Showing papers on "Kappaphycus alvarezii published in 2020"

Antioxidant and antibacterial activity of red seaweed Kappaphycus alvarezii against pathogenic bacteria

Abstract: Seaweeds can produce variety of bioactive components for the benefits of humans. Malaysia is one of the countries to produce red seaweeds, which are popular secondary metabolites. Kappaphycus species, largest tropical red algae exhibit the high growth rate. It was reported that its biomass can grow double in just 15 to 30 days. Therefore, this investigation emphasized on two extraction methods such as hot water and ethanolic Soxhlet extraction to extract the bioactive compounds from Kappaphycus alvarezii. Both of theseextractions were screened to produce antimicrobial and antioxidants compounds. Total phenolic content and ferric reducing assays were employed to quantify antioxidant properties. Whereas, the disc diffusion assays were used to study antibacterial activity. The results reported the highest phenolic content for ethanolic extract (20.25 ± 0.03 mg gallic acid equivalents per gram of extract). On the other hand, the value of phenolic content was slightly decreased 19.1 ± 0.81 mg gallic acid equivalents per gram of extract for the hot water extract. It was also found that both the extracts were potentially capable of balancing reactive oxygen species. Disc diffusion assay results indicated that the extract of red alga K. alvarezi were more efficient against B. cereus. Among the fatty acids determined levoglucosenone and 4-Pyridinemethanol were present in high percentages in hot water extract whereas Hexamethyl- cyclotrisiloxane followed by 1, 2, 5- Thiadiazole-3-carboxamide, 4-[(2-chloroethyl) amino]-N-(2-hydroxyethyl) were present in ethanolic extract of K. alvarezi. The present study concluded that, hot water extracts of K. alvarezii can be used for large scale production of bioactive compounds utilizing an easily available potential seaweed. Future research of red seaweed will be highly important for pharmaceutical and medicinal field as well as a homogenizer in milk products, toothpaste and jellies in other industrial applications.

Science behind biostimulant action of seaweed extract on growth and crop yield: insights into transcriptional changes in roots of maize treated with Kappaphycus alvarezii seaweed extract under soil moisture stressed conditions

Abstract: Seaweed extracts have been reported to be effective crop biostimulants having low carbon foot print. However, the mechanism of their action on crops has remained elusive due to dearth of studies. Kappaphycus alvarezii seaweed extract (K-sap) has been found to increase the yield of several crops as well as impart drought tolerance. Here, an attempt was made to get a global view of the transcriptome response of maize roots when subjected to soil drench application of K-sap under normally irrigated and drought conditions. mRNA were sequenced using high-throughput RNA sequencing employing Illumina platform and transcriptome mapping was carried out. K-sap applied plants under drought, when compared to its control, recorded several differentially expressed genes involved in RNA-, protein-, cell wall–, signaling-, transport-, stress-, development-, cell-, secondary metabolism–, hormone metabolism–, DNA-, lipid metabolism–, major and minor CHO metabolism–, redox-, metal handling–, amino acid metabolism–, nucleotide metabolism–, TCA-, and N metabolism–related pathways. Up-regulation was observed in the genes coding towards enhancement of root growth, gibberellic acid and auxin signaling, seed development, nitrogen metabolism, transport, and antioxidant activity like glutathione S-transferase and peroxidases. On the other hand, down-regulation of starch and sucrose degradation–related transcripts was apparent. These related well to our morphological observations on improved root growth, grain yield, and higher nutrient content of the roots under drought stress owing to application of K-sap. The study gives a comprehensive insight of several biological processes being modulated and opens up avenues for further targeted mechanistic studies.

