Konjac glucomannan, a promising polysaccharide of Amorphophallus konjac K. Koch in health care

Extraction, structure, activity and application of konjac glucomannan

Konjac is a perennial herbaceous plant from the Araceae family's Amorphophallus genus. It has high nutritional, health, and pharmacological values. It contains various bioactive components, the most notable of which is konjac glucomannan, which has several biological roles, including efficiently fighting diabetes, exerting prebiotic activity, containing antioxidant capacity, modulating immunological function, and demonstrating anti-cancer potential. Currently, the konjac glucomannan (KGM) research mainly focuses on packaging film, gel characteristics, efficacy, and evaluation. However, the extraction, underlying portrayal, derivatization, and action of KGM are seldom detailed. Herein, the utilization of konjac as an unrefined substance was surveyed, meaning to give extensive and orderly recombinant data on the extraction, decontamination, structure, natural movement, derivatization, and use of KGM to provide a full play to the interesting gelatinate, biocompatibility, high viscosity and other properties of KGM. It provided a theoretical basis for further developing the konjac glucomannan food industry, pharmaceutical field, and other fields.

Prebiotic Effects of Insoluble Konjac Glucomannan Derived from Edible "Konnyaku" on Weight Control

Obesity is a major global health issue, and novel dietary approaches are needed for prevention and management. This study investigates the effect of insoluble konjac glucomannan (iKGM) derived from edible konnyaku, a traditional Japanese food, on weight gain suppression in mice. Mice treated with iKGM showed increased fecal volume, reduced food intake, and suppressed weight gain (Day 21; p < 0.01). This weight-suppression effect was prebiotic rather than physical properties of iKGM, as antibiotic treatment abolished the weight-suppressing effect despite increased fecal volume. iKGM treatment altered the gut microbiota, notably increasing Akkermansia muciniphila (Day 21; p < 0.01), a bacterium associated with weight loss, along with elevated levels of short-chain fatty acids (SCFAs) such as butyrate and propionate (Day 21; p < 0.01). Furthermore, iKGM-induced weight suppression was linked to elevated leptin levels (Day 21; p < 0.01), an appetite suppressant induced by SCFAs. These results suggest that iKGM modulates gut microbiota, increases A. muciniphila, induces leptin production, and reduces food intake, inhibiting weight gain. This study indicates that iKGM may represent a promising approach for obesity prevention through gut microbiota modulation. Future research should investigate the mechanisms of iKGM's effects on microbiota and explore its long-term safety and efficacy in clinical trials.

Calcium alginate-cross-linked deacetylated konjac glucomannan-based double network hydrogels: Construction, characterizations and gelation kinetics

Deacetylated Konjac Glucomannan (DKGM) hydrogels frequently fail to meet commercial standards because of their weak gel strength and low mechanical characteristics. In this regard, we successfully constructed DKGM and calcium alginate (CA) double network hydrogels (DKGM/CA DNs) through the two-step sequential network formation technique for the first time. The microstructure, gel properties and gel kinetics of DKGM/CA DNs were investigated in multiple dimensions. Notably after the introduction of CA gel network into DKGM hydrogels, the system's gel network pores became dense, the water freedom decreased, and the gel strength, hardness, gumminess and other properties were 10-25 times higher than pure DKGM hydrogels. Further gel kinetics analysis showed that the presence of sodium alginate (SA) increased the gelation rate of DKGM during the gelation process, shorten the sol-to-gel time, and reduced the complex modulus of the gel system. In contrast, the presence of DKGM hydrogels would hinder the penetration and diffusion of Ca2+ solution, thus slowing down the crosslinking rate of SA and Ca2+. In summary, this study provides a new solution for improving the mechanical properties of DKGM hydrogels in a green and efficient manner.

Effects of deacetylated konjac glucomannan on the retrogradation properties of pea, mung bean and potato starches during the storage

The retrogradation of natural starches often leads to quality deterioration of starchy foods during storage and limits their applications, while hydrocolloids can effectively improve the quality of retrogradation starches. Therefore, the effects of deacetylated konjac glucomannan (DKGM) on the retrogradation properties of pea starch (PS), mung bean starch (MBS) and potato starch (ST) during storage were investigated. The rheological properties, water flowability, structural properties and microstructure of the samples were comparatively analyzed. The results showed that DKGM could effectively improve the viscoelasticity and pseudoplasticity of the starch gels. With the increase in the proportion of DKGM, the hardness and water retention of the composite system were improved, and the microstructure of starch gels was also enhanced. In addition, the hydrogen bonds formed between DKGM and starch molecules restricted the cross-linking of amylose and the formation of starch double-helix structure, which reduced the crystallinity of starch. In summary, DKGM enhanced the network structure of starch gels and inhibited starch retrogradation, which lays the foundation for the study of the role of DKGM in the shelf life and organoleptic qualities of starchy foods.

A Novel Method for Extracting Glucomannan Using an Aqueous Two-Phase System

Research background

Glucomannan is a polysaccharide compound used widely in food and pharmaceutical industries. The tuber of Amorphophallus muelleri Blume is called porang in Indonesia. Ethanol extraction is commonly used to extract glucomannan from porang flour; however, the method has some limitations. Glucomannan obtained by ethanol extraction has a higher protein content than standard glucomannan. In this work, the salting-out effect of the salts of the aqueous two-phase system was investigated for the extraction of glucomannan. In this way, the protein can be removed from the glucomannan flour, thus increasing the purity of the obtained glucomannan.

Experimental approach

A novel glucomannan extraction method using an aqueous two-phase system (ATPS) consisting of salt and ethanol was investigated. The Na2HPO4 and K2HPO4 salts at 3 different mass fractions (1, 2 and 3 %) mixed with 40 % ethanol in a 1:1 volume ratio were used to prepare the ATPS. The efficiency of ATPS in the extraction of glucomannan was based on the phase separation and better properties of glucomannan, including proximate composition, colour, thermal properties and surface morphology were obtained. Statistical analysis was performed to test the significant differences between the mean values of each treatment. The statistical significance level was set at p=0.05.

Results and conclusions

The results showed that the aqueous two-phase system was able to separate a solution of porang flour into three layers, namely bottom (F1), middle (F2) and top (F3) layer. The bottom (F1) and middle (F2) layers were rich in glucomannan and starch, respectively, while the top layer (F3) consisted of an ethanol-soluble compound. The salts affected the yield of glucomannan and the properties of the obtained glucomannan, including colour, impurities (protein and ash), thermal properties, molecular mass and surface morphology. Increasing salt mass fraction decreased the yield of glucomannan but increased the yield of other components. ATPS reduced the protein content and increased the lightness of the glucomannan. The glucomannan obtained with ATPS had a higher thermal stability than the control.

Novelty and scientific contribution

Salting-out ability of the salt of the aqueous two-phase system is commonly used in protein precipitation and isolation. However, there was no report found on the application of ATPS for the isolation of glucomannan. This study has shown that the ATPS (ethanol/Na2HPO4 and ethanol/K2HPO4) is a potential new extraction method for glucomannan extraction.

Genomic, transcriptomic and metabolomic analyses of Amorphophallus albus provides insights into the evolution and resistance to southern blight pathogen

Introduction

Amorphophallus albus, a perennial herb in the Araceae family, is a valuable cash crop known for its high production of konjac glucomannan and high disease resistance.

Methods

In this study, we present a high-quality, chromosome-scale genome assembly of A. albus using a combination of PacBio HiFi sequencing, DNBSEQ short-read sequencing, and Hi-C technology. To elucidate the molecular mechanisms underlying southern blight resistance, we performed an integrated analysis of transcriptomic and metabolomic profiles across three infection stages of A. albus.

Results and discussion

Here, we assembled and annotated the complete genome of A. albus, providing a chromosome-level assembly with a total genome size of 5.94 Gb and a contig N50 of 5.61 Mb. The A. albus genome comprised 19,908 gene families, including 467 unique families.The slightly larger genome size of A. albus compared to A. konjac may have been affected by a recent whole-genome duplication event. Transcriptional and metabolic analyses revealed significant enrichment of differentially expressed genes (DEGs) and differentially accumulated metabolites (DAMs) involved in phenylpropanoid biosynthesis, plant hormone signal transduction, phenylalanine metabolism, and the biosynthesis of phenylalanine, tyrosine, and tryptophan. These findings not only advance the understanding of genetic and evolutionary characteristics of A. albus but also provide a foundation for future research on the resistance mechanisms of konjac against southern blight disease.

