Auswahl der wissenschaftlichen Literatur zum Thema „Marine Biomass (Seaweed)“

Seaweeds are among the most important biomass feedstocks for the production of third-generation biofuels. They are also efficient in carbon sequestration during growth and produce a variety of high-value chemicals. Given these characteristics together with the relatively high carbohydrate content, seaweeds have been discussed as an ideal means for CO2 capture and biofuel production. Though third-generation biofuels have emerged as some of the best alternatives to fossil fuels, there is currently no large-scale production or mainstream use of such liquid fuels due to the many technical challenges and high production costs. The present study describes the concept of coastal marine biorefineries as the most cost-effective and sustainable approach for biofuel production from seaweeds, as well as atmospheric carbon capture and storage (CCS). The suggested refinery system makes use of marine resources, namely seawater, seaweed, and marine microorganisms. Firstly, extensive screening of the current literature was performed to determine which technologies would enable the emergence of such a novel biorefinery system and its merits over conventional refineries. Secondly, the study investigates various scenarios assessing the potential of seaweeds as a means of carbon sequestration. We demonstrate that the removal of 100 Gigatons of excess CO2 using seaweed farms can be achieved in around 4 months to less than 12 years depending on the area under cultivation and the seaweed species. The total bioethanol that could be generated from the harvested biomass is around 8 trillion litres. In addition, high-value chemicals (HVC) that could potentially be recovered from the process represent a considerable opportunity with multi-billion-dollar commercial value. Overall, coastal marine biorefineries have strong potential for a sustainable green economy and represent a rapid approach to climate change mitigation.

Over the past decades, ocean temperatures have been steadily increasing and are projected to continue to do so, stressing many temperate marine organisms. Changing temperatures do not affect ecosystems in isolation, but interact with many other factors in shaping ecological communities. We investigated the changes over 2 decades in subtidal temperate seaweed communities over a wave exposure gradient in Western Australia, a global warming hotspot. We found higher diversity in the seaweed community and a higher proportion of biomass of species with a warm affinity (expressed as the tropicalization index: TI) over time. There was no decline in biomass of the dominant habitat-forming kelp Ecklonia radiata on low wave exposure reefs, while it was patchier and comprised a lower proportion of the total seaweed biomass on the medium and high wave exposure reefs. Furthermore, the presence of E. radiata was disproportionally associated with low abundances of seaweeds with warm affinity. The increasing patchiness of E. radiata likely provided a competitive release for other seaweeds, and the increase in abundance of Scytothalia dorycarpa likely provided a compensatory effect which resulted in a lower than expected TI. We found no indication of an ameliorating effect by wave exposure, and conclude that the patch dynamics driven by wave exposure are more likely exacerbated by increasing ocean temperatures on subtidal temperate reefs. If this continues, the reduction in E. radiata and increase in warm affiliated seaweeds will result in a more diverse seaweed community, but one with a lower standing biomass.

Fossil fuel depletion, climate change, and increased global energy demands are the driving forces to find alternative sources of energy. Marine-based biorefinery has been recently discussed as a promising route to mitigate the environmental challenges, enhance the energy recovery, and provide a potential source for value-added products. Anaerobic digestion is a promising technology that can convert the organic compounds of marine ecosystems into biogas. To date, a comprehensive review incorporating integrated biogas potential and effective approaches to enhance seaweed digestibility for biogas production from marine resources has not been reported. Thus, the present review aims to explore and comprehensively present seaweed and other marine resources for potential biogas production. The basics and challenges of biogas production from seaweed are elucidated. The impact of biochemical composition on biogas and the microbial communities involved in anaerobic digestion of seaweed are discussed. Utilization of different techniques such as pretreatment, co-digestion, and sequential extraction of seaweed biomass to enhance the biogas yield and to mitigate the effect of inhibitors are presented. Specifically, this article evaluates the co-digestion of seaweed with other biomass feedstocks or liquid biowastes. Integration of marine microalgae cultivation on anaerobic digestate for value-added compound production, biogas upgrading, and bioenergy recovery provides a promising approach towards a zero-waste marine-based system.

Biochar made from seaweed biomass of marine farms established for water pollutant remediation may be a promising amendment for soil remediation in the same coastal territory. The study aimed to assess the soil Cu-immobilizing, pH neutralizing, and nutrient improvement capabilities of a seaweed biochar when incorporated into degraded soil of the same coastal territory (Puchuncaví District, central Chile). Experimental design considered five treatments; degraded soil of Puchuncaví valley (C-), C- amended with either local seaweed biochar (B), vermicompost (V), or its mixture (BV), and a background soil (C+). Experimental soils were placed in pots and kept in a greenhouse (4 weeks). Lolium perenne was then sown and cultivated until week 11. Treatments amended with biochar (B and BV) significantly increased soil pH, available nitrogen and decreased Cu2+ ions. These treatments reached very high EC values but had no negative effect on plant yield. Regarding plant growth, V and BV significantly increased biomass, but V resulted in higher yield because of its higher nutritional status. It was concluded that seaweed biochar, made from local seaweed biomass of a coastal marine water pollutant remediation farm, may be an effective soil amendment for degraded soils of the same coastal territory, although its combination with an organic amendment should be considered.