Kappaphycus alvarezii macroalgae: An unexplored and valuable biomass for green biorefinery conversion

Abstract: Background Kappaphycus alvarezii is the 5th world's most cultivated macroalgae, since it is an essential source of carrageenan, widely used in food industry. However, K. alvarezii is an unexplored biomass for green biorefinery conversion, since its composition includes valuable proteins, lipids, phenolic compounds, among others. Although there are reviews on K. Alvarezii cultivation and pharmacological properties, no information is available regarding extraction techniques applied to this algae biomass. Therefore, this review covers the lack of information on biorefinery concept applied to K. alvarezii and suggest sequential extractions to recover carrageenan and high-added value molecules by using non-conventional methods. Scope and approach This critical review presents the most recent data on K. alvarezii, including its scientific trends, production and potential. It also deals with non-traditional methods for sequential extractions applied to K. alvarezii. The search for available data was extended to the group of red algae to consider the concept of biorefinery. Key findings and conclusions K. alvarezii biomass can be used to obtain chlorophyll, β-carotene, essential amino acids (aspartic acid, glutamic acid and phenylalanine) and phytohormones (indole acetic acid, zeatin, kinetin and gibberellic acid). Therefore, we provide several sustainable insights to sequentially recovery carrageenan and other bioactive compounds from K. alvarezii.

Formulation and characterization of folate receptor-targeted PEGylated liposome encapsulating bioactive compounds from Kappaphycus alvarezii for cancer therapy.

Abstract: This study aimed to formulate and characterize the folate receptor-targeted PEGylated liposome encapsulating bioactive compounds from Kappaphycus alvarezii to enhance the anticancer activity. Twenty valued bioactive compounds (3-hydroxy benzoicacid, gallicacid, chlorogenicacid, cinnamicacid, artemiseole, hydrazine carbothioamide, etc.,) are confirmed from methanol extract of K. alvarezii using analytical techniques like HPLC and GC–MS. The delivery of bioactive compounds of K. alvarezii via naturally overexpressed folate receptor (FR) to FR-positive breast cancer cells was studied. FR targeted PEGylated liposome was constructed by modified thin-film hydration technique using FA-PEG-DSPE/cholesterol/DSPC (5:40:55) and bioactive compounds of K. alvarezii was encapsulated. Their morphology, size, shape, physiological stability and drug release kinetics were studied. The study reports of K. alvarezii extract-encapsulated PEGylated liposome showed spherical shaped particles with amorphous in nature. The mean diameter of K. alvarezii extract–encapsulated PEGylated and FA-conjugated PEGylated liposomes was found to be 110 ± 6 nm and 140 ± 5 nm, respectively. Based on the stability studies, it could be confirmed that FA-conjugated PEGylated liposome was highly stable in various physiological buffer medium. FA-conjugated PEGylated liposome can steadily release the bioactive compounds of K. alvarezii extract in acidic medium (pH 5.4). MTT assay demonstrated the concentration-dependent cytotoxicity against MCF-7 cells after 24 h with IC50 of 81 µg/mL. Also, PEGylated liposome enhanced the delivery of K. alvarezii extract in MCF-7 cells. After treatment, typical apoptotic morphology of condensed nuclei and distorted membrane bodies was picturized. Additionally, PEGylated liposome targets the mitochondria of MCF-7 cells and significantly increased the level of ROS and contributes to the damage of mitochondrial transmembrane potential. Hence, PEGylated liposome could positively deliver the bioactive compounds of K. alvarezii extract into FR-positive breast cancer cells (MCF-7) and exhibit great potential in anticancer therapy.

Microwave-assisted depolymerization of carrageenans from Kappaphycus alvarezii and Eucheuma spinosum: Controlled and green production of oligosaccharides from the algae biomass

Abstract: Algae biomass is nowadays considered as a unique reservoir of a huge variety of different molecules, such as lipids, carbohydrates, proteins and secondary metabolites, awaiting development in various fields. In particular, the valorization of the algae polysaccharide content is still in its infancy and intense research activity is starting to appear. Oligosaccharides with defined molecular weight and structures are extremely interesting for different applications such as plant biostimulation or biopesticide. Oligosaccharide are often prepared in medium to large scale upon chemical-based hydrolysis reactions from the extracted polysaccharides in harsh conditions (temperature and pH), leading to the loss of the fragile groups such as the sulfate functions in carrageenans. In the present work, microwave-based hydrolysis, as a green chemistry method, is optimized to produce bioactive oligosaccharides from carrageenans. Microwave hydrolysis process is first optimized on a commercially available carrageenan and further applied on carrageenans extracted from two algae, namely Kappaphycus alvarezii or Eucheuma spinosum that are produced in large quantities in the world and have a high content of carrageenans. We also develop a complete set of characterization methods, i.e. size exclusion chromatography, reducing sugar and residual sulfate determination and mass spectrometry, to perform the follow-up of the hydrolysis reaction. We here demonstrate that fast (5 min) and controlled hydrolysis of carrageenans can be achieved in pure water under microwave activation, while preserving the nature of the active sulfate groups (>95%).

