Exploring the Antioxidant Potential of Methanolic Extracts of Wild Medicinal and Edible Mushrooms from Darma Valley, Pithoragaph, Kumaun (Himalaya, India).

This study presents a comprehensive analysis of the methanolic extracts of nine species of wild edible mushrooms (WEM) native to the Darma Valley in the Kumaun Himalaya region. The investigation encompasses the assessment of various biochemical attributes, including total phenolics (TP), total flavonoids (TF), total tannins (TT) contents, the ABTS assay, and the DPPH radical scavenging assay. Among the nine WEM species examined, Clavatia craniiformis stands out for displaying the highest antioxidant capacities, indicated by exceptional TP (54.94 ± 0.54 mg gallic acid equivalenta/g dry weight) and TT (4.23 ± 0.17 mg tannic acid equivalents/g dry weight) contents, along with noteworthy ABTS (10.44 ± 0.34 mg abscorbic acid equivalents/g dw) and DPPH activity (0.335 ± 0.001 mg abscorbic acid equivalents/g dry weight). Subsequent antioxidant potential are mushrooms Ramaria fennica, Ramaria botrytis, Ramaria sanguinea, Ramaria flava, Gomphus. clavatus, Clavaria zollingeri, Pleurotus ostreatus, and Kuehneromyces mutabilis. Variations in antioxidant capacities align with distinct phenolic content. This study underscores as a remarkable source of antioxidants, suggesting its potential suitability for nutraceutical applications. The findings contribute to a deeper understanding of the antioxidant properties inherent in wild edible mushrooms, particularly emphasizing the prominence of C. craniiformis.

Effect of selenium and zinc biofortification on the biochemical parameters of Pleurotus spp. under submerged and solid-state fermentation.

BACKGROUND: Pleurotus has a remarkable nutritional and nutraceutical profile due to mineral mobilization and accumulation abilities from the substrate. The present study aimed to observe the effect of single and dual supplementations Se and Zn on biochemical parameters of P. florida, P. sajor caju and P. djamor. Also, the bioaccumulation of the trace elements in fortified mushrooms was estimated. METHODS: Biomass production and radial growth rate were observed on Se and Zn supplemented broth and agar based medium. Furthermore, the influence of Se and Zn supplementation was recorded on the fruit body yield. The colorimetric assays were employed to estimate total soluble protein, total phenol and total flavonoid contents. The antioxidant activity was assayed as DPPH radical scavenging test. While, ICP-AES was performed to estimate the variation in the Zn and Se content of the fruit bodies. RESULTS: The Se supplementation at low rate resulted in improvement in the radial growth rate and biomass production for P. sajor caju. For solid-state fermentation, a better yield was obtained with inorganic salt supplementation in comparison to organically enriched Se straw. The maximum total soluble protein content and total flavonoid content were observed in fruit bodies of P. sajor caju at 4 mg L -1 of Se and Se-Zn respectively. Pleurotus djamor exhibited the highest total phenolic content on Zn supplementation (10 mg L-1). Improved antioxidant potential was recorded with dual supplementations. Salt supplementations caused shrinkage, distortion of the fungal hyphae, and decreased basidiospores with significant amelioration in elemental composition in fortified mushrooms. CONCLUSION: The inorganic salt supplementation increased the biochemical potential of Pleurotus spp. in comparison to organically enriched substrate which could further be used for the development of dietary supplements.

Enrichment of Culinary-Medicinal Oyster Mushroom, Pleurotus ostreatus (Agaricomycetes), Cultivated on the Straw Substrate with Zinc and Selenium.

