Effects of extraction methods on the antioxidant activities of polysaccharides obtained from Flammulina velutipes

Impact of Flammulina velutipes polysaccharide on properties and structural changes of pork myofibrillar protein during the gel process in the absence or presence of oxidation

The present study aimed to investigate the impact of Flammulina velutipes polysaccharide (FVSP) on the rheological properties and structural alterations of myofibrillar protein (MP) and oxidized MP (OMP), utilizing techniques such as rhehometer, fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). In the unoxidized system, the addition of 5.00% FVSP significantly improved (p < 0.05) the storage and loss moduli of the composite gel and promoted the α-helix to β-sheet transformation. These effects enhanced the protein's gel strength and water-holding capacity (WHC). In the oxidation system, 5.00% FVSP had significant effects (p < 0.05) on repair and improvement of the oxidized MP. These effects inhibited the cross-linking aggregation and degradation of the protein. In addition, the addition of FVSP significantly improved the gel properties of MPs after oxidation (p < 0.05), hindered fracture of the protein gel network structure. In summary, polysaccharides have a substantial effect on the functional characteristics of MP, and FVSP could potentially be applied in meat products.

Effects of different extraction methods on the structural and biological properties of Hericium coralloides polysaccharides

In current study, polysaccharides from Hericium coralloides were extracted by heat reflux, acid-assisted, alkali-assisted, enzyme-assisted, ultrasonic-assisted, cold water, pressurized hot water, hydrogen peroxide/ascorbic acid system and acid-chlorite delignification methods, which were named as HRE-P, ACE-P, AAE-P, EAE-P, UAE-P, CWE-P, PHE-P, HAE-P, and ACD-P, respectively. Their physicochemical properties, structural characteristics, and antioxidant activities were investigated and compared. Experimental outcomes indicated notable variations in the extraction yields, chemical compositions, monosaccharide constituents and molecular weights of the obtained nine polysaccharides. HRE-P demonstrated the highest activity against ABTS and OH radicals, CWE-P against ABTS, DPPH, and superoxide radicals, and UAE-P against DPPH radicals. In addition, UAE-P, CWE-P, and HAE-P exhibited better protective effects on L929 cells, when compared to the other obtained polysaccharides. Additionally, correlation analysis indicated that monosaccharide composition and total polyphenol content were two prominent variables influencing the bioactivity of H. coralloides polysaccharides.

Research progress and future development potential of Flammulina velutipes polysaccharides in the preparation process, structure analysis, biology, and pharmacology: A review

In recent years, Flammulina velutipes (F. velutipes) has attracted consequential attention in various research fields due to its rich composition of proteins, vitamins, amino acids, polysaccharides, and polyphenols. F. velutipes polysaccharides (FVPs) are considered as key bioactive components of F. velutipes, demonstrating multiple physiological activities, including immunomodulatory, anti-inflammatory, and antibacterial properties. Moreover, they offer health benefits such as antioxidant and anti-aging properties, which have exceptionally valuable clinical applications. Polysaccharides derived from different sources exhibit a wide range of biomedical functions and distinct biological activities. The varied biological functions of polysaccharides, coupled with their extensive application in functional foods and clinical applications, have prompted a heightened focus on polysaccharide research. Additionally, the extraction, deproteinization, and purification of FVPs are fundamental to investigate the structure and biological activities of polysaccharides. Therefore, this review provides a comprehensive and systematic overview of the extraction, deproteinization, purification, characterization, and structural elucidation of FVPs. Furthermore, the biological activities and mechanisms of FVPs have been further explored through in vivo and in vitro experiments. This review aims to provide a theoretical foundation and guide future research and development of FVPs.

A review on polysaccharide biosynthesis in Cordyceps militaris

Cordyceps militaris (C. militaris) is an edible parasitic fungus with medicinal properties. Its bioactive polysaccharides are structurally diverse and exhibit various metabolic and biological activities, including antitumor, hypoglycemic, antioxidant, hypolipidemic, anti-inflammatory, immunostimulatory, and anti-atherosclerotic effects. These properties make C. militaris-derived polysaccharides a promising candidate for future development. Recent advancements in microbial fermentation technology have enabled successful laboratory cultivation and extraction of these polysaccharides. These polysaccharides are structurally diverse and exhibit various biological activities, such as immunostimulatory, antioxidant, antitumor, hypolipidemic, and anti-atherosclerotic effects. This review aims to summarize the structure and production mechanisms of polysaccharides from C. militaris, covering extraction methods, key genes and pathways involved in biosynthesis, and fermentation factors that influence yield and activity. Furthermore, the future potential and challenges of utilizing polysaccharides in the development of health foods and pharmaceuticals are addressed. This review serves as a valuable reference in the fields of food and medicine, and provides a theoretical foundation for the study of polysaccharides.

Characterization and anticancer effects of extracellular polysaccharide from DHA-producing microalga Crypthecodinium sp. SUN

The Characterization and anticancer effects of extracellular polysaccharide (EPS) from DHA-producing microalga Crypthecodinium sp. SUN were studied in the present research. Results showed that EPS from C. sp. SUN have a molecular weight of 1.118 × 106 g/mol. EPS significantly inhibited the proliferation and migration of LA795 lung adenocarcinoma cells, and the apoptosis rate decreased in a concentration-dependent manner, reached 52 % at 15 mg/mL. C. sp. SUN EPS also significantly decreased reactive oxygen species (ROS) level by over 50 %, superoxide dismutase (SOD) activity by 76 %, and catalase (CAT) activity by 34 % at 10 mg/mL, indicating that EPS may inhibit tumor cell growth instead of killing tumor cells. Additionally, C. sp. SUN EPS suppressed cell proliferation by downregulating the expression of adhesion proteins and cyclin D1 in LA795 cells. In vivo experiments demonstrated that C. sp. SUN EPS inhibited the growth of lung adenocarcinoma tumors without affecting the normal body weight of nude mice. Collectively, the present study showed that C. sp. SUN EPS could be a potential substance for cancer treatment, which provided a research basis for future study on EPS and expanded the application of Crypthecodinium.