Macroalgae are considered as the 3rd generation of biofuels and a future feedstock for biorefinery. This research aims to provide simple and dependable analytical techniques for measuring the thermal characteristics of dried seaweed. The main objective was to investigate the thermal characteristics of four seaweed species utilizing a thermogravimetric analyzer. The seaweeds Gracilaria fisheri, Caulerpa lentillifera, Ceramium rubrum, and Eucheuma cottonii were collected from the Pahang state of Peninsular Malaysia. The calorific value of the samples was revealed by using a calorimeter. Ceramium rubrum showed the highest calorific value, while Gracilaria fisheri had the most negligible calorific value among the selected samples. The thermogravimetric analysis (TGA) data revealed that the most significant weight loss for this biomass occurred between 160 and 300° for the selected species. Gracilaria fisheri has shown the highest decomposition with the minor residue at 30.26%, whereas Caulerpa lentillifera has a slow weight loss rate in the mentioned range. SEM analysis has been used to perform the morphology of samples, which shows differences in the concentration of epiphytic diatoms with different structural shapes. Based on the results, macroalgae is a promising sustainable biomass feedstock for biofuel application.

We performed a cost-benefit analysis for bioethanol production using biomass of Ulva rigida, a marine macroalga (seaweed), co-cultured with fish in an intensive offshore aquaculture unit. This is the first report for such analysis that takes into consideration offshore seaweed cultivation and uses a recently developed, novel and simplified ethanol production technology that is devoid of costly pre-treatments imposed to the seaweed biomass. By simultaneously producing ethanol with valuable Dried Distillers Grains with Solubles (DDGS) by-products such as animal feed, the economic viability of this system is plausible over a production range of 77–240 dry tons of seaweed per day. As such, applying the model to suggested future scenarios for the Israeli Mediterranean shorelines, which limits aquaculture to ca. 600 ha, results in unprofitability. Further, sensitivity analyses place profitability as mainly dependent on DDGS prices and on the daily growth rate (biomass yield) of the macroalga. These two are key factors to achieve profitability at the 600-ha scenario.

A survey was conducted to know the present status of naturally occurring seaweed flora and their utilization in Bangladesh by interviews of scientific officers of MFTS (Marine Fisheries and Technology Station, Bangladesh Fisheries Research Institute, Cox’s Bazar), NGO officials associated with seaweed research project, local seaweed food products manufacturer, seaweed collectors and Mog or Rakhyine tribal community of Cox’s Bazar and St. Martin Island. Lack of knowledge on availability, distribution, seasonal variation, utilization status is causing impediment on utilization (e.g. seaweeds as human food, hydrocolloids, animal feed, fertilizer, cosmetic products, etc.) of available seaweeds naturally occurring in Bangladesh. Seaweeds are available along the whole Bangladeshi coast, mostly in St. Martin Island, Cox’s Bazar and Sundarbans Mangrove forest. Total 193seaweed species including 19 commercially important species, belonging to 94 genera are found. Approximately, 5,000 metric ton of seaweed biomass is available. Due to seasonal variation in water quality parameters, generally seaweeds are available from October to April, but highest abundance occurs from January to March. Seaweed salad and sauce has been utilizing by Mog people as food. About 400 seaweed collectors at St. Martin Island annually harvested 6-9 metric tons of wet seaweeds (Hypnea spp.) for smuggling to Myanmar. Different value added food, functional food and personal care products have prepared by Govt. institution, NGO and in private sector. Considering the economic importance and potentials of seaweeds, for effective and environmentally sustainable utilization, special concern is required by both government and private organizations.Res. Agric., Livest. Fish.3(1): 203-216, April 2016

AbstractDue to its large, exclusive economic zone, India has considerable potential for implementing large-scale cultivation of macroalgae. However, such cultivation requires the availability of, and access to, sites where technical, legal, governmental, and environmental factors are favorable. This review discusses the challenges that have held back the development of seaweed cultivation in India. The review is based on a literature survey and informal discussions with industry-related personnel. It cites the strong need for clear and definitive policies related to access to and use of coastal waters to enable the Indian seaweed industry to reach its full potential. The main challenges that the expansion of macroalgal cultivation in India face are related to legal and regulatory aspects that can be resolved by focusing the policy issues on providing planning tools toward success. In addition, there is a strong need for an adequate bioeconomy that clearly defines the need for marine macroalgal biomass for food, chemicals, and biofuels. Furthermore, the Indian government needs to allocate sufficient funds for accelerating seaweed R&D in areas of seaweed cultivation, harvesting, processing technologies, and their implementation in the local industry.

