Our planet is supposed to host 11.213 billion people by the end of the year 2100. Such demographic explosion poses serious problems for human life quality and security. Generally, the term “seaweed” is conventionally used to designate multicellular marine algae. In the last three decades, and due to the high diversity of their metabolites, seaweeds are used in medicine to treat gall stones, stomach ailments, eczema, cancer, renal disorders, scabies, psoriasis, asthma, arteriosclerosis, heart disease, lung diseases, ulcers, etc. Compounds like carotenoid, polysaccharides, fatty acids, glycoproteins, haloforms, halogenated alkanes, alkenes, alcohols, aldehydes, hydroquinones, ketones, phlorotannins, pigments, lectins, alkaloids, terpenoids, sterols and some heterocyclic and phenolic compounds are among the most important seaweed substances that receive attention from pharmaceutical companies for use in drug development, or from scientists in the field of medical research. The potential pharmaceutical, medicinal and investigatory applications of these compounds in antibiotic, antiviral, anticancer, antioxidants, anti-inflammatory, anticoagulants, and antidiabetic production are discussed in this chapter.
Digital library
-
-
Anthropogenic disturbances, including coastal habitat modification and climate change are threatening the stability of kelp beds, one of the most diverse and productive marine ecosystems. To test the effect of temperature and irradiance on the microscopic gametophyte and juvenile sporophyte stages of the rare kelp, Saccharina angustissima, from Casco Bay, Maine, USA, we carried out two sets of experiments using a temperature gradient table. The first set of experiments combined temperatures between 7-18°C with irradiance at 20, 40, and 80 μmol photons m-2 s-1. The second set combined temperatures of 3-13°C with irradiance of 10, 100, and 200 μmol photons m-2 s-1. Over two separate 4-week trials, in 2014 and again in 2015, we monitored gametogenesis, the early growth stages of the gametophytes, and early sporophyte development of this kelp. Gametophytes grew best at temperatures of 8-13°C at the lowest irradiance of 10-μmol photons m-2 s-1. Light had a significant effect on both male and female gametophyte growth only at the higher temperatures. Temperatures of 8-15°C and irradiance levels of 10-100 μmol photons m-2 s-1 were conditions for the highest sporophyte growth. Sporophyte and male gametophyte growth was reduced at both temperature extremes—the hottest and coldest temperatures tested. S. angustissima is a unique kelp species known only from a very narrow geographic region along the coast of Maine, USA. The coupling of global warming with high light intensity effects might pose stress on the early life-history stages of this kelp, although, as an intertidal species, it could also be better adapted to temperature and light extremes than its subtidal counterpart, Saccharina latissima.
-
Following first-generation and second-generation biofuels produced from food and non-food crops, respectively, algal biomass has become an important feedstock for the production of third-generation biofuels. Microalgal biomass is characterized by rapid growth and high carbon fixing efficiency when they grow. On account of potential of mass production and greenhouse gas uptake, microalgae are promising feedstocks for biofuels development. Thermochemical conversion is an effective process for biofuel production from biomass. The technology mainly includes torrefaction, liquefaction, pyrolysis, and gasification. Through these conversion technologies, solid, liquid, and gaseous biofuels are produced from microalgae for heat and power generation. The liquid bio-oils can further be upgraded for chemicals, while the synthesis gas can be synthesized into liquid fuels. This paper aims to provide a state-of-the-art review of the thermochemical conversion technologies of microalgal biomass into fuels. Detailed conversion processes and their outcome are also addressed.
-
Today’s fish - dominated seafood consumption pattern cannot be sustained, since supply has shifted from capture to culture (each currently at around 100 million tons/y). Already today, seaweeds (macroalgae) and shellfish dominate mariculture. To prevent crises, wise policies could anticipate this inevitable shift, by promoting seaweed and shellfish production and consumption. The current rate of expansion in mariculture production will inevitably rise in the long run. Eventually, the seafood share in global food supplies, primarily in 3rd world countries, will rise, with the emerging global exhaustion of arable land and freshwater reserves. The sea remains the world’s last food frontier – the only environment that is still available for expansion of food production. A sustainable expansion of seafood culture by orders of magnitude necessitates a balance, as in agriculture, between fed aquatic animals (fish, shrimp…) and extractive plants and animals (bivalves, detritivores). Extractive organisms ameliorate the environmental impacts of the fed animals’ farming, while bringing more income and jobs. Cultured seaweeds, with their biochemical composition and high protein content, can also replace much of the fishmeal in aquaculture diets and provide humanity with nutritious protein.