Effect of Flammulina velutipes polysaccharides on the physicochemical properties of catfish surimi and myofibrillar protein oxidation during frozen storage

This study investigated the effect of Flammulina velutipes polysaccharides (FVPs) on the myofibrillar protein (MP) oxidation protein and physicochemical properties of catfish surimi during 75 days of frozen storage at -18°C. FVP was added to surimi at 1%, 1.5%, and 2%, respectively; the degree of MP oxidation and the physicochemical properties of the surimi were investigated, and the microstructure of the surimi was observed by scanning electron microscopy (SEM). The results showed that the carbonyl content and the thiobarbituric acid reactive substances (TBARS) in the FVP groups were lower than those in the CK group (the blank surimi). In comparison, the total sulfhydryl content, solubility, and Ca2+-ATPase activity were higher than those in the CK group after 75 days of storage. The addition of FVP significantly increased the water-holding capacity (WHC), gel strength, elastic modulus (G'), and loss modulus (G") of surimi, and made the gel of surimi have stronger continuity and a denser structure. Therefore, FVP has a better cryoprotective effect on surimi. It improves the quality of surimi, decreases MP oxidation, and reduces lipid and water loss during frozen storage. The anti-freezing effect of FVP added at 2% was similar to that of commercial protectants (4% sucrose and 4% sorbitol).

Polysaccharides: potential bioactive macromolecules for Alzheimer's disease

Alzheimer's disease (AD) is one of the leading causes of death and disability. AD is a devastating disease that has caused an overwhelming burden. However, no disease-modified treatment was discovered. The approval of sodium oligomannate (GV-971) in mild-moderate AD patients has attracted great attention to investigate the role of saccharides in AD. Therefore, summarizing and explaining the role of saccharides in AD is urgent and promising. Recent studies showed that polysaccharides (PSs) potentially benefit AD in vitro and in vivo. PSs could alleviate the pathological damage and improve cognitive symptoms via (1) antagonizing the toxicity of abnormal amyloid-beta and tau proteins; (2) attenuating oxidative stress and proinflammation; (3) rebuilding neuroplasticity. PSs exhibit one-multiple pathological hits of AD. However, a thorough chemical investigation is needed for further study.

Basic characterization, antioxidant and immunomodulatory activities of polysaccharides from sea buckthorn leaves

The polysaccharides from Sea buckthorn leaves (SBLPs) were extracted by hot water and purified by DEAE cellulose, then separated into six polysaccharides (SBLP-S) by DEAE-52 column. Six separated polysaccharides were characterized by Ultraviolet Spectroscopy, Infrared Spectrum, High Performance Liquid Chromatographic and Congo red analysis. The antioxidant activity and immunological activity were investigated in vitro. The results revealed that the monosaccharide composition of SBLP-S-1, SBLP-S-2, SBLP-S-3, SBLP-S-5 and SBLP-S-6 contained Man, GlcN, Rib, Rha, GluA, GalA, Glu, Gal, Xyl, Ara and Fuc, among them, rare glucosamine was found. And SBLP-S-4 contained all above components except GlcN and GluA. FT-IR showed that SBLP-S were sulfated polysaccharide containing uronic acid. Molecular weights of SBLP-S were 338.659, 401.305, 599.849, 393.904, 626.895 and 176.862 kDa. The Congo-red test indicated that SBLP-S-2, SBLP-S-4, SBLP-S-5, and SBLP-S-6 had triple helix conformation. Crude polysaccharides had the strong scavenging activities on DPPH radicals, ABTS radicals and hydroxyl radicals. The six polysaccharides had the activity of immune stimulation on RAW264.7 cell. SBLP-S-2 promoted the phagocytosis best and SBLP-S-6 promoted the NO production best. The results suggested that SBLPs could be used as potential antioxidants and immunomodulatory agents in pharmaceutical and functional food fields.

Flammulina velutipes polysaccharide counteracts cadmium-induced gut injury in mice via modulating gut inflammation, gut microbiota and intestinal barrier

Cadmium (Cd), as Group I carcinogen, can induce damage to various organs including the gut. It is of great importance to meet the rising demand for effective therapies against Cd-induced damage and investigate the mechanism. Flammulina velutipes is a popular edible mushroom, despite the well-known health benefits of Flammulina velutipes, little is known about the effect of its polysaccharide (FVP) against CdCl₂-intestinal injury. In this study, a FVP (uronic acid, 5.10 %; degree of methylation, 41.24 %) was produced via hot water extraction (85 °C) and ethanol precipitation. The FVP contained eight major monosaccharides and exhibited good thermal stability at temperatures lower than 139.73 °C. FVP (100 mg/kg b. w., gavage for 4 weeks) alleviated CdCl₂ (1.5 mg/kg b. w., gavage for 4 weeks)-induced intestinal inflammation and apoptosis, intestinal permeability alteration and intestinal barrier disruption. FVP increased the abundance of Bacteroides, whilst decreasing the abundance of Desulfovibrionales and Clostridium. FVP also restored the levels of short-chain fatty acids (SCFAs), including acetic, propionic, isobutyric, butyric, isovaleric and valeric acids. Correlation analysis indicated the interplays among the FVP, gut microbes, SCFAs, intestinal barrier/cells and gut inflammation. FVP enhances the metabolic functions of gut microbiota via functional pathways analyzed by KEGG database. Furthermore, gut microbial transplantation of FVP + CdCl₂ group mice partially alleviated CdCl₂ caused-gut damage. Thus, FVP may be an effective therapeutic agent against CdCl₂-induced gut damage via SCFA-mediated regulation of intestinal inflammation and gut microbiota-related energy metabolism. This study may open a new avenue for developing alternative strategies to prevent CdCl₂-caused injury.

