Quantification of Paeoniflorin by Fully Validated LC-MS/MS Method: Its Application to Pharmacokinetic Interaction between Paeoniflorin and Verapamil.

A rapid, sensitive, and specific LC-MS/MS method was developed and fully validated for the detection of paeoniflorin only in rat plasma, and applied to pharmacokinetic studies, including intravenous, multi-dose oral and combined administrations with verapamil. In this study, tolbutamide was used as the internal standard, and the protein precipitation extraction method, using acetonitrile as the extraction agent, was used for the sample preparation. Subsequently, the supernatant samples were analyzed on a Phenomenex Gemini® NX-C18 column with a flow rate of 1.0 mL/min in a gradient elution procedure. In the extracted rat plasma, the method exhibited high sensitivity (LLOQ of 1.0 ng/mL) upon selecting ammonium adduct ions ([M+NH4]+) as the precursor ions and good linearity over the concentration range of 1.0−2000 ng/mL, with correlation coefficients >0.99. The intra- and inter-batch accuracy RE% values were within ±8.2%, and the precision RSD% values were ≤8.1% and ≤10.0%, respectively. The results show that the method can be successfully applied to quantitate paeoniflorin in biological samples. Additionally, paeoniflorin is subsequently confirmed to be the substrate of the P-gp transporter in vivo and in vitro for the first time, which would be necessary and beneficial to investigate the clinical safety and efficacy of PF with other drugs in the treatment of rheumatoid arthritis.

A mutant-cell library for systematic analysis of heparan sulfate structure-function relationships.

Heparan sulfate (HS) is a complex linear polysaccharide that modulates a wide range of biological functions. Elucidating the structure-function relationship of HS has been challenging. Here we report the generation of an HS-mutant mouse lung endothelial cell library by systematic deletion of HS genes expressed in the cell. We used this library to (1) determine that the strictly defined fine structure of HS, not its overall degree of sulfation, is more important for FGF2-FGFR1 signaling; (2) define the epitope features of commonly used anti-HS phage display antibodies; and (3) delineate the fine inter-regulation networks by which HS genes modify HS and chain length in mammalian cells at a cell-type-specific level. Our mutant-cell library will allow robust and systematic interrogation of the roles and related structures of HS in a cellular context.

[Study on chemical constituents of Cinnamomi Ramulus].

The chemical constituents of Cinnamomi Ramulus were investigated in this study. Twenty-two compounds were isolated by silica gel, Sephadex LH-20 gel column chromatographies and preparative HPLC and their structures were identified by various spectral analyses as dihydrorosavin(1), rosavin(2), 1-phenyl-propane-1,2,3-triol(3), patchoulol(4), graphostromane B(5),(+)-lyoniresinol-3 a-O-ß-D-glucopyranoside(6),(-)-lyoniresinol-3 a-O-ß-D-glucopyranoside(7), cinnacaside(8), subaveniumin A(9), 3-phenyl-2-propenyl-6-O-L-arabinopyranosyl-ß-glucopyranoside(10), 2-phenylethyl-ß-vicianoside(11), cinnacasol(12), [(2R,3S,4S,5R,6R)-6-(benzyloxy)-3,4,5-trihydroxytetrahydro-2H-pyran-2-yl] methyl hydrogen sulfate(13), coniferyl aldehyde(14),(2R,3R)-5,7-dimethoxy-3',4'-methylenedioxyflavan-3-ol(15), cinnacassin L(16), E-cinnamic alcohol(17),(E)-3-(2-methoxyphenyl)-2-propen-1-ol(18), 2-hydroxyphenylpropanol(19), cinnamomulactone(20),(+)-syringaresinol(21) and cinnamomumolide(22), respectively. Among them, 1 is a new compound and 3-7, 9-11, 13, 15, 18 and 19 were isolated from the plant for the first time.

Anti-complementary activity of two homogeneous polysaccharides from Eclipta prostrata.

