Characterization of physicochemical properties and antioxidant activity of polysaccharides from shoot residues of bamboo (Chimonobambusa quadrangularis): Effect of drying procedures

Physicochemical properties, structure and biological activity of ginger polysaccharide: Effect of microwave infrared dual-field coupled drying

Ginger was dried by microwave infrared dual-field coupled drying (MIDFCD). The composition, structure, physicochemical properties and biological activity of ginger polysaccharides at various stages of MIDFCD were investigated. The MIDFCD significantly impacted the chemical composition, molecular weight (Mw), microstructure, and physicochemical properties of ginger polysaccharides. However, there were no notable differences in functional group composition. The Mw and chemical composition were notably influenced by microwave-infrared exposure and prolonged drying time. The degradation of polysaccharides due to high temperatures in the later stage resulted in further decreases in Mw and alterations in monosaccharide composition. These changes in chemical composition and Mw affected thermal properties, crystallization properties, particle size, rheological properties, antioxidant capacity, and hypoglycemic activity. These findings suggest that MIDFCD enhances the quality and bioactivity of natural polysaccharides. This study offers theoretical support for MIDFCD processing and the value-added utilization of ginger.

Structural properties, bioactivities, structure-activity relationships and bio-applications of polysaccharides from Auricularia auricula: A review

Auricularia auricula (A. auricula), is a medicinal and edible fungus in China for thousands of years with rich nutrition and delicious taste. The main active ingredient of A. auricula is polysaccharide, which has antitumor, hypoglycemic, antioxidant, and immune regulation bioactivities. It is widely recognized that the biological activity of polysaccharides is closely related to the chemical structure and advanced structure. In terms of polysaccharides extracted from A. auricula (AAPs), there were distinguished structures reported due to the different original resources and extraction methods, leading to various bioactivities. However, the structure-activity relationship of AAPs has scarcely been reviewed till now. In addition, polysaccharides were found to have specific self-assembly properties recently, together with their bioactivities, endowing them with unique physicochemical properties. Nowadays, an increasing number of polysaccharides, such as cellulose, chitin, and pectin, have been used to construct various functional materials in the fields of food, cosmetics, and biomedical materials. Therefore, the construction of functional materials by AAPs is of great research significance. This article aims to provide a systematic review of the structure-activity relationship of AAPs and summarize the functional materials constructed based on AAPs to provide theoretical references for further research and application of AAPs.

Polysaccharides from Seedless Chestnut Rose (Rosa sterilis) Fruits: Insights into Innovative Drying Technologies and Their Structural Characteristics, Antioxidant, Antiglycation, and α-Glucosidase Inhibitory Activities

The selection of an optimal drying method is essential for extending the shelf life and enhancing the quality of Rosa sterilis fruits. This study investigated the effects of both innovative (microwave vacuum drying and infrared drying) and traditional (freeze-drying and hot air drying) techniques on the structural characteristics and bioactivities of polysaccharides from R. sterilis fruits (RSPs). Four different RSPs were obtained from fruits dried using these methods. Results demonstrated that the structural characteristics and bioactivities of RSPs varied significantly with the drying method. Notable differences were observed in extraction yield, total sugar, uronic acid content, monosaccharide molar ratios, molecular weight distribution, particle size, thermal stability, and microstructures of RSPs. Despite these variations, the types of constituent monosaccharides and major glycosidic linkages remained consistent across all methods. Notably, RSPs obtained via microwave vacuum drying (RSPs-MVD) showed a higher uronic acid content and lower molecular weight, and exhibited stronger in vitro antioxidant, α-glucosidase inhibitory, and antiglycation activities. These findings suggest that microwave vacuum drying is an effective pre-drying technique for extracting RSPs, making them suitable as bioactive ingredients in functional foods and pharmaceuticals for managing diabetes mellitus and its complications.

Effects of Different Drying Methods on the Structural Characteristics and Multiple Bioactivities of Rosa roxburghii Tratt Fruit Polysaccharides

Drying conditions significantly impact the compositions and microstructures of polysaccharides, leading to various effects on their chemical characteristics and bioactivities. The objective of this study was to investigate how different industrial drying techniques, i.e., hot air drying, infrared drying, microwave vacuum drying, and freeze drying, affect the structural properties and biological activities of polysaccharides extracted from Rosa roxburghii Tratt fruit (RRTP). Results revealed that these drying methods significantly altered the extraction yield, molecular weights, monosaccharide ratios, contents of uronic acid and total sugars, gelling properties, particle sizes, thermal stability, and microstructures of RRTPs. However, the monosaccharide composition and functional groups of polysaccharides remained consistent across the different drying techniques. Biological activity assays demonstrated that RRTPs, particularly those processed through microwave vacuum drying (MVD-RRTP), exhibited excellent anti-linoleic acid oxidation, robust anti-glycosylation effects, and significant α-glucosidase inhibition in vitro. The outcomes of this research demonstrate that microwave vacuum drying serves as an effective pre-extraction drying method for RRTPs, enhancing their biological activities. This technique is particularly advantageous for preparing RRTPs intended for use in functional foods and pharmaceuticals, optimizing their health-promoting properties for industrial applications.

