Physicochemical, functional, and biological properties of water-soluble polysaccharides from Rosa roxburghii Tratt fruit

Polysaccharides in fruits: Biological activities, structures, and structure-activity relationships and influencing factors-A review

Fruits are a rich source of polysaccharides, and an increasing number of studies have shown that polysaccharides from fruits have a wide range of biological functions. Here, we thoroughly review recent advances in the study of the bioactivities, structures, and structure-activity relationships of fruit polysaccharides, especially highlighting the structure-activity influencing factors such as extraction methods and chemical modifications. Different extraction methods cause differences in the primary structures of polysaccharides, which in turn lead to different polysaccharide biological activities. Differences in the degree of modification, molecular weight, substitution position, and chain conformation caused by chemical modification can all affect the biological activities of fruit polysaccharides. Furthermore, we summarize the applications of fruit polysaccharides in the fields of pharmacy and medicine, foods, cosmetics, and materials. The challenges and perspectives for fruit polysaccharide research are also discussed.

Chemical diversity, traditional uses, and bioactivities of Rosa roxburghii Tratt: A comprehensive review

Rosa roxburghii Tratt (RRT), known as chestnut rose, has been a subject of growing interest because of its diverse chemical composition and wide range of traditional uses. This comprehensive review aimed to thoroughly examine RRT, including its traditional applications, chemical diversity, and various bioactivities. The chemical profile of this plant is characterized by the presence of essential nutrients such as vitamin C (ascorbic acid), flavonoids, triterpenes, organic acids, tannins, phenolic compounds, polysaccharides, carotenoids, triterpenoids, volatile compounds, amino acids, and essential oils. These constituents contribute to the medicinal and nutritional value. Additionally, we explore the multifaceted bioactivities of RRT, including its potential as an anticancer agent, antioxidant, antiaging agent, antiatherogenic agent, hypoglycemic agent, immunoregulatory modulator, radioprotective agent, antimutagenic agent, digestive system regulator, anti-inflammatory agent, cardioprotective agent, and antibacterial agent, and its intriguing role in modulating the gut microbiota. Furthermore, we discuss the geographical distribution and genetic diversity of this plant species and shed light on its ecological significance. This comprehensive review provides a holistic understanding of RRT, bridges traditional knowledge with contemporary scientific research, and highlights its potential applications in medicine, nutrition, and pharmacology.

Integrated component identification, network pharmacology, and experimental verification revealed mechanism of Dendrobium officinale Kimura et Migo against lung cancer

BACKGROUND

Dendrobium officinale Kimura et Migo (DO), a valuable Chinese herbal medicine, has been reported to exhibit potential effects in the prevention and treatment of lung cancer. However, its material basis and mechanism of action have not been comprehensively analyzed.

PURPOSE

The objective of this study was to preliminarily elucidate the active components and pharmacological mechanisms of DO in treating lung cancer, according to UPLC-Q/TOF-MS, HPAEC-PAD, network pharmacology, molecular docking, and experimental verification.

METHODS

The chemical components of DO were identified via UPLC-Q/TOF-MS, while the monosaccharide composition of Dendrobium officinale polysaccharide (DOP) was determined by HPAEC-PAD. The prospective active constituents of DO as well as their respective targets were predicted in the combined database of Swiss ADME and Swiss Target Prediction. Relevant disease targets for lung cancer were searched in OMIM, TTD, and Genecards databases. Further, the active compounds and potential core targets of DO against lung cancer were found by the C-T-D network and the PPI network, respectively. The core targets were then subjected to enrichment analysis in the Metascape database. The main active compounds were molecularly docked to the core targets and visualized. Finally, the viability of A549 cells and the relative quantity of associated proteins within the major signaling pathway were detected.

RESULTS

249 ingredients were identified from DO, including 39 flavonoids, 39 bibenzyls, 50 organic acids, 8 phenanthrenes, 27 phenylpropanoids, 17 alkaloids, 17 amino acids and their derivatives, 7 monosaccharides, and 45 others. Here, 50 main active compounds with high degree values were attained through the C-T-D network, mainly consisting of bibenzyls and monosaccharides. Based on the PPI network analysis, 10 core targets were further predicted, including HSP90AA1, SRC, ESR1, CREBBP, MAPK3, AKT1, PIK3R1, PIK3CA, HIF1A, and HDAC1. The results of the enrichment analysis and molecular docking indicated a close association between the therapeutic mechanism of DO and the PI3K-Akt signaling pathway. It was confirmed that the bibenzyl extract and erianin could inhibit the multiplication of A549 cells in vitro. Furthermore, erianin was found to down-regulate the relative expressions of p-AKT and p-PI3K proteins within the PI3K-Akt signaling pathway.

CONCLUSIONS

This study predicted that DO could treat lung cancer through various components, multiple targets, and diverse pathways. Bibenzyls from DO might exert anti-lung cancer activity by inhibiting cancer cell proliferation and modulating the PI3K-Akt signaling pathway. A fundamental reference for further studies and clinical therapy was given by the above data.

Functional properties, structural characteristics, and anti-complementary activities of two degraded polysaccharides from strawberry fruits

Two low-molecular-weight polysaccharides (DPSP50 and DPSP70) were obtained using hydrogen peroxide-vitamin C (H2O2-Vc) treatment at 50 °C and 70 °C, respectively. Both DPSP50 and DPSP70 comprised the same six monosaccharides in different ratios, and their molecular weights (Mws) were 640 kDa and 346 kDa, respectively. Functional properties analyses demonstrated that DPSP50 and DPSP70 each had an excellent water holding capacity, oil absorption capacity, and emulsion properties, as well as shear-thinning characteristics and viscoelastic properties. Fourier transform infrared (FT-IR) and nuclear magnetic resonance (NMR) spectroscopic assays confirmed the existence of α-, β-pyranose rings and the same six sugar residues in DPSP50 and DPSP70. The results of Congo red test, scanning electron microscopy (SEM), and X-ray diffraction (XRD) demonstrated that DPSP50 and DPSP70 did not contain triple-helix conformations, but were amorphous aggregates with flake-like shape and rough surface. Additionally, both DPSP50 and DPSP70 showed strong anti-complementary activities through the classical pathway and the alternative pathway. The results support the potential utility of these degraded polysaccharides from strawberry fruits in functional foods and medicines.

Structural characterization of Aspalatus linearis polysaccharide and its improving effect on acute alcoholic liver injury

Polysaccharides from natural sources can regulate the composition of intestinal flora through the "gut-liver axis" pathway, potentially ameliorating alcoholic liver injury. Aspalathus linearis, also known as rooibos, is one such natural product that has shown promise in this regard. This study looked at the structural properties of A. linearis polysaccharide (ALP) and how well it would work to treat acute alcoholic liver impairment. This study looks at the composition of monosaccharides, functional groups, and molecular weight (Mw) of a newly discovered water-soluble polysaccharide, named ALP. The polysaccharide is composed of pyranose rings, amide groups, and sulfate groups linked by β-glycosidic linkage. It has a relative Mw of 4.30 × 103 kDa and is composed of glucose, rhamnose, and some other monosaccharides. The study found that treating mice with the model of acute alcoholic liver disease with ALP could alleviate pathological symptoms, inhibit the release of inflammatory cytokines, and suppress indicators of oxidative stress. Experiments have shown that different doses of ALP can activate the P4502E1/Keap1-Nrf2-HO-1 signaling pathway. The regulation of inflammatory factors and downstream antioxidant enzymes occurs as a result. Based on these data, it is likely that ALP protects the liver via the "gut-liver axis" pathway by reducing oxidative stress-related damage, inflammation, and alcohol-related alterations to the gut microbiome. The results indicate that ALP mitigates injury caused by oxidative stress, inflammatory responses, and changes in the gut microbiota induced by alcohol through the "gut-liver axis" pathway, which provides protection to the liver. This provides preliminary evidence for the development of related drugs. PRACTICAL APPLICATION: Researchers extracted a polysaccharide from fresh leaves of Auricularia auricula. The polysaccharide was purified and determined to have a predominantly homogeneous molecular weight. An acute alcoholic liver damage mouse model was established, and it was concluded that the polysaccharide could ameliorate liver injury in mice through the "gut-liver axis" pathway. This novel polysaccharide can be used as an additive to develop functional foods with beneficial effects, which can positively impact the daily maintenance of consumers.

