BACKGROUND:Commercially available edible mushroom polysaccharide (EMP) products often contain impurities such as maltodextrin, proteins and polyphenols, which interfere with accurate quality evaluation. This study aimed to establish a pretreatment protocol to purify these products and investigate the structure-activity relationships of their antioxidant activities. RESULTS:Physicochemical analysis revealed that maltodextrin interfered with polysaccharide quantification. A pretreatment protocol using glucoamylase for maltodextrin removal and potassium ferrocyanide/zinc acetate for deproteinization was optimized. The purified crude polysaccharides were heteroglycans with broad molecular weight distributions. All nine EMPs exhibited antioxidant capacity, with Grifola frondosa (Dicks.) Grey polysaccharide and Cordyceps militaris (L.ex Fr.) Link polysaccharide showing the most potent activities. Structure-activity relationship analysis indicated that antioxidant activity was positively correlated with the contents of mannose, galactose, arabinose, fucose and uronic acid. CONCLUSION:The proposed pretreatment reduced interference from starch-based substances and proteins in the tested commercial products. Residual protein and phenolic-compound contents were associated with several in vitro antioxidant indicators, suggesting that coexisting components may influence the measured responses. This study provides a theoretical basis for elucidating the antioxidant mechanisms of polysaccharides and highlights the need for standardized pretreatment in quality evaluation. © 2026 Society of Chemical Industry.

EMPs are widely used for their food-medicine characteristics and bioactivities. However, the lack of unified standards has resulted in inconsistent product quality. In this study, crude polysaccharides were extracted and purified from five EMP products purchased from the Chinese market, namely, polysaccharides from Wolfiporia cocos (F.A. Wolf) Ryvarden & Gilb. polysaccharide (WCP), Agaricus blazei Murill polysaccharide (ABP), Flammulina velutipes polysaccharide (FVP), Cordyceps militaris (L. ex Fr.) Link polysaccharide (CMP), and Tremella fuciformis Berk polysaccharide (TFP). The physicochemical properties, structural elucidation, in vitro digestion, and gut microbiota modulatory activities of the purified polysaccharides were then examined. The polysaccharides consisted of heteroglucans containing galactose, mannose, fucose, xylose, and arabinose. After simulated gastrointestinal digestion, all five polysaccharides showed adequate anti-digestive properties, with WCP and CMP outperforming the others. Fecal fermentation experiments indicated that gut microbiota could use these polysaccharides to produce short-chain fatty acids. The polysaccharides significantly increased the relative abundance of Actinomycetota and Bacillota, while decreasing Pseudomonadota and Fusobacteriota. ABP and CMP regulatory effects were stronger than those of inulin. The findings can help establish a quality evaluation system for EMPs and provide preliminary evidence for gut microbiota modulation activity of ABP and CMP in functional foods.

Nucleosides and polysaccharides are the main bioactive ingredients of Cordyceps genus. Nucleosides shows significant differences in different Cordyceps species. However, the differences of polysaccharides have not been decoded. Here, the structure characters of polysaccharides including molecular weight (Mw) distribution, compositional monosaccharides and glycosidic linkage types were compared in C. sinensis (CS), C. militaris (CM), silkworm-hosted C. militaris (SCM) and Cordyceps fermented products (CSF). Compositional monosaccharides including mannose, glucose and galactose, and 1,4-Glcp glycosidic linkage were found abundant in Cordyceps species. Chemometric analysis showed that Cordyceps exhibit significant differences in structural information especially glycosidic linkage types. Besides, polysaccharides in CS and CSF-4 had obviously strong capacity of stimulating phagocytic, NO production and cytokines secretion. Gray relational analysis and Pearson correlation analysis were performed to further investigate the relationship between key polysaccharide structure and immunomodulatory activities. The results indicated that polysaccharides with relatively large number of 1, 4-Glcp and Mw in range of 7.16 × 106 Da-7.99 × 107 Da and 1.43 × 104 D-6.94 × 105 Da probably contributed to its immunomodulatory activities. The chemical and biological evaluation of natural and various cultured cordyceps in this study is useful for understanding and regulating the quality of cultured Cordyceps.

