Immunomodulation by xylan and carrageenan-type polysaccharides from red seaweeds: Anti-inflammatory, wound healing, cytoprotective, and anticoagulant activities.

The immunomodulatory properties of the polysaccharides (carrageenan, xylan) from Chondrus crispus (CC), Ahnfeltiopsis devoniensis (AD), Sarcodiotheca gaudichaudii (SG) and Palmaria palmata (PP) algal species were studied. Using RAW264.7 macrophages, we investigated the proliferation and migration capacity of different extracts along with their immunomodulatory activities, including nitric oxide (NO) production, phagocytosis, and secretion of pro-inflammatory cytokines. Polysaccharides from C. crispus and S. gaudichaudii effectively mitigated inflammation and improved scratch-wound healing. Polysaccharide fractions extracted under cold conditions (25 °C), including CC-1A, SG-1A and SG-1B stimulated cell proliferation, while fractions extracted under hot conditions (95 °C), including CC-3A, CC-2B and A. devoniensis (AD-3A), inhibited cell proliferation after 48 h. Furthermore, RAW264.7 cells treated with the fractions CC-3A, AD-1A, and SG-2A significantly reduced LPS-stimulated NO secretion over 24 h. Phagocytosis was significantly improved by treatment with C. crispus (CC-2B, CC-3B) and A. devoniensis (AD-3A) fractions. RAW264.7 cells treated with the CC-2A and SG-1A fractions showed elevated TGF-ß1 expression without affecting TNF-α expression at 24 h. Polysaccharide fractions of A. devoniensis (ι/κ hybrid carrageenan; AD-2A, AD-3A) showed the highest anti-coagulation activity. CC-2A and SG-1A fractions enhanced various bioactivities, suggesting they are candidates for skin-health applications. The carrageenan fractions (CC-3A: λ-, µ-carrageenan, SG-2A: ν-, ι-carrageenan) tested herein showed great potential for developing anti-inflammatory and upscaled skin-health applications.

Preparation of Thermoplastic Cellulose Esters in [mTBNH][OAC] Ionic Liquid by Transesterification Reaction.

The transesterification of cellulose with vinyl esters in ionic liquid media is suggested as a prospective environmentally friendly alternative to conventional esterification. In this study, various long-chain cellulose esters (laurate, myristate, palmitate, and stearate) with a degree of substitution (DS) up to 1.8 have been synthesized in novel distillable ionic liquid, [mTBNH][OAC]. This IL has high dissolving power towards cellulose, which can improve homogeneous transesterification. Additionally, [mTBNH][OAC] has durability towards recycling and can be regenerated and re-used again for the next cycles of esterification. DMSO is used as a co-solvent because of its ability to speed up mass transport due to lower solvent viscosity. The optimization of the reaction parameters, such as co-solvent content, temperature (20-80 °C), reaction time (1-5 h), and a molar ratio of reactants (1-5 eq. AGU) is reported. It was found that within studied reaction conditions, DS increases with increasing reaction time, temperature, and added vinyl esters. Structure analysis using FTIR, 1H, and 13C NMR after acylation revealed the introduction of the alkyl chains into cellulose for all studied samples. The results also suggested that the substitution order of the OH group is C7-O6 > C7-O2 > C7-O3. Unique, complex thermal and rheological investigation of the cellulose esters shows the growth of an amorphous phase upon the degree of substitution. At the same time, the homogeneous substitution of cellulose with acyl chains increases the melt viscosity of a material. Internal plasticization in cellulose esters was found to be the mechanism for the melt processing of the material. Long-chain cellulose esters show the potential to replace commonly used externally plasticized cellulose derivatives.

Biochemical Characteristics and Potential Biomedical Applications of Hydrolyzed Carrageenans.

Seaweed contains a variety of bioactive compounds; the most abundant of them are polysaccharides, which have significant biological and chemical importance. Although algal polysaccharides, especially the sulfated polysaccharides, have great potential in the pharmaceutical, medical and cosmeceutical sectors, the large molecular size often limits their industrial applications. The current study aims to determine the bioactivities of degraded red algal polysaccharides by several in vitro experiments. The molecular weight was determined by size-exclusion chromatography (SEC), and the structure was confirmed by FTIR and NMR. In comparison to the original furcellaran, the furcellaran with lower molecular weight had higher OH scavenging activities. The reduction in molecular weight of the sulfated polysaccharides resulted in a significant decrease in anticoagulant activities. Tyrosinase inhibition improved 2.5 times for hydrolyzed furcellaran. The alamarBlue assay was used to determine the effects of different Mw of furcellaran, κ-carrageenan and ι-carrageenan on the cell viability of RAW264.7, HDF and HaCaT cell lines. It was found that hydrolyzed κ-carrageenan and ι-carrageenan enhanced cell proliferation and improved wound healing, whereas hydrolyzed furcellaran did not affect cell proliferation in any of the cell lines. Nitric oxide (NO) production decreased sequentially as the Mw of the polysaccharides decreased, which indicates that hydrolyzed κ-Carrageenan, ι-carrageenan and furcellaran have the potential to treat inflammatory disease. These findings suggested that the bioactivities of polysaccharides were highly dependent on their Mw, and the hydrolyzed carrageenans could be used in new drug development as well as cosmeceutical applications.