Extraction, purification, structural characteristic, health benefit, and product application of the polysaccharides from bamboo shoot: A review

Bamboo shoot is a kind of widely distributed natural green vegetable, which has a long history of consumption and cultivation, and has edible, nutritional and economic value. Bamboo shoot is nutrient-rich food with carbohydrates, fats, proteins, polysaccharides, flavonoids, alkaloids and other chemical components, can meet the body's needs. Notably, bamboo shoot polysaccharides are the most attractive saccharides, most of which are water-soluble polysaccharides, and their various biological activities have been paid more attention by researchers. With the deepening of research on bamboo shoot polysaccharides, they have been found to have anti-diabetic, anti-oxidant, anti-inflammatory, anti-complement activities, immunomodulatory, etc. Further research on bamboo shoot polysaccharides, their sources, molecular weights, chemical structures, monosaccharide compositions and structural characteristics are constantly explored. In order to better research and development of bamboo shoot polysaccharides, it is necessary to carry on a comprehensive arrangement. Here, the extraction and purification methods, structural characteristics, health benefits, structure-activity relationships and product applications of bamboo shoot polysaccharides were systematically reviewed. This article will deepen the understanding of bamboo shoot polysaccharides, provide knowledge base for further research on bamboo shoot polysaccharides, and expand the vision for developing related products.

Nutritive profile, pharmaceutical potentials, and structural analysis of multifunctional bioactive fungal polysaccharides-A review

Asian nations have long used edible fungi as food and medicine. Polysaccharides are among the main building units of the cell walls of fungi. Fungal polysaccharides have been documented in the medicinal and industrial sectors as products with a vast array of various biological activities and applications such as antitumor, antioxidant, anticancer, immunomodulation, and antiviral activities, etc. The goal of this review is to give insights into the various biological activities of mushroom polysaccharides and their potential as a medicine for human health. The extraction, purity, and structural analysis of fungal polysaccharides were also reviewed in this work. Also, future prospective, and challenges for fungal polysaccharides in pharmaceutical applications can be found in this review. Overall, this review serves as a valuable resource in exploring the therapeutic potential and applications of fungal polysaccharides. By building upon the existing knowledge base and addressing critical research gaps, researchers can find new opportunities for utilizing fungal polysaccharides as valuable therapeutic agents and functional ingredients in pharmaceuticals, nutraceuticals, and biotechnology.

Isolation, purification, and biological activities of polysaccharides from Amorpha fruticosa flowers

The extraction, isolation, structural characterisation and biological activities of polysaccharides from Amorpha fruticosa flowers were investigated. First, the crude polysaccharide AFP was extracted, and two major purified polysaccharide fractions AFP-2 and AFP-3 were isolated. The molecular weight and monosaccharide compositions of AFP-2 and AFP-3 were determined. Then the antioxidant activities of AFP, AFP-2 and AFP-3 were assessed by DPPH radical, β-Carotene bleaching and hydroxyl radical assays. All three tested polysaccharides showed good antioxidant activity while AFP was the strongest one. The study also showed that AFP, AFP-2 and AFP-3 have good tyrosinase inhibition, moisture absorption and retention activities. The results will provide a helpful reference for the application of polysaccharide from Amorpha fruticosa flowers as a natural cosmetic ingredient.

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.

Medium composition optimization and characterization of polysaccharides extracted from Ganoderma boninense along with antioxidant activity

Ganoderma is a well-known medicinal macrofungal genus, of which several species have been thoroughly studied from the medicinal perspective, but most species are rarely involved in. In this study, we focus on the polysaccharides extracted from Ganoderma boninense and their antioxidant activity. Ganoderma boninense is a serious pathogen of oil palms that are cultivated commercially in Southeast Asia. Response surface methodology was conducted to optimize the liquid medium composition, and the mycelia biomass reached 7.063 g/L, that is, 1.4-fold compared with the seed medium. The crude and purified polysaccharides extracted from the fermentation broth showed well 1,1-diphenyl-2-picrylhydrazyl and 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid radical scavenging abilities, and the scavenging abilities of purified polysaccharides reached 94.47 % and 99.88 %, respectively. Six fractions of polysaccharides were extracted and purified from fruiting bodies, mycelia and fermentation broth separately with the elution buffers of distilled water and 0.1 M NaCl solution. Generally, the polysaccharides from fruiting bodies showed stronger protective effect on H2O2-induced HepG2 cell oxidative damage than other fractions. A total of five to seven monosaccharides were identified in the six fractions of polysaccharides. The correlation analysis revealed that the content of fucose was significantly correlated with the antioxidant activity of polysaccharides, while xylose showed negative correlation results. In summary, the polysaccharides from G. boninense have a potential to be used as natural antioxidants.

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.

Enzyme-assisted ultrasonic extraction of total flavonoids and extraction polysaccharides in residue from Abelmoschus manihot (L)

Abelmoschus manihot (L) is a traditional chinese herb and the present study focused on its comprehensive development and utilization. Enzyme-assisted ultrasonic extraction (EUAE) was investigated for the extraction and qualitative and quantitative analysis of flavonoids from Abelmoschus manihot (L) using a combination of ultra-performance liquid chromatography-photodiode array (UPLC-PDA), polysaccharides was extracted from residues and compared with directly extracted from raw materials. The optimal yield of 3.46±0.012 % (w/w) was obtained when the weight ratio of cellulase to pectinase was 1:1, the enzyme concentration was 3 %, the pH was 6.0, the solvent was a mixture of 70 % ethanol (v/v) and 0.1 mol/L NaH2PO4 buffer solution, the ultrasonic power was 500 W, the extraction time was 40 min, and the temperature of the extraction was 50 °C. The individual concentrations of interested flavonoids (rutin, neochlorogenic acid, nochlorogenic acid, lsoquercitrin, quercitrin, gossypin, quercetin) were effectively increased with the using of EUAE, compared with ultrasonic extraction (UE) method. Polysaccharides were extracted from each residue, respectively, the Polysaccharides yield in residue from EUAE was higher than that from UE, and closed to the yield from direct extraction in raw materials. The above results shown that the experimental process had the potential to be environmentall, friendly, straightforward and efficient.

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.