Complement-mediated inflammation and tissue damage is an important drive to pathology in autoimmune diseases, targeting inhibit the complement activation is promising treatment strategy for these diseases. We performed anticomplement activity-guided fractionation of the water extract of Eclipta prostrata by ion-exchange and size-exclusion chromatography, yielding two bioactive polysaccharides EAP20-1 and EAP20-2. The molecular weights of EAP20-1 and EAP20-2 were respectively calculated to be 5.2 kDa and 6.3 kDa by HPGPC, both polysaccharides was composed by d-Gal, l-Glc, and Ara at different ratios of 7.3:2.7:1 and 7.6:3.1:1. In addition, the main linkage types of EAP20-1 and EAP20-2 were ß-1,4-Gal, ß-1,6-Gal and α-1,4,6-Glc according to methylation analyses. EAP20-1 and EAP20-2 exhibited significant inhibitory effect on the complement activation through both classical and alternative pathways and with no influence on the coagulation system. Preliminary mechanism study indicated that both EAP20-1 and EAP20-2 inhibited the activation of the complement system by interacting with C1q, C1r, C1s, C2, C4, C5, C7, and C9 components.

Structural characterization and biological activities of two α-glucans from radix paeoniae alba.

Radix Paeoniae Alba is widely used in Chinese traditional medicine to treat various diseases such as gastrointestinal disorders, cancer, and other diseases. In this study, two polysaccharides RPAPW1 and RPAPW2 were isolated from Radix Paeoniae Alba by DEAE-52 cellulose chromatography and G-25 sephadex. According to physicochemical methods, NMR and methylation analysis, RPAPW1 and RPAPW2 were established to be α-glucans consisting of predominant 4-linked α- Glc residues branched at O-6 and contained trace amount of protein and uronic acid. Immunological tests indicated that RPAPW1, RPAPW2 and could promote splenocyte proliferation and RAW264.7 phagocytic activity. In vitro, RPAPW1 and RPAPW2 elicited a week reducing power, DPPH scavenging activity and could not protect the PC12 cells from H2O2 damage. These data implied polysaccharides RPAPW1 and RPAPW2 had the potential to be a natural immunopotentiating and antioxidant supplement for preparing functional foods and nutraceuticals.

A Homogeneous Polysaccharide from Fructus Schisandra chinensis (Turz.) Baill Induces Mitochondrial Apoptosis through the Hsp90/AKT Signalling Pathway in HepG2 Cells.

According to the potential anti-hepatoma therapeutic effect of Schisandra chinensis polysaccharides presented in previous studies, a bioactive constituent, homogeneous Schisandra chinensis polysaccharide-0-1 (SCP-0-1), molecular weight (MW) circa 69.980 kDa, was isolated and purified. We assessed the efficacy of SCP-0-1 against human hepatocellular liver carcinoma (HepG2) cells to investigate the effects of its antitumour activity and molecular mechanisms. Anticancer activity was evaluated using microscopy, 3-[4,5-dimethyl-2-thiazolyl]-2,5-diphenyltetrazolium bromide (MTT) assay, Hoechst 33258 staining, acridine orange (AO) staining, flow cytometry (FCM), and cell-cycle analysis. SCP-0-1 inhibited the HepG2 cells' growth via inducing apoptosis and second gap/mitosis (G2/M) arrest dose-dependently, with a half maximal inhibitory concentration (IC50) value of 479.63 µg/mL. Western blotting of key proteins revealed the apoptotic and autophagic potential of SCP-0-1. Besides, SCP-0-1 upregulated Bcl-2 Associated X Protein (Bax) and downregulated B-cell leukemia/lymphoma 2 (Bcl-2) in the HepG2 cells. The expression of caspase-3, -8, and -9; poly (ADP-ribose) polymerase (PARP); cytochrome c (Cyt C); tumor protein 53 (p53); survivin; sequestosome 1 (p62); microtubule-associated protein 1 light chain-3B (LC3B); mitogen-activated protein kinase p38 (p38); extracellular regulated protein kinases (ERK); c-Jun N-terminal kinase (JNK); protein kinase B (AKT); and heat shock protein 90 (Hsp90) were evaluated using Western blotting. Our findings demonstrate a novel mechanism through which SCP-0-1 exerts its antiproliferative activity and induces mitochondrial apoptosis rather than autophagy. The induction of mitochondrial apoptosis was attributed to the inhibition of the Hsp90/AKT signalling pathway in an extracellular signal-regulated kinase-independent manner. The results also provide initial evidence on a molecular basis that SCP-0-1 can be used as an anti-hepatocellular carcinoma therapeutic agent in the future.