Addressing microbial imbalance is a critical therapeutic strategy for ulcerative colitis (UC). Natural polysaccharides have attracted increasing attention for their potential in UC prevention. In this study, we purified and characterized an acidic heteropolysaccharide (LBP 2-1) from Lycium barbarum L. and systematically evaluated its therapeutic effects on UC. Monosaccharide composition analysis combined with methylation analysis and NMR spectroscopy revealed that LBP 2-1 possesses a complex structure. The backbone is →2)-α-L-Rhap-(1 → 4)-α-D-GalAp-(1 → 6)-β-D-Galp-(1 → and branched at the O-3/O-4 positions of →3,6)-β-D-Galp-(1 → and →2,4)-α-L-Rhap-(1 →. The branch chains consist of →5)-α-L-Araf-(1 →, →3,5)-α-L-Araf-(1 →, →3)-β-D-Galp-(1 →, β-D-Galp-(1 →, and α-L-Araf-(1 →. Particularly, LBP 2-1 relieved the symptoms of weight loss and colon shortening, and reduced DAI and histopathological scores in UC mice. Furthermore, LBP 2-1 alleviated UC symptoms by enhancing microbiota diversity, increasing the abundance of beneficial bacteria (e.g., norank_f__Muribaculaceae), and reducing harmful bacteria (e.g., Bacteroides). These findings elucidate the structural characteristics of a novel acidic polysaccharide and confirm its therapeutic potential for UC treatment.

Polysaccharides are important soluble dietary fibers in food, and their nutritional function is closely related to their structure. In this study, five common food-derived polysaccharides (pectin, fucoidan, arabinogalactan, inulin and glucan) were extracted, purified, and characterized in terms of their molecular weight distribution, monosaccharide composition and ratio, as well as glycosidic bond types. The results showed that their molecular weights vary greatly. Besides, pectin and arabinogalactan even exhibiting notable complexity and high branching, which may contribute to the differences in their activities. In vitro fermentation experiments combined with 16S rRNA gene sequencing revealed that pectin, inulin and arabinogalactan could significantly promote the growth of gut microbiota. Pectin and fucoidan could increase the production of short-chain fatty acids (SCFAs). Meanwhile, pectin and arabinogalactan can also significantly enhance the diversity and richness of the gut microbiota. Notably, pectin and arabinogalactan displayed higher activity, potentially attributable to their structural complexity and extensive branching. Mono-culture and co-culture experiments further elucidated the cross-feeding of gut microbiota in degrading polysaccharides, confirming that co-culture did not significant affect the growth of Bacteroides but markedly promoted the growth of Lactobacillus, suggesting that polysaccharides can be degraded and utilized step by step through the cooperation between intestinal microbiota. This study contributes to the development of structurally defined polysaccharides for more precise regulation of the intestinal microbiota, offering scientific dietary guidance for humans and providing a critical foundation for the advancement of intestinal probiotics and substance with prebiotic activity.

Polysaccharides from 18 batches of Atractylodes lancea (AL), A. chinensis (AC) and A. macrocephala (AM) were compared based on molecular weight (MW) distribution, monosaccharide composition and content, and glycosidic linkage type. Results showed that polysaccharides from AL, AC and AM mainly exhibited three molecular weight fractions, and the average Mw of fraction 1 and 2 in AM is 4.0-1.8 times of AL and AC. Therefore, AM could be distinguished from AL and AC based on large Mw. 7 kinds of monosaccharides were released from AL, AC and AM, and the average content of released monosaccharides in AC (141.2 mg/g) was obviously higher than that in AL (106.4 mg/g) and AM (121.0 mg/g). AC could be distinguished from AL based on monosaccharides content. 1,2-Fruf is the dominant type of glycosidic linkage, which indicated that fructan is abundant. The higher proportion of 1,4-Galp residues after reduction in AM revealed that pectin-type polysaccharides are relatively abundant in AM. Combined with chemometric analysis, the glycosidic linkage can distinguish AL, AC and AM clearly, and 1, 4-Galp and 1,2,4-Rhap residues were confirmed as the differential glycosidic linkages. This study was helpful in understanding the varied functions of different Atractylodes spp. based on chemical composition.

