Physicochemical properties and prebiotic activities of polysaccharides from longan pulp based on different extraction techniques

Tibetan kefir grains fermentation alters physicochemical properties and improves antioxidant activities of Lycium barbarum pulp polysaccharides

There is a lack of research on how Tibetan kefir grains fermentation alters the physicochemical properties and biological activity of Lycium barbarum pulp polysaccharides, despite some reports that fermentation can affect the structure and activity of plant polysaccharides. This study demonstrated that, through fermentation, the molecular weight of polysaccharides decreased from 25.33 to 15.11 kg/mol while the contents of total sugar and uronic acid increased by 19.11% and 40.38%, respectively. Furthermore, after fermentation, the polysaccharides exhibited an uneven and rough surface along with a reduced number of branched chains and triple helix structures. Tibetan kefir grains fermentation enhanced the antioxidant activity of polysaccharides, which may be attributed to an increase in arabinose, galactose, and uronic acid content and a decrease in polysaccharide molecular weight. This research offers an alternative viewpoint on the potential application of Tibetan kefir grains-fermented Lycium barbarum pulp polysaccharides in functional foods.

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.

Structural characterization and prebiotic activity of rhamnogalacturonan-I rich pumpkin pectic polysaccharide extracted by alkaline solution

The present study aimed to investigate the structural and physicochemical characteristics of alkali-extracted pectic polysaccharide (AkPP) and to evaluate its prebiotic effects. AkPP was obtained from pumpkin pulp using an alkaline extraction method. AkPP, which had a molecular weight (Mw) of mainly 13.67 kDa and an esterification degree of 9.60%, was composed mainly of galacturonic acid (GalA), rhamnose (Rha), galactose, and arabinose. The ratio of the homogalacturonan (HG) region to the rhamnogalacturonan-I (RG-I) region in AkPP was 48.74:43.62. In the nuclear magnetic resonance spectrum, the signals indicating α-1,4-linked D-GalA, α-1,2-linked L-Rha, α-1,2,4-linked L-Rha residues were well resolved, demonstrating the presence of the HG and RG-I regions in its molecular structure. Collectively, AkPP was low methoxyl pectin rich in the RG-I region with short side chains and had a low Mw. Thermal analysis revealed that AkPP had good thermal stability. Compared to inulin, AkPP more effectively promoted the proliferation of Lactobacillus acidophilus, Lacticaseibacillus rhamnosus GG, Lacticaseibacillus casei, and Lacticaseibacillus paracasei and the production of lactic, acetic, and propionic acids. This study presents the unique structural features of AkPP and provides a scientific basis for further investigation of the potential of AkPP as a promising prebiotic.

Comparative Study on the Mechanism of Macrophage Activation Induced by Polysaccharides from Fresh and Dried Longan

Longan (Dimcarpus longan Lour.) is a kind of traditional fruit used as a medicine and a food. Fresh longan is primarily consumed as a fruit, whereas dried longan is commonly employed for medicinal purposes. The differences in the immunomodulatory activities and mechanisms of polysaccharides between dried and fresh longan remain unclear. The present study comparatively analyzed the mechanisms of macrophage activation induced by polysaccharides from dried (LPG) and fresh longan (LPX). The results revealed that LPG and LPX differentially promoted macrophage phagocytosis and the secretion of NO, TNF-α, and IL-6. RNA-seq analysis revealed that LPG and LPX differentially affected gene expression in macrophages. The LPG treatment identified Tnf and chemokine-related genes as core genes, while myd88 and interferon-related genes were the core genes affected by LPX. A comprehensive analysis of the differentially expressed genes showed that LPG initiated macrophage activation primarily through the TLR2/4-mediated TRAM/TRAF6 and CLR-mediated Src/Raf1 NF-κB signaling pathways. LPX initiated macrophage activation predominantly via the CLR-mediated Bcl10/MALT1 and NLR-mediated Rip2/TAK1 MAPK and NF-κB signaling pathways. Interestingly, the non-classical NF-κB signaling pathway was activated by polysaccharides in both dried and fresh longan to elicit a slow, mild immune response. LPG tends to promote immune cell migration to engage in the immune response, while LPX facilitates antigen presentation to promote T cell activation. These findings contribute insights into the mechanisms underlying the differences in bioactivity between dried and fresh longan and their potential applications in immune-enhancing strategies and functional-food development.

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.

Potential of longan (Dimocarpus longan Lour.) in functional food: A review of molecular mechanism-directing health benefit properties

Longan (Dimocarpus longan Lour.) has received widespread attention worldwide as a therapeutic food with nutritional, economic, and medicinal value. Its fruit, seed, pericarp, and flower becoming dietary tools for health maintenance when it comes to targeting chronic diseases or sub-health conditions. In recent years, research focusing on longan and human health has intensified, and the high-value products of the whole fruit, including polyphenols, polysaccharides, angiotensin-I-converting enzyme (ACE)-inhibiting peptides, gamma-aminobutyric acid (GABA), and Maillard reaction products etc., may have beneficial effects on human health by preventing the onset of chronic diseases and cancer, maintaining intestinal homeostasis and skin health. Here, we review and summarize the new available evidence on the bioactive role of phytochemicals in longan and explore the relationship between longan bioactive compounds and health benefits, with a focus on the molecular mechanisms of the health effects.