Pleurotus ostreatus was cultivated on a commercially available wheat straw substrate enriched with Zn and Se. Various amounts of Zn (10, 50, and 100 mg) and Se (1, 5, and 10 mg) in suitable forms ((CH3COO)2Zn·2H2O, Zn(NO3)2·6H2O, and Na2SeO3·5H2O, respectively) were dissolved in 50 ml of deionized water and homogenously nebulized into the substrate block of 2.4 kg weight. The increase in the Zn content in fruiting bodies cultivated on the enriched substrate was relatively low compared with fruiting bodies cultivated on the substrate with no addition at the first flush. The application of different Zn compounds (acetate vs. nitrate) gave similar results. However, the addition of 1 mg of Se into the cultivation substrate block increased the content of Se in fruiting bodies to about 3-6 mg/kg dry matter. This content was one order of magnitude higher compared with the Se content in fruiting bodies harvested from the substrate with no Se addition (< 0.12-0.58 mg/kg dry matter). In the case of the addition of 5 mg of Se, there was a further significant increase in the content of this element to about 40-60 mg/kg dry matter.

Activity of Oyster Mushrooms, Genus Pleurotus (Agaricomycetes), on Lucilia cuprina (Diptera).

Lucilia cuprina is a vector of important diseases in humans and animals that causes myiasis in sheep, leading to enormous damage to the sheep sector. Chemical products are used to control these flies; however, there are reports of resistance in addition to these products causing toxicity to the environment, humans, and animals, so alternative controls have been studied to reduce these impacts. Pleurotus spp. are basidiomycete fungi and present bioactive compounds with medicinal properties. Due to the potential use of fungi to control Diptera, this study aimed to verify the activity of Pleurotus florida, P. ostreatus, and P. djamor in the control of larvae and adults of L. cuprina, as well as the effects of aqueous extracts of the fungi P. ostreatus, P. djamor, and P. florida on larvae and adults of L. cuprina. The aqueous extract from P. florida was the only one that showed larvicidal activity against L. cuprina, with a half-maximal effective concentration of 11.42 mg/mL. In the test with adult stages, 30 insects were used for each solution concentration, sprinkled with 1 mL of the solution. All aqueous extracts showed adulticidal activity at all concentrations, P. ostreatus showing the best results, with adult mortality ranging from 75.86 to 100%. Our results demonstrated an important larvicidal effect of P. florida and an adulticidal effect of all AE, with emphasis on P. ostreatus.

Metabolite Profiling of Pleurotus ostreatus Grown on Sisal Agro-Industrial Waste Supplemented with Cocoa Almond Tegument and Wheat Bran.

Pleurotus ostreatus is an edible fungus with high nutritional value that uses industrial and agricultural lignocellulosic residues as substrates for growth and reproduction. Understanding their growth metabolic dynamics on agro-industrial wastes would help to develop economically viable and eco-friendly biotechnological strategies for food production. Thus, we used UHPLC/MS/MS and GNPS as an innovative approach to investigate the chemical composition of two strains of P. ostreatus, coded as BH (Black Hirataki) and WH (White Hirataki), grown on sisal waste mixture (SW) supplemented with 20 % cocoa almond tegument (CAT) or 20 % of wheat bran (WB). Metabolite dereplication allowed the identification of 53 metabolites, which included glycerophospholipids, fatty acids, monoacylglycerols, steroids, carbohydrates, amino acids, and flavonoids. This is the first report of the identification of these compounds in P. ostreatus, except for the steroid ergosterol. Most of the metabolites described in this work possess potential biological activities, which support the nutraceutical properties of P. ostreatus. Thus, the results of this study provide essential leads to the understanding of white-rot fungi chemical plasticity aiming at developing alternative biotechnologies strategies for waste recycling.

Structural Characterization and Immunobiological Activity of Polysaccharides from Astragalus Oyster Mushroom.

