Grateloupia Livida Research Articles

Novel Antioxidant Peptides from Grateloupia livida Hydrolysates: Purification and Identification.

Grateloupia livida protein was hydrolyzed with various proteases (alkaline protease, Protamex and neutral protease) to obtain anti-oxidative peptides. Antioxidant activity of the enzymatic hydrolysates was evaluated by the DPPH radical scavenging, ABTS radical scavenging and reducing power assays. The results suggested that hydrolysates obtained by neutral protease 1 h hydrolysis displayed the highest antioxidant activity (DPPH IC50 value of 3.96 mg/mL ± 0.41 mg/mL, ABTS IC50 value of 0.88 ± 0.13 mg/mL and reducing power of 0.531 ± 0.012 at 8 mg/mL), and had low molecular weight distribution (almost 99% below 3 kDa). Three fractions (F1–F3) were then isolated from the hydrolysates by using semi-preparative RP-HPLC, and the fraction F3 showed the highest antioxidant ability. Four antioxidant peptides were identified as LYEEMKESKVINADK, LEADNVGVVLMGDGR, LIDDSFGTDAPVPERL, and GLDELSEEDRLT from the F3 by LC-MS/MS. Online prediction showed that the four peptides possessed good water solubility, non-toxic and non-allergenic characteristics. Moreover, the LYEEMKESKVINADK exhibited the highest antioxidant ability. Molecular docking revealed that these peptides could all well bind with Kelch-like ECH-associated protein 1 (Keap1), among which LYEEMKESKVINADK had the lowest docking energy (−216.878 kcal/mol). These results demonstrated that the antioxidant peptides from Grateloupia livida could potentially be used as natural antioxidant.

Photosynthetic Characteristics of Three Cohabitated Macroalgae in the Daya Bay, and Their Responses to Temperature Rises.

Biochemical compositions and photosynthetic characteristics of three naturally cohabitated macroalgae, Ulva fasciata, Sargassum hemiphyllum and Grateloupia livida, were comparably explored in the field conditions in Daya Bay, northern South China Sea, as well as their responses to temperature rise. Chlorophyll a (Chl a) and carotenoids contents of U. fasciata were 1.00 ± 0.15 and 0.57 ± 0.08 mg g−1 in fresh weight (FW), being about one- and two-fold higher than that of S. hemiphyllum and G. livida; and the carbohydrate content was 20.3 ± 0.07 mg g−1 FW, being about three- and one-fold higher, respectively. Throughout the day, the maximal photochemical quantum yield (FV/FM) of Photosystem II (PS II) of these three macroalgae species decreased from morning to noon, then increased to dusk and kept steady at nighttime. Consistently, the rapid light curve-derived light utilization efficiency (α) and maximum relative electron transfer rate (rETRmax) were lower at noon than that at morning- or night-time. The FV/FM of U. fasciata (varying from 0.78 to 0.32) was 38% higher than that of G. livida throughout the day, and that of S. hemiphyllum was intermediate. The superoxide dismutase (SOD) and catalase (CAT) activities in U. fasciata were lower than that in S. hemiphyllum and G. livida. Moreover, the rises in temperature species-specifically mediated the damage (k) caused by stressful high light and the corresponding repair (r) to photosynthetic apparatus, making the r/k ratio increase with the rising temperature in U. fasciata, unchanged in S. hemiphyllum but decreased in G. livida. Our results indicate that U. fasciata may compete with S. hemiphyllum or G. livida and dominate the macroalgae community under aggravatedly warming future in the Daya Bay.

