Harlen Torres Castañeda - Academia.edu (original) (raw)
Papers by Harlen Torres Castañeda
Revista Ingenieria E Investigacion, 2012
Se desarrolló una metodología de superficie de respuesta, diseño Box-Benkhen, con el fin de optim... more Se desarrolló una metodología de superficie de respuesta, diseño Box-Benkhen, con el fin de optimizar el proceso foto-Fenton para la degradación de carbofurano (C 12 H 15 NO 3) usando una planta piloto de colectores solares cilindro-parabólicos. El modelo Box-Benkhen incluyó cuatro variables: porcentaje de degradación de carbofurano, concentración inicial de carbofurano, concentración de peróxido de hidrógeno [H 2 O 2 ] y concentración de hierro [Fe 2+ ]. El proceso de degradación fue monitoreado a través de la concentración de carbono orgánico total y cromatografía líquida de alta resolución. Los resultados mostraron que una concentración de 93,2 mg l-1 de carbofurano se degradó completamente en un tiempo t 30W = 15 min con 17,1 mg l-1 de Fe 2+ y 121,6 mg l-1 de H 2 O 2. El proceso foto-Fenton alcanzó 76,7% de mineralización. La biodegradabilidad fue evaluada usando la relación DBO 5 /DQO; este valor incrementó desde 0,04 hasta 0,52 en t 30W = 20 min, mostrando la posibilidad de usar un tratamiento biológico a partir de ese momento.
Acta Agronómica
Moringa oleifera es una especie vegetal con múltiples aplicaciones y características importantes ... more Moringa oleifera es una especie vegetal con múltiples aplicaciones y características importantes de uso medicinal y farmacológico, contiene compuestos que le confieren actividad antioxidante, anticancerígena y antiinflamatoria, entre otras propiedades. Las hojas son la estructura más utilizada y con mayor concentración de compuestos bioactivos que pueden ser parcialmente aislados en extractos para usos posteriores. Sin embargo, en Colombia los estudios relacionados con la especie son escasos, lo que generó la necesidad de evaluar los compuestos fenólicos y la capacidad antioxidante de las hojas de esta planta en tres estados fenológicos (J: joven, M: madura, A: adulta). Los extractos fueron evaluados en términos del contenido total de fenoles (CTF), flavonoides (CTFl), catequinas (CTC) y la capacidad antioxidante (DPPH, FRAP y ABTS). Los resultados obtenidos en este estudio evidenciaron que entre la hoja joven y madura no hubo diferencia estadística en ninguno de los parámetros eva...
Food Science and Technology
The extraction of value-added compounds from agro-industrial wastes is important to reduce their ... more The extraction of value-added compounds from agro-industrial wastes is important to reduce their environmental impact. In this research, the time for ultrasound-assisted extraction of phenolic compounds obtained from goldenberry (Physalis peruviana L.) calyx was first chosen. Subsequently, response surface methodology was used to optimise the effect of wave amplitude, liquid:solid ratio, and particle size on total phenol content and in vitro antioxidant capacity. Then, antioxidant capacity (DPPH, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), and ferric reducing antioxidant power) was measured in the extract obtained under optimal conditions, and rutin flavanol was identified and quantified by HPLC-DAD. Analysis of polynomial models indicated adequate fit (p≤0.05) for phenolic content (R2=0.98) and antioxidant capacity (R2=0.91). Optimal amplitude (54%), liquid:solid ratio (33 mL/g), and particle size (213 µm) maximised the response of phenolic content (53 mg GAE/g) and ant...
Ingeniería e Investigación
Box-Benkhen design response-surface methodology was developed to optimise photo-Fenton degradatio... more Box-Benkhen design response-surface methodology was developed to optimise photo-Fenton degradation of carbofuran (C12H15NO3) by using a compound parabolic collector pilot plant. The four variables considered in Box-Benkhen design model included carbofuran degradation percentage, initial carbofuran concentration, hydrogen peroxide [H2O2] concentration and iron [Fe2+] concentration. Degradation was monitored by using total organic carbon concentration and high-performance liquid chromatography. A 93.2 mg l-1 carbofuran concentration was completely degraded in t30W = 15 min with 17.1 mg l;-1 Fe2+ and 121.6 mg l-1 H2O2. Photo-Fenton degradation led to 76.7% mineralisation. Biodegradability during optimisation was evaluated by using the BOD5/COD ratio; this value increased from 0.04 at the beginning of the process to 0.52 in t30W = 20 min, thereby showing the effectiveness of using biological treatments.