Alcogels based on secalin and konjac glucomannan composites for the controlled release of curcumin

Alcogel has been increasingly applied in foods, cosmetics, and pharmaceutical industries. However, their application is limited by the lack of efficient biomacromolecule-based gelators. Herein, we present our discovery of secalin, a prolamin from rye, combined with konjac glucomannan (KGM) as novel food-grade gelators. Secalin-KGM (SK) alcogels could be prepared by directly cooling down their alcoholic solution, resulting in a thermo-induced sol-gel transition. SK gels (5 w/v % in 50 v/v % ethanol solution) exhibited diverse microstructural features and tunable mechanical properties that could be adjusted by varying the ratio of secalin to KGM. Microscopic images showed that when blended at a certain ratio, a homogeneous porous network is formed due to strong intermolecular interactions. Moreover, the SK gels exhibited a great ability to controllably release curcumin under simulated gastrointestinal tract conditions. The findings provide a novel plant protein-polysaccharide system to develop alcogels with tunable gelling properties and digestibility for functional food and drug delivery applications.

Physicochemical, structural properties, and in vitro digestibility of starches isolated from Amorphophallus konjac K. Koch and Amorphophallus dunnii: A comparison study

This study compared the physicochemical and structural properties, and in vitro digestibility of Amorphophallus konjac K. Koch starch (AKS) and Amorphophallus dunnii starch (ADS), by using potato starch (PS) as a control. ADS exhibited larger granule sizes, which led to higher transparency, swelling power (SP), and water solubility than AKS. Both AKS and ADS exhibited A-type crystalline patterns; however, ADS demonstrated higher relative crystallinity, gelatinization transition temperatures, and enthalpies of gelatinization, which may be due to higher 1047/1022 and more double helix contents. Regarding rheological and pasting properties, ADS exhibited greater viscosity than that of AKS, likely due to larger particle size and higher SP. In vitro digestion analysis revealed that >50 % of each starch type consisted of rapidly digestible starch. Notably, ADS contained the highest amount of resistant starch among the three types. The estimated glycemic index (eGI) values of AKS and ADS were 65.54 ± 0.54 and 63.28 ± 0.36, respectively, indicating that both starch types belong to the medium GI food category, though AKS was significantly higher than ADS. These findings suggest that konjac starch serves as a beneficial dietary carbohydrate alternative. AKS may be suited for fast-digesting food formulas for individuals with digestive impairment, whereas ADS could be advantageous for those managing diabetes.

Multifaceted roles of plant-derived bioactive polysaccharides: A review of their biological functions, delivery, bioavailability, and applications within the food and pharmaceutical sectors

Plant-derived bioactive polysaccharides (PDBPs), versatile polymers originating from various botanical sources, exhibit a spectrum of biological functionalities crucial for human health. This review delves into the multifaceted roles of these bioactive compounds, elucidating their immune-boosting properties, antioxidant prowess, anti-inflammatory capabilities, and contributions to gut health. Amidst their pivotal roles, the efficiency of PDBPs delivery and bioavailability in the human system stands as a central determinant of their efficacy and utilization. This review paper extensively and systematically examines the diverse biological activities, such as immunomodulatory effects, delivery mechanisms like microencapsulation, and promising applications of PDBPs within the realms of both food (functional foods and nutraceuticals) and pharmaceutical (antimicrobial agents and anti-inflammatory drugs) sectors. Additionally, it offers a comprehensive overview of the classification, sources, and structural diversity of these polysaccharides, highlighting various identification techniques and rheological considerations. Moreover, the review addresses critical safety and regulatory concerns alongside global legislation about plant bioactive polysaccharides, envisaging a broader landscape for their utilization. Through this synthesis, we aim to underscore the holistic significance of PDBPs and their potential to revolutionize nutritional and therapeutic paradigms.

Glucomannan engineering highlights roles of galactosyl modification in fine-tuning cellulose-glucomannan interaction in Arabidopsis cell walls

Widely found in most plant lineages, β-mannans are structurally diverse polysaccharides that can bind to cellulose fibrils to form the complex polysaccharide architecture of the cell wall. How changes in polysaccharide structure influence its cell wall solubility or promote appropriate interaction with cellulose fibrils is poorly understood. Glucomannan backbones acquire variable patterns of galactosyl substitutions, depending on plant developmental stage and species. Here, we show that fine-tuning of galactosyl modification on glucomannans is achieved by the differing acceptor recognition of mannan α-galactosyltransferases (MAGTs). Biochemical analysis and 13C solid-state　nuclear magnetic resonance spectroscopy of Arabidopsis with cell wall glucomannan engineered by MAGTs reveal that the degree of galactosylation strongly affects the interaction with cellulose. The findings indicate that plants tailor galactosyl modification on glucomannans for constructing an appropriate cell wall architecture, paving the way to convert properties of lignocellulosic biomass for better use.

Fabrication of Thymol-loaded Isabgol/Konjac Glucomannan-based Microporous Scaffolds with Enriched Antioxidant and Antibacterial Properties for Skin Tissue Engineering Applications

An antioxidant, antibacterial, and biocompatible biomaterial is essential to repair skin wounds effectively. Here, we have employed two natural biopolymers, isabgol (ISAB) and konjac glucomannan (KGM), to prepare microporous scaffolds by freezing and lyophilization. The scaffolds are loaded with thymol (THY) to impart potent antioxidant and antibacterial activities. The physicochemical properties of the ISAB+KGM+THY scaffold, like porosity (41.8±2.4 %), swelling, and biodegradation, were optimal for tissue regeneration application. Compared to the control, ISAB+KGM+THY scaffolds promote attachment, migration, and proliferation of L929 fibroblasts. The antioxidant activity of the ISAB+KGM+THY scaffold was significantly improved after loading THY. This would protect the tissues from oxidative damage. The antibacterial activity of the ISAB+KGM+THY scaffold was significantly higher than that of the control, which would help prevent bacterial infection. The vascularization ability of the ISAB+KGM scaffold was not altered by incorporating THY in the ISAB+KGM scaffold. Therefore, a strong antioxidant, antibacterial, and biocompatible nature of the ISAB+KGM+THY scaffold could be useful for various biomedical applications.

Therapeutic Efficacy and Underlying Mechanisms of a Mannoglucan from Hirsutella sinensis Mycelium on Dextran Sulfate Sodium-Induced Inflammatory Bowel Disease in Mice: Modulation of the Intestinal Barrier, Oxidative Stress and Gut Microbiota

Hirsutella sinensis (H. sinensis), a non-sexual form of the valuable Chinese medicinal herb, demonstrates various biological activities, such as immune modulation and antioxidative capabilities. Nonetheless, the effects of bioactive polysaccharides derived from H. sinensis on colitis have yet to be investigated. In our prior research, we extracted a mannoglucan (HSWP-1d) from H. sinensis and found that it attenuates TGF-β1-induced epithelial-mesenchymal transition. The present study investigated the protective effects of HSWP-1d against colitis induced by dextran sulfate sodium (DSS) in mice. The results demonstrate that HSWP-1d effectively ameliorates symptoms of colitis and preserves the intestinal barrier's stability by enhancing the expression of tight junction proteins. The administration of HSWP-1d results in a reduction in oxidative stress through the augmentation of antioxidative enzyme activities, concomitant with the suppression of oxidative product generation. Simultaneously, HSWP-1d reduced the levels of pro-inflammatory cytokines while elevating the levels of anti-inflammatory cytokines, effectively mitigating the inflammatory response. Furthermore, HSWP-1d influences and alters short-chain-fatty-acid (SCFA) levels, thereby enhancing the intestinal microenvironment. In conclusion, HSWP-1d contributes to intestinal well-being and holds potential as both a therapeutic choice and a supplier of essential nutrients for the amelioration of colitis.

Konjac glucomannan exerts regulatory effects on macrophages and its applications in biomedical engineering

Konjac glucomannan (KGM) molecular chains contain a small amount of acetyl groups and a large number of hydroxyl groups, thereby exhibiting exceptional water retention and gel-forming properties. To meet diverse requirements, KGM undergoes modification processes such as oxidation, acetylation, grafting, and cationization, which reduce its viscosity, enhance its mechanical strength, and improve its water solubility. Researchers have found that KGM and its derivatives can regulate the polarization of macrophages, inducing their transformation into classically activated M1-type macrophages or alternatively activated M2-type macrophages, and even facilitating the interconversion between M1 and M2 phenotypes. Concurrently, the modulation of macrophage polarization states holds significant importance for chronic wound healing, inflammatory bowel disease (IBD), antitumor therapy, tissue engineering scaffolds, oral vaccines, pulmonary delivery, and probiotics. Therefore, KGM has the advantages of both immunomodulatory effects (biological activity) and gel-forming properties (physicochemical properties), giving it significant advantages in a variety of biomedical engineering applications.

