Extracting Polysaccharides and β-Glucans from Medicinal and Edible Mushrooms: Advanced Extraction Technologies

Abstract: What This Review Covers

In recent years, polysaccharides extracted from mushrooms — and β-glucans in particular — have become a focus of research and industrial interest owing to their biological properties, such as antioxidant activity, activity studied in the context of tumor cells, and their ability to modulate the immune system. To recover these bioactive components, advanced extraction technologies have been developed, including ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE), enzyme-assisted extraction (EAE), ultrasonic-microwave synergistic extraction (UMSE), subcritical water extraction (SWE), pulsed electric field-assisted extraction (PEFAE), aqueous two-phase extraction (ATPE), and other combined methods. The article provides background on the use of mushrooms and details the structural characteristics and biological activities of these polysaccharides. It then discusses the latest developments in extraction technologies, including their strengths and limitations, and describes their underlying mechanisms. It concludes with a critical comparison of the different extraction techniques and offers an outlook on the future of the field.

Introduction: Edible and Medicinal Mushrooms as a Source of Bioactive Compounds

Mushrooms have long been regarded as culturally significant: the Romans called them “food of the gods,” and the ancient Greeks believed they gave strength to warriors. Since then, a diverse range of mushrooms — such as the common button mushroom (Agaricus bisporus), shiitake (Lentinula edodes), oyster mushrooms (Pleurotus, especially Pleurotus ostreatus), enoki (Flammulina velutipes), wood ear (Auricularia auricula-judae) and maitake (Grifola frondosa) — have been part of the human diet for their nutritional and culinary value. Today, as awareness of healthy eating grows, mushrooms have become even more popular, thanks to their content of essential nutritional components such as polysaccharides, polyphenols, proteins, niacin, potassium, riboflavin, selenium and vitamin D, as well as dietary fiber. They are gluten-free, low in calories, low in fat, and low in simple sugars and sodium. In addition, mushroom extracts are incorporated into food products such as frozen yogurt, fruit juice and soy milk to create nutrient-rich products.

Beyond their role as a food source, in Chinese culture mushrooms were traditionally regarded as an “elixir of life” and were used within traditional Asian folk medicine for hundreds of years. To round out the picture of their cultural and historical importance, it is worth telling the story of the “Iceman,” also known as “Ötzi,” who lived about 5,300 years ago. He was found remarkably well preserved in the ice of the Alps, making him one of the oldest and best-preserved human bodies ever discovered. Examining the contents of his pouch and gear, researchers found that Ötzi carried mushrooms in a leather net. Some were tinder fungus (Fomes fomentarius), known for its use as a fire-starter and, at times, in traditional remedies; others were birch polypore (Piptoporus betulinus), traditionally valued for various uses. The presence of these mushrooms illustrates the broad knowledge and early application of fungi among ancient cultures for a variety of purposes.

Polysaccharides and β-Glucan: Structure and Role

Polysaccharides are long, complex carbohydrate chains made up of neutral sugars and/or uronic-acid monomers, held together by glycosidic bonds. They are involved in a range of biological processes, such as embryonic development and cellular defense against infection by viruses and bacteria. Mushrooms contain many types of polysaccharides, including heteropolysaccharides rich in fucose, galactose, mannose and xylose, but the most common are glycogen-like glucans that serve as storage components. The structural polysaccharides of the mushroom cell wall are composed of cellulose or chitin, together with a matrix-like structure made of α-glucans, β-glucans and glycoproteins. β-glucans of mushroom origin are the most extensively studied because of the structural differences between them and polysaccharides of bacterial or plant origin. They consist mainly of a (1→3)-β-D-glucose main chain with branching, usually at the O-6 position, with β-D-glucopyranose units or other oligosaccharides.

Certain polysaccharides such as lentinan from Lentinula edodes and schizophyllan from Schizophyllum commune have been recognized as immunoceuticals (immune-modulating preparations) in countries such as China, Japan and Korea. It is important to note that lentinan and schizophyllan are isolated, standardized compounds used as prescription drugs in those countries, and they are not identical to the whole-mushroom extract sold as a dietary supplement. Because their structural characteristics and biological activities vary significantly according to the mushroom source, it becomes important to understand their potential use across different fields.

