RESUMEN
Although oilfields harbor a wide diversity of microorganisms with various metabolic potentials, our current knowledge about oil-degrading bacteria is limited because the vast majority of oil-degrading bacteria remain uncultured. In the present study, microbial communities in nine oil-contaminated soils collected from Daqing and Changqing, two of the largest oil fields in China, were characterized through highthroughput sequencing of 16S rRNA genes. Bacteria related to the phyla Proteobacteria and Actinobacteria were dominant in four and three samples, respectively. At the genus level, Alkanindiges, Arthrobacter, Pseudomonas, Mycobacterium, and Rhodococcus were frequently detected in nine soil samples. Many of the dominant genera were phylogenetically related to the known oil-degrading species. The correlation between physiochemical parameters within the microbial communities was also investigated. Canonical correspondence analysis revealed that soil moisture, nitrate, TOC, and pH had an important impact in shaping the microbial communities of the hydrocarbon-contaminated soil. This study provided an in-depth analysis of microbial communities in oilcontaminated soil and useful information for future bioremediation of oil contamination.
Asunto(s)
Bacterias/clasificación , Bacterias/genética , Biota , Petróleo/análisis , Microbiología del Suelo , Contaminantes del Suelo/análisis , Carbono/análisis , Fenómenos Químicos , China , Análisis por Conglomerados , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Concentración de Iones de Hidrógeno , Datos de Secuencia Molecular , Nitratos/análisis , Compuestos Orgánicos/análisis , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Suelo/químicaRESUMEN
OBJECTIVE: To study the formulation of Naoxuekang dispersible tablets. METHODS: The formulation was determined by pre-processing leech extractum prior to a series of experiments used to screen excipients like bulking agents and disintegrants and so on, and by adding disintegrants within and without. RESULTS: Microcrystalline cellulose was determined as the bulking agent, and carboxymethyl cellulose and low-substituted hydroxypropyl cellulose were determined as the disintegrants of Naoxuekang dispersible tablet formula. The average disintegration time and nitrogen content of one tablet were 52 seconds and 5.47 milligrams, respectively. Also disperse homogeneity, weight variation and microbial limit all met the requirements in Ch. P. CONCLUSION: The prepared Naoxuekang dispersible tablet is reasonable in formula, feasible in technology, which meets the quality standards.