Large-scale versus family-sized system production: economic feasibility of cultivating Kappaphycus alvarezii along the southeastern coast of Brazil

Abstract: The economic viability of cultivating the seaweed Kappaphycus alvarezii, also known by the commercial name “cottonii,” on the southeastern coast of Brazil was evaluated in large-scale production systems with 13 polyvinyl chloride (PVC) rafts containing 11.44 km of tubular and family-size nets with 4 rafts and 3.52 km of nets. Deployment and operating costs and profitability ratios were estimated for three tonnes per raft production scenarios: (A) 4.0 (pessimistic), (B) 4.5 (normal conditions), and (C) 5.0 (optimistic). A sensitivity analysis simulated the loss of one crop among the five proposed growing cycles, as well as the variation in the number of rafts and selling prices for both systems. At a selling price of US$ 120.00 t−1, the 13-raft, four-crop annual large-scale production system was impractical in all proposed productivity scenarios. In the family-size production system, at a selling price of US$ 120.00 t−1, 4 rafts were not economically viable. Only the three scenarios that reached 11 rafts were viable, displaying, respectively, Internal Rates of Return (IRR) of 38.17%, 70.73% and 87.81%, a Payback Period (PP) of 31, 17 and 14 months with a Break-even Point (BP) at 78.41 tons of fresh algae. It is concluded that the activity is only economically viable on a small scale, carried out in a family-sized production system, starting with 11 rafts or 9.68 km of nets, compatible with an area of 2 ha established by the low impact aquaculture legislation in the region.

Effect of drying techniques on color and bioactive potential of two commercial edible Indonesian seaweed cultivars

Abstract: Seaweeds (Kappaphycus alvarezii and Sargassum duplicatum) are potentially rich sources of bioactive compounds and functional constituents that are used in food applications. Sun, oven, vacuum, and freeze-drying techniques are commonly used seaweed drying techniques and could be classified as cheap (sun and oven) and expensive (vacuum and freeze) drying techniques based on ovens’ market price. Therefore, the study was designed to investigate the effect of cheap (sun and oven) and expensive (vacuum and freeze) drying techniques based on color and antioxidant potential of K. alvarezii and S. duplicatum using phenolic and antioxidant assays. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were employed to discriminate the drying techniques by instrumental color analysis. The results revealed that oven-dried seaweed extracts exhibited higher levels of phenolic (0.30 to 0.36 mg GAE g−1) and antioxidant potential (3.59 to 79.68%). PCA and HCA discriminated the drying techniques into two well-defined groups/clusters I (oven, vacuum, and freeze-drying) and II (sun drying) and revealed higher ΔE values of sun-dried seaweed samples, which was interpreted as color was preserved using drying techniques of cluster I. Overall, oven, vacuum, and freeze-drying techniques reported similarities in color characteristics and could be an alternate drying technique to preserve the color of seaweed cultivars. Therefore, oven drying technique is recommended due to low cost (compared with vacuum and freeze-drying) and an affordable alternative to sun drying, the preferred technique in fishing communities of low-and-middle-income countries, for the development of seaweed-enriched functional foods.

