strains with a hereditable resistant phenotype.
Modelado de la biodegradación en biorreactores de lodos de hidrocarburos totales del petróleo int... more Modelado de la biodegradación en biorreactores de lodos de hidrocarburos totales del petróleo intemperizados en suelos y sedimentos (Biodegradation modeling of sludge bioreactors of total petroleum hydrocarbons weathering in soil and sediments)
... 2 . Injector port and detectors (FID and TCD) were maintained at 250 °C, while oven temperatu... more ... 2 . Injector port and detectors (FID and TCD) were maintained at 250 °C, while oven temperature was kept at 50 °C for 30 s and then ... RR, EPR and accelerated fruit ripening, the extent of which depends on exposure time, type of fruit and its state of ripening ([Prasanna and Parva ...
Penelitian ini bertujuan untuk mengamati karakteristik kelistrikan pada lemak sapi dan lemak babi... more Penelitian ini bertujuan untuk mengamati karakteristik kelistrikan pada lemak sapi dan lemak babi dengan menggunakan metode dielektrik. Karakteristik kelistrikan yang diamati yaitu kapasitansi dan konstanta dielektrik. Kapasitansi diukur dengan menggunakan LCR meter GW-instek seri 816 dengan probe ganda L dan H, sedangkan konstanta dielektrik didapatkan dari nilai kapasitansinya. Pengukuran kapasitansi dilakukan pada frekuensi 800 Hz hingga 2000 Hz. Lemak babi sebagai pencemar ditambahkan pada lemak sapi dengan konsentrasi 0,5%, 1%, 5%, 10%, 20%, 30%, 40% dan 50%. Hasil penelitian menunjukkan bahwa metode dielektrik dapat digunakan untuk mengukur nilai kapasitansi dan konstanta dielektrik pada lemak sapi dan lemak babi. Kapasitansi yang terukur pada LCR meter yaitu 0,00142 nF-0,00263 nF, sedangkan konstanta dielektriknya yaitu 4,00726-7,42131. Nilai kapasitansi dan konstanta dielektrik lemak sapi lebih besar daripada lemak babi. Cemaran lemak babi pada lemak sapi menurunkan kapasitansi dan konstanta dielektrik lemak sapi.
β-galactosidase activity was studied as a possible cause of the low milk acidification ability ob... more β-galactosidase activity was studied as a possible cause of the low milk acidification ability observed in Lactobacillus reuteri NRRL 14171. Enzymatic activity was determined in MRS broth supplemented with either glucose or lactose and milk at the middle and final stage of the exponential phase, as well as at the stationary phase. Results were compared with β-galactosidase activity in Lactobacillus casei NRRL-B1922, a strain that shows the milk acidification ability. The effects of the types of carbon and nitrogen sources were established by comparison of growth parameters (higher maximum cell concentration and specific growth rate) in broth culture and skim milk supplemented with 2% glucose or 1% casein peptone. In milk, L. reuteri showed higher β-galactosidase activity in all growth phases compared with L. casei. Greater cell concentration maxima, specific growth rates, and acidification abilities were observed in L. reuteri when it was cultured in milk supplemented with 1% casein...
Pickering emulsions were prepared by using native and modified (esterification with lauroyl chlor... more Pickering emulsions were prepared by using native and modified (esterification with lauroyl chloride) amaranth starches as stabilizing particles of an oil phase formed with a mixture of canola oil and α-tocopherol (1% v/v). The effect of different concentrations of native (NS) and modified starch (MS) ranging from 2 to 30 %wt was evaluated in the emulsions regarding average droplet size, emulsion stability, zeta potential (ζ) and emulsification index. Optical microscopy showed that both NS and MS were adsorbed at the oil-water interface forming a barrier that delayed phase separation. The MS gave place to a smaller emulsion droplet size than NS, and no phase separation was detected for the emulsions prepared by using 20 and 30 % wt of NS or MS, producing stable emulsions.