Effect of hydrochloric acid and citric acid with ultrasound processing on characteristics of superfine-ground pectic polysaccharides from okra (Abelmoschus esculentus L.) peel

The structural properties and biological activities of okra pectic polysaccharides (OPs) were impacted by various extraction methods. Based on commonly grinding (40, 100 meshes) and superfine grinding okra powders, two extraction solvents (hydrochloric acid, HA; citric acid, CA) were used firstly. Next, the extraction yield, physical and chemical properties, molecular structure and functional properties of OPs were analyzed by non-ultrasonic treatment and ultrasound-assisted superfine grinding method. The outcomes demonstrated that the extraction yield of OPs rose as the particle size of the powder decreased. HA-OPs had higher molecular weight (Mw), apparent viscosity and emulsification ability than CA-OPs. CA-OPs had higher esterification degree (DE), solubility and total sugar content, and higher amounts of rhamnogalacturonan-I (RG-I) segments. Compared with OPs without ultrasound-assisted extraction, ultrasound-assisted superfine grinding extraction exhibited higher sugar content, antioxidant capacity, emulsification ability, lower Mw, DE and apparent viscosity. Finally, the correlation between structure and function of OPs was further quantified. The antioxidant capacity was positively correlated with RG-I content, and negatively correlated with DE and Mw. The emulsification ability was mainly positively correlated with the GlcA of OPs. This study provides a theoretical basis for the development of OPs foods with clear structure-function relationship, which would be instructive for the application of OPs in food and cosmetics.

Effects of different extraction methods on the physico-chemical characteristics and biological activities of polysaccharides from Clitocybe squamulosa

This study comparatively evaluated the effects of the commonly used six extraction methods (acidic, alkaline, enzymatic, ultrasonic, high-pressure, and microwave) on the physico-chemical properties, processing characteristics, and biological activities of polysaccharides from Clitocybe squamulosa (CSFPs). The results show that polysaccharides extracted using an enzyme-assisted extraction method has a relatively high extraction yield (4.46 ± 1.62 %) and carbohydrate content (70.79 ± 6.25 %) compared with others. Furthermore, CSFPs were all composed of glucose, galactose, mannose, xylose, and glucosamine hydrochloride. Only ultrasonic-assisted extraction of polysaccharides (CSFP-U) has a triple helix chain conformation. Scanning electron microscopy (SEM) revealed significant differences in the microstructure of polysaccharides prepared using different methods. Besides that, the polysaccharides prepared by alkali extraction (CSFP-B) and high-pressure assisted extraction (CSFP-H) have good water (2.86 ± 0.29 g/g and 3.15 ± 0.29 g/g) and oil (8.13 ± 0.32 g/g and 7.97 ± 0.04 g/g) holding properties. The rheological behavior demonstrated that CSFPs solutions were typical non-Newtonian fluid. Apart from this, the antioxidant capacity (clearing DPPH (IC50 = 0.29) and ABTS free radicals (IC50 = 0.19), total reduction ability (IC50 = 3.02)) of polysaccharides prepared by the microwave-assisted extraction (CSFP-M) method was significantly higher than that of other extraction methods. By contrast, the polysaccharide prepared by acid extraction (CSFP-A) has the optimum binding capacity (bile acid salt (71.30 ± 6.78 %) and cholesterol (57.07 ± 3.26 mg/g)). The antibacterial activity of CSFPs was positively correlated with their concentration. Thus, the research results can provide a theoretical basis for the development and utilization of polysaccharides from C. squamulosa.

Effect of monosaccharide composition and proportion on the bioactivity of polysaccharides: A review

Polysaccharides have been widely used in pharmaceutical and food industries due to their diverse bioactivity, high safety, and few or no side effects. However, inability to quickly produce, screen, and synthesize bioactive polysaccharides is the limiting factor for their development and application. Structural features determine and influence the bioactivity of polysaccharides. Among them, monosaccharide is the basic unit of polysaccharide, which not only affects electrification, functional group, and bioactivity of polysaccharide but also is one of the simplest polysaccharide indexes to be detected. At present, effects of monosaccharide composition and proportion on anti-inflammatory, antioxidant, antitumor, immunomodulatory, antibacterial, and prebiotic activities of polysaccharides are reviewed. Further problems need to be considered during regulation and analysis of monosaccharide composition and proportion of polysaccharides. Overall, present work will provide help and reference for production, development, and structure-function investigation of polysaccharides based on their monosaccharide.

Research progress in extraction, purification, structure of fruit and vegetable polysaccharides and their interaction with anthocyanins/starch

Fruits and vegetables contain polysaccharides, polyphenols, antioxidant enzymes, and various vitamins, etc. Fruits and vegetables polysaccharides (FVPs), as an important functional factor in health food, have various biological activities such as lowering blood sugar, blood lipids, blood pressure, inhibiting tumors, and delaying aging, etc. In addition, FVPs exhibit good physicochemical properties including low toxicity, biodegradability, biocompatibility. Increasing research has confirmed that FVPs could enhance the stability and biological activities of anthocyanins, affecting their bioavailability to improve food quality. Simultaneously, the addition of FVPs in natural starch suspension could improve the physicochemical properties of natural starch such as viscosity, gelling property, water binding capacity, and lotion stability. Hence, FVPs are widely used in the modification of natural anthocyanins/starch. A systematic review of the latest research progress and future development prospects of FVPs is very necessary to better understand them. This paper systematically reviews the latest progress in the extraction, purification, structure, and analysis techniques of FVPs. Moreover, the review also introduces the potential mechanisms, evaluation methods, and applications of the interaction between polysaccharides and anthocyanins/starch. The findings can provide important references for the further in-depth development and utilization of FVPs.

Structural and chemical insights into the prebiotic property of hemicellulosic polysaccharide from Santalum album L

Hemicellulose was extracted by alkali treatment of de-pectinated cell wall material of Santalum album L. (sandalwood) suspension culture cells. The physicochemical properties and prebiotic activities of a purified major fraction of Hemicellulose-B, termed as HB-I, were investigated. GC analysis of hydrolyzed and derivatized HB-I showed the presence of arabinose (~64 %), galactose (~16 %) and glucose (~16 %) as major monosaccharide units along with minor amount of rhamnose. Methylation and NMR studies on the purified polysaccharide revealed the presence of 6-β-d-Glcp, β-d-Galp, 3,5-α-l-Araf, α-l-Araf, 5-α-l-Araf, 2,3-α-l-Araf and, α-l-Rhap residues, from which a proposed structure of repeating units was established. The growth of probiotic Lactobacillus spp. strains L. acidophilus, L. casei, L. plantarum and L. rhamnosus was promoted while that of Escherichia coli was suppressed significantly in presence of HB-I. Our results highlight valorization of sandalwood biomass and explore the role of mixed α, β-linked heteroglycan as a potential prebiotic molecule thus indicating the possibility of development of low-cost bioprocesses for production of functional food ingredients.

