ABSTRACT
Objective: To analyze the contents of eight saccharides in unprocessed and processed Rehmannia glutinosa by HPLC and to investigate the impacts of processing time on saccharides in R. glutinosa. Methods: HPLC conditions were as follows: Prevail Carbohydrate ES column (250 mm × 4.6 mm, 5 μm), flow rate of 0.8 mL/min, ELSD detector, acetonitrile as mobile A and water as mobile B for gradient elution. Results: Fructose, glucose, surcrose, melibiose, raffinose, manninotriose, stachyose, and verbascose were separated with good linear relationships within their corresponding concentration ranges, the r values were within 0.998 4-0.999 7; the average recovery was 97.5%-103.2%. The content analysis at different processing time points showed that surcrose, raffinose, stachyose, and verbascose exhibited decreasing trend during processing, while fructose, glucose, melibiose, and manninotriose exhibited significantly increasing trend. Conclusion: The proportions of saccharides in unprocessed and processed R. glutinosa are significantly different, and the results of this study could provide the data support for revealing the processing mechanism of R. glutinosa.
ABSTRACT
This study was aimed to explore the impact of activated carbon adsorption modified by different concentrations of nitric acid and ammonia,in order to examine the impact on adsorption of mannotriose by modified activated carbon.The activated carbon was processed by different concentrations of nitric acid and ammonia.And then,the adsorption capacity of benzene,iodine,methylene blue and the purification effects on mannotriose were measured.The results showed that the active carbon modified by nitric acid and ammonia had some changes of adsorptions for methylene blue,iodine and benzene.The purification effect of mannotriose with nitric acid-modified activated carbon was declined.The purification effect of mannotriose with ammonia-modified activated carbon was increased.It was concluded that the pore structure of activated carbon had been changed by nitric acid and ammonia.The adsorption capacity of nitric acid modified active carbon to mannotriose was declined.However,the adsorption capacity of ammonia modified active carbon to mannotriose was increased.It showed that ammonia modified active carbon was suitable for the purification of mannotriose.And the adsorption capacity of iodine reflected the adsorption capacity of mannotriose by active carbon.