Mushroom Protein Research Articles

Structure and functionality of Pleurotus geesteranus protein isolate as a function of pH.

Edible mushroom proteins hold great potential for food applications, but those extracted using the alkaline extraction-acid precipitation method typically exhibit poor solubility in neutral water, with the structural changes during acid precipitation remaining unclear. In this study, Pleurotus geesteranus protein isolate (PGPI) with high water solubility was prepared with alkaline extraction, followed by dialysis and freeze-drying, and the effects of pH on the structural and functional properties of PGPI were systematically investigated. PGPI was enriched in essential and aromatic amino acids, and the molecular weight of bands in the sodium dodecyl sulfate-polyacrylamide gel electrophoresis profile was mainly distributed below 45kDa. The zeta potential of PGPI changed from +16.84 to 17.58mV when the pH increased from 2 to 9, with a pI of 4.3. At pH 7, PGPI showed a size of 232.7nm. Away from pH 7, the particle size of PGPI increased. When the pH decreased from 7 to 2, PGPI exhibited a lower α-helix structure content and a higher β-sheet content and a gradual decrease in fluorescence intensity. In addition, as the pH approached 4, H0 and the content of SS group increased to a peak. These results indicated that lowering the pH induced the development of more ordered protein structure, which could be the primary reason for the poor water solubility of P. geesteranus protein obtained through alkaline extraction and acid precipitation. Additionally, these structural changes result in alterations to its functional properties, including water-holding capacity, oil-holding capacity, foaming capacity, foaming stability, emulsion activity index, and emulsion stability index.

Effects of a Functional Cone Mushroom (Termitomyces fuliginosus) Protein Snack Bar on Cognitive Function in Middle Age: A Randomized Double-Blind Placebo-Controlled Trial.

Background: Due to the rising prevalence of cognitive impairment in the middle-aged and elderly population, combined with consumer demand for functional foods to improve health and well-being. Objective: This study aimed to formulate a functional cone mushroom (Termitomyces fuliginosus) (FCM) protein snack bar and evaluate its amino acid profile, phytochemical contents, biological activity and impact on cognitive function. Methods: A total of 26 middle-aged male and female participants were randomized and divided into placebo, FCM1 and FCM2 groups. Continuous consumption was performed for 6 weeks. Demographic data, body composition, cognitive function and memory were evaluated at baseline and at the end of the study period (6 weeks). Results: The event-related potential (ERP) analysis results showed a significant increase in N100 and P300 amplitude at the Fz location in participants who consumed the functional cone mushroom protein snack bar at a dose of 1 g compared to the placebo group (p = 0.015). Additionally, subjects who consumed the functional cone mushroom protein snack bar at a dose of 2 g showed a significantly increased P300 amplitude and percent accuracy of numeric working memory (p = 0.048) compared to those in the placebo group (p = 0.044). The possible underlying mechanism may involve AChE and MAO suppression activity alongside antioxidant activity. Conclusions: These data suggest that FCM can improve cognitive function and memory and may be considered for use in natural supplementation products with possible health benefits.

Spray dried protein concentrates from white button and oyster mushrooms produced by ultrasound-assisted alkaline extraction and isoelectric precipitation.

In the present study, the optimization of ultrasound-assisted alkaline extraction (UAAE) and isoelectric precipitation (IEP) was applied to white button (WBM) and oyster (OYM) mushroom flours to produce functional spray dried mushroom protein concentrates. Solid-to-liquid ratio (5-15% w/v), ultrasound power (0-900 W) and type of acid [HCl or acetic acid (AcOH)] were evaluated for their effect on the extraction and protein yields from mushroom flours submitted to UAAE-IEP protein extraction. Prioritized conditions with maximized protein yield (5% w/v, 900 W, AcOH, for WBM; 5% w/v, 900 W, HCl for OYM) were used to produce spray dried protein concentrates from white button (WBM-PC) and oyster (OYM-PC) mushrooms with high solids recovery (62.3-65.8%). WBM-PC and OYM-PC had high protein content (5.19-5.81 g kg-1), in addition to remarkable foaming capacity (82.5-235.0%) and foam stability (7.0-162.5%), as well as antioxidant phenolics. Highly pH-dependent behavior was observed for solubility (> 90%, at pH 10) and emulsifying properties (emulsification activity index: > 50 m2 g-1, emulsion stability index: > 65%, at pH 10). UAAE-IEP followed by spray drying increased surface hydrophobicity and free sulfhydryl groups by up to 196.5% and 117.5%, respectively, which improved oil holding capacity (359.9-421.0%) and least gelation concentration (6.0-8.0%) of spray dried mushroom protein concentrates. Overall, the present study showed that optimized UAAE-IEP coupled with spray drying is an efficient strategy to produce novel mushroom protein concentrates with enhanced functional attributes for multiple food applications. © 2024 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Optimization, isolation, identification and molecular mechanisms in B16F10 melanoma cells of a novel tyrosinase inhibitory peptide derived from split gill mushrooms