Structural characterization and potential anti-tumor activity of a polysaccharide from the halophyte Salicornia bigelovii Torr

Plant polysaccharides are highly potent bioactive molecules. Clarifying the structural composition and bioactivities of plant polysaccharides will provide insights into their structure-activity relationships. Therefore, herein, we identified a polysaccharide produced by Salicornia bigelovii Torr. and analyzed the structure and anti-tumor activity of its component, SabPS-1. SabPS-1 was 3.24 × 104 Da, primarily composed of arabinose (24.96 %), galactose (30.39 %), and galacturonic acid (23.20 %), rhamnose (6.21 %), xylose (4.99 %), glucuronic acid (3.12 %), mannuronic acid (1.75 %), mannose (1.69 %), glucose (1.54 %), fucose (1.12 %), and guluronic acid (1.03 %). The backbone of SabPS-1 was a → 4)-β-D-GalpA-(1→, →5)-α-L-Araf-(1→, and→4)-β-D-Galp-(1 → molecule with a branched chain of α-L-Araf-(1 → connected to sugar residues of →3,6)-β-D-Galp-(1 → in the O-3 position. SabPS-1 induced apoptosis and inhibited the growth of HepG-2 cells, with viability of 47.90 ± 4.14 (400 μg/mL), indicating anti-tumor activity. Apoptosis induced by SabPS-1 may be associated with the differential regulation of caspase 3, caspase 8, Bax, and Bcl-2. To the best of our knowledge, this is the first study to investigate the principal structures and anti-tumor biological activities of SabPS-1. Our findings demonstrated the excellent anti-tumor properties of SabPS-1, which will aid in the development of anti-tumor drugs utilizing Salicornia bigelovii Torr.

Recent advances in modifications of exudate gums: Functional properties and applications

Gums are high-molecular-weight compounds with hydrophobic or hydrophilic characteristics, which are mainly comprised of complex carbohydrates called polysaccharides, often associated with proteins and minerals. Various innovative modification techniques are utilized, including ultrasound-assisted and microwave-assisted techniques, enzymatic alterations, electrospinning, irradiation, and amalgamation process. These methods advance the process, reducing processing times and energy consumption while maintaining the quality of the modified gums. Enzymes like xanthan lyases, xanthanase, and cellulase can selectively modify exudate gums, altering their structure to enhance their properties. This precise enzymatic approach allows for the use of exudate gums for specific applications. Exudate gums have been employed in nanotechnology applications through techniques like electrospinning. This enables the production of nanoparticles and nanofibers with improved properties, making them suitable for the drug delivery system, tissue engineering, active and intelligient food packaging. The resulting modified exudate gums exhibit improved rheological, emulsifying, gelling, and other functional properties, which expand their potential applications. This paper discusses novel applications of these modified gums in the pharmaceutical, food, and industrial sectors. The ever-evolving field presents diverse opportunities for sustainable innovation across these sectors.

The chromosome-level genome and functional database accelerate research about biosynthesis of secondary metabolites in Rosa roxburghii

Rosa roxburghii Tratt, a valuable plant in China with long history, is famous for its fruit. It possesses various secondary metabolites, such as L-ascorbic acid (vitamin C), alkaloids and poly saccharides, which make it a high nutritional and medicinal value. Here we characterized the chromosome-level genome sequence of R. roxburghii, comprising seven pseudo-chromosomes with a total size of 531 Mb and a heterozygosity of 0.25%. We also annotated 45,226 coding gene loci after masking repeat elements. Orthologs for 90.1% of the Complete Single-Copy BUSCOs were found in the R. roxburghii annotation. By aligning with protein sequences from public platform, we annotated 85.89% genes from R. roxburghii. Comparative genomic analysis revealed that R. roxburghii diverged from Rosa chinensis approximately 5.58 to 13.17 million years ago, and no whole-genome duplication event occurred after the divergence from eudicots. To fully utilize this genomic resource, we constructed a genomic database RroFGD with various analysis tools. Otherwise, 69 enzyme genes involved in L-ascorbate biosynthesis were identified and a key enzyme in the biosynthesis of vitamin C, GDH (L-Gal-1-dehydrogenase), is used as an example to introduce the functions of the database. This genome and database will facilitate the future investigations into gene function and molecular breeding in R. roxburghii.

Polysaccharide from Boletus aereus ameliorates DSS-induced colitis in mice by regulating the MANF/MUC2 signaling and gut microbiota

Inflammatory bowel diseases (IBD) are chronic inflammatory conditions characterized by disruptions in the colonic mucus barrier and gut microbiota. In this study, a novel soluble polysaccharide obtained from Boletus aereus (BAP) through water extraction was examined for its structure. The protective effects of BAP on colitis were investigated using a DSS-induced mice model. BAP was found to promote the expression of intestinal mucosal and tight junction proteins, restore the compromised mucus barrier, and suppress the activation of inflammatory signaling. Moreover, BAP reshape the gut microbiota and had a positive impact on the composition of the gut microbiota by reducing inflammation-related microbes. Additionally, BAP decreased cytokine levels through the MANF-BATF2 signaling pathway. Correlation analysis revealed that MANF was negatively correlated with the DAI and the level of cytokines. Furthermore, the depletion of gut microbiota using antibiotic partially inhabited the effect of BAP on the activation of MANF and Muc2, indicating the role of gut microbiota in its protective effect against colitis. In conclusion, BAP had an obvious activation on MANF under gut inflammation. This provides new insights into the prospective use of BAP as a functional food to enhance intestinal health.

Golgi-localized APYRASE 1 is critical for Arabidopsis growth by affecting cell wall integrity under boron deficiency

Many nucleoside triphosphate-diphosphohydrolases (NTPDases/APYRASEs, APYs) play a key role in modulating extracellular nucleotide levels. However, the Golgi-localized APYs, which help control glycosylation, have rarely been studied. Here, we identified AtAPY1, a gene encoding an NTPDase in the Golgi apparatus, which is required for cell wall integrity and plant growth under boron (B) limited availability. Loss of function in AtAPY1 hindered cell elongation and division in root tips while increasing the number of cortical cell layers, leading to swelling of the root tip and abundant root hairs under low B stress. Further, expression pattern analysis revealed that B deficiency significantly induced AtAPY1, especially in the root meristem and stele. Fluorescent-labeled AtAPY1-GFP localized to the Golgi stack. Biochemical analysis showed that AtAPY1 exhibited a preference of UDP and GDP hydrolysis activities. Consequently, the loss of function in AtAPY1 might disturb the homoeostasis of NMP-driven NDP-sugar transport, which was closely related to the synthesis of cell wall polysaccharides. Further, cell wall-composition analysis showed that pectin content increased and borate-dimerized RG-II decreased in apy1 mutants, along with a decrease in cellulose content. Eventually, altered polysaccharide characteristics presumably cause growth defects in apy1 mutants under B deficiency. Altogether, these data strongly support a novel role for AtAPY1 in mediating responses to low B availability by regulating cell wall integrity.

Hypoglycemic Activity of Rice Resistant-Starch Metabolites: A Mechanistic Network Pharmacology and In Vitro Approach

Rice (Oryza sativa L.) is one of the primary sources of energy and nutrients needed by the body, and rice resistant starch (RRS) has been found to have hypoglycemic effects. However, its biological activity and specific mechanisms still need to be further elucidated. In the present study, 52 RRS differential metabolites were obtained from mouse liver, rat serum, canine feces, and human urine, and 246 potential targets were identified through a literature review and database analysis. A total of 151 common targets were identified by intersecting them with the targets of type 2 diabetes mellitus (T2DM). After network pharmacology analysis, 11 core metabolites were identified, including linolenic acid, chenodeoxycholic acid, ursodeoxycholic acid, deoxycholic acid, lithocholic acid, lithocholylglycine, glycoursodeoxycholic acid, phenylalanine, norepinephrine, cholic acid, and L-glutamic acid, and 16 core targets were identified, including MAPK3, MAPK1, EGFR, ESR1, PRKCA, FYN, LCK, DLG4, ITGB1, IL6, PTPN11, RARA, NR3C1, PTPN6, PPARA, and ITGAV. The core pathways included the neuroactive ligand-receptor interaction, cancer, and arachidonic acid metabolism pathways. The molecular docking results showed that bile acids such as glycoursodeoxycholic acid, chenodeoxycholic acid, ursodeoxycholic acid, lithocholic acid, deoxycholic acid, and cholic acid exhibited strong docking effects with EGFR, ITGAV, ITGB1, MAPK3, NR3C1, α-glucosidase, and α-amylase. In vitro hypoglycemic experiments further suggested that bile acids showed significant inhibitory effects on α-glucosidase and α-amylase, with CDCA and UDCA having the most prominent inhibitory effect. In summary, this study reveals a possible hypoglycemic pathway of RRS metabolites and provides new research perspectives to further explore the therapeutic mechanism of bile acids in T2DM.

Isolation, structural properties and bioactivities of polysaccharides from Crataegus pinnatifida

ETHNOPHARMACOLOGIC RELEVANCE

Crataegus pinnatifida, commonly known as hawthorn, is a plant species with a long history of medicinal use in traditional Chinese medicine. Hawthorn polysaccharides (HP) have gained worldwide attention due to their decent biological activities and potential health benefits. Their excellent antioxidant activity, antitumor activity, immunomodulatory activity, hypoglycemic effect and hypolipidemic effects, intestinal microbiota modulatory activity makes them valuable in the field of ethnopharmacological research.

