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Macroalgae associated bacteria are the major source of polysaccharide hydrolyzing enzymes for efficient bioutilisation of macroalgal biomass. In this study, extracellular porphyranase, PB1 isolated from a macroalgae associated bacterium, Bacillus sp. NIOA284 was purified and characterized for hydrolysis of porphyran into porphyran oligosaccharides. The enzyme, PB1 showed the highest activity at the optimum conditions; the temperature of 35 ºC, pH 7 and 0.4 NaCl with 10 mM CoCl 2. The structural characterization of the enzymatically produced POS using NMR spectroscopy and HRMS spectrometry showed that the enzyme acted on porphyran as β-porphyranase and produced di, tri and tetra saccharides. The bioactive potential of POS was determined based on its radical scavenging and prebiotic activity. Results show that POS exhibited higher antioxidant activity than parent porphyran and fructooligosaccharides. It was also capable to proliferate the beneficial gut bacterium Lactobacillus acidophilus and L. bulgaricus , it recorded a prebiotic activity score equivalent to model prebiotic compound fructooligosaccharides. Results show that the enzymatically produced POS has combined antioxidant and prebiotic activity. This highlights the significance of macroalgae associated bacteria as a source of enzymes capable of hydrolyzing polysaccharides into simple bioactive oligosaccharides for efficient management of chronic disorders caused due to oxidative stress. [Display omitted] • Porphyranase was purified and characterized from a macroalgal associated bacteria. • Oligosaccharides were produced from porphyran through enzymatic hydrolysis. • Porphyran oligosaccharides demonstrated efficient free radical scavenging activity. • Porphyran oligosaccharides exhibited prebiotic activity higher than porphyran. • Bioactive oligosaccharides are efficient for management of oxidative stress. [ABSTRACT FROM AUTHOR]

In this study, the total sugar, protein, 3,6-anhydro galactose and sulfate contents, apparent molecular mass and monosaccharide composition of porphyran isolated from Porphyra yezoensis were analyzed. The pro-angiogenic activity and underlying mechanism of porphyran were further investigated using human umbilical vein endothelial cells (HUVECs) as an in vitro angiogenesis model. The effect of porphyran on the cell viability of HUVECs was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cell adhesion and migration capacity were evaluated using cell adhesion and wound healing assays. The number of lumens formed by HUVECs was analyzed using in vitro tube formation assay. The expression levels of E-cadherin and N-cadherin in HUVECs were analyzed by Western Blotting, and the pro-angiogenic mechanism of porphyran in HUVECs was explored using specific inhibitors of mitogen-activated protein kinases (MAPKs) and vascular endothelial growth factor (VEGF) receptor tyrosine kinase inhibitors. The results showed that porphyran contained (77.48 ± 2.62)% total sugar, (3.24 ± 0.58)% protein, and (20.30 ± 1.06)% 3,6-anhydrogalactose as well as (20.78 ± 3.31)% sulfate groups. The apparent molecular mass of porphyran was 39.81 kDa. Porphyran was mainly composed of galactose, 3,6-anhydrogalactose and sulfate groups, suggesting it to be a sulfated galactan. Furthermore, porphyran treatment in the concentration range of 0–200 μg/mL had no significant toxicity no HUVECs, but instead promote cell proliferation, adhesion, migration, and vascular network formation. Further studies demonstrated that porphyran exerted its pro-angiogenic effect primarily by mediating the down-regulation of E-cadherin expression and the up-regulation of N-cadherin expression through the c-Jun N-terminal kinase (JNK) MAPK and VEGF receptor signaling pathways. In conclusion, porphyran has pro-angiogenic potential, which will provide a scientific basis for the development of porphyran as a novel pro-angiogenic factor and the precision nutrition-guided deep processing and high-value utilization of the red seaweed P. yezoensis.

In this study, the effects of a homogenous porphyran from Porphyra haitanensis (PHP) on the intestinal barrier and gut microbiota were investigated. The results showed that oral administration of PHP resulted in a higher luminal moisture content and a lower pH environment for the growth of beneficial bacteria in the colon of mice. PHP significantly increased the production of total short-chain fatty acids during the fermentation process. PHP made the intestinal epithelial cells of mice arrange more tidily and tightly with a significant increase in mucosal thickness. PHP also increased the amount of mucin-producing goblet cells and the expression of mucin in the colon, which maintained the structure and function of the intestinal mucosal barrier. Moreover, PHP up-regulated the expression of tight junctions including ZO-1 and occludin, improving the intestinal physical barrier function. The results of 16S rRNA sequencing showed that PHP regulated the composition of gut microbiota in mice, increasing the richness and diversity of gut microbiota and the ratio of Firmicutes to Bacteroidetes. This study revealed that the intake of PHP is beneficial for the gastrointestinal tract and PHP could be a potential source of prebiotics in the functional food and pharmaceutical industries. [ABSTRACT FROM AUTHOR]