Synthesis and evaluation of Grateloupia Livida polysaccharides-functionalized selenium nanoparticles

Grateloupia Livida polysaccharides-functionalized selenium nanoparticles (GLP-SeNPs) have been successfully prepared in a simple redox system of sodium selenite and ascorbic acid. The size, morphology, structure, stability and thermal behavior were analyzed by various characterization methods. These results showed that, GLP-SeNPs (particle size of 115.54 nm) prepared in optimal synthesis conditions (temperature of 45 °C, reaction time of 3 h, GLP concentration of 1.0 mg/mL and ascorbic acid concentration of 0.04 M) obtained by orthogonal experiments were uniform spherical and could be stable for 30 days at 4 °C. GLP-SeNPs exhibited significant scavenging ability on DPPH, ABTS, hydroxyl radical and superoxide anion radical when compared to GLP and Na2SeO3. GLP-SeNPs showed selective cytotoxicity toward various human cancer cells, but not normal cells. Besides, GLP-SeNPs exhibited low oral acute toxicity. Taken together, GLP-SeNPs might be used as potential diet nutritional supplement or anticancer agent.

Activation of NLRP3 inflammasome in RAW 264.7 cells by polysaccharides extracted from Grateloupia livida (Harv.) Yamada

Polysaccharides have been proven to be involved in the immune response in both anti-inflammation and pro-inflammation due to their distinct pharmacological properties. Recent studies showed that polysaccharides from Grateloupia livida (Harv.) Yamada possessed several biological activities, including anti-oxidant, anti-angiogenic, anti-cancer and antiviral. Our previous work has elucidated the structural features of the polysaccharides (named WGW) by combining ESI-MS with NMR and infrared (IR) spectroscopic analyses. The polysaccharides were mainly composed of galactose linked with sulfate ester, concluding to be μ-carrageenan and κ-carrageenan. The purpose of this study was to investigate the immunoregulation effects of WGW on macrophage RAW 264.7 cell. The cells were treated with WGW for different times, then Griess reagent was applied to detect the production of NO. The results presented that WGW induced the release of NO in large quantities (ranging from 2 µg/mL to 256 µg/mL) and improved the phagocytosis of macrophage RAW264.7 cells. Furthermore, WGW have a predominant role in the improvement of proinflammatory mediators, such TNF-α, IL-1β, iNOS, MMP-9 and COX2. Moreover, WGW activated NLRP3 inflammasome, in which MAPK/NF-κB signaling pathway played an important role. These results indicated WGW might be a potential immuno-stimulation drug to promote inflammation.

Degradation of sulphated polysaccharides from Grateloupia livida and antioxidant activity of the degraded components

Degradation of sulphated polysaccharides from Grateloupia livida (GLP) was studied using H2O2-Vc combined with microwave treatment. Optimal conditions were determined after the Box-Behnken response surface analysis. The best degradation conditions were as follows: microwave power 250 W, microwave temperature 54 °C, the concentration of H2O2 3 mM, degradation time 33 min. Under these conditions, the DPPH scavenging activity of the degraded GLP (DGLP) was 71.39 ± 0.17% at a concentration of 6.0 mg/mL. The degradation method is fast and effective, which is beneficial to improve the antioxidant activity of polysaccharides.Two sulphated polysaccharide constituents (DGLP-1 and DGLP-2) were isolated from DGLP and characterized, and their antioxidant activities were determined. The two polysaccharides had high sulphate content (sulphate content: 25.18–25.26%), contained galactose as the major monosaccharide, and had molecular weights of 158.49 ± 0.43 and 18.06 ± 0.92 kDa, respectively. Antioxidant assays suggested that DGLP-1 and especially DGLP-2 possessed good antioxidant properties.

