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ABSTRACT: The aims of this study were to establish the antimicrobial potential of Hofmeisteria schaffneri essential oil and its chemical composition.
The essential oils of Hofmeisteria schaffneri harvested at flowering (batches I and IV) and non-flowering (batches II and III) seasons were prepared by hydrodistillation and analysed by GC and GC-MS. The aqueous and organic (CH(2) Cl(2) -MeOH 1 : 1) extracts were prepared by using infusion and maceration techniques, respectively. The in-vitro antimicrobial activity of the preparations and compounds against Candida albicans and some bacteria (Gram-negative and Gram-positive) was assessed using the broth dilution method in 96-microplate wells.
Forty-four compounds, representing ∼90% of the total constituents, were identified in the essential oil of Hofmeisteria schaffneri collected in flowering (batches I and IV) and non-flowering (batches II and III) seasons. In all cases, several thymol analogues were the major components of the oils (∼65%); some small differences in the relative proportions of these constituents were observed. The infusion exhibited an antibacterial activity against Staphylococcus aureus and Bacillus subtilis, with a MIC value of 64 µg/ml in each case. The essential oil batches were active against Staphylococcus aureus, with MIC ranging from 48 to 192 µg/ml. They were, however, inactive against Gram-negative bacteria, including Pseudomonas aeruginosa, Escherichia coli and Salmonella typhi (MIC > 1024 µg/ml). On the other hand, the infusion of the plant as well as the oil from batch I displayed anti-Candida albicans activity, with MIC of 128 and 192 µg/ml, respectively. Finally, the organic extract did not displayed significant activity against the tested microorganisms (MIC ≥ 1024 µg/ml). Some of the compounds isolated from the plant were also tested. Compounds 8 and 38, which were present in the essential oils, displayed the best antibacterial effect against Gram-positive bacteria (MIC ranging between 32 and 64 µg/ml). Compounds 6 (present in the infusion) and 10 (present in all preparations) showed higher activity against the yeast (MIC = 128 µg/ml) than the remaining compounds, with MIC values ranging from 256 to 512 µg/ml.
The composition and antimicrobial activity of the oils changed slightly from flowering to non-flowering seasons. The results of the present investigation provide in-vitro scientific support for the use of the plant against skin infections in Mexican folk medicine.
The Journal of pharmacy and pharmacology. 04/2011; 63(4):579-86.
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ABSTRACT: In contrast to the hydrolysis of reserve carbohydrates in most plant-derived alcoholic beverage processes carried out with enzymes, agave fructans in tequila production have traditionally been transformed to fermentable sugars through acid thermal hydrolysis. Experiments at the bench scale demonstrated that the extraction and hydrolysis of agave fructans can be carried out continuously using commercial inulinases in a countercurrent extraction process with shredded agave fibers. Difficulties in the temperature control of large extraction diffusers did not allow the scaling up of this procedure. Nevertheless, batch enzymatic hydrolysis of agave extracts obtained in diffusers operating at 60 and 90 degrees C was studied at the laboratory and industrial levels. The effects of the enzymatic process on some tequila congeners were studied, demonstrating that although a short thermal treatment is essential for the development of tequila's organoleptic characteristics, the fructan hydrolysis can be performed with enzymes without major modifications in the flavor or aroma, as determined by a plant sensory panel and corroborated by the analysis of tequila congeners.
Journal of Agricultural and Food Chemistry 07/2009; 57(12):5578-85. · 2.82 Impact Factor
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ABSTRACT: Solid phase microextraction and capillary gas chromatography-mass spectrometry were used for the determination of seven terpenes in tequila. The method was selected based on the following parameters: coating selection (PA, PDMS, CW/DVB, and PDMS/DVB), extraction temperature, addition of salt, and extraction time profile. The extraction conditions were: PDMS/DVB fiber, Headspace, 100% NaCl, 25 degrees C extraction temperature, 30 min extraction time and stirring at 1200 rpm. The calibration curves (50-1000 ng/ml) for the terpenes followed linear relationships with correlation coefficients (r) greater than 0.99, except for trans,trans-farnesol (r = 0.98). RSD values were smaller than 10% confirmed that the technique was precise. Samples from 18 different trade brands of "Aged" tequila analyzed with the developed method showed the same terpenes in different concentrations. The analytical procedure used is selective, robust (more than 100 analyses with the same fiber), fast and of low-cost.
Journal of Chromatography 12/2006; 1134(1-2):291-7. · 4.53 Impact Factor
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ABSTRACT: The aim of this work was to develop an analytical method by High Temperature Capillary Gas Chromatography (HT-CGC) to characterize and identify the presence of tzauhtli, orchid mucilage, in works of art. During the pre-Hispanic and colonial period, tzauhtli was used as an adhesive for paper and feathers, as well as paint binder, and was one of the components of the paste used to model corn stalk sculptures. The mucilage was extracted with hot water from orchid bulbs (Bletia campanulata) and lyophilized. The free sugars from the mucilage were analyzed by CGC after derivatization. The polysaccharide of the mucilage was characterized after its partial acid hydrolysis by HT-CGC analysis of the oligosaccharides obtained. The proposed chromatographic method allows the identification of different mucilages in works of art. This contribution is the first report of the oligosaccharides from the hydrolysis of the mucilage extracted from orchid bulbs (Bletia campanulata).