Hyperpigmentation often arises from an imbalance in melanogenesis, primarily due to the overexpression of tyrosinase (TYR). While the inhibition of TYR presents a common approach to skin whitening, it can lead to undesirable side effects. Thus, there is growing interest in safe and natural alternatives for TYR inhibition. Bioactive compounds and peptides sourced from split gill mushrooms hold promise in this regard. This study aims to optimize the conditions for papain-mediated hydrolysis of split gill mushroom protein to inhibit TYR activity, utilizing response surface methodology (RSM) and central composite design (CCD). Optimal conditions were determined at a temperature of 46.70 °C, a hydrolysis time of 217.09 min, and an enzyme-to-substrate ratio (E/S) of 1.1%. Under these conditions, the resulting hydrolysates exhibited significant TYR inhibition, with an IC50 value of 117.86 μg/mL and a degree of hydrolysis (DH) of 87.97%. Further purification via ultrafiltration and RP-HPLC yielded a peptide, Tyr-Ala-Ser-Ile-Leu-Leu (YASILL or YL-6), identified through LC-Q-TOF-MS/MS, which competitively inhibited TYR. YL-6 demonstrated an IC50 value of 3.97 mM for mono-phenolase activity and 6.75 mM for di-phenolase activity. Molecular docking analysis revealed hydrogen bonds and hydrophobic interactions between TYR and YL-6. Treatment of B16F10 cells with YL-6 across concentrations ranging from 10-3000 μM showed no cytotoxic effects.The inhibition of melanin synthesis was investigated via qRT-PCR along with Western blot in MITF, TYR, TRP-1, and TRP-2. The results obtained in this research may prove significant in guiding the development of commercially viable cosmetic products to whiten the skin.

Proteomics and metabolomic analysis provide new insights into the drying changes of Agaricus sinodeliciosus

Agaricus sinodeliciosus is vulnerable to rotting if not stored properly. Locals in the Qinghai Province often dehydrate them by natural wind drying to prolong their storage period. We used proteomic and metabolomic techniques to elucidate the changes in the mushroom proteins and metabolites when they dry out. Notably, 1775 differential proteins were identified. Metabolic analysis revealed that the drying treatment resulted in 140 upregulated and 19 downregulated differential metabolites; most of the upregulated metabolites were associated with mushroom-specific flavour substances. These metabolites mainly included organic acids, carbohydrates, amino acids, and a small amount of active mercury. Combined proteomic and metabolomic analyses also revealed that the majority of proteins and metabolites were enriched in pathways such as membrane transport, organic acid metabolism, glucose, amino acid metabolism, and lipid and oxide phosphorylation. The results provide new insights into Qinghai mushroom sub-entity drying, which will be helpful in guiding drying processing technologies.

Numerical optimization of drying of white button mushroom (Agaricus bisporus) employing microwave and fluidized bed drying for preparing value added product