Flammulina velutipes-derived carbon dots for fluorescence detection and imaging of hydroxyl radical

Monitoring hydroxyl radical (•OH) fluctuation is of great importance to study some relative pathological processes and to predict early diagnosis of diseases. Efficient •OH-responsive fluorescent sensors based on carbon dots (CDs) have been reported, but most researches have focused on the new strategies for the synthesis and doping of the CDs. Herein, a kind of biomass CDs (F-CDs) with Flammulina velutipes (F. velutipes) as the carbon source was prepared by a one-step hydrothermal method without any additional modification. The prepared F-CDs have remarkable sensitivity and selectivity and there is a good linear relationship from 0 to 12 μM with a low detection limit of 95 nM for quantitative •OH assay. With excitation-independent emission, favourable biocompatibility and low toxicity, the F-CDs can penetrate cell membranes as •OH-responsive fluorescent sensors to detect intracellular •OH in A549 cells stimulated by phorbol 12-myristate 13-acetate (PMA) and successfully monitor the •OH concentration levels by the corresponding fluorescence change. Given the combined benefits of the green and eco-friendly approach, the F-CDs show promise as novel theranostics tools for early detection and treatment of related diseases.

Recent advances in quality preservation of postharvest golden needle mushroom (Flammulina velutiper)

The golden needle mushroom (Flammulina velutiper) is one of the most productive mushrooms in the world. However, F. velutiper experiences continuous quality degradation in terms of changes in color and textural characteristics, loss of moisture, nutrition and flavor, and increased microbial populations due to its high respiratory activity during the postharvest phase. Postharvest preservation techniques, including physical, chemical and biological methods, play a vital role in maintaining postharvest quality and extending the shelf life of mushrooms. Therefore, in this study, the decay process of F. velutiper and the factors affecting its quality were comprehensively reviewed. Additionally, the preservation methods (e.g., low-temperature storage, packaging, plasma treatment, antimicrobial cleaning and 1-methylcyclopropene treatment) for F. velutiper used for the last 5 years were compared to provide an outlook on future research directions. Overall, this review aims to provide a reference for developing novel, green and safe preservation techniques for F. velutiper. © 2023 Society of Chemical Industry.

Effect of Oral Intake of Flammulina velutipes (Enokitake) on Skin Condition in Healthy Adult Women: A Randomized, Double-Blind, Placebo-Controlled Study on Mental and Physical Health

Nutritional foods are concentrated sources of molecules with a nutritional or physiological effect which contain nutrients. There is a category, “nutricosmetics”, defined as ingestible natural health products that enhance the function and appearance of human skin, nails, and hair. A new variety of Flammulina velutipes (F. velutipes), Oki-Shirayuki 919, was explored to ascertain whether its components have functions of nutricosmetics. We focused on physiological effects for enhancing the human skin condition, such as moisturizing or barrier functions in F. velutipes. A randomized, double-blind, placebo-controlled clinical study was performed between January and March 2022. Among healthy men and women (n = 30) aged 20 to 59 years, the test group (n = 15) took a test product which included F. velutipes dry powder, and the placebo group (n = 15) took a placebo (a similar product in which the F. velutipes dry powder was replaced with plum fruit paste). Since the amount of increase in skin hydration over four weeks in the test group was significantly larger than that in the placebo group, a significant difference between the two groups was observed (p = 0.033). F. velutipe was suggested to have some physiological functions such as improving skin moisture.

Tinospora cordifolia (Willd.) Hook.f. & Thomson polysaccharides: A review on extraction, characterization, and bioactivities

Human awareness of the need for health and wellness practices that enhance disease resilience has increased as a result of recent health risks. Plant-derived polysaccharides with biological activity are good candidates to fight diseases because of their low toxicity. Tinospora cordifolia (Willd.) Hook.f. & Thomson polysaccharides extract from different plant parts have been reported to possess significant biological activity such as anti-oxidant, anti-cancer, immunomodulatory, anti-diabetic, radioprotective and hepatoprotective. Several extraction and purification techniques have been used to isolate and characterize T. cordifolia polysaccharides. Along with hot-water extraction (HWE), other novel techniques like microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE), pulsed electric field (PEF), supercritical-fluid extraction (SFE), and enzyme-assisted extraction (EAE) are used to extract T cordifolia polysaccharides. SFE is a revolutionary technology that gives the best yield and purity of low-molecular-weight polysaccharides. According to the findings, polysaccharides extracted and purified from T. cordifolia have a significant impact on their structure and biological activity. As a result, the methods of extraction, structural characterization, and biological activity of T. cordifolia polysaccharides are covered in this review. Research on T. cordifolia polysaccharides and their potential applications will benefit greatly from the findings presented in this review.

Comparative study on the extraction efficiency, characterization, and bioactivities of Bletilla striata polysaccharides using response surface methodology (RSM) and genetic algorithm-artificial neural network (GA-ANN)

This research established the optimal conditions for alkali-assisted extraction (AAE) of bioactive polysaccharides from Bletilla striata integrated with response surface methodology (RSM) and the genetic algorithm-artificial neural networks (GA-ANN). In comparison with RSM, the ANN model showed a relatively higher determination coefficient in the global output values (RSM: ANN = 0.9270: 0.9742) performing more satisfactorily in the validation. Under the optimum conditions (52 °C; 167 min, and 0.01 mol/L NaOH), the extraction yields, IC₅₀ of ABTS, and FRAP value were 29.53 ± 0.97 %, 3.41 mg/mL, and 39.11 μmol Fe²⁺/g, respectively. The results indicated that BSPs-A was mainly composed of glucose and mannose with small amounts of arabinose, galactose, and galacturonic acid, while possessed a molecular weight of about 305.94 kDa (Mw). The structural characterization of BSPs-A was initially characterized by FT-IR, SEM, and Congo red tests, which indicated that BSPs-A possessed a triple helix conformation of typical Bletilla striata polysaccharides. In addition, BSPs-A exhibited excellent antioxidant activity, which was further confirmed by a series of in vitro antioxidant activity assays including DPPH, ABTS, FRAP, and ORAC. After incubation in the BSA-glucose system for 15 days, BSPs-A showed inhibition of the advanced glycation end products (AGEs) formation for the first time.