AIM OF THE STUDY

The purpose of the current review is to provide a systematic and comprehensive summary of the latest literatures and put forward the future perspectives on hawthorn polysaccharides in the context of its extraction, purification, structural characteristics and bioactivities. Furthermore, the underlying structure-bioactivity relationship of hawthorn polysaccharides was also explored and discussed. The current review would provide the important research underpinnings and the update the information for future development and application of hawthorn polysaccharides in the pharmaceutical and functional food industries.

MATERIALS AND METHODS

We use Google Scholar, CNKI, PubMed, Springer, Elsevier, Wiley, Web of Science and other online databases to search and obtain the literature on extraction, isolation, structural analysis and the biological activity of hawthorn polysaccharides published before October 2023. The key words are "extraction", "isolation and purification", "bioactivities", and "Crataegus pinnatifida polysaccharides ".

RESULTS

Crataegus pinnatifida has been widely used for the treatment of cardiovascular diseases, digestive disorders, inflammatory and oxidative stress in traditional Chinese medicine. Polysaccharides are the key active components of Crataegus pinnatifida which have gained widespread attention. The structure and bioactivity of polysaccharides from Crataegus pinnatifida varies in terms of raw materials, extraction methods and purification techniques. Crataegus pinnatifida polysaccharides possess diverse bioactivities, including antitumor, immunomodulatory, hypoglycemic activity, cardioprotective and antioxidant activities, among others. These biological properties can not only lay firm foundation for the treatment of diverse diseases, but also provide a theoretical basis for the in-depth study of the structure-activity relationship. In addition, the underlying structure-activity relationship is also explored and discussed, and further research and development of hawthorn polysaccharides are also prospected.

CONCLUSION

As a natural compound, hawthorn polysaccharides has garnered significant attention and held immense research potential. Hawthorn polysaccharides can be obtained through different extraction methods, including hot water extraction method, ultrasonic extraction method and enzymatic extraction method etc. The structures of hawthorn polysaccharides have also been characterized and reported in numerous studies. Moreover, hawthorn polysaccharides exhibit a wide range of bioactivities, such as the antioxidant activity, the antitumor activity, the immunomodulatory activity, the hypoglycemic effect and the hypolipidemic effect, as well as the intestinal microbiota modulatory activity. These diverse bioactivities contribute to the growing interest in hawthorn polysaccharides and its potential applications. Hawthorn polysaccharides has promising application prospects in various industries, including functional food, pharmaceuticals and biomedical research. Therefore, it is imperative to fully explore and harness the potential of hawthorn polysaccharides in the food and medicine fields.

A comparison study on polysaccharides extracted from banana flower using different methods: Physicochemical characterization, and antioxidant and antihyperglycemic activities

This work investigated and compared the physicochemical characteristics, and antioxidant and antihyperglycemic properties in vitro of polysaccharides from a single banana flower variety (BFPs) extracted by different methods. BFPs extracted using hot water (HWE), acidic (CAE), alkaline (AAE), enzymatic (EAE), ultrasonic (UAE) and hot water-alkaline (HAE) methods showed different chemical composition, monosaccharide composition, molecular weight, chain conformation and surface morphology, but similar infrared spectra characteristic, main glycosidic residues, crystalline internal and thermal stability, suggesting that six methods have diverse impacts on the degradation of BFPs without changing the main structure. Then, among six BFPs, the stronger antioxidant activity in vitro was found in BFP extracted by HAE, which was attributed to its maximum uronic acid content (21.67 %) and phenolic content (0.73 %), and moderate molecular weight (158.48 kDa). The highest arabinose and guluronic acid contents (18.59 % and 1.31 % in molar ratios, respectively) and the lowest uronic acid content (14.30 %) in BFP extracted by HWE contributed to its better α-glucosidase inhibitory activity in vitro (66.55 %). The data offered theoretical evidence for choosing suitable extraction methods to acquire BFPs with targeted biological activities for applications, in which HAE and HWE could serve as beneficial methods for preparing antioxidant BFP and antihyperglycemic BFP, respectively.

Comparative Study on the Impact of Different Extraction Technologies on Structural Characteristics, Physicochemical Properties, and Biological Activities of Polysaccharides from Seedless Chestnut Rose (Rosa sterilis) Fruit

Seedless chestnut rose (Rosa sterilis S. D. Shi, RS) is a fresh type of R. roxburghii Tratt with copious functional components in its fruit. Polysaccharides are recognized as one of the vital bioactive compounds in RS fruits, but their antioxidant and hypoglycemic properties have not been extensively explored. Hence, in this study, accelerated solvent extraction (RSP-W), citric acid (RSP-C), 5% sodium hydroxide/0.05% sodium borohydride (RSP-A), and 0.9% sodium chloride (RSP-S) solution extraction were individually utilized to obtain RS fruit polysaccharides. The physicochemical properties, structural characteristics, and biological activities were then compared. Results indicated that extraction methods had significant influences on the extraction yield, uronic acid content, monosaccharide composition, molecular weight, particle size, thermal stability, triple-helical structure, and surface morphology of RSPs apart from the major linkage bands and crystalline characteristics. The bioactivity tests showed that the RSP-S, which had the greatest amount of uronic acid and a comparatively lower molecular weight, exhibited more potent antioxidant and α-glucosidase inhibitory property. Furthermore, all RSPs inhibited α-glucosidase through a mixed-type manner and quenched their fluorescence predominantly via a static quenching mechanism, with RSP-S showing the highest binding efficiency. Our findings provide a theoretical basis for utilizing RSPs as functional ingredients in food industries.

Structural characterization and immunomodulatory activity of a water-soluble polysaccharide from Poria cocos

In order to investigate the structural characteristics and immunomodulatory effects of Poria cocos polysaccharides, a water-soluble homogeneous polysaccharide (PCP-2) was isolated by water extraction and alcohol precipitation and further purified by Cellulose DEAE-52 and Sephacryl S-100HR column chromatography. PCP-2 is a heteropolysaccharide composed of glucose, galactose, mannose, and fucose in a molar ratio of 42.0: 35.0: 13.9: 9.1. It exhibits a narrow molecular weight distribution at 2.35 kDa with a branching degree of 37.1 %. The main chain types of PCP-2 include 1,3-β-D-Glc and 1,6-β-D-Glc as the backbone glucans and 1,6-α-D-Gal as the backbone heterogalactan. In vitro experiments demonstrate that PCP-2 directly stimulate RAW264.7 cell proliferation and secretion of inflammatory factors such as NO and TNF-α. In cyclophosphamide (CTX)-induced mice, it promotes the development of thymus and spleen immune organs, elevates the blood levels of IgG, IgA, IgM and CD3+CD4+ T cells, increases the intestinal villus height/ crypt depth ratio and improves gut barrier dysfunctions. These findings suggest that PCP-2 is a natural fungal polysaccharide with broad spectrum of immunoenhancing effects, which can significantly ameliorate the immunocompromised state.

Gut microbiota modulation, prebiotic and bioactive characteristics of date pomace polysaccharides extracted by microwave-assisted deep eutectic solvent

This study investigated the characteristics of polysaccharides from date pomace using microwave-assisted deep eutectic solvents. The impact on the gut microbiota and probiotics growth was examined in vitro. The study also examined its antioxidant properties, ability to inhibit enzymes linked to diabetes and high blood pressure, impact on cell growth, and physical properties. The isolated MPS had an average molecular weight of 8073.38 kDa and contained mannose, galacturonic acid, galactose, glucose, and fructose in specific proportions. At a concentration of 1000 mg/L, MPS showed strong antioxidant activity, with significant scavenging rates in various tests such as DPPH (57.0 ± 1.05 %) and ABTS (66.4 ± 2.48 %). MPS displayed 77 %, 80 %, and 43 % inhibition for α-amylase, α-glucosidase, and ACE-inhibition, respectively. MPS displayed significant antiproliferative effects, achieving 100 % and 99 % inhibition against Caco-2 and MCF-7 cells at 2500 mg/L, respectively. MPS showed broad-spectrum antibacterial properties against both Gram-positive and Gram-negative foodborne bacteria. Gemmiger formicilis, Blautia species, Collinsella aerofaciens, and Bifidobacterium longum showed strong positive correlations, suggesting increased SCFA production. Network analysis indicated species correlations, with 86 % showing negative correlations with Escherichia and Enterococcus saccharolyticus. MPS was abundant in Firmicutes, Actinobacteria, and Proteobacteria phyla. Date pomace could serve as a dietary fiber source, promoting better health.