Konjac glucomannan-based composite materials: Construction, biomedical applications, and prospects

Konjac glucomannan (KGM) as an emerging natural polymer has attracted increasing interests owing to its film-forming properties, excellent gelation, non-toxic characteristics, strong adhesion, good biocompatibility, and easy biodegradability. Benefiting from these superior performances, KGM has been widely applied in the construction of multiple composite materials to further improve their intrinsic performances (e.g., mechanical strength and properties). Up to now, KGM-based composite materials have obtained widespread applications in diverse fields, especially in the field of biomedical. Therefore, a timely review of relevant research progresses is important for promoting the development of KGM-based composite materials. Innovatively, firstly, this review briefly introduced the structure properties and functions of KGMs based on the unique perspective of the biomedical field. Then, the latest advances on the preparation and properties of KGM-based composite materials (i.e., gels, microspheres, films, nanofibers, nanoparticles, etc.) were comprehensively summarized. Finally, the promising applications of KGM-based composite materials in the field of biomedical are comprehensively summarized and discussed, involving drug delivery, wound healing, tissue engineering, antibacterial, tumor treatment, etc. Impressively, the remaining challenges and opportunities in this promising field were put forward. This review can provide a reference for guiding and promoting the design and biomedical applications of KGM-based composites.

Impact of lecithin on the lubrication properties of konjac glucomannan gels

The effects of lecithin addition on the properties of konjac glucomannan (KGM) hydrogels prepared by controlled heating were investigated. Weak hydrogels were formed at 1 % KGM, which contained relatively thick strands. The shear viscosity and shear modulus of the hydrogels increased with increasing KGM concentration. The pure KGM hydrogels exhibited relatively poor boundary lubrication at all polysaccharide concentrations studied. The inclusion of lecithin (0.001 % to 0.20 %) in the KGM hydrogels appreciably altered their rheological properties, which could be modulated by varying the lecithin/KGM ratio. Microstructural analysis showed that lecithin caused a substantial restructuring of the strands in the hydrogel network. Lecithin was also found to be a highly effective lubricant in the KGM hydrogels. Incorporation of trace amounts of lecithin led to a significant improvement in the lubricating properties of the KGM hydrogels, especially boundary lubrication. Fourier transform infrared (FTIR) and differential canning calorimetry (DSC) analyses provided information about the molecular interactions between the lecithin and KGM molecules. The ability of lecithin to increase the lubricating performance of the KGM hydrogels was mainly attributed to the adsorption of phospholipid-biopolymer complexes onto solid surfaces, which reduced the friction between them.

In the process of polysaccharide gel formation: A review of the role of competitive relationship between water and alcohol molecules

Polysaccharides have emerged as versatile materials capable of forming gels through diverse induction methods, with alcohol-induced polysaccharide gels demonstrating significant potential across food, medicinal, and other domains. The existing research mainly focused on the phenomena and mechanisms of alcohol-induced gel formation in specific polysaccharides. Therefore, this review provides a comprehensive overview of the intricate mechanisms underpinning alcohol-triggered gelation of different polysaccharides and surveys their prominent application potentials through rheological, mechanical, and other characterizations. The mechanism underlying the enhancement of polysaccharide network structures by alcohol is elucidated, where alcohol displaces water to establish hydrogen bonding and hydrophobic interactions with polysaccharide chains. Specifically, alcohols change the arrangement of water molecules, and the partial hydration shell surrounding polysaccharide molecules is disrupted, exposing polysaccharides' hydrophobic groups and enhancing hydrophobic interactions. Moreover, the pivotal influences of alcohol concentration and addition method on polysaccharide gelation kinetics are scrutinized, revealing nuanced dependencies such as the different gel-promoting capabilities of polyols versus monohydric alcohols and the critical threshold concentrations dictating gel formation. Notably, immersion of polysaccharide gels in alcohol augments gel strength, while direct alcohol addition to polysaccharide solutions precipitates gel formation. Future investigations are urged to unravel the intricate nexus between the mechanisms underpinning alcohol-induced polysaccharide gelation and their practical utility, thereby paving the path for tailored manipulation of environmental conditions to engineer bespoke alcohol-induced polysaccharide gels.

A two-center randomized controlled trial of a repairing mask as an adjunctive treatment for mild to moderate rosacea

OBJECTIVE

To investigate the efficacy and safety of a repairing mask as an adjunctive treatment for skin barrier maintenance of mild to moderate rosacea.

METHODS

Patients with rosacea were recruited in this dual center randomized controlled trial from November 2019 to December 2021. A total of 64 patients were included and randomized into two groups at a ratio of 3:1 into a mask group (n = 47) and a control group (n = 17). Patients in the mask group received treatment with Dr. Yu Centella asiatica repairing facial mask three times weekly for a duration of 6 weeks. All participants were instructed to continue their regimen of 50 mg oral minocycline twice daily and to apply Dr. Yu Intensive Hydrating Soft Cream twice daily. The primary endpoint of this study was the Investigator Global Assessment (IGA) score.

RESULTS

A total of 54 patients completed this trial, with 41 in the mask group and 13 in the control group. After using this facial mask for 3 and 6 weeks, the IGA, facial skin dryness, facial flushing, and severity of skin lesion in the mask group showed significantly improvement (p < 0.05). Moreover, the change in the delta degree of skin flushing was significantly higher than that in the control group (p = 0.037). Throughout the study, no adverse events were reported in either group of participants.

CONCLUSION

The Dr. Yu Centella asiatica repairing facial mask, as an adjunctive treatment of rosacea, appears to effectively repair and protect the skin barrier, alleviate cutaneous symptoms of rosacea, and is both efficacious and safe for patient use.

pH-responsive IPN beads of carboxymethyl konjac glucomannan and sodium carboxymethyl cellulose as a controlled release carrier for ibuprofen

The convergence of polymer and pharmaceutical sciences has advanced drug delivery systems significantly. Carbohydrate polymers, especially carboxymethylated ones, offer versatile benefits for pharmaceuticals. Interpenetrating polymer networks (IPNs) combine synthetic and natural polymers to enhance drug delivery. The study aims to develop IPN beads using sodium carboxymethyl cellulose (SCMC) and carboxymethyl konjac glucomannan (CMKGM) for controlled release of ibuprofen (IB) after oral administration. Objectives include formulation optimization, characterization of physicochemical properties, evaluation of pH-dependent swelling and drug release behaviors to advance biocompatible and efficient oral drug delivery systems. The beads were analyzed using SEM, FTIR, DSC, and XRD techniques. Different ratio of polymers (CMKGM:SCMS) and crosslinker concentrations (2&4 %w/v) were used, significantly impacting bead size, swelling, drug encapsulation, and release characteristics. DSC results indicated higher thermal stability in IPN beads compared to native polymers. XRD revealed IB dispersion within the polymer matrix. IPN beads size ranged from 580 ± 0.56 to 324 ± 0.27 μm, with a nearly spherical shape. IPN beads exhibited continuous release in alkaline conditions (pH 7.4) and minimal release in acidic media (pH 1.2). These findings suggest that the formulated IPN beads can modulate drug release in both acidic and alkaline environments, potentially mitigating the gastric adverse effects often associated with oral administration of IB.

Konjac glucomannan: A comprehensive review of its extraction, health benefits, and pharmaceutical applications

Konjac glucomannan (KG) is a dietary fiber hydrocolloid derived from Amorphophallus konjac tubers and is widely utilized as a food additive and dietary supplement. As a health-conscious choice, purified KG, along with konjac flour and KG-infused diets, have gained widespread acceptance in Asian and European markets. An overview of the chemical composition and structure of KG is given in this review, along with thorough explanations of the processes used in its extraction, production, and purification. KG has been shown to promote health by reducing glucose, cholesterol, triglyceride levels, and blood pressure, thereby offering significant weight loss advantages. Furthermore, this review delves into the extensive health benefits and pharmaceutical applications of KG and its derivatives, emphasizing its prebiotic, anti-inflammatory, and antitumor activities. This study highlights how these natural polysaccharides can positively influence health, underscoring their potential in various biomedical applications.