Impact of elevated temperature on the physiological and biochemical responses of Kappaphycus alvarezii (Rhodophyta)

Abstract: The eucheumatoids Kappaphycus and Eucheuma are cultivated in tropical or subtropical regions for the production of carrageenan, a hydrocolloid widely used in the food and cosmetic industries. Kappaphycus alvarezii is a highly valued economic crop in the Coral Triangle, with the Philippines, Indonesia and Malaysia ranked among the largest producers. In the absence of measures to mitigate climate change, extreme events including heatwaves, typhoons, severe El Nino and La Nina, are expected to increase in frequency and magnitude. This inadvertently brings adverse effects to the seaweed cultivation industry, especially in the tropics. Temperatures are rapidly reaching the upper limit of biologically tolerable levels and an increase in reports of ice-ice and pest outbreaks is attributable to these shifts of environmental parameters. Nevertheless, few reports on the response of eucheumatoids to a changing environment, in particular global warming, are available. Understanding the responses and possible mechanisms for acclimation to warming is crucial for a sustainable seaweed cultivation industry. Here, the physiological and biochemical responses of K. alvarezii to acute warming indicated that the strain used in the current study is unlikely to survive sudden increases in temperature above 36°C. As temperature increased, the growth rates, photosynthetic performance, phycocolloid quality (carrageenan yield, gel strength and gel viscosity) and pigment content (chlorophyll-a, carotenoid and phycobiliproteins) were reduced while the production of reactive oxygen species increased indicating the occurrence of stress in the seaweeds. This study provides a basis for future work on long term acclimation to elevated temperature and mesocosm-based multivariate studies to identify heat-tolerant strains for sustainable cultivation.

Antioxidant properties of different strains of Kappaphycus alvarezii (Rhodophyta) farmed on the Brazilian coast

Abstract: is one of the most farmed algae globally. It is used almost exclusively for the carrageenan industry, although there is increasing interest in its biotechnological application as a natural product ...

Optimizing the application of selected biostimulants to enhance the growth of Eucheumatopsis isiformis , a carrageenophyte with commercial value, as grown in land-based nursery systems

Abstract: Eucheumatopsis isiformis Nunez-Resendiz, Dreckmann & Senties is a red alga with great economic potential due to its iota-carrageenan content that could serve as a substitute for traditional carrageenan sources (Freile-Pelegrin and Robledo, J Appl Phycol 20:537–541, 2008) such as the red alga Kappaphycus alvarezii (Loureiro et al., New Phytol 206:489–492, 2015), if it can be reliably and sustainably cultivated in open water. Due to prevailing and changing climatic conditions, it is necessary to retain germplasm and to cultivate this alga in tank systems. To develop the necessary, large volumes of seed stock required for stocking open water cultivation farms, three brown seaweed-derived biostimulants were tested. One of these was manufactured from the kelp Ecklonia maxima, the other two were manufactured from the intertidal fucoid Ascophyllum nodosum. Apical segments of E. isiformis were treated either by dipping or by continuous exposure to the biostimulants, at different concentrations. Growth was assessed every seven days by measuring the maximum length of each segment, number of lateral shoots produced by each shoot, fresh weight, and the maximum diameter. The constant exposure treatment produced a greater number of shoots per propagule with no significant effects driven by any of the biostimulants. Increasing or decreasing the concentration of the biostimulants to improve the performance of the dipping protocol was not effective, as compared with a constant exposure protocol. This study supports the increasing number of research articles related to the positive benefits of using macroalgal-derived extracts as biostimulants to support seaweed cultivation.

Isolation of phycoerythrin from Kappaphycus alvarezii : a potential natural colourant in ice cream

Abstract: Phycoerythrin (PE) is a natural protein pigment found in the red alga Kappaphycus alvarezii with potential application as a natural colourant in food and cosmetics. Therefore, this study aims to extract PE by ion-exchange chromatography and then encapsulate it with kappa-carrageenan (PE-Kc) and guar-gum (PE-Gg) to measure the stability and functionality in ice cream. Results showed that PE exhibited three distinct band subunits at α-20 kDa, β-21 kDa, and γ-30 kDa in SDS-PAGE with purity index (A563/A280) of 2.32 and is a dark pink colour. The encapsulation efficiency (EE) and of PE-Kc was 82.56% PE load 56.78%, and PE-Gg EE and PE load were 79.47% and 51.24%, respectively. Hygroscopicity index of PE-Kc and PE-Gg was between 86.94 and 90.14%, and the particle size ranged from 10 to 80 μm. Ice cream with added microencapsulated PE showed better rheology, and the intensity of pink colour increases during 90 days of storage. PE value-added ice cream showed better scavenging action against DPPH and FRAP for PE 30% and 47%, PE-Kc 20%. and 45% and PE-Gg 18% and 56%. Therefore, this study showed the techno-economic-viability of promising pigment from K. alvarezii and their potential food application.

