Hydrogel containing (1 → 6)-β-D-glucan (lasiodiplodan) effectively promotes dermal wound healing

Breaking the virus: Yeast glucans as an effective alternative to acyclovir in HSVI treatment

Glucans, structural polysaccharides in the yeast cell wall, are known for their biological and immunomodulatory capacities, helping in prevention and management of infections. Herpes simplex virus type 1 (HSVI) is a prevalent infection that causes great comorbidity and is challenging to treat due to the adverse effects of standard antiviral drugs like acyclovir. This study assessed the potential of yeast glucans extracted from two different origins - a steviol-glycoside producing strain and a wild-type strain- to circumvent HSVI infection, either in vitro and ex vivo. Treatment with glucans in keratinocytes and macrophages in vitro reduced cell infection similarly to acyclovir. However, unlike acyclovir, glucans demonstrated an immunostimulatory effect, increasing the production of IL-1β, TNF-α and IL-6. Additionally, both glucans were formulated with squalane for skin application. This formulation improved glucans penetration in the skin, restored skin structure and reduced the cytopathic effect of HSVI infection. In summary, this study highlights yeast glucans as a natural therapeutic alternative for HSVI treatment, offering an option with an excellent safety profile. Moreover, using glucans from industrial side-streams promotes a sustainable approach, contributing to the circular economy.

Microbial exopolysaccharides: Classification, biosynthetic pathway, industrial extraction and commercial production to unveil its bioprospection: A comprehensive review

Polysaccharides, found universally in all living-species, exhibit diverse biochemical structures and play crucial roles in microorganisms, animals, and plants to defend against pathogens, environmental stress and climate-changing. Microbial exopolysaccharides are essential for cell adhesion and stress resilience and using them has notable advantages over synthetic polysaccharides. Exopolysaccharides have versatile structures and physicochemical properties, used in food systems, therapeutics, cosmetics, agriculture, and polymer industries. Immense economic and infrastructural constraints hinder its widespread commercial use, necessitating a deeper understanding of metabolic-pathways amidst changing environmental climate that influences the biomass composition of EPS-producing wild-microbes. Green and sustainable extraction of EPS from microbes followed by commercial product development has still not been exploited comprehensively. Yield of EPS production vary from 0.1 to 3 g/g of cell weight, influenced by fermentation conditions. Economic barriers, including substrate and processing costs, limit commercial viability. Key biosynthetic pathways involve glycosyltransferases enzymes, whose regulatory network gaps and substrate specificity remain areas for optimization. Addressing these could enhance yields and lower production costs. Review illustrates various microbial-exopolysaccharides, influencing factors of production, and offer valuable insights on the bioplastic, biofuel, agri-bioproduct, and biomedicine. But their bioprospecting potential is yet to be exhaustively explored, along with their pros and cons nor documented comprehensively in scientific literature.

Antioxidant Potential and Chemical Evaluation of Extracts from Endophytic Fungus Lasiodiplodia sp

Antioxidants are compounds that can eliminate free radicals and are known to prevent cell damage and health disorders, in turn, improving the quality of life of human beings. This study aims to evaluate the presence of antioxidants in ethyl acetate (EtOAc) extracts from Lasiodiplodia endophyte, which was previously isolated and cultivated by our research group, given its ability to produce a variety of metabolites with different chemical and biological properties. The antioxidant activities were determined using ABTS+⋅, DPPH and FRAP. Total phenolic content (TPC) and total flavonoid content (TFC) were evaluated, as well as the NMR metabolomics of extracts. All extracts showed promising antioxidant activity, and optimal results were achieved between the sixth and eleventh days of fungus cultivation. Furthermore, one of the extracts showed no in vivo toxicity against Galleria mellonella for all tested concentrations. The 1H-NMR spectra showed that there are two distinct groups of molecules present in EtOAc extracts obtained from Lasiodiplodia cultivation, and the data corroborate the results concerning antioxidant activity for TPC and TFC. This suggests that it is possible to monitor the chemical profile of fungal extracts using NMR, and to correlate compounds within days of fungus cultivation, along with their antioxidant activities.