Screening of Optimal Konjac Glucomannan-Protein Composite Gel Formulations to Mimic the Texture and Appearance of Tripe

This study aimed to develop a product that closely replicates the texture and appearance of tripe. The effect of three different proteins (soy protein isolate (SPI), pea protein isolate (PPI), and whey protein isolate (WPI)) at different protein levels and processing conditions (heating (90 °C, 1 h) followed by cooling (4 °C, 12 h) and heating (90 °C, 1h) followed by freezing (-18 °C, 12 h)) of konjac glucomannan (KGM) was analyzed. The optimal formulations for simulating tripe were screened by examining their similarity to real tripe in terms of texture, color, and sensory experience. The screened formulations were also subjected to a preliminary mechanistic investigation. The results show that all three proteins improved the gel's textural properties to varying degrees. At the same concentration, the hardness and chewiness of the KGM/WPI composite gel were significantly higher than those of the other two KGM/protein composite gels, among which the composite gel obtained by adding 8% WPI and 5% KGM heating-frozen (FWK4) had the greatest hardness and chewiness of 4338.07 g and 2313.76, respectively, and the springiness differences in all of the composite gels were small. In addition, the addition of protein increased the whiteness of the hybrid gels, with WPI having the most significant effect on the whiteness of the composite gels (whiteness increased from 30.25 to 62.80 as the concentration of WPI increased from 0 to 10%). Freezing increased composite gel hardness and chewiness, but reduced gel springiness and whiteness. Cluster analysis showed that the composite gel obtained by heating-cooling 8% WPI and 5% KGM (WK4) was very similar to the real tripe in terms of chewiness and whiteness, and WK4 had the highest sensory scores for color, tissue morphology, tactile sensation, taste, and odor. The acceptability score in terms of tissue morphology reached 4.3. Meanwhile, the characterization results of WK4 indicate the presence of large junction areas in the gel network. Fourier transform infrared spectroscopy (FTIR) analysis, X-ray diffraction, and intermolecular force contributions indicated that the incorporation of WPI promoted integral interactions, and that hydrophobic interactions and disulfide bonding played a key role in the WK4 composite gel system. Moreover, scanning electron microscopy (SEM) also showed that the combination of WPI and konjac glucan resulted in a more compact gel structure. This study is informative for the development of the field of bionic tripe processing.

Characterization of miRNA profiling in konjac-derived exosome-like nanoparticles and elucidation of their multifaceted roles in human health

Plant-derived exosome-like nanoparticles (ELNs) have demonstrated cross-kingdom capabilities in regulating intercellular communication, facilitating drug delivery, and providing therapeutic interventions in humans. However, the functional attributes of konjac-derived ELNs (K-ELNs) remain largely unexplored. This study investigates the isolation, characterization, and functional analysis of K-ELNs, along with the profiling and differential expression analysis of associated miRNAs in both K-ELNs and Konjac tissues. K-ELNs were successfully isolated and characterized from two konjac species using ultracentrifugation, followed by Transmission Electron Microscopy (TEM) and Nanoparticle Tracking Analysis (NTA). Small RNA sequencing identified a total of 3,259 miRNAs across all samples. Differential expression analysis revealed significant differences in miRNA profiles between K-ELNs and tissue samples. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) functional enrichment analysis of target genes provided insights into their roles in modulating pathways associated with diseases such as cancer and neurodegenerative disorders. Additionally, six miRNAs were selected for validation of sequencing results via RT-qPCR. The 5'RLM-RACE method was employed to validate the cleavage sites between differentially expressed miRNAs (DEMs) and their predicted target genes, further substantiating the regulatory roles of miRNAs in konjac. The findings of this study enhance our understanding of the molecular mechanisms underlying the biological functions and applications of K-ELNs, laying the groundwork for future research into their potential therapeutic roles in human health.

3D Printed Room Temperature Phosphorescence Materials Enabled by Edible Natural Konjac Glucomannan

Shaping room temperature phosphorescence (RTP) materials into 3D bodies is important for stereoscopic optoelectronic displays but remains challenging due to their poor processability and mechanical properties. Here, konjac glucomannan (KGM) is employed to anchor arylboronic acids with various π conjugations via a facile B─O covalent reaction to afford printable inks, using which full-color high-fidelity 3D RTP objects with high mechanical strength can be obtained via direct ink writing-based 3D printing and freeze-drying. The doubly rigid structure supplied by the synergy of hydrogen bonding and B─O covalent bonding can protect the triplet excitons; thus, the prepared 3D RTP object shows a striking lifetime of 2.14 s. The printed counterparts are successfully used for 3D anti-counterfeiting and can be recycled and reprinted nondestructively by dissolving in water. This success expands the scope of printable 3D luminescent materials, providing an eco-friendly platform for the additive manufacturing of sophisticated 3D RTP architectures.

Physicochemical and Rheological Properties of Degraded Konjac Gum by Abalone (Haliotis discus hannai) Viscera Enzyme

In the present study, a new degraded konjac glucomannan (DKGM) was prepared using a crude enzyme from abalone (Haliotis discus hannai) viscera, and its physicochemical properties were investigated. After enzymatic hydrolysis, the viscosity of KGM obviously decreased from 15,500 mPa·s to 398 mPa·s. The rheological properties analysis of KGM and DKGMs revealed that they were pseudoplastic fluids, and pseudoplasticity, viscoelasticity, melting temperature, and gelling temperature significantly decreased after enzymatic hydrolysis, especially for KGM-180 and KGM-240. In addition, the molecular weight of KGM decreased from 1.80 × 106 Da, to 0.45 × 106 Da and the polydispersity index increased from 1.17 to 1.83 after 240 min of degradation time. Compared with natural KGM, the smaller particle size distribution of DKGM further suggests enzyme hydrolysis reduces the aggregation of molecular chains with low molecular weight. FT-IR and FESEM analyses showed that the fragmented KMG chain did not affect the structural characteristics of molecular monomers; however, the dense three-dimensional network microstructure formed by intermolecular interaction changed to fragment microstructure after enzyme hydrolysis. These results revealed that the viscosity and rheological properties of KGM could be controlled and effectively changed using crude enzymes from abalone viscera. This work provides theoretical guidance for the promising application of DKGM in the food industry.

Improved physicochemical properties and in vitro digestion of walnut oil microcapsules with soy protein isolate and highly oxidized konjac glucomannan as wall materials

This study investigated the effect of the oxidation degrees of oxidized konjac glucomannan (OKGM) on the encapsulation efficiency (EE), physicochemical and in vitro digestive properties of soy protein isolate (SPI)-based microcapsules walnut oil using experimental and computational approaches. Microcapsules had the highest EE when the ratio of OKGM and SPI to oil was 2.5:1. With increasing the oxidation degree of OKGM, the EE of microcapsules was increased and the hygroscopicity was decreased. Molecular dynamics simulation results showed that SPI/oil/highly OKGM had relatively low binding energy (-4.03 × 106 kJ/mol) and strong electrostatic interactions, which may contribute to a higher EE and lower hygroscopicity of microcapsules, respectively. The oxidative stability of the oil was markedly improved by SPI and OKGM, and microcapsules prepared with SPI and highly OKGM had the highest in vitro digestion. This study provided theoretical support for broadening the application of microcapsules prepared with SPI and OKGM.

Functional validation of AaCaM3 response to high temperature stress in Amorphophallus albus

Amorphophallus is a perennial monocotyledonous herbaceous plant native to the southwestern region of China, widely used in various fields such as food processing, biomedicine and chemical agriculture. However, Amorphophallus is a typical thermolabile plant, and the continuous high temperature in summer have seriously affected the growth, development and economic yield of Amorphophallus in recent years. Calmodulin (CaM), a Ca2+ sensor ubiquitous in eukaryotes, is the most important multifunctional receptor protein in plant cells, which affects plant stress resistance by participating in the activities of a variety of signaling molecules. In this study, the key gene AaCaM3 for the Ca2+-CaM regulatory pathway was obtained from A. albus, the sequence analysis confirmed that it is a typical calmodulin. The qRT-PCR results demonstrated that with the passage of heat treatment time, the expression of AaCaM3 was significantly upregulated in A. albus leaves. Subcellular localization analysis revealed that AaCaM3 localized on the cytoplasm and nucleus. Meanwhile, heterologous transformation experiments have shown that AaCaM3 can significantly improve the heat tolerance of Arabidopsis under heat stress. The promoter region of AaCaM3 was sequenced 1,338 bp by FPNI-PCR and GUS staining assay showed that the promoter of AaCaM3 was a high-temperature inducible promoter. Yeast one-hybrid analysis and Luciferase activity reporting system analysis showed that the AaCaM3 promoter may interact with AaHSFA1, AaHSFA2c, AaHSP70, AaDREB2a and AaDREB2b. In conclusion, this study provides new ideas for further improving the signal transduction network of high-temperature stress in Amorphophallus.