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.

Bioengineered Wheat Arabinoxylan - Fostering Next-Generation Prebiotics Targeting Health-Related Gut Microbes

Dietary prebiotic fibers play an important role in modulating gut microbiota by enhancing the abundance of beneficial microorganisms and their bioactive metabolites. However, dietary fibers are a structurally heterogeneous class of polysaccharides, varying in molar mass, branching patterns, and monosaccharide composition, which could influence their utilization by various gut microorganisms. The present study aimed to investigate the effects of molar mass and chemical structure of wheat arabinoxylan fiber (AX) on the growth and metabolism of two key gut resident bacteria (Faecalibacterium prausnitzii and Lacticaseibacillus rhamnosus LGG), which are linked to human health. For this purpose, low, medium, and high molar masses of AX (LAX, MAX, and HAX, respectively) were modified with specific α-arabinofuranosidases to leave only singly substituted, only doubly substituted, or unsubstituted xylose units. Almost all the modified AX samples showed a better prebiotic score than unmodified AX for different molar masses. The modified LAX exhibited a better prebiotic effect than HAX and MAX. In addition, LAX, with doubly substituted xylose units, exhibited the highest prebiotic potential and SCFA production by both microorganisms. Furthermore, AX, either singly or doubly substituted, had a consistent impact on L. rhamnosus growth, whereas AX, with all arabinose residues removed, had a greater impact on F. prausnitzii. These findings support the potential of bioengineered AX as next-generation prebiotics targeting health-related gut microbes.

Functional and chemical properties of Phoenix dactylifera l. Polysaccharides and the effect of date flesh and seed intervention on some blood biomarkers: A contrastive analysis

The chemical structure and bioactivity of ultrasonic-assisted alkaline extracted polysaccharides of date seed (DSP) and date flesh (DFP) were investigated. In addition, a crossover clinical trial was conducted to evaluate the effects of 28 days of date seed powder and date flesh consumption on blood biomarkers. Xylose (72.2 %) and galactose (41.6 %) were the most abundant monosaccharides in DSP and DFP, also DFP had a higher uronic acid content (12.16 ± 2.13 g/100 g) compared to DSP (5.57 ± 1.2 g/100 g). DSP had higher proliferation and antibacterial effects compared to DFP and inulin. Bifidobacterium animalis produced a higher short-chain fatty acid concentration during fermentation of DSP (66.98 ± 4.33 mM) and DFP (58.58 ± 5.57 mM) than inulin (19.68 ± 3.73 mM). Date seed powder could significantly reduce C-reactive proteins and triglycerides and increase red blood cell count (p < 0.05). DSP showed considerable prebiotic capability, antibacterial activity, and health-promoting effect; therefore, it could be considered for further investigation as nutraceuticals.

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.

Influence of chemical modifications on dynamic rheological behaviour, thermal techno-functionalities, morpho-structural characteristics and prebiotic activity of banana starches

Banana starch is explored for its use in food and pharmaceutical applications. In this study, in order to improve the techno-functional properties of native banana starch (NS), different chemical modifications namely acid thinning (AT), oxidation (OX), sodium-trimetaphosphate method (STMP), cross linking phosphorylation (CLP), hydroxypropylation (HYP) were employed. Among the modified starches, amylose content was higher in CLP starch and the least was observed in AT. Resistant starch (RS) of HYP (65.38 %) and CLP starches (62.76 %) were significantly higher than other modified starches. Lesser amylose, higher water solubility and lower swelling of AT starch resulted in inferior paste clarity and inability to make a firm gel. Non-Newtonian behaviour of starch gels were observed from static viscosity observations. The dynamic rheological behaviour of the starch gels affirmed the higher gel strength of STMP (0.46) and CLP (0.56) starches. Imperfection and exo-corrosion in starch morphology was observed through SEM and influence of chemicals on the starch structure was elucidated through FTIR and XRD analyses. Except AT starch, modified starches with higher RS resulted in lowering glycemic index (57-69 %). STMP starches recorded highest prebiotic activity score of 0.88. Chemical modifications enable to enhance the functionalities of banana starch and offers potential industrial uses.

Regulation strategy, bioactivity, and physical property of plant and microbial polysaccharides based on molecular weight

Structural features affect the bioactivity, physical property, and application of plant and microbial polysaccharides. However, an indistinct structure-function relationship limits the production, preparation, and utilization of plant and microbial polysaccharides. Molecular weight is an easily regulated structural feature that affects the bioactivity and physical property of plant and microbial polysaccharides, and plant and microbial polysaccharides with a specific molecular weight are important for exerting their bioactivity and physical property. Therefore, this review summarized the regulation strategies of molecular weight via metabolic regulation; physical, chemical, and enzymic degradations; and the influence of molecular weight on the bioactivity and physical property of plant and microbial polysaccharides. Moreover, further problems and suggestions must be paid attention to during regulation, and the molecular weight of plant and microbial polysaccharides must be analyzed. The present work will promote the production, preparation, utilization, and investigation of the structure-function relationship of plant and microbial polysaccharides based on their molecular weight.