Polysaccharides and Peptides With Wound Healing Activity From Bacteria and Fungi

Bacteria and fungi are natural sources of metabolites exhibiting diverse bioactive properties such as wound healing, antioxidative, antibacterial, antifungal, anti-inflammatory, antidiabetic, and anticancer activities. Two important groups of bacteria or fungi-derived metabolites with wound-healing potential are polysaccharides and peptides. In addition to bacteria-derived cellulose and hyaluronic acid and fungi-derived chitin and chitosan, these organisms also produce different polysaccharides (e.g., exopolysaccharides) with wound-healing potential. The most commonly used bacterial peptides in wound healing studies are bacteriocins and lipopeptides. Bacteria or fungi-derived polysaccharides and peptides exhibit both the in vitro and the in vivo wound healing potency. In the in vivo models, including animals and humans, these metabolites positively affect wound healing by inhibiting pathogens, exhibiting antioxidant activity, modulating inflammatory response, moisturizing the wound environment, promoting the proliferation and migration of fibroblasts and keratinocytes, increasing collagen synthesis, re-epithelialization, and angiogenesis. Therefore, peptides and polysaccharides derived from bacteria and fungi have medicinal importance. This study aims to overview current literature knowledge (especially within the past 5 years) on the in vitro and in vivo wound repair potentials of polysaccharides and peptides obtained from bacteria (Actinobacteria, Bacteroidetes, Cyanobacteria, Firmicutes, and Proteobacteria) and fungi (yeasts, filamentous microfungi, and mushrooms).

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.

β-Glucans obtained from fungus for wound healing: A review

The cell surface of fungus contains a large number of β-glucans, which exhibit various biological activities such as immunomodulatory, anti-inflammatory, and antioxidation. Fungal β-glucans with highly branched structure show great potential as wound healing reagents, because they can stimulate the expression of many immune- and inflammatory-related factors beneficial to wound healing. Recently, the wound healing ability of many fungal β-glucans have been investigated in animals and clinical trials. Studies have proved that fungal β-glucans can promote fibroblasts proliferation, collagen deposition, angiogenesis, and macrophage infiltration during the wound healing process. However, the development of fungal β-glucans as wound healing reagents is not systematically reviewed till now. This review discusses the wound healing studies of β-glucans obtained from different fungal species. The structure characteristics, extraction methods, and biological functions of fungal β-glucans with wound healing ability are summarized. Researches about fungal β-glucan-containing biomaterials and structurally modified β-glucans for wound healing are also involved.

β-Glucan extracts as high-value multifunctional ingredients for skin health: A review

β-Glucans, which are naturally present in cereals, yeast, and mushrooms, have gained attention as a potential natural source for functional foods and pharmaceuticals. Due to the availability of β-glucans from several sources, different extraction methods can be employed to obtain high purity extracts that can be further modified to enhance their solubility or other biological properties. Apart from their known ability to interact with the immune system, β-glucans possess specific properties that could benefit overall skin health and prevent age-related signs, including soothing and antioxidant activities. As a result, the use of β-glucans to mitigate damage caused by environmental stressors or skin-related issues that accelerate skin aging or trigger chronic inflammation may represent a promising, natural, eco-friendly, and cost-effective approach to maintaining skin homeostasis balance. This review outlines β-glucan extraction methodologies, molecular structure, functionalization approaches, and explores skin-related benefits of β-glucans, along with an overview of related products in the market.

An additive-free multifunctional β-glucan-peptide hydrogel participates in the whole process of bacterial-infected wound healing

Bacterial infections and excessive inflammation can impede the healing of wounds. Hydrogels have emerged as a promising approach for dressing bacterial-infected injuries. However, some antibacterial hydrogels are complex, costly, and even require assistance with other instruments such as light, making them unsuitable for routine outdoor injuries. Here, we developed an in-situ generating hydrogel via hybridizing oxidized β-D-glucan with antimicrobial peptide C8G2 through the Schiff base reaction. This hydrogel is easily accessible and actively contributes to the whole healing process of bacterial-infected wounds, demonstrating remarkable antibacterial activity and biological compatibility. The pH-sensitive reversible imine bond enables the hydrogel to self-heal and sustainably release the antibacterial peptide, thereby improving its bioavailability and reducing toxicity. Meanwhile, the immunoregulating β-D-glucan inhibits the release of inflammatory factors while promoting the release of anti-inflammatory factors. In methicillin-resistant Staphylococcus aureus (MRSA)-infected full-thickness skin wound models, the hybrid hydrogel showed superior antibacterial and anti-inflammatory activity, enhanced the M2 macrophage polarization, expedited wound closure, and regenerated epidermis tissue. These features make this hydrogel an appealing wound dressing for treating multi-drug-resistant bacteria-infected wounds.