Fermentation
The exploration of natural antimicrobial compounds is necessary due to the current bacterial resi... more The exploration of natural antimicrobial compounds is necessary due to the current bacterial resistance to synthetic antibiotics. For this reason, pineapple residues were evaluated as a natural source of phenolic compounds with antimicrobial capacity. Pineapple residues were fermented with A. niger GH1 and subjected to ultrasound for the extraction of phenolic compounds. In the solid-state fermentation (SSF), the peel and the core (70:30) were fermented for 32 h. Ultrasonic-assisted extraction (UAE) was optimized. The factors solid–liquid ratio (X1), ethanol concentration (X2), and extraction cycle (X3) were optimized through a Box–Behnken statistical design, using the total phenol content (TPC) as a response variable. The optimized and pre-purified extract with amberlite was characterized using HPLC-MS and we measured the antimicrobial activity against Listeria monocytogenes, Staphylococcus aureus, and Escherichia coli. The optimal values for X1, X2, and X3 were 82 mg/mL, 26%, and ...
Ingeniería e Investigación
This article describes the results of a bibliographic review of the effects of operation conditio... more This article describes the results of a bibliographic review of the effects of operation conditions on process yield in the chemical transesterification of vegetable oil. The parameters studied were: temperature and time reaction, alcohol: oil molar ratio, catalyst and alcohol type, catalyst concentration, mixed intensity and free fatty acid and water concentration. It also reports that this process has been carried out with basic and acid catalysts using homogeneous and heterogeneous catalytic processes for a wide variety of oils. It was found that reaction yield increased when temperature and time reaction increased; however this parameter decreased at low catalyst concentration (<0.5 % w/w) and high free fatty acid (> 1% w/w) and water (> 3% w/w) concentration in oil.
International Journal of Food Science
The present study compared the extracts obtained from the epicarp, seed, and seed tegument of avo... more The present study compared the extracts obtained from the epicarp, seed, and seed tegument of avocado var. Hass with pressurized liquid extraction (PLE) and ultrasound-assisted extraction (UAE). The extracts were quantified in terms of total phenolic content (TPC) and antioxidant capacity (AC). The PLE extracts had a global yield ( X 0 ) like that obtained with UAE using ethanol (Et) as the solvent. For the TPC, the extracts obtained with both techniques showed no significant differences ( p > 0.05 ). On the other hand, the epicarp extracts obtained with PLE had higher values for AC: 829.8 μmol TE/gDe (ABTS) and 3,215.1 μmol Fe2+/g De (FRAP), recorded for UAE/Et. The AC in the avocado residue extracted with PLE suggested a high potential for applications in food, pharmaceutical, and cosmetology products.
Revista de Ciencias, 2014
Determining the antioxidant activity and the total phenolic content are routine procedures in mos... more Determining the antioxidant activity and the total phenolic content are routine procedures in most natural product laboratories; however, when dealing with large number of samples, it is necessary to employ methods that allow a quick, easy and economical screening. The aim of this study is to determine the antioxidant activity and the total phenolic content of plant species as criteria for the selection of promising species. To reach this aim, we used twenty species from Yotoco National Protected Forest in Valle del Cauca, Colombia. The species Clidemia tococoidea and Miconia aeruginosa, showed the highest total phenolic content together with the best antioxidant activity in terms of DPPH radical scavenging activity. The excellent correlation (R2=0.9610) shown between these parameters, demonstrated the utility of the process used as a method for primary screening and selection of promising species for phytochemical analysis at a preparative scale for this two assays.
Journal of Chromatographic Science, 2013
In the 70s, reports began to appear of phenolic metabolites of brown algae with the characteristi... more In the 70s, reports began to appear of phenolic metabolites of brown algae with the characteristics of tannins; these compounds, initially termed phaeophyte tannins, marine algal polyphenols or polyphloroglucinols, are known as phlorotannins, the youngest group of plant polyphenolics. Despite over 40 years of research in phlorotannins, this area is still in the exponential growth phase; however, several reviews have appeared, primarily concerning their biological activity. This review focuses on techniques for the extraction, isolation and chromatographic purification of approximately 150 phlorotannins during these four decades. Due to the high structural diversity of these polyphenols and the difficulty of classification, these topics are also reviewed: structural diversity and classification, extraction and preparative chromatography, thin-layer chromatography, and analytical high-performance liquid chromatography (HPLC) and HPLC-mass spectrometry. These techniques have primarily been used for separation monitoring and qualitative profiles, and not too many reports have been published on the development of quantification or quality control.