Effect of polysaccharide concentration on heat-induced Tremella fuciformis polysaccharide-soy protein isolation gels: Gel properties and interactions

The formation of a single soybean protein isolate (SPI) gel is limited by the processing conditions, and has the disadvantages of poor gel property, and it is usually necessary to add other biomacromolecules to improve its property. In this study, we investigated the effects of polysaccharide concentration on gel properties and interaction mechanisms of Tremella fuciformis polysaccharide (TFP)-SPI complexes. It was found that (1) the rheological properties, texture properties, water-holding properties, and thermal stability of TFP-SPI composite gels were improved with the addition of TFP (0.25-2.0 %, w/v) in a concentration-dependent manner; (2) hydrogen bond, the electrostatic interaction, hydrophobic interaction, and disulfide bond in the gel system increased with the increase of TFP concentration; (3) the electrostatic and hydrophobic interactions played an important role in the formation of the TFP-SPI composite gel while hydrogen bond formation was the least contributor to the binary composite gel network. Overall, TFP is not only a critical health food but also a promising structural component for improving the gel properties of SPI.

Structural characterization of a polysaccharide derived from Saposhnikovia divaricatee (Turcz.) Schischk with anti-allergic and antioxidant activities

ETHNOPHARMACOLOGICAL RELEVANCE

Saposhnikoviae Radix, the dry root of Saposhnikovia divaricatee (Turcz.) Schischk, is a traditional chinese medicine used for the treatment of cold, headache, and skin pruritus.

AIM OF THE STUDY

This study aimed to identify novel active polysaccharides from Saposhnikovia divaricatee (Turcz.) Schischk and clarify their structures and bioactivities.

MATERIALS AND METHODS

The structure of polysaccharides was clarified by PMP-HPLC, methylation analysis, particle acid hydrolysis analysis and NMR analysis. The anti-allergic and antioxidant activities of polysaccharides were evaluated on allergic reaction model in RBL-2H3 cells and oxidative damage model of C. elegans.

RESULTS

We purified a novel homogenous polysaccharide named SP-3 from Saposhnikovia divaricatee (Turcz.) Schischk and its molecular weight was determined as 3.096 × 104 Da. Monosaccharide composition analysis revealed that SP-3 was composed of mannose, rhamnose, galacturonic acid, glucose, galactose, and arabinose (1.85: 5.22: 38.06: 2.36: 23.25: 29.26). The main linkage type of SP-3 was a repeat unit of →4,6)-β-D-Galp-(1 → 4)-α-D-GalpA-(1 → . The branches of SP-3 contained T-linked-α-L-Araf and 1,3,4-linked-α-L-Rhap. It was observed that SP-3 inhibited β-HEX release and inflammatory factors in RBL-2H3 cells subject to IgE stimulant. Meanwhile, SP-3 increased the mean lifespan of Caenorhabditis elegans under oxidative stress, reduced ROS content and increased antioxidant enzyme activities of C. elegans, potentially through activating the SOD-3.

CONCLUSIONS

A novel homogenous polysaccharide was identified from Saposhnikovia divaricatee (Turcz.) Schischk, and this polysaccharide SP-3 played key roles for the anti-allergic and antioxidant activities.

Ultrasound-assisted enzymatic extraction, structural characterization, and anticancer activity of polysaccharides from Rosa roxburghii Tratt fruit

In this work, Rosa roxburghii Tratt fruit polysaccharides (RPs) were extracted by ultrasound-assisted enzymatic method. The highest extraction yield of RPs was 4.78 ± 0.10 % under the optimal extraction conditions. Two purified fractions named RP1 and RP3 were obtained and systematically characterized by a combination strategy of FT-IR, monosaccharide composition, molecular weight distribution, methylation and 2D NMR spectroscopy analyses. Structural analysis showed that the main chain of RP1 was composed of rhamnogalacturonan type I (RG-I), while the side chains were rich in arabinogalactan and galactose. RP3 was composed of long homogalacturonan (HG) backbone interspersed with alternating sequences of RG-I domains, with galactose and arabinose side chains. RP1 and RP3 induced apoptosis of MCF-7 cells in a dose dependent manner in vitro especially for RP1, and had no effect on L929 cells. Furthermore, the possible anticancer mechanisms were revealed, and results suggested that RP1 induced apoptosis through ROS-dependent pathway and mitochondrial pathway. The results of this work not only provided an efficient extraction method and theoretical basis for the application of RPs, but also may contribute to develop novel functional foods or pharmaceutical products for the prevention and treatment of human breast cancer disease.

Structural elucidation of an active polysaccharide from Radix Puerariae lobatae and its protection against acute alcoholic liver disease

Radix Pueraria lobata can be used as medicine and food, whose polysaccharide is one of the main bioactive ingredients. To explore the effect and mechanism of Pueraria lobata polysaccharide, a homogeneous and novel water-soluble polysaccharide (PLP1) was successfully isolated and purified from P. lobata by column chromatography in the current study. Structure analysis revealed that PLP1 (Mw = 10.43 kDa) was constituted of the residues including (1 → 4)-α-d-glucose and (1 → 4, 6)-α-d-glucose, which were linked together at a ratio of 5:1 and represented the main glycosidic units. In vitro experiments indicated that PLP1 exhibited a better free radical-scavenging ability than amylose and amylopectin, meanwhile in vivo experiments indicated that PLP1 effectively protected against liver injury in mice with acute ALD through significantly inhibiting oxidative stress to regulate lipid metabolism, increasing short-chain fatty acid production, and maintaining intestinal homeostasis by regulating intestinal flora. Taken together, our results illustrate that PLP1 can regulate intestinal microecology as a feasible therapeutic agent for protecting against ALD on the ground of the gut-liver axis, thus laying a theoretical foundation for the rational exploitation and utilization of P. lobata resources in the clinic.

Effect of H2O2-assisted ultrasonic bath on the degradation and physicochemical properties of pectin

The effects of H2O2-assisted ultrasonic bath degradation technology on pectin were investigated. The degradation efficiency with different pectin concentrations, H2O2 concentrations, ultrasonic power, and ultrasonic time was analyzed. The results showed that pectin concentration was negatively correlated with the degradation efficiency of pectin, while, H2O2 concentration, ultrasonic power, and ultrasonic time were positive correlated with the degradation efficiency. Besides, the apparent viscosity and viscoelasticity of the degraded pectin decreased significantly. The antioxidant activity increased after the H2O2-assisted ultrasonic bath treatment. The results of FTIR, NMR, laser particle size, SEM, XRD, and AFM analysis indicated that the degradation treatment did not destroy the main structure of pectin. The average particle size and crystallinity of pectin decreased. The degree of aggregation and the height of the molecular chain decreased significantly. In conclusion, the H2O2-assisted ultrasonic bath degradation technique could effectively degrade pectin. This study provided a comprehensive analysis of the degradation of pectin under H2O2-assisted ultrasonic bath, which will be beneficial to further develop H2O2-assisted ultrasonic bath techniques for pectin degradation.

Physicochemical, rheological, antioxidant and immunological properties of four novel non-inulin (poly)saccharides from Asparagus cochinchinensis

The impacts of four extraction techniques, including hot water, ultrasonic-assisted, complex enzyme-assisted and acid-assisted methods, on the morphological, physicochemical properties and bioactivities of Asparagus cochinchinensis (poly)saccharides (EACP, WACP, UACP, and AACP) were investigated and compared. The four samples were mainly composed of glucose, fructose, and galactose with molar ratios of 50.8:22.7:4.4 for WACP, 53.9:26.0:5.3 for UACP, 35.6:14.1:21.4 for AACP and 45.0:15.6:9.0 for EACP, respectively. The rheological result showed that ACPs were non-Newtonian fluids. EACP with high purity (97.65 %) had good DPPH, O2- and ABTS+ radical scavenging activities, and significantly promoted the proliferation of the RAW264.7 cells at low concentration. UACP had good Fe2+ chelating ability, radical (DPPH, O2- and OH) scavenging activities, which might be attributed to the existence of triple-helix structure. AACP had high yield, molecular weight (17,477.2 Da), high crystallinity (23.33 %), and good radical (OH and ABTS+) scavenging activities. All four significantly stimulated the transcript expression levels of TNF-α, IL-1β and IL-6, as determined by RT-PCR. These results suggest that the exploitation and utilization of non-inulin (poly)saccharides extracted by ultrasonic-assisted, complex enzyme-assisted and acid-assisted extraction methods are potentially valuable as effective and natural immune adjuvants and antioxidants.

Beneficial medicinal effects and material applications of rose

Rose is a beautiful and fragrant plant with a variety of medicinal and substance uses. Various parts of rose such as fruits, flowers, leaves, and bark can be used in various product development, including cosmetics, food, pharmaceuticals, and engineering. The medical benefits of roses include the treatment of inflammation, diabetes, dysmenorrhea, depression, stress, seizures, and aging. Rose water is precious beauty water for skin care and has antibacterial effects on various microbiota. The surface of a rose petal exhibits a hierarchical structure comprising microscale papillae, with each papilla further featuring intricate nanofolds. With this structural feature, rose petals have high water contact angles together with antagonistic wetting properties. The hierarchical structures of rose petals were shown to have anti-reflection and light-harvesting abilities, which have the potential to be materials for various electronic products. Rose petals are an excellent biomimetic/bioinspired material that can be applied to the popular material graphene. This paper reviews the medical function and material application of roses. During the COVID-19 pandemic, medical materials or food shortages have become a global issue. Natural biomaterials could be a good alternative. Roses, with so many benefits, definitely deserve more exploration and promotion.

