Isolation and analysis of four constituents from barks and leaves of Eucommia ulmoides Oliver by a multi-step process

Barks and leaves of Eucommia ulmoides Oliver (EU) were successively fractionated by a multi-step treatment process. The extractum and water-soluble polysaccharides, alkali-extractable polysaccharides, and guttapercha, were sequentially obtained by hot-water extraction, alkaline treatment, and extended enzymatic hydrolysis, respectively. Results showed that the primary bioactive components of extractum from leaves were mainly consisted of chlorogenic acid, quercetin, geniposide and aucubin, and those from barks were consisted of geniposidic acid, geniposide and aucubin. In addition, the water-soluble polysaccharides from barks and leaves were mainly composed with glucose, whereas, the alkali-extractable polysaccharides from the barks and leaves were primarily the arabinose. Emphatically, the guttapercha fractions obtained from barks exhibited higher molecular weights with narrow polydispersity as compared to those from leaves. The data presented indicated that the multi-step process is an environmentally benign and advantageous scheme for value-added and potential industrial application of EU resources.