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In this study, Cetraria islandica polysaccharide (CIPs) was extracted by hot water extraction method and its effect on structural modification of immunomodulatory activities was investigated. This polysaccharide mainly consisted of carbohydrates (97.0%), Sulfate (1.2%) with one type of glucose. The average molecular weight (328.7 × 103 g/mol) was determined by size exclusion chromatography. The structure of the polysaccharide was found to be composed of (1→3) and (1→4)-β-D-glucopyranosyl units. The immunomodulatory activities of the crude polysaccharide and its derivatives, over-sulfated (OS1,2,3) and hydrolyzed (H1,2,3), were tested against NK-92 cells and RAW264.7 cells. The results obtained clearly demonstrated that over-sulfated (OS1,2,3)-treated NK-92 cells induced cytotoxicity in HeLa cells through the expressions of IFN-γ, NKp44, NKp30, and FasL. On the other hand, the hydrolyzed derivatives (H1,2,3) activated RAW264.7 cells through production of nitric oxide (NO) and mRNA expression of iNOS, IL-1, TNF-α, IL-6, IL-10 and IL-12 through the nuclear factor kappa-B (NF-κB) and mitogen activated protein kinases (MAPK) pathways. Our findings suggest that the presence of sulfate in the polysaccharide played a pivotal role in NK-92 cell however the Mw was a determinant factor in RAW264.7 cell activation, in which both cells were activated through the CR3 and TLR-4 signaling pathways.

The aqueous polysaccharide from Polygonatum sibiricum was extracted and fractionated using anion-exchange chromatography to obtain F1 fraction. The F1 was chemically sulfated and partially acid-hydrolyzed for the production of its over-sulfated (OS1,2,3) and hydrolyzed (HP1,2,3) derivatives, in which the sulfate content of OS1,2,3 was 7.5–17.1%, and the Mw of HP1,2,3 ranged from 18.2 × 103 to 57.3 × 103 g/mol. Considerable RAW264.7 cell activation was observed by HP1,2,3 with NO production of 34.9, 44.3 and 42.7 μM, respectively, as well as the mRNA expression of cytokines (IL-1β, IL-6, IL-10 and IL-12). NK cell cytotoxicity against HT-29 cell was facilitated by OS1,2,3 treatment with the increased gene expressions of INF-γ, Granzyme-B, perforin, NKG2D, and FasL. RAW264.7 cells appeared to be activated via MR and TLR4 mediated signaling pathway, but CR3 and TRL2 might play a main role in stimulating NK cells. Overall, the present study suggests the potential application of polysaccharides from P. sibiricum in functional foods and pharmacological industries.

Polysaccharides from Boswellia carterii were isolated using hot water and fractionated on a DEAE Sepharose Fast Flow column to evaluate their structural characteristics and macrophage stimulating capacities. Crude and fractionated polysaccharides (BCF1 and BCF2) were mainly consisted of different amounts of neutral sugars (63.7–83.3%) and uronic acids (6.2–22.3%). The weight average molecular weights (Mw) of polysaccharides greatly varied between 295.5 and 504.7 × 103 g/mol. The BCF2 was a highly active polysaccharide on RAW264.7 murine macrophage cells inducing considerable release of nitric oxide and proinflammatory cytokines including TNF-α, IL-1β and IL-6. The presence of p-NF-κB, p-JNK, p-ERK and p-p38 proteins in the cytoplasm of the stimulated macrophages indicated the activation of cells via NF-κB and MAPKs signaling pathways which was followed after CBF2-macrophage interaction through TLR4 and TLR2 receptors. The most potent macrophage activating polysaccharide, BCF2, contained a backbone of (1 → 6)-β-galactopyranosyl units branched at C-3.