A novel therapeutic effect of mannitol-rich extract from the brown seaweed Sargassum ilicifolium using in vitro and in vivo models.

BACKGROUND: Wound healing is an active, complex, integrated series of cellular, physiological, and biochemical changes initiated by the stimulus of injury in a tissue. The present study was performed to investigate the potential wound healing abilities of Sargassum ilicifolium crude extracts (CE) that were characterized by 1H NMR and FTIR Spectrometric measurements. MATERIALS AND METHODS: Seaweed samples were collected from southern coastal sites of Sri Lanka. To determine the cytotoxicity and proliferation of S. ilicifolium CE were used for the MTT and alamarBlue assays respectively. The scratch and exclusion wound models were used to HaCaT and HDF cells to assess the cell proliferation and migration. RAW 264.7 cells (macrophages) were used to evaluate Nitric Oxide (NO) production and phagocytosis activities. Moreover, Fifteen, 8-week-old, female, New Zealand rabbits were selected and divided into five groups: excision skin wounds (10.40 ± 0.60 mm) were induced in groups I, II, and III. Rabbits in groups I and IV were given S. ilicifolium CE (orally, 100 mg/kg day, two weeks), whereas groups II and V were given equal amounts of distilled water. Wound healing properties were measured and wound tissue samples were collated, formalin-fixed, wax-embedded, stained (Hematoxylin and Eosin; Van Gieson) and examined for the healing process. RESULTS: Anti-inflammatory and wound healing activities were observed in RAW 264.7, HDF and HaCaT cells treated with S. ilicifolium aqueous extracts when compared to the control groups. S. ilicifolium extracts concentration 8 - 4 µg/µL, (P<0.05) had remarkable the highest proliferative and migratory effects on RAW 264.7, HDF and HaCaT cells when compared with the control. RAW 264.7 cell proliferation and/or migration were higher in S. ilicifolium extracts (4 µg/µL, 232.8 ± 10.07%) compared with the control (100 %). Scratch wound healing were remarkably enhanced in 24 h, 48 h (P<0.05) when treated with S. ilicifolium on HaCaT cells. Rabbits treated with the CE of S. ilicifolium showed a significantly increased wound healing activities (P<0.05) within three days with a close wound area of 57.21 ± 0.77 % compared with control group (26.63 ± 1.09 %). Histopathology, aspartate aminotransferase and alanine aminotransferase levels evidenced no toxic effects on seaweed treated groups. Histopathological results also revealed that the healing process was significantly faster in the rabbit groups which were as treated with CE of S. ilicifolium orally with the evidence of enhanced early granulation tissue (connective tissue and angiogenesis) and significant epithelization compared to the control. CONCLUSIONS: Cell proliferation and migration are significantly faster when treated with S. ilicifolium aqueous extracts. Moreover, there are no toxic effect of S. ilicifolium aqueous extracts on RAW 264.7, HDF and HaCaT cell lines. In this study, it is revealed that S. ilicifolium has potential remedial agent; D-Mannitol for skin wound healing properties that by promote keratinocyte and fibroblast proliferation and migration. These findings show that S. ilicifolium have promising wound healing properties.

Small organic molecules containing amorphous calcium phosphate: synthesis, characterization and transformation.

As the primary solid phase, amorphous calcium phosphate (ACP) is a pivotal precursor in cellular biomineralization. The intrinsic interplay between ACP and Howard factor underscores the significance of understanding their association for advancing biomimetic ACP development. While organic compounds play established roles in biomineralization, this study presents the synthesis of ACP with naturally occurring organic compounds (ascorbate, glutamate, and itaconate) ubiquitously found in mitochondria and vital for bone remodeling and healing. The developed ACP with organic compounds was meticulously characterized using XRD, FTIR, and solid-state 13C and 31P NMR. The morphological analysis revealed the characteristic spherical morphology with particle size close to 20 nm of all synthesized ACP variants. Notably, the type of organic compound strongly influences true density, specific surface area, particle size, and transformation. The in vitro analysis was performed with MC3T3-E1 cells, indicating the highest cell viability with ACP_ASC (ascorbate), followed by ACP_ITA (itaconate). The lowest cell viability was observed with 10 %w/v of ACP_GLU (glutamate); however, 1 %w/v of ACP_GLU was cytocompatible. Further, the effect of small organic molecules on the transformation of ACP to low crystalline apatite (Ap) was examined in Milli-Q® water, PBS, and α-MEM.