This study investigated the effects of cooking treatments (boiling and steaming) and season of th... more This study investigated the effects of cooking treatments (boiling and steaming) and season of the year (spring and fall) on vitamin C content, total phenolics content (TPC), total flavonoids content (TFC), antioxidant activity and scavenging of nitric oxide (NO•), and superoxide radical (O 2-). After cooking, a significant decrease in vitamin C was observed (50 and 48.8% for boiling and 21 and 27.9% for steaming in spring and fall, respectively). TPC and TFC increased during steaming from 145-1480 mg GAE/kg and 348.6-797.2 mg QE/kg, respectively. DPPH values ranged from 2806-3801 μmol TE/kg and was affected by season whereas ORAC ranged from 1231.3-36,167.2 μmol TE/kg and was affected by cooking. The ability to scavenge NO• and O 2-, were not affected by neither cooking nor season. However, the inhibition of O 2 was higher for quintonil steamed in spring.
INTRODUCTION Medium chain fatty acids MCFAs are recognized for their health benefits. They are us... more INTRODUCTION Medium chain fatty acids MCFAs are recognized for their health benefits. They are used in enteral and parenteral nutrition for a series of medical conditions of patients suffering low absorption of fats, poor digestion, and metabolic difficulties related to cystic fibrosis, Crohn s disease, colitis and enteritis 1, 2. MCFAs with 6 to 14 carbons are of high interest for green chemistry due to their lathering and low-viscosity properties. They are widely used in detergents and lubricants. After esterification with alcohol, they can also be used as emulsifiers for foods and cosmetics, solvents for flavours, surface treatment of food products and as well as readily digestible fat in high-energy diets 3. In lipid research, thin layer chromatography TLC is commonly used for a rapid lipid fractionation and fatty acids profile characterizations. Nowadays, TLC constitutes a basic tool for modern analytical chemistry because of its
To study microwave heating for potential postharvest treatments against anthracnose disease, Coll... more To study microwave heating for potential postharvest treatments against anthracnose disease, Colletotrichum gloeosporioides growth–no-growth response after selected microwave treatments (2,450 MHz) was fitted by using a logistic regression model. Evaluated variables were power level, exposure time, presence or absence of water in the medium during treatment, and incubation-observation time. Depending on the setting, the applied power ranged from 77.2 to 435.6 W. For the experiments on dry medium (mold spores over filter paper), exposure times were 1, 2, 3, or 4 min, whereas spores dispersed in potato dextrose agar, a wet medium, had exposure times of 3, 6, or 9 s. Growth (response = 1) or no growth (response = 0) was observed after two different incubation-observation times (4 or 10 days). As expected, high power levels and long exposure times resulted in complete inhibition of C. gloeosporioides spore germination. In a number of cases (such as low power levels and short treatment t...
Milk-derived bioactive peptides with a single activity (e.g., antioxidant, immunomodulatory, or a... more Milk-derived bioactive peptides with a single activity (e.g., antioxidant, immunomodulatory, or antimicrobial) have been previously well documented; however, few studies describe multifunctional bioactive peptides, which may be preferred over single-activity peptides, as they can simultaneously trigger, modulate, or inhibit multiple physiological pathways. Hence, the aim of this study was to assess the anti-inflammatory, antihemolytic, antioxidant, antimutagenic, and antimicrobial activities of crude extracts (CE) and peptide fractions (<3 and 3-10 kDa) obtained from fermented milks with specific Lactobacillus plantarum strains. Overall, CE showed higher activity than both peptide fractions (<3 and 3-10 kDa) in most of the activities assessed. Furthermore, activity of <3 kDa was generally higher, or at least equal, to the 3 to 10 kDa peptide fractions. In particular, L. plantarum 55 crude extract or their fractions showed the higher anti-inflammatory (723.68-1,759.43 μg/mL of diclofenac sodium equivalents), antihemolytic (36.65-74.45% of inhibition), and antioxidant activity [282.8-362.3 μmol of Trolox (Sigma-Aldrich, St. Louis, MO) equivalents]. These results provide valuable evidence of multifunctional role of peptides derived of fermented milk by the action of specific L. plantarum strains. Thus, they may be considered for the development of biotechnological products to be used to reduce the risk of disease or to enhance a certain physiological function.
This study was aimed to prepare and characterize capsules loaded with Lacticaseibacillus rhamnosu... more This study was aimed to prepare and characterize capsules loaded with Lacticaseibacillus rhamnosus GG (LGG), evaluating cell viability under gastrointestinal in vitro conditions and during storage in yogurt and apple juice, an alternative to traditional probiotic foods for people who are lactose intolerant. The capsules were prepared by ionic gelation, with an emulsification process as pretreatment. Cell viability of encapsulated LGG was evaluated after two different homogenization processes: magnetic stirring (AM) and Ultraturrax® homogenizer (UT). The system with the best relationship between viability and morphology was UT, which produced a viability of 85.80%. During in vitro evaluation, the capsules provided higher protection than free cells, up to 100% of cell viability. The morphology of capsules of both systems displayed a continuous and homogeneous surface. The cell viability of the encapsulated probiotics added in apple juice stored for 22 days at 4 °C was 86.16% for AM an...
