Browsing by Autor "Yonny Flores"

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1,3,7-TRIMETHYLGUANINE FROM THE LICHEN STEREOCAULON RAMULOSUM
(Universidad Autónoma del Estado de México, 2008) José Vila; Patricia Mollinedo; Yonny Flores; Olov Sterner
"Chromatographic fractionation of an acetone extract of the lichen Stereocaulon ramulosum afforded 1,3,7- trimethylguanine (1), perlatolic acid (2), methyl β-orcinolcarboxylate (3), atranorin (4) and galactitol (5). The structures were elucidated using NMR spectroscopy and mass spectrometry./ Cinco compuestos fueron aislados del extracto acetónico del Stereocaulon ramulosum, 1,3,7-trimetilguanina (1), acido perlatólico (2), β- orcinolcarboxilato de metilo (3), atranorina (4) y galactitol (5). Las estructuras moleculares fueron elucidadas por métodos espectroscópicos de RMN y espectrometría de masas."
A 5-methylcoumarin glucoside and a coumestan derivative from Mutisia orbignyana.
(Lund University, 2009) Yonny Flores; Gloria Rodrigo; Patricia Mollinedo; Björn Åkesson; Olov Sterner; Giovanna R. Almanza
The ethanolic extract of the aerial parts from Mutisia orbignyana afforded two major compounds: mutisifurocoumarin (1) and 5-methylcoumarine-4-β-glucoside (2). The completely assignment of 1H and 13C NMR data of compound (2) is presented for the first time as well as some reassignments of 13C NMR spectrum for compound (1), applying 2D NMR techniques. In addition, the antiproliferative effect on colon cancer cells (CaCo2) and the scavenging effect using the ABTS test were measured The results showed an interesting scavenging activity and a non proliferative effect on colon cancer cells./El extracto etanólico de las partes aéreas de Mutisia orbignyana presentó dos compuestos mayoritarios: mutisifurocumarina (1) y 5-metilcumarina-4-β-glucosilada (2). El asignamiento completo de RMN de 1H y 13C del compuesto (2) es presentado por primera vez, así como también algunos reasignamientos del espectro de RMN13C del compuesto (1), en ambos casos se aplico técnicas de RMN 2D. Además, se midió el efecto antiproliferativo sobre células cancerosas de colon (CaCo2) y el efecto como inhibidores de radicales libres usando la prueba ABTS, tanto de extractos como de compuestos puros. Los resultados muestran un interesante efecto antiradicalario en ABTS y un efecto no-proliferativo sobre células cancerosas de colon.
Analytical Methods for Identification and Quantification of Quinoa Saponins: A Review
(American Chemical Society, 2025) Rodrigo Villagomez; Maribel Lozano; Yonny Flores; Yasufumi Kobayashi; Yasunari Fujita; Giovanna R. Almanza
Quinoa saponins (SAPs) are key secondary metabolites occurring as complex mixtures mainly in the seed coat of <i>Chenopodium quinoa</i> Willd. Although traditionally removed due to their bitter taste and potential toxicity, quinoa SAPs display diverse biological activities, including anti-inflammatory, hypocholesterolemic, antifungal, molluscicidal, hemolytic, and cytotoxic effects, that support their potential applications in pharmaceuticals, functional foods, cosmetics, and biopesticides. Their amphiphilic nature also enables their use as natural emulsifiers. This review (1981-2024) summarizes advances in analytical methodologies for quinoa SAPs, emphasizing that while GC-MS and LC-MS/MS are widely applied for profiling, full structural elucidation still requires isolation and analysis by NMR and MS. We discuss key considerations for quinoa SAPs identification using GC-MS, LC-MS/MS, and NMR. Quantification remains challenging and is often based on relative estimations, with afrosymmetric, UV-vis, and GC-MS methods being the most frequently employed, while HPLC-DAD, LC-MS, and GC-MS/MS offer greater sensitivity. Ultimately, the selection of the analytical method and standard critically determines accuracy.