When added to mushroom growing substrates, edible and medicinal herbs affect the mushrooms' nutritional and medicinal value. In this study, polysaccharides (P0OP-I and P15OP-I) were extracted and purified from oyster mushrooms grown on substrates supplemented with 0% and 15% Astragalus roots (P0 and P15), respectively, and their chemical structure and immunobiological activities were compared. P15OP-I and P0OP-I were extracted using ultrasound-assisted hot water and deproteinized with the Sevage method, depigmented with 30% H2O2, desalted with dialysis, and purified using DEAE-52 cellulose and Sephadex G-100 dextran column chromatography. The molecular weight of P0OP-I and P15OP-I was 21,706.96 and 20,172.65 Da, respectively. Both were composed of monosaccharides D-mannose, galacturonic acid, D-glucose, D-galactose, and L-arabinose but in different molar ratios, and both were connected by a pyranoside linkage. P15OP-I consisted of higher contents of mannose, glucose, galactose and arabinose and lower content of galacturonic acid as compared to P0OP-I. Both P0OP-I and P15OP-I induced NO and TNF-α production but did not show cytotoxic effect or induce ROS generation in RAW264.7 cells. P15OP-I showed a stronger ability to promote NO and TNF-α production relative to P0OP-I. In vitro experiments showed that the immunomodulatory activity of P0OP-I and P15OP-I in RAW264.7 macrophages were mediated by the JNK/MAPK, Erk/MAPK, and NF-κB signaling pathways. The results would be helpful for elucidation of the health promoting mechanism of Astragalus oyster mushrooms as a source of neutraceuticals.

King Oyster Mushroom, Pleurotus eryngii (Agaricomycetes), Extract Can Attenuate Doxorubicin-Induced Lung Damage by Inhibiting Oxidative Stress in Rats.

Doxorubicin (DOX), a broad spectrum chemotherapeutic, has toxic effects on healthy tissues. Mitochondrial processes and oxidative stress act in the DOX-induced toxicity, therefore antioxidant therapies are widely used. The study was aimed to evaluate the therapeutic potential of Pleurotus eryngii extract (PEE), an extract of a fungus with antioxidant properties, against DOX-induced lung damage. Rats were divided into Control, DOX, DOX + PEE, and PEE groups (n = 6). DOX was administered intraperitoneally in a single dose (10 mg/kg BW) and PE (200 mg/kg BW) was administered by oral gavage every other day for 21 days. Histopathological evaluations, immunohistochemical analyses, total oxidant status (TOS)/total antioxidant status (TAS) method, and quantitative real-time polymerase chain reaction (qRT-PCR) analysis were performed. DOX led to severe histopathological disruptions in rat lungs. Also, DOX remarkably increased the expression of dynamin 1 like (DRP1) and decreased the expression of mitofusin 1 (MFN1) and mitofusin 2 (MFN2) genes, which are related to mitochondrial dynamics. Moreover, DOX caused an increase in TOS/ TAS and 8-hydroxy-2-deoxyguanosine (8-OHdG) levels. On the other hand, PEE treatment remarkably normalized the histopathological findings, mitochondrial dynamics-related gene expressions, markers of oxidative stress, and DNA damage. The present study signs out that PEE can ameliorate the DOX-mediated lung toxicity and the antioxidant mechanism associated with mitochondrial dynamics can have a role in this potent therapeutic effect.

Antimicrobial, Antioxidant, Cytotoxicity and DNA Protective Properties of the Pink Oyster Mushroom, Pleurotus djamor (Agaricomycetes).