This study explored the development of hierarchical graphitic carbon structures (HGCs) from harmful inedible seaweed waste harvested in the summer. Elevated sea temperatures during the summer increase the cellulose content of seaweeds, making them unsuitable for consumption. By utilizing seaweed biomass, this study addresses critical marine environmental issues and provides a sustainable solution for promising electrode materials for energy storage devices. The fabrication process involved impregnating seaweed with Ni ions, followed by annealing to create a highly crystalline carbon structure. Subsequent etching produced numerous nano-sized pores and a large surface area (806 m2/g), significantly enhancing the number of electrically active sites. The resulting HGCs exhibited a high capacitance and maintained their capacity even after 10,000 cycles in fast-current systems. This innovative approach not only mitigates the environmental burden of seaweed waste but also offers a sustainable method for converting it into efficient energy storage materials.

Abstract The extensive coastline and numerous islands of Malaysia provide various habitats suitable for the growth of a diversity of the marine macroalgae (seaweeds). Since the last checklist of the Malaysian seaweeds was published in 2006, there has been an increase of 17 families, 32 genera, and 75 species. Seven new species were described. The present tally stands at 459 taxa in 72 families; with 35 species in 12 families of Cyanophyta; 113 species in 16 families of Chlorophyta; 95 species in 8 families of Ochrophyta; and 216 species in 36 families of Rhodophyta. Only three species, Kappaphycus alvarezii, Eucheuma denticulatum and Gracilaria manilaensis, are being cultivated commercially. A small seaweed industry centered in Sabah, produces semi-refined carrageenan, which is mainly exported. Some of the biomass is brought over to Peninsular Malaysia, where seaweed products like desserts, health drinks, soaps and air-fresheners, are manufactured and sold. In 2016, Malaysia produced 205,989 tonnes wet weight seaweeds valued at US$24.83 million. The seaweed industry, can be enhanced by increasing the number of farms and farmers, strengthening local seaweed cooperatives and including them in decision-making, as well as by technological advances in the form of new and improved strains, more efficient seed supply and products.

This thesis evaluates the performance of marine algal-based biosorbents in treating trace metal bearing aqueous solutions. Native seaweed varieties (Ascophyllum nodosum, Lessonia flavicans, Durvillea potatorum and Laminaria hyperborea) were selected on the basis of their varying algin composition as well as their characteristic mannuronic/guluronic acid content. Dealginated seaweed residues, i.e. waste materials arising during algin extraction from brown marine algae were also evaluated as potential metal biosorbent materials. The biosorbents showed significant metal sorption capacity for copper, cadmium, nickel and zinc from synthetic single metal and multi-metal bearing aqueous solutions. The equilibrium biosorption process may be described using a surface complex formation model. Copper biosorption involved chelation-type surface reactions as well as ion exchange whereas nickel and zinc biosorption may be described by simple ion exchange and electrostatic interactions between metal ions and the negatively charged algal surface. Evidence of stoichiometric release of protons upon metal biosorption has been found. Metal biosorption was found to be dependent upon transport limitations due to intraparticle diffusion. Surface functional groups within algal biosorbents that are responsible for metal-ion binding were identified in an attempt to understand the mechanisms of metal biosorption. Physical and chemical characterization techniques such as potentiometric titrations and esterification were used for surface acidity measurements, nitrogen sorption porosimetry for surface area and pore size distribution analysis and FT-IR spectroscopy to identify carboxyl groups attached to structural polysaccharides in algae. Performance of native and dealginate algal fixed-bed mini-columns provided optimum operating conditions for dynamic exchange between metal ions in solution and the algal biomass. Selected biosorbents were successfully employed to treat real industrial metal-plating rinse waters. The most efficient eluants for regeneration of metal-laden biosorbent columns were also identified.