La composicion quimica del aceite esencial obtenido a partir de las hojas de varias plantas aroma... more La composicion quimica del aceite esencial obtenido a partir de las hojas de varias plantas aromaticas en condiciones del Valle del Cauca, fue analizada mediante GC/MS. Los compuestos quimicos mas representativos fueron la Elemicina (40.11 por ciento) en Artemisia dracunculus Linn, el s-Himachaleno (53.98 por ciento) en Franseria artemisioides Willd, trans-s-Cariofileno (22.18) en Salvia officinalis Linn, a-Bisabolol (15.79 por ciento) en Lippia dulcis Frev y 1,8- Cineol (Eucaliptol) (23.34 por ciento) en Occimun americanum Auct. Ex Benth. Las propiedades fisicas fueron congruentes con la presencia de los compuestos quimicos encontrados. Todos los aceites esenciales presentaron usos agroindustriales potenciales, variando estos de acuerdo a la especie y a sus componentes .
CHEMICAL & PHARMACEUTICAL BULLETIN, 2016
Two new flavonol glycosides were isolated from the leaves of Siparuna gigantotepala. Their struct... more Two new flavonol glycosides were isolated from the leaves of Siparuna gigantotepala. Their structures were determined to be kaempferol 3-O-β-xylopyranosyl-(1→2)-α-arabinofuranoside (1) and kaempferol 3,7-di-O-methyl-4′-O-α-rhamnopyranosyl-(1→2)-β-glucopyranoside (2). In addition, three known flavonol glycosides, rutin (3), kaempferol 3-O-rutinoside (4), and kaempferol 3,7-di-O-methyl-4′-O-rutinoside (5), and three flavonol aglycones, quercetin (6), kaempferol 3,7-dimethyl ether (7), and kaempferol 3,7,4′-trimethyl ether (8), were also isolated and are reported here for the first time in this species. The structures of compounds 1 and 2 were established on the basis of their LC-MS and one-and two-dimensional (1D)-and (2D)-NMR spectroscopic analyses, combined with acid methanolysis and silylation of sugar moieties for GC-MS. Evaluation of the antioxidant activity, conducted in the 96-well plate format, showed that the flavonoids isolated possess strong 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity and moderate oxygen radical absorption capacity.
Revista Ingenieria E Investigacion, 2012
Se desarrolló una metodología de superficie de respuesta, diseño Box-Benkhen, con el fin de optim... more Se desarrolló una metodología de superficie de respuesta, diseño Box-Benkhen, con el fin de optimizar el proceso foto-Fenton para la degradación de carbofurano (C 12 H 15 NO 3) usando una planta piloto de colectores solares cilindro-parabólicos. El modelo Box-Benkhen incluyó cuatro variables: porcentaje de degradación de carbofurano, concentración inicial de carbofurano, concentración de peróxido de hidrógeno [H 2 O 2 ] y concentración de hierro [Fe 2+ ]. El proceso de degradación fue monitoreado a través de la concentración de carbono orgánico total y cromatografía líquida de alta resolución. Los resultados mostraron que una concentración de 93,2 mg l-1 de carbofurano se degradó completamente en un tiempo t 30W = 15 min con 17,1 mg l-1 de Fe 2+ y 121,6 mg l-1 de H 2 O 2. El proceso foto-Fenton alcanzó 76,7% de mineralización. La biodegradabilidad fue evaluada usando la relación DBO 5 /DQO; este valor incrementó desde 0,04 hasta 0,52 en t 30W = 20 min, mostrando la posibilidad de usar un tratamiento biológico a partir de ese momento.
Acta Agronómica
Moringa oleifera es una especie vegetal con múltiples aplicaciones y características importantes ... more Moringa oleifera es una especie vegetal con múltiples aplicaciones y características importantes de uso medicinal y farmacológico, contiene compuestos que le confieren actividad antioxidante, anticancerígena y antiinflamatoria, entre otras propiedades. Las hojas son la estructura más utilizada y con mayor concentración de compuestos bioactivos que pueden ser parcialmente aislados en extractos para usos posteriores. Sin embargo, en Colombia los estudios relacionados con la especie son escasos, lo que generó la necesidad de evaluar los compuestos fenólicos y la capacidad antioxidante de las hojas de esta planta en tres estados fenológicos (J: joven, M: madura, A: adulta). Los extractos fueron evaluados en términos del contenido total de fenoles (CTF), flavonoides (CTFl), catequinas (CTC) y la capacidad antioxidante (DPPH, FRAP y ABTS). Los resultados obtenidos en este estudio evidenciaron que entre la hoja joven y madura no hubo diferencia estadística en ninguno de los parámetros eva...