Haden mango slices (non-osmotic dehydrated, NOD) were immersed in calcium chloride (2 g/l), citri... more Haden mango slices (non-osmotic dehydrated, NOD) were immersed in calcium chloride (2 g/l), citric acid (5 g/l), hydrogen peroxide (25 ml/l) and sodium benzoate (20 g/l) solutions. Slices to be treated with osmotic dehydration (OD) were first immersed in calcium, then placed in the osmotic solution (sucrose 65 • Bx, 30 • C) and 211 mbar vacuum was applied for 30 min. After the osmotic treatment, the slices were immersed in the same solutions as for NOD slices. All the slices were stored in sterile chambers at 24, 13 or 5 • C. Both OD and NOD slices displayed sucrose synthesis (SS) during storage, which was highest in NOD slices that were kept at 13 • C. Sucrose synthesis was the most significant change during ripening of whole mangoes (WM). Starch breakdown could not supply the necessary substrates for sucrose synthesis in either whole mangoes or slices. Injured tissues from mango slices sustained sucrose synthesis, which was highest at 13 • C in NOD slices, but the osmotic treatment decreased sucrose formation. Storage at 5 • C for 12 days affected sucrose content of Haden mangoes. Glucose and fructose concentrations remained low in all treatments.
View related articles Citing articles: 3 View citing articles Conjugated linoleic acid content in... more View related articles Citing articles: 3 View citing articles Conjugated linoleic acid content in selected Mexican beef and dairy products Contenido de a´cido linoleico conjugado en carne de res y la´cteos Mexicanos seleccionados
The aims of this work were to estimate the content of acrylamide (AA) in food consumed by young p... more The aims of this work were to estimate the content of acrylamide (AA) in food consumed by young people in Mexico and calculate its intake in this population sector. Fifteen samples of heat-processed commercial foods, widely consumed in Mexico obtained from supermarkets and local convenience stores, and analyzed in triplicate to determine their concentration of acrylamide (µg/kg of product) by HPLC-UV and later assess the intake in young adults. Significantly high contents of acrylamide were found in most foods evaluated; the highest levels were found in fried products (5,914 µg/kg of product in potato chips). Based on food and portions that subjects reported, an intake of Acrylamide of 0.68 µg/kg bw/day was estimated. The estimated daily intake could be at levels above the limit established to avoid the risk of neurotoxicity. This research provides relevant information for public health experts, policy makers and consumers in general.
En este trabajo se utilizo una lipasa de Candida antarctica para la produccion de mono-, di- y tr... more En este trabajo se utilizo una lipasa de Candida antarctica para la produccion de mono-, di- y tri-acilgliceroles por esterificacion directa de acidos grasos poliinsaturados (AGPI) n-3 al glicerol. Se preparo un concentrado de AGPI n-3 (81,5% w/w) por hidrolisis quimica del aceite de sardina seguido de un tratamiento con urea. Las reacciones de esterificacion se realizaron colocando una proporcion de 2.62 mol AGPI n-3/mol glicerol en frascos de vidrio completamente sellados, agitados continuamente, manteniendo la temperatura constante (55°C). Las muestras se extrajeron a diferentes tiempos y se analizo el contenido de acilgliceroles por medio de HPLC-ELSD. Se desarrollo un modelo cinetico basado en un mecanismo de ping-pong multi-sustrato multi-producto para interpretar los datos experimentales. Se estimaron los parametros del modelo mediante regresion no-lineal sin restricciones en una plataforma MATLAB® (R2014a), con un coeficiente de determinacion (R 2 >0.9). El modelo obtenid...