The microwave-assisted fluidized bed two-stage novel, energy-efficient drying method was used for Agaricus bisporus drying which can be further utilised for mushroom protein powder, and soup. The effect of microwave heating time (MHT), fluidized bed drying temperature (FBDT), and slice thickness (ST) on rehydration ratio, total colour difference (TCD), and overall acceptability of white button mushroom (WBM) powder was investigated. The optimized values, i.e., 1 min (MHT), 60 °C (FBDT), and 2 mm (ST), were obtained during optimization using design expert software (ver. 13.0.1). The result revealed that MHT, FBDT, and ST affect the responses significantly. TCD was found to be increased while overall acceptability decreased as MHT and FBDT increased. Rehydration is an important criterion for using dry products in curry or soup since they may absorb water. The optimized WBM (O-WBM) powder was used to prepare the soup mix. Out of three formulations (F1, F2, and F3), F3 had a 9 % O-WBM powder score with a maximum mean value for colour, taste, flavor, consistency, and overall acceptability, followed by F2 with a 7 % O-WBM powder. The soup’s composition includes functional ingredients such as garlic, shallots, and milk powder, making it healthier.

Maillard reaction products of hydrolyzed Copyinds comatus protein with various sugar-amino acid combinations: Focusing on their meaty aroma notes and salt reduction abilities

Maillard reaction products (MRPs) of mushroom protein have been shown to present unique flavor properties, but how additional reducing sugar and amino acids manipulate the generation of meaty flavor and the taste traits of MRPs are still open questions. In this study, the Copyinds comatus protein hydrolysates with different reducing sugars (D-ribose and D-xylose) and amino acids (cysteine, methionine, proline, and glutamic acid) were thermally treated. The flavor properties, volatile compounds and taste profiles of the resulting products were comprehensively evaluated using multi-scale flavor analyses techniques. Though the E-nose and E-tongue revealed enriched volatile profiles and taste traits of MRPs than the original hydrolysate, MRPs derived from various sugar-amino acid combinations cannot be well distinguished according to the PCA score plots. The fingerprints by GC-IMS revealed amino acid-specific compounds, including methylpyrazine, hexanol, and isopropyl acetate for methionine-participated MRPs, and ethyl propanoate, cyclohexanone, and 2-butanone for MRPs derived from cysteine. Quantitative results further demonstrated that the methionine-involved MRPs contained significantly higher amounts of sulfur- and nitrogen-containing VOCs than other MRPs, most of which were associated with meat-like odors. Sensory evaluation confirmed that the species of amino acid and reducing sugars made differences in the taste traits, and MRPs prepared from xylose-glutamic acid and xylose-methionine showed outstanding advantages of saltiness and umami taste enhancement. Overall, Copyinds comatus MRPs with methionine are efficient ingredients for the production of meat flavoring, with capacities to compensate for reduced sensory properties of low-sodium food.

New Insights into Interactions between Mushroom Aegerolysins and Membrane Lipids.

Aegerolysins are a family of proteins that recognize and bind to specific membrane lipids or lipid domains; hence they can be used as membrane lipid sensors. Although aegerolysins are distributed throughout the tree of life, the most studied are those produced by the fungal genus Pleurotus. Most of the aegerolysin-producing mushrooms code also for proteins containing the membrane attack complex/perforin (MACPF)-domain. The combinations of lipid-sensing aegerolysins and MACPF protein partners are lytic for cells harboring the aegerolysin membrane lipid receptor and can be used as ecologically friendly bioinsecticides. In this work, we have recombinantly expressed four novel aegerolysin/MACPF protein pairs from the mushrooms Heterobasidion irregulare, Trametes versicolor, Mucidula mucida, and Lepista nuda, and compared these proteins with the already studied aegerolysin/MACPF protein pair ostreolysin A6-pleurotolysin B from P. ostreatus. We show here that most of these new mushroom proteins can form active aegerolysin/MACPF cytolytic complexes upon aegerolysin binding to membrane sphingolipids. We further disclose that these mushroom aegerolysins bind also to selected glycerophospholipids, in particular to phosphatidic acid and cardiolipin; however, these interactions with glycerophospholipids do not lead to pore formation. Our results indicate that selected mushroom aegerolysins show potential as new molecular biosensors for labelling phosphatidic acid.

