Showing papers on "Kappaphycus alvarezii published in 2016"
TL;DR: A simple, rapid, and eco-friendly green method was introduced to synthesize magnetite nanoparticles (Fe3O4-NPs) successfully and two characteristic absorption peaks were observed at 556 and 423 cm−1, which proved the existence of Fe3O 4 in the prepared nanoparticles.
Abstract: In this study, a simple, rapid, and eco-friendly green method was introduced to synthesize magnetite nanoparticles (Fe3O4-NPs) successfully. Seaweed Kappaphycus alvarezii (K. alvarezii) was employed as a green reducing and stabilizing agents. The synthesized Fe3O4-NPs were characterized with X-ray diffraction (XRD), ultraviolet-visible spectroscopy (UV-Vis), Fourier transform infrared (FT-IR), and transmission electron microscopy (TEM) techniques. The X-ray diffraction planes at (220), (311), (400), (422), (511), (440), and (533) were corresponding to the standard Fe3O4 patterns, which showed the high purity and crystallinity of Fe3O4-NPs had been synthesized. Based on FT-IR analysis, two characteristic absorption peaks were observed at 556 and 423 cm−1, which proved the existence of Fe3O4 in the prepared nanoparticles. TEM image displayed the synthesized Fe3O4-NPs were mostly in spherical shape with an average size of 14.7 nm.
306 citations
TL;DR: Three different deep eutectic solvents prepared by the complexation of choline chloride with urea, ethylene glycol and glycerol along with their hydrated counterparts were used for the selective extraction of κ-carrageenan from Kappaphycus alvarezii to find the hydrated ones were found to be more effective in comparison to their non-hydrated counterparts.
110 citations
TL;DR: The biorefinery of carrageenan derived from processing of experimental strains of the red macroalgae Kappaphycus alvarezii can be exploited not only to produce carrageENan, but also to generate glucose for future use in biofuel production.
Abstract: Biorefineries serve to efficiently utilize biomass and their by-products. Algal biorefineries are designed to generate bioproducts for commercial use. Due to the high carbohydrate content of algal biomass, biorefinery to generate biofuels, such as bioethanol, is of great interest. Carrageenan is a predominant polysaccharide hydrocolloid found in red macroalgae and is widely used in food, cosmetics, and pharmaceuticals. In this study, we report the biorefinery of carrageenan derived from processing of experimental strains of the red macroalgae Kappaphycus alvarezii. Specifically, the chemical composition and enzymatic hydrolysis of the residue produced from carrageenan extraction were evaluated to determine the conditions for efficient generation of carbohydrate bioproducts. The productivity and growth rates of K. alvarezii strains were assessed along with the chemical composition (total carbohydrates, ash, sulfate groups, proteins, insoluble aromatics, galacturonic acid, and lipids) of each strain. Two strains, brown and red, were selected based on their high growth rates and productivity and were treated with 6 % KOH for extraction of carrageenan. The yields of biomass from treatment with 6 % KOH solution of the brown and red strains were 89.3 and 89.5 %, respectively. The yields of carrageenan and its residue were 63.5 and 23 %, respectively, for the brown strain and 60 and 27.8 %, respectively, for the red strain. The residues from the brown and red strains were assessed to detect any potential bioproducts. The galactan, ash, protein, insoluble aromatics, and sulfate groups of the residue were reduced to comparable extents for the two strains. However, KOH treatment did not reduce the content of glucan in the residue from either strain. Glucose was produced by enzymatic hydrolysis for 72 h using both strains. The glucan conversion was 100 % for both strains, and the concentrations of glucose from the brown and red strains were 13.7 and 11.5 g L−1, respectively. The present results highlight the efficiency of generating a key bioproduct from carrageenan residue. This study demonstrates the potential for glucose production using carrageenan residue. Thus, the biorefinery of K. alvarezii can be exploited not only to produce carrageenan, but also to generate glucose for future use in biofuel production.
92 citations
TL;DR: Significant increase in P and K content in grains was observed through G-sap application, suggesting bio-stimulation in absorption of these elements, and stover yield production at reduced RRF in certain combinations with sap was at par with T1 suggesting a possible saving on fertilizer requirement for fodder production under rain-fed conditions.
Abstract: The present study aimed to assess not only the efficacy of sap from two seaweeds Kappaphycus alvarezii (K-sap) and Gracilaria edulis (G-sap) on productivity and quality of Zea mays under rain-fed condition, but also to quantify whether sap application is beneficial in terms of lowering the carbon and phosphate footprint of mineral fertilizers per unit of produce. Field experiment was carried out to test 18 treatments, viz., 5 concentrations (2.5, 5.0, 7.5, 10 and 15 %) each of K-sap and G-sap applied along with recommended rate of fertilizers (RRF); 3 concentrations (7.5, 10 and 15 %) of each of the two types of sap applied along with 50 % RRF; alongside 2 control treatments T1 (water spray along with 100 % RRF) and T18 (water spray along with 50 % RRF). The optimal treatments that enhanced the grain productivity of maize were 5 % G-sap or 7.5 % K-sap applied in conjunction with 100 % RRF and the grain yield enhancements ranged from 21.4 to 29.8 % as compared to T1. Significant increase in P (35.5 %) and K (14.4 %) content in grains was observed through G-sap application, suggesting bio-stimulation in absorption of these elements. Notably, stover yield production at reduced RRF in certain combinations with sap was at par with T1 suggesting a possible saving on fertilizer requirement for fodder production under rain-fed conditions. Compared to T1, there was marked reduction of 17.5 and 23.1 % in global warming potential per unit of produce when 7.5 % K-sap and 5 % G-sap were used respectively in conjunction with 100 % RRF.
