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Background Mushroom polysaccharides have traditionally been used for the prevention and treatment of a multitude of disorders like infectious illnesses, cancers and various autoimmune diseases. Crude mushroom extracts have been tested without detailed chemical analyses of its polysaccharide content. For the present study we decided to chemically determine the carbohydrate composition of semi-purified extracts from 2 closely related and well known basidiomycete species, i.e. Agaricus bisporus and A. brasiliensis and to study their effects on the innate immune system, in particular on the in vitro induction of pro-inflammatory cytokines, using THP-1 cells. Methods Mushroom polysaccharide extracts were prepared by hot water extraction and precipitation with ethanol. Their composition was analyzed by GC-MS and NMR spectroscopy. PMA activated THP-1 cells were treated with the extracts under different conditions and the production of pro-inflammatory cytokines was evaluated by qPCR. Results Semi-purified polysaccharide extracts of A. bisporus and A. brasiliensis (= blazei) were found to contain (1¿6),(1¿4)-linked a-glucan, (1¿6)-linked ß-glucan, and mannogalactan. Their proportions were determined by integration of 1H-NMR signs, and were considerably different for the two species. A. brasiliensis showed a higher content of ß-glucan, while A. bisporus presented mannogalactan as its main polysaccharide. The extracts induced a comparable increase of transcription of the pro-inflammatory cytokine genes IL-1ß and TNF-a as well as of COX-2 in PMA differentiated THP-1 cells. Pro-inflammatory effects of bacterial LPS in this assay could be reduced significantly by the simultaneous addition of A. brasiliensis extract. Conclusions The polysaccharide preparations from the closely related species A. bisporus and A. brasiliensis show major differences in composition: A. bisporus shows high mannogalactan content whereas A. brasiliensis has mostly ß-glucan. Semi-purified polysaccharide

Background Peanut allergy is one of the most common and severe food allergies, and processing is known to influence the allergenicity of peanut proteins. We aimed to establish the effect of heating and glycation on the IgE-binding properties and biological activity of 2S albumins (Ara h 2/6) from peanut. Methodology/Principal Findings Native Ara h 2/6 was purified from raw peanuts and heated in solution (15 min, 110°C) in the presence or absence of glucose. Ara h 2 and 6 were also purified from roasted peanut. Using PBMC and sera from peanut-allergic patients, the cellular proliferative potency and IgE reactivity (reverse EAST inhibition) and functionality (basophil degranulation capacity) of allergens were assessed. Heating Ara h 2/6 at 110°C resulted in extensive denaturation, hydrolysis and aggregation of the protein, whilst Ara h 2 and 6 isolated from roasted peanut retained its native conformation. Allergen stimulation of PBMC induced proliferation and Th2 cytokine secretion which was unaffected by thermal processing. Conversely, IgE reactivity and functionality of Ara h 2/6 was decreased by heating. Whilst heating-glycation further reduced the IgE binding capacity of the proteins, it moderated their loss of histamine releasing capacity. Ara h 2 and 6 purified from roasted peanut demonstrated the same IgE reactivity as unheated, native Ara h 2/6. Conclusions/Significance Although no effect of processing on T-cell reactivity was observed, heat induced denaturation reduced the IgE reactivity and subsequent functionality of Ara h 2/6. Conversely, Ara h 2 and 6 purified from roasted peanut retained the structure and IgE reactivity/functionality of the native protein which may explain the allergenic potency of this protein. Through detailed molecular study and allergenicity assessment approaches, this work then gives new insights into the effect of thermal processing on structure/allergenicity of peanut proteins.

An a-glucan was isolated from the culinary medicinal mushroom A. bisporus by hot water extraction, ethanol precipitation and DEAE-cellulose chromatography. The resulting material showed a single HMW peak excluded from a Sephadex G50 column that could completely be degraded by a-amylase treatment. After heating in 1% SDS a small additional peak of low MW eluted from the G50 column. The monosaccharide composition of the main peak was evaluated by HPLC, and was found to consist of a majority of glucose (97.6%), and a minor proportion of galactose (2.4%). Methylation analysis and degradation by a-amylase indicated the presence of an a-glucan with a main chain consisting of (1®4)-linked units, substituted at O-6 by a-D-glucopyranose single-units in the relation 1:8. Mono- (13C-, 1H-NMR) and bidimensional [1H (obs.),13C-HSQC] spectroscopy analysis confirmed the a-configuration of the Glcp residues by low frequency resonances of C-1 at d 100.6, 100.2, and 98.8 ppm and H-1 high field ones at d 5.06, 5.11, and 4.74 ppm. The DEPT-13C-NMR allowed assigning the non-substituted and O-substituted –CH2 signals at d 60.3/60.8 and 66.2 ppm, respectively. Other assignments were attributed to C-2, C-3, C-4, C-5 and C-6 of the non-reducing ends at d 71.8; 72.8; 70.0; 71.3 and 60.3/60.8 ppm, respectively. The minor proportion of galactose that was demonstrated was probably derived from a complex between the a-glucan and a low molecular weight galactan