Chemical Structure and Immunomodulating Activities of an α-Glucan Purified from Lobelia chinensis Lour.

A neutral α-glucan, named BP1, with a molecular mass of approximately 9.45 kDa, was isolated from Lobelia chinensis by hot-water extraction, a Q-Sepharose Fast Flow column and Superdex-75 column chromatography. Its chemical structure was characterized by monosaccharide analysis, methylation analysis and analysis of its FT-IR, high performance gel permeation chromatography (HPGPC) and 1D/2D-NMR spectra data. The backbone of BP1 consists of →6α-d-Glcp¹â†’6,3α-d-Glcp¹â†’(6α-d-Glcp¹)x-6,3α-d-Glcp¹-(6α-d-Glcp¹)y→. The side chains were terminal α-d-Glcp¹â†’ and α-d-Glcp¹â†’ (6α-d-Glcp¹)z→4α-d-Glcp¹â†’3α-d-Glcp¹â†’4α-d-Glcp¹â†’ (x + y + z = 5), which are attached to the backbone at O-3 of 3,6α-d-Glcp¹. The results of the effect of BP1 on mouse macrophage cell line RAW 264.7 indicate that BP1 enhances the cell proliferation, phagocytosis, nitric oxide production and cytokine secretion in a dose-dependent manner. Because the inhibitor of Toll-like receptor 4 blocks the BP1-induced secretion of TNF-α and IL-6, we hypothesize that α-glucan BP1 activates TLR4, which mediates the above-mentioned immunomodulating effects.

Oligosaccharide G19 inhibits U-87 MG human glioma cells growth in vitro and in vivo by targeting epidermal growth factor (EGF) and activating p53/p21 signaling.

G19 is a novel homogeneous sulfated oligosaccharide, prepared from Grateloupia filicina. In the present study, we first reported that oligosaccharide G19 exhibited a dose- and time-dependent anti-proliferation effect against U-87 malignant gliomas (MG) human glioma cells. Further studies indicated that G19 strongly bound to epidermal growth factor (EGF), suppressed EGF receptor phosphorylation and interrupted the phosphatidylinositol-3 kinase/Akt pathway in the cancer cells. Moreover, G19 elevated intracellular reactive oxygen species levels and caused endogenous DNA damage. These actions were associated with activation of ataxia-telangiectasia-mutated/checkpoint kinase 2 pathway. The downregulation of MDM2 with stabilizing p53 and the nuclear location of p21 were induced by G19 to cause cell cycle arrest and apoptosis to some extent. Meanwhile, intrinsic mitochondrial pathway and extrinsic death receptor pathway were involved in G19-mediated apoptosis. Pretreatment with free radical scavenger N-acetyl-l-cysteine nearly completely inversed G19-induced cell growth inhibition, cell cycle arrest and apoptosis in U-87 MG cells. Importantly, G19 could inhibit the growth of U-87 MG tumor cells xenograft in nude mice. The results suggested that G19 could be served as a new targeting drug candidate for human glioma treatment.

Chitosan improves anti-biofilm efficacy of gentamicin through facilitating antibiotic penetration.