Se han evaluado los cambios fisiologicos durante la maduracion de platanos pelados y sin pelar al... more Se han evaluado los cambios fisiologicos durante la maduracion de platanos pelados y sin pelar almacenados en camaras con atmosferas automodificadas. Se colocaron tres lotes de frutos en frascos de vidrio sellados y se mantuvieron a 20 ± 0,5o C. Se envasaron platanos enteros pelados y sin pelar dentro de frascos de vidrio y se dejaron sin envasar platanos enteros sin pelar como testigo. El pelado de los platanos verdes y firmes no ocasiono ningun tipo de deterioro ni interferencia en la maduracion normal cuando los platanos se mantuvieron dentro de las camaras de atmosferas automodificadas. La maduracion de los platanos pelados dentro de las atmosferas automodificadas fue similar al del testigo.
compendiou a reflexão renascentista sobre a arte de traduzir produzindo o ingente tratado Interpr... more compendiou a reflexão renascentista sobre a arte de traduzir produzindo o ingente tratado Interpretatio linguarum (Tradução de línguas), publicado em 1559. Dividido em três livros, com mais de 600 páginas, o tratado do teólogo puritano inglês, que, apesar de sua reconhecida importância, nunca foi reimpresso, nem recebeu edição crítica ou tradução integral a qualquer língua até hoje, é aqui apresentado em tradução ao português brasileiro. Abdicando de boa parte dos inúmeros exemplos oferecidos por Humphrey, selecionamos para esta publicação excertos do primeiro livro, o mais teórico de seu tratado, intitulado De ratione interpretandi (Da arte de traduzir).
Current changes in diet, characterized by an increase in the intake of sweetened beverages, are h... more Current changes in diet, characterized by an increase in the intake of sweetened beverages, are heavily related to metabolic disorders such as non-alcoholic fatty liver. This condition can produce simple steatosis and, in worse cases, potentially result in steatohepatitis, fibrosis, and cirrhosis, comparable to the damage caused by the consumption of more or less 20–30 g of alcohol per day. The main objective of this research was to evaluate the effect of curcumin (Curcuma longa) nanoemulsions, using mono- and diacylglycerides medium chain fatty acids as stabilizers in an in vivo hepatic steatosis rat model. Pathology was induced by providing 30% fructose intake in the drinking water. Globule sizes under 200 nm that were stable for 4 weeks were obtained; curcumin encapsulated in the nanoemulsion was >70%. The results revealed an improvement regarding body and liver weight in the animals treated with curcumin nanoemulsions. A decrease in total cholesterol, LDL, AST/ALT, and HDL in...
Structured phosphatidylcholine was successfully produced by acidolysis between phosphatidylcholin... more Structured phosphatidylcholine was successfully produced by acidolysis between phosphatidylcholine and free medium chain fatty acid, using phospholipase A1 immobilized on Duolite A568. Response surface methodology was applied to optimize the reaction system using three process parameters: molar ratio of substrates (phosphatidylcholine to free medium chain fatty acid), enzyme loading, and reaction temperature. All parameters evaluated showed linear and quadratic significant effects on the production of modified phosphatidylcholine; molar ratio of substrates contributed positively, but temperature influenced negatively. Increased enzyme loading also led to increased production of modified phosphatidylcholine but only during the first 9 hours of the acidolysis reaction. Optimal conditions obtained from the model were a ratio of phosphatidylcholine to free medium chain fatty acid of 1:15, an enzyme loading of 12%, and a temperature of 45°C. Under these conditions a production of modifie...
African Journal of Microbiology Research, Mar 5, 2013
Isothiocyanates (ITCs) is a group of defense related compounds synthesized by Brassicas that have... more Isothiocyanates (ITCs) is a group of defense related compounds synthesized by Brassicas that have positive effects on human health which suggest that they are environmentally friendly compounds to control fungi infections. However, the development of ITC-resistant strains of fungi is a matter of concern. The objective of the present work was to study the response of Alternaria alternata to allylisothiocyanate (AITC) and benzyl isothiocyanate (BITC) chronic exposure and the effect of the treatment on some of the inter simple sequence repeats (ISSR) regions. Five strains of A. alternata isolated from tomato and five isolated from cabbage were independently exposed in vitro to AITC and BITC. Concentrations were increased until it reached 0.08 and 0.6 mg/mL of AITC and BITC, respectively. Genomic DNA from both wild type and isogenic adapted strains to ITCs was isolated and five primers were used for ISSR amplification: (GACA) 4 :5´-GACAGACAGACAGACA-3´; M13:5´-GAGGGTGGCGGCGGTTCT-3´;(AAG) 8 :5´-AAGAAGAAGAAGAAGAAGAAGAAG-3´; (ACA) 5 : 5´-ACAACAACAACAACA-3´ and T3B: 5´-AGGTCGCGGGTTCGAATCC-3´. A lower degree of polymorphism was found to be induced by the treatment in the wild-type strains isolated from cabbage as compared with the wild-type strains isolated from tomato. It can be concluded that ITCs exposure induced random mutations in different ISSR regions of the A. alternata genome which does not lead to the development of strains with a hereditable resistant phenotype.
