Digital library

• Anaerobic Digestion is an exothermal four-step breakdown of a wide range of biomass(carbs, protein, fat) into C1/C2molecules, reversing photosynthesis (=a mechanical cow)
• Methanogenesis, the last of the four steps, requiresmcractivity only found inArchae, and releasesmethane as value product into the gas phase, lowering the thermodynamic cost of separation
• AD is rate limited byArchaeagrowth rates (doubling times) to 20d HRT
• Seaweed is largely an inconvenient, high-ash, high-salt substrate with challenging logistics andmoderate conversion performance as feed, and hence as AD substrate, while competing withabundant terrestrial biomass that is now left unused to decompose, with easier to accessibility
• Various LCA models have shown irrecoverable CI scores (+120-+150 g CO2eq/ MJ)
• Key value drivers for CNG are ecosystem services, i.e. methane and pollution avoidance or carbonsequestration, resulting in renewable fuel production (i.e. LCFS, REDD2), and not merely thecommodity revenue
• Price is a function of amount, form, location, use, time and environmental attributes
• Conversion rates of 60-80% leave biomass digestate as burden and boon

There is epidemiological evidence that dietary intake of seaweeds is associated with a lower prevalence of chronic diseases. While seaweeds are of high nutritious value, due to their high content of fiber, polyunsaturated fatty acids and minerals, they also contain an abundance of bioactive compounds. There is a growing body of scientific data that these bioactive moieties exert effects that could correct the metabolic dysregulation that is present in obesity and Type 2 diabetes (T2D). In this review we describe how the molecular mechanisms, specific to different tissues, that underly obesity and T2D are influenced by both seaweed extracts and seaweed-derived bioactive molecules. In obesity, modulation of antioxidant capacity and reduction of intracellular ROS levels within tissues, and regulation of signaling pathways involved in enhancing browning of white adipose tissue, have been highlighted as key mechanism and identified as a potential target for optimal energy metabolism. In T2D, management of post-prandial blood glucose by modulating α-glucosidase or α-amylase activities, modulation of the AMPK signaling pathway, and similarly to obesity, reduction of ROS and NO production with subsequent increased expression of antioxidant enzymes have been shown to play a key role in glucose metabolism and insulin signaling. Future studies aimed at discovering new therapeutic drugs from marine natural products should, therefore, focus on bioactive compounds from seaweed that exert antioxidant activity and regulate the expression of key signaling pathways involved in glucose homeostasis, mechanisms that are common to both obesity and T2D management. In addition, more data is required to provide evidence of clinical benefit.

Teagasc researchers are looking to seaweed for proteins with health benefits for use as functional foods. Historically, edible seaweeds were consumed by coastal communities across the world and today seaweed is a habitual diet in many countries, particularly in Asia. Indeed, whole seaweeds have been successfully added to foods in recent times, ranging from sausages and cheese to pizza bases and frozen-meat product.

At a Seaweed Workshop organized earlier this year by Maine Sea Grant and principally funded by Maine Aquaculture Innovation Center, Tollef Olsen commented that although he has been referring to seaweed as “the virtuous vegetable,” he’s wondered if instead, he should describe it as “the versatile vegetable.” Presentations given by participants at the conference revealed that both descriptions are apt.