title: Characterization of two water-soluble lignin metabolites with antiproliferative activities from Inonotus obliquus.
abstract: The chaga mushroom, Inonotus obliquus has long been recognized as a remedy for cancer, gastritis, ulcers, and tuberculosis of the bones since the 16th century. Herein we reported the identification of two homogenous biological macromolecules, designated as IOW-S-1 and IOW-S-2 with anti-tumor activities from the hot-water extract of I. obliquus. Their molecular weights were determined to be 37.9 and 24.5kDa by high performance gel permeation chromatography (HPGPC) respectively. Chemical and spectral analysis indicated that both IOW-S-1 and IOW-S-2 were predominant in lignin, along with ∼20% carbohydrates. Examination of cytotoxicity showed that these two lignin-carbohydrate complexes induced cell death in a concentration dependent manner, while this apoptosis induction was largely cell-cycle independent. Further investigation demonstrated that IOW-S-1 or IOW-S-2 inhibited the activation of the nuclear transcription factor in cancer cells. These findings implied that soluble lignin derivatives were one of bioactive components in I. obliquus, and further provided insights into the understanding of molecular basis for diverse medicinal and nutritional values of this mushroom.
authors.affiliation: College of Science, Northwest A&F University, Yangling 712100, Shaanxi, China.
authors.forename: Qingjie
authors.initials: Q
authors.lastname: Wang
authors.affiliation: College of Science, Northwest A&F University, Yangling 712100, Shaanxi, China.
authors.forename: Haibo
authors.initials: H
authors.lastname: Mu
authors.affiliation: College of Science, Northwest A&F University, Yangling 712100, Shaanxi, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Zhang
authors.affiliation: College of Science, Northwest A&F University, Yangling 712100, Shaanxi, China.
authors.forename: Dongqi
authors.initials: D
authors.lastname: Dong
authors.affiliation: College of Science, Northwest A&F University, Yangling 712100, Shaanxi, China.
authors.forename: Wuxia
authors.initials: W
authors.lastname: Zhang
authors.affiliation: College of Science, Northwest A&F University, Yangling 712100, Shaanxi, China. Electronic address: jduan@nwsuaf.edu.cn.
authors.forename: Jinyou
authors.initials: J
authors.lastname: Duan
mesh_terms: D001487:Basidiomycota / Q000737:chemistry*; D002453:Cell Cycle / Q000187:drug effects; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D006801:Humans; D008031:Lignin / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D016328:NF-kappa B / Q000037:antagonists & inhibitors; D019906:Nuclear Magnetic Resonance, Biomolecular; D012995:Solubility; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D016328:NF-kappa B; D008031:Lignin
keywords: Biopolymers; Carbohydrate; Fungus; Lignin; NF-κB inhibition