59 citations
TL;DR: Results indicated the beneficial effect of native and commercial carrageenans as anticancer agents being a free radical scavenger and anti-diabetic property of both Carrageenan showed inhibition effect on α- glucosidase enzyme.
56 citations
TL;DR: In this article, the effect of KCl on characteristic of refined κ-carrageenan extracted from the red algae has been determined, which indicated that higher KCl concentration resulted in the increase of the carrageenan yield, ash and sulphate content, and the decrease of gel strength, moisture and acid-insoluble ash content.
54 citations
TL;DR: In this article, the proximate composition, phytochemical and antioxidant activity of Kappaphycus alvarezii, under different drying conditions, namely, oven dried, sun dried, vacuum dried, and freeze dried, were determined.
Abstract: This study determined the proximate composition, phytochemical and antioxidant activity of the edible red seaweed, Kappaphycus alvarezii, under different drying conditions, namely, oven dried, sun dried, vacuum dried, and freeze dried. The proximate composition of K. alvarezii has shown no significant difference (p > 0.05) in macronutrient components except fat content. Phytochemical studies conducted on total phenolic content and total flavonoid content showed that vacuum-dried extracts demonstrated the highest total phenolic content at 12.97 mg PGE g−1 DE. In vitro antioxidant activities of seaweed extract by ferric-reducing antioxidant potential and 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity proved that oven-dried extracts showed the highest ferric-reducing antioxidant power value, 272.95 µM TE mg−1, and highest scavenging activity, EC50 9.55 mg mL−1. In general, sun-dried extracts showed lowest antioxidant among all treatments.
38 citations
TL;DR: The phytohormone levels and transcript regulation of defence-related genes were studied in tomato seedlings in response to K-sap application alone and in combination with the fungus Macrophomina phaseolina, the causal agent of charcoal rot in tomato.
Abstract: Seaweeds, an integral part of marine coastal environment, are an important food, industrial raw materials and biostimulants for crop growth due to the presence of a number of plant growth stimulants. The sap of an economically important seaweed Kappaphycus alvarezii (K-sap) is gaining momentum for sustainable intensification of agricultural productivity. In the present study, the phytohormone levels and transcript regulation of defence-related genes were studied in tomato seedlings in response to K-sap application alone and in combination with the fungus Macrophomina phaseolina, the causal agent of charcoal rot in tomato. The application of K-sap alone and in combination with fungus M. phaseolina significantly increased the concentration of ABA, IAA, SA and zeatin hormones. The enhanced transcript of pathogenesis related genes (PR-1b1, PR-3 and PR-5) was observed in response to application of K-sap alone and in combination with fungus M. phaseolina in tomato. The transcription factor, Pti4 and mitogen-activated kinase pathway gene, MPK2 also showed transcript accumulation on combined treatment of Macrophomina and K-sap. This is the first report highlighting the differential regulation of defence-related genes in accordance with phytohormone levels on application of seaweed sap.
36 citations
TL;DR: In this paper, a green approach using ultrasound irradiation as the reducing agent and seaweed Kappaphycus alvarezii (K. alvarisii) as the natural bio-media was proposed.
Abstract: Green methods are a safer alternative to natural chemical and physical methods for the synthesis of silver nanoparticles (Ag-NPs), due to their being environmentally friendly and cost effective. This study offers a new green approach using ultrasound irradiation as the reducing agent and seaweed Kappaphycus alvarezii (K. alvarezii) as the natural bio-media. The seaweed K. alvarezii/Ag-NPs was characterised by ultraviolet–visible (UV–vis), X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscope with energy dispersive X-ray (FESEM-EDX), zeta potential, and Fourier transform infrared (FTIR) studies. UV–vis shows that surface plasmon resonance (SPR) arises from this solution due to the combined oscillations from the nanoparticles. The XRD study indicates the crystalline nature of the Ag-NPs. From the TEM images, the Ag-NPs are almost spherical with an average diameter of 11.78 nm. The FTIR spectrum provides adequate evidence of phytochemicals stabilising the nanoparticles. Synthesised Ag-NPs were successfully obtained using this green method.
36 citations
TL;DR: The platform-chemicals and sugar production from the macro-algae, Kappaphycus alvarezii, were investigated by dilute-acid-catalyzed hydrothermal reaction and the respective optimal yields were found.
