Bangia Fuscopurpurea Research Articles

A polysaccharide from edible red seaweed Bangia fusco-purpurea prevents obesity in high-fat diet-induced C57BL/6 mice

The study aimed to investigate the impacts of a polysaccharide (BFP) from Bangia fusco-purpurea on high-fat diet (HFD)-induced obesity in C57BL/6 mice, as well as its underlying mechanisms. Our results showed that orally administrated BFP was more effective than inulin (INU) in reducing body weight and fat accumulation in obese mice, indicating its anti-obesity effect. BFP effectively improved the compositions and metabolites of intestinal microbiota in obese mice, leading to enhanced energy metabolism and lipid metabolism, thus contributing to its anti-obesity effect. Notably, the better anti-obesity effect of BFP compared to INU were attributed to their varying degrees of modulation of specific intestinal microbial taxa, such as Clostridium and Aerococcus, as well as the regulation of differential metabolites (including biotin, piperine, G6P, etc.) also varies. Also, both in vitro (3T3-L1 preadipocytes) and in vivo (HFD-induced obese mice) models confirmed that BFP achieved anti-obesity effect attributed to enhance energy metabolism, promote lipolysis, increase fatty acid oxidation, and inhibit adipogenesis via activating the AMP-activated protein kinase and Acetyl-CoA carboxylase signaling pathways and suppressing the peroxisome proliferator-activated receptor γ expression. Our findings suggest that BFP has the potential to be used as prebiotics, dietary agents, and nutritional supplements against obesity.

Ultra-high pressure assisted extraction of polysaccharide from Bangia fusco-purpurea: Structure and in vitro hypolipidemic activity

The structure and in vitro hypolipidemic activity of Bangia fusco-purpurea polysaccharide (BFP) assisted extracted with ultra-high pressure (UHP) at 100–600 MPa were studied. Compared to native BFP, UHP assisted extracted BFP had a more loose network structure with higher total sugar and uronic acid contents while less molecular weight (p < 0.05). Moreover, UHP assisted extraction significantly improved the in vitro hypolipidemic and antioxidant activity of BFP. Especially at 400 MPa UHP, the cholesterol adsorption and antioxidant capacities of BFP were increased by approximately 38.02 % and 11.69 %–32.29 %, respectively. BFP with UHP assisted extraction could alleviate oleic acid-induced lipid accumulation and lipid oxidation in HepG2 cells more effectively by activating the AMPK signaling pathway as well as inhibiting PPARγ expression, which was much related with its reduced molecular weight and loose network structure. The findings indicated that UHP assisted extracted BFP has better potential to develop natural hypolipidemic agent.

In vitro neuroprotective effects and in silico evaluation of the pharmacological potential of two phenolic acids and a derivative originated from the edible red macroalga (Bangia fuscopurpurea)

Most previous studies on the bioactive substances from the edible red macroalga (Bangia fuscopurpurea) have concentrated on the polysaccharides and proteins. We explored the possible effects of two phenolic acids (HBP2—3) and two derivatives (HBP1 and HBP4) originated from Bangia fuscopurpurea and two structural analogues in an in vitro model of Parkinson’s disease. We also performed in silico evaluation of the pharmacological potential of these six compounds. Our present study showed that HBP1—3 had neuroprotective effects. Moreover, HBP3 (10 nM) could protect SH-SY5Y cells from 6-hydroxydopamine (6-OHDA) damage via activation of the nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) cascade, and the up-regulation of this pathway could inhibited reactive oxygen species (ROS) production. In addition, we speculated the preliminary structure–activity relationships on the neuroprotective effects of HBP1—3. This study demonstrated that neuroprotective effects of HBP1—3 originated from Bangia fuscopurpurea.

Purification and Screening of the Antialgal Activity of Seaweed Extracts and a New Glycolipid Derivative against Two Ichthyotoxic Red Tide Microalgae Amphidinium carterae and Karenia mikimotoi.