Food Science and Technology
The extraction of value-added compounds from agro-industrial wastes is important to reduce their ... more The extraction of value-added compounds from agro-industrial wastes is important to reduce their environmental impact. In this research, the time for ultrasound-assisted extraction of phenolic compounds obtained from goldenberry (Physalis peruviana L.) calyx was first chosen. Subsequently, response surface methodology was used to optimise the effect of wave amplitude, liquid:solid ratio, and particle size on total phenol content and in vitro antioxidant capacity. Then, antioxidant capacity (DPPH, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), and ferric reducing antioxidant power) was measured in the extract obtained under optimal conditions, and rutin flavanol was identified and quantified by HPLC-DAD. Analysis of polynomial models indicated adequate fit (p≤0.05) for phenolic content (R2=0.98) and antioxidant capacity (R2=0.91). Optimal amplitude (54%), liquid:solid ratio (33 mL/g), and particle size (213 µm) maximised the response of phenolic content (53 mg GAE/g) and ant...
Ingeniería e Investigación
Box-Benkhen design response-surface methodology was developed to optimise photo-Fenton degradatio... more Box-Benkhen design response-surface methodology was developed to optimise photo-Fenton degradation of carbofuran (C12H15NO3) by using a compound parabolic collector pilot plant. The four variables considered in Box-Benkhen design model included carbofuran degradation percentage, initial carbofuran concentration, hydrogen peroxide [H2O2] concentration and iron [Fe2+] concentration. Degradation was monitored by using total organic carbon concentration and high-performance liquid chromatography. A 93.2 mg l-1 carbofuran concentration was completely degraded in t30W = 15 min with 17.1 mg l;-1 Fe2+ and 121.6 mg l-1 H2O2. Photo-Fenton degradation led to 76.7% mineralisation. Biodegradability during optimisation was evaluated by using the BOD5/COD ratio; this value increased from 0.04 at the beginning of the process to 0.52 in t30W = 20 min, thereby showing the effectiveness of using biological treatments.
Fermentation
The exploration of natural antimicrobial compounds is necessary due to the current bacterial resi... more The exploration of natural antimicrobial compounds is necessary due to the current bacterial resistance to synthetic antibiotics. For this reason, pineapple residues were evaluated as a natural source of phenolic compounds with antimicrobial capacity. Pineapple residues were fermented with A. niger GH1 and subjected to ultrasound for the extraction of phenolic compounds. In the solid-state fermentation (SSF), the peel and the core (70:30) were fermented for 32 h. Ultrasonic-assisted extraction (UAE) was optimized. The factors solid–liquid ratio (X1), ethanol concentration (X2), and extraction cycle (X3) were optimized through a Box–Behnken statistical design, using the total phenol content (TPC) as a response variable. The optimized and pre-purified extract with amberlite was characterized using HPLC-MS and we measured the antimicrobial activity against Listeria monocytogenes, Staphylococcus aureus, and Escherichia coli. The optimal values for X1, X2, and X3 were 82 mg/mL, 26%, and ...
Ingeniería e Investigación
This article describes the results of a bibliographic review of the effects of operation conditio... more This article describes the results of a bibliographic review of the effects of operation conditions on process yield in the chemical transesterification of vegetable oil. The parameters studied were: temperature and time reaction, alcohol: oil molar ratio, catalyst and alcohol type, catalyst concentration, mixed intensity and free fatty acid and water concentration. It also reports that this process has been carried out with basic and acid catalysts using homogeneous and heterogeneous catalytic processes for a wide variety of oils. It was found that reaction yield increased when temperature and time reaction increased; however this parameter decreased at low catalyst concentration (<0.5 % w/w) and high free fatty acid (> 1% w/w) and water (> 3% w/w) concentration in oil.
International Journal of Food Science
The present study compared the extracts obtained from the epicarp, seed, and seed tegument of avo... more The present study compared the extracts obtained from the epicarp, seed, and seed tegument of avocado var. Hass with pressurized liquid extraction (PLE) and ultrasound-assisted extraction (UAE). The extracts were quantified in terms of total phenolic content (TPC) and antioxidant capacity (AC). The PLE extracts had a global yield ( X 0 ) like that obtained with UAE using ethanol (Et) as the solvent. For the TPC, the extracts obtained with both techniques showed no significant differences ( p > 0.05 ). On the other hand, the epicarp extracts obtained with PLE had higher values for AC: 829.8 μmol TE/gDe (ABTS) and 3,215.1 μmol Fe2+/g De (FRAP), recorded for UAE/Et. The AC in the avocado residue extracted with PLE suggested a high potential for applications in food, pharmaceutical, and cosmetology products.