Hepatoprotective effects of peach gum polysaccharides against alcoholic liver injury: moderation of oxidative stress and promotion of lipid metabolism

Natural polysaccharides extracted from plants have received increasing attention due to their rich bioactivity. In our study, peach gum polysaccharides (PGPs) were extracted by water extraction-alcohol precipitation method. PGPs are typical pyranose polysaccharides with a mean molecular weight of 3.68 × 106 g/mol. The antioxidant activity and hepatoprotective capacity of PGPs were studied. In vitro, assays showed that PGPs scavenged DPPH, OH, and O2- in a dose-dependent manner. PGPs exhibited antioxidative properties against alcohol-induced HL7702 cells, as evidenced by the normalization of MDA, SOD, ROS, and GSH levels. To further elucidate the hepatoprotective mechanism of PGPs, we carried out in vivo experiments in male mice. PGPs exerted hepatoprotective effects in alcohol liver disease (ALD) mice by exerting antioxidant effects, decreasing the inflammatory response and modulating lipid metabolism. In addition, metabolomic analysis indicated that PGPs mainly regulate D-glutamine and D-glutamate metabolism, alanine, aspartate and glutamate metabolism, and arginine biosynthesis to promote hepatic metabolism and maintain body functions. Overall, this study revealed that the hepatoprotective mechanism of PGPs against ALD might be associated with the regulation of oxidative stress and lipid metabolism.

Enrichment of linoleic acid from yellow horn seed oil through low temperature crystallization followed by urea complexation method and hypoglycemic activities

Yellow horn (Xanthoceras sorbifolia Bunge) contained abundant linoleic acid (LA), accounting for about 44% of its lipid. Here, LA was enriched by low temperature crystallization followed by urea complexation, and the optimal enrichment conditions were optimized with response surface methods (3:1 ratio of EtOH/FFA, crystallization at - 25 °C for 24.5 h; 2:1 ratio of urea/FFA1, 6.6:1 ratio of EtOH/urea, crystallization at - 10 °C for 22.4 h). Under these conditions, the final LA content and recovery were 97.10% and 62.09%, respectively. In vitro hypoglycemic studies suggested that the LA extract with stronger inhibition on α-glucosidase and lower one on α-amylase than acarbose exhibited a positive control for carbohydrate digestion with lower adverse effects. The enzyme kinetics and Lineweaver-Burk plots analyses revealed a reversible competitive inhibition on α-amylase and α-glucosidase. The findings of this research provided insights for the development of the LA extract as the functional component of health food.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10068-023-01327-9.

Fine structure and hypoglycemic effect of a galactoglucan from the bulbs of Lanzhou lily

The present research aimed to further identify the fine structure, morphology, and thermal behaviors of a galactoglucan BHP-2 derived from Lanzhou lily bulbs through partial acid hydrolysis, methylation, 2D NMR (1H1H COSY, HSQC, and HMBC), scanning electron microscopy (SEM) and thermogravimetric-differential thermal analysis (TG-DTA). Additionally, the study assessed the potential in vitro hypoglycemic effect of BHP-2 by examining its inhibitory effect on α-glucosidase and α-amylase. The results indicated that the main backbone composition of BHP-2 consisted of →4)-α-D-Glcp-(1→, →3)-β-D-Glcp-(1 → and →6)-β-D-Galp-(1→, while the side chain composition predominantly featured →4)-α-D-Glcp-(1→, →3,5)-α-L-Araf-(1 → and →3)-β-D-Galp-(1→, attached to the C-2 and/or C-3 positions of →4)-α-D-Glcp-(1→. Terminal residues consisted of α-D-Glcp-(1 → and β-L-Araf-(1→. BHP-2 exhibited excellent thermal stability, with a microscopic surface characterized by tightly packed sheets and numerous spiral depressions, which might contribute to its remarkable in vitro hypoglycemic effect. BHP-2 showed competitive inhibition of α-amylase and mixed non-competitive inhibition of α-glucosidase, with respective IC50 values of 0.31 and 0.18 mg/mL, closely resembling to those of acarbose (0.27 and 0.12 mg/mL). These findings suggested that BHP-2 had potential as an additive for glycemic intervention.

Extraction of Ampelopsis japonica polysaccharides using p-toluenesulfonic acid assisted n-butanol three-phase partitioning: Physicochemical, rheological characterization and antioxidant activity

Polysaccharides as the biopolymers are showing various structural and modulatory functions. Effective separation of carbohydrate structures is essential to understanding their function. In this study, we choose an efficient organic acid in combination with recyclable organic solvent three-phase partitioning technology for the simultaneous extraction of polysaccharides from Ampelopsis japonica (AJPs) to ensure the integrity of linear and branched polysaccharide. The monosaccharide composition, glycosidic linkage information, structural and physicochemical analyses and associations with antioxidant activities were extensively analyzed. Synergistic extraction was compared with the conventional hot water extraction method and the results showed that AJPs-HNP exhibited better elastic properties and excellent antioxidant activity. Correlation analysis confirmed that the antioxidant activity of AJPs was significantly correlated with relative molecular weight, uronic acid content and terminal glycoside linkage molar ratios. The collaborative processing has significantly improved the utilization potential of AJPs and provides a sound theoretical foundation for the effective extraction and separation of polysaccharides. Overall, this work provides systematic and comprehensive scientific information on the physicochemical, rheological and antioxidant properties of AJPs, revealing their potential as natural antioxidants in the functional food and pharmaceutical industries.

Physicochemical properties and solution conformation of polysaccharides from Toona sinensis (A. Juss) Roem leaves

In this study, two polysaccharide fractions (TSP-1 and TSP-2) were isolated from Toona sinensis leaves. The physicochemical properties and solution conformations of TSP-1 and TSP-2 were investigated. DSC and TG results showed that TSP-1 and TSP-2 had thermal stability. The intrinsic viscosities of TSP-1 and TSP-2 solutions were 11.42 and 6.13 mL/g, respectively. Rheological results showed that the viscosities of TSP-1 and TSP-2 solutions were affected by polysaccharide concentration, Ca2+ and extreme pH. Furthermore, TSP-1 exhibited a weak gel behavior at the concentrations of 0.5 %-2.0 %, while TSP-2 showed a weak gel behavior at the concentration of 2 %. HPSEC-MALLS analysis revealed that the Rg values of TSP-1 and TSP-2 were 96.8 nm and 56.2 nm, respectively. Conformation analysis indicated that TSP-1 behaved as a sphere, while TSP-2 behaved like a rigid rod. These results suggest that TSP-1 and TSP-2 can be used as additives in food, pharmaceutical and cosmetic industries.

Mechanism for gel formation of pectin from mealy and crisp lotus rhizome induced by Na+ and D-glucono-d-lactone

Lotus rhizome residue, a cell wall material produced during the production of lotus rhizome starch, has long been underutilized. This study aims to extract pectin-rich polysaccharides from the cell wall of lotus rhizome and investigate their gelation mechanism in order to improve their industrial applicability. The results indicated that both CP and MP (pectin extracted from crisp and mealy lotus rhizome) exhibited a highly linear low methoxyl pectin structure, with the primary linkage mode being →4)-GalpA-(1→. The pectin chains in MP were found to be more flexible than those in CP. Then the impact of Na+, D-glucono-d-lactone (GDL), urea, sodium dodecyl sulfate (SDS), either individually or in combination, on the rheological characteristics of gels was evaluated. The results indicated that gels induced by GDL exhibited favorable thermoreversible properties, whereas the thermoreversibility of Na+-induced gels is poor. In addition to hydrogen bonding and ionic interactions, hydrophobic interactions also play a significant role in the formation of pectin gels. This study offers theoretical guidance and methodologies to improve the utilization rate of lotus rhizome starch processing by-products, while also provides novel insights into the correlation between LMP structure and gelation mechanism.