Marine algae produce complex polysaccharides, which can be degraded by marine heterotrophic bacteria utilizing carbohydrate-active enzymes. The red algal polysaccharide porphyran contains the methoxy sugar 6-O-methyl-d-galactose (G6Me). In the degradation of porphyran, oxidative demethylation of this monosaccharide towards d-galactose and formaldehyde occurs, which is catalyzed by a cytochrome P450 monooxygenase and its redox partners. In direct proximity to the genes encoding for the key enzymes of this oxidative demethylation, genes encoding for zinc-dependent alcohol dehydrogenases (ADHs) were identified, which seem to be conserved in porphyran utilizing marine Flavobacteriia. Considering the fact that dehydrogenases could play an auxiliary role in carbohydrate degradation, we aimed to elucidate the physiological role of these marine ADHs. Although our results reveal that the ADHs are not involved in formaldehyde detoxification, a knockout of the ADH gene causes a dramatic growth defect of Zobellia galactanivorans with G6Me as a substrate. This indicates that the ADH is required for G6Me utilization. Complete biochemical characterizations of the ADHs from Formosa agariphila KMM 3901T (FoADH) and Z. galactanivorans DsijT (ZoADH) were performed, and the substrate screening revealed that these enzymes preferentially convert aromatic aldehydes. Additionally, we elucidated the crystal structures of FoADH and ZoADH in complex with NAD+ and showed that the strict substrate specificity of these new auxiliary enzymes is based on a narrow active site. Key points: • Knockout of the ADH-encoding gene revealed its role in 6-O-methyl-D-galactose utilization, suggesting a new auxiliary activity in marine carbohydrate degradation. • Complete enzyme characterization indicated no function in a subsequent reaction of the oxidative demethylation, such as formaldehyde detoxification. • These marine ADHs preferentially convert aromatic compounds, and their strict substrate specificity is based on a narrow active site. [ABSTRACT FROM AUTHOR]

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Nanotechnology has revolutionized the diagnosis, monitoring and treatment of biomedical diseases, in which nanocarriers have greatly improved the targeting and bioavailability of antitumor drugs. The marine natural polysaccharides fucoidan, chitosan, alginate, carrageenan and porphyran have broad-spectrum bioactivities and unique physicochemical properties such as excellent non-toxicity, biocompatibility, biodegradability and reproducibility, which have placed them as a principal focus in the nanocarrier field. Nanocarriers based on different types of marine polysaccharides are distinctive in addressing antitumor therapeutic challenges such as targeting, environmental responsiveness, drug resistance, tissue toxicity, enhancing diagnostic imaging, overcoming the first-pass effect and innovative 3D binding. Additionally, they all share the possibility of relatively easy chemical modification, while their separation into well-defined derivatives provide innovative structure-activity relationship possibilities. Liposomes, nanoparticles and polymer-micelles constructed from them can efficiently deliver drugs such as paclitaxel, gemcitabine, siRNA and others, which are widely used in radiotherapy, chemotherapy, immunotherapy, nucleic acid therapy and photothermal therapy, yet there are still infinite possibilities for innovation and exploration. This article reviews the recent advances and challenges of marine polysaccharide-based delivery systems as oncology drug nanocarriers. [Display omitted] [ABSTRACT FROM AUTHOR]

Cancer poses a significant threat to human health, and monotherapy frequently fails to achieve optimal therapeutic outcomes. Based on this premise, porphyran (PHP), a marine polysaccharide with immunomodulatory function, was used as a framework to coat gold nanorods and construct a novel nanomedicine (PHP-MPBA-GNRs) combining photothermal therapy and immunotherapy. In this design, PHP not only maintained the dispersion stability and photothermal stability of gold nanorods but also could be released under weakly acidic conditions to activate anti-tumor immunity. In vivo studies have shown that PHP-MPBA-GNRs can effectively inhibit tumor cell proliferation and reduce metastasis under near-infrared (NIR) light irradiation. Preliminary mechanistic investigations revealed that PHP-MPBA-GNRs could increase reactive oxygen species (ROS) and induce apoptosis in cancer cells. The PHP in PHP-MPBA-GNRs can also activate dendritic cells and up-regulate the expression of co-stimulatory molecules and antigen-presenting complexes. All biological experiments, including in vivo tests, demonstrated that PHP-MPBA-GNRs achieved a combination of photothermal therapy and immunotherapy for tumors. [Display omitted] [ABSTRACT FROM AUTHOR]

In this study, the effects of a homogenous porphyran from Porphyra haitanensis (PHP) on the intestinal barrier and gut microbiota were investigated. The results showed that oral administration of PHP resulted in a higher luminal moisture content and a lower pH environment for the growth of beneficial bacteria in the colon of mice. PHP significantly increased the production of total short-chain fatty acids during the fermentation process. PHP made the intestinal epithelial cells of mice arrange more tidily and tightly with a significant increase in mucosal thickness. PHP also increased the amount of mucin-producing goblet cells and the expression of mucin in the colon, which maintained the structure and function of the intestinal mucosal barrier. Moreover, PHP up-regulated the expression of tight junctions including ZO-1 and occludin, improving the intestinal physical barrier function. The results of 16S rRNA sequencing showed that PHP regulated the composition of gut microbiota in mice, increasing the richness and diversity of gut microbiota and the ratio of Firmicutes to Bacteroidetes. This study revealed that the intake of PHP is beneficial for the gastrointestinal tract and PHP could be a potential source of prebiotics in the functional food and pharmaceutical industries.