CUANTIFICACIÓN DE SAPONINAS EN RESIDUOS DE QUINUA REAL CHENOPODIUM QUINOA WILLD
(Lund University, 2012) Maribel Lozano; Edgar Freddy Quisbert Ticona; Cristhian Carrasco; Yonny Flores; Giovanna R. Almanza
"En el presente trabajo se realizó la cuantificación del rendimiento de extractos y de saponinas en residuos de escarificado generados en empresas exportadoras de quinua de los departamentos de La Paz, Oruro y Potosí, determinándose que los rendimientos de extracción varían desde 36,0 % hasta 39,4 % p/p, mientras que el porcentaje de saponinas en el extracto varía desde 47,3 % hasta 56,2 % y de saponinas en el mojuelo desde 17,3 % hasta 22,1 %. Adicionalmente, se optimizó un método de extracción de saponinas por maceración con mezclas hidroalcohólicas, considerando los siguientes parámetros: Relación masa/volumen de extracción; tiempo de extracción y relación porcentual EtOH/H2O (v/v), determinándose que la mejor relación m/v de extracción es 1/9. El tiempo de extracción óptimo es de 72 h y la mejor mezcla de extracción es con 50/50 EtOH/H2O. El porcentaje de saponinas se determinó utilizando los métodos de Espuma, Espectrofotométrico UV y por cromatografía HPLC, observándose que no hay grandes diferencias entre los 3 métodos aunque el método HPLC es el que tiene menos error y debería utilizarse como método de control para los otros métodos que son más baratos. Además, es muy importante utilizar como muestra de referencia un estándar de saponinas de quinua en todos los métodos."
DETERMINACIÓN DE PARÁMETROS DE SECADO POR ASPERSIÓN PARA LA OBTENCIÓN DE EXTRACTO SECO RICO EN SAPONINAS DE RESIDUOS DE ESCARIFICADO DE QUINUA
(2022) Silvia E. Ramos; Abel Gutiérrez; Yonny Flores; Maribel Lozano; Lizzet Chura; Rocío Mamani; Heriberto Castañeta; Giovanna R. Almanza; Lizzet Chura; Laboratorio de Fisicoquímica, Instituto de Investigaciones Químicas IIQ, Carrera de Ciencias Químicas, Facultad de Ciencias Puras y Naturales FCPN, Universidad Mayor de San Andrés UMSA, P.O. Box 303, Calle Andrés Bello s/n, Ciudad Universitaria Cota Cota, La Paz-Bolivia
Los residuos de escarificado de quinua se generan en gran cantidad en Bolivia y tienen un alto contenido de saponinas, compuestos con diversas propiedades que les dan un potencial uso en cosmética, agricultura, salud y otros. Por esta razón, es importante contar con métodos para obtener extractos secos ricos en saponinas a partir de estos residuos. En el presente trabajo, se han determinado los parámetros para el secado por aspersión de un extracto acuoso residual de un proceso de extracción hidroalcohólico EtOH:H2O (50:50) por 72 h, seguido de una eliminación del EtOH por rotaevaporación. Para esto, se utilizó un diseño experimental factorial 23, tomando como variables independientes: la concentración del extracto acuoso residual, la temperatura de secado y la velocidad del flujo de aire. Se determinó que las variables significativas para obtener un mayor rendimiento de extracción en el proceso de secado por aspersión son: la temperatura de secado (100°C) y la velocidad del flujo del aire (4192 rpm), con un flujo de alimentación de 8.0 mL/min. El producto seco obtenido tiene un rendimiento de 27.6% respecto a los residuos de quinua y 68.73 % de saponinas. La técnica de secado por aspersión presentó algunas ventajas respecto a la técnica de secado por liofilización, como el mayor porcentaje de saponinas en el extracto seco obtenido y el menor tiempo empleado para el secado.
DETERMINACIÓN DEL CONTENIDO FENÓLICO, Y EVALUACIÓN DE LA ACTIVIDAD ANTITIROSINASA, Y DE LOS ÍNDICES ANTIOXIDANTES DE CUATRO VARIEDADES DE QUINOA BOLIVIANA.