Neuroprotective mushrooms

Abstract Objectives Alternative medicines commonly supplement or, at times, replace standard medical treatment. One area of increasing attention is disease-modifying medicines for neurodegenerative diseases. However, few such alternatives have been investigated thoroughly with an eye towards understanding mechanisms of action for clinical use. Medicinal mushrooms have important health benefits and pharmacological activities with anti-inflammatory, antioxidant, antibacterial, antiviral, immunomodulatory, digestive, cytoprotective, homeostatic, and neuroprotective activities. Edible mushrooms are known to play roles in preventing age-related diseases. Several studies have revealed that polysaccharides, terpenes, and phenolic compounds are chemical components derived from mushrooms with pharmacological activities. Due to limited effective protocols for mushroom protein extraction for proteomic studies, information about these medicinally related proteins and their biological functions remains enigmatic. Methods Herein, we have performed proteomic studies of two mushroom species Laricifomes officinalis (agarikon) and Grifola frondosa (maitake). Results These studies serve to uncover a foundation for putative proteome-associated neuroprotective processes. The recovered proteins from both species show multiple cell-specific signaling pathways including unfolded protein response, and mitochondrial protein import as well as those linked to BAG2, ubiquitination, apoptosis, microautophagy, glycolysis, SNARE, and immunogenic cell signaling pathways. Conclusions This study uncovered mushroom proteome-associated proteins which serve to better understand the structural and functional properties of mushrooms used as alternative medicines for broad potential health benefits.

Comparative Reports on Pleurotus Sajor-caju Cultivated on Local Wood Wastes in Ibadan Metropolis, Nigeria

Cultivation of Pleurotus species, an Oyster mushroom is now becoming well known due to its taste, medicinal and nutritional values. It is capable of degrading agricultural wastes efficiently and even grows at different temperature ranges. Relatively, Pleurotus species has shorter life span and the fruiting bodies are rarely attacked by pests and diseases unlike the other edible mushrooms. Therefore, the aim of this research is to access the influence of mineral constituents of five local wood wastes (Anogeissus leiocarpa, Pouteria altissima, Vitellaria paradoxa, Cordia milleni and Triplochiton scleroxylon) in Ibadan metropolis on the growth, fruiting body yield and proximate analysis of cultivated oyster mushroom (P. sajor-caju). Data of Carbon/Nitrogen ratio (11.10 – 11.60) found reveal composition of Magnesium (0.035 mg), Potassium (0.053 mEq/l), Manganese (0.0013 mg), Copper (0.00050 g/m3), Iron (0.00275 mol/L), Phosphorus (0.027 mmol/L), Organic carbon (32.10 mg/L C), Organic matter (55.3 t/ha) and total nitrogen (2.77 mg/L) contributed greatly to the high crude protein, fats and ash contents of mushroom cultivated on T. Scleroxylon. However, insignificant contents of sodium (0.2 mg), Calcium (0.2 mmol/L) and Magnesium (0.013 mg) in Pouteria altissima led to the general inadequate performance of (P. sajor-caju) in yields. The fresh mean weight of (P. sajor-caju) was from 8.00 g – 27.53 g. The heaviest weight was obtained from T. scleroxylon followed by V. paradoxa, C. milleni, while Anogeissus leiocarpa gave the lightest weight. Hence, T. scleroxylon will be suggested for cultivating P. sajor-caju because of its positive impact on the yield, crude fibre, and protein content of the experimented mushroom.

Fabrication and characterization of W1/O/W2 double emulsions stabilized with Pleurotus geesteranus protein particles via one-step emulsification

In this study, Pleurotus geesteranus protein isolate (PPI) with low solubility in water was fabricated into nanoparticle (PPIP) that can be uniformly dispersed in pH 7.0 aqueous solution using pH cycle method. PPIP with a zeta potential of −19.21 mV had a mean size of 250.53 nm and two main peaks in particle size distribution profile. This was consistent with the TEM results, which existed both as individual particles and as particle aggregates. The main force responsible for maintaining the structure of protein particles was hydrogen bonding. Interestingly, these protein particles were successfully utilized to fabricate W1/O/W2 double emulsions using one-step homogenous emulsification, and the formation and properties of PPIP-stabilized W1/O/W2 double emulsions were significantly influenced by the protein particle concentration, oil content, and salt concentration in W2 continuous phase. Specifically, higher particle concentration and salt concentration caused a reduction in the number of W1/O droplets and the size of oil droplets. Conversely, an increase in oil content increased the number of W1/O droplets primarily due to the augmentation in the size of oil droplets. The gel strength of double emulsions was enhanced with particle concentration and oil content, as this led to the formation of stronger particle networks and droplet networks. While an opposite phenomenon was found in increasing salt concentration in W2 continuous phase, possibly resulting from the disruption of the ordered gel network. These findings not only provide new food-grade emulsifiers for W1/O/W2 double emulsions, but also broaden the application of edible mushroom proteins in food industry.