Antibiotic overuse is one of the major drivers in the generation of antibiotic resistant "super bugs" that can potentially cause serious effects on health. In this study, we reported that the polycationic polysaccharide, chitosan could improve the efficacy of a given antibiotic (gentamicin) to combat bacterial biofilms, the universal lifestyle of microbes in the world. Short- or long-term treatment with the mixture of chitosan and gentamicin resulted in the dispersal of Listeria monocytogenes (L. monocytogenes) biofilms. In this combination, chitosan with a moderate molecular mass (~13 kDa) and high N-deacetylation degree (~88% DD) elicited an optimal anti-biofilm and bactericidal activity. Mechanistic insights indicated that chitosan facilitated the entry of gentamicin into the architecture of L. monocytogenes biofilms. Finally, we showed that this combination was also effective in the eradication of biofilms built by two other Listeria species, Listeria welshimeri and Listeria innocua. Thus, our findings pointed out that chitosan supplementation might overcome the resistance of Listeria biofilms to gentamicin, which might be helpful in prevention of gentamicin overuse in case of combating Listeria biofilms when this specific antibiotic was recommended.

Characterization of two homogalacturonan pectins with immunomodulatory activity from green tea.

Two natural homogalacturonan (HG) pectins (MW ca. 20 kDa) were isolated from green tea based on their immunomodulatory activity. The crude tea polysaccharides (TPS1 and TPS2) were obtained from green tea leaves by hot water extraction and followed by 40% and 70% ethanol precipitation, respectively. Two homogenous water soluble polysaccharides (TPS1-2a and TPS1-2b) were obtained from TPS1 after purification with gel permeation, which gave a higher phagocytic effect than TPS2. A combination of composition, methylation and configuration analyses, as well as NMR (nuclear magnetic resonance) spectroscopy revealed that TPS1-2a and TPS1-2b were homogalacturonan (HG) pectins consisting of a backbone of 1,4-linked α-D-galacturonic acid (GalA) residues with 28.4% and 26.1% of carboxyl groups as methyl ester, respectively. The immunological assay results demonstrated that TPS1-2, which consisted mainly of HG pectins, showed phagocytosis-enhancing activity in HL-60 cells.

Applications of the Yariv reagent in polysaccharide analysis and plant physiology from theory to practice.

Arabinogalactan (AG), a biologically active substance found abundantly in plants, is of significant interest in plant physiology due to its unique physicochemical properties. Yariv reagent, widely utilized in AG-II related applications, forms insoluble precipitates when bound to AG-II. This paper provides a comprehensive overview of the synthesis methods, physicochemical properties, and various dissociation methods of the Yariv reagent to enhance its utility in AG-II studies. Furthermore, the review explores the binding mechanisms and applications of the Yariv reagent, highlighting the advancements in studying the Yariv-AG complex in plant physiology. The aim of this review is to inspire new research ideas and foster novel applications of the Yariv reagent from synthesis to implementation.

Structural characterization of an inulin neoseries-type fructan from Ophiopogonis Radix and the therapeutic effect on liver fibrosis in vivo.

Ophiopogonis Radix is a well-known Traditional Chinese Medicine and functional food that is rich in polysaccharides and has fructan as a characteristic component. In this study, an inulin neoseries-type fructan designated as OJP-W2 was obtained and characterized from Ophiopogonis Radix, and its potential therapeutic effect on liver fibrosis in vivo were investigated. Structural studies revealed that OJP-W2 had a molecular weight of 5.76 kDa and was composed of glucose and fructose with a molar ratio of 1.00:30.87. Further analysis revealed OJP-W2 has a predominantly lineal (1-2)-linked ß-D-fructosyl units linked to the glucose moiety of the sucrose molecule with (2-6)-linked ß-D-fructosyl side chains. Pharmacological studies revealed that OJP-W2 exerted a marked hepatoprotective effect against liver fibrosis, the mechanism of action was involved in regulating collagen deposition (α-SMA, COL1A1 and liver Hyp contents) and TGF-ß/Smads signaling pathway, alleviating liver inflammation (IL-1ß, IL-6, CCL5 and F4/80) and MAPK signaling pathway, and inhibiting hepatic apoptosis (Bax, Bcl-2, ATF4 and Caspase 3). These data provide evidence for expanding Ophiopogonis Radix-acquired fructan types and advancing our understanding of the specific role of inulin neoseries-type fructan in liver fibrosis therapy.