Biological Activity of Mushroom Polysaccharides

Polysaccharides native to mushrooms have a meaningful influence on health as bioactive components, acting as “biological response modifiers.” These properties — studied mostly in preclinical research (in the laboratory and in animal models) and not constituting a therapeutic indication — include antioxidant activity, activity studied in the context of tumors, and activities that have been examined in relation to inflammation, coagulation, fatigue, blood-sugar balance, liver protection, blood pressure, immune modulation, and cholesterol and body-fat reduction. Some studies also report that these polysaccharides interact with and bind to surface receptors of tumor cells and, in some models, are associated with their apoptosis.

The physicochemical characteristics of these polysaccharides allow them to bind to various cell receptors, and so they are studied in the context of different conditions, including cancer. Preliminary laboratory studies (in vitro) have shown that polysaccharides from certain mushrooms inhibited the proliferation of tumor cells in culture, including lung, liver, cervical and colon cancer cells. These are cellular and preclinical findings only, and they do not constitute evidence of therapeutic efficacy in humans. In fact, molecular weight, monosaccharide composition, water solubility, structure and degree of branching have been found to decisively influence their biological activity. For example, branched β-(1→3)/(1→6)-glucans, present at high levels in certain mushrooms, have shown significant biological potential in cholesterol clearance and in the regulation of the immune response, when studied in the context of their effect on the immune system.

Obtaining high-quality polysaccharides from mushrooms requires a thorough, meticulous extraction process involving several stages of isolation and purification. The process begins with pretreatments, in which fat is removed using organic solvents, along with an alcohol treatment to remove contaminants and unwanted components.

Advanced Extraction Technologies: Ultrasound, Microwave and Enzymes

Ultrasound-assisted extraction (UAE) offers four key advantages:

1. Improved extraction efficiency — the energy released from the collapsing bubbles breaks down the mushroom cell walls and increases the surface area available for contact between the bioactive component and the solvent, thereby improving extraction efficiency.
2. Time savings — ultrasound-assisted extraction processes take place much faster than conventional extraction methods, reducing the time needed to release the components from the organic material.
3. Energy savings — the shear force and hydrodynamic forces applied during the extraction reduce the need for heating or chemicals, which lowers energy use.
4. Preservation of the bioactive components — the use of ultrasound reduces the likelihood of thermal or chemical degradation of the bioactive components during extraction, which helps preserve their potential.

Overall, ultrasound-assisted extraction is a highly useful tool in the development and manufacture of dietary supplements and nature-based products from mushrooms, while maintaining high standards of quality and efficiency.

A further complementary approach is combining more than one extraction method. For example, the triple-extraction method (Triple Extract) combines several extraction stages to release a broad range of components. The quality of the extract and its β-glucan content can be verified through our transparency page and our lab testing (COA).

1. Microwave-assisted extraction (MAE) — requires a very short processing time, under half an hour, making it effective and fast. Microwaves help the heat penetrate quickly and effectively into the mushroom matrix, rapidly releasing the bioactive components.
2. Aqueous two-phase extraction (ATPE) — operates at room temperature, the lowest among the methods, which leads to the least thermal degradation of the bioactive components. ATPE also allows high selectivity in separating the various components through the use of soluble and insoluble solvents.
3. Subcritical water extraction (SWE) — carried out at high pressure (> 10 MPa) and extreme temperatures (≥ 200°C), which enable efficient release of thermally stable components. However, the high temperature and pressure may lead to degradation or alteration of some components.
4. Enzyme-assisted extraction (EAE) — operates at moderate temperatures (50-60°C), leading to relatively low degradation and allowing better preservation of the biological activity of the components.

The choice of extraction method depends on the type of components to be released, the physical and chemical properties of the raw material, and the specific needs of the process, taking into account the different effects each technique has on the final product.