The importance of a properly functioning and well-balanced immune system for maintaining health has become strikingly evident over the past decades. Roughly since World War II, there has been an apparent decrease in the prevalence of “traditional” infectious diseases, with a concomitant increase in immune-related disorders, such as allergies. Causally, a relationship with changes in life-style-related factors such as the increasing use of hygienic practices seems likely. Diet and nutrition can affect the functioning of various immune parameters. This concept can be utilised in attempts to prevent or mitigate allergic reactions via the development of targeted food products or ingredients. This review describes recent findings with respect to food products and ingredients that show potential in this respect, with special emphasis on pro- and prebiotics, ß-glucans and fungal immunomodulatory proteins. What all of these approaches have in common is that they appear to strengthen Th1-mediated immunity, thus possibly restoring defective immune maturation due to overly hygienic living conditions: a little bit of dirt does not seem bad!

AIM: To determine the immunomodulatory effect of Shiitake (a mushroom extract), we tested its effect on liver-mediated immune regulation in a model of immune-mediated colitis. METHODS: Four groups of mice were studied. Colitis was induced by intracolonic instillation of TNBS in groups A and B. Groups A and C were treated daily with Shiitake extract, while groups B and D received bovine serum albumin. Mice were evaluated for development of macroscopic and microscopic. The immune effects of Shiitake were determined by FACS analysis of intra-hepatic and intrasplenic lymphocytes and IFN-¿ ELISPOT assay. RESULTS: Administration of Shiitake resulted in by an increased intrasplenic/intrahepatic CD4/CD8 lymphocyte ratio. These effects were accompanied by a 17% increase in the number of intrahepatic natural killer T (NKT) cells. A similar effect was observed when Shiitake was administered to animals without disease induction. CONCLUSION: Shiitake extract affected livermediated immune regulation by altering the NKT lymphocyte distribution and increasing intrahepatic CD8+ T lymphocyte trapping, thereby leading to alleviation of immune-mediated colitis marked alleviation of colitis, manifested by significant improvement in the macroscopic and microscopic scores, and by reduction in IFN-¿-producing colonies in group A, compared to group B mice (1.5 pfu/mL vs 3.7 pfu/mL, respectively). This beneficial effect was associated with a significant increase in the intrahepatic CD8+ lymphocyte trapping, demonstrated

We discuss current information on the ability of extracts and isolated metabolites from mushrooms to modulate immune responses. This can result in a more enhanced innate and acquired disease resistance. The major immunomodulating effects of these active substances derived from mushrooms include mitogenicity and activation of immune effector cells, such as lymphocytes, macrophages, and natural killer cells, resulting in the production of cytokines, including interleukins (ILs), tumor necrosis factor alpha (TNF)-¿, and interferon gamma (INF)-¿. In particular, the ability of selective mushroom extracts to modulate the differentiation capacity of CD4+ T cells to mature into TH1 and/or TH2 subsets will be discussed. As a consequence these extracts will have profound effects in particular diseases, like chronic autoimmune TH1-mediated or allergic TH2-mediated diseases. Immunosuppressive effects by mushroom components have also been observed. The therapeutic effects of mushrooms, such as anticancer activity, suppression of autoimmune diseases, and allergy have been associated with their immunomodulating effects. However, further studies are needed to determine the molecular mechanisms of the immunomodulating effects of mushrooms metabolites both individually and in complex mixtures, for example, extracts

In vitro cultured plant cells can be utilized for the production of valuable metabolites. Many biochemical and physiological characteristics of ln vitro cultured plant cells depend on various environmental parameters, such as the composition of the growth medium in which many parameters are represented. [...] In this thesis the production of L-DOPA wlth in vitro grown cells of Mucuna pruriens L. was stud'ied. ... Zie: Summary