Recent advances in the influences of drying technologies on physicochemical properties and biological activities of plant polysaccharides

Plant polysaccharides, as significant functional macromolecules with diverse biological properties, are currently receiving increasing attention. Drying technologies play a pivotal role in the research, development, and application of various foods and plant polysaccharides. The chemical composition, structure, and function of extracted polysaccharides are significantly influenced by different drying technologies (e.g., microwave, infrared, and radio frequency) and conditions (e.g., temperature). This study discusses and compares the principles, advantages, disadvantages, and effects of different drying processes on the chemical composition as well as structural and biological properties of plant polysaccharides. In most plant-based raw materials, molecular degradation, molecular aggregation phenomena along with intermolecular interactions occurring within cell wall components and cell contents during drying represent primary mechanisms leading to variations in chemical composition and structures of polysaccharides. These differences further impact their biological properties. The biological properties of polysaccharides are determined by a combination of multiple relevant factors rather than a single factor alone. This review not only provides insights into selecting appropriate drying processes to obtaining highly bioactive plant polysaccharides but also offers a fundamental theoretical basis for the structure-function relationship of these compounds.

Effects of traditional and advanced drying techniques on the physicochemical properties of Lycium barbarum L. polysaccharides and the formation of Maillard reaction products in its dried berries

This study explored the effect of three different industrial drying methods on the physicochemical, nutritional, and safety profile of goji berries. The hot-air (HD) and microwave drying (MD) methods yielded berries with relatively high polysaccharide content, while vacuum freeze-drying (FD) yielded dried berries with better sensory qualities but relatively less polysaccharide content. The polysaccharides obtained from the HD and MD berries had lower molecular weight, high antioxidant activity and high degrees of Maillard reaction. Further investigations revealed that all three methods, in particular HD and MD, generated high levels of intermediate Maillard reaction products (55.8-86.3 mg/kg) and advanced glycation end-products (fluorescent intensity of 26784-51712), based on significant reduction of reducing sugar and amino acids in the HD and MD berries (p < 0.05). These findings highlight the need to scrutinize the effectiveness of traditional and emerging drying technologies used to produce safe fruits.

Extraction Optimization, Characterization and Biological Activities of Polysaccharide Extracts from Nymphaea hybrid

In this study, polysaccharide-rich Nymphaea hybrid extracts (NHE) were obtained using the ultrasound-assisted cellulase extraction (UCE) method optimized by response surface methodology (RSM). The structural properties and thermal stability of NHE were characterized by Fourier-transform infrared (FT-IR), high-performance liquid chromatography (HPLC) and thermogravimetry-derivative thermogravimetry (TG-DTG) analysis, respectively. Moreover, the bioactivities of NHE, including the antioxidant, anti-inflammatory, whitening and scratch healing activities were evaluated by different in vitro assays. NHE conveyed a good ability to scavenge against the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals and inhibit the hyaluronidase activity. NHE can effectively protect the HaCaT cells against oxidative damage by inhibiting the intracellular reactive oxygen species (ROS) production in the H₂O₂ stimulation assays and promoting the proliferation and migration in the scratch assays. In addition, NHE was proven to inhibit melanin production in B16 cells. Collectively, the above results seem to be the evidence needed to promote the potential of NHE to be regarded as a new functional raw material in the cosmetics or food industries.

Molecular Characterization and Bioactivities of a Novel Polysaccharide from Phyllostachys pracecox Bamboo Shoot Residues

Dietary carbohydrates are unexploited in the by-products of economically valuable Phyllostachys pracecox bamboo shoots. A residue-derived polysaccharide (PBSR1) was aqueously extracted from the processing waste of this bamboo shoot species. Its primary structure and advanced conformation were elucidated by a combined analysis of spectroscopy, chromatography, 2D nuclear magnetic resonance, laser light scattering and atomic microscopy. The results indicated PBSR1 was a triple-helix galactan consisting of →6)-β-D-Galp and →3)-β-D-Galp in linear with an 863 KD molecular weight (M_w). The relationship between the radius of gyration (Rg) and intrinsic viscosity ([η]) on M_w were established as R_g = 1.95 × 10^-2M_w^0.52±0.03 (nm) and [η] = 9.04 × 10^-1M_w^0.56±0.02 (mL/g) for PBSR1 in saline solution at 25 °C, which indicated it adopted a triple-helix chain shape with a height of 1.60 ± 0.12 nm supported by a red shift of λ_max in Congo red analysis. The thermodynamic test (TG) displayed that it had excellent thermal stability for the food industry. Further, those unique structure features furnish PBSR1 on antioxidation with EC₅₀ of 0.65 mg/mL on DPPH· and an ORAC value of 329.46 ± 12.1 μmol TE/g. It also possessed pronounced immunostimulation by up-regulating pro-inflammatory signals including NO, IL-6, TNF-α and IL-1β in murine cells. Our studies provided substantial data for the high-valued application of residues and a better understanding of the structure-function relationship of polysaccharide.

Characterization and Anti-Aging Activity of Polysaccharides from Akebia trifoliata Fruit Separated by an Aqueous Two-Phase System

Bioactive polysaccharides have numerous pharmacological effects that are beneficial to human health. Akebia trifoliata (Thunb.) Koidz. has great development prospects as a food resource with medicinal value. The polysaccharides (ATFP) were extracted from A. trifoliata fruit by an aqueous two-phase system. ATFP-3, purified with DEAE-52 and Sephadex G-200 from ATFP, was mainly composed of glucose (47.55%) and galactose (20.39%). Its hydroxyl radical scavenging rate was 89.30% at 1.60 mg/mL and its IC₅₀ was 0.29 mg/mL. ATFP-3 significantly enhanced the survival rate of Caenorhabditis elegans under thermal or oxidative stress. Furthermore, ATFP-3 could prolong the lifespan of C. elegans and improve the activities of the antioxidant enzyme, while also decrease the accumulation of lipofuscin and the level of malondialdehyde (MDA) in aging worms. Thus, ATFP-3 has application potential in health benefits for humans.