Ichthyotoxic red tide is a problem that the world is facing and needs to solve. The use of antialgal compounds from marine macroalgae to suppress ichthyotoxic red tide is considered a promising biological control method. Antialgal substances were screened and isolated from Bangia fusco-purpurea, Gelidium amansii, Gloiopeltis furcate, Hizikia fusifarme, Laminaria japonica, Palmaria palmata, and Sargassum sp. to obtain new materials for the development of algaecides against ichthyotoxic red tide microalgae using bioactivity-guided isolation methods. The fractions of seven macroalgae exhibited selective inhibitory activities against Amphidinium carterae and Karenia mikimotoi, of which the ethyl acetate fractions had the strongest and broadest antialgal activities for the two tested red tide microalgae. Their inhibitory effects on A. carterae and K. mikimotoi were even stronger than that of potassium dichromate, such as ethyl acetate fractions of B. purpurea, H. fusifarme, and Sargassum sp. Thin-layer chromatography and ultraviolet spectroscopy were further carried out to screen the ethyl acetate fraction of Sargassum sp. Finally, a new glycolipid derivative, 2-O-eicosanoyl-3-O-(6-amino-6-deoxy)-β-D-glucopyranosyl-glycerol, was isolated and identified from Sargassum sp., and it was isolated for the first time from marine macroalgae. The significant antialgal effects of 2-O-eicosanoyl-3-O-(6-amino-6-deoxy)-β-D-glucopyranosyl-glycerol on A. carterae and K. mikimotoi were determined.

Screening and mechanistic study of antioxidant peptides from Bangia fusco-purpurea targeting the Keap1–Nrf2 pathway

Using 2236 peptides derived from Bangia fusco-purpurea as ligands and the Kelch domain of Kelch-like ECH-associated protein 1 as the receptor, molecular docking was employed to screen peptides with strong inhibitory effects on Kelch-like ECH-associated protein 1–nuclear erythroid 2-related factor interactions. Subsequently, an H2O2-induced oxidative damage model was established using human umbilical vein endothelial cells to validate the results. The most active antioxidant peptides, IAY and TIL, induced nuclear erythroid 2-related factor translocation from the cytoplasm to the nuclei of human umbilical vein endothelial cells when subjected to oxidative damage. Nuclear erythroid 2-related factor activation resulted in the upregulation of the downstream target proteins, including nicotinamide adenine dinucleotide phosphate, quinone oxidoreductase 1, heme oxygenase-1, glutathione, and superoxide dismutase. This cascade reduced the malondialdehyde and reactive oxygen species levels, thereby alleviating oxidative stress, and inhibited H2O2-induced cell apoptosis by regulating apoptosis-related proteins. This study successfully identified IAY and TIL as antioxidant peptides that capable of interfering with Kelch-like ECH-associated protein 1–nuclear erythroid 2-related factor interactions, and elucidated the underlying cellular and molecular mechanisms, laying the groundwork for further research and application of antioxidant peptides.

Extraction, Isolation and Biological Activity of Two Glycolipids from Bangia fusco-purpurea.

In order to explore the extraction and activity of macroalge glycolipids, six macroalgae (Bangia fusco-purpurea, Gelidium amansii, Gloiopeltis furcata, Gracilariopsis lemaneiformis, Gracilaria sp. and Pyropia yezoensis) glycolipids were extracted with five different solvents firstly. Considering the yield and glycolipids concentration of extracts, Bangia fusco-purpurea, Gracilaria sp. and Pyropia yezoensis were selected from six species of marine macroalgae as the raw materials for the extraction of glycolipids. The effects of the volume score of methanol, solid-liquid ratio, extraction temperature, extraction time and ultrasonic power on the yield and glycolipids concentration of extracts of the above three macroalgae were analyzed through a series of single-factor experiments. By analyzing the antioxidant activity in vitro, moisture absorption and moisturizing activity, the extraction process of Bangia fusco-purpurea glycolipids was further optimized by response surface method to obtain suitable conditions for glycolipid extraction (solid-liquid ratio of 1:27 g/mL, extraction temperature of 48 °C, extraction time of 98 min and ultrasonic power of 450 W). Bangia fusco-purpurea extracts exhibited a certain scavenging effect on DPPH free radicals, as well as good moisture-absorption and moisture retaining activities. Two glycolipids were isolated from Bangia fusco-purpurea by liquid-liquid extraction, silica gel column chromatography and thin-layer chromatography, and they showed good scavenging activities against DPPH free radicals and total antioxidant capacity. Their scavenging activities against DPPH free radicals were about 60% at 1600 µg/mL, and total antioxidant capacity was better than that of Trolox. Among them, the moisturizing activity of a glycolipid was close to that of sorbierite and sodium alginate. These two glycolipids exhibited big application potential as food humectants and antioxidants.