by Lau Tsz Chun.
Thesis (M.Phil.)--Chinese University of Hong Kong, 2000.
Includes bibliographical references (leaves 134-143).
Abstracts in English and Chinese.
Acknowledgements --- p.i
Abstract --- p.ii
Contents --- p.vi
List of Figures --- p.xi
List of Tables --- p.xv
Chapter 1. --- Introduction --- p.1
Chapter 1.1 --- Reviews --- p.1
Chapter 1.1.1 --- Heavy metals in the environment --- p.1
Chapter 1.1.2 --- Heavy metal pollution in Hong Kong --- p.3
Chapter 1.1.3 --- Electroplating industries in Hong Kong --- p.7
Chapter 1.1.4 --- "Chemistry, biochemistry and toxicity of selected metal ions: copper, nickel and zinc" --- p.8
Chapter a. --- Copper --- p.10
Chapter b. --- Nickel --- p.11
Chapter c. --- Zinc --- p.12
Chapter 1.1.5 --- Conventional physico-chemical methods of metal ions removal from industrial effluent --- p.13
Chapter a. --- Ion exchange --- p.14
Chapter b. --- Precipitation --- p.14
Chapter 1.1.6 --- Alternative for metal ions removal from industrial effluent: biosorption --- p.15
Chapter a. --- Definition of biosorption --- p.15
Chapter b. --- Mechanisms involved in biosorption of metal ions --- p.17
Chapter c. --- Criteria for a good metal sorption process and advantages of biosorption for removal of heavy metal ions --- p.19
Chapter d. --- Selection of potential biosorbent for metal ions removal --- p.20
Chapter 1.1.7 --- Procedures of biosorption --- p.23
Chapter a. --- Basic study --- p.23
Chapter b. --- Pilot-scale study --- p.25
Chapter c. --- Examples of commercial biosorbent --- p.27
Chapter 1.1.8 --- Seaweed as a potential biosorbent for heavy metal ions --- p.27
Chapter 1.2 --- Objectives of study --- p.30
Chapter 2. --- Materials and Methods --- p.33
Chapter 2.1 --- Collection of seaweed samples --- p.33
Chapter 2.2 --- Processing of seaweed biomass --- p.33
Chapter 2.3 --- Chemicals --- p.33
Chapter 2.4 --- Characterization of seaweed biomass --- p.39
Chapter 2.4.1 --- Moisture content of seaweed biomass --- p.39
Chapter 2.4.2 --- Metal ions content of seaweed biomass --- p.39
Chapter 2.5 --- Characterization of metal ions biosorption by seaweed --- p.39
Chapter 2.5.1 --- Effect of biomass weight and selection of biomass --- p.39
Chapter 2.5.2 --- Effect of pH --- p.40
Chapter 2.5.3 --- Effect of retention time --- p.41
Chapter 2.5.4 --- Effect of metal ions concentration --- p.41
Chapter 2.5.5 --- Effect of mix-cations and mix-anions on the removal capacity of selected metal ions by Ulva lactuca --- p.43
Chapter 2.5.6 --- Recovery of adsorbed metal ions from Ulva lactuca (I): screening for suitable desorbing agents --- p.44
Chapter 2.5.7 --- Recovery of adsorbed metal ions from Ulva lactuca (II): multiple adsorption-desorption cycles of selected metal ions --- p.45
Chapter 2.5.8 --- Removal and recovery of selected metal ions from electroplating effluent by Ulva lactuca --- p.45
Chapter 2.6 --- Statistical analysis of data --- p.46
Chapter 3. --- Results --- p.47
Chapter 3.1 --- Effect of biomass weight and selection of biomass --- p.47
Chapter 3.1.1 --- Effect of biomass weight --- p.47
Chapter 3.1.2 --- Selection of biomass --- p.58
Chapter 3.2 --- Effect of pH --- p.58
Chapter 3.2.1 --- Cu2+ --- p.58
Chapter 3.2.2 --- Ni2+ --- p.61
Chapter 3.2.3 --- Zn2+ --- p.61
Chapter 3.2.4 --- Determination of optimal condition for biosorption of Cu2+ ，Ni2+ and Zn2+ by Ulva lactuca --- p.67
Chapter 3.3 --- Effect of retention time --- p.67
Chapter 3.4 --- Effect of metal ions concentration --- p.73
Chapter 3.4.1 --- Relationship of removal capacity with initial concentration of metal ions --- p.73
Chapter 3.4.2 --- Langmuir adsorption isotherm --- p.73
Chapter 3.4.3 --- Freundlich adsorption isotherm --- p.77
Chapter 3.5 --- Effect of mix-cations and mix-anions on the removal capacity of selected metal ions by Ulva lactuca --- p.81
Chapter 3.5.1 --- Effect of mix-cations --- p.81
Chapter 3.5.2 --- Effect of mix-anions --- p.85
Chapter 3.6 --- Recovery of adsorbed metal ions from Ulva lactuca (I): screening of suitable desorbing agents --- p.91
Chapter 3.6.1 --- Cu2+ --- p.91
Chapter 3.6.2 --- Ni2+ --- p.91
Chapter 3.6.3 --- Zn2+ --- p.91
Chapter 3.7 --- Recovery of adsorbed metal ions from Ulva lactuca (II): multiple adsorption-desorption cycles of selected metal ions --- p.94
Chapter 3.8 --- Removal and recovery of selected metal ions from electroplating effluent by Ulva lactuca --- p.97
Chapter 4. --- Discussion --- p.106
Chapter 4.1 --- Effect of biomass weight and selection of biomass --- p.106
Chapter 4.1.1 --- Effect of biomass weight --- p.106
Chapter 4.1.2 --- Selection of biomass --- p.107
Chapter 4.2 --- Effect of pH --- p.109
Chapter 4.3 --- Effect of retention time --- p.112
Chapter 4.4 --- Effect of metal ions concentration --- p.114
Chapter 4.4.1 --- Relationship of removal capacity with initial concentration of metal ions --- p.114
Chapter 4.4.2 --- Langmuir adsorption isotherm --- p.114
Chapter 4.4.3 --- Freundlich adsorption isotherm --- p.115
Chapter 4.4.4 --- Insights from isotherm study --- p.117
Chapter 4.5 --- Effect of mix-cations and mix-anions on the removal capacity of selected metal ions by Ulva lactuca --- p.118
Chapter 4.5.1 --- Effect of mix-cations --- p.118
Chapter 4.5.2 --- Effect of mix-anions --- p.120
Chapter 4.6 --- Recovery of adsorbed metal ions from Ulva lactuca (I): screening of suitable desorbing agents --- p.122
Chapter 4.7 --- Recovery of adsorbed metal ions from Ulva lactuca (II): multiple adsorption-desorption cycles of selected metal ions --- p.124
Chapter 4.8 --- Removal and recovery of selected metal ions from electroplating effluent by Ulva lactuca --- p.126
Chapter 5. --- Conclusion --- p.131
Chapter 6. --- Summary --- p.134
Chapter 7. --- References --- p.134
Chapter 8. --- Appendixes --- p.144