Longan pulp polysaccharides regulate gut microbiota and metabolites to protect intestinal epithelial barrier

Longan pulp polysaccharide is a bioactive component with prebiotic activity and intestinal barrier protection. This study aimed to evaluate the influence of digestion and fermentation on the bioavailability and intestinal barrier protection of polysaccharide LPIIa from longan pulp. The molecular weight of LPIIa didn't change significantly after gastrointestinal digestion in vitro. After fecal fermentation, 56.02% of LPIIa was consumed by gut microbiota. The short-chain fatty acid level in LPIIa group was 51.63% higher than that in blank group. LPIIa intake also increased short-chain fatty acid production and G-protein-coupled receptor 41 expression in the colon of mice. Moreover, LPIIa improved the relative richness of Lactobacillus, Pediococcus, and Bifidobacterium in colon content. Compared to LPIIa, fecal fermented LPIIa better protected intestinal epithelial barrier by increasing Zonula occludens-1 expression. These results provided an important basis for the design of functional food based on longan polysaccharides to prevent intestinal barrier damage related diseases.

Structural characterization and anti-inflammatory activity of a novel neutral polysaccharide isolated from Smilax glabra Roxb

Crude polysaccharides isolated from Smilax glabra were screened for anti-inflammatory activity using mice ear swelling animal experiments, during which the neutral polysaccharide S1 was identified. The structural characteristics and anti-inflammatory effects of the anti-inflammatory S1 polysaccharide were then investigated. The results showed that S1 was mainly composed of rhamnose, arabinose, galactose, glucose, xylose, and mannose. The structure of the main chain consisted of →6)-α-Galp-(1 → 6)-β-Galp-(1 → 4)-α-Xylp-(1 → 6)-β-Galp-(1→, with branched chains comprising α-Araf-(1 → 4)-α → Manp-(1 → and β-Rhap-(1 → 4)-α-Glcp-(1 → units. Furthermore, S1 did not have a triple helix conformation. S1 could inhibit NO secretion, reduce the levels of pro-inflammatory factors (IL-6 and TNF-α), and significantly reduce LPS-stimulated inflammatory damage in RAW 264.7 cells by inhibiting activation of the NF-κB (p65) pathway. These results shed light on the possibility of S1 to be developed as a novel anti-inflammatory drug for therapeutic purposes.

Effects of Steaming on Sweet Potato Soluble Dietary Fiber: Content, Structure, and Lactobacillus Proliferation In Vitro

The influence of steaming treatment on the soluble dietary fiber (SDF) of sweet potato was investigated. The SDF content increased from 2.21 to 4.04 g/100 g (in dry basis) during 20 min of steaming. The microcosmic morphology of the fractured cell wall indicated the release of SDF components during steaming. The SDF from fresh (SDF-F) and 20 min steamed (SDF-S) sweet potato was characterized. The neutral carbohydrates and uronic acid levels in SDF-S were significantly higher than SDF-F (59.31% versus 46.83%, and 25.36% versus 9.60%, respectively) (p < 0.05). The molecular weight of SDF-S was smaller than SDF-F (5.32 kDa versus 28.79 kDa). The probiotic property was evaluated by four Lactobacillus spp. fermentation in vitro with these SDF as carbon source, using inulin as the references. SDF-F showed the best proliferation effects on the four Lactobacillus spp. in terms of the OD₆₀₀ and pH in cultures, and the highest production of propanoic acid and butyric acid after 24 h fermentation. SDF-S presented higher Lactobacillus proliferation effects, but slight lower propanoic acid and butyric acid production than inulin. It was concluded that 20 min of steaming released SDF with inferior probiotic properties, which might derive from the degraded pectin, cell wall components, and resistant dextrin.

Insights into the Oxidative Stress Alleviation Potential of Enzymatically Prepared Dendrobium officinale Polysaccharides

(1) Background: The extraction parameters can dramatically alter the extraction rate and biological activity of polysaccharides. (2) Methods: Here, an enzyme-assisted extraction (EAE) was employed to extract D. officinale polysaccharides (DOPs), and its optimal extraction conditions were established by single-factor and Box-Behnken design (BBD) experiments. Further, on the basis of in vitro antioxidant capacity, the paraquat (PQ)-induced oxidative stress of Caenorhabditis elegans (C. elegans) was chosen as a research model to explore the antioxidant activity of DOPs. (3) Results: The results showed that the extraction yield of DOPs reached 48.66% ± 1.04% under the optimal condition. In vitro experiments had shown that DOPs have considerable ABTS⁺ radical scavenging capacity (EC50 = 7.27 mg/mL), hydroxyl radical scavenging capacity (EC50 = 1.61 mg/mL), and metal chelating power (EC50 = 8.31 mg/mL). Furthermore, in vivo experiments indicated that DOPs (0.25 mg/mL) significantly prolonged the lifespan, increased antioxidant enzyme activity, and upregulated the expression of daf-16 (>5.6-fold), skn-1 (>5.2-fold), and sir-2.1 (>2.3-fold) of C. elegans. (4) Conclusions: DOPs can be efficiently extracted by EAE and are effective in the reduction of oxidative stress levels in C. elegans.

Effects of simulated digestion on the structural characteristics and dendritic cell activation of longan polysaccharides

An active polysaccharide (LP) from longan was purified and characterized. LP consisted of galactose and glucose in a molar ratio of 1.5: 98.5, with a molecular weight of 4.67 × 10⁷ g/mol. The main backbone of LP was T-α-D-Glcp-[(1 → 6)-α-D-Glcp-(1 → 6)-α-D-Glcp]_n. After simulated gastrointestinal digestion, the molecular weight distribution, monosaccharide composition, and major glycosidic bonds of LP were not significantly changed. LP and digested LP (DLP) reduced phagocytosis and promoted IL-10 and IL-12 secretion of dendritic cells. In addition, the effects of LP and DLP on activating dendritic cells showed no significant difference. This study helps to illuminate the potential mode of immunomodulatory action of longan polysaccharides in vivo.