Distinctions in structure, rheology, antioxidation, and α-glucosidase inhibitory activity of β-glucans from different species

To investigate the distinctions between β-glucans from different species, Lentinula edodes β-glucan (LG), yeast β-glucan (YG), and oat β-glucan (OG) were extracted with hot water and determined as β-d-glucopyranose form by HPLC and FT-IR analysis. The molecular weight (Mw) of LG, YG, and OG was 670 kDa, 341 kDa, and 66 kDa, respectively. Scanning electron microscopy exhibited different micro surfaces of three β-glucans and the relative crystallinity of YG was the highest (29.8 %), followed by that of LG (23.2 %) and OG (20.3 %) determined by X-ray diffraction. Congo red analysis and atomic force microscopy showed that LG and YG have triple helical structures. The apparent viscosity, storage modulus (G'), and loss modulus (G") of β-glucans were increased with the increase of Mw. DPPH·, ABTS+·, HO·, and reducing power assays showed that β-glucans from different species exhibited different antioxidant activities, and the DPPH· scavenging rate of 2 mg/mL LG reached >80 % higher than that of YG and OG. The α-glucosidase inhibitory activity of OG was better than YG and LG. In summary, β-glucans from different species have different structures, physicochemical properties, and physiological functions, which provides theoretical evidence for the precise processing and utilization of β-glucan.

Effect of in vitro digestion and fermentation of kiwifruit pomace polysaccharides on structural characteristics and human gut microbiota

Kiwifruit pomace is abundant in polysaccharides that exhibit diverse biological activities and prebiotic potential. This study delves into the digestive behavior and fermentation characteristics of kiwifruit pomace polysaccharides (KFP) through an in vitro simulated saliva-gastrointestinal digestion and fecal fermentation. The results reveal that following simulated digestion of KFP, its molecular weight reduced by 4.7%, and the reducing sugar (CR) increased by 9.5%. However, the monosaccharide composition and Fourier transform infrared spectroscopy characteristics showed no significant changes, suggesting that KFP remained undigested. Furthermore, even after saliva-gastrointestinal digestion, KFP retained in vitro hypolipidemic and hypoglycemic activities. Subsequently, fecal fermentation significantly altered the physicochemical properties of indigestible KFP (KFPI), particularly leading to an 89.71% reduction in CR. This indicates that gut microbiota could decompose KFPI and metabolize it into SCFAs. Moreover, after 48 h of KFPI fecal fermentation, it was observed that KFPI contributed to maintaining the balance of gut microbiota by promoting the proliferation of beneficial bacteria like Bacteroides, Lactobacillus, and Bifidobacterium, while inhibiting the unfavorable bacteria like Bilophila. In summary, this study offers a comprehensive exploration of in vitro digestion and fecal fermentation characteristics of KFP, providing valuable insights for potential development of KFP as a prebiotic for promoting intestinal health.

The metabolism of nonstructural carbohydrates, lipids, and energy in two Cycas species with differential tolerance to unexpected freezing stress

Introduction

With the climate warming, the occurrence of freezing events is projected to increase in late spring and early autumn in the Northern Hemisphere. Observation of morphological traits showed that Cycas panzhihuaensis was more tolerant to unexpected freezing stress than C. bifida. Energy balance is crucial for plant tolerance to stress. Here, we aimed to determine whether the different responses of the two species to the unpredicted freezing stress were associated with the metabolism of energy and related substances.

Methods

The effects of unexpected freezing temperatures on C. panzhihuaensis and C. bifida were studied by measuring chlorophyll fluorescence parameters, energy charge and the profile of nonstructural carbohydrates (NSC) and lipids.

Results

C. panzhihuaensis exhibited higher stability of photosynthetic machinery than C. bifida under unpredicted freezing events. Significant interaction between species and treatments were observed in the energy charge, the level of NSC and its most components and the amount of most lipid categories and lipid classes. The decrease of soluble sugar and the increase of neutral glycerolipids at the early freezing stage, the accumulation of membrane glycerolipids at the late freezing stage and the continuous decrease of energy charge during the freezing period were the characteristics of C. panzhihuaensis responding to unexpected freezing stress. The degradation of membrane glycerolipids and the continuous decrease of soluble sugar during the freezing period and the accumulation of neutral glycerolipids and energy charge at the late freezing stage represented the characteristics of C. bifida responses.

Discussion

The different freezing sensitivity between C. panzhihuaensis and C. bifida might be associated with the differential patterns of the metabolism of energy, NSC and lipids. C. panzhihuaensis possesses the potential to be introduced to the areas of higher latitudes and altitudes.

Structural Characteristics and Multiple Bioactivities of Volvariella volvacea Polysaccharide Extracts: The Role of Extractive Solvents

The chemical structures and functional properties of plant-based polysaccharides are critically influenced by extractive solvents, but their roles are not clear. In this study, the structural characteristics and multiple bioactivities of Volvariella volvacea polysaccharides (VVPs) subjected to water (VVP-W), alkalis (sodium hydroxide, VVP-A), and acids (citric acid, VVP-C) as extractive solvents are investigated systematically. Of the above three polysaccharides, VVP-W exhibited the highest molecular weights, apparent viscosity, and viscoelastic properties. Functional analyses revealed that VVP-C had an excellent water-holding capacity, foaming properties, and emulsifying capacity, while VVP-A exhibited a promising oil-holding capacity. Moreover, VVP-C displayed strong inhibitory effects on α-amylase and α-glucosidase, which could be attributed to its content of total phenolics, proteins, and molecular weights. These findings have important implications for selecting the appropriate extraction techniques to obtain functional polysaccharides with targeted bioactive properties as food additives.

Optimization and Physicochemical Characterization of Polysaccharide Purified from Sonneratia caseolaris Mangrove Leaves: a Potential Antioxidant and Antibiofilm Agent

The Box-Behnken design was applied to determine the optimal parameters of the extraction condition by using the response surface methodology (RSM) from the leaves of Sonneratia caseolaris L. The result indicates the best-optimized conditions used for the extraction of polysaccharides at 84.02 °C temperature, 3.12 h time, and 27.31 mL/g for the water-to-material ratio. The maximum experimental yield of 8.81 ± 0.09% was obtained which is in agreement with the predicted value of 8.79%. Thereafter, low molecular weight polysaccharide (SCLP) was separated after sequentially being purified through column chromatography with a relative molecular weight of 3.74 kDa. The physicochemical properties were evaluated by characterization techniques such as FT-IR spectra, NMR spectrum, and SEM analysis. RP-HPLC analysis confirmed that SCLP was a heteropolysaccharide, majorly comprising rhamnose (28.25%), and xylose (27.17%) residues, followed by mannose (18.90%), and galactose (17.17%), respectively. Thermal analysis (TGA-DSC) results showed that SCLP is a highly thermostable polymer with a degradation temperature of 361.63 °C. X-ray diffraction patterns and tertiary structure analyses indicate that SCLP had a semi-crystalline polymer having a triple-helical configuration. Moreover, SCLP displayed potential antibiofilm ability for all the tested pathogens while stronger activity against Klebsiella pneumoniae and Pseudomonas aeruginosa. In addition, SCLP has potential in vitro antioxidant activity on DPPH, ABTS radical, superoxide, and Fe2+ chelating. These findings indicate that the polysaccharide has potentially been used in functional food, cosmetics, and pharmacological industries.

Physicochemical characterization, antioxidative and immunoregulatory activity of polysaccharides from the flower of Hylocereus undatus (Haw.) Britton et Rose

The flower of Hylocereus undatus (Haw.) Britton et Rose is widely recognized as a kind of medicine-food homologous resource due to its high nutritional value. However, there is a lack of in-depth studies on the purification, structure, antioxidative and immunoregulatory activities of polysaccharides from H. undatus flowers (FHRP). The objective of this study was to investigate the primary structure, antioxidative and immunoregulatory activities of the polysaccharides extracted from Hylocereus undatus flower using water extraction and chromatogram purification. Three polysaccharide fractions named FHRP-1, FHRP-2 and FHRP-3 were obtained. The results showed that FHRP-1, FHRP-2 and FHRP-3 (200-800 μg/mL) treatment for 24 h significantly increased the activities of superoxide dismutase (SOD) and catalase (CAT), and reduced the malondialdehyde (MDA) production in RAW 246.7 cells under H2O2-induced oxidative stress. Additionally, all three fractions exhibited immunoregulatory activities by enhancing the pinocytosis of RAW 264.7 cells and promoting the production of nitric oxide (NO), interleukin 6 (IL-6), and tumor necrosis factor α (TNF-α). Among three polysaccharide fractions, FHRP-3 exhibited the most promising antioxidative and immunoregulatory properties, which was attributed to its higher content of uronic acid, moderate molecular weight, and triple-helix conformation. These findings provide preliminary insights into the primary structural information and biological activities of FHRP.

Comparison on structure, properties and functions of pomegranate peel soluble dietary fiber extracted by different methods

In this research, the different methods (acid extraction, alkaline extraction and enzymatic extraction) were used to extract soluble dietary fiber (SDF) from pomegranate peel and compared with water extraction. Results revealed that all three extraction methods influenced the structure, physicochemical and functional properties of SDF. Especially, SDF extracted by enzymes (E-SDF) and SDF extracted by alkali (A-SDF) had higher yield (27.30% and 27.17%), molecular weight and thermal stability than SDF extracted by water (W-SDF). Higher oil holding capacity (OHC) was found in SDF extracted by acid (C-SDF) (3.18 g/g), A-SDF (3.18 g/g) and E-SDF (5.36 g/g) compared with W-SDF. In addition, A-SDF showed the smallest particle size, lowest ζ-potential and highest viscosity among the tested samples. E-SDF presented a more porous structure, better glucose adsorption capacity (GAC) and antioxidant activity than C-SDF and A-SDF. To sum up, A-SDF and E-SDF may have great potential to be functional food ingredients in the food industry.