Conclusions: Why Extraction Quality Matters

The conclusions of the review are as follows:

1. The importance of efficient extraction: improvements in extraction technologies make it possible to maximize the use of the bioactive components in mushrooms, leading to products with high added value for health and for nature-based products.
2. The need to match the extraction method: different methods suit different goals and different types of mushroom, and it is important to select the most appropriate method in order to preserve the bioactive properties while minimizing damage to the components.
3. Developing new technologies: continued development and innovation in extraction is expected to yield methods that are more efficient and more economical in energy and cost.
4. Environmental and energy effects: assessing the environmental and energy impact of extraction technologies is important, and efforts should be made to minimize environmental harm during the extraction processes.
5. The impact of research on industry: research developments in this field can lead to commercial production of bioactive components, opening new markets and improving existing manufacturing technologies.

Ultimately, all of these strengthen the standing of mushrooms as a source of bioactive components studied for their potential to support health, while contributing to the health and nature-based-product industries.

Acknowledgments: The authors gratefully acknowledge the financial support received from the Ministry of Science and Technology of Taiwan under grant numbers MOST 109-3116-F-006-016-CC1, 109-2621-M-029-001 and 107-2221-E-006-112-MY3.

https://www.sciencedirect.com/science/article/abs/pii/S0144861720311796

Source: The abstract and data are based on the article: Liu Z., Song S., Shi Z., Zhang W., Zhang G., Ying Y., & Liu D. (2021). Advanced extraction techniques of polysaccharides from natural materials: Progress, challenges and perspectives. Published in Carbohydrate Polymers, Vol. 251. Read the full article on ScienceDirect.

References (124)

