Low-Molecular-Weight β-1,3-1,6-Glucan Derived from Aureobasidium pullulans Exhibits Anticancer Activity by Inducing Apoptosis in Colorectal Cancer Cells

β-glucan: a potent adjuvant in immunotherapy for digestive tract tumors

The immunotherapy for gastrointestinal tumors, as a significant research direction in the field of oncology treatment in recent years, has garnered extensive attention due to its potential therapeutic efficacy and promising clinical application prospects. Recent advances in immunotherapy notwithstanding, challenges persist, such as side effects, the complexity of the tumor immune microenvironment, variable patient responses, and drug resistance. Consequently, there is a pressing need to explore novel adjunctive therapeutic modalities. β-glucan, an immunomodulatory agent, has exhibited promising anti-tumor efficacy in preclinical studies involving colorectal cancer, pancreatic cancer, and gastric cancer, while also mitigating the adverse reactions associated with chemotherapy and enhancing patients' quality of life. However, further clinical and fundamental research is warranted to comprehensively evaluate its therapeutic potential and underlying biological mechanisms. In the future, β-glucan holds promise as an adjunctive treatment for gastrointestinal tumors, potentially bringing significant benefits to patients.

Recent advances in the biosynthesis of fungal glucan structural diversity

Glucans are the most abundant class of macromolecule polymers in fungi, which are commonly found in Ascomycota and Basidiomycota. Fungal glucans are not only essential for cell integrity and function but also crucial for the immense industrial interest in high value applications. They present a variety of structural characteristics at the nanoscale due to the high regulation of genes and the involvement of stochastic processes in synthesis. However, although recent findings have demonstrated the genes of glucans synthesis are relatively conserved across diverse fungi, the formation and organization of diverse glucan structures is still unclear in fungi. Here, we summarize the structural features of fungal glucans and the recent developments in the mechanisms of glucans biosynthesis. Furthermore, we propose the engineering strategies of targeted glucan synthesis and point out the remaining challenges in the synthetic process. Understanding the synthesis process of diverse glucans is necessary for tailoring high value glucan towards specific applications. This engineering strategy contributes to enable the sustainable and efficient production of glucan diversity.

Use of Aureobasidium in a sustainable economy

Aureobasidium is omnipresent and can be isolated from air, water bodies, soil, wood, and other plant materials, as well as inorganic materials such as rocks and marble. A total of 32 species of this fungal genus have been identified at the level of DNA, of which Aureobasidium pullulans is best known. Aureobasidium is of interest for a sustainable economy because it can be used to produce a wide variety of compounds, including enzymes, polysaccharides, and biosurfactants. Moreover, it can be used to promote plant growth and protect wood and crops. To this end, Aureobasidium cells adhere to wood or plants by producing extracellular polysaccharides, thereby forming a biofilm. This biofilm provides a sustainable alternative to petrol-based coatings and toxic chemicals. This and the fact that Aureobasidium biofilms have the potential of self-repair make them a potential engineered living material avant la lettre. KEY POINTS: •Aureobasidium produces products of interest to the industry •Aureobasidium can stimulate plant growth and protect crops •Biofinish of A. pullulans is a sustainable alternative to petrol-based coatings •Aureobasidium biofilms have the potential to function as engineered living materials.

Recent Advances in the Preparation, Structure, and Biological Activities of β-Glucan from Ganoderma Species: A Review

Ganoderma has served as a valuable food supplement and medicinal ingredient with outstanding active compounds that are essential for human protection against chronic diseases. Modern pharmacology studies have proven that Ganoderma β-d-glucan exhibits versatile biological activities, such as immunomodulatory, antitumor, antioxidant, and antiviral properties, as well as gut microbiota regulation. As a promising polysaccharide, β-d-glucan is widely used in the prevention and treatment of various diseases. In recent years, the extraction, purification, structural characterization, and pharmacological activities of polysaccharides from the fruiting bodies, mycelia, spores, and fermentation broth of Ganoderma species have received wide attention from scholars globally. Unfortunately, comprehensive studies on the preparation, structure and bioactivity, toxicology, and utilization of β-d-glucans from Ganoderma species still need to be further explored, which may result in limitations in future sustainable industrial applications of β-d-glucans. Thus, this review summarizes the research progress in recent years on the physicochemical properties, structural characteristics, and bioactivity mechanisms of Ganoderma β-d-glucan, as well as its toxicological assessment and applications. This review is intended to provide a theoretical basis and reference for the development and application of β-d-glucan in the fields of pharmaceuticals, functional foods, and cosmetics.