Dendrobium is a famous edible and medicinal plants, and polysaccharides are their main bioactive components. Polysaccharides from five species, namely, DO (Dendrobium officinale Kimura et Migo), DH (Dendrobium huoshanense C. Z. Tang et S. J. Cheng), DNL (Dendrobium nobile Lindl.), DFH (Dendrobium fimbriatum Hook.), and DCL (Dendrobium chrysanthum Lindl.), were compared based on molecular weight (Mw), monosaccharide composition, and glycosidic bond types. The results showed that Dendrobium polysaccharides (DPs) contain relatively simple compositional monosaccharides and mainly consist of mannose (Man) and glucose (Glc), along with small amounts of arabinose (Ara), xylose (Xyl), and galactose (Gal). The Am/Ag (the ratio of Man to Glc) values in DO, DH, and DNL polysaccharides were 3.23, 3.81, and 3.88, while those in DFH and DCL were 0.45 and 0.81. DPs are mainly composed of →4)Manp(1→ and →4)Glcp(1→, but their molar ratios were different. →4)Manp(1→ and →4)Glcp(1→ ratios were 2.85, 2.92, 1.50, 1.45, and 1.05 in DO, DH, DNL, DFH, and DCL, respectively. Hierarchical cluster analysis (HCA) showed that there were significant differences in structural information, especially in glycosidic bond types and proportions. DH, DO, and DCL were clustered into different groups based on glycosidic bond types and proportions, respectively. Moreover, the five species of Dendrobium could significantly inhibit NO production and apoptosis induced by LPS in RAW 264.7, especially DH. The results of a correlation analysis of structure and anti-inflammatory activity showed that polysaccharides with a high →4)Manp(1→/→4)Glcp(1→ ratio and a molecular weight distribution between 3.343 × 105 Da and 13.540 × 105 Da had better anti-inflammatory activity. The results indicated that the quality evaluation of Dendrobium in clinical applications should investigate molecular weight and the composition of the glycoside bond types and proportions to ensure the consistency of curative effects.

As effective methods to accurately and rapidly detect protamine remains a major challenge, here we present a fluorescent protein chromophore-based probe (IDL-FP) utilizing twisted-intramolecular charge transfer (TICT) to detect protamine. The introduction of an electron-donor group 4-dimethylaminobenzaldehyde extends the emission wavelength of IDL-FP to the red region. The deprotection of t-butyloxy carbonyl groups can then generate an electronegative carboxyl group, which promotes the binding to protamine via electrostatic attraction. Thus, IDL-FP is sensitive and specific towards protamine and can serve as a highly selective detector for protamine with a detection limit as low as 8.87 ng/mL. As IDL-FP exhibited good stability in physiological pH environment, we successfully apply IDL-FP to detect spiked-in protamine in human serum. In summary, probe IDL-FP is a promising tool for the quantitative determination of protamine. In this research, a new TICT probe (IDL-FP) was designed for sensitive detection of protamine. The introduction of indole-3-carboxaldehyde and 4-dimethylaminobenzaldehyde gave IDL-FP both an electron-donor and electron-acceptor, which urged the complete intramolecular charge transfer and a large stokes shift, allowing IDL-FP to process minimal background noise and excellent biocompatibility. Additionally, protamine can directly induce the aggregation of IDL-FP caused by electrostatic attraction. In this way, the turn-on detection of protamine was achieved and the detection limit was as low as 8.87 ng mL-1, which showed a better sensitivity and higher stability. As IDL-FP exhibited good stability in physiological pH environment, we successfully applied IDL-FP to detect spiked-in protamine in human serum. In summary, probe IDL-FP is a promising tool for the quantitative determination of protamine for potential clinical usage. image