• I. Aguiló-Aguayo et al. Ultrasound assisted extraction of polysaccharides from mushroom by-products. LWT (2017)
• I. Alzorqi et al. Ultrasonically extracted β-d-glucan from artificially cultivated mushroom, characteristic properties and antioxidant activity. Ultrasonics Sonochemistry (2017)
• Ó. Benito-Román et al. β-Glucan recovery from Ganoderma lucidum by means of pressurized hot water and supercritical CO2. Food and Bioproducts Processing (2016)
• D.U. Bhotmange et al. Enzymatic extraction and characterization of polysaccharide from Tuber aestivum. Bioactive Carbohydrates and Dietary Fibre (2017)
• B. Chen. Optimization of extraction of Tremella fuciformis polysaccharides and its antioxidant and antitumour activities in vitro. Carbohydrate Polymers (2010)
• C. Chen et al. Optimization of dynamic microwave-assisted extraction of Armillaria polysaccharides using RSM, and their biological activity. LWT – Food Science and Technology (2015)
• T.-Q. Chen et al. Efficient extraction technology of antioxidant crude polysaccharides from Ganoderma lucidum (Lingzhi), ultrasonic-circulating extraction integrating with superfine-pulverization. Journal of the Taiwan Institute of Chemical Engineers (2014)
• W. Chen et al. Optimization of ultrasonic-assisted extraction of water-soluble polysaccharides from Boletus edulis mycelia using response surface methodology. Carbohydrate Polymers (2012)
• X. Chen et al. Optimization of ultrasound-assisted extraction of Lingzhi polysaccharides using response surface methodology and its inhibitory effect on cervical cancer cells. Carbohydrate Polymers (2010)
• Y. Chen et al. Optimization of ultrasonic/microwave assisted extraction (UMAE) of polysaccharides from Inonotus obliquus and evaluation of its anti-tumor activities. International Journal of Biological Macromolecules (2010)
• L.I. de Jesus et al. Simple and effective purification approach to dissociate mixed water-insoluble α- and β-D-glucans and its application on the medicinal mushroom Fomitopsis betulina. Carbohydrate Polymers (2018)
• Y. Fan et al. Physical characteristics and antioxidant effect of polysaccharides extracted by boiling water and enzymolysis from Grifola frondosa. International Journal of Biological Macromolecules (2011)
• A. Gil-Ramírez et al. Strengths and weaknesses of the aniline-blue method used to test mushroom (1→3)-β-d-glucans obtained by microwave-assisted extractions. Carbohydrate Polymers (2019)
• X. Guo et al. Optimization of extraction process by response surface methodology and preliminary characterization of polysaccharides from Phellinus igniarius. Carbohydrate Polymers (2010)
• H. Hou et al. pH recycling aqueous two-phase systems applied in extraction of Maitake β-Glucan and mechanism analysis using low-field nuclear magnetic resonance. Journal of Chromatography A (2015)
• S.-q. Huang et al. Extraction of polysaccharide from Ganoderma lucidum and its immune enhancement activity. International Journal of Biological Macromolecules (2010)
• A.Y. Hwang et al. Effects of non-traditional extraction methods on extracting bioactive compounds from chaga mushroom (Inonotus obliquus) compared with hot water extraction. LWT (2019)
• S. Jia et al. Effects of extraction methods on the antioxidant activities of polysaccharides from Agaricus blazei Murrill. International Journal of Biological Macromolecules (2013)
• F. Jiao et al. Processing optimization and anti-oxidative activity of enzymatic extractable polysaccharides from Pleurotus djamor. International Journal of Biological Macromolecules (2017)
• A. Klaus et al. Antioxidative activities and chemical characterization of polysaccharides extracted from the basidiomycete Schizophyllum commune. LWT – Food Science and Technology (2011)
• H. Li. Extraction, purification, characterization and antioxidant activities of polysaccharides from Ramaria botrytis (Pers.) Ricken. Chemistry Central Journal (2017)
• W. Li et al. Physicochemical properties of polysaccharides from Lentinus edodes under high pressure cooking treatment and its enhanced anticancer effects. International Journal of Biological Macromolecules (2018)
• X. Li et al. Effect of extraction method on structure and antioxidant activity of Hohenbuehelia serotina polysaccharides. International Journal of Biological Macromolecules (2016)
• X. Li et al. Ultrasonic-assisted extraction of polysaccharides from Hohenbuehelia serotina by response surface methodology. International Journal of Biological Macromolecules (2012)
• Y. Lin et al. Microwave-assisted aqueous two-phase extraction of diverse polysaccharides from Lentinus edodes: Process optimization, structure characterization and antioxidant activity. International Journal of Biological Macromolecules (2019)
• Y. Liu et al. Extraction optimization, characterization, antioxidant and immunomodulatory activities of a novel polysaccharide from the wild mushroom Paxillus involutus. International Journal of Biological Macromolecules (2018)
• T.C.-T. Lo et al. Correlation evaluation of antioxidant properties on the monosaccharide components and glycosyl linkages of polysaccharide with different measuring methods. Carbohydrate Polymers (2011)
• G. Mao et al. Extraction, preliminary characterization and antioxidant activity of Se-enriched Maitake polysaccharide. Carbohydrate Polymers (2014)
• M. Marić et al. An overview of the traditional and innovative approaches for pectin extraction from plant food wastes and by-products: Ultrasound-, microwaves-, and enzyme-assisted extraction. Trends in Food Science & Technology (2018)
• Y.-Z. Miao et al. Extraction of water-soluble polysaccharides (WSPS) from Chinese truffle and its application in frozen yogurt. Carbohydrate Polymers (2011)
• D. Morales et al. Testing the effect of combining innovative extraction technologies on the biological activities of obtained β-glucan-enriched fractions from Lentinula edodes. Journal of Functional Foods (2019)
• I. Palacios et al. Novel isolation of water-soluble polysaccharides from the fruiting bodies of Pleurotus ostreatus mushrooms. Carbohydrate Research (2012)
• Y. Pan et al. Ultrasonic-assisted extraction process of crude polysaccharides from Yunzhi mushroom and its effect on hydroxyproline and glycosaminoglycan levels. Carbohydrate Polymers (2010)
• Y. Pan et al. Ultrasonic-assisted extraction, chemical characterization of polysaccharides from Yunzhi mushroom and its effect on osteoblast cells. Carbohydrate Polymers (2010)
• J.-J. Pei et al. Structural features and antitumor activity of a novel polysaccharide from alkaline extract of Phellinus linteus mycelia. Carbohydrate Polymers (2015)
• M. Puri et al. Enzyme-assisted extraction of bioactives from plants. Trends Biotechnol (2012)
• P. Rodríguez-Seoane et al. Innovative technologies for the extraction of saccharidic and phenolic fractions from Pleurotus eryngii. LWT (2019)
• A.C. Ruthes et al. d-Glucans from edible mushrooms: A review on the extraction, purification and chemical characterization approaches. Carbohydrate Polymers (2015)
• M. Shi et al. Effect of ultrasonic extraction conditions on antioxidative and immunomodulatory activities of a Ganoderma lucidum polysaccharide originated from fermented soybean curd residue. Food Chemistry (2014)
• X. Shu et al. Extraction, purification and properties of water-soluble polysaccharides from mushroom Lepista nuda. International Journal of Biological Macromolecules (2019)
• F.R. Smiderle et al. Evaluation of microwave-assisted and pressurized liquid extractions to obtain β-d-glucans from mushrooms. Carbohydrate Polymers (2017)
• C.-H. Su et al. Effects of different extraction temperatures on the physicochemical properties of bioactive polysaccharides from Grifola frondosa. Food Chemistry (2017)
• Y.-X. Sun et al. Purification, composition analysis and antioxidant activity of different polysaccharide conjugates (APPs) from the fruiting bodies of Auricularia polytricha. Carbohydrate Polymers (2010)
• Y. Sun et al. Technology optimization for polysaccharides (POP) extraction from the fruiting bodies of Pleurotus ostreatus by Box–Behnken statistical design. Carbohydrate Polymers (2010)
• A. Szwengiel et al. Deproteinization of water-soluble ß-glucan during acid extraction from fruiting bodies of Pleurotus ostreatus mushrooms. Carbohydrate Polymers (2016)
• Y. Tian et al. Ultrasonic-assisted extraction and antioxidant activity of polysaccharides recovered from white button mushroom (Agaricus bisporus). Carbohydrate Polymers (2012)
• N. Wang et al. Antioxidant property of water-soluble polysaccharides from Poria cocos Wolf using different extraction methods. International Journal of Biological Macromolecules (2016)
• Y. Wang et al. Extraction, preliminary characterization and in vitro antioxidant activity of polysaccharides from Oudemansiella radicata mushroom. International Journal of Biological Macromolecules (2018)
• Y. Wang et al. Optimization of polysaccharides extraction from Trametes robiniophila and its antioxidant activities. Carbohydrate Polymers (2014)
• Z.-B. Wang et al. Effect of extraction media on preliminary characterizations and antioxidant activities of Phellinus linteus polysaccharides. Carbohydrate Polymers (2014)
• There are more references available in the full text version of this article.