In this study, pink oyster mushroom Pleurotus djamor was cultivated using wheat straw (WS), quinoa stalk (QS), and their mixtures (WS-QS (1:1)) as substrate and evaluated in terms of antimicrobial, antioxidant, cytotoxicity, and DNA protective effects. Gram-positive and Gram-negative pathogen bacteria (Bacillus subtilis, Proteus vulgaris, Streptococcus mutans, Salmonella typhi, Pseudomonas aeruginosa, Staphylococcus aureus, and Escherichia coli), dermatophyte (Trichophyton sp.) and yeast (Candida tropicalis) were used in the study. It was found to be very active against all bacteria (except S. mutans and S. typhi), and dermatophyte when compared to the control groups (8.7-33.3 mm), but low against C. tropicalis. It was seen that the best total antioxidant assay (TAS) value was 2.05 mmol/L on WS-QS (1:1). Depend on, it was determined that the total oxidant assay (TOS) value (5.26 µmol/L) in the same compost was lower than the others, and also the scavenging effect of 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) was higher on WS at 25 mg/mL (84.20%). The methanol extract on WS at a concentration of 400 µg/mL, significantly reduced the percentage of viability in the human breast cancer (MDA-MB-231) cell line (2.2%). The methanol extracts on WS and QS medium were found to inhibit DNA damage induced by UV radiation and H2O2 at a concentration of 25 mg/mL. These results showed that pink oyster mushroom has benefits such as antimicrobial, antioxidant, cytotoxic, and DNA protective effects.

Evaluation of the toxicity of crude aqueous Pleurotus tuber-regium (Fr.) Singer extract in mice.

OBJECTIVES: The study aimed to determine the phytochemical profile and safety of the aqueous extract of Pleurotus tuber regium using laboratory animal model. METHODS: The pulverized sample was macerated with water and allowed to stand for 24 h, then filtered. Preliminary qualitative phytochemical screening was carried out on the crude extract and LD50 determination was done using standard procedures. Haematological and serum biochemical parameters to assess the kidney and liver functions were carried out using standard methods. RESULTS: The phytochemical screening revealed the presence of alkaloids, cardiac glycosides, saponins, phenolic compounds, tannins, steroids, carbohydrates, flavonoids and terpenoids. However, anthraquinones were observed to be absent in the extracts. The LD50 of the extract was found to be greater than 5,000 mg/kg when administered orally with no physical signs of toxicity and death over the 14-day period. There was no significant (p>0.05) increase in the level of serum alanine aminotransferase, aspartate transaminase, alkaline phosphatase, blood urea nitrogen and creatinine (p<0.05) when compared to the control group. There was a significant (p<0.05) increase in the total white blood cells of the mice administered with P. tuber-regium. CONCLUSIONS: This study showed that P. tuber-regium (Fr.) Singer does not possess toxic principles, hence, the wide safety margin observed in the mice.

Anticancer Properties of Selenium-Enriched Oyster Culinary-Medicinal Mushroom, Pleurotus ostreatus (Agaricomycetes), in Colon Cancer In Vitro.

Mushrooms have become an important way to safely supply the body with the daily needs of organic selenium and they also possess remarkable medicinal properties. In this study, we examined the ability of the Pleurotus ostreatus mushroom to grow in selenium (Se) and its ability to accumulate and convert Se from inorganic form to organic form during growth. Additionally, we achieved the potential anticancer properties of mushroom extract in colon cancer cells using the CaCo-2 cell and the normal human colon mucosal epithelial cell line, NCM-460 cell line. Interestingly, Se-enriched mushroom extract (SME) showed a competitive regulation in colon cancer cell line; CaCo-2 cell line indicated by cell morphology, the number of survived cells, lactate dehydrogenase (LDH) production, and cell viability rate. Moreover, SME treatment regulates the expression profile of the cancer cell proliferation factor Raf-1 and pro-apoptotic related factors P53 and Caspase-3 Furthermore, the production of inflammatory-regulated cytokines, including interleukin 6 (IL-6) and IL-10, increased. At the same time, the level of produced tumor necrosis factor-alpha (TNF-α) markedly decreased in a dose and time-dependent of colon cancer-treated cells. Notably, the purified selenomethionine (SeMe) showed sufficient inhibition of colon cancer proliferation compared with the inorganic form of selenium (sodium selenite) via blocking the Raf/MEK/ERK signaling pathway. In addition, SeMe treatment also stimulated the production of IL-6 and IL-10 while decreasing the production of TNF-α, which plays a crucial role in the necrotic event. Meanwhile, the SeMe treatment showed a neglected cytotoxic effect in the normal colon epithelial cells. Collectively, these findings indicate that the fruiting bodies of Se-enriched mushrooms revealed anti-colon cancer activity via targeting Raf-1 signaling pathway and increasing the production of IL-6 and IL-10.