Codonopsis pilosula is a famous edible and medicinal plants, in which polysaccharides are recognized as one of the important active ingredients. A neutral polysaccharide (CPP-1) was purified from C. pilosula . The structure was characterized by HPSEC-MALLS-RID, UV, FT -IR, GC-MS, methylation analysis, and NMR. The results showed that CPP-1 was a homogeneous pure polysaccharide, mainly containing fructose and glucose, and a small amount of arabinose. Methylation analysis showed that CPP-1 composed of -*1)-Fru f -(2-*, Fru f- (1-* and Glc p -(1-* residues. Combined the NMR results the structure of CPP-1 was confirmed as alpha-D-Glc p -(1 -* [2)-beta-D-Fru f -(1 -* 2)beta-D-Fru f -(1] 26 -* 2)-beta-D-Fru f with the molecular weight of 4.890 x 10 3 Da. The model of AML12 hepatocyte fat damage was established in vitro . The results showed that CPP-1 could increase the activity of SOD and CAT antioxidant enzymes and reduce the content of MDA, thus protecting cells from oxidative damage. Subsequently, the liver protective effect of CPP-1 was studied in the mouse model of nonalcoholic fatty liver disease (NAFLD) induced by the high-fat diet. The results showed that CPP-1 significantly reduced the body weight, liver index, and body fat index of NAFLD mice, and significantly improved liver function. Therefore, CPP-1 should be a potential candidate for the treatment of NAFLD.

Monosaccharide composition analysis is essential to the structural characterization and research into the biological activity of polysaccharides. In this study, a systematic comparison was performed among commonly used monosaccharide composition analysis methods, including colorimetric and chromatographic methods. These were tested on 16 aldoses, ketoses, alditols, amino sugars, and uronic acids. Furthermore, the effect of hydrolysis methods was also investigated. The results showed that the phenol sulfuric acid method is greatly affected by the type of monosaccharide that is used as the reference substance. The determination of uronic acid using sulfuric acid carbazole is less affected by neutral sugars than that method using m-hydroxybiphenyl. The high-performance thin-layer chromatography (HPTLC) method can simultaneously analyze multiple samples and accurately determine the type of uronic acid. High-performance liquid chromatography (HPLC) can provide a good qualitative and quantitative analysis of aldose, amino sugars, and uronic acids, while gas chromatography–mass spectrometry (GC-MS) can detect aldose, ketose, and alditols. Fructose was detected in a large amount in inulin and Codonopsis pilosula after one-step hydrolysis, while it was totally destroyed in two-step hydrolysis. The release of galacturonic acid significantly increased after two-step hydrolysis in pectin and Lycium barbarum, which indicated that one-step hydrolysis is not enough for acidic polysaccharides. The results of this study are beneficial for selecting appropriate hydrolysis and analysis methods in order to accurately analyze the monosaccharide compositions of natural polysaccharides.

For many bioactive chemicals contained in traditional Chinese medicines, pressurized liquid extraction has become a preferred green extraction method. This review goes over the extraction principles and how to improve the extraction efficiency by optimizing the extraction parameters. The use of various solvent combinations and other extraction additives to improve extraction efficiency is explored. The utilization of combined and hyphenated sample preparation and analytical procedures, as well as the dynamic mode of extraction in pressurized liquid extraction, are discussed. This review also summarized applications that used pressurized liquid extraction to enrich different functional components from medicinal herbs.

The selection of the matrix is crucial for matrix assisted laser desorption ionization mass spectrometry imaging (MALDI-MSI). This work successfully synthesized metal-organic framework (MOF) matrices to address the limitations on the application of traditional organic matrices in the study of small molecule compositions, and Ti-based MOF nanosheets were screened as matrices for imaging the hepatotoxic components of Polygonum multiflorum. Comparison between six MOF materials and traditional organic matrices showed that Ti-based MOF nanosheets have less background interference, significant stability, and high salt resistance. The imaging results indicated that the main components of Polygonum multiflorum, free anthraquinone and stilbene glycoside have unique spatial distribution characteristics. Successful application of the synthesized Ti-based MOF nanosheets in mass spectrometry imaging improved the detection ability of mass spectrometry imaging in the small molecule field, and spatiotemporal content changes of hepatotoxic components in Polygonum multiflorum during the steaming process were observed, providing a scientific basis for steaming.