A water-soluble polysaccharide was extracted from wheat bran (WBP) and investigate their structural characteristics and immunostimulatory activities. The chemical composition of WBP and purified fraction (WBP-F) mainly consists of neutral sugars (91.2 ± 1.2 and 98.7 ± 1.2%), proteins (8.6 ± 0.3 and 0.2 ± 0.1%) and uronic acids (0.7 ± 0.1 and 0.6 ± 0.1%). The molecular weight (Mw ) of WBP and WBP-F was calculated as 911.7 and 510.2 × 103 g/mol, respectively. The WBP-F stimulates the RAW264.7 cells through the production of nitric oxide and various cytokines. The treatment of WBP-F facilitated the phosphorylation of P38, JNK, ERK, and NF-ƘB in RAW264.7 cells suggesting that they might stimulate RAW264.7 cells through the activation of NF-ƙB and MAPKs pathways. Furthermore, the structural details of WBP-F were studied by GC-MS and NMR spectrum, which confirms that the main backbone consists of 4-α-D-linked glucopyranosyl residues with branching points at C-6. PRACTICAL APPLICATIONS: Wheat bran is a potential source of health-promoting compounds. It has been reported that polysaccharides of wheat bran containing numerous beneficial activities. In this study, the wheat bran polysaccharide was extracted, fractionated and investigated their immunostimulatory activities. The results found in this study revealed that the purified polysaccharide from wheat bran potentially enhanced the RAW264.7 cells activation. Hence, these polysaccharides could be utilized as a potent immunity-enhancing agent in food and pharmaceutical industries.

The concentration of L-cysteine (Cys), a sulfur-containing amino acid, acts as an indicator and biomarker for various diseases in humans. Therefore, the identification and detection of abnormal concentrations of Cys are critically important for determining human health. In this study, excitation-dependent multiple emission nitrogen and sulfur co-doped carbon dots (NS-CDs) are synthesized using a one-pot hydrothermal method. The prepared NS-CDs exhibit a small particle size, good optical properties with high quantum yield, excellent stability, and excitation-dependent photoluminescence (PL) property. The synthesized NS-CDs display a narrow diameter ranging from 3 to 7 nm with a relatively higher quantum yield (QY) up to 11.4%. Under optimal conditions, these NS-CDs show good selectivity for Cys over other biologically relevant species and even other similar (di)thiols (GSH/DTT). The synthesized NS-CDs show excellent selectivity and sensitivity to Cys, with a low detection limit of 23 nM and a linear detection range from 0 to 10 μM. The NS-CDs and NS-CDs/Cys are used for cell imaging, showing low toxicity to HCT116 cells and exhibits green fluorescence when observed by confocal microscopy. Furthermore, the controllable and strong photoluminescent emission properties of the NS-CDs and NS-CDs/Cys are visualized as green photoluminescent ink under UV light illumination. The present study is an attractive and innovative perception into the biomedical applications of NS-CDs with controllable photoluminescence.

The polysaccharide isolated from F. gummosa (FGP) was found homogenous with a weight average molecular weight (Mw) of 50.0 × 103 g/mol and radius of gyration (Rg) of 105.3 nm. The FGP was an arabinogalactan with a backbone formed of →6)-β-Galp-1→ residues having random branching points at C-3 extended with either β-Galp-(1→3)-β-Galp-(1→ or α-Araf-(1→ side chain residues. FGP exhibited proliferative effect on RAW264.7 cells and induced macrophages to exert proinflammatory response releasing NO and up-regulating the transcription of cytokines including TNF-α, IL-1β, IL-6 and IL-12. The FGP induced NK-92 cells to up-regulate the expressions of TNF-α, IFN-γ, granzyme-B, perforin, NKG2D and FasL. The presence of p-NF- κB, p-ERK, p-JNK and p-p38 in RAW264.7 and NK-92 cells indicated their activation through NF-κB and MAPKs signaling pathways. These findings suggested that polysaccharides from F. gummosa are potent in boosting immune system and thus may be considered for further studies of biomedical applications.