Inhibitory effect of a polysaccharide prepared from edible red seaweed Bangia fusco-purpurea on Escherichia coli by regulating its metabolisms

In this study, the antimicrobial activity on Escherichia coli (E. coli) of a polysaccharide (BFP) prepared from Bangia fusco-purpurea with the underlying mechanism was investigated. The results showed that BFP could against the growth of E. coli in a concentration-dependent manner. The inhibitory effect of BFP on E. coli might be through disrupting the morphology, increasing the intracellular reactive oxygen species levels, and decreasing the Ca2+-Mg2+-ATPase activity in E. coli. Furthermore, BFP significantly reduced the biofilm formation in E. coli by down-regulating the critical biofilm-related genes, including flhD, flhC, fliM, csgA, and csgD, especially fliM, and weakened the bacteria's infection and pathogenic potentials. Notably, the metabolomic analysis demonstrated that BFP performed antimicrobial activity mainly by up-regulating the sphingosine and phospholipids metabolites, down-regulating the amino acid metabolites, and the two-component system in E. coli. The findings advance the understanding on the underlying mechanisms of red seaweed polysaccharide BFP against E. coli, and further provide the scientific basis for developing BFP as a natural antimicrobial agent applied in food additives or pharmaceutical ingredients.

Integrative analyses of transcriptomes and metabolomes provide insight into salinity adaption in Bangia (Rhodaphyta)

The salinity of the external environment poses a serious threat to most land plants. Although seaweeds can adapt to this, intertidal species are subject to wide fluctuations in salinity, including hypo- and hyper-saline conditions. The red algal genus Bangiales is a typical example; it is one of the oldest eukaryotes with sexual reproduction and has successfully adapted to both marine and freshwater environments. However, there is a dearth of research focused on elucidating the mechanism by which marine Bangia (Bangia fuscopurpurea) adapts to hypo-salinity, as well as the mechanism by which freshwater Bangia (Bangia atropurpurea) adapts to hyper-salinity. The objective of this study is to employ third-generation full-length transcriptome data and untargeted metabolome data, to provide insights into the salinity adaptation mechanism of as well as the evolutionary relationship between both Bangia species. B. fuscopurpurea and B. atropurpurea exhibited 9112 and 8772 differentially expressed genes (DEGs), respectively, during various periods of hyper-saline condition. These genes were primarily enriched in secondary metabolites and energy-related metabolic pathways. Additionally, B. fuscopurpurea displayed 16,285 DEGs during different periods of hypo-saline condition, which were mainly enriched in metabolic pathways related to ion transport and membrane proteins. In the hyper- and hypo-saline adapt response processes of B. fuscopurpurea, a total of 303 transcription factors were identified, which belonged to 26 families. Among these, 85 and 142 differential transcription factors were identified, respectively, mainly belonging to the C2H2 and MYB family. Similarly, in the response process of B. atropurpurea to hyper-saline condition, a total of 317 transcription factors were identified, mainly belonging to 17 families. Among these, 121 differential transcription factors were identified, mainly belonging to the C2H2 and bZIP family. Furthermore, a correlation analysis was conducted to examine the relationship between the transcriptional and metabolic levels of both species under saline adaptation. The findings demonstrated that Bangia exhibits intricate adaptations to salinity, which involve swift regulation of its photosynthetic processes, alternations in membrane contents, and a robust anti-oxidation system to mitigate the effects of excess redox energy during exposure to varying salinity. Notably, the unsaturated fat and glutathione metabolic pathways were found to be significantly enriched in this context.