Inulin-like polysaccharide ABWW may impede CCl4 induced hepatic stellate cell activation through mediating the FAK/PI3K/AKT signaling pathway in vitro & in vivo.

Studies have shown that terrestrial acidic polysaccharides containing carboxyl groups and seaweed sulfated polysaccharides have strong potential in anti-liver fibrosis. However, there is no investigation on the anti-liver fibrosis of fructan, a ubiquitous natural polysaccharide. The present study aimed to understand the effect of fructan in ameliorating carbon tetrachloride (CCl4)-induced liver fibrosis in mice. Here, an inulin-like fructan ABWW from Achyranthes bidentata Bl. was characterized by fructose enzymatic hydrolysis, methylation analysis, ESI-MS, and NMR. It was composed of →2)-ß-d-Fruf-(1→ and →2)-ß-d-Fruf-(1, 6→, terminated with →1)-α-d-Glcp and →2)-ß-d-Fruf residues. The biological studies showed that ABWW could improve liver damage and liver fibrosis induced by CCl4in vivo and inhibit hepatic stellate cell (HSC) activation and migration in vitro. We further demonstrated that ABWW inhibited LX2 activation via suppressing the FAK/PI3K/AKT signaling pathway. Hence, ABWW might be a potential novel active compound for anti-fibrosis new drug development.

An arabinogalactan isolated from Cynanchum atratum promotes lymphangiogenesis and lymphatic vessel remodeling to alleviate secondary lymphedema.

Secondary lymphedema is a chronic and incurable disease lacking satisfactory therapeutic drugs. It primarily results from lymphatic vessel dysfunction resulting from factors such as tumor-related surgery, injury, or infection. Promoting lymphangiogenesis and lymphatic vessel remodeling is crucial for restoring tissue fluid drainage and treating secondary lymphedema. In this study, we discovered that the oral administration of a type-II arabinogalactan (CAPW-1, molecular weight: 64 kDa) significantly promoted lymphangiogenesis and alleviated edema in mice with secondary lymphedema. Notably, the tail diameter of the CAPW-1200 group considerably decreased in comparison to that of the lymphedema group, with an average diameter difference reaching 0.98 mm on day 14. CAPW-1 treatment also reduced the average thickness of the subcutaneous area in the CAPW-1200 group to 0.37 mm (compared with 0.73 mm in the lymphedema group). It also facilitated the return of injected indocyanine green (ICG) from the tail tip to the sciatic lymph nodes, indicating that CAPW-1 promoted lymphatic vessel remodeling at the injury site. In addition, CAPW-1 enhanced the proliferation and migration of lymphatic endothelial cells. This phenomenon was associated with the activation of the toll-like receptor 4 (TLR4)/nuclear factor-κB (NF-κB) signaling pathway, thereby promoting the expression of vascular endothelial growth factor-C (VEGF-C), which can be abolished using a TLR4 antagonist. Despite these findings, CAPW-1 did not alleviate the symptoms of lymphedema or restore lymphatic drainage in VEGFR3flox/flox/Prox1-CreERT2 mice. In summary, CAPW-1 alleviates secondary lymphedema by promoting lymphangiogenesis and lymphatic vessel remodeling through the activation of the TLR4/NF-κB/VEGF-C signaling pathway, indicating its potential as a therapeutic lymphangiogenesis agent for patients with secondary lymphedema.

Structural characteristics of steamed Polygonatum cyrtonema polysaccharide and its bioactivity on colitis via improving the intestinal barrier and modifying the gut microbiota.