Revista de Ciencias, 2014
Determining the antioxidant activity and the total phenolic content are routine procedures in mos... more Determining the antioxidant activity and the total phenolic content are routine procedures in most natural product laboratories; however, when dealing with large number of samples, it is necessary to employ methods that allow a quick, easy and economical screening. The aim of this study is to determine the antioxidant activity and the total phenolic content of plant species as criteria for the selection of promising species. To reach this aim, we used twenty species from Yotoco National Protected Forest in Valle del Cauca, Colombia. The species Clidemia tococoidea and Miconia aeruginosa, showed the highest total phenolic content together with the best antioxidant activity in terms of DPPH radical scavenging activity. The excellent correlation (R2=0.9610) shown between these parameters, demonstrated the utility of the process used as a method for primary screening and selection of promising species for phytochemical analysis at a preparative scale for this two assays.
Journal of Chromatographic Science, 2013
In the 70s, reports began to appear of phenolic metabolites of brown algae with the characteristi... more In the 70s, reports began to appear of phenolic metabolites of brown algae with the characteristics of tannins; these compounds, initially termed phaeophyte tannins, marine algal polyphenols or polyphloroglucinols, are known as phlorotannins, the youngest group of plant polyphenolics. Despite over 40 years of research in phlorotannins, this area is still in the exponential growth phase; however, several reviews have appeared, primarily concerning their biological activity. This review focuses on techniques for the extraction, isolation and chromatographic purification of approximately 150 phlorotannins during these four decades. Due to the high structural diversity of these polyphenols and the difficulty of classification, these topics are also reviewed: structural diversity and classification, extraction and preparative chromatography, thin-layer chromatography, and analytical high-performance liquid chromatography (HPLC) and HPLC-mass spectrometry. These techniques have primarily been used for separation monitoring and qualitative profiles, and not too many reports have been published on the development of quantification or quality control.
La composicion quimica del aceite esencial obtenido a partir de las hojas de varias plantas aroma... more La composicion quimica del aceite esencial obtenido a partir de las hojas de varias plantas aromaticas en condiciones del Valle del Cauca, fue analizada mediante GC/MS. Los compuestos quimicos mas representativos fueron la Elemicina (40.11 por ciento) en Artemisia dracunculus Linn, el s-Himachaleno (53.98 por ciento) en Franseria artemisioides Willd, trans-s-Cariofileno (22.18) en Salvia officinalis Linn, a-Bisabolol (15.79 por ciento) en Lippia dulcis Frev y 1,8- Cineol (Eucaliptol) (23.34 por ciento) en Occimun americanum Auct. Ex Benth. Las propiedades fisicas fueron congruentes con la presencia de los compuestos quimicos encontrados. Todos los aceites esenciales presentaron usos agroindustriales potenciales, variando estos de acuerdo a la especie y a sus componentes .
CHEMICAL & PHARMACEUTICAL BULLETIN, 2016
Two new flavonol glycosides were isolated from the leaves of Siparuna gigantotepala. Their struct... more Two new flavonol glycosides were isolated from the leaves of Siparuna gigantotepala. Their structures were determined to be kaempferol 3-O-β-xylopyranosyl-(1→2)-α-arabinofuranoside (1) and kaempferol 3,7-di-O-methyl-4′-O-α-rhamnopyranosyl-(1→2)-β-glucopyranoside (2). In addition, three known flavonol glycosides, rutin (3), kaempferol 3-O-rutinoside (4), and kaempferol 3,7-di-O-methyl-4′-O-rutinoside (5), and three flavonol aglycones, quercetin (6), kaempferol 3,7-dimethyl ether (7), and kaempferol 3,7,4′-trimethyl ether (8), were also isolated and are reported here for the first time in this species. The structures of compounds 1 and 2 were established on the basis of their LC-MS and one-and two-dimensional (1D)-and (2D)-NMR spectroscopic analyses, combined with acid methanolysis and silylation of sugar moieties for GC-MS. Evaluation of the antioxidant activity, conducted in the 96-well plate format, showed that the flavonoids isolated possess strong 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity and moderate oxygen radical absorption capacity.