Effect of phytol isolated from edible red alga (Bangia fusco-purpurea) on tyrosinase inhibition and its application on food preservation

Enzymatic browning is one of the major problems in food industry, especially for damaged fruits and vegetables during post-harvest handling and processing. An efficient approach to reduce enzymatic browning is to inhibit key polyphenol oxidases causing browning reactions, for example tyrosinase. Tyrosinase inhibitors from natural sources are more attractive considering the importance of food safety and application. B. fusco-purpurea is a edible alga with potential inhibiting tyrosinase. Therefore, we purified and characterized new tyrosinase inhibitors from the seaweed. Phytol, identified in the crude extract of B. fusco-purpurea inhibited tyrosinase with half maximal inhibitory concentration (IC50) of 32.4 ± 3.06 μg/mL as a reversible and competitive inhibitor. Phytol acted as tyrosinase inhibitor, antioxidant, and reducing agent in inhibition of enzymatic browning mechanisms. Then, with the increase concentration of phytol added in homogenates squeezed from apple, pear, and potato, higher browning inhibition was observed with browning index increased. Our findings suggest that phytol isolated from edible red alga could be a potential anti-browning agent.

Effect of red algae powder on gel properties and in vitro hypolipidemic activity of fish balls

In this study, gel properties and in vitro hypolipidemic activity of fish balls with red algae powder including Porphyra and Bangia fusco-purpurea powder were investigated after frozen storage for 7 d. Water holding capacity and gel structure are important factors affecting the quality of minced fish products. The results showed that Porphyra powder at 0.5 % significantly increased water holding capacity of fish balls while Bangia fusco-purpurea powder not (p ≥ 0.05), and both Porphyra and Bangia fusco-purpurea powder enhanced protein interactions, the cross-linking of actin and gel network structure, but 1.0 % of them decreased water holding capacity, resulting the loose and irregular gel structure of fish balls with excessive aggregation partially (p < 0.05). Moreover, both Porphyra and Bangia fusco-purpurea powder higher than 0.5 % could significantly improve the bile salt binding ability of fish balls (p < 0.05), especially Bangia fusco-purpurea powder at 1.0 % also significantly increased the inhibition rate of pancreatic lipase of fish balls (p < 0.05), suggesting the enhanced hypolipidemic activity for fish balls with red algae powder. These findings indicated that surimi products with desirable gel and hypolipidemic activity can be designed by adding appropriate type and concentration of red algae powder.

High-pressure homogenization treatment of red seaweed Bangia fusco-purpurea affects the physicochemical, functional properties and enhances in vitro anti-glycation activity of its dietary fibers

In this study, high-pressure homogenization (HPH) technique was applied for the pretreatment of Bangia fusco-purpurea, and the effect of HPH on the composition, physiochemical and functional properties, and in vitro anti-glycation activity of dietary fiber from this seaweed (B. fusco-purpurea dietary fiber, BDF) was studied. Results showed that HPH significantly increased water-soluble dietary fiber (SDF) content in BDF. Water-holding capacity, oil-holding capacity, and glucose delay dialysis index of BDF were significantly enhanced after HPH treatment. Additionally, HPH significantly improved the in vitro anti-glycation activity of BDF by inhibiting the formation of advanced glycation end products (AGEs) and mitigating damage induced by AGEs on intestinal cells. These improvements could be attributed to the formation of the coarse and porous structure and greater exposure of hydroxyl groups of BDF caused by HPH treatment. These results implied the potential of HPH in seaweed processing and provided a scientific basis for the in-depth, comprehensive utilization of B. fusco-purpurea. Industrial relevanceHPH is an emerging non-thermal food processing technique with promising application potential in food industry. In this study, we found that HPH technique could significantly change the composition, improve physiochemical and functional properties and enhance anti-glycation activity of dietary fiber from seaweed B. fusco-purpurea. Our results validated the efficiency of HPH on dietary fiber modification, implying the potential of HPH in food industry and healthy industry.