Structural analysis and anti-complement activity of polysaccharides extracted from Grateloupia livida (Harv.) Yamada

Polysaccharides were extracted from Grateloupia livida (Harv.) Yamada using hot water (extracted product denoted WGW) and then degraded in dilute sulfuric acid (degraded product denoted WGWD). The degraded mixture was then separated into four fractions through anion exchange chromatography on 2-diethylaminoethanol (DEAE)-Bio-Gel Agarose FF gel. Electrospray ionization collision-induced dissociation tandem mass spectrometry (ESI-CID-MS/MS) was performed to elucidate the structural features of all fractions. In combination with nuclear magnetic resonance spectroscopy (NMR) and infrared spectroscopy (IR) data, the major polysaccharide structures were concluded to be µ-carrageenan and κ-carrageenan. µ-Carrageenan usually has a backbone of alternating 1,3-linked s-D-galactopyranose residues sulfated at C-4 and 1-4-linked α-D-galactopyranose residues sulfated at C-6, while κ-carrageenan consists of alternating 1,3-linked s-D-galactopyranose residues sulfated at C-4 and 1,4-linked α-D-3,6-anhydrogalactopyranose residues. Trace v-carrageenan- composed of 1,3-linked s-D-galactopyranose residues sulfated at C-4 and 1,4-linked α-D-galactopyranose residues sulfated at C-2 and C-6, was also detected. Furthermore, the polysaccharide had a backbone comprising 1,3-linked s-D-galactopyranose and 1,4-linked α-L-galactopyranose sulfated at C-6, which is the agarose precursor. The hydroxy groups in the galactopyranose were partially substituted by methyl and pyruvic acid acetal (PA) groups. The anti-complementary activities of WGW and its derivatives against classical pathways were measured. The native polysaccharides in WGW had higher activities, while the derivatives had much weaker activities. This indicated that the molecular weight and sulfate content were important factors affecting the anti-complement activity.

Photosynthetic fluorescence characteristics of six macroalgae species in seaweed beds of Gouqi Island, Zhejiang, China.

The study of photosynthetic fluorescence characteristics of algae is important for the analy-sis of photosynthesis and carbon sequestration of algae. In July 2017, six common species of macroalgae found in Gouqi seaweed beds were collected, including Ulva pertusa, Cladophora stimpsonii, Grateloupia livida, Sargassum thunbergii, Polysiphonia urceolata, and Hizikia fusifarme. In the field, the maximal quantum yieids of photosystem2(Fv/Fm) and rapid curves (RLCs) were mea-sured by using pulse-amplitude modulated fluorometer (Diving-PAM). The results showed that the measured maximal quantum yields of U. pertusa, C. stimpsonii, G. livida, S. thunbergii, P. urceolata, and H. fusiforme were 0.702, 0.704, 0.457, 0.618, 0.421 and 0.567, respectively. The Fv'/Fm' of six species were in order of C. stimpsonii>U. pertusa>S. thunbergii＞H. fusiforme＞G. livida＞P. urceolata. The difference between each species and significant difference was found in U. pertusa, C. stimpsonii, and H. fusiforme. H. fusiforme, S. thunbergii and U. pertusa had higher Pm and α than other species, indicating their higher photosynthetic capacity and better adaptation in higher light condition. However, G. livida had higher α but lower Ik, indicating G. livida had higher photosynthetic capacity in low light condition. In a word, differences of photosynthetic capacity and light intense tolerance between the three phyla of macroalgae were found and we suggested H. fusiforme, S. thunbergii and U. pertusa had stronger photosynthetic capacity and light intense tolerance. Our results could provide theoretical basis for the seaweed bed conservation and carbon sequestration of macroalgae.

Purification, partial characterization and bioactivity of sulfated polysaccharides from Grateloupia livida