Antioxidant Activities and Prebiotic Activities of Water-Soluble, Alkali-Soluble Polysaccharides Extracted from the Fruiting Bodies of the Fungus Hericium erinaceus

In this study, the digestion and fermentation properties of the bioactive water-soluble polysaccharide (HEP-W), and alkali-soluble polysaccharide (HEP-A) from Hericium erinaceus and the impact on the human colonic microbiota were determined using simulated saliva-gastrointestinal digestion and human fecal fermentation models in vitro. The basic physicochemical properties of HEP-W and HEP-A were determined at the same time. The results showed that the in vitro simulated digestion had almost no effect on the physicochemical properties of HEP-W and HEP-A, indicating that HEP-W and HEP-A were partially degraded. During fermentation, HEP-W and HEP-A increased the relative abundance of the dominant butyric acid-producing genera, the microbial community structure was significantly regulated, the gas production and short-chain fatty acid production in the fermentation broth were significantly increased, and the pH of the fermentation broth was reduced. There were structural and other differences in HEP-W and HEP-A due to different extraction methods, which resulted in different results. These results suggest that HEP-W and HEP-A may be potential gut microbial manipulators to promote gut health by promoting the production of beneficial metabolites by intestinal microorganisms using different butyric acid production pathways.

The role of fructose at a range of concentration on the texture and microstructure of freeze-dried pectin-cellulose matrix cryogel

Freeze-dried (FD) fruit and vegetable materials with a large amount of sugar are unstable. With the aim to understand the structure formation of FD products, the effects of fructose content on the texture and microstructure of FD matrix were investigated by using pectin-cellulose cryogel model. Cryogels containing fructose of 0-40% were produced using freeze-drying at three different primary drying temperatures of -40, -20, and 20°C. The resultant cryogels were characterized by texture profile analyzer, scanning electron microscope, and μCT. Results indicated that at drying temperature of -40°C, increasing fructose concentration promoted the hardness of the cryogels, and cryogels of 16% fructose obtained maximum hardness. Excessive fructose (≥20%) weakened the described hardness, while exhibiting stronger springiness and resilience. The microstructure showed that dense pores and increased wall thickness due to fructose aggregation were critical factors responsible for increased hardness. The porous structure as well as relatively large pore size were necessary for crispness, in addition, rigid pore wall with certain strength were also required. At the drying temperature of 20°C, large hetero-cavities dominated the microstructure of cryogels with 30% and 40% fructose, caused by melting inside during FD process. In this situation, lower Tm (-15.48 and -20.37°C) were responsible for cryogels' melting In conclusion, if possible, regulating fructose content and state may enable the precision texture design of FD fruit and vegetable foods.

Aggregation kinetics of green tea nanoparticles: Effects of pH, metal ions, and temperature

Colloidal nanoparticles in tea infusion are the link connecting micromolecular mechanism and macro-aggregation process of tea cream formation. In order to elucidate, the kinetics mechanism of green tea nanoparticles (gTNPs) aggregation, zeta-potentials, total average aggregation (TAA) rates, and critical coagulation concentration (CCC) in the presence of various pH and metal ions were investigated. Additionally, the effect of temperature on gTNPs aggregation was further explored. The results revealed that the TAA rate of gTNPs increased with decreasing pH values, the CCC of gTNPs increased in the order Mg2+  ≈ Ca2+  < Na+  ≈ K+ . The reason was that different positive ions changed the surface electric field strength of gTNPs to a different extent. Furthermore, it was indicated that low temperature could promote gTNPs aggregation in indirect way. Low temperature promoted the binding of epigallocatechin gallate (EGCG) and caffeine, and the combination between gTNPs and EGCG-caffeine complexes weakened the stability of gTNPs resulting from reduction in electrostatic repulsion. PRACTICAL APPLICATION: Tea is a popular beverage all over the world. This research revealed the mechanism of green tea nanoparticles aggregation and laid a theoretical foundation for the regulation of tea cream formation in tea beverage.

Proteomic analysis reveals that Polygonatum cyrtonema Hua polysaccharide ameliorates mice muscle atrophy in chemotherapy-induced cachexia

Polygonatum cyrtonema Hua polysaccharide (PCP) is the main bioactive compound derived from the herb Polygonati Rhizoma, known for its anti-fatigue, antioxidant, immunomodulatory, and anti-inflammatory properties. However, its effectiveness on alleviating chemotherapy-induced muscle atrophy has been unclear. In this study, we utilized proteomic analysis to investigate the effects and mechanisms of PCP on gemcitabine plus cisplatin (GC) induced muscle atrophy in mice. Quality control analysis revealed that the functional PCP, rich in glucose, is a heterogeneous polysaccharide comprised of nine monosaccharides. PCP (64 mg/kg) significantly alleviated body muscle, organ weight loss, and muscle fiber atrophy in chemotherapy-induced cachectic mice. Moreover, PCP suppressed the decrease in serum immunoglobulin levels and the increase in pro-inflammatory factor interleukin-6 (IL-6). Proteomic analysis demonstrated that PCP contributed to the homeostasis of protein metabolism in gastrocnemius muscle. Diacylglycerol kinase (DGKζ) and cathepsin L (CTSL) were identified as primary PCP targets. Furthermore, the IL-6/STAT3/CTSL and DGKζ/FoxO/Atrogin1 signaling pathways were validated. Our findings suggest that PCP exerts an anti-atrophy effect on chemotherapy-induced muscle atrophy by regulating the autophagy-lysosome and ubiquitin-proteasome systems.

Quality analysis and geographical origin identification of Rosa roxburghii Tratt from three regions based on Fourier transform infrared spectroscopy

The study aimed to provide new information of Rosa roxburghii Tratt (RRT) for the production of functional foods and distinguish the geographical origins of RRT. The nutritional components of RRT from three regions in China, such as vitamin C, polysaccharides, total flavonoids, and total phenolics, and their antioxidant activities were analyzed by one-way ANOVA. The results of Fourier transform infrared spectroscopy (FT-IR) combined with principal component analysis (PCA), stepwise linear discriminant analysis (SLDA), k-nearest neighbor (k-NN), and support vector machine (SVM) were used to establish discriminant models to identify the geographical origin of RRT. The results of one-way ANOVA showed that the contents of some nutrients and antioxidant activity were significantly different among RRT from different regions and their FT-IR spectra also showed significant differences. The characteristic fingerprint bands of FT-IR (1679-1618 cm^-1and 1520-900 cm^-1) closely related to the geographical origins of RRT were screened out. Based on SLDA, a discriminant model was established to realize the classification and identification of RRT from different regions and the correct discrimination rate of the testing sample set obtained with the established model reached 100 %. Geographical factors caused the obvious differences in nutritional components and antioxidant activity in RRT. The characteristic fingerprint bands of RRT obtained with FT-IR could be used to identify the geographical origins of RRT more quickly and accurately.

Structural characterization of polysaccharide fractions in areca (Areca catechu L.) inflorescence and study of its immunological enhancement activity in vitro and in vivo

To obtain the structure-function relationship of the polysaccharides derived from areca (Areca catechu L.) inflorescences in the aspect of its immunomodulatory ability, the plant-based polysaccharide was isolated and purified on column chromatography. The purity, primary structure and immune activity of four polysaccharide fractions (AFP, AFP1, AFP2 and AFP2a) were characterized comprehensively. The main chain of AFP2a was confirmed to be composed of → 3,6)-β-D-Galp-(1→, with branch chains linked to the O-3 position on the main chain. The immunomodulatory activity of the polysaccharides was evaluated using the RAW264.7 cells and immunosuppression mice model. It was observed that AFP2a enabled greater NO release (49.72 μmol/L) than other fractions, significantly promoted the phagocytic activity of macrophages, and improved splenocyte proliferation and T lymphocyte phenotype in mice. The present results may shine a light on a new research direction in immunoenhancers and provide a theoretical foundation for the development and application of areca inflorescence.