Polysaccharides from Nizamuddinia zanardinii were extracted using water at elevated temperature and fractionated by a DEAE Sepharose FF column yielding four fractions (F1-F4). Crude and fractions were composed of neutral sugars (50.8–57.4%), proteins (10.8–18.1%), sulfates (7.5–17.3%) and uronic acids (3.5–7.7%). Various levels of galactose (13.4–44.4%), fucose (34.1–40.1%), mannose (14.1–33.2%) and xylose (7.4–15.2%) formed the building blocks of the polysaccharide structures. The weight average molecular weights (Mw) of polysaccharides varied between 40.3 and 1254.4 × 103 g/mol. F3 polysaccharide was the most active fraction stimulating RAW264.7 murine macrophage cells to secrete NO, TNF-α, IL-1β and IL-6, and activating NK cells to release TNF-α, INF-γ, granzyme-B, perforin, NKG2D and FasL through NF-κB and MAPKs signaling pathways. Highly-branched F3 polysaccharide mainly consisted of (1 → 2)-Fucp, (1 → 2,3)-Manp, (1 → 3)-Galp, (1 → 2)-Manp, (1 → 3)-Manp, (1 → 2,3,4)-Manp and (1 → 2,3,6)-Manp residues with great amount of (→1)-Fucp and (→1)-Xylp. Sulfates substituted at C-2 of fucose and galactose residues. Overall, fucoidan from N. zanardinii showed immense potency in boosting immune system through macrophages and NK cells activations and therefore suitable for further exploration in immune-mediated biomedical applications.

Polysaccharides were extracted from Schizophyllum commune (a common mushroom) and their structural and immune-enhancing properties were investigated. Crude and fractions (F1 and F2) were composed of sugars (50.3-82.8%), proteins (1.46-20.1%), and sulfates (1.33-7.01%). Monosaccharide compositions of Cr and F1 were mainly composed of glucose (75.5% and 88.2%) with small amounts of mannose, galactose and xylose whereas the F2 was mainly composed of manose (55.2%) with minor amounts of galactose, glucose, and xylose. Their immune-enhancing activities were tested using RAW264.7 cells. Proliferation activity of RAW264.7 cells was over 100% after treatment with these polysaccharides. In addition, RAW264.7 cells produced large amounts of nitric oxide and various cytokines by up-regulating mRNA expression levels and the activation of nuclear factor-kappa (NF-κB) and mitogen-activated protein kinase (MAPK) after treatment with these polysaccharides. In addition, RAW264.7 cells were activated mainly through CR-3 and TLR-4 receptors. The backbone of F2 with excellent immune-enhancing activity was mainly linked by (1→3)-linked-mannopyranosyl and (1→2,3)-linked-mannopyranosyl residues.

Water-soluble polysaccharides isolated from the rhizome of Polygonatum sibiricum and fractionated using ion-exchange chromatography were investigated to determine their structure and immunostimulating activity. Crude and fractions (F1 and F2) consisted of carbohydrates (85.1~88.3%) with proteins (4.51~11.9%) and uronic acid (1.79~7.47%), and included different levels of mannose (62.3~76.3%), glucose (15.2~20.3%), galactose (4.35~15.3%), and arabinose (4.00~7.65%). The crude contained two peaks with molecular weights (Mw) of 151×103 and 31.8×103, but F1 and F2 exhibited one major peak with Mw of 103×103 and 628×103, respectively. Little immunostimulatory activity was observed by the crude; however, F1 and F2 significantly activated RAW264.7 cells to release nitric oxide and various cytokines, suggesting they were potent immunostimulators. The backbone of the most immunostimulating fraction (F1) was (1→4)-manno- and (1→4)-gluco-pyranosyl residues with galactose and glucose attached to O-6 of manno-pyranoside.

Uridine (UdN) is a pyrimidine nucleoside drug that is widely applied in the pharmaceutical industry. The solubility and biological activity of UdN have been enhanced by the formation of inclusion complexes with β-cyclodextrin derivatives (β-CDs), namely, hydroxypropyl-β-cyclodextrin (HPβ-CD) and sulfobutyl-ether-β-cyclodextrin (SBEβ-CD). Optical spectroscopy studies suggested the formation of 1:1 inclusion complexes between UdN and the β-CDs at 303 K, as determined from the Benesi–Hildebrand plot. The solid complexes of UdN and the β-CDs were prepared and characterized by various spectroscopic techniques, and the results indicated the inclusion of UdN in the β-CD cavity. The energetically favored binding interaction of UdN with the β-CDs was confirmed by molecular modeling studies. In addition, the investigations on the antibiofilm and antioxidant activities indicated that the β-CD/UdN complexes exhibited better fungicidal, cytotoxic, and cellular uptake activities than UdN.