This thesis examines the contribution of a non-indigenous red alga, Mazzaella japonica, to wrack subsidies in Baynes Sound, British Columbia, and the effects of its removal by a commercial beach-cast harvest. Field and laboratory work was conducted to determine: 1) How large wrack inputs are in terms of biomass and spatial extent within the harvest region, and what proportion of this is comprised of M. japonica; 2) how wrack characteristics influence associated macrofauna communities; 3) if there is any detectable effect of beach-cast harvesting on either the wrack characteristics or macrofauna communities; and 4) if M. japonica provides a food source for native invertebrate consumers within the subtidal and supralittoral zones. Field surveys conducted from November 2014 through March 2015 found that wrack biomass within the harvest region could reach as much as 853 kg (±173 SD) per meter of shoreline, and cover up to 35 m2 (± 3 SD) of beach surface within this area. The macrophyte composition of the wrack was dominated by M. japonica, which accounted for 90% of the identifiable macrophyte biomass on average. Wrack in the later stages of decomposition hosted the most speciose and diverse assemblages of macrofauna, though community composition also differed among collection sites and with depth of the wrack. Though we were limited in our ability to disentangle the effects of beach-cast harvesting due to a concentration of effort at one site, we failed to detect any large influence on wrack biomass or macrofauna communities. Harvesting does, however, appear to be associated with a greater area of wrack cover and decreased mean depth. Stable isotope mixing models estimated that M. japonica contributed no more than 22% and 17% on average to the diets of supralittoral and subtidal consumers respectively, despite its overwhelming dominance in both environments. These results suggest that the non-indigenous red alga may experience a reprieve from herbivory within the subtidal environment. A lack of consumption within the supralittoral zone could influence nutrient cycling on recipient beaches and increase propagule pressure in the surrounding regions. Results from these studies are intended to help inform the management of M. japonica and its commercial harvesting. Combined, they indicate that this non-indigenous seaweed does not provide a substantial subsidy in the form of food provision for resident invertebrates. Furthermore, the commercial removal of M. japonica is small compared to the total biomass available, and had no detectable effect on the wrack-associated macrofauna communities examined.
Graduate
2017-08-19
jjulin.holden@gmail.com

Seaweeds are predominantly macroscopic, multicellular, and photosynthetic marine algae that grow primarily in the ocean’s rocky littoral zone. About 154 seaweed species are found in our coastal area, of which 34 belong to green (Chlorophyta), 38 brown (Phaeophyta), and 82 red (Rhodophyta). Among them, 26 species are considered economically important based on their availability, abundance, and use. Seaweeds are mainly available in St. Martin Island, Shaporir dip, Inani, Bakkhali, Kutubdia, Patowartek, Pecherdwip, Teknaf, Shaplapur, and Moheshkhali in Cox’s Bazar region of Bangladesh. They are generally found on our Cox’s Bazar coast from October to April, but the highest abundance occurs from January to March. However, in the case of mangrove forests, seaweeds are available throughout the year. Additionally, seven species are considered commercially cultivable species. Their culture techniques were developed in the long-line and net methods at different Cox’s Bazar region sites. St. Martin Island had the highest biomass yield production of seaweed due to its favorable water quality parameters. Several value-added seaweed products were developed from dried seaweed powder. Industries based on seaweed can potentially contribute to the socioeconomic upliftment of the coastal inhabitants in Cox’s Bazar.