(2020) Alejandra Navia; Peggy Ormachea; Lily Salcedo; Maribel Lozano; Santiago Tarqui; Yonny Flores; Giovanna R. Almanza; Giovanna R Almanza
Four varieties of Bolivian quinoa (QJG Quinoa Jacha Grano, QRB Quinoa Real Blanca, QRN Quinoa Real Negra and QRR Quinoa Real Roja) have been studied in order to valorize them through the establishment of the phenolic contents and consequently by their antioxidant indexes. In addition, and in this pathway, the antityrosinase activity of the four varieties was measured. One important quinoa-endemic glycosylated flavonoid, mauritianin 1 (Kaempferol-3-O-(2,6-di-O--ramnopyranosyl--galactopyranoside) was isolated, and identified by cromatographic and spectroscopic methods and it was quantified. The four quinoa samples were treated by means of solid-liquid extractions with hydro-alcoholic 8:2 solvents. Quantifications and evaluations were done in the samples of the four varieties of quinoa and in phenolic rich fractions from the extract of QJG, and in compound 1, coming from the QJG extract. In a series of in vitro tests, antioxidant indexes, by means of the total phenolic content and ABTS methods, and antityrosinase activities, by using the fungal tyrosinase method, of phenolic rich fractions and of the pure compound 1 were evaluated, 1 showed an important antityrosinase activity (74.73% I at 1.67 mg/mL) and antioxidant (826.68 mg GAE/g and 1141.38 M Trolox/g), as well as the phenolic rich fraction from the extract of QJG named as EEW-1 that showed 69.89% I of the enzyme tyrosinase and significant antioxidant activity (246.08 mg GAE/g and 569.21 uM trolox/g), suggesting that these products could have a potential application in dermatology, cosmetics and food processing.
Effect of saponins of Chenopodium quinoa Willd agains the phytopatogenic fungus Cercospora beticola Sacc.
(2016) Rinel Apaza; Smeltekop Hugh; Yonny Flores; Giovanna R. Almanza; Lily Salcedo
ESTUDIO FITOQUIMICO Y ESPECTROSCOPICO PRELIMINAR DE CINCO PLANTAS MEDICINALES DE CARMEN PAMPA (COROICO) BOLIVIA
(Universidad Autónoma del Estado de México, 2012) Ángela J. San Martin; Esther Villanueva; Arnold Tito Cruz; Desiderio Flores; Rubén D. Gomez; Giovanna R. Almanza; Yonny Flores
"Five plant species widely distributed and with traditional medicinal use in the community of Carmen Pampa, Rubus boliviensis (khari-khari), Castillejo arvensis (vira-vira), Baccharis genistelloides ssp crispa (charara), Liabum hastifolium (toco-toco) and Acmella ciliata (laili-laili), were subjected to a preliminary phytochemical and spectroscopic study in order to select promising plant species for fiirther studies. In the preliminary phytochemical study it was determined that the plant species studied have mainly phenolic compounds, tannins, triterpenes or steroids. Additionally the species B. genistelloides presents flavonoids and A. ciliata presents coumarins plus some alkaloids in the flowers. The spectroscopic study shows that all the extracts have a certain absorbance in the UVB and UVA region, but this is not comparable to the photoprotective known compounds as oxybenzone, or plant species studied for their photoprotective effect as Baccharis papillosa. However, the extract of major interest from this point of view is the extract of L. hastifolium (toco -toco). To complete the information, a deep literatee review was done showing that R. boliviensis (khari-khari) and C. arvensis (vira-vira) have no previous chemical and biological studies, while B. genistelloides shows many bibliographic antecedents being currently used in commercial producís in countries such as Brazil and Peru. Moreover L. hastifolium (toco-toco) has studies showing leishmanicidal activity which correlates with its traditional use for the treatment of wounds and has no chemical background so it was selected for further studies. The species B. genistelloides also shows interesting traditional and scientific background, but it was full studied and it is advisable to use the existing studies in the promotion of sustainable products with economic potential. Finally we also recommend develop studies on R. boliviensis because there are important chemical and pharmacological results in other species of genus Rubus."
FLAVONOIDES DE BACCHARIS BOLIVIENSIS
(2012) Alberto Calle; Jimena Yupanqui; Yonny Flores; Giovanna R. Almanza
NMR Mestrenova, short manual for beginners
(Universidad Autónoma del Estado de México, 2017) José A. Bravo; José L. Vila; Yonny Flores
"This short review presents in a very compact manner the few steps to manipulate 1D and consequently 2D NMR spectra ge nerated in the MestReNova ® system. The manual explains how easily we can transform spectral data into different expositive manners. In this sense , we started showing the way to put together 13 C and DEPT spectra in the same page with peaks aligned . The way to write, erase or edit the name of spectra is also explained. The way to manipulate 1 H NMR spectra is exposed. Th e treatment and development of most common use 2D spectra is detailed; this includes COSY/NOESY spectra as well as HSQC/HMBC spectra"
OLEANANE-TYPE TRITERPENES AND DERIVATIVES FROM SEED COAT OF BOLIVIAN CHENOPODIUM QUINOA GENOTYPE “SALAR”
(Lund University, 2005) Yonny Flores; Carlos Barrera-Díaz; Fidel Garay; Osmar Colque; Olov Sterner; Giovanna R. Almanza
"Bolivia is the first world exporter of quinoa (Chenopodium quinoa Willd) genotype “salar”. In its natural state quinoa has a coating of bitter-tasting (saponins), making it essentially unpalatable. Most of quinoa exported from Bolivia has been processed to remove this coating. These seed coat residues contain a high level of oleanane-type saponins. From those residues two oleanane-type triterpenes were found as the major sapogenins and their structures were identified as: oleanolic acid and deoxyphytolaccagenic acid in base of NMR means. Furthermore, two derivatives of oleanolic acid were obtained: 28-Omethyl and 3-O-acetyloleanolic acid. The importance of oleanolic acid content in this industrial residue is discussed."