Influence of Enzymatic Hydrolysis on Composition and Technological Properties of Apple Pomace and Its Application for Wheat Bread Making

The aim of this work was to evaluate the influence of enzymatic hydrolysis on dietary fiber, phenolic compounds and technological properties of apple pomace as wheat bread supplement. Apple pomace was hydrolyzed with Viscozyme® L, Pectinex® Ultra Tropical, Celluclast® 1.5 L for 1 and 5 h. Soluble (SDF) and insoluble (IDF) dietary fiber, reducing sugars and the total phenolic contents (TPC), along with the technological properties (water and oil retention capacities, solubility index, emulsion stability) of treated apple pomace were evaluated. The prebiotic activity of apple pomace water-soluble fraction on two probiotic strains Lactobacillus acidophilus DSM 20079 and Bifidobacterium animalis DSM 20105 was investigated. Treatment with Celluclast® 1.5 L increased SDF, reducing sugars, SDF/IDF ratio and decreased IDF of apple pomace. While treatment with Viscozyme® L, Pectinex® Ultra Tropical increased reducing sugars, solubility index and TPC, but in most cases reduced oil and water retention capacities, decreased SDF and IDF content. All apple pomace extracts promoted growth of probiotic strains. Addition of 5% of apple pomace hydrolyzed with Celluclast® 1.5 L did not have negative impact on wheat bread, while addition of other enzymatically hydrolyzed apple pomaces decreased pH, specific volume and porosity of wheat bread. Obtained results suggest that apple pomace enzymatically hydrolyzed with Celluclast® 1.5 L can be potentially used for wheat bread supplementation with dietary fiber.

Polysaccharides from Nitraria retusa Fruit: Extraction, Purification, Structural Characterization, and Antioxidant Activities

Polysaccharides are important bioactive components of Nitraria retusa fruit (NRF). In this study, the ultrasonic-assisted extraction (UAE) conditions of polysaccharides from Nitraria retusa fruit (NRFPs) were optimized by response surface methodology (RSM). The structural characteristics and antioxidant activity were investigated. The maximum NRFPs yield of 3.35% was obtained under the following optimal conditions: temperature of 59.5 °C, time of 30.5 min, liquid-to-solid ratio of 19.5 mL/g. Three polysaccharide fractions, NRFP-1 (20.01 kDa), NRFP-2 (28.96 kDa), and NRFP-3 (67.45 kDa), were isolated. Glucose, galactose, and arabinose in different percentages were identified as the primary monosaccharide units. The Fourier transform infrared spectrometer (FT-IR) and nuclear magnetic resonance (NMR) analysis indicated the presence of α- and β-glycosidic bonds in NRFPs. The NRFP-3 exhibited the highest scavenging activities against DPPH, ABTS, -OH free radicals, and Fe⁺³-reducing activity.

Purification, Characterization and Bioactivity of Different Molecular-Weight Fractions of Polysaccharide Extracted from Litchi Pulp

Litchi polysaccharides are a kind of macromolecular polymers with various biological activities and a wide range of molecular weights. In this study, two separate fractions, with average molecular weights of 378.67 kDa (67.33%) and 16.96 kDa (6.95%), which were referred to as LP1 and LP2, respectively, were separated using an ultrafiltration membrane. Their physicochemical properties, and immunomodulatory and prebiotic activity were compared. The results revealed that LP2 contained more neutral sugar, arabinose, galactose and rhamnose, but less uronic acid, protein, mannose and glucose than LP1. Compared with LP1, LP2 possessed higher solubility and lower apparent viscosity. LP2 exhibited stronger stimulation on macrophage secretion of NO, TNF-α and IL-6, as well as better proliferation of Lactobacillus plantarum, Leuconostoc mesenteroides, Lactobacillus casei and Bifidobacterium adolescentis. These results suggest that an ultrafiltration membrane might be used to prepare a highly-active polysaccharide fraction from litchi pulp that may be used for food or drug development.

Effects of Carboxymethyl Modification on the Acidic Polysaccharides from Calocybe indica: Physicochemical Properties, Antioxidant, Antitumor and Anticoagulant Activities

An acidic polysaccharide fraction was obtained from Calocybe indica (CIP3a) after subjecting it to hot water extraction followed by purification through DEAE-cellulose 52 and Sepaharose 6B column chromatography. The CIP3a was further modified using chloroacetic acid to yield carboxymethylated derivatives (CMCIP3a). The modified polysaccharide was characterized using various spectroscopic methods. In addition, further antioxidant, antitumor and anticoagulant activities were also investigated. The polysaccharides CIP3a and CMCIP3a were heterogeneous in nature and composed of various molar percentages of glucose, arabinose and mannose with molecular weights of 1.456 × 10³ and 4.023 × 10³ Da, respectively. The NMR and FT-IR data demonstrated that the carboxymethylation on the polysaccharide was successful. In comparison to CIP3a polysaccharides, the modified derivatives had lower sugar and protein contents, and higher levels of uronic acid. The in vitro antioxidant activity showed that CMCIP3a with higher molecular weight displayed an elevated ability in scavenging the DPPH radical, ABTS, superoxide, hydroxyl radical, ferric reducing power, cupric reducing power and erythrocyte hemolysis inhibition with an EC₅₀ value of 2.49, 2.66, 4.10, 1.60, 3.48, 1.41 and 2.30 mg/mL, respectively. The MTT assay results revealed that CMCIP3a displayed a dose-dependent inhibition on five cancer cells (HT29, PC3, HeLa, Jurkat and HepG-2) in the range of 10-320 μg/mL. The APTT, PT and TT were significantly extended by CMCIP3a in relation to dosage, indicating that the anticoagulant effect of CIP was both extrinsic and intrinsic, along with a common coagulation pathway. These findings demonstrated that carboxymethylation might effectively improve the biological potential of the derivatives and offer a theoretical framework for the creation of novel natural antioxidants, low-toxicity antitumor and antithrombotic drugs.