Dendrobium huoshanense is a famous edible and medicinal herb, and polysaccharides are the main bioactive component in it. In this study, response surface methodology (RSM) combined with a Box–Behnken design (BBD) was used to optimize the enzyme-assisted extraction (EAE), ultrasound–microwave–assisted extraction (UMAE), and hot water extraction (HWE) conditions and obtain the polysaccharides named DHP-E, DHP-UM, and DHP-H. The effects of different extraction methods on the physicochemical properties, structure characteristics, and bioactivity of polysaccharides were compared. The differential thermogravimetric curves indicated that DHP-E showed a broader temperature range during thermal degradation compared with DHP-UM and DHP-H. The SEM results showed that DHP-E displayed an irregular granular structure, but DHP-UM and DHP-H were sponge-like. The results of absolute molecular weight indicated that polysaccharides with higher molecular weight detected in DHP-H and DHP-UM did not appear in DHP-E due to enzymatic degradation. The monosaccharide composition showed that DHPs were all composed of Man, Glc, and Gal but with different proportions. Finally, the glycosidic bond types, which have a significant effect on bioactivity, were decoded with methylation analysis. The results showed that DHPs contained four glycosidic bond types, including Glcp-(1→, →4)-Manp-(1→, →4)-Glcp-(1→, and →4,6)-Manp-(1→ with different ratios. Furthermore, DHP-E exhibited better DPPH and ABTS radical scavenging activities. These findings could provide scientific foundations for selecting appropriate extraction methods to obtain desired bioactivities for applications in the pharmaceutical and functional food industries.

Edible and medicinal plants (EMPs) are widely used but are easily infected by harmful fungi which produce mycotoxins. Herein, 127 samples from 11 provinces were collected to investigate 15 mycotoxins based on geographic, demographic, processing, and risk characteristics. A total of 13 mycotoxins were detected, and aflatoxin B1 (0.56~97.00 μg/kg), deoxynivalenol (9.41~1570.35 μg/kg), fumonisin B1 (8.25~1875.77 μg/kg), fumonisin B2 (2.74~543.01 μg/kg), ochratoxin A (0.62~19.30 μg/kg), and zearalenone (1.64~2376.58 μg/kg) occurred more frequently. Mycotoxin levels and species were significantly different by region, types of EMPs, and method of processing. The margin of exposure (MOE) values was well below the safe MOE (10,000). AFB1 exposure from Coix seed and malt consumption in China was of high health concern. The hazard Index (HI) method showed the range of 113.15~130.73% for malt, indicating a public health concern. In conclusion, EMPs should be concerned because of the cumulative effects of co-occurred mycotoxins, and safety management strategies should be developed in follow-up studies.

Metal organic frameworks (MOFs) with their large surface area and numerous active sites have attracted significant research attention. Recently, the application of MOFs for the catalytic degradation of organic pollutants has provided effective solutions to address diverse environmental problems. In this review, the latest progress in MOF-based removal and degradation of organic pollutants is summarized according to the different roles of MOFs in the removal reaction systems, such as physical adsorbents, enzyme-immobilization carriers, nanozymes, catalysts for photocatalysis, photo-Fenton and sulfate radical based advanced oxidation processes (SR-AOPs). Finally, the opportunities and challenges of developing advanced MOFs for the removal of organic pollutants are discussed and anticipated. Graphical Abstract

Immunoassay-based techniques are important on-site screening tools for the detection of mycotoxins in cereals. This study aims to evaluate the trueness, precision, repeatability and cross-reactivity of commercially available test strips, ELISA kits and UHPLC-MS/MS on analyzing zearalenone, ochratoxin A, deoxynivalenol, T-2 toxin and fumonisin B1. The results showed that false negative rate (25.7 %-37.4 %) of all tested mycotoxins by test strips was higher than the false positive rate (0 %-31.0 %). The repeatability of ELISA kits at the declared LOD dispersed from -85.7 % to +98.4 %. ELISA kits were more accurate at 50 % of the maximum residue limit (MRL) of mycotoxins than 150 % and 200 %. All the tested deoxynivalenol/zearalenone derivatives had cross-reactivity with different level, and sample matrix could reinforce this overestimation of target mycotoxin. This study emphasized that higher-quality antibody screening and more analytical performance investigations are need to address for on-site detection of mycotoxins in the future.

