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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 200 mg/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. [ABSTRACT FROM AUTHOR]

Objective To investigate the effects of students' autonomous learning based on the network resource. Methods Fifty-five students in 2013 nursing class of Kunming Medical University were selected as the experimental class, and they were asked to learn independently by using the network resources. Other 54 students in 2013 nursing class were selected as the control class, and given the traditional autonomous learning method. Teachers designed the survey questionnaire and compared the results. Results There was significant difference in the test score between the experimental class and control class (P < 0.05) . The results of questionnaire survey showed that 82.7% students thought autonomous learning was important to the cultivation of comprehensive ability, and 75.9% students thought their abilities of autonomous learning were improved in the experimental class. However, there were 33.2% and 12.1% in the control class, respectively. Conclusion Autonomous learning based on the network resource is important to inspire students' learning interest, improve their self-study and comprehensive abilities. So, the learning mode is worth promoting and applying in undergraduate teaching. [ABSTRACT FROM AUTHOR]

Growth inhibition of Streptococcus mutans (SM), Streptococcus salivarius (SS1), and Streptococcus sanguinis (SS2) were determined at different Sparassis latifolia polysaccharides (SLPs) concentrations (2%, 4%, 8%, 16%) mixed with artificial saliva (AS). Metabolomics was determined by the action of 4% SLPs and AS on each bacterium to obtain the bacteriostatic activity of SLPs on oral processing. The results showed that the 16% mixture could inhibit the growth of the oral bacteria S. mutans, S. salivarius, and S. sanguinis. The inhibitory effect on oral bacteria decreased with decreasing polysaccharide concentration. The metabolic pathways and metabolites analyses screened for active inhibitory substances against oral bacteria. These results implied that SLPs are potential new material for developing oral functional products. [ABSTRACT FROM AUTHOR]

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 × 104 Da. The backbone of HEFP-2b consisted of →6)-linked-α-D-Glc p -(1→ and →4)-β-D-Gal p -(1→ and →3,6) -α-D-Man p linkage, with two side-branching units of (1→ and →6)-β-D-Gal p and (1→ and →4)-α-D-Man p , 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. • Hericium erinaceus , as a medicinal fungus with well-known health-promoting effects • A novel polysaccharide with 22.82% of Gal, HEFP-2b, was obtained from H. erinaceus. • HEFP-2b was able to effectively inhibit the growth of HCT-116 and DLD1 cells. • HEFP-2b could induce arrest of cell cycle at S -phage in the colon cancer cells. [ABSTRACT FROM AUTHOR]

The purpose of this research was to optimize ozone treatment concentration and investigate the one‐time ozone treatment (OOT) and intermittent ozone treatment (IOT) on the physicochemical characteristics and enzyme activity of Shiitake mushroom (Lentinus edodes). The results indicated that the optimal ozone‐treated concentration was 3.21 mg/m3. IOT effectively delayed mushroom browning through the inhibition of polyphenol oxidase (PPO) activity, and promotion of phenylalanine ammonia‐lyase (PAL), peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT) activities. It also maintained high levels of total phenolic and soluble protein content, and reduced the accumulation of free amino acids in mushrooms. The treatment reduced the total number of colonies, molds, and yeasts. Statistical analysis indicated that L* was remarkably positively correlated with POD, CAT, PAL, SOD activity, total phenolic content, and was negatively correlated with the total number of colonies, yeast, and mold. It was concluded that IOT was effective in maintaining mushroom quality and prolong storage life. Practical applications: Lentinus edodes are one of the most popular edible fungi due to its high nutrition value; however, they are prone to quality deterioration during storage. This study presents the application of one‐time ozone treatment (OOT) and intermittent ozone treatment (IOT) to improve the physicochemical characteristics and antioxidant enzyme activities of mushrooms. The finding revealed that IOT could effectively improve the quality of mushrooms by maintaining high level of nutrients, improving the antioxidant enzyme activities, and inhibiting the growth of the microorganisms. This work may provide a potential preservative for maintaining quality and extending the shelf‐life in the processing and preservation of shiitake mushrooms. [ABSTRACT FROM AUTHOR]