Physicochemical properties and prebiotic activities of polysaccharides from Zizyphus jujube based on different extraction techniques

Zizyphus jujube polysaccharide was extracted with hot water, ultrahigh pressure, deep eutectic solvent (DES) and ultrahigh pressure-assisted DES. Comparative analyses were conducted on the yield, physicochemical properties and prebiotic activity of four polysaccharides (JP-H, JP-U, JP-D and JP-UD). The yield of JP-UD (10.42 %) was 3.3 times that of JP-H (3.12 %), and its sugar content was the highest. JP-UD possessed the lowest Mw, while JP-H possessed the highest. Four JPs were acidic pyranose and mainly composed of galacturonic acid, arabinose and galactose. NMR results demonstrated that they contained not only similar glycosidic linkage but also the specific glycosidic linkage of →4)-α-D-Glcp-(l→ appeared in JP-U and JP-UD, the esterified units of GalA and CONH₂ group appeared in JP-D and JP-UD, and the Terminal β-D-Galp and →4)-α-GalpA-(1→ appeared in JP-UD. JPs showed different proliferation effects on four lactobacillus strains, among which JP-UD exhibited the strongest prebiotic activity. Zizyphus jujube polysaccharides have great potential for application in the functional food and medical industry.

The promotion mechanism of prebiotics for probiotics: A review

Prebiotics and probiotics play a positive role in promoting human nutrition and health. Prebiotics are compounds that cannot be digested by the host, but can be used and fermented by probiotics, so as to promote the reproduction and metabolism of intestinal probiotics for the health of body. It has been confirmed that probiotics have clinical or health care functions in preventing or controlling intestinal, respiratory, and urogenital infections, allergic reaction, inflammatory bowel disease, irritable bowel syndrome and other aspects. However, there are few systematic summaries of these types, mechanisms of action and the promotion relationship between prebiotics and probiotic. Therefore, we summarized the various types of prebiotics and probiotics, their individual action mechanisms, and the mechanism of prebiotics promoting probiotics in the intestinal tract. It is hoped this review can provide new ideas for the application of prebiotics and probiotics in the future.

Research Progress on the Protective Effect of Brown Algae-Derived Polysaccharides on Metabolic Diseases and Intestinal Barrier Injury

In the human body, the intestine is the largest digestive and immune organ, where nutrients are digested and absorbed, and this organ plays a key role in host immunity. In recent years, intestinal health issues have gained attention and many studies have shown that oxidative stress, inflammation, intestinal barrier damage, and an imbalance of intestinal microbiota may cause a range of intestinal diseases, as well as other problems. Brown algae polysaccharides, mainly including alginate, fucoidan, and laminaran, are food-derived natural products that have received wide attention from scholars owing to their good biological activity and low toxic side effects. It has been found that brown algae polysaccharides can repair intestinal physical, chemical, immune and biological barrier damage. Principally, this review describes the protective effects and mechanisms of brown algae-derived polysaccharides on intestinal health, as indicated by the ability of polysaccharides to maintain intestinal barrier integrity, inhibit lipid peroxidation-associated damage, and suppress inflammatory cytokines. Furthermore, our review aims to provide new ideas on the prevention and treatment of intestinal diseases and act as a reference for the development of fucoidan as a functional product for intestinal protection.

Extraction, purification, structural features and biological activities of longan fruit pulp (Longyan) polysaccharides: A review

Dimocarpus longan Lour. (also called as longan) is a subtropical and tropical evergreen tree belonging to the Sapindaceae family and is widely distributed in China, Southeast Asia and South Asia. The pulp of longan fruit is a time-honored traditional medicinal and edible raw material in China and some Asian countries. With the advancement of food therapy in modern medicine, longan fruit pulp as an edible medicinal material is expected to usher in its rapid development as a functional nutrient. As one of the main constituents of longan fruit pulp, longan fruit pulp polysaccharides (LPs) play an indispensable role in longan fruit pulp-based functional utilization. This review aims to outline the extraction and purification methods, structural characteristics and biological activities (such as immunoregulatory, anti-tumor, prebiotic, anti-oxidant, anti-inflammatory and inhibition of AChE activity) of LPs. Besides, the structure-activity relationship, application prospect and patent application of LPs were analyzed and summarized. Through the systematic summary, this review attempts to provide a theoretical basis for further research of LPs, and promote the industrial development of this class of polysaccharides.

Technological Properties and Composition of Enzymatically Modified Cranberry Pomace

Cranberry pomace obtained after juice production is a good source of dietary fiber and other bioactive compounds. In this study, cranberry pomace was hydrolyzed with Viscozyme® L, Pectinex® Ultra Tropical, Pectinex® Yieldmash Plus, and Celluclast® 1.5L (Novozyme A/S, Denmark). The soluble and insoluble dietary fiber was determined using the Megazyme kit, while the changes in mono-, disaccharide and oligosaccharides’ contents were determined using HPLC-RI; the total phenolic contents were determined by Folin−Ciocalteu’s Assay. Prebiotic activity, using two probiotic strains Lactobacillus acidophilus DSM 20079 and Bifidobacterium animalis DSM 20105, was investigated. The technological properties, such as hydration and oil retention capacity, were evaluated. The enzymatic treatment increased the yield of short-chain soluble saccharides. The highest oligosaccharide content was obtained using Viscozyme® L and Pectinex® Ultra Tropical. All of the tested extracts of cranberry pomace showed the ability to promote growth of selected probiotic bacteria. The insoluble dietary fiber content decreased in all of the samples, while the soluble dietary fiber increased just in samples hydrolyzed with Celluclast® 1.5L. The highest content of total phenolic compounds was obtained using Viscozyme® L and Pectinex® Ultra Tropical (10.9% and 13.1% higher than control, respectively). The enzymatically treated cranberry pomace exhibited lower oil and water retention capacities in most cases. In contrast, water swelling capacity increased by 23% and 70% in samples treated with Viscozyme® L and Celluclast® 1.5L, respectively. Enzymatically treated cranberry pomace has a different composition and technological properties depending on the enzyme used for hydrolysis and can be used in various novel food products.