Effects of different substrates on the growth and yield of Amorphophallus muelleri

Seven different substrates were prepared by mixing red soil, humus and river sand in different volume ratios and the growth and yield of Amorphophallus muelleri bulbils in different substrates was investigated. The growth of A. muelleri seedlings were tracked during the reproductive period, with measurements taken of indicators such as petiole length, petiole basal diameter and leaf size during the late period of leaf expansion. Number of surviving plants, weights and sizes of corms, and leaf bulbils were recorded after lodging. The results showed that there were differences in the physical and chemical properties of the seven substrates, but all met the growth requirements of A. muelleri. T1 (river sand), T2 (river sand: humus 1:1), T3 (humus), and T7 (river sand: humus: red soil 1:1:1) had higher emergence rates, reaching 95 %. T4 (humus: red soil 1:1) and T7 had better growth, with larger petiole and leaf sizes than other substrates. T3, T4, and T7 had higher yields, with a bulbil yield of 0.30 t hm-2 and a corm yield of 22.06 t hm-2. Compared to the use of a single substrate, whether river sand, humus, or red soil, the proportional mixture of the three test materials improved the physical structure and chemical composition of the substrate, contributing to the growth of A. muelleri. T7 (river sand: humus: red soil 1:1:1) was was found to be the best nursery substrate for A. muelleri.

Diversely regio-oxidative degradation of konjac glucomannan by lytic polysaccharide monooxygenase AA10 and generating antibacterial hydrolysate

Konjac glucomannan (KGM) hydrolysate exhibit various biological activities and health-promoting effects. Lytic polysaccharide monooxygenases (LPMOs) play an important role on enzymatic degradation of recalcitrant polysaccharides to obtain fermentable sugars. It is generally accepted that LPMOs exhibits high substrate specificity and oxidation regioselectivity. Here, a bacteria-derived SmAA10A, with chitin-active with strict C1 oxidation, was used to catalyse KGM degradation. Through ethanol precipitation, two hydrolysed KGM components (4 kDa (KGM-1) and 5 kDa (KGM-2)) were obtained that exhibited antibacterial activity against Staphylococcus aureus. In natural KGM, KGM-1, and KGM-2, the molar ratios of mannose to glucose were 1:2.19, 1:3.05, and 1:2.87, respectively, indicating that SmAA10A preferentially degrades mannose in KGM. Fourier-transform infrared spectroscopy and scanning electron microscopy imaging revealed the breakage of glycosylic bonds during enzymatic catalysis. The regioselectivity of SmAA10A for KGM degradation was determined based on the fragmentation behaviour of the KGM-1 and KGM-2 oligosaccharides and their NaBD4-reduced forms. SmAA10A exhibited diverse oxidation degradation of KGM and generated single C1-, single C4-, and C1/C4-double oxidised oligosaccharide forms. This study provides an alternative method for obtaining KGM degradation components with antibacterial functions and expands the substrate specificity and oxidation regioselectivity of bacterial LPMOs.

Enhanced hypoglycemic effects of konjac glucomannan combined with Polygonatum cyrtonema Hua polysaccharide in complete nutritional liquid diet fed type 2 diabetes mice

In our aging society, dysphagia and malnutrition are growing concerns, necessitating intervention. Liquid nutrition support offers a practical solution for traditional dietary issues, but it raises a key issue: the potential for post-meal glucose spikes impacting efficacy. This study examined the effects of supplementation of Polygonatum cyrtonema Hua polysaccharide (PCP), konjac glucomannan (KGM) and their combination on acute phase postprandial glycemic response and long-term glucose metabolism in T2DM mice on a complete nutritional liquid diet. KGM was more effective in reducing postprandial glucose response, while PCP was more prominent in ameliorating long-term glucose metabolism. The KGM-PCP combination demonstrated superior outcomes in fasting blood glucose, insulin, and glucose homeostasis. PCP and KGM also influenced the composition and abundance of the gut microbiome, with the H-PCP group showing optimal performance. Moreover, the KGM-PCP combination improved body weight, lipid homeostasis, and liver health the most. PCP potentially regulates glycemia through metabolic pathways, while KGM improves glycemic metabolism by reducing postprandial glucose levels in response to viscous intestinal contents. This research identifies the structure, viscosity properties, and hypoglycemic effects of KGM and PCP in complete nutritional liquid diet fed T2DM mice, enabling their strategic utilization as hypoglycemic components in nutritional administration and glycemic regulation.

The endophytic fungal community plays a crucial role in the resistance of host plants to necrotic bacterial pathogens

Konjac species (Amorphophallus spp.) are the only plant species in the world that are rich in a large amount of konjac glucomannan (KGM). These plants are widely cultivated as cash crops in tropical and subtropical countries in Asia, including China. Pectobacterium carotovorum subsp. carotovorum (Pcc) is one of the most destructive bacterial pathogens of konjac. Here, we analyzed the interactions between Pcc and susceptible and resistant konjac species from multiple perspectives. At the transcriptional and metabolic levels, the susceptible species A. konjac and resistant species A. muelleri exhibit similar molecular responses, activating plant hormone signaling pathways and metabolizing defense compounds such as phenylpropanoids and flavonoids to resist infection. Interestingly, we found that Pcc stress can lead to rapid recombination of endophytic microbial communities within a very short period (96 h). Under conditions of bacterial pathogen infection, the relative abundance of most bacterial communities in konjac tissue decreased sharply compared with that in healthy plants, while the relative abundance of some beneficial fungal communities increased significantly. The relative abundance of Cladosporium increased significantly in both kinds of infected konjac compared to that in healthy plants, and the relative abundance in resistant A. muelleri plants was greater than that in susceptible A. konjac plants. Among the isolated cultivable microorganisms, all three strains of Cladosporium strongly inhibited Pcc growth. Our results further elucidate the potential mechanism underlying konjac resistance to Pcc infection, highlighting the important role of endophytic microbial communities in resisting bacterial pathogen infections, especially the more direct role of fungal communities in inhibiting pathogen growth.

Structure, Modification Pattern, and Conformation of Hemicellulose in Plant Biomass

Different forms of plant biomass have been utilised for various applications in daily life and have gained increasing attention as replacements for fossil fuel-based products in the pursuit of a sustainable society. Plant cell walls, the primary carbon sink of plant biomass, have a high-order polysaccharide architecture consisting of cellulose, hemicelluloses, pectins, lignin and some proteins. Hemicelluloses are a group of polysaccharides that interact with cellulose, which is fundamental to the different properties and functionality of the plant cell walls. However, for industrial applications, the complex polysaccharide architecture poses a barrier to their efficient use. Understanding the molecular basis of plant cell walls - especially cellulose-hemicellulose interactions - is therefore critical to improving the utilisation of plant biomass. Recent research has revealed that the detailed structures, modification patterns, and conformation of hemicelluloses play an influential role in their interaction with cellulose. In this review, we discuss the latest insights into hemicelluloses across different forms of plant biomass and how their structures affect cell wall assembly. Additionally, we explore recent findings on how alterations in hemicellulose structure and modification patterns affect the usability of plant biomass, including the extractability of polysaccharides and the digestibility of biomass by glycoside hydrolases for biofuel production. Furthermore, we address unsolved questions in the field and propose future strategies to maximize the potential of plant biomass.

Silk nanofibrous scaffolds assembled by natural polysaccharide konjac glucomannan

Natural silk fibroin nanofibers (SNF) have recently attracted great attention in the field of biomaterials due to their excellent biocompatibility, outstanding mechanical properties, and biomimetic nanostructures. However, the poor structural stability of SNF assembly in aqueous conditions remains a major obstacle to their biomedical application. In this work, SNF scaffolds with extracellular matrix‐mimicking architecture and tunable properties were developed by using a small amount of konjac glucomannan (KGM) as a physical adhesive. Fourier transform infrared spectroscopy (FTIR) results revealed that KGM facilitated the formation of hydrogen bond networks between SNF as well as nanofibers/polysaccharide molecules, thereby reinforcing the interconnectivity between SNF. The water stability test showed that SNF scaffolds exhibited good structural stability in water when the mass ratio of KGM/SNF reached 2.5/100. Raising KGM content significantly enhanced the compression strength, modulus, and swelling ratio of the porous scaffold. Whereas, the nanofibrous morphology and porosity of the scaffolds were significantly sacrificed as KGM content exceeded 10% as evidenced by scanning electron microscopy (SEM) results. In vitro, cytocompatibility results also demonstrated the excellent biocompatibility of the biomimetic nanofibrous scaffolds, and the high porosity significantly enhanced cell viability. These results suggest that KGM‐reinforced SNF scaffolds may serve as promising candidates for biomaterial applications.