Recent research shows the growing interest in the development of composite edible films (EFs) by using multiple biopolymers for the substantial improvement in the shelf life and quality of food products, via preventing oxidation among other benefits. In the present work, EFs based on chitosan (CS) and porphyran (POR) loaded with ginger essential oil (GEO) have been developed to study the effect of GEO, glycerol (Gly), and POR on the film structure as well as physical and antioxidant properties. Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) results showed the level of crystallinity and electrostatic interactions between CS, POR, Gly, and GEO. It was found that electrostatic interactions between CS and POR and the incorporation of GEO substantially improved barrier, thermal, optical, and mechanical properties and reduced the moisture content, swelling index, and thickness values. The color values of the S5 film altered apparently with a shift towards yellowness. SEM micrographs of the composite CS-POR-GEO film (S5) showed improved morphological attributes such as more uniformity and homogeneous structure than other films (S1–S4). Results obtained from total phenolic content assay suggested the presence of high phenolic components (5.97 ± 0.01) mg of GAE/g in GEO. Further, findings obtained from antioxidant assays revealed that the addition of GEO and POR significantly increased the antioxidant effects of CS films. All these findings suggested that GEO loaded CS-POR based films showed better physical and chemical properties with a significant improvement in antioxidant potential and thus can be used as a potential packaging material in the food industry. [ABSTRACT FROM AUTHOR]

A novel GH16 β-porphyranase gene porl6Z was cloned from marine bacterium Wenyingzhuangia aestuarii 0F219 and expressed in E. coli, and the biochemical properties and hydrolytic patterns of the recombinant protein Porl6Z_Wa were characterized. Porl6Z_Wa showed the maximum activity at 45 °C and pH 6.5 and keep stable at a wide pH range from 4.0 to 9.0. Porl6Z_Wa exhibited a cold-adapted property. Porl6Z_Wa was an endo-acting enzyme. The final products of Porl6Z_Wa were majorly composed of porphyran disaccharides L6S-G, with a minor portion of tetrasac-charides and hexasaccharides which were substituted by agarose moieties and (or) modified by methyl groups. Porl6Z_Wa could be utilized as a promising tool for degradation of porphyran and directional preparation of porphyran disaccharides, which would facilitate the investigation of porphyran polysaccharides. [ABSTRACT FROM AUTHOR]

In this study, dried sheets of nori, shredded and processed thalli of the red alga Pyropia yezoensis, were fermented with either barley, rice or soybean koji. High-performance liquid chromatographic analyses of the lipid extracts of the fermented products indicated that the fermentation of nori with all kinds of tested koji released free fatty acids, including the eicosapentaenoic acid, from ester lipids. We found that approximately half of the eicosapentaenoic acid in nori had been released as the free fatty acid at up to 4 weeks of fermentation at 30 °C and more than 65% at 8 to12 weeks in the fermented products with barley and rice koji. We also demonstrated the degradation of porphyran, a major cell wall polysaccharide of nori, by gel chromatography on Sephacryl S-300 HR of hot water extracts of the fermented products of nori with barley koji. Approximately two-third of porphyran had been degraded to porphyran oligosaccharides up to 6 weeks of fermentation. Fermentation of nori with koji may bring out the potential health-promoting functions of nori. [ABSTRACT FROM AUTHOR]

Ulcerative colitis is a chronic, spontaneous inflammatory bowel disease that primarily affects the colon. This study aimed to explore how Porphyra haitanensis porphyran (PHP) modulates the immune response and the associated mechanisms that alleviate dextran sulphate sodium-induced colitis in mice. Histological assessments via H&E staining and AB-PAS staining revealed that PHP intervention partially restored the number of goblet cells and improved intestinal mucosal function. Immunohistochemical and Western blot analyses of claudin-1, occludin, and MUC-2 demonstrated that PHP could repair the intestinal barrier and reduce colon damage by upregulating the expression of these proteins. PHP intervention was associated with a decrease in pro-inflammatory cytokine expression and an increase in anti-inflammatory cytokine expression. Moreover, the expression of proteins involved in intestinal immune homing, such as CCR-9, CCL-25, MAdCAM-1, and α4β7, was significantly suppressed in response to PHP treatment. Conversely, PHP upregulates the expression of CD40 and TGF-β1, both of these can promote healing and reduce inflammation in the gut lining. This study demonstrates that PHP can ameliorate ulcerative colitis by enhancing the intestinal barrier and modulating immune responses. These findings offer valuable insights into the potential utility of P. haitanensis as a promising natural product for managing ulcerative colitis. • Porphyran (PHP) was extracted and purified from Porphyra haitanensis. • PHP prevents symptoms of DSS-induced colitis in mice. • PHP enhances intestinal barrier function and prevents cell infiltration in mice. • PHP suppresses the level of CCL25/CCR9. • PHP could comprise a promising functional food strategy to alleviate UC symptoms. [ABSTRACT FROM AUTHOR]

The effect of different cations (K+, Ca2+ and Ba2+) on the gel forming properties of sulfated polysaccharides isolated from the red epiphytic alga, Vertebrata lanosa , using a successive cold (25 °C) and hot (95 °C) alkaline extraction process is presented. The elucidation of their monomeric composition using a two-step reductive hydrolysis and structural analyses (1D and 2D NMR) revealed d -galactose (G) linked to 3,6-anhydro- l -galactose (LA) and also sulfated 3,6-anhydro- l -galactose (L6S) as the major monomers with some amounts of glucose, β- d -xylose, 6- O -methyl- d -galactose (G6M), 2- O -methyl- l -anhydrogalactose (LA2M) and l -arabinofuranose. This composition implied the presence of both diads of agaran types, funoran and porphyran in polysaccharides from Vertebrata lanosa. Similar to funorans, their gelation, was highly influenced in the presence of Ba2+ ions compared to other tested salts. 0.2 M of BaCl 2 in the hot extracted fractions recorded storage modulus (Gʹ) to up to ∼80 Pa and increased complex viscosity to 16,000 mPa s compared to the <5 Pa storage modulus from pristine solutions with no added salts. Sulfate amount contained within these fractions ranged up to ∼30% with less than 1 % (gallic acid equivalent, GAE) total phenolic compounds. Some of these fraction, nonetheless, have shown good α-amylase and reactive oxygen species (ROS) inhibition activities thus suggesting a nutraceutical potential of hydrocolloids from this algal species. [Display omitted] • Vertebrata lanosa contains diads of both funoran and porphyran. • α-galactopyranose residues in this polysaccharide are in l -enantiomer forms only. • Polysaccharides from V. lanosa have good α-amylase inhibition activity. • Ba2+ enhances rheological properties of polysaccharides from V. lanosa. [ABSTRACT FROM AUTHOR]