This chapter provides an overview of the environmental impacts of the supply chain for preserved seaweed. The supply chain includes the hatchery, marine infrastructure, deployment of juveniles and monitoring during cultivation (grow-out of seaweed), harvest, transport back to shore and preservation of the biomass. The chapter starts with a short overview of the life cycle assessment (LCA) methodology, and how it can be used to quantify the environmental impacts of seaweed supply chains. After a discussion of the overall environmental impacts of the preserved seaweed supply chain, the chapter focuses on specific life cycle stages: spore preparation and seeding of juvenile seaweed onto string in the hatchery, seaweed cultivation, harvesting preservation and storage of harvested seaweed. The chapter ends with a summary and discussion of future trends in the subject.

Cancer is one of the most serious and common human diseases, causing millions of deaths per year worldwide. Currently, the discovery of noble therapeutic agents with a natural origin for cancer treatment is a major challenge. In this context, marine algae with wide species and phytochemical diversity will offer great scope for the discovery of new drugs. Algae with marine origin, including microalgae and macroalgae (seaweeds), constitute more than 90% of oceanic biomass. Marine algae are rich sources of pigments, lipids, carotenoids, omega-3 fatty acids, polysaccharides, vitamins and other fine chemicals. The biomaterials obtained from marine algae are important ingredients in many products, including cosmetics and drugs for treating cancer and other diseases. The in vitro and in vivo evaluations of biomolecules derived from marine algae have shown a vast range of pharmacological properties such as antioxidant, immunostimulatory and antitumor activities to control cancer. In spite of the rich source of various bioactive molecules, the marine algal flora largely remains unexplored for the discovery of active molecules against cancer to date. Hence, this review consolidates the available information on marine algae-derived anticancer molecules to provide baseline information for promoting anticancer research based on biomaterials derived from marine algae.

In the marine rocky intertidal ecosystem, macroalgae (seaweeds) serve ecosystem engineers that create, modify, or maintain the physical habitat for their own and other species. Intriguingly, most marine macroalgal species evolved with microbial colonization and biofilm formation on their surface. The macroalgae (basibiont) and associated epiphytic microbiota (epibiont) act as a functional unit known as a “macroalgal holobiont,” characterized by its complex chemical interactions. In this non-trophic association, the epiphytic microbial biofilm forms a protective layer essential in host defense against foulers, consumers, or pathogens. In addition, antimicrobial activity is widespread among these epiphytic microbes. However, due to their thinness and often negligible biomass, the chemo-ecological impact of this epiphytic microbiome is severely underestimated. This chapter aims to review the antimicrobial potential of the “macroalgal epiphytic microbiome” and introduce the application of “meta-omics” approaches for further exhaustive exploitations of this unique microbiome for future drug discovery.

Macroalgae cultivation in the ocean stands as a promising source of feedstock for biofuels and chemicals. It is particularly attractive because of the efficiency of these marine plants in converting sunlight into biomass and because this type of farming can be done without the risk of displacing land and freshwater from their essential role in feeding the human population. However, there are challenges to achieving this potential due to the limitations of present farming methods. In order to compete economically with land-based biomass production, the bioeconomics of seaweed farming must improve and the areas where it can be practiced must be expanded. Present methods of growing seaweeds are confined to narrow strips along the coasts that are both protected and sufficiently shallow. In order to meaningfully exploit the US Exclusive Economic Zone (EEZ), engineered systems must be developed for high-energy locations in deep water and at an unprecedented scale. This paper will present an innovative design for the farming seaweed in the open ocean and will describe a series of tests conducted at Ohmsett - The National Oil Spill Response Research & Renewable Energy Test Facility - in Leonardo, NJ. The facility was used for these tests because the capabilities matched well testing needs and because the facility uses seawater. Actual fronds of kelp were needed for testing in order to correlate their hydrodynamic characteristics with the scaled materials in 1/20th-scale testing of the structure that was the prime focus of the tests. The results on the resistance testing of single and multiple fronds of kelp will be reported as well as those for the model materials. The results of the tests on various structural models both in currents and in currents and waves will be presented. These tests allowed the measurement of system drag and loads internal to the structure. Accelerations were also measured to determine motions and to predict inertial loading. These tests have allowed us to more confidently design prototype systems that have the potential to revolutionize the domestic seaweed-farming sector.