Extraction of phycoerythrin from Kappaphycus alvarezii seaweed using ultrasonication

Abstract: Kappaphycus alvarezii is type of red seaweed that widely cultivated in Indonesia. K. alvarezii contains phycobiliproteins mainly phycoerythrin which is commonly used as natural dyes in food and cosmetics, fluorescent, and analytical reagents. Phycoerythrin is generally extracted from red seaweed using buffer phosphate with freeze thawing process. The purpose of this study was to determine the effect of extraction time using ultrasonic waves on the characteristics of phycoerythrin. The maximum absorbance was formed at a wavelength of 499, 534, and 564 nm. Ultrasonic extraction treatment for 30 min and precipitation 60% ammonium sulfate were the best treatments, which had a pigment concentration of 1.9102 mg/mL, purity index 0.8311, and protein concentration of 0.5206 mg/mL. The antioxidant activity possessed by the phycoerythrin pigment is categorized as strong to very strong.

Use of Algae Biomass Obtained by Single-Step Mild Acid Hydrolysis in Hydrogen Production by the β-Glucosidase-Producing Clostridium beijerinckii Br21

Abstract: Macroalgae biomass is a potential feedstock for fermentative H2 production: it has high carbohydrate concentration and is lignin-free. Here, we optimize a mild acid treatment of Kappaphycus alvarezii biomass by an experimental design 24. The optimal acid treatment conditions were 90 °C, HCl concentration of 55.9 mmol/L, 0.375 g of algae mass, and 8 h of treatment. Under these conditions, the hydrolysate presented mono-, but also di- and oligosaccharides. We used this hydrolysate as substrate for fermentative hydrogen (H2) production by the Clostridium beijerinckii Br21 grown in two different conditions: (1) in medium containing galactose and no β-glucosidase activity; (2) in medium with cellobiose to stimulate β-glucosidase activity, which was 0.33U/mL. The fermentative assay conducted in the presence of the C. beijerinckii Br21 with β-glucosidase activity provided higher H2 concentration and yield as compared to the assay accomplished in the presence of the inoculum with no β-glucosidase activity—171.76 ± 2.10 and 140.95 ± 10.92 mL of H2/L, and 70.3 ± 0.9 and 62.7 ± 4.9 mL of H2/g of dry algae, respectively. Therefore, a fermentative β-glucosidase-producing organism such as C. beijerinckii Br21 can potentially complete biomass saccharification for later renewable H2 production.

Bioethanol a by-product of agar and carrageenan production industry from the tropical red seaweeds, Gracilaria manilaensis and Kappaphycus alvarezii

Abstract: Two red seaweeds, Gracilaria manilaensis and K. alvarezii are cultivated in Malaysia for producing agar and carrageenan respectively. The residues of these seaweeds after removing agar and carrageenan by dilute acid treatment were subjected to enzymatic hydrolysis using cellulase (Cellic CTec 2). In the optimization of enzymatic hydrolysis, highest glucose concentration was achieved in the sample with liquid: residue ratio of 7.5:1 and enzyme loading of 10 % w/w residue. The resulted glucose was converted to bioethanol using Saccharomyces cerevisiae where bioethanol yields from G. manilaensis and K. alvarezii were 56.26 ± 1.10 g/L and 51.10 ± 1.21 g/L respectively, which, corresponded to 91 % and 95 % of the theoretical yield. Result of this study indicates that residues of these seaweeds can be efficiently converted to bioethanol and besides environmental benefits, additional profit can be achieved in the phycocolloid industry.