Porphyran is a favorable functional polysaccharide widely distributed in Porphyra. It displays a linear structure majorly constituted by alternating 1,4-linked α- l -galactopyranose-6-sulfate (L6S) and 1,3-linked β- d -galactopyranose (G) units. Carbohydrate-binding modules (CBMs) are desired tools for the investigation and application of polysaccharides, including in situ visualization, on site and specific assay, and functionalization of biomaterials. However, only one porphyran-binding CBM has been hitherto reported, and its structural knowledge is lacking. Herein, a novel CBM16 family domain from a marine bacterium Aquimarina sp. BL5 was discovered and expressed. The recombinant protein AmCBM16 exhibited the desired specificity for porphyran. Bio-layer interferometry assay revealed that the protein binds to porphyran tetrasaccharide (L6S-G) 2 with an association constant of 1.3 × 103 M−1. The structure of AmCBM16 was resolved by the X-ray crystallography, which displays a β-sandwich fold with two antiparallel β-sheets constituted by 10 β-strands. Site-directed mutagenesis analysis demonstrated that the residues Gly-30, Trp-31, Lys-88, Lys-123, Phe-125, and Phe-127 play dominant roles in AmCBM16 binding. This study provides the first structural insights into porphyran-binding CBM. • A novel CBM16 domain was discovered, expressed, and characterized. • Its binding capacity was qualitatively and quantitatively investigated. • The CBM exhibits the desired specificity for porphyran. • Its crystal structure and critical functional residues were determined. • The study provides the first structural insights into porphyran-binding CBM. [ABSTRACT FROM AUTHOR]

Laminaran, porphyran, and ulvan are major seaweed polysaccharides in brown, red, and green algae, respectively. We compared their prebiotic effects using individual microbial fermentability test and in vitro fecal fermentation. The fermentability test showed that these polysaccharides were selectively utilized by Bifidobacteria, Lactobacilli, and Bacteroides (ΔOD580 nm, 0.2–1.0), while no growth of harmful bacteria was observed. In vitro fecal fermentation for 24 h showed growth stimulation effect of laminaran on Bifidobacteria (Δ8.3%/total bacteria) and Bacteroides (Δ13.8%/total bacteria) promoting the production of acetate and propionate. Ulvan exhibited same result on Bifidobacteria (Δ8.5%/total bacteria) and Lactobacillus (Δ6.8%/total bacteria) promoting the production of lactate and acetate; however, porphyran showed little prebiotic effect. Laminaran was fermented slowly compared to fructooligosaccharides and this may permit production of short-chain fatty acids in distal colon. This in vitro study demonstrates that the seaweed polysaccharides tested, particularly laminaran and ulvan, have prebiotic effects on microbiota in human colon.

Porphyran, the major polysaccharide extracted from Porphyra , exhibits tremendous potential for development as functional food or pharmaceutical due to its multiple biological activities. The quantitative analysis of porphyran is important for the quality control in product development. However, the specific quantitative method of porphyran has not been established, and the lack of reference substance makes the quantification more challenging. Here, a common component of porphyran, with high purity, similar molecular weight distribution, sourced from different Porphyra producing areas in China was first prepared by a series of isolation and purification steps, and utilized as the reference substance for porphyran quantification. Subsequently, the porphyran was fully degraded into oligosaccharides by using a β -porphyranase, followed by employing para-hydroxybenzoic acid hydrazide (pHBH) method to detect the content of the generated reducing sugar. The enzyme-pHBH method for porphyran specific quantification was established. Results showed that this method was validated with good linearity, high accuracy and precision, and reliability. Addtionally, NaCl with a concentration below 0.5 %, alcohol under 8 % and other polysaccharide including chitosan, agarose, chondrotin sulfate, alginate, hyaluronic acid and κ-carrageenan did not interfere with this method. This approach is promising for quality control of the porphyran products and offers a feasible strategy for the specific quantification of other polysaccharides. [ABSTRACT FROM AUTHOR]