Steamed Polygonatum cyrtonema has been commonly used clinically for its gaining effect, whose main active ingredient is a polysaccharide. A water-soluble polysaccharide named PSP-W-1 was isolated from steamed Polygonatum cyrtonema. PSP-W-1 was characterized as a galactan having a backbone consisting predominately of 1,4-ß-linked Galp branched at the C-6 position by T-ß-linked Galp with a molecular weight of 14.4 kDa. PSP-W-1 could inhibit the overproduction of inflammatory factors and inflammatory mediators (iNOS, IL-6, COX-2) in dextran sodium sulfate-induced colitis mice. Oral administration of PSP-W-1 dramatically alleviated colonic pathological damage, repaired the intestinal barrier (occludin and ZO-1) and regulated the intestinal microbiota by increasing the abundance of norank_f_Muribaculaceae, Lactobacillus and norank_f_norank_o_Clostridia UCG-014, while decreasing the abundance of Bacteroides and Escherichia-Shigella to alleviate colitis symptoms. Overall, our findings suggest that PSP-W-1 might be a therapeutic option for both the prevention and treatment of colitis.

A decrease in moisture absorption-retention capacity of N-deacetylation of hyaluronic acid.

The linear non-sulfated glycosaminoglycan, hyaluronic acid (HA), is widely distributed throughout connective, epithelial and neural tissues etc., and is of great importance in tissue hydration, lubrication and cellular function. Along with the age growth, HA will lose its acetyl groups under action of HA N-deacetylase in vivo. However, the biological consequence of this physiological process remains largely unknown. Herein two highly N-deacetylated HAs, dHA-6 and dHA-10 were generated via the NH2NH2-HIO3 procedure. Their molecular weights were estimated to be 24 and 16 kDa by high performance gel-permeation chromatography (HPGPC), and the N-deacetylation degrees were 79.4 % and 93 % respectively, as determined by (1)H nuclear magnetic resonance (NMR). The study on moisture-absorption (Ra) and -retention (Rh) abilities demonstrated that the Ra values of dHAs under conditions of 81 % or 43 % relative humidity, as well as the Rh values of dHAs under dry condition or 43 % relative humidity, were significantly smaller than that of their respective re-N-acetylated products. The decline of moisture-absorption and -retention capacity after HA N-deacetylation were consistent with the appearance of unsolvated amides remained in the N-deacetylated products, as indicated by circular dichroism (CD) spectroscopy. Our findings implied that HA N-deacetylation, in addition to the decrease of HA contents in the elderly persons, might account for manifestations of naturally aged skin, such as laxity, sagging, and wrinkling.

Metabolic markers and microecological characteristics of tongue coating in patients with chronic gastritis.

BACKGROUND: In Traditional Chinese Medicine (TCM), tongue diagnosis has been an important diagnostic method for the last 3000 years. Tongue diagnosis is a non-invasive, simple and valuable diagnostic tool. TCM treats the tongue coating on a very sensitive scale that reflects physiological and pathological changes in the organs, especially the spleen and stomach. Tongue coating can diagnose disease severity and determine the TCM syndrome ("Zheng" in Chinese). The biological bases of different tongue coating appearances are still poorly understood and lack systematic investigation at the molecular level. METHODS: Tongue coating samples were collected from 70 chronic gastritis patients and 20 normal controls. 16S rRNA denatured gradient gel electrophoresis (16S rRNA-DGGE) and liquid chromatography and mass spectrometry (LC-MS) were designed to profile tongue coatings. The statistical techniques used were principal component analysis and partial least squares-discriminate analysis. RESULTS: Ten potential metabolites or markers were found in chronic gastritis patients, including UDP-D-galactose, 3-ketolactose, and vitamin D2, based on LC-MS. Eight significantly different strips were observed in samples from chronic gastritis patients based on 16S rRNA-DGGE. Two strips, Strips 8 and 10, were selected for gene sequencing. Strip 10 sequencing showed a 100% similarity to Rothia mucilaginosa. Strip 8 sequencing showed a 96.2% similarity to Moraxella catarrhalis. CONCLUSIONS: Changes in glucose metabolism could possibly form the basis of tongue coating conformation in chronic gastritis patients. The study revealed important connections between metabolic components, microecological components and tongue coating in chronic gastritis patients. Compared with other diagnostic regimens, such as blood tests or tissue biopsies, tongue coating is more amenable to, and more convenient for, both patients and doctors.