A highly sensitive surface-enhanced Raman spectroscopy (SERS) aptasensor for multiplex mycotoxins detection was developed based on aptamer-functionalized photonic microsphere array. Gold nanoparticles (AuNPs) were grafted covalently onto the silica photonic crystal microsphere (SPCM) to fabricate the SERS active substrate, on which the near-field enhancement can reach to 20 times analyzed by the simulation electric field distribution. Two dyes of 5,5 '-dithiobis (2-nitrobenzoic acid) (DTNB) and nile blue A (NBA) were employed to make the SERS nanotags on AuNPs that were modified with corresponding anti-aptamer sequences. A SERS assay system was established based on the competitive reaction between the anti-aptamer on SERS nanotags and the target mycotoxin towards the aptamer on SPCM. The developed method showed a linear relationship in the range of 0.01-100 ng/mL for aflatoxin B-1 (AFB(1)) and 0.001-10 ng/mL for ochratoxin A (OTA), and a low limit of detection of 0.36 pg/mL for AFB(1) and 0.034 pg/mL for OTA. The accuracy of such method was confirmed by its good recovery ratio and high repeatability, and further verified by the classic enzyme-linked immunosorbent assay using naturally mycotoxins contaminated edible samples. The established method has a great application potential for screening mycotoxins rapidly with high sensitivity, low-cost and high throughput in the fields of food and traditional Chinese herb.

A novel MOF@HOF composite that can serve as a matrix for analysis of small molecules by MALDI-TOF-MS was fabricated through a simple solvothermal method. Taking falvonoids as an example, this composite/matrix presents high desorption/ionization efficiency, low background interference, high salt tolerance, and satisfactory signal reproducibility for MALDI-TOF-MS analysis.

Cordyceps genus are famous fungus both in edible and medicinal use. In this study, the nucleosides, nucleobases and characters of polysaccharides were compared in four species of Cordyceps including C. sinensis (CS), C. militaris (CM), silkworm-hosted C. militaris (SCM) and Cordyceps fermented products (CSF). And the immunomodulatory activities of polysaccharides were also investigated. The results showed that the nucleosides and nucleobases composition varied significantly. Polysaccharides in CS had obviously strong capacity of stimulating phagocytic, NO production and cytokines secretion than other Cordyceps, except one fermentation products (CSF-4). Simultaneously, CS and CSF-4 had higher proportion of 4-linked Galp residues. Furthermore, glycosidic bond types show a stronger ability to distinguish different kinds of Cordyceps. This study is helpful to better understand the difference of Cordyceps. It is also indicated that comprehensive structure character of polysaccharides should be considered when evaluate the activity or quality control of polysaccharides in foods and medicines.

A polysaccharide (ALP-1) extracted from Atractylodes lancea (Thunb.) DC. was carboxymethylated (C-ALP-1), phosphorylated (P-ALP-1) and acetylated (A-ALP-1) to improve its physicochemical properties and bioactivities. The solubility of all derivatives was increased, and the solubility of A-ALP-1 increased to 137.5 mg/mL, which was much higher than the solubility of ALP-1 (15.0 mg/mL). The results of HPSEC-MALLS-RID showed that the molecular weight of polysaccharides was slightly increased after the modification, and the root mean square radius of rotation (Rz) and morphology of polysaccharides in solution were also changed. The scanning electron microscopy (SEM) and X-ray diffraction (XRD) results confirmed that the surface morphology of ALP-1 changed dramatically and the crystallinity decreased after structural modification. From thermal analysis results, the T50 of ALP-1, C-ALP-1, P-ALP-1 and A-ALP-1 were 281.34, 292.14, 333.75 and 298.70 °C, which showed that derivatives had stronger thermal stability than ALP-1. The immunomodulatory activity studies displayed that P-ALP-1 showed the best ability to stimulate RAW264.7 macrophages to release NO, and A-ALP-1 showed the best capacity to stimulate TNF-α and IL-6 releasing. These results indicated that chemical modification could enhance the solubility, the thermal stability and immunomodulatory activity of polysaccharides, which is beneficial for the development and utilization of natural polysaccharides.