Recovery of a hypolipidemic polysaccharide from artificially cultivated Sanghuangporus vaninii with an effective method

In this study, an effective method was developed to extract the polysaccharide from Sanghuangporus vaninii (PFSV) by destroying the cell wall. Box-Behnken design was employed to determine the optimal processing conditions as follows: processing temperature (80°C), processing time (0.81 h) and amount of HCl (1.5 ml). Under these conditions, the yield of PFSV reached 5.94 ± 0.16%. The purified polysaccharide (PFSV-2) was found to be a hetero-polysaccharide with an average molecular weight of 20.377 kDa. The backbone of PFSV-2 was composed of an →6)-α-Galp-(1→ and →2,6)-β-Manp-(1→ and →2)-α-Fucp-(1→ and was branched of t-α-Manp-(1→ at position 2 of residue B. PFSV-2 showed hypolipidemic activity by decreasing lipid accumulation and the levels of total cholesterol and triglycerides in zebrafish larvae. Furthermore, PFSV-2 downregulated the pparg, fasn, and HMGCRb genes and upregulated the pparab and acaca genes. These findings suggested PFSV-2 may be a promising candidate in lipid regulation therapy.

Antioxidant Activities of Natural Polysaccharides and Their Derivatives for Biomedical and Medicinal Applications

Many chronic diseases such as Alzheimer's disease, diabetes, and cardiovascular diseases are closely related to in vivo oxidative stress caused by excessive reactive oxygen species (ROS). Natural polysaccharides, as a kind of biomacromolecule with good biocompatibility, have been widely used in biomedical and medicinal applications due to their superior antioxidant properties. In this review, scientometric analysis of the highly cited papers in the Web of Science (WOS) database finds that antioxidant activity is the most widely studied and popular among pharmacological effects of natural polysaccharides. The antioxidant mechanisms of natural polysaccharides mainly contain the regulation of signal transduction pathways, the activation of enzymes, and the scavenging of free radicals. We continuously discuss the antioxidant activities of natural polysaccharides and their derivatives. At the same time, we summarize their applications in the field of pharmaceutics/drug delivery, tissue engineering, and antimicrobial food additives/packaging materials. Overall, this review provides up-to-date information for the further development and application of natural polysaccharides with antioxidant activities.

Biocompatible and antibacterial Flammulina velutipes-based natural hybrid cryogel to treat noncompressible hemorrhages and skin defects

Hemorrhage, infection, and frequent replacement of dressings bring great clinical challenges to wound healing. In this work, Flammulina velutipes extract (FV) and hydroxyethyl cellulose (HEC) were chemically cross-linked and freeze-dried to obtain novel HFV cryogels (named HFVn, with n = 10, 40, or 70 corresponding to the weight percentage of the FV content), which were constructed for wound hemostasis and full-thickness skin defect repair. Systematic characterization experiments were performed to assess the morphology, mechanical properties, hydrophilic properties, and degradation rate of the cryogels. The results indicated that HFV70 showed a loose interconnected-porous structure and exhibited the highest porosity (95%) and water uptake ratio (over 2,500%) with a desirable degradation rate and shape memory properties. In vitro cell culture and hemocompatibility experiments indicated that HFV70 showed improved cytocompatibility and hemocompatibility. It can effectively mimic the extracellular matrix microenvironment and support the adhesion and proliferation of L929 cells, and its hemolysis rate in vitro was less than 5%. Moreover, HFV70 effectively induced tube formation in HUVEC cells in vitro. The results of the bacteriostatic annulus confirmed that HFV70 significantly inhibited the growth of Gram-negative E. coli and Gram-positive S. aureus. In addition, HFV70 showed ideal antioxidant properties, with the DPPH scavenging rate in vitro reaching 74.55%. In vivo rat liver hemostasis experiments confirmed that HFV70 showed rapid and effective hemostasis, with effects comparable to those of commercial gelatin sponges. Furthermore, when applied to the repair of full-thickness skin defects in a rat model, HFV70 significantly promoted tissue regeneration. Histological analysis further confirmed the improved pro-angiogenic and anti-inflammatory activity of HFV70 in vivo. Collectively, our results demonstrated the potential of HFV70 in the treatment of full-thickness skin defects and rapid hemostasis.

Antioxidant, Anti-Tumour, and Anticoagulant Activities of Polysaccharide from Calocybe indica (APK2)

The initial structural features and in vitro biological study of crude polysaccharides from Calocybe indica (CICP) extracted by hot water followed by ethanol precipitation was investigated. High-performance gel permeation chromatography, HPLC-DAD, UV, IR and NMR spectroscopy, X-ray diffraction, scanning electron microscopy, and Congo red methods were used to determine structural features. The results revealed that CICP is a hetero-polysaccharide with a molecular weight of 9.371 × 10⁴ Da and 2.457 × 10³ Da which is composed of xylose, mannose, fucose, rhamnose, arabinose, galactose, and glucose. The antioxidant activity of CICP was evaluated using radical scavenging activity (three methods), reducing ability (three methods), metal chelating activity, and lipid peroxidation inhibition activity (two methods). It was found that the antioxidant capacity is concentration-dependent and EC₅₀ values were found to be 1.99–3.82 mg/mL (radical scavenging activities), 0.78–2.78 mg/mL (reducing ability), 4.11 mg/mL (metal chelating activity), and 0.56–4.18 mg/mL (lipid peroxidation inhibition activity). In vitro anticoagulant assay revealed that CICP could prolong activated partial thromboplastin time (APTT), thrombin time (TT), but not prothrombin time (PT). CICP exhibited antiproliferative activity on HeLa, PC3, HT29, HepG2, and Jurkat cell lines with IC₅₀ (μg/mL) values of 148.40, 143.60,151.00, 168.30, and 156.30, respectively. The above findings suggested that CICP could be considered a natural antioxidant and cancer preventative.