Antiprotozoal Activity of Mycelial Extracts of Several Medicinal Agaricomycetes Mushrooms against Giardia duodenalis.

Despite knowledge on the therapeutic properties of fungal bio-compounds, few studies have been reported on their anti-parasitic activities. The anti-parasitic activity (APA) of mycelial extracts from seven medicinal agaricomycetous mushrooms (Polyporus lipsiensis, Ganoderma applanatum, Pleurotus ostreatus, P. flabellatus, Oudemansiella canarii, Lentinula edodes, and Pycnoporus sanguineus) against Giardia duodenalis, and identification of chemical compounds produced by mycelium P. lipsiensis mycelium, have been reported. The extracts of mycelia and fermented culture broths of tested mushroom species were evaluated against G. duodenalis by biological assays. P. lipsiensis showed the highest APA. The chemical analysis of mycelial extract of P. lipsiensis by gas chromatography-mass spectrometry (GC-MS) identified 73 molecules, including steroids, terpenes, and lipids. According to literature data, among these molecules, 11 possess APA. The present study revealed the diversity of compounds with anti-protozoal potential produced by mycelia of Agaricomycetes mushrooms, particularly P. lipsiensis against G. duodenalis.

Medicinal Properties of the Golden Oyster Mushroom, Pleurotus citrinopileatus (Agaricomycetes), Grown on Local Agricultural Wastes in Turkey.

In this study, the antimicrobial, antioxidant, cytotoxicity, and DNA protective effects of Pleurotus citrinopileatus cultured on substrates were investigated. The methanol extract of P. citrinopileatus showed lower activity against Streptococcus mutans (17.0-21.7 mm), Salmonella thypii (12.3-17.7 mm), and Candida tropicalis (16.3-20.3 mm) but was observed to be very active against Trichopyton sp. (14.0-22.3 mm), Bacillus subtilis (17.3-20.3 mm), Pseudomonas aeruginosa (13.0-20.3 mm), Proteus vulgaris (18.3-23.7 mm), Staphylococcus aureus (16.3-23.0 mm), and Escherichia coli (16.0-24.0 mm) compared with the control group. P. citrinopileatus demonstrated significant antioxidant potential. The highest total antioxidant assay (2.76 mmol/L) and total oxidant assay (11.98 µmol/L) values were determined on wheat straw-quinoa stalk (WS-QS; 1:1) and QS medium, and their effectiveness at removing 2,2-diphenyl-1-picrylhydrazyl radicals was more efficient at groups to which samples of 25 mg (74.72-79.80%) were added. The methanol extracts of P. citrinopileatus grown on WS, QS, and WS-QS (1:1) substrates were found to prevent DNA damage induced by ultraviolet radiation and H2O2 at a concentration of 25 mg/mL. The methanol extract of P. citrinopileatus, which was obtained from WS (2.7%) at a 400-µg/mL concentration, remarkably decreased the percentage of viability in the A-549 cell line. These results suggest that P. citrinopileatus has potent antimicrobial, antioxidant, and DNA protective as well as cytotoxic effects on the A-549 cell line.

Characterization of Cytotoxic Proteins from King Tuber Oyster Medicinal Mushroom, Pleurotus tuber-regium (Agaricomycetes), Sclerotium for Human Breast MDA-MB-231 Cancer Cells.

