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  • Considering the importance of seaweeds for the development of sustainable and innovative food products, this study aimed to characterize the impact of hydrothermal processing on iodine, sodium, potassium, selenium, and arsenic concentrations of four seaweed species (S. latissima, L. digitata, U. pinnatifida, and C. crispus) and on the associated health risks-benefits for consumers. These elements revealed a common pattern for leachable fractions of iodine, total arsenic, and selenium: L. digitata S. latissima > C. crispus > U. pinnatifida after rehydration and boiling during different periods. The behavior for sodium was: S. latissima > L. digitata > C. crispus > U. pinnatifida, and for potassium: U. pinnatifida > L. digitata > S. latissima > C. crispus. Generally, the species that attained more significant losses were S. latissima and L. digitata. A health-relevant sodium/potassium ratio below 0.7 was found for all species except for U. pinnatifida. In some species, the risk-benefit analysis revealed that high iodine and arsenic levels might promote risks for consumption, even after 20 min boiling, but 5 g of processed U. pinnatifida could contribute to adequate iodine, sodium, potassium, and selenium intakes for all population groups. Standardized processing treatments of seaweeds can open new opportunities for the sector.

    Author(s): Helena Correia, Cristina Soares, Simone Morais, Edgar Pinto, Antonio Marques, Maria Leonor Nunes, Agostinho Almeida, Cristina Delerue-Matos
  • Background Due to its short lifetime food packaging leads to a rapid accumulation of plastic in our surroundings and thereby also has a huge impact on environmental pollution. To reduce these effects and create a more sustainable approach towards food packaging biodegradable and biobased polymers have been developed and are emerging on the market. Scope and approach This review provides the current state of research regarding active packaging and the incorporation of seaweed into food packaging. Further, it summarises the resulting consequences of the seaweed incorporation on mechanical, physical, thermal, antioxidant, antimicrobial and chemical properties, as well as the release of active compounds to show the advantages of the polysaccharides as well as possible shortcomings in current research. Key findings and conclusions To improve these polymers regarding their mechanical, thermal and antimicrobial properties etc. a variety of polysaccharides such as seaweeds can be used. They not only lead to an increase in hydrophilicity and improved mechanical properties such as tensile strength and elongation at break, but also create the possibility of using it as active packaging. This can be achieved due to the naturally occurring antioxidant properties in seaweed, which can minimise lipid oxidation and thereby increase the shelf life and nutritional value of food as well as reduce free radicals which might have a carcinogenic, mutagenic or cytotoxic effect. Some seaweeds such as H. elongate have also proven to inhibit the growth of gram-positive and gram-negative bacteria, meaning that they could possibly be used as antimicrobial packaging.

    Author(s): Dietz Carina, Shubham Sharma, Amit K. Jaiswal, Swarna Jaiswal
  • This article discusses seaweeds, their uses, and their potential uses. Includes tables with values and tonnage of important maricultured seaweeds.

    Author(s): T. Chopin, M. Sawhney
  • We compared post-harvest processing of two species of Ulva (chlorophyta) using 36 washing time-by-temperature combinations. We quantified the yield of crystallized salt after evaporation of the washing water as a target product and characterized the composition of salts and processed biomass, with the additional aim of improving the composition of the processed biomass for production of fertilizer, feed or fuel. Washing of biomass of Ulva ohnoi and Ulva tepida effectively reduced its mineral content with concomitant production of crystalline salts with Na:K ratios of 1.1-2.2 and a maximum of 19% soluble fiber (ulvan). The maximum yield of salt was 29% of the biomass for U. ohnoi and 36% for U. tepida. Salts from both species have potential for human health applications and functional foods. Washing increased the energy content of the biomass from both species by 20-50% to a maximum of 18 MJ kg-1 and protein contents by 11-24% to a maximum of 27.4%. The production of seaweed salt is therefore a novel first step in a cascading biorefinery model for the utilization of macroalgal biomass which simultaneously improves the quality of the processed biomass for production of fertilizer, feed or fuel.

    Author(s): Marie Magnusson, Christina Carl, Leonardo Mata, Rocky de Nys, Nicholas A. Paul
  • The southern coast of Tamil Nadu (Mandapam to Kanyakumari) supports luxuriant growth of economic seaweeds. The entire indigenous phycocoUoid industry of the country gets the raw material from this region and during the last two decades, due to indiscriminate harvesting, there has been over-exploitation of the resource. The present paper deals with survey conducted in the first sector from Tuticorin to Tiruchendur during December 1986—March 1987. In this study 58 species of marine algae were recorded of which 7 belong to Chlorophyta, 12 to Phaeophyta and 39 to Rhodophyta besides 3 species of seagrasses namely Cymodocea seiriilata, Halophila ovalis and //. ovata within 650 sq. km area surveyed. The total standing crop of the seaweeds was estimated at 9,100 tonnes (wt.). The estimates for the dominant species are Dictyota maxima 530 t, Sargassum tenerrium 640 t, D. bartayresiana 8601, Selieria rebusta 2,0901 and Hypnea valemiae 2,4301. The seaweed potential for commercial exploitation has been briefly discussed.