Polysaccharides from Volvariella volvacea Mushroom: Extraction, Biological Activities and Cosmetic Efficacy

Polysaccharides from Volvariella volvacea (VVP) were investigated for their cosmetic-related activities and in vivo efficacy for use as a multifunctional active cosmetic ingredient. Three different polysaccharide extraction methods, including hot water shaking (HS), microwave-assisted (MA) and ultrasonic-assisted (UA), were used. Extractable yield, polysaccharide contents and biological activities, including antioxidant, anti-tyrosinase and anti-elastase activities, were compared. The polysaccharides from HS provided the highest extraction yield (15.58 ± 0.96% w/w) and the highest beta-glucan content (18.80 ± 0.81% w/w). The HS polysaccharides also possessed the highest inhibitory effects toward lipid peroxidation (IC₅₀ of 0.0378 mg/mL), tyrosinase (51.46 mg KAE/g), and elastase (604.21 ± 73.66 mg EGCG/g). The cytotoxicity of the VVP was determined for safe use. A cosmetic gel cream containing VVP was developed and 0.2% VVP formulation was observed to be the most stable in color. UV protection factors, skin irritation by single patch test, and in vivo efficacy, including skin moisturization, anti-wrinkle and whitening, were measured. The VVP showed no cytotoxicity against human dermal skin fibroblast. The gel cream containing VVP provided less sun protection factor; however, it significantly exhibited the skin benefits of increasing moisture, gross elasticity, net elasticity, and skin firmness. Improvements to skin roughness, scaliness, wrinkles and in melanin content were also depicted gradually along 8 weeks. V. volvacea, therefore, could be a good source for polysaccharides being used as a moisturizing, anti-wrinkle, and whitening agent in cosmetic preparations.

Characteristics of Mulberry Leaf Powder Enriched With γ-Aminobutyric Acid and Its Antioxidant Capacity as a Potential Functional Food Ingredient

To improve the functional properties of mulberry leaves, γ-aminobutyric acid (GABA) enrichment treatments were applied. The results showed that the combined treatment of sodium glutamate immersion, cold shock, and anoxic significantly increased the GABA content. HPLC analysis displayed that the quantity of some active phenolics was significantly increased after the treatment. The GABA-enriched mulberry leaf powders were subsequently prepared, and it was found that as the particle size decreased, their water and oil holding capacity and their swelling power decreased, while the angle of repose increased. The dissolution rate of GABA and total phenolics increased as the particle size decreased. Optical observations and SEM results revealed that the fiber structures of the particles were gradually destroyed as the particle size decreased. Further, FTIR analysis showed that the active compounds in the powders were not destroyed. M400 and M140 powder showed the maximum DPPH radical scavenging ability and AGEs inhibition capacity, respectively. Additionally, adding the powders effectively alleviated the staling of bread without any significant effect on taste.

The structure-activity mechanism of the changes in the physicochemical properties of Flammulina velutipes polysaccharides during ultrasonic extraction

BACKGROUND

The high yield of ultrasonic extraction has been widely studied. However, the effects of ultrasound on the properties of products has generally been ignored. In this study, the structural characteristics, rheological properties, and thermal stability of Flammulina velutipes polysaccharides (FVPs) under different ultrasonic power (200, 600, 1000 W) and time (10, 20, 30 min) were investigated to explore the effects of ultrasonic extraction on FVPs and the structure-physicochemical properties relationship. The ultrasonic intensity at the corresponding rated power was also measured.

RESULTS

The results showed that the molecular weight, particle size, and zeta potential of FVPs decreased as the ultrasonic intensity or time increased. The galactose, mannose, and fucose contents were increased, but the glucose content was decreased by ultrasonic extraction. Viscosity and weak gel strength were positively correlated with molecular weight. Thermal degradation enthalpy was positively correlated with the galactose and fucose contents.

CONCLUSIONS

Ultrasound reduced the viscosity and gel strength of FVPs by breaking the polysaccharide chain and improving the galactose and fucose contents, which improved the thermal stability of FVPs. This work provides a theoretical basis for the development of FVP foods with a clear structure-function relationship, which makes it possible to directionally produce FVPs by adjusting ultrasonic parameters during extraction. © 2021 Society of Chemical Industry.

The Effect of Flammulina velutipes Polysaccharide on Immunization Analyzed by Intestinal Flora and Proteomics

Proteomics and intestinal flora were used to determine the mechanism of immune modulatory effects of Flammulina velutipes polysaccharide on immunosuppressed mice. The results showed that compared with the model group, F. velutipes polysaccharide could increase thymus and spleen indices and improve thymus tissue structure in mice; IL-2 and IL-4 contents were significantly increased and IL-6 and TNF-α contents were significantly decreased; serum acid phosphatase (ACP), lactate dehydrogenase (LDH) and total antioxidant capacity (T-AOC) activities were increased (P < 0.05); in the liver, superoxide dismutase (SOD) and catalase (CAT) activities were increased (P < 0.001), while malondialdehyde (MDA) content was decreased (P < 0.001). Proteomics discovered that F. velutipes polysaccharides may exert immune modulatory effects by participating in signaling pathways such as immune diseases, transport and catabolism, phagosomes and influenza A, regulating the immune-related proteins Transferrin receptor protein 1 (TFRC) and Radical S-adenosyl methionine domain-containing protein 2 (RSAD2), etc. Gut microbial studies showed that F. velutipes polysaccharides could increase the abundance of intestinal flora and improve the flora structure. Compared to the model group, the content of short-chain fatty acids (SCFAs) and the relative abundance of SCFA-producers Bacteroides and Alloprevotella were increased in the F. velutipes polysaccharide administration group, while Lachnospiraceae_NK4A136_group and f_Lachnospiraceae_Unclassified decreased in relative abundance. Thus, F. velutipes polysaccharide may play an immunomodulatory role by regulating the intestinal environment and improving the balance of flora.