BACKGROUND: Pyropia yezoensis, rich in porphyran, is a medicine‐edible red alga. In the present study, the physicochemical characteristics, conformational states and antitumor activities of a novel porphyran extracted from the high‐yield algal strain Pyropia yezoensis Chonsoo2 and its two degraded derivatives by gamma irradiation were investigated. RESULTS: Pyropia yezoensis porphyran is a water‐soluble, triple‐helical sulfated hetero‐galactopyranose, named PYP. PYP was degraded by gamma irradiation at 20 kGy and 50 kGy, giving two low molecular weight derivatives comprising PYP‐20 and PYP‐50, respectively. PYP with a higher molecular weight has a solution conformation different from PYP‐20 and PYP‐50. Three porphyrans had no toxicity in normal human liver cells (HL‐7702) and showed antitumor effects on Hep3B, HeLa and MDA‐MB‐231. They had better antitumor against HeLa cells, exhibiting a similar inhibition ratio compared to 5‐fluorouracil, with PYP especially exhibiting a higher inhibition ratio than 5‐fluorouracil. With respect to HeLa cells, the different antitumor activities might be related to porphyran molecular weight and solution conformation. Furthermore, the HeLa cell cycle was blocked in the G2/M phase after PYP treatment, leading to cell proliferation inhibition. The induction of cell cycle arrest was related to the changes in the expression of p21, p53, Cyclin B1 and cyclin‐dependent kinase 1. CONCLUSION: Pyropia yezoensis porphyran, as applied to medicine and functional food, could potentially be used as a non‐toxic natural adjuvant in cancer therapy. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

• Laminaran stimulated the growth of Bifidobacteria and Bacteroides. • Ulvan stimulated the growth of Bifidobacteria and Lactobacilli. • Porphyran showed lower prebiotic effect than laminaran and ulvan. • Laminaran was fermented slowly to give prebiotic effect in the distal colon. Laminaran, porphyran, and ulvan are major seaweed polysaccharides in brown, red, and green algae, respectively. We compared their prebiotic effects using individual microbial fermentability test and in vitro fecal fermentation. The fermentability test showed that these polysaccharides were selectively utilized by Bifidobacteria, Lactobacilli, and Bacteroides (ΔOD 580 nm , 0.2–1.0), while no growth of harmful bacteria was observed. In vitro fecal fermentation for 24 h showed growth stimulation effect of laminaran on Bifidobacteria (Δ8.3%/total bacteria) and Bacteroides (Δ13.8%/total bacteria) promoting the production of acetate and propionate. Ulvan exhibited same result on Bifidobacteria (Δ8.5%/total bacteria) and Lactobacillus (Δ6.8%/total bacteria) promoting the production of lactate and acetate; however, porphyran showed little prebiotic effect. Laminaran was fermented slowly compared to fructooligosaccharides and this may permit production of short-chain fatty acids in distal colon. This in vitro study demonstrates that the seaweed polysaccharides tested, particularly laminaran and ulvan, have prebiotic effects on microbiota in human colon. [ABSTRACT FROM AUTHOR]

Porphyra, one of the most cultured red algae has gained economic importance across the globe for its nutritional benefits. Porphyra is being cultivated, harvested, dried, processed and consumed in large quantities in south eastern countries. It contains relatively high amounts of proteins, carbohydrates, and micronutrients. Exploitation of its fundamental attributes led to the discovery of various biologically active compounds like polysaccharides, phycobiliproteins and peptides with effective pharmacological applications. In this review, a systematic account of the research accomplished in the past decade and up-to-date overview of various bioactive compounds and its pharmacological implications has been compiled. This review summarizes the bioactivities like antioxidative, immunomodulatory, antihypertensive, anticoagulant and anticancer properties of the bioactive compounds from Porphyra. [ABSTRACT FROM AUTHOR]

Macroalgae polysaccharides are phytochemicals that are beneficial to human health. In this study, response surface methodology was applied to optimize the extraction procedure of Pyropia yezoensis porphyran (PYP). The optimum extraction parameters were: 100 °C (temperature), 120 min (time), and 29.32 mL/g (liquid–solid ratio), and the maximum yield of PYP was 22.15 ± 0.55%. The physicochemical characteristics of PPYP, purified from PYP, were analyzed, along with its lipid-lowering effect, using HepG2 cells and Drosophila melanogaster larvae. PPYP was a β-type sulfated hetero-rhamno-galactan-pyranose with a molecular weight of 151.6 kDa and a rhamnose-to-galactose molar ratio of 1:5.3. The results demonstrated that PPYP significantly reduced the triglyceride content in palmitic acid (PA)-induced HepG2 cells and high-sucrose-fed D. melanogaster larvae by regulating the expression of lipid metabolism-related genes, reducing lipogenesis and increasing fatty acid β-oxidation. To summarize, PPYP can lower lipid levels in HepG2 cells and larval fat body (the functional homolog tissue of the human liver), suggesting that PPYP may be administered as a potential marine lipid-lowering drug.

Porphyran is a promising bioactive polysaccharide majorly composed of 4-linked α- l -galactopyranose-6-sulfate (L6S) and 3-linked β- d -galactopyranose (G) disaccharide repeating units. Carbohydrate-binding modules (CBMs) have been verified to be essential tools for investigating polysaccharides. However, no confirmed CBM binding to porphyran has been hitherto reported. In this study, an unknown domain with a predicted β-sandwich fold from a potential GH86 porphyranase was discovered, and further recombinantly expressed. The CBM protein (named FvCBM99) presented a desired specificity for porphyran tetrasaccharide with an affinity constant of 1.9 × 10−4 M, while it could not bind to agarose tetrasaccharide. The sequence novelty and well-defined function of FvCBM99 and its homologs reveal a new CBM family, CBM99. Besides, the application potential of FvCBM99 in in situ visualization of porphyran was demonstrated. The discovery of FvCBM99 provides a favorable tool for future studies of porphyran. • A novel CBM domain with a desired specificity was discovered. • The CBM binds to porphyran tetrasaccharide, but not to agarose tetrasaccharide. • The sequence novelty and defined function of the CBM reveal a new CBM family. • Based on this CBM, a fluorescent probe for porphyran was constructed. • The CBM could serve in the in situ visualization of porphyran. [ABSTRACT FROM AUTHOR]