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.

Genome Sequencing and Analysis Reveal Potential High-Valued Metabolites Synthesized by Lasiodiplodia iranensis DWH-2

Lasiodiplodia sp. is a typical opportunistic plant pathogen, which can also be classified as an endophytic fungus. In this study, the genome of a jasmonic-acid-producing Lasiodiplodia iranensis DWH-2 was sequenced and analyzed to understand its application value. The results showed that the L. iranensis DWH-2 genome was 43.01 Mb in size with a GC content of 54.82%. A total of 11,224 coding genes were predicted, among which 4776 genes were annotated based on Gene Ontology. Furthermore, the core genes involved in the pathogenicity of the genus Lasiodiplodia were determined for the first time based on pathogen-host interactions. Eight Carbohydrate-Active enzymes (CAZymes) genes related to 1,3-β-glucan synthesis were annotated based on the CAZy database and three relatively complete known biosynthetic gene clusters were identified based on the Antibiotics and Secondary Metabolites Analysis Shell database, which were associated with the synthesis of 1,3,6,8-tetrahydroxynaphthalene, dimethylcoprogen, and (R)-melanin. Moreover, eight genes associated with jasmonic acid synthesis were detected in pathways related to lipid metabolism. These findings fill the gap in the genomic data of high jasmonate-producing strains.

The impact of Allgower-Donati suture pattern and postoperative sweet foods on wound suture breakage in experimental rats

Background

Wound gnawing and/or scratching in rats often occurs in experimental models, causing suture breakage and wound dehiscence, and consequently affecting experimental results and wasting resources. This study aimed to investigate the impact of the combined postoperative use of the Allgower-Donati (A-D) suture pattern and sweet foods on suture breakage, inflammation, and healing in wounds.

Materials and methods

Sprague Dawley (SD) rats (n = 48) were treated for linear wounds on the back by four procedures: simple suture, simple suture with postoperative sweet foods, A-D suture, and A-D suture with postoperative sweet foods. Additionally, CD68 immunofluorescence and CD31 immunohistochemistry were used to analyze wound inflammation and vascularization, respectively, on postoperative day 7. Sirius red staining was used to assess collagen deposition on postoperative day 14.

Results

Gnawing and scratching of wound sutures were significantly reduced in treated rats (P < 0.01). Neovascularization and collagen deposition were significantly increased (P < 0.001), and inflammatory responses were significantly reduced (P < 0.001) in animals receiving AD sutures and postoperative sweet foods. CD31/CD68 analyses showed that A-D suture and postoperative sweet foods regulated wound angiogenesis and attenuated wound inflammation.

Conclusions

Sweet food provision after A-D suture union surgery could reduce wound gnawing and/or scratching, suture breakage, incisional dehiscence, wound inflammation, and promote wound healing in rats.

Aldehyde-mediated adaptive membranes with self-healing and antimicrobial properties for endometrial repair

Traditional treatment methods for irreversible endometrial damage face a number of challenges in clinical practice, the most important of which are bacterial infection and the inability to restore endometrial function. By modifying glucan, oxidized dextran (OD) with multifunctional aldehyde groups was obtained in this study. Based on the dynamic Schiff base reaction between gelatin (GA) and OD, a GA-OD adaptive membrane with good biocompatibility, self-healing, biodegradability, and antimicrobial properties was created. In vitro studies revealed that GA and OD cross-linking overcame GA's low gel temperature, accelerated gelling, and improved mechanical properties, hydrophilicity, and degradability. The dynamic bond formed by the reaction between GA and OD caused the GA-OD film to self-heal. Meanwhile, the GA-OD membrane had antibacterial properties. To assess the repair effect of GA-OD film, an in vivo rat endometrial injury model filled with GA-OD adaptive membrane was created. According to the results of the study, the GA-OD membrane was biocompatible, and the uterine tissue did not have edema and inflammation. Further study on the postoperative endometrial regeneration effect of GA-OD material showed that it had an excellent ability for epithelial reconstruction and cell proliferation. As a result, the use of GA-OD composite film in endometrial repair has promising therapeutic implications.