Crystal structure of 3-de-oxy-3-nitro-methyl-1,2;5,6-di-O-iso-propyl-idene-α-d-allo-furan-ose.

The title compound, C13H21NO7 {systematic name: (3aR,5S,6R,6aR)-5-[(R)-2,2-dimethyl-1,3-dioxolan-4-yl]-2,2-dimethyl-6-(nitro-meth-yl)tetra-hydro-furo[2,3-d][1,3]dioxole}, consists of a substituted 2,2-di-methyl-tetra-hydro-furo[2,3-d][1,3]dioxolane skeleton. The furan-ose ring A adopts a (o)T 4 conformation. The fused dioxolane ring B and the substituent dioxolane ring C also have twisted conformations. There are no strong hydrogen bonds in the crystal structure: only weak C-H⋯O contacts are present, which link the mol-ecules to form a three-dimensional structure.

Crystal structure of 3-C-(N-benzyl-oxy-carbon-yl)amino-methyl-3-de-oxy-1,2:5,6-di-O-iso-propyl-idene-α-d-allo-furan-ose.

The title compound, C21H29NO7 (1) [systematic name: benzyl ({(3aR,5S,6R,6aR)-5-[(R)-2,2-dimethyl-1,3-dioxolan-4-yl]-2,2-di-methyl-tetrahydro-furo[2,3-d][1,3]dioxol-6-yl}meth-yl)carbamate], consists of a substituted 2,2-di-methyl-tetra-hydro-furo[2,3-d][1,3]dioxolane skeleton. The furan-ose ring adopts an envelope conformation close to C 3-exo, where the C atom substituted by the benzyl carbamate group is the flap. The fused dioxolane ring also adopts an envelope conformation, as does the terminal dioxolane ring, with in each case an O atom as the flap. In the crystal, mol-ecules are linked by N-H⋯O and C-H⋯O hydrogen bonds, forming chains propagating along the b-axis direction.

Crystal structure of 3-O-benzyl-4(R)-C-(1-benzyl-1H-1,2,3-triazol-4-yl)-1,2-O-iso-propyl-idene-α-d-erythro-furan-ose.

The title compound, C23H25N3O4, {systematic name: 1-benzyl-4-[(3aR,5R,6R,6aR)-6-benz-yloxy-2,2-di-methyl-tetra-hydro-furo[2,3-d][1,3]dioxol-5-yl]-1H-1,2,3-triazole}, consists of a substituted 2,2-di-methyl-tetra-hydro-furo[2,3-d][1,3]dioxole. The furan-ose ring adopts an envelope conformation close to C 3-exo, where the C atom substituted by the benz-yloxy group is the flap. The fused dioxolane ring also adopts an envelope conformation, with the methyl-ene C atom as the flap. In the crystal, mol-ecules are linked by weak C-H⋯O hydrogen bonds, forming zigzag chains along [010].

{(3aR,5S,6R,6aR)-5-[(R)-1,2-Di-hydroxy-eth-yl]-2,2-di-methyl-tetra-hydro-furo[2,3-d][1,3]dioxol-6-yl}methyl methane-sulfonate.

In the title compound, C11H20O8S, the furan-ose ring has a pseudorotation phase angle equal to 31.3° and assumes a (3) T 4 conformation, with deviations of 0.297 (4) and -0.152 (4) Šfor the corresponding C atoms. The dioxolane ring adopts an envelope conformation. One of the O atoms is at the flap and deviates from the least-squares plane formed by the other four ring atoms by 0.405 (2) Å. The dihedral angle between the planar fragments of the rings is 63.53 (8)°. In the crystal, mol-ecules are associated into sheets perpendiculer to the b axis by means of O-H⋯O hydrogen bonds. A few weak C-H⋯O inter-actions are also observed.

On Moffatt dehydration of glucose-derived nitro alcohols.

Moffatt dehydration of 1,2:5,6-di-O-isopropylidene-α-d-glucofuranose derived nitro alcohols with a mixture of Ac(2)O and DMSO was reinvestigated. It was discovered that, regardless of the absolute configuration at C(3) of the sugar moiety, the dehydration provided exclusively the (3Z)-nitromethylene derivative. Slight modification of the workup conditions (pH⩾8, temperature: 25-30°C) gave exclusively a novel product, (3S)-3-deoxy-3-methylthio-3-C-nitromethyl-1,2:5,6-di-O-isopropylidene-α-d-glucofuranose. The latter was obtained by a Michael addition of thiomethylate anion to the previously reported nitromethylene derivative during the aqueous basic workup at ambient or slightly elevated temperature. The putative mechanism leading to the thiomethylate anion includes Pummerer rearrangement of DMSO and basic hydrolysis of thus formed methylsulfanylmethyl acetate.