Interaction Network Construction and Functional Analysis of the Plasma Membrane H+-ATPase in Bangia fuscopurpurea (Rhodophyta).

Salinity is a serious threat to most land plants. Although seaweeds adapt to salty environments, intertidal species experience wide fluctuations in external salinities, including hyper- and hypo-saline stress. Bangia fuscopurpurea is an economic intertidal seaweed with a strong tolerance to hypo-salinity. Until now, the salt stress tolerance mechanism has remained elusive. Our previous study showed that the expression of B. fuscopurpurea plasma membrane H+-ATPase (BfPMHA) genes were the most upregulated under hypo-salinity. In this study, we obtained the complete sequence of BfPMHA, traced the relative expression of this BfPMHA gene in B. fuscopurpurea under hypo-salinity, and analyzed the protein structure and properties based on the gene's sequence. The result showed that the expression of BfPMHA in B. fuscopurpurea increased significantly with varying hypo-salinity treatments, and the higher the degree of low salinity stress, the higher the expression level. This BfPMHA had typical PMHA structures with a Cation-N domain, an E1-E2 ATPase domain, a Hydrolase domain, and seven transmembrane domains. In addition, through the membrane system yeast two-hybrid library, three candidate proteins interacting with BfPMHA during hypo-saline stress were screened, fructose-bisphosphate aldolase (BfFBA), glyceraldehyde 3-phosphate dehydrogenase (NADP+) (phosphorylating) (BfGAPDH), and manganese superoxide dismutase (BfMnSOD). The three candidates and BfPMHA genes were successfully transferred and overexpressed in a BY4741 yeast strain. All of them significantly enhanced the yeast tolerance to NaCl stress, verifying the function of BfPMHA in salt stress response. This is the first study to report the structure and topological features of PMHA in B. fuscopurpurea and its candidate interaction proteins in response to salt stress.

Ascorbate−glutathione cycle involving in response of Bangia fuscopurpurea (Bangiales, Rhodophyta) to hyposalinity

Bangia fuscopurpurea is a widespread intertidal seaweed that is commercially cultured in China. This seaweed is frequently exposed to hyposalinity stress, but little is known about the adaptation mechanisms. Ascorbate−glutathione (AsA−GSH) cycle plays important roles in many organisms under a variety of abiotic stress, including hyposaline stress. In this study, we investigated the response of key metabolites and enzymes involved in the AsA−GSH cycle of B. fuscopurpurea under hyposalinity, with the addition of exogenous GSH and Lbuthionine-sulfoximine (BSO). The quantification of BfAPX gene expression was assessed across varied treatment regimens. And the putative interaction proteins of BfAPX were screened by yeast two hybrid system. It was found that under hyposalinity (15 and/or 0 psu), the content of reduced glutathione (GSH), total glutathione (GSH+ oxidized glutathione, GSSG) and cysteine, the ratio of GSH/GSSG and ascorbic acid (AsA)/ dehydroascorbic acid (DHA), and the activity of ascorbic acid peroxidase (APX) and monodehydroascorbate reductase (MDHAR) was significantly up-regulated. The hyposality-promoted GSH/GSSG was weakened while the glutathione reductase (GR) activity was promoted by adding exogenous GSH and BSO. The hyposality-promoted AsA/DHA ratio was strengthened by exogenous GSH but weakened by BSO. The dehydroascorbate reductase (DHAR) activity had no significant changes either with or without exogenous GSH under all salinities, while DHAR activity together with DHA content was enhanced by BSO. The expression of APX gene markedly increased under hyposalinity+BSO treatment. Putative interacting proteins of APX, including glutamate dehydrogenase 1a and fructose diphosphate aldolase, were identified through screening. The results indicated that the AsA−GSH cycle was involved in response of B. fuscopurpurea to hyposalinity by means of increasing GSH/GSSG ratio (through promoting GSH biosynthesis pathway and GSH regeneration from GSSG by GR catalyzation) and AsA/DHA ratio (promoting AsA regeneration through MDHAR). These findings would contribute to improve the aquaculture of this promising economic species and unveil how intertidal seaweeds address the global climate challenges.