Exopolysaccharides of Fungal Origin: Properties and Pharmaceutical Applications

Fungal exopolysaccharides (EPSs) represent an important group of bioactive compounds secreted by fungi. These biopolymers can be utilized individually or in combination with different bioactive substances for a broad range of pharmaceutical field applications, due to their various biological activities, such as antioxidant, antimicrobial, anti-inflammatory, antiviral, anti-diabetic, and anticoagulant effects. The paper presents an up-to-date review of the main fungal polysaccharides (pullulan, schizophyllan, scleroglucan, botryosphaeran, lentinan, grifolan, and lasiodiplodan), highlighting their structures, producing strains, and useful properties in a double position, as controlled release (rate and selectively targeting) drug carriers, but mostly as active immunomodulating and antitumor compounds in cancer therapy.

Evaluation of two fungal exopolysaccharides as potential biomaterials for wound healing applications

Microbial exopolysaccharides (EPSs) are mostly produced by bacteria and fungi and have potential use in the production of biomedical products such as nutraceuticals and in tissue engineering applications. The present study investigated the in vitro biological activities and in vivo wound healing effects of EPSs produced from a Sclerotium-forming fungus (Sclerotium glucanicum DSM 2159) and a yeast (Rhodosporidium babjevae), denoted as scleroglucan (Scl) and EPS-R, respectively. EPS yields of 0.9 ± 0.07 g/L and 1.11 ± 0.4 g/L were obtained from S. glucanicum and R. babjevae, respectively. The physicochemical properties of the EPSs were characterized using infrared spectroscopy and scanning electron microscopy. Further investigations of the biological properties showed that both EPSs were cytocompatible toward the human fibroblast cell line and demonstrated  hemocompatibility. Favorable wound healing capacities of the EPSs (10 mg/mL) were also established via in vivo tests. The present study therefore showed that the EPSs produced by S. glucanicum and R. babjevae have the potential use as biocompatible components for the promotion of dermal wound healing.

Valorization of pineapple processing residues through acetification to produce specialty vinegars enriched with red-Jambo extract of Syzygium malaccense leaf

The present study proposes the production of vinegars from pineapple processing residues as an eco-friendly strategy for adding value and economic strengthening of the production chain. Pineapple pulp and peel wines were produced and acetificated to vinegar by wild strains of acetic bacteria using Orlean's method (traditional system) followed by enrichment with leaf extract of Red-Jambo, Syzygium malaccense. Appreciable phenolic contents and antioxidant potential were found in pulp and peel vinegars with the added leaf extract. Catechin, epicatechin and caffeic, p-coumaric, ferulic, and gallic acids were the main phenolic compounds found in peel vinegar. The enrichment of the vinegar with the extract promoted an increase in the content of polyphenols (443.6-337.3 mg GAE/L) and antioxidant activity. Peel wines presented higher luminosity (L^*) and higher saturation index (C^*), and their color tended more toward yellow than pulp wines. Acetification reduced the saturation index (C^*) and led to the intensification of the hue angle in the peels vinegar. Each type of pineapple vinegar produced showed biocidal activity against different bacteria and yeast, and the addition of leaf extract potentiated the antimicrobial activity of peel vinegar, especially against Staphalococcus aureus. The vinegars developed could find an attractive market niche in the food sector.

An important polysaccharide from fermentum

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Extraction, structure and modification of polysaccharides from fermentum were summarized.

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Structure-activity relationship and application of polysaccharides from fermentum were reviewed.

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It provided a strong basis for the development and application of polysaccharides from fermentum.

Fermentum is a common unicellular fungus with many biological activities attributed to β-polysaccharides. Different in vivo and in vivo experimental studies have long proven that fermentum β-polysaccharides have antioxidant, anti-tumor, and fungal toxin adsorption properties. However, there are many uncertainties regarding the relationship between the structure and biological activity of fermentum β-polysaccharides, and a systematic summary of fermentum β-polysaccharides is still lacking. Herein, we reviewed the research progress about the extraction, structure and modification, structure–activity relationship, activity and application of fermentum β-polysaccharides, compared the extraction methods of fermentum β-polysaccharide, and paid special attention to the structure–activity relationship and application of fermentum β-polysaccharide, which provided a strong basis for the development and application of fermentum β-polysaccharide.