Sequential extraction, structural characterization, and antioxidant activity of polysaccharides from Dendrocalamus brandisii bamboo shoot shell

Polysaccharides including water-soluble fraction (W), 1,2-Cyclohexanediaminetetraacetic acid (CDTA)-soluble fraction (CA), sodium carbonate (Na₂CO₃)-soluble fraction (SC), 1 M potassium hydroxide (KOH)-soluble fractions (PH1), and 4 M KOH-soluble fraction (PH4) were successively extracted from Dendrocalamus brandisii bamboo shoot shells using water, CDTA, Na₂CO₃, and KOH solution. The analytical methods were employed to initially identify the structural characteristics of the five polysaccharide fractions, and their antioxidant capacities in vitro were determined. According to the data, the average molecular weight of the five polysaccharide fractions was between 4 816 and 993 935 Da. In all four types (CA, SC, PH1, and PH4), xylose was the most abundant monosaccharide, especially in PH1 and PH4. Both PH1 and PH4 were found to contain 1,4-β-d-Xylp as their main chain, as determined by nuclear magnetic resonance (NMR) spectroscopy. Additional research into CA and SC's antioxidant potential is required since they both showed potent in vitro antioxidant activities.

Physicochemical Properties and In Vivo Hepatoprotective Effect of Polysaccharides from Grape Pomace

Here, the polysaccharides from grape pomace, a by-product in the wine industry, were characterized and evaluated in vitro and in vivo. The polysaccharides were extracted and studied using spectroscopic and chemical methods. The results revealed that GPPs are rich in arabinose, galactose and glucuronic acid and are heteropolysaccharides without protein and nucleic acid, containing α-glycoside bonds with irregular clusters on the surface. In vitro antioxidant activity assays indicated that GPPs have concentration-dependent antioxidant activity. In vivo, GPPs markedly decreased the levels of TNF-a, IL-6, ALT, AST and MDA in serum and liver tissues and restored the levels of SOD, CAT and GSH. Additionally, further histopathological examination confirmed that GPPs could mitigate the injury of liver induced by CCl₄. Our results demonstrate that GPPs had antioxidant and hepatoprotective effects, and they are expected to be a potential ingredient for functional foods or hepatoprotective drugs.

Polysaccharides from steam-processed Polygonatum cyrtonema Hua protect against d-galactose-induced oxidative damage in mice by activation of Nrf2/HO-1 signaling

BACKGROUND

Polygonatum cyrtonema Hua is cultivated for its edible and medical value. The steam-processed rhizome of P. cyrtonema is the main form for daily consumption and it has been used traditionally in tonics for treating various age-related disorders. The aim of our study was to compare the physicochemical properties and antioxidant activity of polysaccharides respectively extracted from crude P. Cyrtonema (PCPC), and steam-processed P. cyrtonema (PCPS), and to explore a possible underlying antioxidant mechanism.

RESULTS

The PCPC with a molecular weight of 4.35 × 10³  Da mainly consisted of fructose and trace amounts of glucose, whereas PCPS with 4.24 × 10⁴  Da was composed of fructose, arabinose, glucose, xylose, mannose, galacturonic acid and glucuronic acid. The PCPC had a triple-helical conformation whereas PCPS was a random coil. Both exhibited free radicals- scavenging activity in vitro. In a mouse model of oxidative damage, PCPC or PCPS treatment significantly reversed histopathological alterations, reactive oxygen species (ROS) accumulation and the reduction of antioxidant enzyme activity. They both also promoted Nrf2 nuclear transport by decreasing Keap-1 expression and increasing HO-1 expression. Both in vitro and in vivo, PCPS exhibited more potent antioxidant activity than PCPC.

CONCLUSION

Overall, the results suggest that PCPS has a stronger effect on the prevention of oxidative damage by activating Nrf2/HO-1 antioxidant signaling. This study demonstrates the role of steam-processed P. cyrtonema rhizome and provides valuable perspective for PCPS as a functional agent. © 2022 Society of Chemical Industry.

Extraction, Characterization, and In Vitro Hypoglycemic Activity of a Neutral Polysaccharide from the New Medicinal Mushroom Cantharellus yunnanensis (Agaricomycetes)

Polysaccharides serve as promising ingredients for health-beneficial functional foods, while there were no investigations into the structural characterizations and bioactivities of an edible mushroom Cantharellus yunnanensis. In the study, crude polysaccharides from this mushroom were extracted by hot water and isolated by ethanol precipitation. Then, a neutral polysaccharide (named CY-1) was purified from the crude polysaccharide by deproteinization with Sevag reagent, decolorization with a kind of macroporous adsorption resin SP-825, DEAE-52 cellulose column chromatography and dialysis. The physicochemical properties of CY-1 were characterized by UV, IR, SEM, NMR, and HPLC analyses. Structural characterizations revealed that CY-1 is a homogeneous heteropolysaccharide with an average molecular weight of 3.06 × 104 Da. CY-1 exhibited a honeycomb structure with an irregular branching shape, and it was composed of mannose, glucose, fucose, xylose, arabinose, galactose, rhamnose, and glucuronic acid, with molar fractions of 54.83%, 25.11%, 10.28% 4.53%, 2.12%, 1.64%, 0.83%, and 0.64%, respectively. In vitro hypoglycemic tests showed that CY-1 had an inhibitory effect on α-glucosidase. In addition, CY-1 of 160 µg/mL promoted glucose consumption in normal HepG2 cells. These results suggested that CY-1 may be a potential hypoglycemic agent.