In targeted therapy, proteins/peptides are expected to be more effective as anticancer and/or antitumor agents. Our previous study showed that the protein fraction of Pleurotus tuber-regium (Fr.) Singer sclerotia (PS60) possesses significant cytotoxic activity against the MDA-MB-231 breast cancer cell line, with a 50% inhibitory concentration (IC50) of 0.75 ± 0.57 µg/mL. The current study aimed to further separate and characterize cytotoxic PS60 proteins from P. tuber-regium sclerotia toward MDA-MB-231. The separation of PS60 was conducted using fast protein liquid chromatography. The MTT assay was used to analyze the cytotoxic activity of the protein peaks separated from PS60. Then all of the protein peaks were characterized using liquid chromatography quadrupole time-of-flight mass spectrometry analysis. Three protein peaks (Q1, Q2, and Q3) were successfully separated from PS60. Both the PS60 and protein peaks have shown significant cytotoxic effects against MDA-MB-231 cell growth, with an IC50 < 1.00 µg/mL. Cytotoxic proteins were identified and characterized as kinesin-like protein and keratin type 1, cytoskeletal 10. Several potential cytotoxic proteins from P. tuber-regium sclerotia reactive against MDA-MB-231 breast cancer cells were identified.

Biotreatment of Selected Agrowaste Products with Some Culinary-Medicinal Mushrooms Enhances Their Nutrient Composition for Use as Animal Feed in Nigeria.

Biological treatment of agrowaste products using white-rot fungi can enhance their physicochemical and nutritional values for further use as animal feed. In this study, sweet orange and ripe plantain peels were biotreated during their use as substrates to grow three mushroom species (Lentinus squarrosulus, Pleurotus pulmonarius, and P. ostreatus), with the aim to reuse these wastes for animal feed. The effects of mushroom biotreatment on these wastes were analyzed at 0, 30, and 60 days of incubation with respect to physical and chemical properties of the substrates. Results from the mineral composition revealed the presence of appreciable quantities of sodium, magnesium, phosphorus, nitrogen, calcium, potassium, and iron for both peels after treatment with all of the mushrooms. The amino acid content of orange peels treated with L. squarrosulus and P. pulmonarius increased after treatment compared with the control and plantain peel. The carbohydrate level in both wastes also increased after treatment with L. squarrosulus, P. pulmonarius, and P. ostreatus, respectively, while the moisture and ash contents of treated wastes decreased as the incubation periods progressed. However, there was no significant difference (P ≤ 0.05) in the protein, fiber, and fat content of the control compared to those of treated wastes. This study affirms that biotreatment of these agrowaste products using the selected mushrooms can enhanced their value for further use.

Biofortification of Three Cultivated Mushroom Species with Three Iron Salts-Potential for a New Iron-Rich Superfood.

Mushrooms fortified with iron (Fe) can offer a promising alternative to counter the worldwide deficiency problem. However, the factors that may influence the efficiency of fortification have not yet been fully investigated. The aim of this study was to compare the effects of three Fe forms (FeCl3 6H2O, FeSO4 7H2O, or FeHBED) in three concentrations (5, 10, or 50 mM) for three mushroom species (Pleurotus eryngii, P. ostreatus, or Pholiota nameko) on their chemical composition, phenolic compounds, and organic acid production. The most effective metal accumulation of all the investigated species was for the 50 mM addition. FeCl3 6H2O was the most favorable additive for P. eryngii and P. nameko (up to 145 and 185% Fe more than in the control, respectively) and FeHBED for P. ostreatus (up to 108% Fe more than in control). Additionally, P. nameko showed the highest Fe accumulation among studied species (89.2 ± 7.51 mg kg-1 DW). The creation of phenolic acids was generally inhibited by Fe salt supplementation. However, an increasing effect on phenolic acid concentration was observed for P. ostreatus cultivated at 5 mM FeCl3 6H2O and for P. eryngii cultivated at 5 mM FeCl3 6H2O and 5 mM FeSO4 7H2O. In the case of organic acids, a similar situation was observed. For P. ostreatus, FeSO4 7H2O and FeHBED salts increased the formation of the determined organic acids in fruiting bodies. P. eryngii and P. nameko were characterized by a much lower content of organic acids in the systems supplemented with Fe. Based on the obtained results, we recommend starting fortification by preliminarily indicating which form of the element is preferred for the species of interest for supplementation. It also seems that using an additive concentration of 50 mM or higher is most effective.

