A b s t r a c tTwo hundred and fifty bacterial strains were isolated from pinyon rhizosphere and screened for biosurfactants production. Among them, six bacterial strains were selected for their potential to produce biosurfactants using two low cost wastes, crude glycerol and lactoserum, as raw material. Both wastes were useful for producing biosurfactants because of their high content in fat and carbohydrates. The six strains were identified by 16S rDNA with an identity percentage higher than 95%, three strains belonged to Enterobacter sp., Pseudomonas aeruginosa, Bacillus pumilus and Rhizobium sp. All strains assayed were able to grow and showed halos around the colonies as evidence of biosurfactants production on Cetyl Trimethyl Ammonium Bromide agar with crude glycerol and lactoserum as substrate. In a mineral salt liquid medium enriched with both wastes, the biosurfactants were produced and collected from free cell medium after 72 h incubation. The biosurfactants produced reduced the surface tension from 69 to 30 mN/m with an emulsification index of diesel at approximately 60%. The results suggest that biosurfactants produced by rhizosphere bacteria from pinyon have promising environmental applications. 184the lack of knowledge about the interaction between microbes and pinyon roots.Additionally, agro-industrial organic wastes has recently been used as substrate to cultivate BS due to its low cost and high availability (Cassidy and Hudak, 2001;Kitamoto et al., 2002; Abbasi et al., 2012;. It is well known that wastes from palm oil, canola oil, soybean, glycerol and buttermilk, may be used to achieve an increase in production of about ten times in the mass of BS produced higher than that obtained when the production media contain glucose as the carbon source (Makkar and Cameotra, 2002). For instance, Ron and Rosenberg (2001) and Abbasi et al. (2012) demonstrated that BS can be produced by P. aeruginosa through fruit wastes, waste vegetable oil and foodindustry wastes as the substrate. In this context, agroindustrial wastes generated in Chiapas are low cost raw material, renewable and abundant throughout the year, with a total generation of about 28-140 thousand tons per year. These wastes include crops and processing residues of corn, coffee, cocoa, mango, banana, oil palm and buttermilk (SAGARPA, 2007; Valdéz-Vázquez et al., 2010). Likewise, huge amounts of glycerol were generated from the biodiesel fuel production in Chiapas during a 5 years operation period and, because this crude glycerol is expensive to purify for use in other industries, it remains without any disposal method and becoming a significant environmental problem, but potentially valuable as substrate to produce BS.Hence, the isolation of bacteria strains from pinyon rhizosphere capable of biosurfactant production by using four agro-industrial wastes as substrate is of interest in commercial production. In the present study, the presence of potential biosurfactant producer bacteria was determined by the formation of a complex with CTAB w...

En la actualidad, los quesos crema producidos en las Regiones Costa, Selva y Norte del estado de Chiapas, son los de mayor comercialización. Estos quesos no son producidos en grandes escalas y son heterogéneos. Sin embargo, tienen buena aceptación entre los consumidores por sus características sensoriales que presentan. El propósito de este proyecto fue la caracterización de los quesos étnicos de Chiapas mediante análisis fisicoquímicos para verificar que éstos cumplieran con las normas NMX-F-092-1970 y NOM-243-SSA1-2010. Se llevó a cabo una recolección de muestras de queso crema que se elaboran en las diferentes regiones del Estado de Chiapas, se realizaron pruebas fisicoquímicas: pH, humedad, sólidos totales, grasa, proteína y cenizas, y se compararon con las normas.Los resultados indicaron que, a excepción del pH, los quesos tipo crema de las regiones Costa, Selva y Norte del Estado de Chiapas se encontraban dentro de las Normas Oficiales Mexicanas, y que la Región Costa fue la que presentó los mayores contenidos de cenizas (4.49 %), sin embargo, en relación a contenidos de grasa, sólidos totales, humedad y proteínas en las tres regiones son iguales, por lo que son quesos con valor nutrimental deseable.