Genetic diversity and similarity between green and brown morphotypes of Kappaphycus alvarezii using RAPD

Abstract: The taxonomy and identification of carrageenophyte red marine algae is confused due to lack of adequate characteristics. There are also difficulties when analyzing the species, relationship between color morphotype and site of origin. Meanwhile, the use of molecular tool has been promising in identifying the similarity and genetic gap between the varieties from different location. In fact, it is useful in seaweed selection to obtain superior heredity. Genetic resources diversity provides opportunity for breeders to obtain new strains or improved varieties with more desirable characteristics. Therefore, this study aimed to compare the similarities between the green and brown morphotypes of Kappaphycus alvarezii that inhabit different sites in Indonesia. The samples were obtained from Pinrang, Lombok, and Madura and 5 primer genomes of PCR were used for DNA isolation. This was achieved by incorporating the modified phenol-chloroform method of random amplified polymorphic DNA (RAPD). The data were processed in the RAPD instance package version 1.04 supported by UPGMA (unweighted pair group method of arithmetic). These are in one package with sequential, agglomerative, hierarchical, and nested clustering (SHAN), and used to obtain data grouping based on their genetic gap. Also, analysis of the genetic relationship of K. alvarezii originating from different locations shows high gap and variation. Therefore, it was concluded that seaweeds based on their cultivation origin have higher genetic gap than those based on color. For the purpose of breeding, selection should be based on the location rather than color. Furthermore, this study showed that RAPD is effective in identifying variety differences.

Microbiome identification from ice ice disease infected Kappaphycus alvarezii using 16S rRNA gene sequence analysis and in silico docking studies against carrageenan degrading bacteria

Abstract: The seaweeds are taxonomically diverse group of marine plants found in intertidal and sub-tidal regions all over the world. Like other plants seaweeds are also affected by microbial pathogens it reduces the quality and market value of seaweeds. Kappaphycus alvarezii is a main source for carrageenan it gets affected by microbiome in unfavorable conditions which leads to the formation of white thalli disease namely called as Ice-ice disease, where the seaweed tissue become white and hard. In this study we have isolated eight different bacterial species from ice -ice diseased seaweed and identified using molecular analysis and established these species has key role to cause the disease by producing kappa carragenase enzyme which hydrolysis kappa carrageenan. Molecular docking has been extensively used to discover new targets for existing and natural bacterial compounds or enzymes. Molecular docking was employed as an effective approach to locate the potential binding site of macromolecular targets, encouraging interaction with GLN102,ARG151,TYR161,GLU163,ASP168,TRP194,ARG196,ARG260. The results suggest that molecular docking is an effective approach to locate and identify the target bacterial enzyme which has carragenan degrading activity. The present study evidently demonstrates the degrading of kappa-carragenan by kappa-carragenase enzyme from particular bacterial strain namely P.carragenovara.

Comparison of Nutritional Composition in Red and Green Strains of Kappaphycus Alvarezii Cultivated in Gorontalo Province, Indonesia

Abstract: Kappaphycus alvarezii is the most widely grown seaweed known by the commercial name “cottoni .” Several types or strains of K. alvarezii are grown in Indonesia, and each has a different appearance. There were red K. alvarezii , and green K. alvarezii collected from cultivation sites in Gorontalo Province, Sulawesi, Indonesia. The objective of this study was to compare the nutritional compositions of the red and green strain of K. alvarezii. The chemical composition analysis reveals that both strains contain ash, fat, crude fiber, protein, carbohydrate, vitamin C, and minerals; Ca (Calcium), Na (Sodium), and Fe (iron). While the red strain shows a higher ash content (4.62%), fat content (0.05%), protein (1.94%), carbohydrate (5.24%), vitamin C (3.42 mg.100 g−1 ), Na (467.65 mg.100 g− ), and Fe (30.10 mg.100 g− ), the green one has higher content of crude fiber (0.64%) and Na (9,307.17 mg.100 g− ). Based on the result, the red K. alvarezii contains higher ash, fat, protein, carbohydrate, vitamin C, Ca, and Fe, while the green K. alvarezii is higher in water content, crude fiber, and Na. These two strains have no significant differences in nutrient composition and mineral content.

Compositional and structural evaluation of Kappaphycus alvarezii rejects and solid food waste blends for bio ethanol production

Abstract: The focus of this study is to investigate the possibility of Kappaphycus alvarezii rejects (KR) and readily available solid food waste (SFW) for bioethanol production. The samples were prepared for...