Abstract: In this study, the platform-chemicals and sugar production from the macro-algae, Kappaphycus alvarezii , were investigated. The production of glucose, galactose, levulinic acid (LA), and 5-hydroxymethylfurfural (5-HMF) was evaluated by dilute-acid-catalyzed hydrothermal reaction. By this approach, the respective optimal yields (and reaction conditions) were as follows: glucose 2.15 g/L (reaction temperature: 160 °C, catalyst amount: 1.09%, reaction time: 20 min), galactose 14.47 g/L (160.3 °C, 1.02%, 20.3 min), LA 11.69 g/L (178.2 °C, 2.87%, 39.3 min) and 5-HMF 3.02 g/L (160.6 °C, 1%, 20.1 min).
34 citations
TL;DR: Overnight incident irradiance on the frond under fine clear sky might be too strong for the effective photosynthesis of this species, suggesting that optimum irradiance for gross photosynthesis with the minimum decline of ΦPSII seems to be much lower.
Abstract: The effect of irradiance and temperature on the photosynthesis and growth of a Vietnamese-cultivated red alga, Kappaphycus alvarezii, was determined by laboratory and field measurements. Dissolved oxygen sensors and pulse amplitude modulated (PAM) fluorometry were used for the measurements of photosynthetic efficiency. A Diving-PAM revealed that in situ measurements of the effective quantum yield (ΦPSII) were negatively correlated with incident irradiance. ΦPSII decreased as irradiance increased at noon and recovered in the evening, suggesting photo-inhibition. A model of the net photosynthesis–irradiance (P-E) relationship determined in a laboratory experiment at 26 °C revealed that the net photosynthetic rate quickly increased at irradiances below the estimated saturation irradiance of 154 μmol photons m−2 s−1 (95 % Bayesian credible interval (BCI) of 117–203 μmol photons m−2 s−1). Gross photosynthesis and dark respiration under the laboratory measurements were also determined over a range of temperatures (8–42 °C), revealing that the gross photosynthetic rates of 8.0 (BCI 7.03–9.59) μg O2 gww−1 min−1 at 31.1 (BCI 30.2–32.0)°C, and the dark respiration rate increased exponentially from a low of 0.22 μg O2 gww−1 min−1 at 10 °C to a high of 1.88 μg O2 gww−1 min−1 at 42 °C. The estimated highest value of the maximum quantum yield (ΦPSII at 0 μmol photons m−2 s−1 = Fv/Fm) determined with the Imaging-PAM and occurred at 22.2 (BCI 20.8–23.5)°C and was 0.51 (BCI 0.48–0.54). Relative growth rate (RGR) and the survival rate after 2 weeks of laboratory culture showed that the relatively high growth rates (ca. 1.5 %) occurred at 28 and 32 °C; however, mortality was 100 % at 36 °C. This species is considered to be well-adapted to the natural temperature range of study site; however, it is likely close to the marginal temperature conditions. Furthermore, daytime incident irradiance on the frond under fine clear sky might be too strong for the effective photosynthesis of this species, suggesting that optimum irradiance for gross photosynthesis with the minimum decline of ΦPSII seems to be much lower.
TL;DR: The recombinant proteins would be useful as antiviral reagents targeting the viral surface glycoproteins with high-mannose N-glycans, and the cultivated alga K. alvarezii could also be a good source of not only carrageenans but also this functional lectin(s).
Abstract: We previously reported that a high-mannose binding lectin KAA-2 from the red alga Kappaphycus alvarezii, which is an economically important species and widely cultivated as a source of carrageenans, had a potent anti-influenza virus activity. In this study, the full-length sequences of two KAA isoforms, KAA-1 and KAA-2, were elucidated by a combination of peptide mapping and complementary DNA (cDNA) cloning. They consisted of four internal tandem-repeated domains, which are conserved in high-mannose specific lectins from lower organisms, including a cyanobacterium Oscillatoria agardhii and a red alga Eucheuma serra. Using an Escherichia coli expression system, an active recombinant form of KAA-1 (His-tagged rKAA-1) was successfully generated in the yield of 115 mg per liter of culture. In a detailed oligosaccharide binding analysis by a centrifugal ultrafiltration-HPLC method with 27 pyridylaminated oligosaccharides, His-tagged rKAA-1 and rKAA-1 specifically bound to high-mannose N-glycans with an exposed α1-3 mannose in the D2 arm as the native lectin did. Predicted from oligosaccharide binding specificity, a surface plasmon resonance analysis revealed that the recombinants exhibit strong interaction with gp120, a heavily glycosylated envelope glycoprotein of HIV with high association constants (1.48 - 1.61 × 10(9) M(-1)). Native KAAs and the recombinants inhibited the HIV-1 entry at IC50s of low nanomolar levels (7.3-12.9 nM). Thus, the recombinant proteins would be useful as antiviral reagents targeting the viral surface glycoproteins with high-mannose N-glycans, and the cultivated alga K. alvarezii could also be a good source of not only carrageenans but also this functional lectin(s).
TL;DR: The structure and ultrastructure of the stages observed in the life cycle of Polysiphonia sp.