Unmasking Chemokine-Inducing Specificity in Oligosaccharide Biomaterial to Promote Hair Growth

Hair loss affects over 50 million people worldwide with limited therapeutic options. Despite evidence highlighting the vital role of local immune cells in regulating the life cycle of hair follicles (HFs), accurate regulation of immunocytes to directly promote hair growth remains unachieved. Here, inspired by the physiological feedback in the skin immunity to suppress microbe-triggered inflammation, an oligosaccharide biomaterial with "unmasked" specific activity is developed to recruit regulatory T (Treg ) cells around HFs, leading to accelerated hair growth in mice. By processing the glucomannan polysaccharide via controllable enzymatic cleavage, a series of oligosaccharide fractions with more specific chemokine-inducing functions is obtained. Notably, a hexasaccharide-based fraction (OG6) stimulates macrophages to selectively express Treg -chemoattractant C-C Motif Chemokine Ligand 5 (CCL5) through a mannose receptor-mediated endocytosis and NOD1/2-dependent signaling, as evidenced by molecular docking, inhibition assays, and a Foxp3-reporter mouse model. Intradermal delivery of OG6 to the depilated mouse skin promotes Treg mobilization around HFs and stimulates de novo regeneration of robust hairs. This study demonstrates that unmasking precise immunomodulatory functions in oligosaccharides from their parental polysaccharide can potentially solve the long-lasting dilemma with polysaccharide biomaterials that are widely renowned for versatile activities yet high heterogeneity, opening new avenues to designing glycan-based therapeutic tools with improved specificity and safety.

Inclusion of konjac glucomannan in pea protein hydrogels improved the rheological and in vitro release properties of the composite hydrogels

In this study, a composite hydrogel consisting of pea protein and konjac glucomannan (KG) was fabricated using three approaches, namely neutral, salt-set, and alkaline gelation. Hydrogels made from pea protein were brittle and weak. The addition of KG improved the elasticity and water holding capacity of the pea protein hydrogels. Concomitantly, a decrease in syneresis rate and swelling of the composite hydrogels was observed. The alkaline-set hydrogels exhibited the highest resilience to strain. Thixotropicity was found to be less pronounced for salt-set hydrogels. Sulphate had a greater positive effect on the structural recovery and negative effect on hysteresis area than chloride due to the greater salting-out effect of the sulphates. The addition of KG facilitated the formation of an interconnected structure with limited mobility of biopolymer chains. A sharp increase in G' and G" during the temperature ramp indicated the predominance of hydrophobic interactions towards the aggregation of biopolymers. The infrared spectra of the hydrogels revealed a change in secondary structure of proteins on addition of KG. A controlled in vitro release of riboflavin was observed in neutral and salt-set hydrogels. The alkaline-set hydrogels exhibited a prolonged gastric retention time, thereby establishing in vitro antacid activity in the gastric environment.

An efficient co-delivery system based on multilayer structural nanoparticles for programmed sequential release of resveratrol and vitamin D3 to combat dextran sodium sulfate-induced colitis in mice

Multilayer structural nanoparticles (MSNPs) fabricated by layer-by-layer self-assembly were used for the co-encapsulation of resveratrol (Res) and vitamin D3 (Vd). Res and Vd co-encapsulated MSNPs (Res-Vd-MSNPs) were evaluated by appearance, morphology, particle size, ζ potential and encapsulation efficiency (EE). The results showed that Res-Vd-MSNPs were spherical in shape with a particle size of 625.4 nm and a surface charge of +26.1 mV. The EE of Res and Vd was as high as 93.6 % and 90.8 %, respectively. Res-Vd-MSNPs exhibited better stability and lower degradation rate in simulated gastric fluid, allowing the programmed sequential release of Vd and Res in simulated intestinal fluid and simulated colonic fluid, which was also confirmed by in vivo fluorescence imaging of mice. In addition, Res-Vd-MSNPs effectively alleviated the clinical symptoms of dextran sulfate sodium salt (DSS)-induced colitis in mice, including weight loss, diarrhea and fecal bleeding, and it especially exerted a preventive effect on DSS-induced colon tissue damage and colon shortening. Furthermore, Res-Vd-MSNPs suppressed the expression of anti-inflammatory cytokines such as TNF-α, IL-1β and IL-6 and ameliorated DSS-induced oxidative damage, decreased colonic myeloperoxidase (MPO) and nitric oxide (NO) activities and elevated glutathione (GSH) level in DSS-treated mice. This study illustrated that MSNPs were potential carriers for developing the co-delivery system for the synergistic prevention and treatment of ulcerative colitis.

Active polysaccharides: a new roadmap for the prevention and treatment of food allergy

Active polysaccharides are extensively utilized in the fields of food and medicine because of their rich functional properties and structural plasticity. However, there are still few systematic studies and reviews on active polysaccharides for allergy. Allergy, especially food allergy, occurs frequently around the world and is related to a variety of factors such as age, genetics and dietary habits. Currently in medicine, avoiding allergens and desensitizing can effectively relieve allergy symptoms, but these are difficult to maintain over the long term and come with risks. Based on the supplementation of dietary nutrition to these two treatments, it has been discovered in recent years that the use of active ingredients from natural substances can effectively intervene in allergies. Considering the potential of active polysaccharides in this regard, we systematically characterize the latent patterns of polysaccharides in allergic symptoms and pathogenesis, including the aspects of gut, immunomodulatory, oxidative stress and signaling pathways, as well as the application prospect of them in allergy. It can be found that active polysaccharides have excellent anti-allergic potential, especially from the ocean. We believe that the active polysaccharides are associated with the treatment of allergic diseases, which may provide the benefits to allergy sufferers in the future.

Merging konjac glucomannan with other copolymeric hydrogels as a cutting-edge liquid raft system for dual delivery of etoricoxib and famotidine

This study aimed to formulate and evaluate a floating raft system for the co-delivery of etoricoxib (ETO) and famotidine (FAM) using a combination of glucomannan with natural/semi-synthetic polysaccharides. Formulation variables affect gelation lag time (GLT), floating lag time (FLT), and release percentage of drugs after 1-8 h, Stability, and viscosity parameters were evaluated. In vivo X-ray studies, followed by the pharmacokinetic study, were performed on human volunteers. Formulations exhibited pseudoplastic behavior for ease of swallowing. The optimum raft system (ORS) comprised 1% Na alginate, 0.1% Low Methoxyl (LM) pectin, 0.8% Konjac glucomannan (KGL), 1% Precirol, and 1% CaCO3. ORS exhibited rapid GLT and FLT (around 42 and 8 sec respectively) in 0.1 N HCl as well as controlled release of ETO (15% in 1 h and 82% in 8 h) and FAM (29% in 1 h and 85% in 8 h). Formulation stability with the absence of any drug-excipient interactions was observed. The X-ray imaging showed a promising buoyancy ability for approximately 8 h. Compared with marketed products, ORS showed superior relative bioavailability for both drugs. These findings revealed the successful preparation of a promising raft system with improved dual drug delivery.

Genus Amorphophallus: A Comprehensive Overview on Phytochemistry, Ethnomedicinal Uses, and Pharmacological Activities

The genus Amorphophallus belongs to the family Araceae. Plants belonging to this genus are available worldwide and have been used in traditional medicines since ancient times, mainly in Ayurveda and Unani medical practices. Amorphophallus species are an abundant source of polyphenolic compounds; these are accountable for their pharmacological properties, such as their analgesic, neuroprotective, hepatoprotective, anti-inflammatory, anticonvulsant, antibacterial, antioxidant, anticancer, antiobesity, and immunomodulatory effects, as well as their ability to prevent gastrointestinal disturbance and reduce blood glucose. Moreover, Amorphophallus species contain numerous other classes of chemical compounds, such as alkaloids, steroids, fats and fixed oils, tannins, proteins, and carbohydrates, each of which contributes to the pharmacological effects for the treatment of acute rheumatism, tumors, lung swelling, asthma, vomiting, abdominal pain, and so on. Additionally, Amorphophallus species have been employed in numerous herbal formulations and pharmaceutical applications. There has been no extensive review conducted on the Amorphophallus genus as of yet, despite the fact that several experimental studies are being published regularly discussing these plants' pharmacological properties. So, this review discusses in detail the pharmacological properties of Amorphophallus species. We also discuss phytochemical constituents in the Amorphophallus species and their ethnomedicinal uses and toxicological profiles.