PHENOLIC COMPOUNDS FROM BACCHARIS PAPILLOSA SUBSP. PAPILLOSA
(Universidad Autónoma del Estado de México, 2009) Zilma Escobar; Yonny Flores; Leslie Tejeda; Juan Alvarado; Olov Sterner; Giovanna R. Almanza
"Cuatro compuestos fenólicos fueron aislados Ermanine 1, Isokamferine 2, Drupanine 3 and 5,7,5 ,4 - tetrahidroxi- 3-metoxiflavona 4 a partir de las hojas secas de Baccharis papillosa subsp. papillosa. Sus estructuras fueron determinadas por métodos espectroscópicos y comparados con datos bibliográficos. El material vegetal fue colectado en dos estaciones; invierno y verano, en ambos casos fueron determinados los mismos compuestos pero con diferentes rendimientos, incrementandose la cantidad de los compuestos 2, 3 y 4 en verano. Además, se evaluó la actividad antioxidante de cada compuesto puro mediante dos métodos: ABTS y FRAP, determinandose una potente actividad para el compuesto 4, una significante actividad para el compuesto 2 y una débil actividad para los compuestos 1 y 3."
Quantification and in vitro photo-protective studies of phenolic compounds from Baccharis papillosa Rusby
(2022) Alberto Calle; Cecilia K. Curi-Borda; Cervando Gutiérrez; Lily Salcedo-Ortiz; Yonny Flores; Giovanna R. Almanza
Context: The ethanolic extract of the leaves from Baccharis papillosa, a plant used in Bolivian folk medicine, presents high UVB/UVA absorption spectrum, and therefore, it could have photo-protective potential. Aims: To isolate, identify and quantify the compounds of an enriched extract in phenolic compounds obtained from the ethanolic extract of Baccharis papillosa in different seasons and geographical altitudes, and evaluate its photo-protective potential. Methods: The enriched extract in phenolic compounds was submitted to phytochemical analysis for compound isolation. The enriched extract and isolated compounds were identified by NMR, and monitored by HPLC and spectroscopic methods. The enriched extract with photo-protective potential was analyzed to determine its Spectroscopic Sun Protection Factor (SSPF), its Broad Spectrum Index (BSI) and its photo-protective activity on Escherichia coli bacteria. Results: Six flavonoids and two cinnamic acid derivatives were isolated and identified. Four of them are reported in B. papillosa for the first time in this study. The highest concentration of total flavonoids was observed in spring and at the highest altitude. The major compound, drupanin, was the main responsible of the high UVB (290-320 nm) absorption spectrum. The high presence of flavonoids in the extract explains the absorption spectrum in the UVA (320-400 nm) region. Conclusions: The phenolic compounds enriched extract has photo-protective properties comparable to standard commercial synthetic sunscreens and presents an attractive BSI.
SECONDARY METABOLITES FROM CAESALPINIA PLUVIOSA
(Universidad Autónoma del Estado de México, 2006) Yonny Flores; José Vila; Giovanna R. Almanza
"Two phenolic compounds, ethyl gallate and rhuschalcone VI, together with lupeol, betulinic acid and stigmasterol were isolated from the stem bark of Caesalpinia pluviosa D.C. Their structures were determined by spectroscopic means mainly by NMR experiments, completing all the NMR assignments of phenolic compounds. In addition, the extracts and pure compounds were evaluated against the bacteria Staphylococcus aureus, HPIA test and the antimalarial in vitro assay against Plasmodium falciparum, determining that CH2Cl2 extract and rhuschalcone VI showed good activity in the antibacterial and HPIA tests."