Abstract: With the increase of seaweed farming activities, epiphytic filamentous algae (EFA) disease has appeared in many regions of Madagascar. This infestation has dramatic consequences for local farmers as it alters drastically farmed algal growth and has caused farming activity to collapse in many places. The present study characterizes the structure and ultrastructure of the stages observed in the life cycle of Polysiphonia sp. and gives the results of a monitoring of 18 months made in three Kappaphycus alvarezii farming sites in the southwest of Madagascar. Transmission electron microscopy (TEM) was used to analyze the ultrastructure of the cortex in infested K. alvarezii. Five stages have been observed in the life cycle of Polysiphonia sp.: the infesting stage that is a small dark spot observed at the surface of K. alvarezii, the male gametophyte, the female gametophyte, the tetrasporocysts, and the undifferentiated stage where individuals show normal thalli without sexual differentiation. EFA infestation was never recorded in Sarodrano, but often in the two other monitored villages (Lambohara, Tampolove). Prevalence of infestation varied from 40 to 100 % and the rates of infestation from 42 to 78 epiphytes cm−2. Prevalence of infestation showed significant seasonal variation and a between-sites variation; the rates of infestation were not significantly different between sites and did not vary with the period. The ways of infestation between K. alvarezii individuals in an infested field and from infested to healthy fields are discussed at the light of the present results.
TL;DR: Development of the HT acid hydrolysis process and adapted yeast could enhance the overall ethanol fermentation yields of K. alvarezii seaweed.
TL;DR: Photosynthetic rates increased with decreasing pH, revealing K. alvarezii’s ability to modify its photosynthetic affinity for acidic seawater conditions; yet, their underlying mechanism of response to pH shifts still need to be further examined.
Abstract: Understanding the physiological condition of seaweeds as influenced by biotic and abiotic stress is vital from the perspective of massive expansion and sustainability of seaweed-based industries. The photosynthetic responses of Neosiphonia sp. epiphyte-infected (INF) and healthy (HEA) Kappaphycus alvarezii under various combinations of irradiance, salinity and pH were studied using photosynthesis-irradiance (P-E) curves. Measurements of algal photosynthetic rates, expressed in terms of amount of oxygen production per fresh weight biomass per unit time (mg O2 g−1 FW h−1), were carried out using the light-dark bottle technique. Neosiphonia-infected K. alvarezii (INF) had lower photosynthetic rates than healthy ones (HEA). Similarities (p > 0.05) in light-saturated photosynthesis rates (P
max) and significant differences (p < 0.05) in initial slope of curve (α) between INF and HEA K. alvarezii suggest that both samples are adapted to similar light conditions and differs only on photosynthetic efficiency. Low P
max (0.7–2.0 mg O2 g−1 FW h−1) and high initial saturation irradiances (E
k
= 90–519 μmol photons m−2 s−1) of INF seaweeds resulted to their low photosynthetic efficiency (α = 0.002–0.010). Such decline in α is attributed to the epiphyte, as Neosiphonia sp. covered almost the entire surface of K. alvarezii. An increase in chlorophyll-a (35–42.1 vs. 27.7–31.5 μg g−1 FW, HEA) and phycobilin (1.96–2.39 vs. 1.16–1.58 mg g−1 FW, HEA) contents was also observed in INF samples, suggesting acclimation to low-irradiance conditions, as a result of competition for light between the epiphyte and host. Both INF and HEA K. alvarezii also exhibited broad photosynthetic tolerance to short-term changes in irradiance, with no photoinhibition at the highest irradiance of 850 μmol photons m−2 s−1. K. alvarezii had a euryhaline photosynthetic response, with optimum salinity of 35 psu. Photosynthetic rates increased with decreasing pH, revealing K. alvarezii’s ability to modify its photosynthetic affinity for acidic seawater conditions; yet, their underlying mechanism of response to pH shifts still need to be further examined.
TL;DR: Using langmuir isotherm model, Cu(II) had the highest affinity for waste seaweeds with the highest qmax and electronegativity values among three heavy metals.
Abstract: The objective of this study was to evaluate ethanol production and bioadsorption with four red seaweeds, Gelidium amansii, Gracilaria verrucosa, Kappaphycus alvarezii and Eucheuma denticulatum. To produce ethanol, thermal acid hydrolysis, enzymatic saccharification and fermentation was carried out. After pretreatment, 38.5, 39.9, 31.0 and 27.5 g/L of monosaccharides were obtained from G. amansii, G. verrucosa, K. alvarezii and E. denticulatum, respectively. Ethanol fermentation was performed with Saccharomyces cerevisiae KCCM 1129 adapted to 80 g/L galactose. The ethanol productions by G. amansii, G. verrucosa, K. alvarezii and E. denticulatum were 18.8 g/L with Y EtOH = 0.49, 19.1 g/L with Y EtOH = 0.48, 14.5 g/L with Y EtOH = 0.47 and 13.0 g/L with Y EtOH = 0.47, respectively. The waste seaweed slurries after the ethanol fermentation were reused to adsorb Cd(II), Pb(II) and Cu(II). Using langmuir isotherm model, Cu(II) had the highest affinity for waste seaweeds with the highest q max and electronegativity values among three heavy metals.
