Abstract The effects of ultrasound-assisted extraction (UAE) at different ultrasound power densities (UPDs; 40, 80, and 120 mW/mL) and solid:liquid (S:L) ratio (1:2, 1:3, and 1:6) on the extraction of carbohydrates from Agave tequilana plant of different ages were evaluated. Extracts obtained (6- and 7-year-old plant) were analyzed in the yield of carbohydrates (YC), fructan (FRU) content, simple sugars, fructan profile and the average degree of polymerization (DPn). UPD, S:L ratio, and plant age all affected YC, FRU, and DPn. Maximum YC and FRU were obtained from the older agave with UPD and S:L ratio of 120 mW/mL and 1:6, respectively; while glucose, fructose, and sucrose were highly released from the younger plant. Agave of 7-year-old presented the highest DPn. Fructan degradation occurred at high UPD, increasing the simple sugars and decreasing the DPn. Thermal-traditional extraction without sonication caused more fructan degradation; and overall, ultrasound enhanced fructan extraction and minimized fructan damage, representing a technological alternative for fructan extraction from agave.

Abstract: Infectious diseases remain a public health problem that is exacerbated by the presence of resistant organisms leading to development of novel drugs. Study of pharmacological proteins from natural sources recently emerged. In this research extraction of proteins from gel of Aloe vera and antimicrobial evaluation were done. Protein extracts from Aloe vera were obtained by two methods: extract 1(EP1) by precipitation with (NH4)2SO4 and (EP2) by phenol extraction. The yield for method 2 (0.33 % recovery). Analysis by mass spectrometry of EP1 identified with a high degree of confidence, peptide 5 and 31-kDa protein, whose identity has been associated with the glycoproteins of Arabidopsis thaliana. EP2 exhibited inhibitory activity against Staphylococcus aureus and Candida albicans. A. vera extract comprises a promising source of protein with anti-S. aureus and anti-C. albicans activity.

Resumen: Las enfermedades infecciosas son un problema de Salud Pública que se agrava con microorganismos resistentes. Esto conduce al desarrollo de nuevos fármacos. Recientemente surgió el estudio de actividades farmacológicas de proteínas de fuentes naturales. En esta investigación se realizó la extracción de proteínas del gel de Aloe vera y su evaluación antimicrobiana. Se obtuvieron extractos proteicos de A. vera por dos métodos: Extracto 1 (EP1) precipitación con (NH4)2SO4 y extracto 2 (EP2) extracción con fenol. El rendimiento para el método 2 (0.33 % recuperación). Análisis por espectrometría de masas EP1 permitió identificar un péptido y una proteína de 5 y 31 kDa, relacionada con glicoproteínas de Arabidopsis thaliana. EP2 mostró actividad contra Staphyllococcus aureus y Candida albicans. A. vera es una fuente prometedora de proteínas con actividad anti-S. aureus y -C. albicans.

The aim of this work was the evaluation of the antimicrobial and cytotoxic activity of methanolic extract of crude Leucophyllum frutescens Var. (Berl) I. M. Johnst ("Texas Sage", "Texas Ranger" or "Silverleaf") against Staphylococcus aureus strain from a clinical isolate. The study of the antimicrobial activity showed that the extract has activity at three evaluated concentrations 1000, 500 and 250 μg/mL, with a minimum inhibitory concentration of 25.4 μg/mL. In the Artemia salina assay, the extract showed toxicity with a DL50 196.37 μg/mL and was active on VERO cell lines having an IC50 of 58.0 μg/mL. These findings contribute to the scientific knowledge of medicinal plants in North of México with antibacterial properties.

El objetivo de este trabajo fue evaluar la actividad antimicrobiana y citotóxica del extracto metanólico crudo de Leucophyllum frutescens Var. (Berl) I.M. Johnst ("cenizo") contra la cepa de Staphylococcus aureus de un aislado clínico. El estudio de la actividad antimicrobiana demostró que el extracto de hojas de Leucophyllum frutescens presenta actividad en las tres concentraciones evaluadas 1000, 500 y 250 μg/mL, con una concentración mínima inhibitoria de 25.4 μg/mL. En el ensayo de Artemia salina, el extracto presentó toxicidad con una DL50 196.37 μg/mL y resultó activo sobre líneas celulares VERO encontrándose una IC50 de 58.0 μg/mL. Estos hallazgos contribuyen al conocimiento científico de las plantas medicinales del Norte de México con propiedades antibacterianas.