Physicochemical properties, antioxidant activities and α-glucosidase inhibitory effects of polysaccharides from Evodiae fructus extracted by different solvents

In this study, polysaccharides from Evodiae fructus were extracted by water, 0.5 M HCl, 0.5 M NaOH, water + 0.5 M HCl and water + 0.5 M NaOH, which were named as ERP-W, ERP-AC, ERP-AK, ERP-W-AC and ERP-W-AK, respectively. Their physicochemical properties, antioxidant activities and α-glucosidase inhibitory effects were investigated and compared. Physico-chemical analysis showed that they were acidic heteropolysaccharides, which had α- and β-configurations. ERP-W, ERP-AK and ERP-W-AK were mainly composed of Rha, Ara, Gal, Glc and Gal-UA, while ERP-AC and ERP-W-AC were dominantly made up of Rha, Gal and Gal-UA. ERP-AK had the highest yield (24.5%) and the best thermal stability, ERP-AC and ERP-W-AC showed better homogeneity and lower molecular weight (83.6 and 41.6 kDa), and ERP-W possessed the highest neutral sugar content (50.7%) and molecular weight. Biological evaluation indicated that ERP-W, ERP-AK and ERP-W-AK had relatively stronger antioxidant activities, including ABTS, DPPH, OH and O₂^- radicals scavenging activities, Fe²⁺ chelating ability and α-glucosidase inhibitory effects. Moreover, these actions were considerably related to their physicochemical properties especially monosaccharide composition and molecular weight. Therefore, polysaccharides extracted by water and alkaline solvents from Evodiae fructus could be developed as promising natural antioxidants and α-glucosidase inhibitors in the food and medicine industries.

Nutrient profiles, functional compositions, and antioxidant activities of seven types of grain fermented with Sanghuangporus sanghuang fungus

Sanghuangporus sanghuang (SS) is a rare medicinal polypore fungus that grows solely on Morus trees. In this study, seven grains (oats, barley, millet, rice, buckwheat, corn, and coix seed) were used as solid substrates for SS fermentation and characterized in their nutrition, functional composition, and antioxidant activities. After fermentation, the nutrient compositions of crude protein (F 1,41 = 111.1, P < 0.01), soluble protein (F 1,41 = 595.7, P < 0.01), soluble sugar (F 1,41 = 51.4, P < 0.01) and ash (F 1,41 = 227.3, P < 0.01) increased significantly. Oats were one of the best grains for SS fermentation, SS-Oat produced 6.23 mg QE/g polyphenols, 21.8 mg rutin/g flavonoids, and 2.3% triterpene. In addition, the antioxidant capacities of the seven grains all increased. Principal component analysis analysis shows that the antioxidant properties of the grains were similar after SS fermentation. The changes of antioxidant activity due to SS fermentation were corrected with corresponding grain and remarked as ΔT-AOC/ABTS+/DPPH/DNAp, that was correlated to part of changes in polyphenol, carotenoid, triterpenoids, and flavonoid contents. In summary, oats have the greatest potential for use as a fermentation substrate for health food development.

Optimization of an ultrasonic-assisted aqueous two-phase extraction method for four flavonoids from Lysionotus pauciflorus

An effective approach to extracting four flavonoids (lysioside C, nevadensin-7-sambubioside, ikarisoside B, and nevadensin) from Lysionotus pauciflorus using ultrasonic-assisted aqueous two-phase extraction (UAATPE) technology was studied. Ethanol/K₂HPO₄ system was selected and the influence of several important parameters, including composition of the aqueous two-phase system (ATPS), extraction temperature and time, particle size, and solvent to material ratio, were investigated by single factor experimentss. Then three key parameters (ethanol concentration, solvent to material ratio and extraction temperature) were further optimized by response surface methodology (RSM). The optimal process was that 1 g 120 mesh herb powders were extracted with 45 g ATPS (made of 30% ethanol/18% K₂HPO₄) in 43 °C for 30 min, and yields of four flavonoids could reach 2.56, 2.06, 3.62, and 6.28 mg/g, respectively. Compared with ultrasonic-assisted extraction (UAE) in three conventional solvents (water, ethanol and 60% ethanol), the UAATPE displayed comparatively higher extraction capability. Therefore, UAATPE in ethanol/K₂HPO₄ system could be an alternative technology for integrated extraction of the flavonoids from L. pauciflorus.

Plant/algal polysaccharides extracted by microwave: A review on hypoglycemic, hypolipidemic, prebiotic, and immune-stimulatory effect

Microwave-assisted extraction (MAE) is an emerging technology to obtain polysaccharides with an extensive spectrum of biological characteristics. In this study, the hypoglycemic, hypolipidemic, prebiotic, and immunomodulatory (e.g., antiinflammatory, anticoagulant, and phagocytic) effects of algal- and plant-derived polysaccharides rich in glucose, galactose, and mannose using MAE were comprehensively discussed. The in vitro and in vivo results showed that these bioactive macromolecules with the low digestibility rate could effectively alleviate the fatty acid-induced lipotoxicity, acute hemolysis, and dyslipidemia status. The optimally extracted glucomannan- and glucogalactan-containing polysaccharides revealed significant antidiabetic effects through inhibiting α-amylase and α-glucosidase, improving dynamic insulin sensitivity and secretion, and promoting pancreatic β-cell proliferation. These bioactive macromolecules as prebiotics not only improve the digestibility in gastrointestinal tract but also reduce the survival rate of pathogens and tumor cells by activating macrophages and producing pro-inflammatory biomarkers and cytokines. They can effectively prevent gastrointestinal disorders and microbial infections without any toxicity.

