Phytochemical screening and effects on cell-mediated immune response ofPleurotusfruiting bodies powder

Identification of Secondary Metabolites of Interest in Pleurotus djamor Using Agave tequilana Bagasse

Agro-industrial residues represent more than 60% of organic wastes worldwide, which could be used to generate other by-products or to be incorporated into other production chains. For example, bagasse is a waste from the tequila industry in Mexico that could be implemented for mushroom cultivation. Additionally, the substrate influences the growth, development, and production of secondary metabolites of fungi. This work presents a comparative experiment that studies the metabolite production in Pleurotus djamor mushrooms on agave bagasse and barley straw (traditional substrate). The biological efficiency (BE), yield, phenolics and flavonoids, antioxidant capacity, tannins, and the identification of low molecular weight metabolites were evaluated. Five treatments were proposed according to the following mixtures of agave bagasse: barley straw: T1 (1:0), T2 (3:1), T3 (1:1), T4 (1:3), and T5 (0:1). T2 had the highest yield (13.39 ± 3.23%), BE (56.7 ± 13.71%), and flavonoids (44.25 mg rutin equivalent (RE)/g); T3 obtained the highest phenol content (230.27 mg GAE/g); and T1 the highest tannins content (0.23 mg (+) catechin equivalent (CE)/g). Finally, T1 and T5 are the ones that present the greatest number of primary metabolites, including hydroxycitric acid, 2-deoxy-D-galactose, D-mannose, paromomycin, palmitic acid, pyrrole, mannitol, and DL arabinose, while in T2, T3, and T4 only two chemical compounds were found present (palmitic acid and pyrrole in T2, silicic acid and pyrrole in T3 and 2-deoxy-D-galactose and quinoline in T4). The cultivation substrate influences the concentration of bioactive molecules in the fruiting bodies of P. djamor. Additionally, P. djamor's degradation of agave bagasse residue generates a potential application for agro-industrial residue management at a low cost.

Technological, Biochemical and Microbiological Evaluation of Dehydrated Pleurotus ostreatus Powder for Nutraceutical Applications

Abstract:

Background: Mushroom-based products can serve as superior nutraceuticals in both preventing and alleviati human diseases. Dehydrated powder of Pleurotus ostreatus grown in Cuba has a rich nutritional composition and a large number of therapeutic properties. However, technological parameters (e.g. rheological), as well as biochemical and microbiological quality control standards for its use as a raw material in the manufacture of solid dosage forms with nutraceutical and biopharmaceutical applications have not been established yet.

Objective:

The study aims to determine the technological, biochemical and microbiological quality parameters of dehydrated Pleurotus ostreatus powder.

Method:

Rheological ngproperties (Carr´s index, Hausner´s ratio, angle of repose and flow rate) were determined in seven batches of mushroom powder. Biochemical and microbiological analyses were performed using standard methods. Other physicochemical properties (mean particle size, pH and moisture) were also determined.

Results:

Technical parameters showed a mean particle size of 224.08±7.96 µm, Carr´s compressibility index (23.08-26.58%), Hausner´s ratio (1.30-1.36), angle of repose (36.6-41.90°) and flow rate (3.69-6.93 g cm-2 s-1), typical of materials with poor flowability. Biochemical analyses indicated significant nutraceutical composition: protein (25.0-30.4%), carbohydrate (45-60%), ash (6.1-9.8%), fiber (5-9%), -D-Glucans (1.47-1.61%), iron (21-50 mg/100 g), zinc (3.8-8.0 mg/100 g), and polyphenols (123-160 mg/100 g). Moisture content was ≤3.50% and microbiological analyses were in agreement with ISO standards.

Conclusion:

Dehydrated P. ostreatus powder exhibits good nutraceutical composition and microbiological quality. Technological parameters evidenced poor flow properties, suggesting the need to include excipients to improve the rheological properties for applications as an active ingredient in solid dosage forms for health benefits.

Metabolomic Profiling and Biological Activities of Pleurotus columbinus Quél. Cultivated on Different Agri-Food Byproducts

The genus Pleurotus (Fr.) P. Kumm (Pleurotaceae, Basidiomycota) comprises a cosmopolitan group of mushrooms highly appreciated for their nutritional value and health-promoting benefits. Despite there being many studies about the phytochemical composition of Pleurotus spp., there are very few reports dealing with the phytochemistry, antioxidant and antimicrobial activities of P. columbinus Quél. In this study, a mass spectrometry ultra-performance liquid chromatography mass spectrometry (UHPLC)-QTOF method, coupled with principal component analysis (PCA), was applied to the P. columbinus metabolome in order to investigate the influence of different agri-food residues as growth substrates for P. columbinus cultivation, on the bioactive chemical profile of fruiting bodies and evaluated their potential as antioxidants and antimicrobials. Additionally, a quantitative HPLC-DAD-MS analysis was conducted on phenolic and flavonoid compounds, that could explain, albeit partially, the observed biological effects of P. columbinus extracts. The qualitative metabolic profile identified 97 metabolites, whereas the quantitative HPLC-DAD-MS analysis confirmed the presence of phenolic and flavonoids, in the mushroom extracts, which also showed intrinsic scavenging/reducing and antimicrobial effects. The antibacterial effects were particularly evident against Escherichia coli, whereas Tricophyton and Aspergillus were the dermatophytes more sensitive to the mushroom extracts. The present study supports more in-depth investigations, aimed at evaluating the influence of growth substrate on P. columbinus antimicrobial and antioxidant properties. The extracts from P. columbinus revealed valuable sources of primary and secondary metabolites, thus suggesting potential applications in the formulation of food supplements with biological properties, above all in terms of antioxidant and antimicrobial properties.