Sulfonated (1 → 6)-β-d-Glucan (Lasiodiplodan): A Promising Candidate against the Acyclovir-Resistant Herpes Simplex Virus Type 1 (HSV-1) Strain

Herpes simplex virus type 1 (HSV-1) is a persistent human pathogen, and the emergence of strains resistant to Acyclovir (ACV, reference drug) shows the urgency to develop new treatments. We report the antiherpetic mechanism of the action of lasiodiplodan (LAS-N, (1 → 6)-β-d-glucan) and its sulfonated derivative (LAS-S3) in vitro and in vivo. LAS-S3 showed anti-HSV-1 action with high selectivity indices for HSV-1 KOS (88.1) and AR (189.2), sensitive and resistant to ACV, respectively. LAS-S3 inhibited >80% of HSV-1 infection in different treatment protocols (virucidal, adsorption inhibition, and post-adsorption effects), even at low doses, and showed a preventive effect and DNA and protein synthesis inhibition. The antiherpetic effect was confirmed in vivo by the cosmetic LAS-S3-CRÈME decreasing cutaneous lesions of HSV-1, including the AR strain. LAS-S3 possessed a broad-spectrum mechanism of action acting in the early and post-adsorption stages of HSV-1 infection, and LAS-S3-CRÈME is a potential antiherpetic candidate for patients infected by HSV-1-resistant strains.

Ultrasound-assisted enzymatic hydrolysis of yeast β-glucan catalyzed by β-glucanase: Chemical and microstructural analysis

The purpose of this study was to investigate the effect of ultrasound-assisted enzymolysis on modified solubilization of yeast β-glucan and its related mechanism. The depolymerization effects of this system on the physicochemical properties and structural features of the degraded fragments were studied systematically. The structure and physicochemical properties of the samples showed that the solubility of yeast β-glucan achieved 75.35 % after modification; and ultrasonic enzymatic enhanced the degradation efficiency. The yeast β-glucan obtained after solubilization and modification owned better antioxidant activities. The yeast β-glucan particles become obviously smaller, sparsely dispersed in the aqueous solution and the stability was improved. In addition, the hydrogen bonds in yeast β-glucan native triple helix structure were partially broken. Moreover, the disruption of yeast β-glucan's original structure made it decreased thermostability and easier to dissolve in water. The atomic force microscope (AFM) imaging directly verified the branched-chain morphology of yeast β-glucan and the small-strand degradation fragments. Therefore, this research can provide a feasible and effective approach for improving solubility of water-insoluble yeast β-glucan to enlarge its food and biomedical applications.

Encapsulation and dispersion of Lactobacillus acidophilus in a chocolate coating as a strategy for maintaining cell viability in cereal bars

Flour from Pereskia aculeata leaf and green banana were used as ingredients in the formulation of a cereal bar with added Lactobacillus acidophilus LA02-ID-1688. Encapsulation in a calcium-alginate hydrogel reinforced with magnesium hydroxide was used as a strategy to protect the probiotic cells under gastrointestinal conditions and to prolong shelf-life. The results are relevant especially for maintaining cell viability during shelf-life; a challenge for the food industry in relation to dry probiotic products. Encapsulation promoted the protection of probiotic cells in simulated gastric and intestinal conditions, allowing the maintenance of high viable cell counts (> 10 log CFU, colony forming unit). Encapsulation also contributed to cellular protection under extreme temperature conditions, with reductions of cell viability of < 1 logarithmic cycle when the capsules were subjected to 55ºC/10 min. Even at 75ºC/10 min, encapsulation protected the probiotic cells 3-times greater than the free-cells. The food bar proved to be rich in dietary fiber (19 g 100 g-1), lipids (12.63 g 100 g-1) and showed an appreciable protein content (5.44 g 100 g-1). A high viable probiotic cell count on storage over 120 days (12.54 log CFU) was observed, maintaining a probiotic survival rate > 90% and viability levels sufficient to promote health benefits.