Digital library

To meet carbon emissions targets, more than 30 countries have committed to boosting production of renewable resources from biological materials and convert them into products such as food, animal feed and bioenergy. In a post-fossil-fuel world, an increasing proportion of chemicals, plastics, textiles, fuels and electricity will have to come from biomass, which takes up land. To maintain current consumption trends the world will also need to produce 50–70% more food by 2050, increasingly under drought conditions and on poor soils. Depending on bioenergy policies, biomass use is expected to continue to rise to 2030 and imports to Europe are expected to triple by 2020. Europe is forecast to import 80 million tons of solid biomass per year by 2020 (Bosch et al. 2015).

Producing large volumes of seaweeds for human food, animal feed and biofuels could represent a transformational change in the global food security equation andin the way we view and use the oceans. In 2012, global production of seaweeds was approximately 3 million tons dry weight, and growing by 9% per annum. Increasing the growth of seaweed farming up to 14% per year would generate 500 million tons dry weight by 2050, adding about 10% to the world’s present supply of food, generating revenues and improving environmental quality (Table 1). Assuming a conservative average productivity from the best operating modern farms of about 1,000 dry metric tons per km2 (1 kg per m2), this entire harvest could be grown in a sea area of about 500,000 square kilometers, 0.03% of the oceans’ surface area, equivalent to 4.4 percent of the US exclusive economic zone.

Plastics are carbon-based polymers and we make them mostly from petroleum. With the discovery of plastics, life became much more convenient because it is used to make a wide array of useful materials. But these plastics are so durable that it will take many centuries for these plastics to completely degrade while other plastics will last forever. Discarded plastics are also a big cause of pollution and because of that, plastics make our environment a much less attractive place (Atienza, 2009).

Getting rid of plastics is extremely difficult. Burning these plastics gives off harmful chemicals such as dioxins that could contribute to Global Warming. Recycling these plastics is also difficult because there are many different kinds of plastics and each has to be recycled by a different process. Though these plastics are considered to be one of the greatest innovations ever, they are also imposing a great havoc to the environment, the wildlife and the general public (Woodford, 2008). For this reason, this study aims to develop a biomass-based plastic from the natural polysaccharides of seaweeds.

Biomass-based plastics or bioplastics are a form of plastics derived from renewable biomass resources like vegetable oil or corn starch rather than the conventional plastics which are made from petroleum. Their advantage are innumerable and one is their capability to biodegrade naturally within a short period of time only (Sweeney, 2008). 

Seaweeds are best known for the natural polysaccharides that can be extracted from them which are widely used particularly in the fields of food technology, biotechnology, microbiology and even medicine but not yet in the plastic industry. Some of these polysaccharides are Floridean starch, agar and alginate (Montano, 2010) Since they are renewable biomass resources and are polymers made from sugars which contain carbon, they could be used to create a bioplastic. 

In this study, the natural polysaccharides from selected Philippine marine seaweeds will be utilized to develop a biodegradable and high-quality bioplastic. 

Background: Seaweed is a popular traditional food in Japan and is a rich source of bioactive metabolites. The neuroprotective properties of seaweed have attracted attention; to date, however, there has been no epidemiological evidence regarding the relationship between seaweed consumption and depression. The current cross-sectional study investigated the association between seaweed consumption and depressive symptoms during pregnancy in Japan.

Methods: Study subjects were 1745 pregnant women. Depressive symptoms were defined as present when subjects had a Center for Epidemiologic Studies Depression Scale score of 16 or higher. Dietary consumption during the preceding month was assessed using a self-administered diet history questionnaire. Adjustment was made for age; gestation; region of residence; number of children; family structure; history of depression; family history of depression; smoking; secondhand smoke exposure at home and at work; job type; household income; education; body mass index; and intake of fish and yogurt.

Results: The prevalence of depressive symptoms during pregnancy was 19.3%. After adjustment for possible dietary and non-dietary confounding factors, higher seaweed consumption was independently associated with a lower prevalence of depressive symptoms during pregnancy: the adjusted odds ratios (95% confidence intervals) for depressive symptoms during pregnancy in the first, second, third, and fourth quartiles of seaweed consumption were 1 (reference), 0.72 (0.51 − 1.004), 0.71 (0.50 − 1.01), and 0.68 (0.47 − 0.96), respectively (P for trend = 0.03).

Conclusions: The present results suggest that seaweed consumption may be inversely associated with the prevalence of depressive symptoms during pregnancy in Japanese women.

The world-wide macroalgae industry has increased exponentially over the last 50 years (Fig. 1a,b). Between 2003 and 2012, its average annual growth was 8.13% in quantity and 6.84% in monetary value (Food & Agriculture Organization of the United Nations (FAO), 2014). Over 23 million tons of macroalgae (dry weight) were produced in 2012 from aquaculture, which were worth over six billion US$ (FAO, 2014). Approximately 83% of this biomass is produced for human consumption while the remainder is used as fertilizers, animal feed additives and, increasingly, for medical and biotechnological applications (McHugh, 2003). Seaweeds have a recognized, though barely tapped, potential for biotechnology and sustainable biofuel production (Mazarrasa et al., 2014). A more immediate expansion driver is, however, the prospect that seaweed farming can improve the sustainability of fish and shellfish aquaculture in integrated cultivation initiatives. With an annual growth of nearly 10%, fish farming is the world’s most rapidly expanding food-producing sector and represents a major stake toward meeting soaring global demand for dietary proteins over the forthcoming decades (Duarte et al., 2009). Encouraged by these demands and efforts to reduce the over-exploitation of natural resources, seaweed farming has been expanding rapidly across several continents from south-eastern Asia down to South America and East Africa (Rebourset al., 2014).