In vitro antioxidant and antibacterial activity of sulfated polysaccharides isolated from Spatoglossum asperum

Sulfated galactan from Halymenia dilatata enhance the antioxidant properties and prevents Aeromonas hydrophila infection in tilapia fish: In vitro and in vivo study

The structural characterization and pharmaceutical perspective of sulfated galactan from Halymenia dilatata (Hd-SG) were reported in this study. The Hd-SG consists of carbohydrate (58.5 ± 0.9%), sulfate (28.7 ± 0.9%) and protein (2.7 ± 0.2%). The existence of carbon (28.14%), hydrogen (5.50%), nitrogen (0.51%) and sulfur (8.26%) was confirmed in CHNS analysis. The Hd-SG was mainly comprising of galactose and mannose connected by (1 → 4)-glycosidic linkages, and it shows the molecular weight of 900.9 × 103 g/mol in high-performance size exclusion chromatography (HPSEC). The Hd-SG exhibited the dose depended on antioxidant activities. The in vitro and in vivo studies proved the antibacterial efficacy of Hd-SG against Aeromonas hydrophila. The pre-treated Oreochromis fish with Hd-SG (2.0 g/0.1 kg of feed) showed the highest survival, antioxidant, and improved histological changes than the fish infected with A. hydrophila alone. These results concluded that the isolated Hd-SG has extensive therapeutic properties, and it can be used as preventive medicine.

Human Keratinocyte UVB-Protective Effects of a Low Molecular Weight Fucoidan from Sargassum horneri Purified by Step Gradient Ethanol Precipitation

Ultraviolet B (UVB) radiation-induced oxidative skin cell damage is a major cause of photoaging. In the present study, a low molecular weight fucoidan fraction (SHC4) was obtained from Sargassum horneri by Celluclast-assisted extraction, followed by step gradient ethanol precipitation. The protective effect of SHC4 was investigated in human keratinocytes against UVB-induced oxidative stress. The purified fucoidan was characterized by Fourier-transform infrared spectroscopy (FTIR), ¹H nuclear magnetic resonance (NMR), agarose gel-based molecular weight analysis and monosaccharide composition analysis. SHC4 had a mean molecular weight of 60 kDa, with 37.43% fucose and 28.01 ± 0.50% sulfate content. The structure was mainly composed of α-L-Fucp-(1→4) linked fucose units. SHC4 treatment dose-dependently reduced intracellular reactive oxygen species (ROS) levels and increased the cell viability of UVB exposed HaCaT keratinocytes. Moreover, SHC4 dose-dependently inhibited UVB-induced apoptotic body formation, sub-G₁ accumulation of cells and DNA damage. Inhibition of apoptosis was mediated via the mitochondria-mediated pathway, re-establishing the loss of mitochondrial membrane potential. The UVB protective effect of SHC4 was facilitated by enhancing intracellular antioxidant defense via nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling. Further studies may promote the use of SHC4 as an active ingredient in cosmetics and nutricosmetics.

Gastric protective activities of fucoidan from brown alga Kjellmaniella crassifolia through the NF-κB signaling pathway

Fucoidan has been reported to have abundant biological activities. The objective of the present study was to detect the protective effects of fucoidan from Kjellmaniella crassifolia (KF) newly cultured in Dalian, North of China on aspirin-induced gastric ulcers of the Wistar rat model. The present study showed that inflammatory cytokines tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6 and IL-10 were effectively regulated in rats pretreated with KF. Superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities increased significantly in the KF pretreated groups, while the levels of maleic dialdehyde (MDA) decreased. The findings obtained by RT-PCR and western blotting indicated that KF could suppress aspirin-induced NF-κB activation via stabilization of IκB-α and thereby induced the downregulation of COX-2 and iNOS. It was demonstrated that KF exerted positive gastric protective effects via suppression of the inflammatory response and oxidative stress, and the mechanism of KF appeared to mediate the NF-κB signaling pathway.

The Antioxidant Activity of Polysaccharides Derived from Marine Organisms: An Overview

Marine-derived antioxidant polysaccharides have aroused extensive attention because of their potential nutritional and therapeutic benefits. However, the comprehensive comparison of identified marine-derived antioxidant polysaccharides is still inaccessible, which would facilitate the discovery of more efficient antioxidants from marine organisms. Thus, this review summarizes the sources, chemical composition, structural characteristics, and antioxidant capacity of marine antioxidant polysaccharides, as well as their protective in vivo effects mediated by antioxidative stress reported in the last few years (2013-2019), and especially highlights the dominant role of marine algae as antioxidant polysaccharide source. In addition, the relationships between the chemical composition and structural characteristics of marine antioxidant polysaccharides with their antioxidant capacity were also discussed. The antioxidant activity was found to be determined by multiple factors, including molecular weight, monosaccharide composition, sulfate position and its degree.

