化学法和生物法制备巨菌草腐植酸的比较

对化学方法和生物方法制备巨菌草(Pennisetum sp.)腐植酸和黄腐酸进行分析比较。结果表明,硝酸、盐酸、乙酸、草酸、氨水均能降解纤维素、半纤维素或木质素从而生产腐植酸和黄腐酸,其中10.0%氨水提取巨菌草得到的腐植酸含量最高,其次为37.5%硝酸和37.5%盐酸,草酸和乙酸提取得到的腐植酸含量最低。枯草芽孢杆菌(Bacillus subtilis)、毛霉(Mucor)、根霉(Rhizopus)、青霉(Penicillium)在巨菌草腐殖质的形成中均起到了积极作用,其中根霉对木质素的降解程度最高,生成总腐植酸的含量最高。根霉发酵制备得到的总腐植酸含量是10.0%氨水提取得到的总腐植酸含量的1.45倍,毛霉发酵制备得到的总腐植酸含量是10.0%氨水提取得到的总腐植酸含量的1.29倍,而枯草芽孢杆菌和青霉发酵制备得到的总腐植酸含量比10%氨水提取得到的总腐植酸含量低。37.5%硝酸提取得到的黄腐酸含量是毛霉发酵制备得到的黄腐酸含量的1.79倍,22.5%盐酸提取得到的黄腐酸含量是毛霉发酵制备得到的黄腐酸含量的1.98倍。综上可知,生物发酵法制备得到的总腐植酸含量比化学法提取得到的总腐植酸含量要高,而化学方法提取得到的黄腐酸含量比生物发酵法制备得到的黄腐酸含量要高。

Comparison of chemical and biological methods to measure humic acid content in Pennisetum sp.

The humic and fulvic acids in Pennisetum sp.were compared with chemical and biological methods. Cellulose,hemicellulose,and lignin were degraded to produce humic acid and fulvic acid with nitric acid,hy-drochloric acid,acetic acid,oxalic acid,and ammonia.The humic acid content was the highest when using 10.0% ammonia,followed by 37.5% nitric acid and 37.5% hydrochloric acid,while oxalic acid and acetic acid were the lowest.Bacillus subtilis,Mucor,Rhizopus,and Penicillium played a positive role in the formation of humic and fulvic acids.The degradation degree of lignin was the highest when using Rhizopus.The total hu-mic acid contents were 1.45 and 1.29 times that of 10.0% ammonia under Rhizopus and Mucor fermentation, respectively,while the total humic acid contents were less than 10.0% ammonia under both B.subtilis and Penicillium fermentation.The content of fulvic acid using 3 7.5% nitric acid was 1.7 9 times that of Mucor fer-mentation,and the content of fulvic acid using 22.5% hydrochloric acid was 1.98 times that of Mucor fermenta-tion.