[Protection of Grateloupia filicina polysaccharide against hepatotoxicity induced by Dioscorea bulbifera L].

The present study was designed to observe the protection of Grateloupia filicina polysaccharide (GFP) against hepatotoxicity induced by Dioscorea bulbifera L in mice and its underlying mechanism. GFP was intragastrically (ig) given to mice at various doses. After 6 days, the mice were treated with ethyl acetate extract of Dioscorea bulbifera L (EF, ig). Serum levels of alanine/aspartate aminotransferase (ALT/AST), alkaline phosphatase (ALP), total bilirubin (TB) were measured, and liver histological evaluation was conducted. Furthermore, reductions of liver glutathione (GSH) amount and glutamate cysteine ligase (GCL) activity were tested. The expressions of GCL-c, GCL-m, and HO-1 (heme oxygenase-1) in liver were observed by Western-blot. The results showed that GFP (600 mg x kg(-1)) decreased EF-induced the increase of serum ALT, AST and TB, and GFP (400, 600 mg x kg(-1)) inhibited EF-induced the increase of serum ALP. Liver histological evaluation showed that the liver injury induced by EF was relieved after treated with GFP. GFP further increased liver GSH amount and reversed EF-induced the decrease of GCL activity. The Western-blot result showed that GFP augmented EF-induced the increase of HO-1, and reversed EF-induced the decrease of GCL-c. In conclusion, GFP can act against the oxidative stress liver injury induced by Dioscorea bulbifera L in mice.

Versatile functionalization of pectic conjugate: From design to biomedical applications.

Pectin exists extensively in nature and has attracted much attention in biological applications for its unique chemical and physical characteristics. Functionalized pectin, especially pectic conjugates, has given many possibilities for pectin to improve its properties and bioactivity as well as to deliver active molecules. To better exploit this strategy of pectic functionalization, this review presents in detail the structural modifications of pectin, different synthetic methods, and design strategies of pectic conjugates involving both traditional chemical and "green" approaches. Here, the research ideas and applications of pectic prodrugs as well as the development of preparation based on pectic conjugates are reviewed, with emphasis on crosslinking systems of functionalized pectin and nanosystems based on self-assembly techniques. We hope this review will provide comprehensive and valuable information for the functionalization and systematization of the pectic conjugate from synthesis to application.

Review on the genus Polygonatum polysaccharides: Extraction, purification, structural characteristics and bioactivities.

The genus Polygonatum is gaining increasing attention from nutrition experts as well as health-conscious consumers because of its excellent performance in providing nutrients. Among these plants, Polygonatum sibiricum and Polygonatum odoratum have been selected for inclusion in China's Medicinal Food Directory due to their high safety profile. Polysaccharides are considered the main functional component and one of the main active ingredients of the plant. In addition, polysaccharides from genus Polygonatum have a variety of nutritional, biological and health-promoting properties, such as immunomodulatory, anti-inflammatory, cardiovascular protective, neuroprotective, antitumor, antidiabetic, antiosteoporosis, and hepatoprotective properties. This paper reviews the origin, extraction, purification, structural characteristics, biological activity, safety, toxicological evaluation, and structure-activity relationship of polysaccharides from the genus Polygonatum. Ultimately, we hope that this work can provide a more useful reference for understanding the polysaccharide structure and developing of new functional foods from polysaccharides of the genus Polygonatum.