Unravelling property of polysaccharides from Sargassum sp. as an anti-wrinkle and skin whitening property

In recent years, the natural ingredients are in high demand in formulating the cosmetic products. Seaweed polysaccharides signify the attractive natural ingredient with a wide range of functional properties that are expected for cosmeceutical formulations. The present work aimed to study the skin protection ability of polysaccharides extracted from Sargassum vachellianum (SvP), Sargassum horneri (ShoP) and Sargassum hemiphyllum (SheP). The extracted crude polysaccharides were characterized by HPLC and FTIR, which revealed that the polysaccharides are fucose-containing sulfated polysaccharides. Skin whitening and anti-wrinkling activity were analyzed by the ability to inhibit tyrosinase and elastase. The results revealed that the ShoP showed maximum tyrosinase inhibition (64.72 ± 0.46%) and SvP exhibited considerable elastase inhibition (30.12 ± 0.33%). The maximum moisture absorption (79.7 ± 0.62%) and retention (68.99 ± 0.64%) ability were observed in ShoP. The antioxidant activity was estimated by DPPH, superoxide radical scavenging, reducing power and total antioxidant activity. All the tested polysaccharides showed antioxidant activity in a dose-dependent manner, among them ShoP exhibited maximum total antioxidant (80.93 ± 0.17%) and superoxide radical scavenging activity (67.4 ± 0.42%) whereas SheP showed maximum DPPH radical scavenging activity (74.56 ± 0.10%). Therefore, the present study indicates the potential of polysaccharides, ShoP, SvP and SheP as a promising cosmetic ingredient in cosmeceuticals.

Fucoidan isolated from Padina commersonii inhibit LPS-induced inflammation in macrophages blocking TLR/NF-κB signal pathway

Brown seaweeds are well-known source of bioactive compounds, which are producing a variety of secondary metabolites with promising bioactive properties. Traditionally, seaweeds used as ingredients in medicine for many centuries in Asian countries. However, the protective mechanisms of many metabolites found in seaweeds are remains to be determined. Thus, applications of seaweeds are limited because of poor understanding of their structural features and mechanisms responsible for their bioactive properties. In the present study, anti-inflammatory properties of fucoidan isolated from the brown seaweed Padina commersonii (PCF) was evaluated against LPS-activated RAW 264.7 macrophages. PCF was characterized using NMR, FT-IR, and HPAE-PAD spectrum (for mono sugar composition). It was observed that PCF is rich in fucose and sulfate as well as a similar structure to the commercial fucoidan. Western blots and RT-qPCR analysis were used to determine the protective effects of PCF after LPS challenge using RAW 264.7 macrophages. According to the results, PCF significantly down-regulated LPS-activated mRNA and protein expression levels of TLR2, TLR4, and MyD88 which are known inducers/activators of NF-κB transcriptional factors. The results, obtained from this study demonstrated PCF has a potential to inhibit LPS-induced inflammatory responses via blocking TLR/MyD88/ NF-κB signal transduction.

Pharmacologic Application Potentials of Sulfated Polysaccharide from Marine Algae

With the advent of exploration in finding new sources for treating different diseases, one possible natural source is from marine algae. Having an array of potential benefits, researchers are interested in the components which comprise one of these activities. This can lead to the isolation of active compounds with biological activities, such as antioxidation of free radicals, anti-inflammation, antiproliferation of cancer cells, and anticoagulant to name a few. One of the compounds that are isolated from marine algae are sulfated polysaccharides (SPs). SPs are complex heterogenous natural polymers with an abundance found in different species of marine algae. Marine algae are known to be one of the most important sources of SPs, and depending on the species, its chemical structure varies. This variety has important physical and chemical components and functions which has gained the attention of researchers as this contributes to the many facets of its pharmacologic activity. In this review, recent pharmacologic application potentials and updates on the use of SPs from marine algae are discussed.

Structural characterization and immunostimulatory activity of a novel polysaccharide from green alga Caulerpa racemosa var peltata

A novel water-soluble polysaccharide (named CRVP-1) was successfully obtained from Caulerpa racemosa var peltata by hot-water extraction, ethanol precipitation, and column chromatography. The structure of CRVP-1 was characterized by HPGPC, HPAEC-PAD, FT-IR, GC-MS and NMR. The structural analysis indicated that CRVP-1 possessed a sulfate content of 25.8%±0.7% and was a heteropolysaccharide with an average molecular weight of 29.68kDa, and composed of mannose, galactose, glucose, galacturonic acid, and glucuronic acid with rates of 92.1%, 2.9%, 1.8%, 1.7% and 1.2%, respectively, owning a backbone structure of (1→6)-linked α-D-Manp residues with (1→4)-linked α-D-Manp and (1→2)-linked α-D-Manp residues and side chain that was consisted of (1→4)-linked β-D-Galp residues. The immunostimulatory assay revealed that CRVP-1 had significant effects on the proliferation of macrophage, production of NO and secretion of cytokines (TNF-α, IL-1β and IL-6). These findings provide a scientific basis for further utilization of polysaccharides from C. racemosa var peltata.