Methyl jasmonate differentially and tissue-specifically regulated the expression of arginine catabolism–related genes and proteins in Agaricus bisporus mushrooms during storage

Methyl jasmonate (MeJA)-regulated postharvest quality retention of Agaricus bisporus fruiting bodies is associated with arginine catabolism. However, the mechanism of MeJA-regulated arginine catabolism in edible mushrooms is still unclear. This study aimed to investigate the regulatory modes of MeJA on the expression of arginine catabolism–related genes and proteins in intact and different tissues of A. bisporus mushrooms during storage. Results showed that exogenous MeJA treatment activated endogenous JA biosynthesis in A. bisporus mushrooms, and differentially and tissue-specifically regulated the expression of arginine catabolism–related genes (AbARG, AbODC, AbSPE-SDH, AbSPDS, AbSAMDC, and AbASL) and proteins (AbARG, AbSPE-SDH, AbASL, and AbASS). MeJA caused no significant change in AbASS expression but resulted in a dramatic increase in AbASS protein level. Neither the expression of the AbSAMS gene nor the AbSAMS protein was conspicuously altered upon MeJA treatment. Additionally, MeJA reduced the contents of arginine and ornithine and induced the accumulation of free putrescine and spermidine, which was closely correlated with MeJA-regulated arginine catabolism–related genes and proteins. Hence, the results suggested that the differential and tissue-specific regulation of arginine catabolism–related genes and proteins by MeJA contributed to their selective involvement in the postharvest continuing development and quality retention of button mushrooms.

Effects of Freeze-Thaw Cycles on the Structures and Functional Properties of Clitocybe squamulosa Protein Isolates.

Changes in the functional properties and structures of Clitocybe squamulosa protein isolate (CSPI) in the process of freeze-thaw (F-T) cycles were explored. Remarkable alterations and the reduced content of protein ordered structure were revealed through structural analysis of CSPI after F-T treatments. The surface hydrophobicity and free sulfhydryl content of CSPI first increased and then decreased. However, after the F-T treatments, the carbonyl content of CSPI continued to increase. Similarly, the water holding capacity (WHC), oil holding capacity (OHC), and solubility of CSPI all declined as the number of F-T cycles increased. The foaming properties and emulsifying properties of CSPI were significantly improved and reached maximum values after three F-T cycles. CSPI undergoing two F-T cycles showed the highest digestibility, maximum polypeptide content, and highest DPPH and ·OH-radical-scavenging activities. The ·OH-radical-scavenging activities and reducing power of the gastrointestinally digested CSPI had the highest value after one F-T cycle. Therefore, it has been demonstrated that F-T treatments could be a residue-free and cost-effective tool for improving mushroom protein functional properties.

Effects of Mineral Composition of Different Wood Wastes in Ibadan on Proximate Composition of Lentinus Squarrosulus (Mont.)

Lentinus squarrosulu (Mont.) is one of the cultivated indigenous edible mushrooms that are available in Nigeria. Recently, there has been growing crave to crop wild edible mushroom species that have potential economic values. Mushrooms can be an alternative source of protein especially for commoners in the society. Hence, the objective of this paper is to evaluate the effect of mineral composition of five wood wastes- Triplochiton scleroxylon, Cordia milleni, Vitellaria paradoxa, Pouteria altissima and Anogeissus leiocarpa different wood wastes on L. squarrosulus (Edible Mushroom) cultivation for their consequences on the growth, yield and proximate analysis. Data obtained reveal Carbon/Nitrogen ratio of 11.59, composition of Magnesium (0.035 mg), Potassium (0.053 mEq/l), Manganese (0.0013 mg), Copper (0.00050 g/m3), Iron (0.00275 mol/L), Phosphorus (0.027 mmol/L), Organic carbon (32.10 mg/L C), Organic matter (55.3 t/ha) and total nitrogen (2.77 mg/L) contributed greatly to the high crude protein, fats and ash contents of mushroom cultivated on T. Scleroxylon. However, insignificant contents of sodium (0.2 mg), Calcium (0.2 mmol/L) and Magnesium (0.013 mg) in Pouteria altissima led to the general inadequate performance of L. squarrosulus in yields. The percentage fresh mean weight of L. squarrosulus ranged from 9.13 g – 19.00 g. The highest value was produced by T. scleroxylon followed by P. altissima, V. paradoxa, C. milleni while A. leiocarpa gave the least.