Alternative of Phosphate by Freeze- or Oven-Dried Winter Mushroom Powder in Beef Patty

This study investigated freeze- or oven-dried winter mushroom powder (FDP or ODP, respectively) as an alternative to phosphate in beef patties. The beef patties were prepared with four treatments: no addition of phosphate and winter mushroom (control), addition of 0.3% sodium pyrophosphate (BP), addition of 1% FDP (BFW), and addition of 1% ODP (BOW). The pH of FDP and ODP was 6.73, and 7.00, respectively. FDP and ODP contained phenolic compound at a level of 3.50 and 5.45 g gallic acid equivalent/kg, respectively. The cooking loss of beef patties was the highest in the control and lowest in BP (p<0.05). BFW had lower cooking loss than the control (p<0.05), and BOW showed similar cooking loss as that of the control (p>0.05). Inhibition of lipid oxidation was found in BP and BOW as compared with control (p<0.05). BFW was similar to the control in terms of the degree of lipid oxidation (p>0.05). BOW showed lower L* and higher a* values than those of the control, BP and BFW (p<0.05). Texture properties such as hardness, springiness, cohesiveness, gumminess, and chewiness were the highest in BP (p<0.05). A slight increase in hardness and springiness was observed in BOW compared to those of the control (p<0.05). The results showed that FDP and ODP did not exhibit all the properties of phosphate in beef patties. Therefore, FDP and ODP can be used for partial substitution of phosphate in beef patties.

Antioxidant Activity and Biocompatibility of Fructo-Polysaccharides Extracted from a Wild Species of Ornithogalum from Lebanon

The present study aims to investigate the properties of biopolymers extracted from a Lebanese onion non edible plant. The extraction was performed under mild conditions by varying the percentage of ultra-sound (US) treatment duration to a total extraction time of 30 min (0, 50, 100% US). The extracts were characterized using FTIR, SEC, GC-MS, TGA, and DSC analyses. The composition of the extracts was determined from the total carbohydrate content and protein content measurements. The thermal analyses indicate that all samples have high thermal stability. The antioxidant activities of the extracts were investigated, using β-carotene bleaching, scavenging activity of ABTS, metal chelating ability, and total antioxidant activity tests. The results indicate that the 50% US treatment leads to the best antioxidant activity. Biocompatibility of the extracts was evaluated using hemolysis and cytotoxicity assays. The results showed that 0 and 50% US samples are not toxic to human cells, in contrary to 100% US.

Multi-Frequency Ultrasonic Extraction of Anthocyanins from Blueberry Pomace and Evaluation of Its Antioxidant Activity

Background

A large amount of blueberry pomace is discarded and wasted.

Objective

To make full use of blueberry pomace and extract anthocyanins.

Method

Multi-frequency ultrasound was used to extract anthocyanins from blueberry pomace. The effects of different extraction conditions on the anthocyanin yields were studied. The antioxidant activity of anthocyanins was evaluated, and the main anthocyanin components were identified by HPLC-electrospray ionization (ESI)-MS/MS.

Results

The optimal anthocyanin extraction conditions were as follows: dual-frequency ultrasound of 40 + 80 kHz, ultrasonic power of 350 W, extraction temperature of 50°C, and extraction time of 40 min. Compared with single frequency (25 kHz) and tri-frequency ultrasound (25 + 40 + 80 kHz), the anthocyanin yield with dual-frequency ultrasound increased by 15.26% and 5.45% respectively. Furthermore, the antioxidant activities (DPPH, hydroxyl radical scavenging ability, and reducing power) of anthocyanins extracted with dual-frequency ultrasound were all higher than those without ultrasound. Seven kinds of anthocyanins were identified by HPLC-ESI-MS/MS.

Conclusions

Dual-frequency ultrasound had a higher extraction yield than single frequency ultrasound, tri-frequency ultrasound, and no ultrasound.

Highlights

Dual-frequency ultrasonic technology provides an effective approach for improving the extraction yield of anthocyanins from blueberry pomace.

Advances in the extraction, purification, structural-property relationships and bioactive molecular mechanism of Flammulina velutipes polysaccharides: A review

With the further research in recent years, Flammulina velutipes (F. velutipes), an edible mushroom, has great application value in many fields. As one of the main bioactive components in F. velutipes, polysaccharide has a series of functions such as anti-oxidation, immune regulation, anti-inflammation, liver protection, anti-tumor, anti-hyperlipidemia and so on. In this paper, the current progress in the extraction, purification, structural characteristics and bioactivities of F. velutipes polysaccharides (FVPs) were reviewed. Meanwhile, the structural-property relationships of FVPs were further discussed. In addition, based on in vitro and in vivo experiments, the possible mechanisms of bioactivities of FVPs were summarized. In order to understand FVPs more comprehensively, the application status and the future research work of FVPs were also introduced. Finally, we hope that our research can provide a reference for further research and development of FVPs.

Effects of ultrafine grinding on physicochemical, functional and surface properties of ginger stem powders

BACKGROUND

Ginger stem (GS) is a by-product of ginger processing. It is not directly edible as a feed or food, which leads to it being discarded as waste or burned. Accordingly, it is very important to develop new functional products in the food or feed industry as a result of high nutritional and medicinal values. In the present study, the structures and physicochemical properties of GS powders of different sizes were evaluated after ultrafine grinding by a vibrating mill.

RESULTS

The ultrafine powders exhibited a smaller particle size and uniform distribution. Higher values in bulk density (from 1.07 ± 0.06 to 1.62 ± 0.08 g mL-1 ), oil holding capacity (from 3.427 ± 0.04 to 4.83 ± 0.03 g mL-1 ), and repose and slide angles (from 42.33 ± 1.52 to 54.36 ± 1.15° and 33.62 ± 0.75 to 47.27 ± 1.34°, respectively) of ultrafine GS powders were exhibited compared to coarse powders. With a reduced particle size, the solubility of ultrafine powders increased significantly (P < 0.05), whereas the water holding and swelling capacities decreased with a reduced particle size and then increased. Fourier transform infrared spectroscopy analysis showed that ultrafine grinding did not damage the main cellular structure of GS powder. The reduction of fiber length and particle size in GS was observed by light microscopy and scanning electron microscopy. The X-ray diffraction patterns demonstrated the crystallinity and the intensity of the peak in superfine GS powders.

CONCLUSION

The present study suggests that ultrafine grinding treatments influence the structures and physicochemical properties of GS powders, and such changes would improve the effective utilization of GS in the food or feed industry. © 2020 Society of Chemical Industry.