Cited by (199)

• Ultrasonic disruption effects on the extraction efficiency, characterization, and bioactivities of polysaccharides from Panax notoginseng flower. 2022, Carbohydrate Polymers
• Modulatory effects of polysaccharides from plants, marine algae and edible mushrooms on gut microbiota and related health benefits: A review. 2022, International Journal of Biological Macromolecules
• Healthy function and high valued utilization of edible fungi. 2021, Food Science and Human Wellness
• Polysaccharides-based bio-nanostructures and their potential food applications. 2021, International Journal of Biological Macromolecules
• Ultrasound modified polysaccharides: A review of structure, physicochemical properties, biological activities and food applications. 2021, Trends in Food Science and Technology
• Edible mushrooms: A comprehensive review on bioactive compounds with health benefits and processing aspects. 2021, Foods

Want to Go Deeper into Extraction Science?

This review is part of our commitment to transparency about how quality extracts are made. To learn more, explore our medicinal mushrooms overview and our glossary of terms, read about the triple-extraction method, and verify quality through our transparency page and lab testing (COA). Have a question? Visit our FAQ.

For practitioners: if you would like standards, active-compound details and evidence-based practice considerations, see our information for practitioners.

Dietary supplement. The above is an educational review based on preliminary research and traditional uses, and does not constitute medical advice or a therapeutic indication. These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. Do not begin use — especially while taking medications, during pregnancy or breastfeeding, or with an existing medical condition — without consulting a physician or qualified practitioner.