Preparation and Identification of Peptides with α-Glucosidase Inhibitory Activity from Shiitake Mushroom (Lentinus edodes) Protein

The shiitake mushroom is the most commonly cultivated edible mushroom in the world, and is rich in protein. This study aims to obtain the peptides with α-glucosidase inhibition activity from shiitake mushroom protein hydrolysate. The conditions of enzymatic hydrolysis of shiitake mushroom protein were optimized by response surface test. The results showed that the optimal conditions were as follows: the E/S was 3390 U/g, the solid–liquid ratio was 1:20, the hydrolysis temperature and time were 46 °C and 3.4 h, respectively, and the pH was 7. The active peptides were separated by gel filtration and identified by LC-MS/MS analysis and virtual screening. The results indicated that fourteen peptides were identified by LC-MS/MS. Among them, four new peptides (EGEPKLP, KDDLRSP, TPELKL, and LDYGKL) with the higher docking score were selected and chemically synthesized to verify their inhibition activity. The IC50 values of EGEPKLP, KDDLRSP, TPELKL, and LDYGKL for α-glucosidase inhibition activity ranged from 452 ± 36 μmol/L to 696 ± 39 μmol/L. The molecular docking results showed that the hydrogen bond and arene–cation bond were the two major interactions between four peptides and 2QMJ. The hydrogen bonds were crucial to the inhibition activity of α-glucosidase. The results indicate the potential of using the peptides from shiitake mushroom protein as functional food with α-glucosidase inhibition activity.

Influence of the chemical content of sawdust on the levels of important macronutrients and ash composition in Pearl oyster mushroom (Pleurotus ostreatus).

Influence of chemical composition of sawdust on the nutritional profile of oyster mushrooms (Pleurotus ostreatus) has yet to receive significant research attention. This information will help mushroom growers to select specific sawdust for the production of mushroom with desired dietary preferences. This study assessed the influence of the chemical composition of sawdust on the macronutrients and ash content of the pearl oyster mushrooms. The American Standard for Testing Materials and other widely accepted protocols were used to determine the C-N ratio, pH, lignin, hemicellulose and cellulose contents of mixed sawdust from tropical wood species. The study evaluated the fat, crude fibre, crude protein, carbohydrate, and ash content of the oyster mushroom cultivated on the sawdust. Cellulose constituted the largest component of the sawdust (47.82%), followed by lignin (33.29%). The yield of the mushroom (on 0.05 kg of sawdust) ranged from 490.1 to 540.9 g (biological efficiency: 44-50%); the average carbohydrates constituent in the mushroom was 56.28%. pH of the sawdust influenced the crude protein, carbohydrate, fat and ash content of oyster mushrooms (p<0.05) most significantly. The hemicelluloses also had a significant effect (p<0.05) on the mushroom's minerals, fat and crude fiber content. The study revealed that the mushroom producers would likely obtain high protein content using sawdust with low pH (slightly acidic to slightly basic) in the oyster mushroom. Mushrooms grown on substrates, rich in hemicelluloses, had low fat and high crude fiber content.

Bioactive peptides from mushroom proteins

Bioactive peptides from mushroom proteins

Transglutaminase-Catalyzed Glycosylation Improved Physicochemical and Functional Properties of Lentinus edodes Protein Fraction.