Green fabrication of seedbed-like Flammulina velutipes polysaccharides-derived scaffolds accelerating full-thickness skin wound healing accompanied by hair follicle regeneration

A novel seedbed-like scaffold was firstly fabricated by the "frozen sectioning" processing method using Flammulina velutipes as a raw material. The Flammulina velutipes polysaccharides scaffold is composed of a natural structure imitating the "ground" (connected and aligned hollow tubes with porous walls). Meanwhile, its biologically active components include polysaccharides and proteins, mimicking the "plant nutrition" in the seedbed. To further optimize the ground and nutrition components, Flammulina velutipes polysaccharides-derived scaffolds (FPDSs) were fabricated via the treatment of original Flammulina velutipes polysaccharides scaffold (labeled FPS) by NaOH, cysteine (labeled as FPS/NaOH, FPS/Cys, respectively). FPDSs were characterized by SEM, FTIR, XRD, water absorption and retention, and mechanical evaluations. From the results, FPS/NaOH and FPS/Cys lost the characteristic big tubes of original strips and had higher water absorption capacities comparing to FPS. Simultaneously, FPS/NaOH had better ductility, FPS/Cys had showed increased stiffness. Biological activities of FPDSs were tested against different types of bacteria exhibiting excellent anti-bacterial activity, and FPS/NaOH and FPS/Cys had dramatically higher anti-bacterial activity than FPS. The cytocompatibility of FPDSs was evaluated utilizing mouse fibroblast cell line (L929), and all FPDSs showed good cytocompatibility. The FPDSs were further applied to a rat full-thickness skin wound model, and they all exhibited obviously accelerated re-epithelialization, among which FPS/NaOH showed the greatest efficiency. FPS/NaOH could shorten the wound-healing process as evidenced by dynamic alterations of the expression levels of specific stagewise markers in the healing areas. Similarly, FPS/NaOH can efficiently induce hair follicle regeneration in the healing skin tissues. In summary, FPDSs exhibit potential functions as seedbeds to promote the regeneration of the "seed" including hair follicles and injured skin, opening a new avenue for wound healing.

Screening active fractions from Pinus massoniana pollen for inhibiting ALV-J replication and their structure activity relationship investigation

The objective was to identify the active fractions of polysaccharide against replication of ALV-J and elucidate their structure activity relationship. The optimal extraction conditions were extracting temperature 90℃, pH 9 and the ratio of liquid to solid 30:1. Under these conditions, extraction yield of total polysaccharide was 6.5 % ± 0.19 %. Total polysaccharide was then purified by DEAE-52 cellulose and Sephadex G-200 gel. Three fractions, PPP-1, PPP-2, and PPP-3, were identified with molecular weight of 463.70, 99.41, and 26.97 kDa, respectively. Three polysaccharide fractions were all composed of 10 monosaccharides in different proportions. Compared with PPP-1, which was mainly composed of glucose, PPP-2 and PPP-3 contained a higher proportion of galactose, glucuronic acid and galacturonic acid. The Congo red assay indicated that the PPP-2 may have a triple helical structure, while PPP-1 and PPP-3 were absent. In vitro assay showed that there was no significant cytotoxicity among the polysaccharide fractions under the concentration of 800 μg mL^-1 (P > 0.05). The antiviral test showed that PPP-2 had the strongest activity, indicating PPP-2 was the major antiviral component. The structure-activity relationship showed that the antiviral activities of polysaccharide fractions were affected by their monosaccharide composition, molecular weight, and triple helical structure, which was a result of a combination of multiple molecular structural factors. These results showed that the PPP-2 could be exploited as a valued product for replacing synthetic antiviral drugs, and provided support for future applications of polysaccharide from Pinus massoniana pollen as a useful source for antiviral agent.

Using Flammulina velutipes derived chitin-glucan nanofibrils to stabilize palm oil emulsion:A novel food grade Pickering emulsifier

We herein report chitin-glucan nanofibrils from edible mushroom Flammulina velutipes (CGNFs) as a novel stabilizer for palm oil Pickering emulsion (o/w, 30:70, v:v). Generally, these CGNFs being composed of glucose and glucosamine, are threadlike with 4.9 ± 1.2 nm wide and 222.6 ± 91.9 nm long. They were easily absorbed on the oil-water interface to form a compact layer around the oil droplets referring to Pickering emulsion. This emulsion presented shear-thinning and gel-like behaviors, wherein CGNFs concentration had a profound influence on the emulsion volume, droplet size, and stabilization index. Moreover, CGNFs showed an ability to stabilize the emulsion with a minimum of surface coverage approximately 30%. It indicated that moderate concentration of NaCl improved the emulsification effect, and the emulsion were stable in a large range of pH. These CGNFs are easy to prepare, eco-friendly and sustainable, which provides a potential for large-scale application of Pickering emulsion in food and nutraceuticals fields.

Optimization of ultrasonic-assisted extraction of polysaccharides from purple glutinous rice bran (Oryza sativa L.) and their antioxidant activities

Purple glutinous rice bran (Kum Doi Saket rice (KUM)) contains high content of edible polysaccharides and anthocyanins and has an excellent antioxidant activity. This research aimed to optimize the extraction of crude polysaccharides from defatted purple glutinous rice bran using an ultrasonic-assisted extraction (UAE) and compared with a hot water extraction (HWE). Results showed that optimal extraction condition was as follows: a defatted rice bran to water ratio of 1:20 w/v, extraction temperature and time of 70 °C for 20 min. Under the optimal extraction condition, the yield of polysaccharide of UAE (4%) was significantly higher than that obtained from the HWE (0.8%). Additionally, antioxidant activities of extracted polysaccharide including IC₅₀ value DPPH, IC₅₀ value ABTS, and FRAP value were 1.09 mg/mL, 2.80 mg/mL and 197 µM Fe²⁺/g, respectively. It is suggested that the UAE process is promising method to decrease the processing time and to enhance extracted polysaccharide yields by 4 times.