Structurally Orientated Rheological and Gut Microbiota Fermentation Property of Mannans Polysaccharides and Oligosaccharides

Three mannan polysaccharides and their oligosaccharides were investigated in terms of physicochemical characteristics and effects on gut microbiota. Oligosaccharides from guar gum had the fastest fermentation kinetics for SCFAs generation at the initial stage, while the locust bean of both polymers and oligosaccharides demonstrated the lowest SCFAs through the whole fermentation process. In contrast, konjac gum steadily increased SCFAs and reached its maximum level at 24 h fermentation, indicating its fermentation character may be associated with its rheological properties. Compared to their corresponding polysaccharides, all the oligosaccharides demonstrated a faster fermentation kinetics, followed by an enriched abundance of propionate-producing bacterial Prevotella and a decreased abundance of Megamonas and Collinsella. Meanwhile, oligosaccharides reduced the Firmicutes/Bacteroidota ratio as well as the abundance of Bacteroidetes and Escherichia-Shigella. The fermentation of konjac substrate significantly promoted the abundance of butyrate-producing bacterial Faecalibacterium. In contrast, although the fermentation of locust bean and guar gum substrates benefited Bifidobacterium abundance due to their similar structure and monosaccharides composition, the fermentation of locust bean gum led to greater Bifidobacterium than the others, which may be associated with its higher mannose composition in the molecules. Interestingly, the partial hydrolysis of the three polysaccharides slightly reduced their prebiotic function.

Osteoclastogenesis Inhibitor and Antioxidant Properties of Konjac Glucomannan in a Periodontitis Mice Model: An In Vivo Study

Background

Periodontitis is an inflammatory disease caused by specific microorganisms that gradually damage the periodontal and tooth-supporting tissues, thereby reducing a person's quality of life. Periodontal disease is closely associated with high reactive oxygen species (ROS) levels, with a high receptor activator of nuclear factor kβ ligand (RANKL)/osteoprotegerin (OPG) ratio. Konjac glucomannan (KGM) is produced from the porang root, which has several properties. For example, it can reduce oxidative stress. The current study analyzed the osteoclastogenesis inhibitory and antioxidant properties of KGM based on histomorphometric findings, RANKL/OPG ratio, and ROS levels in the Swiss Webster mouse periodontitis model.

Methods

Eight-week-old male Swiss Webster mice were divided into the nonligation, nonligation + KGM, ligation + Porphyromonas gingivalis, and ligation + P. gingivalis + KGM groups. KGM suspension was administered for 14 days. Periodontitis induction was performed from 7th to 14th day. On the 14th day, maxillae, gingival, and gingival crevicular fluid samples were collected to assess the histomorphometry of bone damage, gene expression ratio of RANKL/OPG, and ROS protein levels.

Results

The periodontitis group pretreated with KGM presented with significantly reduced alveolar bone damage, RANKL/OPG ratio, and ROS level than without KGM group. KGM treatment had no harmful/toxic effects in mice.

Conclusion

Administration of KGM could act as an adjunctive in periodontal therapy by suppressing periodontal disease via osteoclastogenesis inhibitory and antioxidant properties.

Exploring the Antibacterial Potential of Konjac Glucomannan in Periodontitis: Animal and In Vitro Studies

Background and Objectives: Periodontitis is an inflammatory disease in the supporting tissues of the teeth caused by specific microorganisms or groups of microorganisms. P. gingivalis bacterium is the keystone pathogen in periodontitis, so even at low concentrations, it has a considerable influence on the oral community. Antimicrobials and antiplaque agents can be used as adjunctive therapy for periodontitis treatment. Konjac glucomannan (KGM), as a natural polysaccharide, has flavonoid (3,5-diacetyltambulin) and triterpenoids (ambylon) compounds that show antibacterial activity. This research aims to analyze the antibacterial activity of KGM on animal and in vitro periodontitis models. Materials and Methods: The animal study divided 48 mice into four groups (control, KGM, periodontitis, KGM + periodontitis). Mice were given an intervention substance by oral gavage from day 1 to day 14, periodontitis was induced on day 7, and decapitation was performed on day 14. Samples from the right maxillary jaw of mice were used for histological preparations and morphometrics analysis. In vitro studies were carried out by adding several concentrations of KGM (25, 50, and 100 μg/mL) into a planktonic P. gingivalis and P. gingivalis biofilm. Results: In the animal model, KGM could prevent alveolar bone loss in the periodontitis mice model, both in histologic and morphometrics assessments. In vitro, KGM had antibacterial activity against P. gingivalis with better bacteriostatic (15-23%) than bactericidal (11-20%) ability, proven by its ability to inhibit P. gingivalis proliferation. Conclusions: KGM can be considered to have the potential as an antibacterial agent to prevent periodontitis. The prevention of periodontitis may improve patient well-being and human quality of life.

Extracellular Matrix/Glycopeptide Hybrid Hydrogel as an Immunomodulatory Niche for Endogenous Cardiac Repair after Myocardial Infarction

The treatment of myocardial infarction (MI) remains a substantial challenge due to excessive inflammation, massive cell death, and restricted regenerative potential, leading to maladaptive healing process and eventually heart failure. Current strategies of regulating inflammation or improving cardiac tissue regeneration have limited success. Herein, a hybrid hydrogel coassembled by acellular cardiac extracellular matrix (ECM) and immunomodulatory glycopeptide is developed for endogenous tissue regeneration after MI. The hydrogel constructs a niche recapitulating the architecture of native ECM for attracting host cell homing, controlling macrophage differentiation via glycopeptide unit, and promoting endotheliocyte proliferation by enhancing the macrophage-endotheliocyte crosstalk, which coordinate the innate healing mechanism for cardiac tissue regeneration. In a rodent MI model, the hybrid hydrogel successfully orchestrates a proreparative response indicated by enhanced M2 macrophage polarization, increased angiogenesis, and improved cardiomyocyte survival, which alleviates infarct size, improves wall thicknesses, and enhances cardiac contractility. Furthermore, the safety and effectiveness of the hydrogel are demonstrated in a porcine MI model, wherein proteomics verifies the regulation of immune response, proangiogenesis, and accelerated healing process. Collectively, the injectable composite hydrogel serving as an immunomodulatory niche for promoting cell homing and proliferation, inflammation modulation, tissue remodeling, and function restoration provides an effective strategy for endogenous cardiac repair.

Perspectives of nanofibrous wound dressings based on glucans and galactans - A review

Wound healing is a complex and dynamic process that needs an appropriate environment to overcome infection and inflammation to progress well. Wounds lead to morbidity, mortality, and a significant economic burden, often due to the non-availability of suitable treatments. Hence, this field has lured the attention of researchers and pharmaceutical industries for decades. As a result, the global wound care market is expected to be 27.8 billion USD by 2026 from 19.3 billion USD in 2021, at a compound annual growth rate (CAGR) of 7.6 %. Wound dressings have emerged as an effective treatment to maintain moisture, protect from pathogens, and impede wound healing. However, synthetic polymer-based dressings fail to comprehensively address optimal and quick regeneration requirements. Natural polymers like glucan and galactan-based carbohydrate dressings have received much attention due to their inherent biocompatibility, biodegradability, inexpensiveness, and natural abundance. Also, nanofibrous mesh supports better proliferation and migration of fibroblasts because of their large surface area and similarity to the extracellular matrix (ECM). Thus, nanostructured dressings derived from glucans and galactans (i.e., chitosan, agar/agarose, pullulan, curdlan, carrageenan, etc.) can overcome the limitations associated with traditional wound dressings. However, they require further development pertaining to the wireless determination of wound bed status and its clinical assessment. The present review intends to provide insight into such carbohydrate-based nanofibrous dressings and their prospects, along with some clinical case studies.