Physical Properties and Prebiotic Activities (Lactobacillus spp.) of Gelatine-Based Gels Formulated with Agave Fructans and Agave Syrups as Sucrose and Glucose Substitutes

This research developed model foods of gelatine-based gels, where carbohydrates from Agave tequilana Weber var. Azul (agave syrups or/and agave fructans) were incorporated into gel formulations as healthy sucrose and glucose substitutes. The sugars (sucrose and glucose) were substituted by agave carbohydrates (agave syrups and agave fructans), obtaining the subsequent gel formulations: 100% agave syrup (F2 gel), 100% agave fructan (F3 gel), and 50% agave syrup−50% agave fructan (F4 gel). The unsubstituted gel formulation was used as a control (F1 gel). The prebiotic activities, physical properties, thermal stability (HP-TLC), and texture of gelatine-based gels were evaluated. The gel formulations showed translucent appearances with approximately 36 g/100 g of water and water activities values between 0.823 and 0.929. The HP-TLC analysis validated that agave fructans did not hydrolyse during the thermal process of gels production. Gels produced with agave syrup and agave fructan (F2-F4 gels) provided higher hardness, gumminess, and springiness values (p < 0.05) than those produced with glucose and sucrose (F1 gel). Gelatine-based gel formulations displayed prebiotic activities correlated to the ability of Lactobacillus plantarum, Lactobacillus paracasei, and Lactobacillus rhamnosus to use agave carbohydrates as carbon sources. Based on the prebiotic effect and physical and textural properties, the F2 and F4 gel formulations displayed the best techno-functional properties to produce gel soft candies.

Two Natural Flavonoid Substituted Polysaccharides from Tamarix chinensis: Structural Characterization and Anticomplement Activities

Two novel natural flavonoid substituted polysaccharides (MBAP-1 and MBAP-2) were obtained from Tamarix chinensis Lour. and characterized by HPGPC, methylation, ultra-high-performance liquid chromatography-ion trap tandem mass spectrometry (UPLC-IT-MSⁿ), and NMR analysis. The results showed that MBAP-1 was a homogenous heteropolysaccharide with a backbone of 4)-β-d-Glcp-(1→ and →3,4,6)-β-d-Glcp-(1→. MBAP-2 was also a homogenous polysaccharide which possessed a backbone of →3)-α-d-Glcp-(1→, →4)-β-d-Glcp-(1→ and →3,4)-β-d-Glcp-2-OMe-(1→. Both the two polysaccharides were substituted by quercetin and exhibited anticomplement activities in vitro. However, MBAP-1 (CH₅₀: 0.075 ± 0.004 mg/mL) was more potent than MBAP-2 (CH₅₀: 0.249 ± 0.006 mg/mL) and its reduced product, MBAP-1R (CH₅₀: 0.207 ± 0.008 mg/mL), indicating that multiple monosaccharides and uronic acids might contribute to the anticomplement activity of the flavonoid substituted polysaccharides of T. chinensis. Furthermore, the antioxidant activity of MBAP-1 was also more potent than that of MBAP-2. In conclusion, these two flavonoid substituted polysaccharides from T. chinensis were found to be potential oxidant and complement inhibitors.

Enhanced Growth Inhibition and Apoptosis Induction in Human Colon Carcinoma HT-29 Cells of Soluble Longan Polysaccharides with a Covalent Chemical Selenylation

The selenylated polysaccharides chemically belong to the organic Se-conjugated macromolecules and have recently been attracting more and more attention due to their potential to promote body health or prevent cancers. Longan (Dimocarpus longan L.), as a subtropical fruit, contains soluble and non-digestible polysaccharides that are regarded with health care functions in the body. In this study, the longan polysaccharides (LP) were obtained via enzyme-assisted water extraction, and then chemically selenylated using a reaction system composed of HNO₃–Na₂SeO₃ to yield two selenylated products, namely, SeLP1 and SeLP2, with Se contents of 1.46 and 4.79 g/kg, respectively. The anti-cancer effects of the three polysaccharide samples (LP, SeLP1, and SeLP2) were thus investigated using the human colon cancer HT-29 cells as the cell model. The results showed that SeLP1 and SeLP2 were more able than LP to inhibit cell growth, alter cell morphology, cause mitochondrial membrane potential loss, increase intracellular reactive oxygen and [Ca²⁺]_i levels, and induce apoptosis via regulating the eight apoptosis-related genes and proteins including Bax, caspases-3/-8/-9, CHOP, cytochrome c, DR5, and Bcl-2. It was thereby proven that the selenylated polysaccharides could induce cell apoptosis via activating the death receptor, mitochondrial-dependent, and ER stress pathways. Collectively, both SeLP1 and SeLP2 showed higher activities than LP in HT-29 cells, while SeLP2 was consistently more active than SeLP1 in exerting these assessed anti-cancer effects on the cells. In conclusion, this chemical selenylation covalently introduced Se into the polysaccharide molecules and caused an enhancement in their anti-cancer functions in the cells, while higher selenylation extent was beneficial to the activity enhancement of the selenylated products.