The effect of structure and preparation method on the bioactivity of polysaccharides from plants and fungi

Polysaccharides are not only the main components in the cell walls of plants and fungi, but also a structure that supports and protects cells. In the process of obtaining polysaccharides from raw materials containing cell walls, the polysaccharides on the cell walls are the products and also a factor that affects the extraction rate. Polysaccharides derived from plants and fungi have mild characteristics and exhibit various biological activities. The biological activity of polysaccharides is related to their chemical structure. This review summarizes the effects of the physicochemical properties and structure of polysaccharides, from cell walls in raw materials, that have an impact on their biological activities, including molecular weight, monosaccharide composition, chain structure, and uronic acid content. Also, the structure of certain natural polysaccharides limits their biological activity. Chemical modification and degradation of these structures can enhance the pharmacological properties of natural polysaccharides to a certain extent. At the same time, the processing method affects the structure and yield of polysaccharides on the cell wall and in the cell. The extraction and purification methods are summarized, and the effects of preparation methods on the structure and physiological effects of polysaccharides from plants and fungi are discussed.

The Effects of Drying Techniques on Phytochemical Contents and Biological Activities on Selected Bamboo Leaves

The therapeutic potential of bamboos has acquired global attention. Nonetheless, the biological activities of the plants are rarely considered due to limited available references in Sabah, Malaysia. Furthermore, the drying technique could significantly affect the retention and degradation of nutrients in bamboos. Consequently, the current study investigated five drying methods, namely, sun, shade, microwave, oven, and freeze-drying, of the leaves of six bamboo species, Bambusa multiplex, Bambusa tuldoides, Bambusa vulgaris, Dinochloa sublaevigata, Gigantochloa levis, and Schizostachyum brachycladum. The infused bamboo leaves extracts were analysed for their total phenolic content (TPC) and total flavonoid content (TFC). The antioxidant activities of the samples were determined via the 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and ferric reducing antioxidant power (FRAP) assays, whereas their toxicities were evaluated through the brine shrimp lethality assay (BSLA). The chemical constituents of the samples were determined using liquid chromatography−tandem mass spectrometry (LC-MS/MS). The freeze-drying method exhibited the highest phytochemical contents and antioxidant activity yield, excluding the B. vulgaris sample, in which the microwave-dried sample recorded the most antioxidant and phytochemical levels. The TPC and TFC results were within the 2.69 ± 0.01−12.59 ± 0.09 mg gallic acid equivalent (GAE)/g and 0.77 ± 0.01−2.12 ± 0.01 mg quercetin equivalent (QE)/g ranges, respectively. The DPPH and ABTS IC50 (half-maximal inhibitory concentration) were 2.92 ± 0.01−4.73 ± 0.02 and 1.89−0.01 to 3.47 ± 0.00 µg/mL, respectively, indicating high radical scavenging activities. The FRAP values differed significantly between the drying methods, within the 6.40 ± 0.12−36.65 ± 0.09 mg Trolox equivalent (TE)/g range. The phytochemical contents and antioxidant capacities exhibited a moderate correlation, revealing that the TPC and TFC were slightly responsible for the antioxidant activities. The toxicity assessment of the bamboo extracts in the current study demonstrated no toxicity against the BSLA based on the LC50 (lethal concentration 50) analysis at >1000 µg/mL. LC-MS analysis showed that alkaloid and pharmaceutical compounds influence antioxidant activities, as found in previous studies. The acquired information might aid in the development of bamboo leaves as functional food items, such as bamboo tea. They could also be investigated for their medicinal ingredients that can be used in the discovery of potential drugs.

Polysaccharides from Bamboo Shoot (Leleba oldhami Nakal) Byproducts Alleviate Antibiotic-Associated Diarrhea in Mice through Their Interactions with Gut Microbiota

A water-soluble polysaccharide BSP was extracted from the basal part of bamboo shoot, a main by-product of bamboo shoot processing. BSP is composed of glucose (72.8%), xylose (19.43%) and a small amount of galactose, arabinose, glucuronic acid and mannose. The effects of BSP on mice with antibiotic-associated diarrhea (AAD) were investigated. The mice fed with BSP exhibited significant higher bodyweight gain, lower pH value and higher concentrations of SCFAs in the feces compared with those fed with saline. BSP administration reduced the inflammatory cells in the small intestine and colon in the AAD mice, and Firmicutes/Bacteroidetes ratio in the gut was decreased from 0.56 to 0.19. Moreover, BSP administration affected the composition and diversity of the gut microbiota in the AAD mice, particularly on the improvement of beneficial bacteria such as Bacteroides, Lactobacillus and Lachnospiraceae_NK4A136_group. Our results suggest that the polysaccharides from bamboo shoot by-products could be an attractive natural component for gut health and AAD treatment.