Different pretreatments can affect the quality of Hypsizygus marmoreus (HM). In this study, the effects of thermal treatment or combined with color protection and hardening on color, texture, microstructure, polyphenol oxidase (PPO) and Peroxidase (POD) C-1: Explain the first time? activities, and the volatile components of HM were investigated. The results showed compared with the control group, both heating group (H group) and color protection, hardening and heating (CHH group) significantly enhanced the color difference, and reduced all texture parameters as well as PPO and POD activities. Additionally, in two treatment groups, the structure of HM became loose, the amounts of alcohols, ketones, and aldehydes were changed significantly. Compared with the H group, the color difference and PPO activities in CHH group were significantly decreased, while all texture parameters were increased significantly, the fibers of HM showed regular arrangement. In conclusion, the combination of CHH performed better effects on hardness, chewiness, microstructure, and enzymes activities related to enzymatic browning. [ABSTRACT FROM AUTHOR]

Abstract 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 Zn2+, Fe3+, 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. [ABSTRACT FROM AUTHOR]

The physicochemical and digestive properties of Pleurotus eryngiiprotein and the effects of heat treatment and ultrasound treatment on the properties were investigated. The physicochemical property results showed that the shear stress and viscosity increased as the protein concentration increased from 3 to 9 g/100 g raw materials and decreased as the temperature increased from 25°C to 45°C. The pH value from 2.0 to 7.0 significantly affected the state of protein because of the change of the disulfide bond and sulfhydryl bond content. The protein might be held closer with higher sulfhydryl bond at pH 7.0 and be less coacervation with higher disulfide bonds at pH 3.5. The addition of calcium from 0.01 to 0.05 mol/L into the protein system could increase the rheology property of the protein. Based on the results of Fourier-transform infrared spectroscopy, the content of α-helix increased after heat treatment and ultrasound treatment, while the content of β-sheet decreased, indicating the change of spatial conformation of protein. The result of differential scanning calorimetry of protein manifested that ultrasound treatment significantly enhanced the protein thermal stability (P < 0.05). The digestive property results indicated that heat treatment and ultrasound treatment increased the available amino groups (DH) and vitro digestibility of protein digestive juice and reduced the content of peptides. There were more kinds of amino acids of protein digestion with ultrasound treatment than non-treatment and heat treatment. In addition, the protein after ultrasound treatment exhibited excellent antioxidant properties in in vitro digestion. [ABSTRACT FROM AUTHOR]

Rheological properties and gel characteristics of Sparassis crispa polysaccharides (SCPs) were investigated under various concentrations, temperature, pH, salt concentrations, and sucrose concentrations. SCP solutions behaved as shear thinning pseudoplastic fluids; apparent viscosity increased with concentrations but decreased with extreme conditions and was highest for 1% SCPs at 80 ℃ under neutral conditions; 5% SCPs solutions formed a hysteresis loop and exhibited thixotropic properties. By oscillatory measurements, SCPs were viscoelastic materials. 0.5% and 1% SCPs solutions exhibited viscous behavior at low frequency and enhanced elastic property with the oscillation frequency increased. With the concentration increased to 3% and 5%, the elastic property was predominant in solutions and exhibited gel-like behavior. SCPs gel textural properties and water holding capacity increased with concentration (to 20%) and decreased with salinity, extreme sucrose, and pH. 10% SCPs gels were optimized at 10% sucrose in neutral conditions. Thus, these results implied SCPs had the potential utilization as a new hydrocolloid source in food industries. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Flammulina velutipes is a potentially excellent fungus to study basic mechanisms of basidiomycete mycelium biology. To provide a better understanding of the mechanism of hyphae growth and fruit-body formation, the biological functions of the differentially abundant proteins between the fruiting dikaryon and the non-fruiting monokaryon of F. velutipes were investigated at the proteomic level using iTRAQ-coupled two-dimensional liquid chromatography tandem mass spectrometry technique. Among the 1198 proteins identified with high confidence, a total of 472 proteins were detected differentially abundant at least one of the mycelium development stages. In-depth data analysis revealed that differentially expressed proteins were influenced a variety of cellular processes, particularly metabolic processes. Functional pathway analysis indicated that 63 up-regulated proteins at only the fruiting dikaryon (Fv13) stage were mainly distributed in 51 specific Kyoto Encyclopedia of Genes and Genome pathways, such as amino acids biosynthesis and metabolism, signaling pathway, and central carbon metabolism. These up-regulated proteins could possibly serve as potential biomarkers to study the mycelium development pathways as well as provide new insights on the mycelium heterogenic compatibility and fruit-body formation mechanisms of basidiomycetes. [ABSTRACT FROM AUTHOR]