Modulatory effects of longan seed powder on growth performance, immune response, and immune-antioxidant related gene expression in Nile tilapia (Oreochromis niloticus) raised under biofloc system

This study evaluates the effects of longan seed powder (LS) on the growth performance, immunological response, and immune-antioxidant related gene expression of Nile tilapia (Oreochromis niloticus). Three hundred fish (13.82 ± 0.06 g) were divided into five experiments and fed 5 diets, including the basal diet (control without LS) and basal diet containing 10 (LS10), 20 (LS20), 40 (LS40), and 80 (LS80) g kg^-1 LS for eight weeks. A completely randomized design (CRD) with three replications was utilised. The growth performance and immune response were measured at weeks 4 and 8 post feeding, while the gene expressions were determined at the end of the feeding trial. The results revealed that administration of LS could significantly (P < 0.05) improve specific growth rate (SGR), weight gain (WG), and feed conversion ratio (FCR) in Nile tilapia as compared to the control group. However, no significant differences (P > 0.05) were observed in survival rates among treatments. LS-supplemented diets showed enhanced serum peroxidase activity (SPA), serum lysozyme activity (SLA), skin mucus lysozyme activity (MLA), and skin mucus peroxidase activity (MPA) at weeks 4 and 8 post-feeding, with the highest values observed in the LS20 diet (P < 0.05). Additionally, LS-supplemented diets significantly up-regulated (P < 0.05) immune and antioxidant related gene expressions (IL1, IL8, LBP, GSTa, GPX, and GSR) in the liver and intestine, with highest values observed in the LS20 treatment. The present results confirmed the beneficial effects of LS as a functional feed additive and immunostimulant for Nile Tilapia culture in a biofloc system.

Acidic electrolyzed water treatment retards softening and retains cell wall polysaccharides in pulp of postharvest fresh longans and its possible mechanism

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AEW delayed pulp softening of longans via suppressing cell wall disassembly.

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AEW down-regulated expression levels of longan pulp cell wall degrading-related genes.

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AEW decreased activities of cell wall degrading enzymes in pulp of harvested longans.

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AEW retained higher levels of longan pulp CWM, CSP, ISP, cellulose, and hemicellulose.

Effects of acidic electrolyzed water (AEW) treatment (pH = 2.5, ACC = 80 mg L⁻¹, 10 min) on pulp firmness, amounts of CWM and CWP, activities and expression of relevant genes of CWDEs in pulp of Fuyan longan during storage at 25 °C were evaluated. Compared to control samples, during storage, AEW-treated fruit retained a higher pulp firmness, prevented WSP formation, reduced the degradation of CSP, cellulose and hemicellulose, and lowered CWDEs activities and their corresponding gene expression. When stored for 5 d, pulp firmness (113.6 g mm⁻¹), CWM (13.9 g kg⁻¹), and CSP (1.4 g kg⁻¹) in AEW-treated fruit displayed the clearly higher contents than those in control samples. These data suggest that AEW treatment can slow down the pulp softening and retain higher pulp CWP levels in postharvest fresh longans, which was because AEW lowered activities of CWDEs and its gene expression levels, and maintained the cell wall structure's integrity.

Recent advances in biotransformation, extraction and green production of D-mannose

D-mannose is a natural and biologically active monosaccharide. It is the C-2 epimer of glucose and a component of a variety of polysaccharides in plants. In addition, D-mannose also naturally exists in some cells of the human body and participates in the immune regulation of cells as a prebiotic. Its good physiological benefits to human health and wide application in the food and pharmaceutical industries have attracted widespread attention. Therefore, in-depth research on preparation methods of D-mannose has been widely developed. This article summarizes the main production methods of D-mannose in recent years, especially the in-depth excavation from biomass raw materials such as coffee grounds, konjac flour, acai berry, etc., to provide new ideas for the green manufacture of D-mannose.

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Various methods of recent mannose production were comprehensively summarized.

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The new technical progress of obtaining mannose from biomass as emphatically discussed.

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Discuss various preparation methods including different pretreatments, enzymatic hydrolysis, etc.

Activities of the soluble and non-digestible longan (Dimocarpus longan Lour.) polysaccharides against HCT-116 cells as affected by a chemical selenylation

The soluble and non-digestible longan (Dimocarpus longan Lour.) polysaccharides (LP) with Se content less than 0.01 g/kg were extracted and selenylated chemically with the HNO₃–Na₂SeO₃ system, to prepare two selenylated products namely SeLP1 and SeLP2 with enhanced Se contents of 1.46 and 4.79 g/kg, respectively. LP, SeLP1, and SeLP2 were then measured and compared for their saccharide features and bioactivity in human colon carcinoma HCT-116 cells. Compared with LP, both SeLP1 and SeLP2 contained more neutral saccharides, but showed reduced uronic acid content and undetectable sulfate. Moreover, SeLP1 and especially SeLP2 in the cells showed higher activities than LP, reflected by their enhanced capacity to inhibit cell growth, alter cell morphology, and suppress cell colony formation. Compared with LP, SeLP1 and especially SeLP2 were also more capable of promoting intracellular reactive oxygen species and Ca²⁺ levels, causing mitochondrial membrane potential loss, or inducing cell apoptosis via up- and down-regulating the eight apoptosis-related genes and proteins. Overall, the performed chemical selenylation of LP resulted in obvious changes in these saccharide features and simultaneously enhanced the anti-cancer activity of the selenylated products against the cells clearly, while a higher selenylation extent of the selenylated products consistently caused higher activity towards the cells. The results of this study thus highlighted that this chemical selenylation is applicable when aiming to enhance the bioactivities of natural polysaccharides.

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Chemical selenylation of longan polysaccharides causes Se conjugation covalently.

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The selenylated polysaccharides have changes in saccharide features and sulfate.

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The selenylated polysaccharides have higher activities to HCT-116 cells.

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Higher polysaccharide selenylation consistently leads to activity increase in cells.

The Extraction, Functionalities and Applications of Plant Polysaccharides in Fermented Foods: A Review

Plant polysaccharides, as prebiotics, fat substitutes, stabilizers, thickeners, gelling agents, thickeners and emulsifiers, have been immensely studied for improving the texture, taste and stability of fermented foods. However, their biological activities in fermented foods are not yet properly addressed in the literature. This review summarizes the classification, chemical structure, extraction and purification methods of plant polysaccharides, investigates their functionalities in fermented foods, especially the biological activities and health benefits. This review may provide references for the development of innovative fermented foods containing plant polysaccharides that are beneficial to health.