TL;DR: It was concluded that AMPEP was efficient against epibiont settlement on K. alvarezii cultivated on tubular nets tied on floating rafts maintaining favorable commercial results for carrageenan yield.
Abstract: Acadian marine plant extract powder (AMPEP), a product derived from Ascophyllum nodosum, has been widely used as a plant growth stimulant and recently has been tested on seaweeds with successful results on increasing growth and preventing epibiosis in Kappaphycus alvarezii cultivation. Although, the AMPEP ability to deal with epibiosis on seedlings cultivated in tubular nets and its commercial implications are still unknown. Between July 2012 and September 2013, three sampling periods were randomly selected at a Brazilian commercial farm in order to evaluate the effect of AMPEP on K. alvarezii daily growth rate, carrageenan yield and quality, and epibiont settling. Ten tubular nets containing three 100 g seedlings each (five treated with AMPEP and five not) were tied on floating rafts. Control samples displayed higher biomass of epibionts [0.76 ± 0.52 g (dry mass) tubular net−1] when compared to the AMPEP-treated samples [0.26 ± 0.27 g (dry mass) tubular net−1]. Carrageenan yield (44.65 ± 7.09 %) showed no significant difference between treatments (t = 0.46; p = 0.64), with larger percentages by the end of the third sampling period (F = 130.96, p < 0.001). When comparing AMPEP treatment with the control, carrageenan gel strength (252.14 ± 82.4 g cm−3) and viscosity (106.72 ± 45.11 cP) showed opposite results. The gel strength of AMPEP-treated samples was higher than their controls (t = 2.88; p = 0.007), while the gel viscosity of samples treated with AMPEP was lower than samples from their control (t = −2.4; p = 0.02). K. alvarezii daily growth rates between treatments were not different (t = 0.92; p = 0.36), exhibiting low commercial values probably due to herbivory. It was concluded that AMPEP was efficient against epibiont settlement on K. alvarezii cultivated on tubular nets tied on floating rafts maintaining favorable commercial results for carrageenan yield.
TL;DR: The results showed that mass selection method could be used to produce high growth of seed, and kinetin and indole-3-acetic acid play an important role in growth of K. alvarezii.
Abstract: The use of high quality seed can support the success of the seaweed cultivation. This study was conducted to evaluate the growth performance, morphology and growth related hormone level of brown strain seaweed Kappaphycus alvarezii seed produced by mass selection. Selection was performed in the Tomini Gulf, Gorontalo, based on mass selection of seaweed seed protocol with a slight modification in cut-off 10% of the highest daily growth rate. Selection was carried out for four generations. The selected 4thgeneration of seed was then used in cultivation performance test in the Celebes Sea, North Gorontalo, for three production cycles. The results showed that the selected K. alvarezii has higher clump weight and daily growth rate, longer thallus, more number of branches, and shorter internodes compared to the unselected control and seaweed from the farmer as external control. Furthermore, total sugar content, levels of kinetin hormone and kinetin:indole-3-acetic acid ratio were higher in selected seaweeds than that of unselected control and external control. Thus, mass selection method could be used to produce high growth of seed, and kinetin and indole-3-acetic acid play an important role in growth of K. alvarezii.
TL;DR: A bioeconomic model for individual and artisanal culture of Kappaphycus alvarezii is constructed and suggests that this type of culture can fulfill an important social role as long as conflicts for marine space usage are resolved, climate conditions are favorable, and diseases and epiphytes are controlled.
Abstract: Commercial culture of red algal seaweeds, particularly Kappaphycus and Eucheuma, has increased significantly in recent years and, since 2008, has surpassed the production of all other farmed seaweeds. A number of countries have analyzed the feasibility of small-scale culture of Kappaphycus as a method of alleviating poverty in low-income coastal communities. In this study, a bioeconomic model for individual and artisanal culture of Kappaphycus alvarezii is constructed. The results of the study show that using the base model, the net present value is positive at the 6-month mark, once the business has started, and that the internal return rate is 210 %. These results are explained by the small investment required for a raft culture system. Sensitivity analysis shows that the business tolerates important unfavorable variations in the critical economical, technological, and biological variables. Finally, the results suggest that this type of culture can fulfill an important social role as long as conflicts for marine space usage are resolved, climate conditions are favorable, and diseases and epiphytes are controlled.
TL;DR: In this paper, Kappaphycus alvarezii Doty (Doty) was analyzed for its dryweed quality (moisture and clean anhydrous weed (CAW) contents), carrageenan yield, and gel strength with respect to environmental parameters (seawater temperature, salinity, nitrate, and phosphate) for 1 year from April 2012 to March 2013.