Comparison on Bioactivities and Characteristics of Polysaccharides From Four Varieties of Gastrodia elata Blume

The composition, physicochemical properties, in vitro biological activity, and hypoglycemic activity exhibited by polysaccharides from four varieties of G. elata were investigated in this study; the four extracted GaE polysaccharides were termed as GaE-B (G. elata Bl. f. glauca S. chow polysaccharides), GaE-R (G. elata Bl. f. elata polysaccharides), GaE-Hyb (hybridization of G. elata Bl. f. glauca S. chow and G. elata Bl. f. elata polysaccharides), and GaE-G (G. elata Bl. f. viridis Makino polysaccharides). As revealed by the results, the GaE polysaccharides were found with the same monosaccharide composition, primarily including glucose, whereas the content of each variety was significantly different. In addition, different degrees of differences were found in the in vitro antioxidant and hypoglycemic activity, molecular weight, yield, and chemical composition exhibited by the abovementioned varieties. However, GaE-B and GaE-Hyb were found with similar physical properties, chemical composition, and antioxidant and hypoglycemic activity. GaE-R had the lowest yield, total sugar content, and molecular weight, whereas it involved higher xylose, binding protein, and polyphenols as well as higher antioxidant and hypoglycemic activity. In contrast, GaE-G was found with the highest yield, total sugar content, and molecular weight, whereas it contained the lowest xylose, binding protein, and polyphenols, as well as the weakest antioxidant and hypoglycemic activity. In brief, the polysaccharide of G. elata, a plant resource for homology of medicine and food, could more significantly enhance the biological activity of G. elata as it was released in the process of decocting and stewing. To be specific, the assessment of polysaccharide activity alone suggested that GaE-R was the best.

Investigation of the Structural, Thermal, and Physicochemical Properties of Nanocelluloses Extracted From Bamboo Shoot Processing Byproducts

Nanocellulose has gained increasing interest due to its excellent properties and great potential as a functional component or carrier in food and pharmaceutical industries. This study investigated the structural, thermal, and physicochemical properties of nanofibrillated cellulose (NFC) and nanocrystalline cellulose (CNC) extracted from bamboo shoot (Leleba oldhami Nakal) processing byproducts. NFCs were prepared through low concentration acid hydrolysis combined with ultrasonic treatment. CNCs were further isolated from NFCs using sulfuric acid hydrolysis treatment. TEM images showed that NFC and CNC exhibited typical long-chain and needle-like structures, respectively. CNC suspension was stable due to its zeta potential of -34.3 ± 1.23 mV. As expected, both NFC and CNC displayed high crystallinity indexes of 68.51 and 78.87%, and FTIR analysis confirmed the successful removal of lignin and hemicellulose during the treatments. However, the thermogravimetric analysis indicated that sulfuric acid hydrolysis decreased the thermal stability of CNCs. The improved physicochemical properties of NFC and CNC suggested their potential in various applications.

The complete chloroplast genome of critically endangered Chimonobambusa hirtinoda (Poaceae: Chimonobambusa) and phylogenetic analysis

Chimonobambusa hirtinoda, a threatened species, is only naturally distributed in Doupeng Mountain, Duyun, Guizhou, China. Next-generation sequencing (NGS) is used to obtain the complete chloroplast (cp) genome sequence of C. hirtinoda. The sequence was assembled and analyzed for phylogenetic and evolutionary studies. Additionally, we compared the cp genome of C. hirtinoda with previously published Chimonobambusa species. The cp genome of C. hirtinoda has a total length of 139, 561 bp and 38.90% GC content. This genome included a large single -copy (LSC) region of 83, 166 bp, a small single-copy (SSC) region of 20, 811 bp and a pair of inverted repeats of 21,792 bp each. We discovered 130 genes in the cp genome, including 85 protein-coding genes, 37 tRNA, and 8 rRNA genes. A total of 48 simple sequence repeats (SSRs) were detected. The A/U preference of the third nucleotide in the cp genome of C. hirtinoda was obtained by measuring the codon usage frequency of amino acids. Furthermore, phylogenetic analysis using complete cp sequences and matK gene revealed a genetic relationship within the Chimonobambusa genus. This study reported the chloroplast genome of the C. hirtinoda.

Ameliorating effects of water bamboo shoot (Zizania latifolia) on acute alcoholism in a mice model and its chemical composition

In this study, the ameliorative effect of water bamboo shoot (WBS) on acute alcoholism mice was investigated and potential biological compounds were explored. Results showed that extraction methods significantly affected the active substances contents and bioactivities of WBS. Principal component analysis (PCA) showed that alkali extract (NE) obtained the highest score, therefore, it was selected for further analysis. Animal experiments showed that NE demonstrated ameliorative effects on acute alcoholism mice as evident by significantly elevated activities of dehydrogenase (alcohol dehydrogenase, acetaldehyde dehydrogenase) and antioxidant enzymes (superoxide dismutase, glutathione peroxidase, catalase), whereas significantly reduced the levels of aminotransferase (alanine aminotransferase, aspartate aminotransferase) in serum. The potential bioactive activity compounds of NE were explored by UPLC-MS/MS and bioinformatics analysis. Butyl isobutyl phthalate vanillin, ferulic acid methyl ester might be the major compounds in NE on alleviating acute alcoholism. These results indicated that WBS possesses potential ameliorating effect on acute alcoholism.

Comparison of the chemical composition and antioxidant stress ability of polysaccharides from Auricularia auricula under different drying methods

Auricularia auricula fruiting body-derived polysaccharides (AAPs) were dried using different drying procedures, including hot air-, far infrared-, freeze-, and microwave-drying. The influences of different drying procedures on the chemical compositions and antioxidant activity in vitro and in vivo of AAPs were investigated. The results indicated that freeze-dried AAPs (AAPs-F) possessed the highest uronic acid content (33.53%) and the lowest molecular weight (406.77 kDa). Moreover, AAPs-F exhibited the most potent antioxidant abilities in vitro, including ABTS⁺ and DPPH˙ scavenging abilities, ferric reducing power, and metal ion chelating capacity. Besides, AAPs-F could significantly prolong the lifespan of wild-type C. elegans under oxidative stress induced by H₂O₂ and methyl viologen (p < 0.05) and upregulate the mRNA expression levels of daf-16 (>2.7 fold), sod-3 (>9.2 fold), skn-1 (>4.5 fold) and sir-2.1 (>1.9 fold), and play a significant role in protecting C. elegans against apoptosis (p < 0.05). Hence, freeze-drying was determined as the preferred procedure for obtaining high-quality AAPs.