Modelado de la biodegradación en biorreactores de lodos de hidrocarburos totales del petróleo int... more Modelado de la biodegradación en biorreactores de lodos de hidrocarburos totales del petróleo intemperizados en suelos y sedimentos (Biodegradation modeling of sludge bioreactors of total petroleum hydrocarbons weathering in soil and sediments)
... 2 . Injector port and detectors (FID and TCD) were maintained at 250 °C, while oven temperatu... more ... 2 . Injector port and detectors (FID and TCD) were maintained at 250 °C, while oven temperature was kept at 50 °C for 30 s and then ... RR, EPR and accelerated fruit ripening, the extent of which depends on exposure time, type of fruit and its state of ripening ([Prasanna and Parva ...
Penelitian ini bertujuan untuk mengamati karakteristik kelistrikan pada lemak sapi dan lemak babi... more Penelitian ini bertujuan untuk mengamati karakteristik kelistrikan pada lemak sapi dan lemak babi dengan menggunakan metode dielektrik. Karakteristik kelistrikan yang diamati yaitu kapasitansi dan konstanta dielektrik. Kapasitansi diukur dengan menggunakan LCR meter GW-instek seri 816 dengan probe ganda L dan H, sedangkan konstanta dielektrik didapatkan dari nilai kapasitansinya. Pengukuran kapasitansi dilakukan pada frekuensi 800 Hz hingga 2000 Hz. Lemak babi sebagai pencemar ditambahkan pada lemak sapi dengan konsentrasi 0,5%, 1%, 5%, 10%, 20%, 30%, 40% dan 50%. Hasil penelitian menunjukkan bahwa metode dielektrik dapat digunakan untuk mengukur nilai kapasitansi dan konstanta dielektrik pada lemak sapi dan lemak babi. Kapasitansi yang terukur pada LCR meter yaitu 0,00142 nF-0,00263 nF, sedangkan konstanta dielektriknya yaitu 4,00726-7,42131. Nilai kapasitansi dan konstanta dielektrik lemak sapi lebih besar daripada lemak babi. Cemaran lemak babi pada lemak sapi menurunkan kapasitansi dan konstanta dielektrik lemak sapi.
β-galactosidase activity was studied as a possible cause of the low milk acidification ability ob... more β-galactosidase activity was studied as a possible cause of the low milk acidification ability observed in Lactobacillus reuteri NRRL 14171. Enzymatic activity was determined in MRS broth supplemented with either glucose or lactose and milk at the middle and final stage of the exponential phase, as well as at the stationary phase. Results were compared with β-galactosidase activity in Lactobacillus casei NRRL-B1922, a strain that shows the milk acidification ability. The effects of the types of carbon and nitrogen sources were established by comparison of growth parameters (higher maximum cell concentration and specific growth rate) in broth culture and skim milk supplemented with 2% glucose or 1% casein peptone. In milk, L. reuteri showed higher β-galactosidase activity in all growth phases compared with L. casei. Greater cell concentration maxima, specific growth rates, and acidification abilities were observed in L. reuteri when it was cultured in milk supplemented with 1% casein...
Pickering emulsions were prepared by using native and modified (esterification with lauroyl chlor... more Pickering emulsions were prepared by using native and modified (esterification with lauroyl chloride) amaranth starches as stabilizing particles of an oil phase formed with a mixture of canola oil and α-tocopherol (1% v/v). The effect of different concentrations of native (NS) and modified starch (MS) ranging from 2 to 30 %wt was evaluated in the emulsions regarding average droplet size, emulsion stability, zeta potential (ζ) and emulsification index. Optical microscopy showed that both NS and MS were adsorbed at the oil-water interface forming a barrier that delayed phase separation. The MS gave place to a smaller emulsion droplet size than NS, and no phase separation was detected for the emulsions prepared by using 20 and 30 % wt of NS or MS, producing stable emulsions.
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Papers by Hugo García