Preparation And Performance Evaluation Of Disintegrant For Straw Holocellulose

The chemical compositions of crop straw mainly consists of lignin,cellulose and hemicellulose,which interweave with each other and form a dense and complex structure while lignin limits the further value-added development and application of straw.In this paper,based on the SO₃ micro-thermal explosion technology of straw,the optimum biocatalyst for lignin degradation of straw was screened.Results showed the hydrogen peroxide catalyzed by extracellular enzyme solution of Serratia mucosae could effectively degrade some of the straw,enlarging the internal space of straw and benefit to the subsequent alkali washing to strip lignin and obtain a higher content of holocellulose.The holocellulose was used as a material and a new tablet disintegrant,rice straw holocellulose was obtained,which qualified the indexes of 2015 edition of Chinese Pharmacopoeia for powdered cellulose.Aspirin was used as a model drug to explore the disintegration performance of straw powdered holocellulose as disintegrant.Main conclusions of this paper can be extracted as follows.An optimal technology for straw lignin degradation was obtained by screening the biocatalysts.The lignin content decreased from 12.28%to 4.02%when straw was pretreated with dilute alkali and H₂O₂ oxidation catalyzed by extracellular enzyme solution of Serratia mucilis.On the basis of the above,the lignin residue was 1.7%after optimizing the process.The optimized conditions were as follows:the size of straw was 0.5¹ cm,the amount of enzyme infiltration was 1:15 for 60 min under 55?,the amount of hydrogen peroxide oxidation was 1:15 for 45 min under 55?,the alkali treatment temperature is 60?for 3.5 h.A new disintegrant was obtained by decolorizing and bleaching the obtained holocellulose using sodium chlorite and H₂O₂ oxidation.The process retains a part of hemicellulose of straw and can absorb water rapidly when it is used as disintegrant.The properties qualified the requirements of the 2015 edition of Chinese Pharmacopoeia2015 for powdered cellulose.Straw holocellulose was used as disintegrant for tablet preparing and the properties was tested.An optimum process was obtained through optimization,using the wet granulation to make tablets and add the disintegrant with internal addition method.The same disintegrant result with 15²0%microcrystalline cellulose can be achieved using3⁵%rice straw holocellulose,showing the holocellulose has great potential as high-efficiency disintegrants.