The processing of Mexican limes generates great amounts of peel as a by-product. Lime peel is mainly rich in the flavonoid hesperidin, whose bioactivity is oriented mainly to cardiovascular diseases and cancer. The purpose of this work was to develop a green process for the extraction and purification of hesperidin from Mexican lime peel. The extraction of hesperidin was investigated on a laboratory scale by varying the solvent composition and the solid-to-solvent ratio, and then scaling this process (volume: 20 L). Next, a purification process using adsorption resins was assessed: first through static tests to determine the adsorption efficiency with two resins (FPX66, EXA118), and then on a packed column with 80 mL of resin at 25 °C. Lab-scale extraction showed that the best conditions were a solid-to-solvent ratio of 0.33 g/mL and 60% ethanol. After using these conditions at pilot scale and concentrating the solution, the hesperidin content of the extract was 0.303 mg/mL. Through static tests, higher adsorption efficiencies were achieved with the EXA-118 resin and diluted extract (4:6 ratio with 10% dimethylsulfoxide, (DMSO)). Finally, the purification process on a packed column from the diluted extract (hesperidin concentration of 0.109 mg/mL) had a mean recovery efficiency of almost 90%.

Physicochemical quality of tequila during barrel maturation. A preliminary study Calidad fisicoquímica del tequila durante su maduración en barrica. Un estudio preliminar Silver Tequila 100% agave was aged in new oak barrels from four French regions. The evolution of physicochemical parameters regulated by Official Mexican Standard, as well as color, turbidity, total acidity and pH were assayed during 34 weeks of maturation. Analysis of variance (ANOVA) showed significant differences between barrel origin on furan-2-carboxaldehyde, dry extract, color and turbidity; and throughout maturation time on all evaluated parameters, except for total acidity, ethanol, and butan-2-ol. The principal component analysis (PCA) made it possible to separate three different groups corresponding to Silver (S), Aged (A), and tequilas during ripening transition (G), as well as to describe an evolution in two steps. Finally, general discriminant analysis (GDA) made it possible to classify correctly 69% of the samples according to barrel origin and 100% of the samples as G and A tequilas.

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The aim of this work was to evaluate a method that enriches the phenolic content in the essential oil of oregano, by obtaining high and constant phenolic concentrations. By means of extractive techniques such as fractional distillation, it was possible to concentrate thymol and carvacrol, as high as 74% in one essential oil fraction. In addition, the influence of the source region of the oregano on the phenolic content in the essential oil obtained by fractional hydrodistillation was also investigated; however, no significant effect was found (P > 0.05) based on source region. It may be considered that the fractional hydrodistillation method standardizes the phenolic content in essential oil composition regardless of the source of the spice. In this way, this method enriches phenolic content and reduces the effect of variable environmental factors on the quality of essential oils of oreganos from three different Mexican states. PRACTICAL APPLICATIONS The present investigation was carried out to improve the traditional extraction method for essential oils. With a few modifications, this method allows the fractionation of oregano essential oil in a 50:50 ratio, obtaining two fractions with high phenolic content; phenols are responsible for microbicide properties of the essential oil of oregano. This is an important step, considering the variability in phenolic content found in this spice, and because almost all of the harvested oreganos in Mexico contain a 45–50% average phenolic content. This method is attractive because it enriches the phenolic content in the essential oil and reduces environmental factors that affect oregano's essential oil, thus improving the quality of the essential oil of oregano. The contributions of the present work are to increase knowledge in the field of aromatic herbs, to enhance the economic advantages of Mexican oregano and to propose alternative applications for use, such as novel microbicide ingredients in the development of natural food products.

The effect of elicitation in butterhead lettuce on carotenoid and polyphenol metabolism was evaluated. Different concentrations of arachidonic acid (AA), salicylic acid (SA), methyl jasmonate (MJ) (15, 45, and 90 μM) and Harpin protein (HP) (30, 60, and 120 mg/L) were applied on red and green butterhead lettuces. Total phenolic and flavonoid content were incremented by MJ (90 μM) in green and red lettuce. Carotenoids were increased in red lettuce (AA; 45 μM). Green lettuce modifies their phenolic acid profile after elicitation with AA and MJ; meanwhile, red lettuce incremented mainly in hydroxycinnamic acids and flavonols, MJ being the elicitor with the highest effect. There was an impact on secondary metabolite enzyme gene transcript concentration. Phenylalanine ammonia-lyase (PAL) and lycopene beta cyclase (LBC) increased in both varieties after elicitation. A relationship between phytochemical increase and the activation of the metabolic pathways after elicitation in butterhead lettuce was observed.