Journal of High Resolution Chromatography 04/2005; 18(11):713 - 717.
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ABSTRACT: Steam distillation (SD) extraction-solid-phase microextraction coupled to GC-MS was developed for the determination of terpenes and Bligh-Dyer extraction-derivatization coupled with GC for the determination of fatty acids such as ethyl esters were used. It was found that the three different Agave species have the same profile of fatty acids; the quantity of these compounds is different in each Agave variety. On the other hand, different terpenes were identified in the three Agave plants studied: nine in A. salmiana, eight in A. angustifolia and 32 in A. tequilana Weber var. azul.
Journal of Chromatography 03/2004; 1027(1-2):131-6. · 4.53 Impact Factor
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ABSTRACT: Debido a sus propiedades carcinogénicas y mutagénicas los hidrocarburos aromáticos policíclicos (HAP) han sido estudiados ampliamente. La determinación de los HAP en tejidos de organismos marinos requiere de métodos adecuados para su extracción, identificación y cuantificación, ya que este tipo de matrices contiene mezclas complejas de compuestos de naturaleza lipofílica que interfieren en el análisis de los HAP. El procedimiento estándar para la determinación de estos compuestos consume mucho tiempo principalmente el paso de limpieza antes del análisis por CG y/o CG-EM. En este estudio se compara el procedimiento tradicional de purificación por cromatografía en columna abierta con la extracción en fase sólida (EFS) en cartuchos para la determinación de HAP en organismos marinos por cromatografía de gases (CG). El método propuesto se aplicó a tejidos de organismos marinos (pescado, camarón y ostión). Las muestras de tejido liofilizado se saponificaron con KOH en metanol y se extrajeron con hexano. El extracto así obtenido se purificó por ambos procedimientos. El método de purificación tradicional se llevó a cabo en columnas empacadas con gel de sílice, alúmina, sulfato de sodio anhidro y cobre activado. La EFS se realizó en cartuchos comerciales de aminopropil (LC-NH2) y gel de sílice (Spe-ed Silica-gel). Los extractos que se obtuvieron se analizaron por CG y los resultados se confirmaron por CG-EM. La identificación de los HAP se realizó comparando los tiempos de retención con estándares externos y la cuantificación a través del factor de respuesta calculado para cada uno de los HAP. Los porcentajes de recuperación de los HAP se estimaron utilizando tejido de pescado fortificado. Los resultados que se generaron en ambos procedimientos fueron comparados. El porcentaje de recuperación de los HAP en la fracción aromática fue 42.90 ± 2.80 % utilizando el procedimiento de purificación por cromatografía en columna, 56.87 ± 6.23 % para LC-NH2 y 58.56 ± 4.89 % en sílica. El límite de detección del m
Revista Internacional de Contaminación Ambiental. 01/2003;
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ABSTRACT: Por medio de la cromotagrafia en fase de vapor se analizaron 37 muestras de tíner, obtenidas de diversos establecimientos comerciales tanto del Distrito Federal como de algunos Estados de la República Mexicana. Se notó gran variabilidad en la formulación tanto en la cantidad de componentes (entre 7 y 35) como en su concentración, indicando que no existe una norma que determine las características del producto. El tolueno fue el único que se observó en todas las muestras y su concentración varió de 7 a 77 %. El porcentaje de frecuencia de otros agentes químicos como metanol, hcxano, acetona y benceno fue de 90,87,87 y 68%, respectivjunente, y sus concentraciones variaron desde 0.02 a 60.0%. En el 98% de las muestras hubo compuestos no identificados en cantidades de 0.02 a 38.20%. La presencia del tolueno y su alta concentración en todos los casos, posiblemente sea el factor principal causante de las alteraciones psíquicas, neurofisiológicas y conductuales, así como de los efectos tóxicos descritos en farmacodependientes y en trabajadores expuestos al tíner, aunque no se descarta la participación de otras sustancias en la producción de los mismos.
Revista Internacional de Contaminación Ambiental. 01/1988;
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ABSTRACT: Steam distillation (SD) extraction–solid-phase microextraction coupled to GC–MS was developed for the determination of terpenes and Bligh–Dyer extraction–derivatization coupled with GC for the determination of fatty acids such as ethyl esters were used. It was found that the three different Agave species have the same profile of fatty acids; the quantity of these compounds is different in each Agave variety. On the other hand, different terpenes were identified in the three Agave plants studied: nine in A. salmiana, eight in A. angustifolia and 32 in A. tequilana Weber var. azul.
Journal of Chromatography A.