The anti-inflammatory properties of porphyrans (D1–D4) obtained from four discolored nori ( Pyropia yezoensis ) with different growth backgrounds were studied to examine possible variations in their bioactivities. Elution profiles of the porphyrans on Sepharose 4B indicated that D2-porphyran had relatively lower-molecular-size porphyrans than the other porphyrans. Inhibitory activities of the four porphyrans against nitric oxide (NO) and tumor necrosis factor-α (TNF-α) secretion by lipopolysaccharide (LPS)-stimulated RAW264.7 cells were different, whereas no significant differences were observed in the sulfate and anhydrogalactose levels. D2-porphyran showed the highest inhibitory activity against NO and TNF-α secretion by LPS-stimulated RAW264.7 cells, whereas D3- and D4-porphyrans had almost no activity. All porphyrans were efficiently degraded by free radical generated with ascorbate and hydrogen peroxide. The free-radical degradation resulted in a significant increase in the inhibitory activities of the four porphyrans against NO and TNF-α secretion, with varying rates depending on the porphyrans. The ability of D2-porphyran to suppress the receptor activator of nuclear factor κB ligand (RANKL)-induced osteoclastogenesis in RAW264.7 cells was also significantly enhanced after degradation. Our results suggest that molecular size is an important factor affecting the anti-inflammatory activity of porphyrans, and radical degradation might be a promising procedure to obtain active low-molecular-size porphyrans. [ABSTRACT FROM AUTHOR]

Safe and efficient therapeutic agents for bone diseases are required in natural sources. We previously found that edible seaweed-derived polysaccharide porphyran exhibited anti-inflammatory effects through the down regulation of nuclear factor-κB. The aim of this study was to investigate the availability of porphyran as a therapeutic agent for bone diseases. The effects of porphyran on receptor activator of nuclear factor κB ligand (RANKL)-induced osteoclastogenesis in RAW264.7 cells were examined. Porphyran suppressed RANKL-induced osteoclast formation in a concentration-dependent manner (6.25-50 μg/ml) without any cytotoxic effects. Furthermore, real-time polymerase chain reaction analyses indicated that porphyran at 50 μg/ml significantly attenuated the RANKL-induced increase in the mRNA levels of osteoclastogenesis-related marker genes such as nuclear factor of activated T cells, tartrate-resistant acid phosphatase, cathepsin K, and matrix metalloproteinase-9 in RAW264.7 cells. To our knowledge, this is the first report showing that edible-seaweed-derived polysaccharide porphyran can suppress RANKL-induced osteoclastogenesis. Our results suggest that porphyran can be used as a safe therapeutic agent to improve osteoclast-related pathological conditions. [ABSTRACT FROM AUTHOR]

The application of carbon paste electrodes modified with porphyran-capped gold nanoparticles (CPE/AuNps-PFR) to detect an important anticancer drug, 5-fluorouracil (5-FU), is described. Gold nanoparticles (AuNps) were synthesized through a green one-pot route, by using porphyran (PFR) (a sulfated polysaccharide extracted from red seaweed) as reducing and stabilizing agent. The reaction temperature and the concentrations of AuCl 4 − and PFR for AuNps-PFR synthesis were optimized by using a 2 3 full factorial design with central point assayed in triplicate. The smallest particle size (128.7 nm, obtained by DLS) was achieved by employing a temperature of 70 °C and AuCl 4 − and PFR concentrations equal to 2.5 mmol L −1 and 0.25 mg mL −1 , respectively. The AuNps-PFR nanocomposite was characterized by UV–vis spectroscopy, FTIR, DLS, TEM, XRD and zeta potential, which proved that PFR was effective at reducing and capping the AuNps. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) experiments showed that the nanocomposite could enhance the electrochemical performance of the electrodes, as a consequence of the high conductivity and large surface area presented by the AuNps. The CPE/AuNps-PFR was able to electrocatalyze the oxidation of 5-FU by CV and differential pulse voltammetry (DPV). A linear relationship between the DPV peak currents and 5-FU concentration was verified in the range from 29.9 to 234 μmol L −1 in 0.04 mol L −1 BR buffer solution pH 8.0. Detection and quantification limits were found to be 0.66 and 2.22 μmol L −1 , respectively. Besides the good sensitivity, CPE/AuNps-PFR showed reproducibility and did not suffer significant interference from potentially electroative biological compounds. The good analytical performance of the modified electrode was confirmed for determining 5-FU in pharmaceutical formulations, with good percent recoveries (ranging from 96.6 to 101.4%) and an acceptable relative standard deviation (RSD = 2.80%). [ABSTRACT FROM AUTHOR]

Objectives: Aim of the present work was to investigate the anti-inflammatory, analgesic and antiulcer effects of red seaweed Porphyra vietnamensis (P. vietnamenis). Materials and Methods: Aqueous (POR) and alcoholic (PE) fractions were successfully isolated from P. vietnamenis. Further biological investigations were performed using a classic test of paw edema induced by carrageenan, writhing induced by acetic acid, hot plate method and naproxen induced gastro-duodenal ulcer. Results: Among the fractions POR showed better activity. POR and PE significantly (p < 0.05) reduced carrageenan induced paw edema in a dose dependent manner. In the writhing test POR significantly (p < 0.05) reduced abdominal writhes than PE. In hot plate method POR showed better analgesic activity than PE. POR showed comparable ulcers reducing potential (p