The FAO has projected a doubling in world demand for seafood during the 21 ed from aquaculture of marine fish and shrimps fed primarily on fishmeal-based aquafeeds. However, current practices of high intensity monoculture of shrimp in coastal ponds and fish in offshore pens have been strongly criticized as being ecologically and socially unsustainable. This view derives from un- checked eutrophication of coastal marine ecosystems from fish farm effluents, and the destruction of coastal estuarine ecosystems by shrimp farm constructions, plus aquaculture’s reliance on wild-caught small fish - which are excellent food for humans, but instead are rendered into fishmeal and fish oil for formulating aquafeeds. Fishmeal-sparing and waste- reduction aquafeeds can only delay the time when fed aquaculture product are priced out of affordability for most consumers. Additionally, replacement of fishmeal protein and fish oil by terrestrial plant sources such as soybean meal and oil directly raises food costs for human communities in developing nations. New formulations incorporating sustainably-produced marine algal proteins and oils are growing in acceptance as viable and practical alternatives. This BARD collaborative research project investigated a sustainable water-sparing spray/drip culture method for producing high-protein marine macrophyte meals for incorporation into marine shrimp and fish diets. The spray culture work was conducted at laboratory-scale in the USA (UCSD-SIO) using selected Gracilariaand Ulvastrains isolated and supplied by UCONN, and outdoors at pilot-scale in Israel (IOLR-NCM) using local strains of Ulvasp., and nitrogen/phosphorus-enriched fish farm effluent to fertilize the spray cultures and produce seaweed biomass and meals containing up to 27% raw protein (dry weight content). Auburn University (USA) in consultation with TAMUS (USA) used the IOLR meals to formulate diets and conduct marine shrimp feeding trials, which resulted in mixed outcomes, indicating further work was needed to chemically identify and remove anti-nutritional elements present in the IOLR-produced seaweed meals.