Antibacterial efficacy of a fucoidan fraction (Fu-F2) extracted from Sargassum polycystum

In this study therapeutic potential of fucoidan fraction-2 (Fu-F2) isolated from Sargassum polycystum was evaluated for the development of antibacterial agent against the human and animal pathogenic bacteria by in vitro and in vivo analysis. The Fu-F2 contained 51.12 ± 0.86% of total sugar and 20.41 ± 0.91% of sulfate. The structural characterization of Fu-F2 was performed by HPLC, FTIR and NMR analysis and reported in our earlier study. The in vitro antibacterial assays such as MIC, MBC, killing kinetics, disk diffusion, protein leakage, ROS and confocal laser scanning microscopy demonstrate that Fu-F2 possesses the highest antibacterial activity against the tested pathogens. Among the tested pathogens, the highest antibacterial activity (21 ± 1.0 mm) was recorded at the concentration of 50 μg/ml against Pseudomonas aeruginosa and the lowest activity (16 ± 0.53 mm) was registered against Staphylococcus aureus. In the in vivo analysis, the pre-treatment group with Fu-F2 at the concentration of 15 mg/0.1 kg through feed exhibited the highest survival (83.4%) and antioxidant activities (p < 0.05) than the fish infected with pathogen. Thus, the present findings suggest that the Fu-F2 of S. polycystum encompasses significant antibacterial properties and that can be used as a therapeutic agent for controlling the bacterial disease.

Attenuation of oxidative stress induced mitochondrial dysfunction and cytotoxicity in fibroblast cells by sulfated polysaccharide from Padina gymnospora

In this present study, isolation, characterization and protective effect of sulfated polysaccharide (SP) isolated from the brown algae Padina gymnospora was investigated. SP was isolated and characterized through FT-IR, 1H NMR, TGA, GC-MS and CHN analysis. The molecular weight of SP was found to be 16 kDa. The isolated SP contains 29.4 ± 0.35% of sulfate, 27 ± 0.11% of fucose, 0.05 ± 0.12% of protein, respectively. Furthermore, SP exhibits its excellent radical scavenging effects were evaluated by DPPH, ABTS radical scavenging and reducing power assays. Moreover, pretreatment with SP significantly mitigates H2O2 induced cytotoxicity in L-929 cells in a dose dependent manner. Furthermore, SP pretreatment ameliorates oxidative stress induced apoptosis and DNA damage, alleviates the generation of intracellular reactive oxygen species (ROS) and restores mitochondrial membrane potential (MMP) in L-929 cells through its antioxidant potential. Together, these results suggest that SP can be exploited as a natural antioxidant in the food and pharmaceutical industries.

Investigation of antioxidant and anticancer potential of fucoidan from Sargassum polycystum

The present study was aimed to evaluate the antioxidant and anticancer potential of fucoidan isolated from Sargassum polycystum. The isolated fucoidan was successfully purified by DEAE cellulose-ion exchange chromatography and dialysis. Totally four active fractions (F1-F4) were collected and explored its chemical constitution by calorimetric assays. Among them, fraction 2 (F2) showed the higher yield percentage, fucose and sulphate content. Further, monosaccharide composition, structural and functional properties of the F2 was analyzed by HPLC, FTIR and NMR. F2 shows highest DPPH radical scavenging activity (55.94 ± 0.69%), reducing power (0.33 absorbance rate), hydrogen peroxide scavenging activity (71.76 ± 2.14%) and nitric oxide radical scavenging activity (51.81 ± 1.04%) at 1000 μg/ml. The cell viability of MCF-7 and HCT-15 cell lines was proportionate to the concentration of F2 with an estimated IC50 was 20 and 50 μg/ml respectively. The fluorescence and confocal laser scanning microscopic analysis demonstrated the apoptotic morphological changes and cell mediated death in F2 treated cancer cells. Higher amount of LDH release was found in the F2 treated cancer cells than the control group. Thus, the present finding proved that the isolated F2 encompasses significant antioxidant and anticancer property.

Extraction Optimization, Characterization, and Bioactivities of Polysaccharides from Pinelliae Rhizoma Praeparatum Cum Alumine Employing Ultrasound-Assisted Extraction

In this study, the ultrasound-assisted extraction of polysaccharides (PSA) from Pinelliae Rhizoma Praeparatum Cum Alumine (PRPCA) was optimized by response surface methodology (RSM). The structural characteristics of PSA were analyzed by UV-vis spectroscopy, infrared spectroscopy, scanning electron microscopy, high performance gel permeation chromatography and high performance liquid chromatography, respectively. In addition, antioxidant and antimicrobial activities of PSA were studied by different in vitro assays. Results indicated that the optimal extraction conditions were as follows: the ratio of water to raw of 30 mL/g, extraction time of 46.50 min, ultrasonic temperature of 72.00 °C, and ultrasonic power of 230 W. Under these conditions, the obtained PSA yield (13.21 ± 0.37%) was closely agreed with the predicted yield by the model. The average molecular weights of the PSA were estimated to be 5.34 × 10³ and 6.27 × 10⁵ Da. Monosaccharide composition analysis indicated that PSA consisted of mannose, galactose uronic acid, glucose, galactose, arabinose with a molar ratio of 1.83:0.55:75.75:1.94:0.45. Furthermore, PSA exhibited moderate antioxidant and antibacterial activities in vitro. Collectively, this study provides a promising strategy to obtain bioactive polysaccharides from processed products of herbal medicines.