The hypolipidemic and antioxidant effects of porphyran from the red algae Porphyra haitanensis as a dietary supplement were evaluated in mice. The levels of serum TC, TG and LDL-C in MP group increased significantly (p < 0.05 or p < 0.01) by 28.5%, 29.4% and 33.5% compared with the model group. These significant rises were accompanied by significant declines of plasma HDL-C by 21.6% compared with the model group. In addition, the liver content of malondialdehyde significantly decreased, while the superoxide dismutase, catalase, glutathione peroxidase activities significantly increased. The levels of serum SOD and GSH-Px in MP group increased significantly by 51.2% and 99.6% compared with the model group. The results suggested that porphyran could be used as functional foods and natural drugs in preventing the hyperlipidemia and this activity might be attributed to its antioxidant potential. [ABSTRACT FROM AUTHOR]

Seaweed has been increasingly researched in recent years and many of the active substances extracted from algae have been shown to have a wide range of biological activities and have found applications in agriculture, medicine and other fields. Red algae Porphyra is a rich and widely distributed species with high nutritional value. Porphyran extracted from Porphyra has been found to have good antioxidant, immune modulating, anti-aging and hypoglycaemic effects. The biological activity of oligo-porphyran, obtained by degradation of porphyran, is superior to that of its source porphyran. It is therefore important to find methods that can effectively degrade porphyran, and the main focus now is on finding suitable porphyranases to degrade porphyran to prepare oligo-porphyran. This paper described and summarized the biological activity and preparation of porphyran and oligo-porphyran, and highlights the progress of porphyranase research. • The different preparation methods of porphyran and porphyran oligosaccharide have been summarized and discussed. • The various biological activities of porphyran and porphyran oligosaccharide have been described and summarized. • The progress of porphyranase research has been systematically described. • The potential applications of porphyran and porphyran oligosaccharide have been discussed. [ABSTRACT FROM AUTHOR]

Porphyran, a polysaccharide composed of red algae, is a source of a multifunctional oligosaccharide material and raw biomass with various physiological activities. The glycolysis of porphyrans into oligosaccharides through various porphyranases is an approach for obtaining high-quality and promising alternative resources. In this study, porphyran was extracted from Porphyra yezoensis and used as a research substrate. We also established an efficient hydrolysis method using an enzymatic complex obtained through cohesin-dockerin interactions that degrade natural polysaccharides. The cohesion-dockerin interaction is designed to genetically bind the dockerin module to the end of an existing enzyme and then attach the cohesin module to obtain a protein complex. The designed protein complex has been shown to further increase the activity on the substrate, which can be considered a useful method to obtain efficient oligosaccharides or monosaccharides through hydrolysis of red algae for bioresources. ● We constructed porphyranolytic enzyme complexes for synergistic porphyrin degradation. ● Enzymatic hydrolysis of porphyran showed 3.73 times higher by enzyme complexes. ● The natural substrates were decomposed to yield a 1.2-fold increase in reducing sugars. ● This biological strategy is a new potential conversion tool for red algae utilization. [ABSTRACT FROM AUTHOR]

Porphyran is known to inhibit immune cell function. Previously, porphyran was shown to prevent lipopolysaccharide-induced sepsis in mice. However, studies on the inhibitory effects of porphyran during colitis are currently lacking. In this study, we evaluated the effects of Pyropia yezoensis- derived porphyran on dextran sodium sulfate (DSS)-induced acute and chronic colitis. The oral or intraperitoneal administration of porphyran inhibited the progression of DSS-induced colitis in mice, with the former also preventing immune cell infiltration in the colon. The levels of intracellular interferon-γ and interleukin-17 in T cells decreased when porphyran was administered orally. Porphyran inhibited T cell activation by suppressing dendritic cells (DCs) and macrophages. Porphyran prevented pathogen-associated molecular pattern and damage-associated molecular pattern-dependent DC and macrophage activation. Finally, porphyran attenuated chronic colitis caused via the long-term administration of DSS. These findings indicate that the oral administration of porphyran can inhibit DSS-induced colitis by suppressing DC and macrophage activation. • Porphyran administered orally alleviated DSS-induced murine colitis. • Porphyran prevented immune cell infiltration during DSS-induced colitis. • Porphyran inhibited DAMP and PAMP-dependent activation of DCs. • DSS-induced chronic inflammation in the colon was inhibited by porphyrin. [ABSTRACT FROM AUTHOR]

Seaweeds are high in bioactive chemicals frequently used to treat human illnesses. Porphyran is a polysaccharide found in the red seaweeds of the genus Porphyra. Porphyran has been discovered to have immunomodulatory, anti-inflammatory activity, and anti-cancer effects via boosting immunity and targeting important apoptotic molecules, making them potential chemotherapeutic or chemopreventive drugs. Polysaccharide-mediated dynamic control of apoptosis and autophagy in cancer has been a viable treatment with low cytotoxicity with high efficacy. Thus, comprehending the influence of porphyran on human health and their molecular mechanisms would open up a new paradigm in cancer therapies. Also, the importance of apoptotic/autophagy modulating porphyran in cancer therapy has been highlighted as the future direction of improved nano-formulation for improved clinical efficacy. This review focuses on the current research into porphyran's anti-cancer efficacy and putative mechanisms of action through apoptosis and autophagy in various cancers, as well as its potential chemotherapeutic treatment in near future. [Display omitted] [ABSTRACT FROM AUTHOR]