Selenium-enriched crude polysaccharide from Rosa roxburghii Tratt ameliorates cadmium-induced acute kidney injury in mice by modulating intestinal microorganisms

Cadmium is a toxic heavy metal that can cause serious damage to the body. It can trigger the oxidative stress response and damage various organs of the body (kidney, liver, brain, lung, testis, etc.). Selenium polysaccharides are considered to possess better antioxidant, immune regulation, and heavy metal removal activities than other polysaccharides, But few reports focused on Selenium Polysaccharides in Rosa roxburghii Tratt. The purpose of this study was to isolate crude polysaccharides (RRP), and crude Selenium polysaccharides (SeRRP) from Rosa roxburghii Tratt fruit and determine their structure, antioxidant activity, and protective effects on cadmium-exposed mice (PONY-2020-FL-62). Results showed that SeRRP had lower half-maximal inhibitory concentration (IC50) and higher superoxide dismutase (SOD) activity. The intake of food and body weight decreased, while the kidney index and liver index increased significantly after acute cadmium exposure. Most significantly, SeRRP ameliorates kidney injury by improving the kidney index. Furthermore, changes in the gut microbiota may be related to SeRRP or RRP. SeRRP and RRP decreased the Firmicutes/Bacteroidetes ratio, and increased the abundance of beneficial bacteria (Lachnospiraceae, Muribaculaceae, and Ruminococcaceae, etc.). These findings indicate that SeRRP and RRP have the potential to be functional food against oxidant and heavy metal exposure.

Effects of blackberry polysaccharide on the quality improvement of boiled chicken breast

Blackberry polysaccharide was isolated from blackberry powder with 70% ethanol. The crude polysaccharide was composed of 95.44% glucose, 2.01% arabinose, 1.81% galactose and 0.74% glucuronic acid. Chicken breast meat was only marinated with different concentrations of the isolated blackberry polysaccharide (1 g/kg, 3 g/kg) for 24 h at a ratio of material to liquid of 1:3, and boiled at 80℃ for 1 h. The differences in texture, water distribution and volatile flavor components among different groups （adding 0,1,3 g/kg blackberry polysaccharide) were investigated. The results showed that the addition of blackberry polysaccharide could significantly improve the hardness of chicken breast, the transformation of free water to bound water, the overall flavor characteristics of the control group and the addition of different concentrations of blackberry polysaccharide were significantly different, and the concentration of volatile flavor substances in boiled chicken breast was reduced.

Nanoparticles prepared by polysaccharides extracted from Biyang floral mushroom loaded with resveratrol: Characterization, bioactivity and release behavior under in vitro digestion

Resveratrol (RES) is a common active factor in the functional food field, but poor water solubility and low bioavailability have limited its application. In the present study, the novel nanoparticles (RES-CBFMP NPs) using floral mushroom polysaccharide as the wall material have been developed for delivering RES, aiming to overcome its application shortcomings. After ratio optimization, RES-CBFMP NPs (RES-CBFMP,1:8 w/w), which combined through the hydrogen bonds between RES and CBFMP, showed the best overall performance, with the encapsulation efficiency (EE) of 49.74 ± 0.16%, loading efficiency (LE) of 5.53 ± 0.02%, particle size of 158.56 ± 1.97 nm and zeta-potential of -17.56 ± 0.24 mV. In addition, RES-CBFMP NPs exhibited good physicochemical stabilities, sustained gastrointestinal digestive release property, as well as improved in vitro antioxidant and anticancer activities. This study may contribute to the development of RES oral delivery systems and the application of hydrophobic active molecules in the functional food field.

The physicochemical, antioxidant, hypoglycemic and prebiotic properties of γ-irradiated polysaccharides extracted from Lentinula edodes

In this study, the influence of γ-irradiation with different dose (0, 4, 8, and 16 kGy) on chemical composition, physicochemical features and bioactivities of polysaccharides extracted from Lentinula edodes (LEP) were investigated. The carbohydrate content (from 59.47 to 70.96%), the solubility, the ⋅OH and DPPH scavenging ability of LEP increased with the increased γ-irradiation dose, while the protein content, the weight-average and number-average molecular weight of LEP were significantly decreased with the increased γ-irradiation dose. Moreover, γ-irradiation treatment caused LEP color changes and surface topography destroyed. γ-Irradiated LEP showed higher hypoglycemic activities in vitro than that of non-irradiated LEP. Moreover, γ-irradiated LEP had better proliferation promoting effects on Lactobacillus rhamnosus and L. plantarum. These results showed that γ-irradiation treatment changes the physicochemical features of LEP, thus affects its antioxidant, hypoglycemic and prebiotic properties, which suggests that γ-irradiated LEP has potential application in the pharmaceutical industries and functional foods.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10068-022-01234-5.

Novel polysaccharide and polysaccharide-peptide conjugate from Rosa rugosa Thunb. pseudofruit - Structural characterisation and nutraceutical potential

A novel bioactive polysaccharopeptide (C1) and polysaccharide (C2) with an average molecular weight of 180 kDa and 70 kDa were isolated from R. rugosa pseudofruit. The composition of the macromolecules was established using ¹H NMR, FT-IR, GC-MS, SDS-PAGE coupled with enzymatic cleavage, and proteomic analyses (LC-MS). C1 was found to contain 60.56 ± 1.82 % of sugars and 21.17 ± 0.47 % of uronic acids. Its main neutral monosaccharides were arabinose, rhamnose, galactose, glucose, fucose, and mannose. C1 was found to be a polysaccharopeptide containing pectinesterase-like protein. C2 was composed of 32.85 ± 0.97 % of sugars and 48.77 ± 1.15 % of uronic acids. Its main neutral monosaccharides were galactose, glucose, rhamnose, arabinose, and mannose. A promising nutraceutical value of the polysaccharides was revealed. Assays showed strong α-glucosidase inhibitory activity of both macromolecules and considerable antiradical potential and moderate lipoxygenase inhibitory activity of the crude polysaccharide. Moreover, antiproliferative activity of C2 was observed.

Biosynthesis and physicochemical properties of low molecular weight gellan produced by a high-yield mutant of Sphingomonas paucimobilis ATCC 31461

Gellan gum (GG) is used in many industries. Here, we obtained a low molecular weight GG (L-GG) directly produced by M155, the high-yield mutant strain of Sphingomonas paucimobilis ATCC 31461, which was selected using UV-ARTP combined mutagenesis. The molecular weight of L-GG was 44.6 % lesser than that of the initial GG (I-GG), and the GG yield increased by 24 %. The monosaccharide composition and Fourier transform-infrared spectroscopic patterns of L-GG were similar to those of I-GG, which indicated that the decrease in the molecular weight of L-GG was probably because of reduction in the degree of polymerization. In addition, microstructural analysis revealed that the surface of L-GG was rougher, with smaller pores and tighter network, than that of I-GG. L-GG showed low hardness, gumminess, and chewiness, which are indicative of better taste. The results of rheological analysis revealed that the L-GG solution is a typical non-Newtonian fluid with low viscoelasticity, which exhibited stable dynamic viscoelasticity within 20-65 °C. To the best of our knowledge, this is the first report of direct biosynthesis of low molecular weight GG during fermentation, which will reduce the manufacturing costs. Our observations provide a reference for precise and expanded applications of GG.

Tremella fuciform Polysaccharides: Extraction, Physicochemical, and Emulsion Properties at Different pHs

The chemical composition, macromolecular characteristics, and structure of four types of Tremella fuciform polysaccharides (TPS) were analyzed, including one TPS that was extracted in the laboratory (L-TPS) and three commercial TPS. The effects of pH on the properties of TPS emulsions were investigated by analyzing their zeta potential, particle size, apparent viscosity, and stability. The results showed that L-TPS presented a higher percentage content of protein (2.33%) than commercial TPS (0.73–0.87%), and a lower molecular mass (17.54 × 106 g/mol). Thus, L-TPS exhibited the best emulsifying activity but gave poor emulsion stability. The droplet sizes and apparent viscosity of commercial TPS-stabilized emulsions were larger or higher in acidic environments. At pH 2, the apparent viscosity was the lowest for L-TPS. Commercial TPS emulsions were most stable at pH 6, while the L-TPS-stabilized emulsion was most stable at pH 2. The obtained results revealed that the emulsifying properties of TPS varied and the effects of pH on emulsion characteristics differed, as determined from the molecular mass, macromolecular characteristics, and structure. This research is useful for expanding the application of TPS as a novel food ingredient in emulsions.

Improved Extraction Yield, Water Solubility, and Antioxidant Activity of Lentinan from Lentinula edodes via Bacillus subtilis natto Fermentation

Lentinan has important applications in the food and medicine fields. Fermenting Lentinula edodes with Bacillus subtilis natto increased the lentinan extraction yield by 87.13% and greatly altered the molecular structure and antioxidant activity of lentinan. The uronic acid content in the lentinan molecular structure increased from 2.08% to 4.33%. The fermentation process did not affect the monosaccharide composition of lentinan, comprised of more than 90% glucose residues. Fermentation significantly reduced the molecular weight of lentinan and altered its apparent structure. The water solubility of fermented lentinan was increased by 165.07%, and the antioxidant activity was significantly improved. Fermentation using soybean as a substrate may be beneficial for enhancing the activity of Bacillus subtilis natto and producing lentinan with different molecular weights.