Ectopic Expression of a Transmembrane Protein KaCyt b6 from a Red Seaweed Kappaphycus alvarezii in Transgenic Tobacco Augmented the Photosynthesis and Growth.

Abstract: Cytochrome b6f complex is a thylakoid membrane-localized protein and catalyses the transfer of electrons from plastoquinol to plastocyanin in photosynthetic electron transport chain. In the present...

Strain selection for growth enhancement of wild and cultivated eucheumatoid seaweed species in Indonesia

Abstract: A poor seed quality is one of the main constraints to provide a fast growth for seaweed production. It is hoped that seaweed strain selection may lead to production of a high quality seed, resulting in an enhanced growth rate of cultivated seaweeds. The study aimed to obtain a fast growing seaweed strain through proper selection. Three types of base strains were selected: A wild type of Eucheuma denticulatum from Nusa Tenggara Timur (NTT), and two types of cultivated seaweed of Kappaphycus alvarezii from Takalar and Gorontalo, respectively. The collected seaweeds were grown in Laikang Bay using the long line method. The strain selection was based on the daily growth rate (DGR) parameter. The seaweeds were cultivated for 30 days to produce seed, and selected seed material was used for the next cycle for three cycles. The results show that the selected seaweed strains had a higher DGR compared with nonselected (internal control) seed from each of the original forms. DGR of the selected and control seed of the Takalar, Gorontalo, and NTT strains were 6.67% day-1 and 4.91% day-1; 4.23% day-1 and 2.00% day-1; and 2.23% day-1 and 1.20% day-1, respectively. The selection technique increased the DGR up to 1.68% day-1 for three cultivation cycles, while carrageenan content was up to 4.7% higher than the internal control. In conclusion, the best strain for cultivation in Laikang Bay was that of selected from Takalar.

PRODUCTION OF THE Kappaphycus alvarezii EXTRACT AS A LEAF BIOFERTILIZER: TECHNICAL AND ECONOMIC ANALYSIS FOR THE NORTH COAST OF SÃO PAULO-BRAZIL

Abstract: The extract of the Kappaphycus alvarezii seaweed is used as a leaf biofertilizer and several studies had proven its efficiency in several crops. This study aimed to analyze the economic viability of fresh seaweed production and the chemically characterized seaweed extract cultivated as a technical-economic alternative for coastal communities. Yields of the solid and liquid fractions were quantified, the extract was characterized in its chemical composition of macronutrients and micronutrients and it was classified according to the criteria of the Brazilian legislation of agricultural fertilizers. For the study of economic feasibility, different sales price scenarios were considered and compared with the commercialization of fresh seaweed. The average yield obtained from the processing of the Brazilian adapted strains of the K. alvarezii for the liquid fraction or fresh seaweed extract was 0.71 ± 0.0080 L kg-1 and the moisture solid production was 295 ± 0.0126 g kg-1. The production of fresh seaweed was unfeasible and for the handmade extract was economically viable for the scenario with the sale price of US$ 2.77 with a net present value of US$ 35,300.13 and an internal rate of return (IRR) of 38.99% over ten year.

Water quality study in several seaweeds culture sites in the post-earthquake-tsunami Palu Central, Sulawesi Province

Abstract: On September 28, 2018 the Palu City and its surroundings experienced an earthquake of M 7.4 and Tsunami. This incident had a major impact on the community, especially seaweed farmers. The study aims to determine the effect of water quality on the production of seaweeds (Kappaphycus alvarezii and Spinosum sp) post-earthquake-tsunami in Central Sulawesi. This study are located Parigi Moutong and Donggala Regency. The research variables were observed include quality of the seawater and seaweeds production before-after the earthquake-tsunami Palu. Suitability of seaweed culture identification using Principal Component Analysis (PCA). The results showed that the location most suitable seaweeds culture is at a spacing of 300-500 meters from the river mouth while the water quality such as temperature, salinity, brightness, depth, dissolved oxygen, pH, surface current, pH, phosphate, nitrate, TDS and TSS, still within acceptable limits for the growth and production of seaweeds. Gracilaria sp. can no longer becultivated after an earthquake disaster due to the pond water quality not supporting its growth. Spinosum sp is more cultivated than Kappaphycus alvarezii in Parimo and Donggala, with a decrease in seaweeds production 50-60% after the earthquake-Tsunami Palu.