The Main Structural Unit Elucidation and Immunomodulatory Activity In Vitro of a Selenium-Enriched Polysaccharide Produced by Pleurotus ostreatus.

In recent years, the structure of selenium-enriched polysaccharides and their application in immunomodulation have attracted much attention. In previous studies, we extracted and purified a novel selenium-enriched Pleurotus ostreatus polysaccharide called Se-POP-21, but its structure and immunomodulatory activity were still unclear. In this study, the main structural unit formula of Se-POP-21 was characterized by methylation analysis and an NMR experiment. The results showed that the backbone of Se-POP-21 was →[2,6)-α-D-Galp-(1→6)-α-D-Galp-(1]4→2,4)-ß-L-Arap-(1→[2,6)-α-D-Galp-(1→6)-α-D-Galp-(1]4→, branched chain of ß-D-Manp-(1→ and ß-D-Manp-(1→4)-ß-L-Arap-(1→ connected with →2,6)-α-D-Galp-(1→ and →2,4)-ß-L-Arap-(1→,respectively, through the O-2 bond. In vitro cell experiments indicated that Se-POP-21 could significantly enhance the proliferation and phagocytosis of RAW264.7 cells, upregulate the expression of costimulatory molecules CD80/CD86, and promote RAW264.7 cells to secrete NO, ROS, TNF-α, IL-1ß, and IL-6 by activating the NF-κB protein. The results of this study indicate that Se-POP-21 can effectively activate RAW264.7 cells. Thus, it has the potential to be used in immunomodulatory drugs or functional foods.

Effects of Se(IV) or Se(VI) enrichment on proteins and protein-bound Se distribution and Se bioaccessibility in oyster mushrooms.

A successful mushroom enrichment process must produce foods that have compounds potentially absorbed by the human body. In this study, Pleurotus ostreatus and Pleurotus djamor mushrooms were grown on organic substrate supplemented with different Se(IV) and Se(VI) concentrations, and evaluated in the following features: Fruiting bodies morphology; Se uptake and accumulation; Distribution of proteins and protein-bound Se; Se species identification on enzymatic extracts; Se bioaccessibility; and Distribution of bioaccessible protein-bound Se. Pleurotus djamor grown on Se(IV)-supplemented substrate showed the greatest potential to uptake and accumulate Se. For Se species screening, selenomethionine was identified in white oyster mushroom, while selenomethionine, selenocystine, and Se-methylselenocysteine in pink oyster mushrooms. In soluble fractions from in vitro gastrointestinal digestion assays, Se showed high bioaccessibility (>94%). Lastly, bioaccessible Se species were found to be mainly associated to LMW (<17 kDa) in Pleurotus ostreatus (74%) and Pleurotus djamor (68%) grown on Se(IV)-supplemented substrates.

The protective role of selenium against uptake and accumulation of cadmium and lead in white oyster (Pleurotus ostreatus) and pink oyster (Pleurotus djamor) mushrooms.