    Author(s): Chennubhotla, V S Krishnamurthy, Kaliaperumal, N, Kalimuthu, S, Ramalingam, J R, Subbaramaiah, K, Rao, K Rama, Rao, P V Subba
  • The macroscopic algae comprising the three major classes Ghlorophyceae (green alga<'), Phaeophyceae (brown algae) and Rhodophyceae (red algae), found mostly in the inter-tidal zone on the rocky coasts, are commonly referred as seaweeds. Recently their use as an industrial raw material in the production of agir and algin has created a great dem nd and attempts are under way to augment the resources by aquaculttire practices. The Central Marine Fisheries Research Institute is playing a leading role in developing the techniques of seaweed culture in the Gulf of Mannar and Palls Bay. A gross picture of the seaweed resources along the coasts of mainland of India is available (Thivy, 1958; Rao, 1967. 1970).

    Author(s): Gopinathan, C P , Panigrahy, R
  • Pathogenic microbes can devastate populations of marine plants and animals. Yet, many sessile organisms such as seaweeds and sponges suffer remarkably low levels of microbial infection, despite lacking cell-based immune systems. Antimicrobial defenses of marine organisms are largely uncharacterized, although from a small number of studies it appears that chemical defenses may improve host resistance. In this study, we asked whether the common seaweed Lobophora variegata is chemically defended against potentially deleterious microorganisms. Using bioassay- guided fractionation, we isolated and characterized a 22-membered cyclic lactone, lobophorolide (1), of presumed polyketide origin, with sub-M activity against pathogenic and saprophytic marine fungi. Deterrent concentrations of 1 were found in 46 of 51 samples collected from 10 locations in the Bahamas over a 4-year period. Lobophorolide (1) is structurally unprecedented, yet parts of the molecule are related to tolytoxin, the scytophycins, and the swinholides, macrolides previously isolated from terrestrial cya- nobacteria and from marine sponges and gastropods. Until now, compounds of this structural class have not been associated with marine macrophytes. Our findings suggest that seaweeds use targeted antimicrobial chemical defense strategies and that sec- ondary metabolites important in the ecological interactions be- tween marine macroorganisms and microorganisms could be a promising source of novel bioactive compounds.

    Author(s): Julia Kubanek
  • This manual is designed for farmers, buying agents, exporters and fisheries officers who play an important role in achieving the required quality of seaweed for export. The purpose of the manual is to educate farmers to understand the importance of good-quality seaweed, the role they play and the benefits they can achieve. The manual also provides guidance for buying agents, exporters and fisheries officers in the roles they perform to improve and maintain the required quality of seaweed.

    Author(s): Gideon Tiroba
  • The use of seaweeds has a long history, as does the cultivation of a select and relatively small group of species. This review presents several aspects of seaweed production, such as an update on the volumes of seaweeds produced globally by both extraction from natural beds and cultivation. We discuss uses, production trends and economic analysis. We also focus on what is viewed as the huge potential for growing industrial-scale volumes of seaweeds to provide sufficient, sustainable biomass to be processed into a multitude of products to benefit humankind. The biorefinery approach is proposed as a sustainable strategy to achieve this goal. There are many different technologies available to produce seaweed, but optimization and more efficient developments are still required. We conclude that there are some fundamental and very significant hurdles yet to overcome in order to achieve the potential contributions that seaweed cultivation may provide the world. There are critical aspects, such as improving the value of seaweed biomass, along with a proper consideration of the ecosystem services that seaweed farming can provide, e.g. a reduction in coastal nutrient loads. Additional considerations are environmental risks associated with climate change, pathogens, epibionts and grazers, as well as the preservation of the genetic diversity of cultivated seaweeds. Importantly, we provide an outline for future needs in the anticipation that phycologists around the world will rise to the challenge, such that the potential to be derived from seaweed biomass becomes a reality.

    Author(s): Alejandro H. Buschmann, Carolina Camus, Javier Infante, Amir Neori, Álvaro Israel, María C. Hernández-González, Sandra V. Pereda, Juan Luis Gomez-Pinchetti, Alexander Golberg, Niva Tadmor-Shalev, Alan T. Critchley
  • The seaweed industry in India is mainly a cottage industry and is based only on the natural stock of agar yielding red seaweeds, such as Gelidiella acerosa and Gracilaria edulis, and algin yielding brown seaweed species such as Sargassum,and Turbinana. India produces 110-132 t of dry agar annually utiliziog about 880-1100 t of dry agarophytes and 360-540 t of algin froln 3 600-5 400 t of dry alginophytes.

    Author(s): Kaladharan, P, Kaliaperumal, N

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