Abstract: Cultivated Kappaphycus alvarezii Doty (Doty) was analyzed for its dryweed quality (moisture and clean anhydrous weed (CAW) contents), carrageenan (semi-refined carrageenan (SRC)) yield, and gel strength with respect to environmental parameters (seawater temperature, salinity, nitrate, and phosphate) for 1 year from April 2012 to March 2013 from three different localities, viz., Mangadu, Munaikadu, and Vedalai, located in Palk Bay, Ramanathapuram District, Tamil Nadu, Southeast coast of India. Dryweed quality, viz., moisture content (35.00 ± 0.00 to 38.39 ± 0.19 %), clean anhydrous weed (39.26 ± 1.37 to 45.22 ± 0.57 %), and carrageenan (SRC) yield (33.30 ± 1.23 to 38.50 ± 0.20 to 0.30 %) with gel strength (379.05 ± 6.07 to 486.44 ± 5.57 g cm−2), was found to vary differently at all the sites during the study period. Two-way ANOVA showed that seawater temperature, salinity, and nitrate were significant spatially, while carrageenan (SRC) yield and gel strength were found to be significant (p = 0.05 level) both spatially and temporally. The carrageenan (SRC) obtained in this study met international specifications with respect to dryweed quality, carrageenan yield, and gel strength, suggesting its production indigenously for internal consumption as well as for export using the cultivated raw material and thus providing employment to the coastal rural people in India and earning foreign exchange.
TL;DR: Results indicate that the aquaculturable carrageenan producer K. alvarezii might be a promising source of neurotrophic compounds to enhance memory and learning.
Abstract: Neurodegenerative disorders, which affect memory, cognition, and social functions, can be treated using neurotrophic agents to support neuronal development and protect mature neurons from atrophy. We screened 34 tropical seaweed species collected from Indonesian coastal areas for their neurite-outgrowth-promoting activity (NOPA) in fetal rat hippocampal neurons in vitro. Based on the number and total length of primary neurites, red seaweeds had greater NOPA than green and brown seaweeds. The red seaweed Kappaphycus alvarezii showed the highest NOPA. Addition of the ethanol extract to the culture (1 μg mL−1) significantly accelerated initial neuronal maturation from stage I to stage II (70 %; P < 0.05) within 24 h and increased the number of neurites that developed multipolar characteristics (48 %; P < 0.05). These results indicate that the aquaculturable carrageenan producer K. alvarezii might be a promising source of neurotrophic compounds to enhance memory and learning.
TL;DR: The feasibility of cultivating K. alvarezii on the northwest coast of India was confirmed and the average daily growth rates were confirmed.
Abstract: Cultivation of Kappaphycus alvarezii was carried out at Okha, northwest coast of India, from August 2004 to April 2006, using the raft and net bag methods. Seawater temperature, salinity, nitrate, and phosphate varied seasonally, with average values of 26.51 ± 1.72 °C, 34.23 ± 1.79 ‰, 17.46 ± 8.77 μM L−1, and 1.32 ± 0.78 μM L−1, respectively. After 15, 30, and 45 days of growth, average daily growth rates (DGRs) were 6.87 ± 0.27, 5.99 ± 0.18, and 4.97 ± 0.08 % with corresponding biomass of 292.43 ± 12.06, 629.58 ± 32.56, and 977.98 ± 36.59 g FW plant−1, respectively, for the raft cultivation. In the net bag method, after 15, 30, and 45 days of growth, the mean DGRs were 7.88 ± 0.38, 5.83 ± 0.10, and 4.42 ± 0.14 % with biomass values of 348.98 ± 19.48, 623.28 ± 29.95, and 813.73 ± 52.64 g FW plant−1, respectively. This study confirmed the feasibility of cultivating K. alvarezii on the northwest coast of India.
TL;DR: Bioethanol was produced from Kappaphycus alvarezii seaweed biomass using separate hydrolysis and fermentation (SHF) and the highest ethanol concentration was 15.3%, which was obtained using adapted S. cerevisiae.
Abstract: Bioethanol was produced from Kappaphycus alvarezii seaweed biomass using separate hydrolysis and fermentation (SHF). Pretreatment was evaluated for 60 min at 121°C using 12% (w/v) biomass slurry with 364 mM H2SO4. Enzymatic saccharification was then carried out at 45°C for 48 h using Celluclast 1.5 L. Ethanol fermentation with 12% (w/v) K. alvarezii hydrolyzate was performed using the yeasts Saccharomyces cerevisiae KCTC1126, Kluyveromyces marxianus KCTC7150, and Candida lusitaniae ATCC42720 with or without prior adaptation to high concentrations of galactose. When non-adapted S. cerevisiae, K. marxianus, and C. lusitaniae were used, 11.5 g/l, 6.7 g/l, and 6.0 g/l of ethanol were produced, respectively. When adapted S. cerevisiae, K. marxianus, and C. lusitaniae were used, 15.8 g/l, 11.6 g/l, and 13.4 g/l of ethanol were obtained, respectively. The highest ethanol concentration was 15.8 g/l, with YEtOH = 0.43 and YT% = 84.3%, which was obtained using adapted S. cerevisiae.
TL;DR: In this paper, the removal of a cationic dye (crystal violet) from aqueous solution by two red seaweeds (Gracilaria edulis and Kappaphycus alvarezii) under different environmental conditions was investigated.