Isolation, structures and bioactivities of the polysaccharides from Radix Hedysari: A review

Radix Hedysari, a well-known traditional Chinese herbal medicine, has a long history as a medicinal plant in China based on its wide spectrum of biological and pharmacological activities. Until now, many chemical constituents have been isolated and identified from Radix Hedysari, such as polysaccharides, flavonoids, phenylpropanoids, trace elements and so on. Of these, Radix Hedysari polysaccharides are one of the most important active compounds of the Radix Hedysari and have various biological activities, including anti-tumor activity, antioxidant activity, anti-diabetic activity, immunity enhancement effect and regulation of intestinal flora. These beneficial biological activities are related to the chemical structure of the Radix Hedysari polysaccharides. The chemical structure of HPS is the basis of its biological activity, which is affected by many factors, such as the composition of monosaccharide, the size of relative molecular weight, the way of glycoside bond connection, the three-dimensional structure of polysaccharide, and so on. Different extraction and separation methods lead to different configurations of polysaccharides and different biological activities of polysaccharides. In general, the bioactivity of polysaccharides showed a certain dose-response or structure-activity relationship. At present, few studies of regarding the structure-function relationships of these polysaccharides have been reported, and it is not easy to relate the structures of HPS to their biological activities. Nevertheless, some relationships can be inferred as follows. This article is aimed to provide a systematic and up-to-date review on the extraction, purification, structural characterization, and biological activities of the Radix Hedysari polysaccharides to support its further therapeutic potentials and sanitarian functions. Furthermore, the possible development and a perspective for future research of Radix Hedysari polysaccharides are also discussed.

Emerging drying techniques for food safety and quality: A review

The new trends in drying technology seek a promising alternative to synthetic preservatives to improve the shelf-life and storage stability of food products. On the other hand, the drying process can result in deformation and degradation of phytoconstituents due to their thermal sensitivity. The main purpose of this review is to give a general overview of common drying techniques with special attention to food industrial applications, focusing on recent advances to maintain the features of the active phytoconstituents and nutrients, and improve their release and storage stability. Furthermore, a drying technique that extends the shelf-life of food products by reducing trapped water, will negatively affect the spoilage of microorganisms and enzymes that are responsible for undesired chemical composition changes, but can protect beneficial microorganisms like probiotics. This paper also explores recent efficient improvements in drying technologies that produce high-quality and low-cost final products compared to conventional methods. However, despite the recent advances in drying technologies, hybrid drying (a combination of different drying techniques) and spray drying (drying with the help of encapsulation methods) are still promising techniques in food industries. In conclusion, spray drying encapsulation can improve the morphology and texture of dry materials, preserve natural components for a long time, and increase storage times (shelf-life). Optimizing a drying technique and using a suitable drying agent should also be a promising solution to preserve probiotic bacteria and antimicrobial compounds.

Natural Polysaccharides as Preventive and Therapeutic Horizon for Neurodegenerative Diseases

Neurodegenerative diseases are a serious and widespread global public health burden amongst aging populations. The total estimated worldwide global cost of dementia was US$818 billion in 2015 and has been projected to rise to 2 trillion US$ by 2030. While advances have been made to understand different neurodegenerative disease mechanisms, effective therapeutic strategies do not generally exist. Several drugs have been proposed in the last two decades for the treatment of different types of neurodegenerative diseases, with little therapeutic benefit, and often with severe adverse and side effects. Thus, the search for novel drugs with higher efficacy and fewer drawbacks is an ongoing challenge in the treatment of neurodegenerative disease. Several natural compounds including polysaccharides have demonstrated neuroprotective and even therapeutic effects. Natural polysaccharides are widely distributed in plants, animals, algae, bacterial and fungal species, and have received considerable attention for their wide-ranging bioactivity, including their antioxidant, anti-neuroinflammatory, anticholinesterase and anti-amyloidogenic effects. In this review, we summarize different mechanisms involved in neurodegenerative diseases and the neuroprotective effects of natural polysaccharides, highlighting their potential role in the prevention and therapy of neurodegenerative disease.

Changes of structures and biosynthesis/hydrolysis-associated genes expression of glucans at different Volvariella volvacea maturity stages

In the present study, effects of maturity stage on structural characteristics and biosynthesis/hydrolysis-associated genes expression of glucans from Volvariella volvacea fruit body were well investigated. Elongation and pileus expansion stages decreased total soluble carbohydrate and protein contents to 17.09 mg/g and 8.33 mg/g, and significantly accumulated the total amino acids contents to 32.37 mg/g. Yields of crude polysaccharides significantly increased to 8.12% at egg stage and decreased to 3.72% at pileus expansion stage. Purified VVP I-a and VVP I-b were proved to be α-glucans. The maturity process affected the monosaccharide compositions, decreased the molecular weights of VVP I-a and VVP I-b with decreased transcription levels of glucan biosynthesis-associated enzyme genes vvugp and vvgls and increased glucan hydrolysis-associated glucanase gene vvexg2 expression with no significant effects on backbone structures including glycosidic linkages and configurations. The findings would benefit for understanding change patterns of V. volvacea glucan structures and their biosynthesis/hydrolysis-associated genes expression at maturity stages.