Mushrooms are bioaccumulators and have been used to produce Se-enriched foods. However, these fungi can also bioaccumulate potentially toxic metals, producing food dangerous to human health. It is known that co-exposure to Se plays a protective role against metal accumulation and toxicity in some organisms due to its antioxidant properties. Thus, this study aimed to evaluate the protective effect of Se(IV) and Se(VI) on elemental uptake and accumulation as well as proteins and protein-bound Se, Cd, and Pb distribution in Pleurotus mushrooms. Pink oyster and white oyster mushrooms showed high ability to bioaccumulate Se (19-205 µg g-1), Cd (4.5 to 18.8 µg g-1), and Pb (1.6 to 7.0 µg g-1). Growth substrate supplementation with Se(IV) or Se(VI) decreased the Cd total concentration in mushrooms by 4 to 89%, while Se(VI) increased the Pb total concentration by 9% to 187%, compared to growth in absence of Se. It was found that despite molecular weights distributions of mushrooms grown on Se(IV) and Se(VI)-supplemented substrates being similar, Se(VI) supplementation favoured Se interaction with proteins of medium molecular weight (17-44 kDa), when compared to supplementation with Se(IV). Therefore, we propose the supplementation of growth substrates with Se(VI) to reduce eventual Cd accumulation and produce Se-enriched oyster mushrooms.

A natural selenium polysaccharide from Pleurotus ostreatus: Structural elucidation, anti-gastric cancer and anti-colon cancer activity in vitro.

The development and application of new natural selenium polysaccharides with relatively clear structure and excellent activity have become hot and difficult issues. This study used GC-MS and 2D NMR to characterize the detailed chain structure information of selenium polysaccharide (Se-POP-3) from Selenium-enriched Pleurotus ostreatus, and then explored its anti-gastric cancer and anti-colon cancer effects in vitro. Results showed that the main chain of Se-POP-3 was →[3)-ß-D-Glcp-(1]2 â†’ 6)-ß-D-Glcp-(1 â†’ 3,6)-ß-D-Glcp-(1 â†’ 3)-ß-D-Glcp-(1→, and the branch was α-D-Glcp-(1 â†’ [4)-α-D-Glcp-(1]4→, which was connected to the main chain through the O-3 bond of →3,6)-ß-D-Glcp-(1 â†’ glycosidic bond. In addition, Se-POP-3 could reduce viability, induce apoptosis, inhibit migration and invasion, destroy the Bax/Bcl-2 ratio, and inhibit the epithelial-to-mesenchymal transition of MGC-803 and HCT-116 cells in vitro. Moreover, this study also showed that within the concentration range set in this study, Se-POP-3 had no significant effect on the growth of normal cells (NCM460 cells). This study can provide a theoretical basis for the potential application of Se-POP-3 as an anti-gastrointestinal cancer drug or functional food.

Combined effect of olive pruning residues and spent coffee grounds on Pleurotus ostreatus production, composition, and nutritional value.

No previous study assessed the combined effect of olive pruning residues (OLPR) and spent coffee grounds (SCG) on P. ostreatus production and nutritional value. The aim of this study was to determine the capacity of P. ostreatus to degrade lignocellulosic nature of combined OLPR and SCG as well as their resultant nutrient composition. A complete randomized design was adopted with five treatments: S1:100%wheat straw (WS) (control), S2:33%WS+33%SCG+33%OLPR,S3:66%WS+17%SCG+17%OLPR,S4:17%WS+66%SCG+17%OLPR, and S5:17%WS+17%SCG+66%OLPR, and ten replicates per treatment. Substrate's and mushroom's composition were analyzed on chemical scale, including fatty acids and heavy metals profiles, following international standards. Only S1, S2, and S3 were productive, with comparable biological yield, economical yield, and biological efficiency. Organic matter loss decreased with increasing proportions of OLPR and SCG. Percentage lignin loss was higher in S1 than in S2 and S3 (53.51, 26.25, and 46.15% respectively). Mushrooms of S3 had some enhanced nutritional attributes compared to control: decrease in fat, increase in protein, increase in monounsaturated fatty acids, and lower zinc accumulation. Lead was less accumulated in S2 than S1 mushrooms. Sodium content of mushroom decreased in S2 and S3. The latter substrates yielded mushrooms with lower polyunsaturated fatty acids (PUFA) and higher saturated fatty acids (SFA) contents. All mushrooms had a valuable PUFA/SFA. This study suggests using OLPR and SCG in low proportions as nutritional supplements to the commercial wheat straw.