Abstract: The removal of a cationic dye (crystal violet) from aqueous solution by two red seaweeds (Gracilaria edulis and Kappaphycus alvarezii) under different environmental conditions was investigated. Biosorption of crystal violet was studied by varying particle size (0.712–2.36 mm), biomass dosage (2–8 g/L), solution pH (2–9), initial dye concentration (50–1,000 mg/L) and contact time (0–360 min). At optimum seaweed particle size (1.18 mm), seaweed dosage (5 g/L), equilibrium pH (8), initial dye concentration (100 mg/L) and equilibrium time (360 min), G. edulis and K. alvarezii recorded crystal violet uptakes of 181.0 and 171.9 mg/g, respectively. The kinetic data obtained at different initial crystal violet concentrations indicated that biosorption rate was fast for both seaweeds and the data were successfully modelled using the pseudo-first and pseudo-second-order models. The Langmuir, Freundlich and Redlich–Peterson and Sips models were used to describe the crystal violet isotherm data; of which the ...
TL;DR: The findings indicate the ability of Kappaphycus to grow well in land-based cultivation system which can be further explored to support the development of local seaweed farming industry especially for the high-quality seed production.
Abstract: The study was conducted to determine the growth and biochemical composition of Kappaphycus cultivated in a customized tank culture system. Two red seaweed species (Kappaphycus alvarezii and Kappaphycus striatum) were selected and cultivated using suspension culture method in the tank. Three cycles of 40-day culture trials were performed during September to December 2014, and both K. alvarezii and K. striatum were successfully grown in the tank. This is the first report on the success of seaweed culture in Malaysia involving land-based facility. Interestingly, K. striatum was found to grow better than K. alvarezii in the tank. The daily growth rate (DGR) and daily weight productivity (DWP) of K. alvarezii ranged from 1.96 ± 0.08 to 2.29 ± 0.11 % day−1 and 3.70 ± 0.20 to 4.55 ± 0.34 g DW m−2 day−1, and those of K. striatum ranged from 2.25 ± 0.06 to 2.96 ± 0.02 % day−1 and 4.48 ± 0.19 to 6.17 ± 0.18 g DW m−2 day−1, respectively. These values were influenced by the changes in the water quality variables during the culture period. On the other hand, the biochemical composition of K. alvarezii and K. striatum was not significantly different (p > 0.05) from each other. Both growth and biochemical composition of K. alvarezii and K. striatum in the present study were comparable with those cultured in the open sea. In conclusion, the findings indicate the ability of Kappaphycus to grow well in land-based cultivation system which can be further explored to support the development of local seaweed farming industry especially for the high-quality seed production.
TL;DR: It is concluded that K. alvarezii has greater tolerance to low temperature than K. striatum, and both the maximal efficiency of PSII photochemistry and the performance index decreased significantly in K.striatum, indicating that the photosynthetic apparatus was damaged at 23 °C.
Abstract: Kappaphycus are farmed in tropical countries as raw material for carrageenan, which is widely used in food industry. The sea area available for farming is one limiting factor in the production of seaweeds. Though cultivation is spreading into subtropical regions, the lower seawater temperature is an important problem encountered in subtropical regions for the farming of Kappaphycus. This research of physiological response to low temperature stress will be helpful for screening Kappaphycus strains for growth in a lower temperature environment. Responses of antioxidant systems and photosystem II (PSII) behaviors in Kappaphycus alvarezii and Kappaphycus striatum were evaluated during low temperature treatments (23, 20, 17 °C). Compared with the controls at 26 °C, the H2O2 concentrations increased in both species when the thalli were exposed to low temperatures (23, 20, 17 °C), but these increases were much greater in K. striatum than in K. alvarezii thalli, suggesting that K. striatum suffered more oxidative stress. The activities of some important antioxidant enzymes (e.g. superoxide dismutase and ascorbate peroxidase) and the hydroxyl free radical scavenging capacity were substantially higher at 23, 20 and 17 °C than at the control 26 °C in K. alvarezii, indicating that the antioxidant system of K. alvarezii enhanced its resistance to low temperature. However, no significant increases of antioxidant enzymes activities were observed at 20 and 17 °C in K. striatum. In addition, both the maximal efficiency of PSII photochemistry (FV/Fm) and the performance index (PIABS) decreased significantly in K. striatum at 23 °C, indicating that the photosynthetic apparatus was damaged at 23 °C. In contrast, no significant decreases of either FV/Fm or PIABS were observed in K. alvarezii at 23 °C. It is concluded that K. alvarezii has greater tolerance to low temperature than K. striatum.
TL;DR: In this paper, the authors showed that the addition of the red seaweeds Hypnea musciformis, Kappaphycus alvarezii, and Jania rubens with great antioxidant potential significantly increased the oxidative stability of the refined sardine oil.
Abstract: The aim of this study was to prepare the refined oil derived from Sardinella longiceps by a step-wise procedure of degumming, bleaching, and deodorization. The refined sardine oil showed greater susceptibility toward oxidation than the crude oil, but the addition of ethyl acetate fractions of the red seaweeds Hypnea musciformis, Kappaphycus alvarezii, and Jania rubens with great antioxidant potential significantly increased the oxidative stability of the refined oil. The refined oil supplemented with the ethyl acetate fraction of these seaweeds indicated more noteworthy oxidative stability indices (≥ 0. 51 h) than α-tocopherol. The induction time was greater for refined oil added with H. musciformis (1.26 h) than butylated hydroxytoluene (1.04 h) and α-tocopherol (0.4 h). No traces of aromatic (δ 6.7–7.5 ppm), hydroperoxides, and aldehydes (δ 9–10 ppm) in the 1H-NMR spectra of the refined oil supplemented with seaweed extracts at the baseline and after the accelerated storage study demonstrated th...