Purification, preliminary characterization and bioactivity of polysaccharides from Grateloupia livida (GL) were investigated. Three water-soluble sulfated polysaccharide fractions (GLP-1, GLP-2 and GLP-3) were isolated and purified from the edible and medicinal red seaweed, Grateloupia livida (Harv.) Yamada by DEAE Sepharose CL–6B and Sephadex G-100 column chromatography, and chemical characterization was performed by HPGPC, GC–MS, FT-IR and SEM. In addition, anticoagulant activities were determined by activated partial thromboplastin time (APTT), thrombin time (TT) and prothrombin time (PT) using normal human plasma in vitro. The antioxidant activities against DPPH and ABTS+ radicals were evaluated and compared. The molecular weights of GLP-1, GLP-2 and GLP-3 were 39.5, 60.4 and 3.36kDa, respectively. Monosaccharide analysis revealed that three polysaccharide fractions were homopolysaccharides and comprised of galactose only. Anticoagulant assays indicated that crude GLP, and purified GLP-1 and GLP-2 effectively prolonged APTT and TT, but not PT. All polysaccharide fractions exhibited significant in vitro antioxidant activities in a dose-dependent manner. GLP-2 showed consistently better anticoagulant and antioxidant activities compared with GLP, GLP-1 and GLP-3. These results demonstrate that sulfated polysaccharides isolated from Grateloupia livida can serve as readily available alternative natural sources of anticoagulant and antioxidant agents.

Growth, photosynthesis and nutrient uptake by Grateloupia livida (Halymeniales, Rhodophyta) in response to different carbon levels

:Grateloupia livida is a commercially important red macroalgal species. In the present study, thalli of G. livida, collected from Nan'ao Island, China, were cultured at different levels of CO2 (c. 1000, 390 and 50 ppm) to examine the growth and physiology and how its plasticity may affect photosynthesis at different carbon levels. The pH-drift experiments showed that G. livida could reach a final pH value of 9.75. Carbonic anhydrase (CA) activity was detected potentiometrically with both thalli and homogenates of G. livida. These implied that G. livida used HCO3− as a source of inorganic carbon for photosynthesis and that this was mediated by extracellular CA activity. Thalli of G. livida grown at low CO2 reduced the relative growth rate (RGR), both the PO43− and NO3− uptake rates, nitrate reductase activity and photochemical activity compared with the algae grown at ambient CO2. Moreover, the RGR and the initial slope of the rapid light curves (α) were inhibited by the high CO2 level in the seawater. The results indicated that either raised or lowered CO2 in culture were unfavourable environmental factors for growth and photosynthesis of G. livida.

Optimized Extraction of Polysaccharides from Grateloupia livida (Harv.) Yamada and Biological Activities.

Polysaccharides from Grateloupia livida (Harv.) Yamada (GL) were extracted by a heating circumfluence method. Single-factor experiments were performed for the three parameters: extraction time (X1), extraction temperature (X2) and the ratio of water to raw material (X3) and their test range. From preliminary experimental results, one type of the response surface methodology, the Box-Behnken design was applied for the optimizing polysaccharide extraction conditions. The experimental data obtained were fitted to a second-order polynomial equation. The optimal conditions were extraction time 5 h, extraction temperature 100 °C and ratio of water to raw material 70 mL/g. Under these conditions, the experimental yield was 39.22% ± 0.09%, which well matched the predicted value (39.25%), with 0.9774 coefficient of determination (R2). GL polysaccharides had scavenging activities for DPPH and hydroxyl radicals in vitro. The scavenging rates for both radicals peaked at 20 mg/mL GL concentration. However, the positive standard, VC (ascorbic acid), possessed stronger antioxidant activities than GL polysaccharides. Furthermore, the anticancer activity of GL polysaccharides on HepG2 cell proliferation increased dose- and time-dependently, but the positive standard, 5-fluorouracil (5-fu, showed more significant anticancer activity in this study. Overall, GL polysaccharides may have potential applications in the medical and food industries.

Effects of temperature and irradiance onearly development of Grateloupia livida

Effects of temperature and irradiance onearly development of Grateloupia livida

Antioxidant, antibacterial and antischistosomal activities of extracts from Grateloupia livida (Harv). Yamada.