Highly selective and rapid sensing of adenosine (AdN) based on novel photoluminescent vanadium nanoclusters (VNCs) anchored on molybdenum disulfide nanosheets (MoS2-NS) are reported for the first time. The remarkably photoluminescent VNCs features excellent water solubility, ultra-small size, and bright photoluminescence. The VNCs on the MoS2-NS (MoS2-NS/VNCs) are well dispersed in aqueous solution and features a remarkable increase in bandgap energy (2.67 eV) compared to MoS2-NS (2.10 eV). The photoluminescence of VNCs was quenched by MoS2-NS via photoluminescence resonance energy transfer (PRET) mechanism. Furthermore, MoS2-NS/VNCs exhibit high selectivity and sensitivity toward AdN over other AdN analogues, biomolecules, and metal ions. Consequently, the absorption spectral maxima appeared at 650 nm and emission significantly enhanced in intensity at 525 nm. Interestingly, the stronger binding of AdN with MoS2-NS/VNCs was fast with nearly 65.7 % photoluminescence restored in less than 5 min. The PL lifetime of MoS2-NS/VNCs (τ1 = 8.20 ns, τ2 = 0.68 ns) increased (τ1 = 10.48 ns, τ2 = 0.79 ns) in the presence of AdN. The observed limit of detection was 29 pM. This VNCs sensor system can be constructed as XNOR logic gate with MoS2 and AdN as chemical inputs by examining the mode of emission. Finally, this probe was used to detect AdN in live cells and human serum samples with satisfactory results.

The aim of the present study was to evaluate the effect of water-soluble polysaccharides from Cuminum cyminum to induce inflammatory response in immune cells and understand their underlying mechanisms. Weight average molecular weight (Mw) of polysaccharides varied between 191.4–512.2 × 103 g/mol. Polysaccharides induced RAW264.7 cells to release nitric oxide and express TNF-α, IL-1β, IL-6 and IL-12 inflammatory cytokines. Polysaccharides activated NK-92 cells to produce TNF-α, IFN-γ, perforin, granzyme B, NKG2D and FasL. Activations of RAW264.7 and NK-92 cells were through NF-κB and MAPKs signal pathways indicated by the presence of phosphorylated NF-κB, ERK, JNK and p38 proteins. The polysaccharide structure was mainly constituted of →4)-Galp-(1→, →3)-Galp-(1→, →2)-Arap-(1→ and →2)-Arap-(1→ glycosidic linkages. Overall results suggested that polysaccharides from C. cyminum possessing lower MW and greater expanded conformation more effectively stimulate RAW264.7 and NK-92 cells and thus could be considered for further studies on their biomedical applications.

The water-soluble crude polysaccharides, extracted from the rhizome of Smilax glabra, were fractionated using an anion exchange chromatography, yielding two fractions, F1 and F2. The crude and fractions (F1 and F2) mainly consisted of carbohydrates (66.7%–91.1%), proteins (7.30%–23.9%) and minor amount of sulfates (1.60%–9.40%). Glucose was the major monosaccharide unit of the polysaccharides with different levels of sugar constituents including galactose, arabinose, rhamnose and mannose. The molecular weight (Mw) of crude and fractions ranged from 32,102–6.3 × 103 g/mol. The crude and fractions could stimulate RAW264.7 cells to release nitric oxide and cytokines via up-regulation of their mRNA expression by the activation of NF-κB and MAPKs pathways. The related pattern recognition receptors (PRRs) on the surface of the cells appeared to be TLR2 and CR3. The GC–MS analysis revealed that the main backbone of the most immune-enhancing F2 was (1 → 4)-linked glucose and galactose chain with minor linkages of (1 → 6)-galactose, (1 → 3)-mannose, (1 → 2)-rhamnose and (1 → 5)-arabinose with some branches at C-3 and C-4 rhamnose, or C-6 galactose.