Pseudobangia corderoi sp. nov. (Bangiales, Rhodophyta) from the Philippines

ABSTRACT A new filamentous bangialean alga, Pseudobangia corderoi sp. nov., is described from the northern Philippines. Locally known as a sea vegetable, this species was previously identified as ‘Bangia fuscopurpurea’. Inferred combined analyses of the nucleus-encoded SSU rDNA and the plastid-encoded RubisCO LSU (rbcL) gene indicate that P. corderoi is sister to another unidentified species of Pseudobangia (originally referred to also as ‘Bangia fuscopurpurea’) from Taiwan. Together, these two taxa formed the closest diverging lineage from Pseudobangia kaycoleae (generitype). Current molecular phylogenies have also yielded monophyly of Pseudobangia and strong support for a sister relationship with the ‘Bangia 2’ lineage. Molecular and geographic analyses clearly differentiate P. corderoi from other filamentous Bangiales, whereas morpho-anatomical analysis identified only one distinguishing character, i.e. larger dimensions of the thalli.

Lactobacillus-fermentation enhances nutritional value and improves the inhibition on pancreatic lipase and oral pathogens of edible red seaweed Bangia fusco-purpurea

Red seaweed contains abundant bioactive ingredients with health benefits. Fermentation is widely used in improving the bioactive ingredients of seaweed materials. However, the types of the active metabolite and changes in biological activity components by the fermentation process remain unknown. In this study, red seaweed Bangia fusco-purpurea was inoculated with Lactobacillus delbrueckii and Lactobacillus plantarum to study bioactive components in supernatants. Results showed that Lactobacillus-fermentation dramatically increased free essential amino acid, trace mineral elements, flavonoids, and polyphenols contents, while decreasing protein and sugar in supernatants. Meanwhile, inhibitions of pancreatic lipase enzyme activities and antibacterial activities against oral pathogenic bacteria were significantly increased by Lactobacillus-fermentation, up to 93.48% and 98.2%, respectively. It might be caused by the increase of polyphenols and flavonoids contents in fermentation supernatants. Also, the biological functions of L. delbrueckii-fermentation were better than that of L. plantarum. Overall, B. fusco-purpurea with Lactobacillus-fermentation has the potential to be special dietary food for improving hyperlipidemia and obesity.

Comparative evaluation of physical characteristics and volatile flavor components of Bangia fusco-purpurea subjected to hot air drying and vacuum freeze-drying

Bangia fusco-purpurea is an economically important seaweed with Fujian characteristics. Given that its harvest is seasonal, drying is often used to remove moisture, extend storage time, and facilitate further processing. Hence, the current study sought to explore the impact of different drying processes on the quality and volatile fingerprints of Bangia fusco-purpurea. To this end, the effects of hot air drying (HAD) and vacuum freeze drying (VFD) on the drying characteristics, microstructure, rehydration, and volatile components of dried B. fusco-purpurea were investigated. The results showed that the water removal efficiency of HAD was significantly higher than that of VFD. However, VFD better preserved the skeletal structure of B. fusco-purpurea than HAD, with a faster rehydration rate and a more uniform cell structure after rehydration. Using electronic nose and comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (GC × GC-TOF MS), significant differences in the volatile profiles of fresh, HAD, and VFD B. fusco-purpurea were assessed. E-nose analysis revealed that both HAD and VFD treatments significantly reduced sulfides, aromatic compounds, and nitrogen oxides in fresh B. fusco-purpurea. However, the alcohol, aldehyde, and ketone contents were lower in the VFD samples compared with HAD and fresh samples, whereas the content of methyl flavor substances was significantly higher. GC × GC-TOF MS analysis revealed that the most abundant volatile categories in HAD and VFD were hydrocarbons, alcohols, and esters. The number of volatile components in the HAD samples was significantly lower than in the VFD and fresh samples. As drying progressed, hydrocarbons and alcohols were formed in dried B. fusco-purpurea due to the thermal degradation of carbohydrates, lipids, amino acids, and the Maillard reaction. There were also significant flavor differences between HAD and VFD B. fusco-purpurea. Thus, although HAD exhibits better drying efficiency, VFD has more significant advantages in terms of product quality.

