Purification and identification of xanthine oxidase inhibitory peptides from enzymatic hydrolysate of α-lactalbumin and bovine colostrum casein.

The development of food-derived Xanthine Oxidase (XO) inhibitors is critical to the treatment of hyperuricemia and oxidative stress-related disease. Few studies report on milk protein hydrolysates' XO inhibitory activity, with the mechanism of their interaction remaining elusive. Here, different commercial enzymes were used to hydrolyze α-lactalbumin and bovine colostrum casein. The two proteins hydrolyzed by alkaline protease exhibited the most potent XO inhibitory activity (bovine casein: IC50 = 0.13 mg mL-1; α-lactalbumin: IC50 = 0.28 mg mL-1). Eight potential XO inhibitory peptides including VYPFPGPI, GPVRGPFPIIV, VYPFPGPIPN, VYPFPGPIHN, QLKRFSFRSFIWR, LVYPFPGPIHN, AVFPSIVGR, and GFININSLR (IC50 of 4.67-8.02 mM) were purified and identified from alkaline protease hydrolysates by using gel filtration, LC-MS/MS and PeptideRanker. The most important role of inhibiting activity of peptides is linked to hydrophobic interactions and hydrogen bonding based on the results of molecular docking and molecular dynamics simulation. The enzymatic hydrolysate of α-lactalbumin and bovine colostrum casein could be a competitive candidates for hyperuricemia-resisting functional food.

[Transcriptome analysis reveals genes involved in biosynthesis of secondary metabolism in Cornus officinalis].

In order to explore genetic basis for the biosynthesis of secondary metabolism,the transcriptome of Cornus officinalis was sequenced by the new generation of high-throughput sequencing technology,A total of 96 032 unigenes were assembled with an average length of 590.53 bp. Among them, 35 478 unigenes were annotated in the public databases NR,Swissprot,COG,GO,KOG,Pfam and KEGG. Based on the assignment of KEGG pathway, 84 involved in ridoid biosynthesis and 487 unigenes involved in others secondary metabolites biosynthesis were found. Additionally,53 unigenes and 72 unigenes were predicted to have potential functions of cytochome P450 and UDP- glycosyltransferases based on the annotation result, which may encode responsible for secondary metabolites modification. This study was the first comprehensive transcriptome analysis for C. officinalis, and the candidate genes involved in the biosynthesis of secondary metabolites were obtained. The transcriptome data constitutes a much more abundant genetic resource that can be utilized to benefit further molecular biology studies on C. officinalis.

A new sesquiterpene lactone from the fruits of Illicium henryi.

AIM: To study the chemical constituents of the fruits of Illicium henryi. METHOD: Chromatographic separations on silica gel, Sephadex LH-20 gel and MCI gel were used to isolate the compounds. The structures were elucidated based on extensive spectroscopic data analyses. RESULTS: Seven compounds were obtained and their structures were identified as 10-benzoyl-cycloparvifloralone (1), cycloparvifloralone (2), 2α-hydroxycycloparviforalone (3), henrylactone B (4), merrillianone (5), henrylactone C (6) and 7, 14-ortholactone- 3-hydroxyfloridanolide (7). CONCLUSION: Compound 1 is a new sesquiterpene lactone. The tested compounds showed weak anti-HBV activities on HBV surface antigen (HBsAg) secretion and HBV e antigen (HBeAg) secretion using Hep G2.2.15 cell line.

Two new monoterpenes from the fruits of Illicium lanceolatum.

Two new monoterpenes, p-mentha-1(7),8-dien-2-O-ß-D-glucoside and trans-2,4-dihydroxy-2,4-dimethyl-trans-1-acetic acid γ-lactone were isolated from the fruits of Illicium lanceolatum along with trans-2,4-dihydroxy-2,4-dimethyl-cis-1-acetic acid γ-lactone, (1R,2R,4R)-8-p-menthen-1,2-diol, trans-sobrerol, (1S,2S,4R)-p-menthane-1,2,8-triol and (1S, 2S, 4R, 8R)-p-menthane-1,2,9-triol. The structures of the isolates were confirmed by spectroscopic analysis and they showed no inhibitory effects on the in vitro growth of microbial organisms (Escherichia coli, Staphyloccocus aureus, Bacillus subtilis) at less than 1.0 mg/mL.