The pharmacological values of marine algal polysaccharides on gut health are being recognized in recent research. However, the protective effect of degraded polysaccharides from Porphyra haitanensis (PHP-D) on the colonic mucosal barrier damaged in ulcerative colitis is poorly understood. The purpose of this study was to investigate how PHP-D could maintain the integrity of colonic mucosal layer mediated by microbiota in a dextran sulfate sodium (DSS)-induced colitis mouse model. Structural analysis revealed that PHP-D had a typical porphyran structure having a backbone of alternating (1 → 3)-linked β-d-galactopyranose units linked to either (1 → 4)-3,6-anhydro-α-l-galactopyranose units or (1 → 4)-linked α-l-galactose-6-sulfate units. An in vivo study demonstrated that PHP-D treatment reduced the severity of DSS-induced ulcerative colitis. 16S rRNA phylogenetic sequencing revealed that PHP-D affected the diversity of gut microbiota with an increase of Bacteroides , Muribaculum , and Lactobacillus species. Similarly, PHP-D increased levels of short-chain fatty acids. Furthermore, PHP-D restored mucus thickness and improved the expression of tight junction proteins. This work demonstrates that PHP-D is capable of enhancing a colonic mucosal barrier. These outcomes offer unique perspectives on the potential application of P. haitanensis as a promising natural product for the management of ulcerative colitis.

Porphyran, a sulfated polysaccharide, isolated from discolored nori ( Porphyra yezoensis ) (dc-porphyran) and one fraction (F1) purified from dc-porphyran by DEAE-chromatography showed the protective effects on LPS-induced endotoxin shock in mice. Intraperitoneal (i.p.) treatment with dc-porphyran or F1 (100 mg/kg) 60 min prior to i.p. injection of LPS (30 mg/kg) completely protected mice from LPS lethality. At 10 mg/kg concentration, F1 demonstrated more protection than dc-porphyran. Intravenous (i.v.) challenge of LPS, even at 20 mg/kg, was more lethal than i.p. administration; i.v. injection of F1 (100 mg/kg) with LPS significantly improved the survival rate. However, i.v. dc-porphyran (100 mg/kg) produced an even lower survival rate than that of LPS alone. We examined pro-inflammatory mediators such as NO and TNF-α in serum. F1 significantly reduced the levels of these markers. Additionally, F1 significantly decreased the malondialdehyde level in the liver, a marker of oxidative stress, while dc-porphyran had almost no effect. Furthermore, F1 significantly decreased the production of TNF-α and NO in peritoneal exudate cells harvested from LPS-challenged mice, while dc-porphyran treatment showed a lesser decrease. Our results suggest that porphyran isolated from discolored nori, especially F1, is capable of suppressing LPS-induced endotoxin shock in vivo . [ABSTRACT FROM AUTHOR]

Porphyran is a sulfated polysaccharide extracted from Pyropia, a genus of marine red algae. In this study, the biological activity of porphyran from Pyropia yezoensis as an oral hypolipidemic agent in Institute of Cancer Research (ICR) mice was investigated. Porphyran lowered serum triglyceride (TG), total cholesterol (TC), and low-density lipoprotein cholesterol/high-density lipoprotein cholesterol (LDL-C/HDL-C) ratio 28 days after administration. Porphyran at a dose of 200 mg kg d can decrease the percentage of body weight gain (BWG) and serum lipid profiles of mice significantly, similar to Zhibituo (a hypolipidemic drug approved by the China Food and Drug Administration in 2009). The mice that have taken porphyran showed an obvious increase in the fecal TC and TG compared with the blank control group. The liver weight, lipid composition (TG and TC), liver damage index (serum alanine aminotransferase, ALT; aspartate aminotransaminase, AST; and alkaline phosphatase, ALP), and hepatocyte morphology results in mice on a high-fat diet imply that dietary administration of porphyran can alleviate liver damage induced by the diet. Therefore, porphyran may be useful as a functional food additive, hypolipidemic, and liver-protective agent. [ABSTRACT FROM AUTHOR]

Objectives: Aim of the present work was to investigate the antiinflammatory, analgesic and antiulcer effects of red seaweed Porphyra vietnamensis (P. vietnamenis). Materials and Methods: Aqueous (POR) and alcoholic (PE) fractions were successfully isolated from P. vietnamenis. Further biological investigations were performed using a classic test of paw edema induced by carrageenan, writhing induced by acetic acid, hot plate method and naproxen induced gastro-duodenal ulcer. Results: Among the fractions POR showed better activity. POR and PE significantly (p < 0.05) reduced carrageenan induced paw edema in a dose dependent manner. In the writhing test POR significantly (p < 0.05) reduced abdominal writhes than PE. In hot plate method POR showed better analgesic activity than PE. POR showed comparable ulcers reducing potential (p<0.01) to that of omeprazole, and has more ulcer reducing potential then PE. Conclusions: The results of this study demonstrated that P. vietnamenis aqueous fraction possesses biological activity that is close to the standards taken for the treatment of peripheral painful or/and inflammatory and ulcer conditions. [ABSTRACT FROM AUTHOR]