In vitro fermentation of Bangia fusco-purpurea polysaccharide by human gut microbiota and the protective effects of the resultant products on Caco-2 cells from lipopolysaccharide-induced injury

Polysaccharide extracted from red seaweed Bangia fusco-purpurea (BFP) is a novel sulfated galactan, differed from agarans and carrageenans in fine structure. In this study, in vitro fermentation characteristics of BFP by human gut microbiota and its protective effect on lipopolysaccharide (LPS)-induced injury in Caco-2 cells were investigated. Our results showed that BFP was mainly degraded at transverse colon for 18 h fermentation by gut microbiota with reduced molecular weight. Meanwhile, BFP fermentation was associated with increased short-chain fatty acids (SCFAs) as compared to control group, especially acetic acid was increased to 129.53 ± 0.24 from 82.14 ± 0.23 mmol/L, and butyric acid was up to 1.56 ± 0.004 from 0.62 ± 0.01 mmol/L. Furthermore, BFP promoted abundances of Bacteroidetes and Firmicutes, while decreased numbers of Proteobacteria. The up-regrated beneficial differential metabolites were SCFAs, L-proline, arginine, folic acid, pyridoxamine, thiamine, etc. (p < 0.05), and their related metabolic pathways mainly included mTOR, arginine biosynthesis, and vitamin metabolism. Notably, BFP fermentation products at transverse colon significantly restored cell viability of LPS-treated Caco-2 cells from 73.79 ± 0.48 % to 93.79–99.64 %, which might be caused by increased beneficial differential metabolites (e.g., SCFAs). Our findings suggest that BFP has prebiotic potential and can enhance gut health.

Extraction, Isolation and Characterization of Mycosporine-like Amino Acids from Four Species of Red Macroalgae.

Marine macroalgae is known to be a good source of mycosporine-like amino acids (MAAs), especially red macroalgae. As a new type of active substance with commercial development prospects, the current progress in the extraction, isolation and characterization of MAAs is far from sufficient in terms of effectiveness in application. To determine the extraction processes of MAAs from four species of red macroalgae (Bangia fusco-purpurea, Gelidium amansii, Gracilaria confervoides, and Gracilaria sp.), a series of single-factor and orthogonal experiments were carried out in which the effects of solvents, the solid–liquid ratio, the time of extraction, the extraction degree and the temperature, on the yields of MAA extracts, were analyzed. Further, the isolation and identification of MAAs from Bangia fusco-purpurea and Gracilaria sp. were investigated. The results showed that the solid–liquid ratio, the time of extraction, the extraction degree and the temperature were 1:20 g/mL, 2 h, three times and 40 °C, respectively, when 25% methanol or 25% ethanol were used as the extraction solvent; these values were found to be suitable for the extraction of MAAs from four species of red macroalgae. Silica gel thin-layer chromatography was successfully used, for the first time, for the detection MAAs in this work, and it could be clearly seen that Bangia fusco-purpurea had the highest contents of MAAs among the four species of red macroalgae. MAA extracts from Bangia fusco-purpurea (or Gracilaria sp.) were isolated by silica gel column chromatography to obtain one fraction (or two fractions). The compositions and proportions of the MAAs in these fractions were determined via HPLC-ESI-MS spectra and by comparison with existing studies. Shinorine, palythine and porphyra-334 were found in 95.4% of the T1 fraction, and palythenic acid was found in 4.6% of this fraction, while shinorine, palythine and porphyra-334 were found in 96.3% of the J1 fraction, palythenic acid was found in 3.7% of the J2 fraction, and palythine was found in 100% of the J2 fraction, taken from the MAA extracts found in Bangia fusco-purpurea and Gracilaria sp., respectively. In addition, the relevant compositions and proportions of the MAA extracts taken from Gelidium amansii and Gracilaria confervoides were identified. This was the first study to report on the extraction process, isolation and identification of MAAs from Bangia fusco-purpurea, Gelidium amansii, Gracilaria confervoides, and Gracilaria sp.