TL;DR: Under low temperature stress, the maximum quantum yield of PSII photochemistry (FV/FM) and PSII actual photochemical efficiency (ΦPSII) decreased in K. alvarezii thalli, suggesting that the photosynthetic capacity declined.
Abstract: To understand the effects of low temperature stress on Kappaphycus alvarezii and the responses of antioxidant systems and photosystem II (PSII), behaviour in K. alvarezii thalli exposed to low temp...
12 Aug 2016
TL;DR: The respiratory burst activity significantly enhanced in the fed diet polysaccharide extract in Asian seabass (Lates calcarifer) by oral administration and the highest activity reached in 0.5% fed diet on 15th day.
Abstract: Immunostimulatory Effects of Polysaccharide Compound from Seaweed Kappaphycus alvarezii on Asian seabass (Lates calcarifer) and it’s Resistance against Vibrio parahaemolyticus
Kappaphycus alvarezii is a red seaweed rich in polysaccharides. In the present study an attempt was made to isolate polysaccharide from K. alvarezii and also tested for immunostimulatory effects on Asian seabass (Lates calcarifer) using Vibrio parahaemolyticus as a test pathogen. Two sets of experiments were designed as mixed with fed diets and intraperitoneal (IP) injection of the crude extracts. Every five days of interval, the non specific immune responses were analysed by the parameters like WBCs count, Lysozyme activity and NBT assay. After 15 days of treatment, the animals were challenged against V. parahaemolytcius and cumulative survival rates were recorded. The total white blood cells were decreased in intraperitoneal injection of polysaccharides extract after 5th day. But in fed diet cells count were significantly increased from 1st to 15th day. Fish fed diet with polysaccharide extract improved the lysozyme level than IP injection, which reduced simultaneously over the period compared with control. In the present study, the respiratory burst activity significantly enhanced in the fed diet polysaccharide extract in Asian seabass (Lates calcarifer) by oral administration and the highest activity reached in 0.5% fed diet on 15th day. After challenge with V. parahaemolyticus, all treated groups showed a reduced mortality compared to the control group. The best survival rate was observed in the group polysaccharide extract treated with 0.5% by oral administration. Among the other groups, fish treated by intraperitoneal injection had a lower survival rate than the fish treated by oral administration. However, the differences between the two sets of experiment (oral administration or intraperitoneal injection) were only 10%. UV, FT-IR, 1H and 13C NMR spectra were carried out to characterize the polysaccharide extract. The UV spectrum of the crude extract compound was showed a major peak at 282 nm. In FT-IR spectrum, major peak was observed at 1000-1100 cm-1 supports the presence of ring vibrations C-O, C-O-C (polysaccharides region) and minor peak of 1647.93 cm-1, which supports amide group. And based on the 1H and 13C NMR spectra, the presence of carbonyl carbons in the purified compound was confirmed. Findings of the present study evidenced the excellent immunostimulatory activity of polysaccharide from the seaweed Kappaphycus alvarezii. Further complete purification and characterization of the active polysaccharide and its field evaluation is needed to bring this seaweed polysaccharide as a promising candidate for the development of good immunostimulatory agent in the field of aquaculture.
TL;DR: Results demonstrate that K. alvarezii can be used as a health food and has strong anti-diabetic effects in vivo; thus, it may have beneficial properties in the prevention of diabetes and could be useful in the development of anti-Diabetic drugs.
Abstract: The intake of food and control of blood glucose levels are very important in diabetic patients. α-Glucosidase inhibitors are a cost-effective means to prevent the progression of diabetes. To find a natural inhibitor from seaweed with anti-hyperglycemic effects, methanolic extract of a red seaweed, Kappaphycus alvarezii (Doty) Doty ex P. Silva, which contains complex mixtures of various types of bioactive compounds which have a hypoglycaemic effect was evaluated in alloxan-induced diabetic rats by using two different doses (200 and 400 mg kg−1 body weight). Blood glucose, glycosylated haemoglobin, haemoglobin, serum lipids of total cholesterol, triglyceride, high-density lipoprotein cholesterol (HDL-C), phospholipids, low density lipoprotein (LDL) and plasma insulin were examined in control and seaweed extract-treated experimental rats. The aqueous extract was orally administered for 28 days. The results showed that the aqueous extract of K. alvarezii significantly (p < 0.05) reduced blood glucose level and restored glycosylated haemoglobin and plasma insulin. These results demonstrate that K. alvarezii can be used as a health food and has strong anti-diabetic effects in vivo; thus, it may have beneficial properties in the prevention of diabetes and could be useful in the development of anti-diabetic drugs.