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The fruiting body of Hericium erinaceus has been used to treat digestive system disorder-related diseases for over 2000 years in China. A novel polysaccharide, HEFP-2b, was obtained from H. erinaceus fruiting bodies. Physical and chemical analysis showed that HEFP-2b consisted of fucose, galactose, glucose, and mannose in molar ratio of 11.81:22.82:44.28:21.09, and that its molecular weight was 3.252 × 10 4  Da. The backbone of HEFP-2b consisted of →6)-linked-α-D-Glcp-(1→ and →4)-β-D-Galp-(1→ and →3,6) -α-D-Manp linkage, with two side-branching units of (1→ and →6)-β-D-Galp and (1→ and →4)-α-D-Manp, terminated by Glc and Fuc. The results of the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and cell cycle arrest experiments revealed that HEFP-2b considerably inhibited the growth of colon cancer cells (HCT-116) in vitro. The growth inhibitory effects of HEFP-2b correlated with their ability to arrest the cell cycle at the S-phase. Our results will provide valuable information for future studies on HEFP-2b as a novel health-promoting functional food ingredient that can be used for treating colon cancer., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020. Published by Elsevier B.V.)

A novel 57-kDa acidic α-galactosidase designated as HEG has been purified from the dry fruiting bodies of Hericium erinaceus. The isolation protocol involved ion-exchange chromatography and gel filtration on a Superdex75 column. The purification fold and specific activity were 1251 and 46 units/mg, respectively. A BLAST search of internal peptide sequences obtained by liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis suggested that the enzyme belonged to the GH27 family. The activity of the enzyme reached its maximum at a pH of 6.0 or at 60 °C. The enzyme was stable within an acidic pH range of 2.2-7.0 and in a narrow temperature range. The enzyme was strongly inhibited by Zn 2+ , Fe 3+ , Ag + ions and SDS. The Lineweaver-Burk plot suggested that the mode of inhibition by galactose and melibiose were of a mixed type. N-bromosuccinimide drastically decreased the activity of the enzyme, whereas diethylpyrocarbonate and carbodiimide strengthened the activity slightly. Moreover, the isolated enzyme displayed remarkable resistance to acid proteases, neutral proteases and pepsin. The enzyme could also hydrolyse oligosaccharides and polysaccharides. In addition, acidic protease promoted the hydrolysis of RFOs by HEG. The K m values of the enzyme towards pNPGal, raffinose and stachyose were 0.36 mM, 40.07 mM and 54.71 mM, respectively. These favourable properties increase the potential of the enzyme in the food industry and animal feed applications., (Copyright © 2018. Published by Elsevier B.V.)

Temperature is one of the pivotal factors influencing mycelium growth and fruit-body formation of Flammulina velutipes. To gain insights into hyphae growth and fruit-body formation events and facilitate the identification of potential stage-specific biomarker candidates, we investigated the proteome response of F. velutipes mycelia to cold stresses using iTRAQ-coupled two-dimensional liquid chromatography tandem mass spectrometry (2D LC-MS/MS) technique. Among 1198 proteins identified with high confidence, a total of 63 displayed altered expression level after cold stress treatments. In-depth data analysis reveals that differentially expressed proteins were involved in a variety of cellular processes, particularly metabolic processes. Among the 31 up-regulated proteins, 24 (77.42%) were associated with 22 specific KEGG pathways. These up-regulated proteins could possibly serve as potential biomarkers to study the molecular mechanisms of F. velutipes mycelia response to cold stresses. These data of the proteins might provide valuable evidences to better understand the molecular mechanisms of mycelium resistance to cold stress and fruit-body formation in fungi., Biological Significance: Low-temperature is one of the pivotal factors in some Flammulina velutipes industrial processes influencing mycelium growth, inducing primordia and controlling fruit-body development. Preliminary study has indicated that effectively regulating cultivation could augment the yield by controlling optimal cold stress level on mycelia. However, we are still far from understanding the molecular and physiological mechanisms of adaptation of these fungi at cold stress. In the present study, the experiments reported above were undertaken to investigate chronological changes of protein expression during F. velutipes mycelia in response to cold stress by using iTRAQ-coupled 2D LC-MS/MS technique. This result would provide new insights to the underlying mycelium growth and fruit-body formation mechanisms of basidiomycetes under cold stress., (Copyright © 2017 Elsevier B.V. All rights reserved.)

To evaluate the immune activation and reactive oxygen species scavenging activity of Cordyceps militaris polysaccharides (CMP) in vivo, 24 male and 24 female Kunming mice were randomly divided into four groups. The mice in the four experimental groups were administered 0 (normal control), 50, 100, or 200mg/kg/d body weight CMP via gavage. After 30 days, the viscera index, leukocyte count, differential leukocyte count, immunoglobulin (IgG) levels, and biochemical parameters were measured. The effect of CMP on the expression of tumor necrosis (TNF)-α, interferon (IFN)-γ, and interleukin (IL)-1β in the spleens of experimental mice was investigated by real-time polymerase chain reaction. The results showed that the administration of CMP improved the immune function in mice, significantly increased the spleen and thymus indices, the spleen lymphocyte activity, the total quantity of white blood cells, and IgG function in mice serum. CMP exhibited significant antioxidative activity in mice, and decreased malondialdehyde levels in vivo. CMP upregulated the expression of TNF-α, IFN-γ, and IL-1β mRNA in high-dose groups compared to that observed for the control mice. We can thus conclude that CMP effectively improved the immune function through protection against oxidative stress. CMP thus shows potential for development as drugs and health supplements., (Copyright © 2016 Elsevier B.V. All rights reserved.)