Polysaccharides isolated from Bangia fuscopurpurea induce apoptosis and autophagy in human ovarian cancer A2780 cells.

Although ovarian cancer is common, its prognosis remains poor because of drug resistance and early metastasis. Polysaccharides extracted from Bangia fuscopurpurea (BFP) are potential anti‐cancer agents, but the mechanisms underlying their effects in human ovarian cancer remain unclear. Here, we investigated the mechanisms of action of BFP polysaccharides in A2780 ovarian cancer cells using cell migration, invasion, apoptosis, and autophagy assays. Transwell assays indicated that BFP inhibited cell migration and invasion. Flow cytometry analysis showed that BFP treatment induced apoptosis and reactive oxygen species production, while significantly reducing mitochondrial membrane potential. Reverse transcription–polymerase chain reaction and Western blot analyses revealed changes in the expression of apoptosis‐ and autophagy‐related cellular mRNAs and proteins, respectively, following BFP treatment for 24 h. Transmission electron microscopy revealed that BFP induced autophagy in A2780 cells. These findings demonstrate that BFP may be useful for developing functional foods for cancer therapy.

Removal of the fishy malodor from Bangia fusco-purpurea via fermentation of Saccharomyces cerevisiae, Acetobacter pasteurianus, and Lactobacillus plantarum.

The present study aims to evaluate the deodorization of Bangia fusco-purpurea using microorganism fermentation with commercial starter cultures of Saccharomyces cerevisiae, Acetobacter pasteurianus, and Lactobacillus plantarum. The results showed the fermentation with S. cerevisiae, A. pasteurianus, and L. plantarum resulted in significantly decreases (p<.05) of the fishy malodor in B. fusco-purpurea. Among the three strains, S. cerevisiae was the best for reducing the fishy malodor. The optimal inoculum size and fermentation time were 0.2% and 4hr, respectively. After the fermentation with the S. cerevisiae, the content of 1-octen-3-ol, (E)-2-octen-1-ol, hexanal, non-(2E)-enal, (E,E)-2,4-decadienal, 3,5-octadien-2-one, and 2-pentyl-furan were hard to be detected in the seaweed, whereas increases were observed in the concentrations of 2-butyl-1-octanol, cedrol, diisobutyl phthalate, and 2,4-di-t-butylphenol. The odor active value analysis indicated the removal of fishy odor was related to the reduction, dehydrogenation, and deformylating oxygenation of hexanal, nonanal, non-(2E)-enal, and (E,E)-2,4-decadienal and esterification of 1-octen-3-ol and (E)-2-octen-1-ol. Our findings provide a technical and scientific basis for the removal of fishy odor from B. fusco-purpurea. PRACTICAL APPLICATIONS: Bangia fusco-purpurea is a seaweed that can reduce the risks of cardiovascular and chronic metabolic diseases in human body. However, the seaweed has a strong fishy malodor, which largely declines consumer's acceptance. In this study, the commercial starters of Saccharomyces cerevisiae, Acetobacter pasteurianus, and Lactobacillus plantarum were shown to reduce the fishy malodor in B. fusco-purpurea via fermentation. After the fermentation with the microorganisms especially with the S. cerevisiae, the fishy malodor significantly reduced, and the overall aroma acceptance of B. fusco-purpurea products greatly improved. Therefore, this study provides a technical basis for the removal of fishy odor from B. fusco-purpurea and processing value-added products from it and facilitating its health benefits for human.