The War in the Pacific National Historical Park (WAPA), a protected area managed by the National Park Service (NPS), was established "to commemorate the bravery and sacrifice of those participating in the campaigns of the Pacific Theater of World War II and to conserve and interpret outstanding natural, scenic, and historic values on the island of Guam." Coral reef systems present in the park represent a vital element of Guam?s cultural, traditional, and economical heritage, and as such, are precious and in need of conservation. To facilitate the management of these resources, NPS determined that a scleractinian (stony coral) species survey was necessary to establish a baseline for existing coral communities and other important factors for conservation. EnviroScience, Inc. performed a survey of stony coral species, coral habitat, and current evidence of stressors at WAPA?s H?gat and Asan Units in 2022. This report summarizes these findings from a management perspective and compares its findings to previous survey data from 1977 and 1999 (Eldridge et al. 1977; Amesbury et al. 1999). WAPA is located on the tropical island of Guam, located on the west-central coast of the island, and encompasses 2,037 acres. Underwater resources are a significant component of the park, as 1,002 acres consists of water acres. The park is comprised of seven units, of which two of these, the H?gat and Asan Beach Units, include all the oceanic water acres for the park. The H?gat Beach Unit (local spelling, formerly known as ?Agat?) is located at the south-west portion of the park and consists of 38 land acres and 557 water acres (NPS 2003). The Asan Beach Unit consists of 109 acres of land and 445 water acres (NPS 2003). A current baseline for existing coral communities and other important factors for conservation necessitates the need for up-to-date data on the location, presence, relative abundance, and present health of corals. Park managers need this updated data to determine where and how to best focus conservation priorities and identify restoration opportunities. Management actions in park reef areas informed by this inventory included identifying locations where there were: high rates of sedimentation; high coral biomass; rare or threatened species, with a priority given to species endemic to Guam and listed as ?threatened? under the U.S. Endangered Species Act (ESA; Acropora globiceps, A. retusa, A. speciosa, and Seriatopora aculeata); coral persistence and decline, disease and/or nuisance species, including the crown-of-thorns starfish (Acanthaster cf. solaris, ?COTS?) and the sponge Terpios hoshinota; and bleached areas. All work carried out was in accordance with the NPS statement of work (SOW) requirements, which involved a quantitative inventory using both new and pre-existing transects. The resulting transects totaled 61 (including the four from the 1999 study), each measuring 50 meters in length and distributed across depths of up to 50 feet. Divers took photo-quadrat samples covering an area of approximately 9 m?, encompassing 50 photo-quadrats of dimensions 0.50 m x 0.36 m (n=50). The collective area surveyed across all 61 transects amounted to ~549 m?. Additionally, a qualitative search was conducted to enhance documentation of coral species that have limited distribution and might not be captured by transects, along with identifying harmful species and stressors. Timed roving diver coral diversity surveys were carried out at a total of 20 sites occurring within the waters of WAPA, including eight sites at the H?gat unit and 12 sites at the Asan unit. The findings from this report reveal significant disparities in benthic cover compositions between H?gat and Asan units. The H?gat unit exhibits high abundances of turf algae and unconsolidated sediment while the Asan beach unit presents a different scenario, with hard coral as the dominant benthic cover, followed closely by crustose coralline algae (CCA). The Asan unit is also more difficult to access from shore or boat relative to H?gat which provides that unit some protection from human influences. The Asan beach unit's prevalence of hard coral, CCA, and colonizable substrate suggests a more favorable environment for reef growth and the potential benefits of maintaining robust coral cover in the area. These distinct differences in benthic communities highlight the contrasting ecological dynamics and habitats of the two study areas. Across both H?gat and Asan beach unit transects, a total of 56 hard coral species were recorded from 27 genera, with 44 species recorded from the H?gat unit and 48 species recorded from the Asan unit. Of the four historical transects surveyed in the Asan unit from 1999, three experienced declines in percent coral cover (17.38-78.72%), while the fourth had an increase (10.98%). During the timed roving diver coral diversity surveys, a total of 245 hard coral species, including 241 scleractinian coral species representing 49 genera and 4 non-scleractinian coral species representing 4 genera were recorded. Uncertainties related to coral identification, unresolved boundaries between morphospecies, differences in taxonomists' perspectives, and the rapidly evolving state of coral taxonomy have significant implications for species determinations during coral diversity surveys. While the recent surveys have provided valuable insights into coral diversity in WAPA waters, ongoing taxonomic research and collaboration among experts will be essential to obtain a more comprehensive and accurate understanding of coral biodiversity in the region. Of the several ESA coral species that were searched for among the H?gat and Asan beach units, Acropora retusa was the only coral species found among quantitative transects (n=2) and A. globiceps was observed during coral diversity surveys. Acropora speciosa, which was dominant in the upper seaward slopes in 1977, is now conspicuously absent from all the surveys conducted in 2022 (Eldredge et al., 1977). The disappearance and reduction of these once-dominant species underscores the urgency of implementing conservation measures to safeguard the delicate balance of Guam's coral reefs and preserve the diversity and ecological integrity of these invaluable marine ecosystems. Other formerly common or locally abundant species were infrequently encountered during the diversity surveys, including Acropora monticulosa, A. sp. ?obtusicaulis?, A. palmerae, Stylophora sp. ?mordax?, Montipora sp. ?pagoensis?, and Millepora dichotoma. Significant bleaching-associated mortality was recorded for these species, most of which are restricted to reef front/margin zones exposed to moderate-to-high levels of wave energy. Sedimentation was present in both H?gat and the Asan units, though it was more commonly encountered in H?gat transects. While significant portions of the reef area within the WAPA H?gat unit are in poor condition due to a variety of stressors, some areas still hosted notable coral communities, which should be a potential focus for park management to prevent further degradation. There is a need for more effective management of point source pollution concerns, particularly when subpar wastewater treatment or runoff from areas with potential pollution or sediment-laden water is flowing from nearby terrestrial environments. Future monitoring efforts should aim to establish a framework that facilitates a deeper understanding of potential point source pollution incidents. This would empower park managers to collaborate with adjacent communities, both within and outside of park boundaries, to mitigate the localized impacts of pollution (McCutcheon and McKenna, 2021). COTS were encountered during transect surveys as well as in coral diversity surveys. including along the upper reef front/reef margin at site Agat-CS-2. The frequency of these observations, particularly in the WAPA H?gat unit and where stress-susceptible corals are already uncommonly encountered, raise concern about the ability of the populations of these coral species to recover following acute disturbance events, and calls in to question the ability of some of these species to persist in WAPA waters, and in Guam?s waters more broadly. More frequent crown-of-thorns control efforts, even if only a handful of sea stars are removed during a single effort, may be required to prevent further loss to vulnerable species. There were several documented incidents of Terpios hoshinota covering large sections of branching coral in the reef flat along transects, but it is still unclear how detrimental this sponge is to the overall reef system. There is a concern that elevated levels of organic matter and nutrients in the water, such as those resulting from sewage discharge or stormwater runoff, could lead to increased Terpios populations (De Voogd et al. 2013). Consequently, it is important to track populations in known areas of sedimentation and poor water quality. The presence of unique species at single survey sites within the study areas underscores the ecological importance of certain locations. Some species are known to occur in other locations in Guam, while a few may be limited to specific sites within WAPA waters. These differences are likely influenced by environmental and biological factors such as poor water quality, severe heat stress events, chronic predation by crown-of-thorns sea stars, disease, and reduced herbivore populations. These factors collectively shape the condition of the benthic community, leading to variations in species distribution and abundance across the study sites. Documenting coral stress and identifying potentially harmful species allows for proactive management strategies to prevent the establishment of nuisance or detrimental species while populations are still manageable. Updated data on the location, presence, relative abundance, and health of corals is essential for park managers to prioritize conservation efforts and identify restoration opportunities effectively. Observations from this report raise concerns about the health and resilience of coral ecosystems in the H?gat unit and emphasize the need for knowledge of local factors that shape benthic community structure. Understanding the drivers responsible for these variations is crucial for effective conservation and management strategies to preserve the ecological balance and overall health of coral reefs in both units. Continued monitoring efforts will be critical in assessing long-term trends and changes in benthic cover and enabling adaptive management approaches to safeguard these valuable marine ecosystems in the face of ongoing environmental challenges.