The present study was designated to evaluate the antioxidant, antibacterial and antischistosomal activities of Grateloupia livida (GL) extracts in vitro. A GL Ethanol extract (EE) was separated into petroleum ether (PE), ethyl acetate (EA), n-butyl alcohol (BuOH) and aqueous (AQ) fractions to fractionate the polar and non-polar compounds in the EE. Extracts antioxidant activities were evaluated in vitro by DPPH radical-scavenging, deoxyribose radical scavenging, and β-carotene bleaching assays, all using butylated hydroxytoluene (BHT) as the reference antioxidant compound. The most effective antioxidant properties were observed in the PE fraction in all three assays. Antimicrobial testing showed that the PE fraction exhibited broad-spectrum antimicrobial activity, with the PE fraction also exhibiting strong activity against the human pathogenic trematode S. japonicum adult worm. In order to investigate the relationships between bioactivity and chemical composition, the chemical composition of the PE fraction was analyzed by gas chromatography-mass spectrometry (GC-MS). In total, 25 components were identified in the PE fraction, most of which have known antioxidant and antimicrobial activities. However, none of the compounds have reported activity against Schistosoma, suggesting that the schistosomicidal activity of the PE fraction may be related to minor constituents present in the extract, or governed by more intricate synergistic or additive relationships. Finally, fractions with the greatest biological activity displayed neither cellular cytotoxicity, at concentrations up to 100 ug/ml, or acute oral toxicity in mice, at doses up to 2000 mg/kg. Based on antioxidant, antimicrobial, antischistosomal activities, and low toxicity, the PE fraction possesses properties useful for food preservation and overall improvement of human health.

Carotenoid Profile of Edible Japanese Seaweeds: An Improved HPLC Method for Separation of Major Carotenoids

An improved multi-step gradient reverse phase high performance liquid chromatography (HPLC) method to simultaneously separate major carotenoids from natural as well as food samples was developed. Quantitative profiling of carotenoid compounds was carried out on three edible brown seaweeds (Sargassum horneri, Cystoseira hakodatensis, and Undaria pinnatifida) and three red seaweeds (Gracilaria vermiculophylla, Grateloupia asiatica, and Grateloupia livida). Fucoxanthin (Fx) was detected in all the brown seaweeds with quantities (mg g−1 dry weight [dwt]) ranging from 1.3 ± 0.3 in C. hakodatensis to 2.4 ± 0.1 in S. horneri. U. pinnatifida, commonly known as wakame, had a Fx content of 2.3 ± 0.1 mg g−1 dwt. In the case of red seaweeds, zeaxanthin (Zx) was the major carotenoid, and G. vermiculophylla had the highest Zx content (80.2 μg g−1 dwt) among the red seaweeds apart from small amounts of Fx (9.1 μg g−1 dwt). Similarly, the other two species of red seaweeds, G. asiatica and G. livida, contained (μg g−1 dwt) lutein (Lut), Fx, and Zx as the major carotenoids (G. asiatica: Lut 10.4, Fx 1.5, Zx 1.1; G. livida: Lut 9.3, Fx 3.5, Zx 1.0). The results suggest the usefulness of edible varieties (barring wakame) of seaweeds as dietary sources of carotenoids.

Isolations and structures of new ureido amino acids, lividine and grateloupine, from red algae O grateloupia c. agardh genus

Two new ureido amino acids, lividine ( 1) and grateloupine ( 2), were isolated from Grateloupia livida and Grateloupia filicina respectively. The structures of both amino acids were assumed mainly by NMR spectra and determined as N w -carbamoyl-L-citrulline for lividine and as N-carbamoyl- Y-aminobutyric acid for grateloupine by comparison with the synthetic compounds respectively.

紅藻ヒラムカデのd-2-hydroxy-3-aminopropane sulfonic acidと3-aminopropane sulfonic acidについて

The occurrence of d-2-hydroxy-3-aminopropane sulfonic acid and 3-aminopropane sulfonic acid in the methanolic extractives of Grateloupia livida was established. The authors wish to express here their thanks to Prof. Y. HASHIMOTO, Tokyo University for his suggestion and advice they received in the cource of this work.