Physicochemical, morpho-structural, and biological characterization of polysaccharides from three Polygonatum spp

Polygonatum species, including P. cyrtonema, P. kingianum, and P. sibiricum, are edible plants with medicinal purposes, which have long been consumed as food due to their high nutritional value. In this study, polysaccharides from P. cyrtonema (PCP), P. kingianum (PKP) and P. sibiricum (PSP) were obtained, and their physicochemical properties and in vitro biological activities were investigated. Our results demonstrated that PCP, PKP, and PSP consist of major fructose and minor glucose, galacturonic acid, and galactose in different molar ratios with the molecular weights of 8.5 × 10³ Da, 8.7 × 10³ Da, and 1.0 × 10⁴ Da, respectively. The three polysaccharides had triple-helical structures with β-d-Fruf, α-d-Glcp, α-d-Galp sugar residues, and an O-acetyl group, and displayed peak-shaped structures in different sizes. They also exhibited thermal, shear-thinning behavior and viscoelastic properties, and PCP presented the highest viscoelasticity. Moreover, they exerted strong free radical-scavenging abilities, and significant reducing capacity. PCP was the strongest, followed by PSP and then PKP. They significantly promoted the polarization of the M1 macrophage, with the effect of PCP ranking first. All three had similar effects on GLP-1 secretion. It is, therefore, necessary to identify the various roles of these three Polygonatum polysaccharides as functional agents based on their bioactivities and physicochemical properties.

Three Polygonatum polysaccharides with different physicochemical properties exert distinct effects on free radical-scavenging abilities and the promotion of M1 macrophage polarization, while they have similar effects on GLP-1 secretion.

Effect of steaming process on the structural characteristics and antioxidant activities of polysaccharides from Polygonatum sibiricum rhizomes

Polygonatum sibiricum (P. sibiricum) rhizomes are widely used as a tonic and functional food, and are often processed to enhance their tonic function by repeated steaming and drying. As the most important constituent, the polysaccharide from P. sibiricum rhizomes (PSP) has demonstrated various activities, but the alteration of structural characteristics and activities of the purified PSPs during steaming process was rarely investigated. To well understand the effect of steaming process on the polysaccharides of P. sibiricum, neutral polysaccharides from P. sibiricum rhizomes (PSP0 ~ PSP9) after steaming were first isolated and purified, and then the chemical properties and antioxidant activities were determined. The results showed that the molar ratios of monosaccharides in PSPs were different. The molecular weights of PSPs were increased significantly after the fourth steaming. Morphological studies showed that the surface of PSPs became much tighter during the steaming process. Fourier transform infrared spectroscopy spectra displayed the polysaccharides had similar backbones and chemical groups. Furthermore, the antioxidant activity of PSPs was measured through radical scavenging tests. It was found that the radical scavenging activity of PSPs was elevated strikingly after steaming, and increased gradually with numbers of steaming process. The biological and chemical variance of PSPs revealed considerable segregation of PSP0, PSP1 ~ PSP4 and PSP5 ~ PSP9. In conclusion, our results proposed the fourth time as the optimal number of steaming to extract functional polysaccharide from P. sibiricum rhizomes.

Effects of drying on the structural characteristics and antioxidant activities of polysaccharides from Stropharia rugosoannulata

We investigated the structural characteristics and antioxidant activities of two types of neutral polysaccharides and two types of acidic polysaccharides from Stropharia rugosoannulata under different drying methods. Fresh S. rugosoannulata were processed with freeze-vacuum drying (FVD) and hot-air drying (HAD). Polysaccharides from the dried S. rugosoannulata (SRP) were purified using a DEAE-52 cellulose column to obtain two types of neutral SRPs (FSRP-1 and HSRP-1) and two types of acidic SRPs (FSRP-2 and HSRP-2). We found that drying can affect the structural characteristics and antioxidant activities of SRPs. Varied monosaccharide compositions were found in FSRP-1, FSRP-2, HSRP-1 and HSRP-2, and HAD-treated SRP had more glucose and less galactose. The (1 → 6)-α-D-Galp linkage was the primary chain in FSRP-1 and HSRP-1, whereas the (1 → 3)-β-D-Glcp was the backbone structure in FSRP-2 and HSRP-2. Our results thus suggest that hot air drying changed the β-configuration in polysaccharides. FSRP-1, FSRP-2, HSRP-1 and HSRP-2 had positive ferric ion reducing antioxidant power and scavenging activities on ABTS+ and hydroxyl radicals, whereas HSRP exhibited a stronger antioxidant activity than that of FSRP. Hot-air dried S. rugosoannulata could therefore be recommended as a suitable candidate for use in the preparation of antioxidant polysaccharides as functional foods.

Comparison of free, conjugated, and insoluble-bound phenolics and their antioxidant activities in oven-drying and freeze-drying bamboo (Phyllostachys edulis) shoot tips

Bamboo(Phyllostachys edulis) shoot was reported to be rich in phenolics. In the present study, free phenolics, conjugated phenolics, and insoluble-bound phenolics of oven-drying and freeze-drying bamboo shoot tips were extracted and separated, of which total phenolic content (TPC), total flavonoid content (TFC), and their antioxidant activities were determined. Phenolics of different binding forms were qualitatively analyzed using HPLC-ESI-QqQ-MS. A total of 22, 41, and 28 compounds were confirmed or tentatively identified in free, conjugated, and insoluble-bound phenolic extraction, respectively. The majority of the identified compounds were organic acids and phenolic acids. Oven-drying samples exhibited higher TPC (10.53-24.92 mg GAE/100 g DW) and TFC (5.80-33.27 mg CE/100 g DW) values, and stronger antioxidant activities (DPPH, ABTS, and FRAP) than freeze-drying (TPC: 1.67-15.28 mg GAE/100 g DW, TFC: 1.43-29.05 mg CE/100 g DW). Insoluble-bound phenolics were the major contributor to the total antioxidant activity. The present study investigated the phenolics composition and antioxidant activities of different binding forms in bamboo shoot tip comprehensively, and provided available information for their high-value deep-processing.