Monitoring environmental risk of the exotic species Kappaphycus alvarezii (Rhodophyta), after two decades of introduction in southeastern Brazil

Abstract: Abstract Kappaphycus alvarezii was introduced for mariculture purposes on the coast of São Paulo, southeast of Brazil, in 1995, and since then an experimental pilot cultivation has been maintained. Since it is an exotic species, the dispersion of thallus fragments, presence of reproductive structures and recruitment from spores were monitored bimonthly from November 2016 to January 2018. Fragment dispersion was analyzed on nine selected monitoring sites around the cultivation raft through visual observation and photographic records. To verify the presence of reproductive structures 40 individuals were collected randomly from the cultivation raft and analyzed under a light microscope and stereomicroscope. Reproductive structure recruitment was also evaluated using artificial substrata. The results showed that even 25 years after the introduction of K. alvarezii on the coast of São Paulo, the invasive behavior of this exotic species had not been recorded. There was no evidence of vegetative dispersion and/or establishment in the Ubatuba Bay. Reproductive structures were also not found during the monitoring period. However, we highlight the importance of permanent and systematic environmental monitoring to prevent any impact and to ensure a sustainable aquaculture. These results will contribute to the development of the cultivation of the non-native K. alvarezii in Brazil and to improving public policies of coastal management.

Genetic Diversity Analysis of Cultivated Kappaphycus in Indonesian Seaweed Farms using COI Gene

Abstract: Indonesia is a major player in the aquaculture of red algae, especially carrageenan producing ‘eucheumatoids’ such as Kappaphycus and Eucheuma. However, many current trade names do not reflect the evolutionary species and updated taxonomy, this is especially the case for eucheumatoid seaweeds that are highly variable in morphology and pigmentation. Genetic variation is also not known for the cultivated eucheumatoids in Indonesia. Therefore, this study aimed to determine the species and the level of genetic variation within species of cultivated eucheumatoids from various farms across Indonesia, spanning 150-1500 km, using the DNA barcoding method. Samples of seaweed were randomly collected at 14 farmed locations between April 2017 and May 2018. For this study the 5-prime end (~ 600 bp) of the mitochondrial-encoded cytochrome oxidase subunit one (COI) was amplified and sequenced. Morphological examination showed that the samples were quite variable in branching pattern and color. All samples collected from farms with floating line cultivation were identified based on COI sequences as Kappaphycus alvarezii and showed no variation in the COI gene. One farm sample with bottom-line cultivation was identified as K. striatus. The low genetic variation is in contrast to the phenotypic variation of samples, indicating that variation and phenotypic responses to environments is still found in samples with implications for growth rates and carrageenan yield and quality. Information about the genetic variation in stocks is important base knowledge for maintaining, expanding and continuing seaweed aquaculture.

High-quality de novo genome assembly of Kappaphycus alvarezii based on both PacBio and HiSeq sequencing

Abstract: The red algae Kappaphycus alvarezii is the most important aquaculture species in Kappaphycus, widely distributed in tropical waters, and it has become the main crop of carrageenan production at present. The mechanisms of adaptation for high temperature, high salinity environments and carbohydrate metabolism may provide an important inspiration for marine algae study. Scientific background knowledge such as genomic data will be also essential to improve disease resistance and production traits of K. alvarezii. 43.28 Gb short paired-end reads and 18.52 Gb single-molecule long reads of K. alvarezii were generated by Illumina HiSeq platform and Pacbio RSII platform respectively. The de novo genome assembly was performed using Falcon_unzip and Canu software, and then improved with Pilon. The final assembled genome (336 Mb) consists of 888 scaffolds with a contig N50 of 849 Kb. Further annotation analyses predicted 21,422 protein-coding genes, with 61.28% functionally annotated. Here we report the draft genome and annotations of K. alvarezii, which are valuable resources for future genomic and genetic studies in Kappaphycus and other algae.