ABSTRACT
Aims: To inhibit of bacterial growth of three important phyto-pathogenic bacteria: Erwinia carotovora, Clavibacter michiganensis sp. michiganensis and Xanthomonas axonopodis by cell-free extracts from submerged cultures of two strains of Enterococcus sp. was tested. Study Design: A complete randomized experimental design with factorial fix was used to evaluate the efficiency of growth inhibition against the phytopathogenic bacteria. Place and Duration of Study: Laboratory of Bioprocesses, Department of Food Science and Technology, School of Chemistry, Universidad Autonoma de Coahuila, Mexico, between December 2011 and July 2012. Methodology: Enterococci strains were isolated from goat milk, buttermilk and whey by typical microbiological procedures and primarily identified based on biochemical tests. Strains were subsequently activated in MRS broth and cells were separated by centrifugation and filtration. Cell-free extracts were tested against plant pathogenic bacteria to determine their growth inhibition potential. Results: Strains of Enterococcus MII-1 and MIV-2 were able to inhibit the growth of three pathogenic bacteria, demonstrating to be an attractive alternative for biological control assays. Conclusion: The cell-free extracts of Enterococcus spp. show inhibition potential to inhibit phytopathogenic bacteria that cause diseases in horticultural crops. Further studies are needed to completely evidence the high potential of use of cell-free extracts from Enterococcus MII-1 and MIV-2.
ABSTRACT
La ciudad de León cuenta con 500 empresas de curtiduría y 9 dedicadas al procesamiento del sebo cuyos subproductos (descarne) son desechos que se vierten al medio ambiente en grandes cantidades, ya que no representan un interés para su procesamiento y comercialización, lo que ha causado diversos problemas de contaminación en las zonas habitacionales circundantes por el vertido de aguas residuales, residuos sólidos y emisiones atmosféricas. El impacto al medio se puede considerar como adverso, directo y temporal; reversible, pero con un alto costo económico, lo que implica la necesidad de establecer medidas preventivas de control y mitigación. En el presente estudio se describen las etapas delproceso, las buenas y malas prácticas, los procedimientos estándares de operación y los impactos al medio ambiente originados por el inadecuado manejo de los residuos de las industrias sebaderas. Los resultados muestran que el 80 por ciento de las empresas procesadoras carece de sistemas de almacenamiento adecuado y no poseen sistemas de control ambiental. De igual manera, la mayoría de los operarios no cuenta con equipos de protección personal y no existe un adecuado manejo de sustancias utilizadas en los procesos, lo que incrementa el riesgo de accidentes laborales.
The city of León has 500 tannery companies and nine work in fat processing, whose by-product waste (rawhide) is dumped to the environment in tons because there is no interest in processing and commercializing this substance. This situation has caused several contamination problems in surrounding residential areas because ofthe discharge of wastewater, solid waste, and atmospheric emissions. Impact on environment can be considered as adverse, direct and temporal, as well reversible, but excessively expensive, which involvesthe need of established preventive measures of control and mitigation.The present study describes the different stages of the process, goodand bad practices, standard operational procedures, and environmentalimpacts due to the inadequate handling of waste by these companies. Results show that 80 percent of the processing companies lack appropriate storage systems and do not have an environmental control system. Additionally, most of the operators do not have personal protective equipment and there is not a proper handling of the substances used in processes; this increases the risk of work-related accidents.