Beneficial effects of Houttuynia cordata polysaccharides on “two-hit” acute lung injury and endotoxic fever in rats associated with anti-complementary activities

Lu, Yan; Jiang, Yun; Ling, Lijun; Zhang, Yunyi; Li, Hong; Chen, Daofeng

CHCP was prepared through the process of water extraction, alcohol precipitation and deproteinization as previously reported 20 . The dried whole plant of H. cordata was grounded and defatted with 95% ethanol. The residue was extracted with hot water. The water extract was concentrated and precipitated with trichloroacetic acid to remove proteins. The supernatant was dialyzed in running water for 3 days, and then precipitated by adding 4 volumes of 95% ethanol. The precipitate was lyophilized to yield the polysaccharides (CHCP). The total carbohydrate content was determined with the phenol-sulfuric acid using D-galactose as the standard. The m-hydroxybiphenyl method was used to test the uronic acid content with D-galacturonic acid as the standard. The concentration of total protein was evaluated using the Coomassie brilliant blue method, with bovine serum albumin as the standard. High performance gel permeation chromatography (HPGPC) was carried out to analyse the molecular weight of CHCP on a TSKgel GMPWxl column (300 mm × 7.6 mm, TOSOH, Japan). Gas chromatography (GC) was used to analyze the monosaccharide composition of the completely hydrolyzed CHCP on a HP6890 (Hewlett-Packard, Wilmington, USA) fitted with a capillary column DB-225 ( Buffers: barbitol buffer solution (BBS), containing 0.5 mmol/L Mg 2þ and 0.15 mmol/L Ca 2þ . GVB-Mg-EGTA, veronal buffer saline, containing 5 mmol/L Mg 2þ and 8 mmol/L Ca 2þ .