Permeability has an important effect on drug absorption. In this study, the effect of different concentrations of sodium sulfobutyl ether-β-cyclodextrin (SBE-β-CD) on the absorption of ranitidine was investigated to examine the mechanism of permeability changes. The results of parallel artificial membrane permeability assay (PAMPA) showed that increasing the concentration of sodium sulfobutyl ether-β-cyclodextrin, 0, 0.12% (w/v), 0.36% (w/v) and 3.6% (w/v), respectively, the apparent permeability coefficient of ranitidine decreased to 4.62×10-5 , 4.5×10-5 , 3.61×10-5 and 1.08×10-5 in Caco-2 cells, respectively. The same results were obtained from oral pharmacokinetic study in rats; Further studies indicated that SBE-β-CD significantly increased the zeta potential of ranitidine. SBE-β-CD interacted with ranitidine charges to form a complex that reduced ranitidine permeability, and SBE-β-CD should be chosen with caution for drugs with poor permeability.

Intercropping significantly improves land use efficiency and soil fertility. This study examines the impact of three cultivation systems (monoculture sugarcane, peanut-sugarcane and soybean-sugarcane intercropping) on soil properties and diazotrophs. Sugarcane rhizosphere soil was sampled from the farmers’ field. Soil properties and nifH gene abundance were analyzed by high throughput sequencing. Moreover, a total of 436,458 nifH gene sequences were obtained and classified into the 3201 unique operational taxonomic units (OTUs). Maximum unique OTUs resulted with soybean-sugarcane intercropping (<375). The dominant groups across all cultivation were Alpha-proteobacteria and Beta-proteobacteria. On the basis of microbial community structure, intercropping systems were more diverse than monoculture sugarcane. In the genus level, Bradyrhizobium, Burkholderia, Pelomonas, and Sphingomonas were predominant in the intercropping systems. Moreover, diazotrophic bacterial communities of these cultivation systems were positively correlated to the soil pH and soil enzyme protease. Moreover, low available P recovered from intercropping system showed a strong correlation with higher nutrient uptake activity of soil microbes. Based on the results, our investigation concluded that intercropping system caused a positive effect on the growth of diazotrophic bacterial communities and it might boost the soil fertility and this kind of study helps to develop an eco-friendly technology for sustainable sugarcane production.