Bio-adhesive and ROS-scavenging hydrogel microspheres for targeted ulcerative colitis therapy

Ulcerative colitis (UC) as an important type of inflammatory bowel disease is a chronic disease characterized by intestinal dyshomeostasis. The UC treatment is challenged by the insufficiency of drug delivery and retention. Herein, we fabricated an intrarectal formulation of olsalazine (Olsa)-loaded hydrogel microspheres (LDKT/Olsa) with good bio-adhesiveness and reactive oxygen species (ROS)-scavenging ability to enhance drug retention and therapeutic effect. Low methoxy pectin-dopamine conjugate/konjac glucomannan composite hydrogel microspheres (LDKT) with a size ranging from 10 to 100 μm were prepared by using Zn²⁺ and ROS-sensitive thioketal as crosslinkers. Upon intrarectal administration, the negatively charged and dopamine-functionalized hydrogel microspheres efficiently adhered to cationic surface of inflammatory mucosa, scavenging ROS and releasing Zn²⁺ and Olsa for antibacterial and anti-inflammatory effects. In the dextran sodium sulfate (DSS)-induced mouse UC model, the microspheres significantly reduced the levels of colonic ROS and pro-inflammatory cytokines, improved gut mucosal barrier integrity, and remarkably relieved colitis. Overall, the LDKT microspheres are promising carriers to deliver drugs for UC treatment.

Oral konjac glucomannan for prevention of ionizing radiation-induced injury by regulating gut microbiota and increasing short chain fatty acids

Ionizing radiation-induced injury commonly happens in radiotherapy, leading to damages of the hematopoietic and gastrointestinal systems. Radioprotective medications are mainly applied in hospitals, although only injections are available and their gut protection is limited. Here, oral konjac glucomannan (KGM), a natural macromolecule and soluble dietary fiber, was used against ionizing radiation-induced injury. The mice were fed with KGM (0.4 g/kg) for 3 days or injected with a clinical medication amifostine before 6.5 Gy γ-ray whole body irradiation (WBI) or 13 Gy whole abdominal irradiation (WAI). In the WBI experiments, KGM improved blood cell recovery and bone marrow cell proliferation in the femur and spleen, though its effect was weaker than or similar to that of amifostine. In the WBI experiments, the gut protection of KGM was similar to or a little better than that of amifostine, involving regenerated crypts numbers, villus length, and gut permeability. Moreover, KGM remarkably enhanced the survival rates of WBI and WAI mice, consistent with amifostine. KGM, as a prebiotic, enhanced gut microbiota abundance, probiotic numbers, and short chain fatty acid production, maintaining gut homeostasis. Moreover, KGM inhibited the apoptosis of irradiated human intestinal epithelial cells. KGM is a promising natural macromolecule against ionizing radiation-induced injury.

Different Response Mechanisms of Rhizosphere Microbial Communities in Two Species of Amorphophallus to Pectobacterium carotovorum subsp. carotovorum Infection

Soft rot is a widespread, catastrophic disease caused by Pectobacterium carotovorum subsp. carotovorum (Pcc) that severely damages the production of Amorphophallus spp. This study evaluated the rhizosphere bacterial and fungal communities in Pcc-infected and uninfected plants of two species of Amorphophallus, A. muelleri and A. konjac. Principal component analysis showed that the samples formed different clusters according to the Pcc infection status, indicating that Pcc infection can cause a large number of changes in the bacterial and fungal communities in the Amorphophallus spp. rhizosphere soil. However, the response mechanisms of A. muelleri and A. konjac are different. There was little difference in the overall microbial species composition among the four treatments, but the relative abundances of core microbiome members were significantly different. The relative abundances of Actinobacteria, Chloroflexi, Acidobacteria, Firmicutes, Bacillus, and Lysobacter were lower in infected A. konjac plants than in healthy plants; in contrast, those of infected A. muelleri plants were higher than those in healthy plants. For fungi, the relative abundances of Ascomycota and Fusarium in the rhizosphere of infected A. konjac plants were significantly higher than those of healthy plants, but those of infected A. muelleri plants were lower than those of healthy plants. The relative abundance of beneficial Penicillium fungi was lower in infected A. konjac plants than in healthy plants, and that of infected A. muelleri plants was higher than that of healthy plants. These findings can provide theoretical references for further functional research and utilization of Amorphophallus spp. rhizosphere microbial communities in the future.

Nanocoating-konjac application as postharvest handling to extend the shelf life of Siamese oranges

Siamese orange fruit is very popular today, driven by the increasing public demand or healthy food. Siamese oranges contain bioactive phenolic compounds, carotenoids, vitamins, minerals, and fiber which are good for health. The weakness of Siamese oranges is their quality declines quickly and their short shelf life. Postharvest handling with the application of coatings from natural ingredients to extend the shelf life of orange fruits is currently needed to reduce the use of synthetic materials. Natural ingredients that have the potential to be used as base materials for coatings are konjac tubers because they contain glucomannan polysaccharides and bioactive compounds that can form coatings. The purpose of this study was to determine the effect of nanocoating-konjacon the shelf life of Siamese oranges. The research began with the preparation of the nanocoating-konjac formula as the main ingredient of the nanocoating and the application of the nano coating-konjac on the surface of Siamese oranges. This study used a completely randomized two-factor design, namely nanocoating-konjac application (without coating, coating, and nanocoating) and storage time (0, 5, 10, and 15 days), three replications. Variables observed: Weight loss, number of damaged fruits, color, texture, acidity, total soluble solids, water content, vitamin C, and total plate count. The data obtained was tested for diversity with SPSS, if it shows differences the test is continued with Duncan's Multiple Range Test. The conclusion of this research is the application of nanocoating-konjac, coating-konjac and without coating on Siamese oranges to determine the effect of weight loss, number of damaged fruits, color, texture, acidity, total dissolved solids, water content, vitamin C, and total plate count during storage. This research recommends that the application of nanocoating-konjac as postharvest handling can extend the shelf life of Siamese oranges until the 10th days.

Synergy of antioxidant and M2 polarization in polyphenol-modified konjac glucomannan dressing for remodeling wound healing microenvironment

Effective skin wound healing and tissue regeneration remain a challenge. Excessive/chronic inflammation inhibits wound healing, leading to scar formation. Herein, we report a wound dressing composed of KGM-GA based on the natural substances konjac glucomannan (KGM) and gallic acid (GA) that accelerates wound healing without any additional drugs. An in vitro study showed that KGM-GA could not only stimulate macrophage polarization to the anti-inflammatory M2 phenotype but also decrease reactive oxygen species (ROS) levels, indicating excellent anti-inflammatory properties. Moreover, in vivo studies of skin wounds demonstrated that the KGM-GA dressing significantly improved wound healing by accelerating wound closure, collagen deposition, and angiogenesis. In addition, it was observed that KGM-GA regulated M2 polarization, reducing the production of intracellular ROS in the wound microenvironment, which was consistent with the in vitro experiments. Therefore, this study designed a multifunctional biomaterial with biological activity, providing a novel dressing for wound healing.

Effects of Glucomannan Supplementation on Type II Diabetes Mellitus in Humans: A Meta-Analysis

The hypoglycemic and lipid-lowering effects of glucomannan are widely known, and it is a potential effective treatment for type II diabetes. In this study, we evaluated the effects of glucomannan supplementation on blood-lipid-related indicators, blood-glucose-related indicators, blood pressure (BP), and body weight (BW) in patients suffering from type II diabetes. We searched databases including PubMed, Cochrane, the comprehensive biomedical research database (Embase), Web of Science, and China National Knowledge Infrastructure (CNKI) for literature on glucomannan and type II diabetes. Six randomized controlled trials (RCTs) were eligible (n = 440 participants) to be included in our analysis. Glucomannan not only reduced the total cholesterol (TC) (MD -0.38 [95% CI: -0.61, -0.15], p = 0.001) and low-density lipoprotein (LDL) levels (MD -0.35 [95% CI: -0.52, -0.17], p < 0.0001) compared with the control group, but also reduced the fasting blood glucose (FBG) (MD -1.08 [95% CI: -1.65, -0.50], p = 0.0002), 2 h postprandial blood glucose (P2hBG) (MD -1.92 [95% CI: -3.19, -0.65], p = 0.003), fasting insulin (FINS) (MD -1.59 [95% CI: -2.69, -0.50], p = 0.004), and serum fructosamine (SFRA) levels (SMD -1.19 [95% CI: -1.74, -0.64], p < 0.0001). Our analysis indicates that glucomannan is an effective nutritional intervention for type II diabetes.