Lentinula edodes has high nutritional value and abundant protein. In order to develop and utilize edible mushroom protein, this study was designed to investigate the effects of TGase-catalyzed glycosylation and cross-linking on the physicochemical and functional properties of Lentinus edodes protein fraction. The results showed that within a certain time, glycosylation and TGase-catalyzed glycosylation decreased the total sulfydryl, free sulfydryl, disulfide bond, surface hydrophobicity, β-fold and α-helix, but increased the fluorescence intensity, random coil, β-turn, particle size and thermal stability. The apparent viscosity and the shear stress of the protein with an increase in shear rate were increased, indicating that TGase-catalyzed glycosylation promoted the generation of cross-linked polymers. In addition, the TGase-catalyzed glycosylated proteins showed a compact texture structure similar to the glycosylated proteins at the beginning, indicating that they formed a stable three-dimensional network structure. The flaky structure of proteins became more and more obvious with time. Moreover, the solubility, emulsification, stability and oil-holding capacity of enzymatic glycosylated Lentinus edodes protein fraction were significantly improved because of the proper TGase effects of glycosylation grafting and cross-linking. These results showed that glycosylation and TGase-catalyzed glycosylation could improve the processing characteristics of the Lentinula edodes protein fraction to varying degrees.

Nutritional Quality and Biological Application of Mushroom Protein as a Novel Protein Alternative.

Global concerns about population growth, economic, and nutritional transitions and health have led to the search for a low-cost protein alternative to animal origins. This review provides an overview of the viability of exploring mushroom protein as a future protein alternative considering the nutritional value, quality, digestibility, and biological benefits. Plant proteins are commonly used as alternatives to animal proteins, but the majority of them are low in quality due to a lack of one or more essential amino acids. Edible mushroom proteins usually have a complete essential amino acid profile, meet dietary requirements, and provide economic advantages over animal and plant sources. Mushroom proteins may provide health advantages by eliciting antioxidant, antitumor, angiotensin-converting enzyme (ACE), inhibitory and antimicrobial properties over animal proteins. Protein concentrates, hydrolysates, and peptides from mushrooms are being used to improve human health. Also, edible mushrooms can be used to fortify traditional food to increase protein value and functional qualities. These characteristics highlight mushroom proteins as inexpensive, high-quality proteins that can be used as a meat alternative, as pharmaceuticals, and as treatments to alleviate malnutrition. Edible mushroom proteins are high in quality, low in cost, widely available, and meet environmental and social requirements, making them suitable as sustainable alternative proteins.

A novel mushroom (Auricularia polytricha) glycoprotein protects against lead-induced hepatoxicity, promotes lead adsorption, inhibits organ accumulation of lead, upregulates detoxifying proteins, and enhances immunoregulation in rats.

Lead is a ubiquitous environmental and industrial pollutant. Its nonbiodegradable toxicity induces a plethora of human diseases. A novel bioactive glycoprotein containing 1.15% carbohydrate, with the ability of adsorbing lead and effecting detoxification, has been purified from Auricularia polytricha and designated as APL. Besides, its mechanisms related to regulation of hepatic metabolic derangements at the proteome level were analyzed in this study. Chromatographic techniques were utilized to purify APL in the current study. For investigating the protective effects of APL, Sprague-Dawley rats were given daily intraperitoneal injections of lead acetate for establishment of an animal model, and different dosages of APL were gastrically irrigated for study of protection from lead detoxification. Liver samples were prepared for proteomic analyses to explore the detoxification mechanisms. The detoxifying glycoprotein APL displayed unique molecular properties with molecular weight of 252-kDa, was isolated from fruiting bodies of the edible fungus A. polytricha. The serum concentrations of lead and the liver function biomarkers aspartate and alanine aminotransferases were significantly (p<0.05) improved after APL treatment, as well as following treatment with the positive control EDTA (300 mg/kg body weight). Likewise, results on lead residue showed that the clearance ratios of the liver and kidneys were respectively 44.5% and 18.1% at the dosage of APL 160 mg/kg, which was even better than the corresponding data for EDTA. Proteomics disclosed that 351 proteins were differentially expressed following lead exposure and the expression levels of 41 proteins enriched in pathways mainly involved in cell detoxification and immune regulation were normalized after treatment with APL-H. The results signify that APL ameliorates lead-induced hepatic injury by positive regulation of immune processing, and suggest that APL can be applied as a therapeutic intervention of lead poisoning in clinical practice. This report represents the first demonstration of the protective action of a novel mushroom protein on lead-elicited hepatic toxicity.