Proximal Composition, Nutraceutical Properties, and Acute Toxicity Study of Culinary-Medicinal Oyster Mushroom Powder, Pleurotus ostreatus (Agaricomycetes).

A compositional study was performed on fruiting-body powder of the culinary-medicinal oyster mushroom Pleurotus ostreatus for applications as a nutraceutical/functional food. Carbohydrates (55 g/100 g dry weight [dw]) and proteins (27.45 g/100 g dw, with an in vitro digestibility of 75%) appear to be the major components, but fat content was low (4 g/100 g dw). Pleurotus powder has important micronutrients such as minerals (Fe, Cu, Zn, Mn, Mg, and Co) and ascorbic acid, as well as nonnutrients (i.e., phenolics) with antioxidant potential. A powder-derived aqueous extract had a phenolic compound content of 138 mg/100 g that showed 2,2-diphenyl-1-picrylhydrazyl radical scavenging and inhibition of membrane-lipid peroxidation activities of 58.3% and 61.4%, respectively. The presence of ß-1,3-1,6-D-glucans was also demonstrated (1.54 g/100 g). An acute toxicity test proved that Pleurotus powder was safe after oral administration to both male and female mice at a dose of 2000 mg/kg. The combination of rich nutritional composition, bioactivity, and safety in P. ostreatus fruiting-body powder highlights its potential as a nutraceutical agent promoting health and life quality.

Oral administration of an aqueous extract from the oyster mushroom Pleurotus ostreatus enhances the immunonutritional recovery of malnourished mice.

Mushroom nutriceutical components have lately attracted interest for developing immunonutritional support. However, there is relatively little information pertaining to the use of mushroom preparations for modulating the metabolic and immunological disorders associated to malnutrition. This study was aimed to evaluate the effects of oral administration of an aqueous extract (CW-P) from Pleurotus ostreatus on the recovery of biochemical and immunological functions of malnourished mice. 8-week old female BALB/c mice were starved for 3days and then refed with commercial diet supplemented with or without CW-P (100mg/kg) for 8days. Regardless of the diet used during refeeding, animal body weights and serum protein concentrations did not differ between groups. Oral treatment with CW-P normalized haemoglobin levels, liver arginase and gut mucosal weight. CW-P increased total liver proteins and also DNA and protein contents in gut mucosa. Pleurotus extract provided benefits in terms of macrophages activation as well as in haemopoiesis, as judged by the recovery of bone marrow cells and leukocyte counts. Moreover, CW-P stimulated humoral immunity (T-dependent and T non-dependent antibodies responses) compared to non-supplemented mice. CW-P extract from the oyster mushroom can be used to develop specific food or nutritional supplement formulations with potential clinical applications in the immunotherapy.

In vitro anti-proliferative effects on NB4 human leukemia cells and physicochemical screening of Pleurotus sp. (higher Basidiomycetes) mycelia from Cuba.

This study examined the phytochemical profile and the in vitro anti-proliferative effects of a hot water mycelial extract from the edible mushroom Pleurotus sp. on NB4 human leukemia cells. Flow-cytometry analyses were used to measure cell viability, cell cycle, and apoptosis in cells incubated 24 h with the extract at doses of 100 and 200 µg/mL. Pleurotus sp. extract reduced cell viability, particularly at the concentration of 200 µg/mL to 82% compared to control cells, and induced apoptosis demonstrated by an increase in the number of annexin V-FITC+ cells (25% at 200 µg/mL). The NB4 cells were arrested in the G2/M phase thus supporting a cell-cycle dependent anticancer mechanism. Although carbohydrates (76.8%, w/w) appear to be the most important antitumor compound, secondary metabolites-like phenolics would also contribute to the anti-proliferative activity. The results indicate that Pleurotus sp. mycelia obtained by submerged fermentation may be an interesting renewable resource for developing functional foods and new antitumor therapeutic agents.

Oral administration of an enzymatic protein hydrolysate from the green microalga Chlorella vulgaris enhances the nutritional recovery of malnourished mice.

This study examined the effects of oral administration of an enzymatic protein hydrolysate from green microalga Chlorella vulgaris (Cv-PH) on the nutritional recovery of malnourished Balb/c mice after a 3-day fasting period. Mice were refed with commercial diet supplemented or not supplemented with Cv-PH (500 mg/kg) for 8 days. Regardless of the diet used during refeeding, animal body weights and serum protein concentrations did not differ between groups. Mice given Cv-PH had a significant increase in hemoglobin concentrations. Most serum amino acid levels were similar in the control and Cv-PH animals. Starved mice refed with Cv-PH showed normal liver functions, as judged by liver weight, protein concentration, and the enzymatic activities of cholinesterase and arginase. Cv-PH increased DNA, protein content, and gut-mucosal weight. In addition, brush-border oligosaccharidase activities were also higher in the Cv-PH group. These findings suggest that Chlorella protein hydrolysate can be used to develop specific formulations suitable for pharmacologic nutrition.