-
Scientists at the University of Manchester in the UK have made a breakthrough in the production of biofuels, using synthetic biology to make the next generation of bio-based jet fuels from seawater.
The researchers, who are led by Professor Nigel Scrutton, director of the Manchester Institute (MIB) and supported by US-based international maritime research agency Office of Naval Research Global (ONR), is using synthetic biology to identify a more efficient method of producing biofuel.
-
Seaweed genetic engineering is a transgenic expression system with unique features compared with those of heterotrophic prokaryotes and higher plants. This study discusses several newly sequenced seaweed nuclear genomes and the necessity that research on vector design should consider endogenous promoters, codon optimization, and gene copy number. Seaweed viruses and artificial transposons can be applied as transformation methods after acquiring a comprehensive understanding of the mechanism of viral infections in seaweeds and transposon patterns in seaweed genomes. After cultivating transgenic algal cells and tissues in a photobioreactor, a biosafety assessment of genetically modified (GM) seaweeds must be conducted before open-sea application. We propose a set of programs for the evaluation of gene flow from GM seaweeds to local/geographical environments. The effective implementation of such programs requires fundamentally systematic and interdisciplinary studies on algal physiology and genetics, marine hydrology, reproductive biology, and ecology.
-
Selaru Island community has long ago been familiar with activity of fulfilling needs through Tnyafar. Being a local wisdom, every household used Tnyafar as a livelihood strategy. Through Tnyafar, community exploited natural resources regularly to ensure the fulfillment of the needs. This research was aimed to analyze community activity that based on local wisdom and to understand the position of local wisdom in the process of fulfilling needs. Research used qualitative approach. Data collection technique involved depth interview and focussed group discussion. Informants were selected with Snowball Technique with land-owner as key informants. Other informants included Tnyafar Chief, Village Chief, and Tnyafar members either men or women. Result of research indicated that Tnyafar was a local wisdom expression in small island that takes into account the limited natural resources as the inheritance for the next generation. Also through Tnyafar, community did work activity together to ensure the fulfillment of needs. All the needs including food, cloth and shelter were fulfilled through the work output at Tnyafar.
-
In a powerful piece about global hunger, Kenneth R. Weiss shows readers the landscape in Dadaab, Kenya, where people are suffering and dying from chronic undernourishment and hunger-related conditions.
-
Michael Conathan is the Director of Ocean Policy at the Center for American Progress. This blog in Seafood News is in response to the New York Times Magazine essay contest that challenged its readers to make the argument that eating meat is ethical.
-
Physiological responses to the hypo-osmotic and temperature stresses of an invasive species, Gracilaria vermiculophylla, were compared to those of the native Atlantic species, G. tikvahiae and G. cervicornis. For the hypoosmotic and lower lethal temperature experiment, a Connecticut (CT) strain of the invasive G. vermiculophylla and a Rhode Island (RI) strain of the native G. tikvahiae were cultivated at combinations of five different salinities (S ¼ 5, 15, 20, 25 and 30) and at five different temperatures (58C, 108C, 158C, 208C and 258C) for 3 weeks. For the upper lethal temperature experiment, two strains of G. vermiculophylla from CT and Portugal, two strains of G. tikvahiae from CT and RI and one Florida strain of G. cervicornis were cultivated at temperatures ranged from 228C to 398C in 28C or 38Cincrements for 14 days. Gracilaria vermiculophylla showed a wide range of temperature (58C–348C) and salinity (5 – 30 S) tolerance; whereas, G. tikvahiae cannot withstand harsher environmental stresses, such as prolonged exposures to salinities of 20 S and temperatures of 108C or 348C. Gracilaria vermiculophylla also grew faster and had higher survival rates than G. tikvahiae or G. cervicornis. These results suggest that the high tolerance and growth capacity of G.vermiculophylla may be responsible for the successful invasion of this alga into Long Island Sound and elsewhere along the east coast of North America.
Pages
Marine Agronomy Group, CAFNRM, UH-Hilo
200 W. Kawili st., HI 96720, USA
Contact: Marine.Agronomy.Group@gmail.com
Funding for this web portal is provided by the World Wildlife Fund and the University of Hawaii-Hilo.