Seaweed, Versatile Marine Resource for Food, Animal Feeds, Fertilizers, Medicine

By Henrylito Tacio

Davao, 26 August 2009. With a coastline of 36,289 kilometers, Philippines has marine resources that could provide food to millions of Filipinos and even livelihood to a great number of rural families.

Onse such marine resource is seaweeds. It grows abundantly in shallow reef and lagoons with less than two meters in depth during high tide.“Our seaweed production is still the biggest aquaculture producer of the country providing livelihood to more than 100,000 poor coastal families,” reports Dr. Rafael D. Guerrero III, the PCAMRD executive director.

“The average income per family is P15,000 per 60 days per one-fourth hectare.” As an industry, seaweed farming or the gathering of natural stocks is a viable venture. Currently, there are more than 150,000 hectares of seaweed farms throughout the country. Most of them are found in coastal barangays in Western Mindanao, Central and Eastern Visayas, and Southern Tagalog. These regions account for 60% of the country’s total production.

Philippines, a pioneer in seaweed farming, have cultures of Porphyra, Eucheuma, and Caulerpa in marine farms have been recorded as early as the 1960s. Through the initiative of Dr. Max Doty, a marine botanist at the University of Hawaii, and his local counterparts, the first technology for culture of Eucheuma was introduced to industry in 1973. Commercial seaweed farmers first succeeded in cultivating Eucheuma in the reef areas of Mindoro, Aklan, Cuyo, Zamboanga, and Tawi-Tawi.

Food and Agriculture Organization reports that seaweed farming is presently limited to a few countries in East Asia making it a high value crop with a high demand in the world market. The Philippines is noted for the culture of seaweeds along with Japan, China, Korea, and Taiwan.

390 Seaweed Species

Philippines, home to 390 species of seaweeds, have identified the numerous varieties as having economic value as food, animal feeds, fertilizers, diet supplement, medicines, and raw materials for industrial products.

60 varieties are edible, among them are gulamang dagat, gamet, pocpoclo, culot, lato, guso, barls-barls, bulaklak bato, and balbalolang. Some of these varieties are processed into jams, jellies, candies, pickles, baby’s food, and gulaman bars.

So far, four species – Halimada, Hypnea, Sargassum, and Asparagopsis – have been used as feed or fodder for livestock. Species of Cladophora, Enteromorpha, Chaetomorpha, and Gracilaria are used to supplement or substitute for fishfood for cultured herbivorous fish.

Residents of Tiwi, Albay have developed a pansit (noodles) made from seaweed, which has health benefits. The seaweed noodle is rich in calcium and magnesium andcan be cooked into pansit canton, pansit luglug, spaghetti and carbonara.

The high potassium content of brown seaweeds like Sargassum, Turbinaria, Hormophysa, and Hydroclathrus make them ideal substitutes for costly fertilizer.

In Kidapawan City, Jose Riga developed an all-purpose seaweed-based organic fertilizer and soil conditioner in stabilized pellets. The fertilizer is made from brown seaweed, cattle manure, stabilizing compounds and an organic binder fortified with soluble compounds of a number of nutrients.

Seaweeds are used to treat or prevent goiter, glandular troubles, stomach disorders, intestinal and bladder difficulties, unusually profuse menstrual flow, high-blood pressure, and high plasma-cholesterol level.

The Gracilaria species are used locally as pain relievers and ointments. It has been asserted that seaweeds may have curative properties for tuberculosis, arthritis, colds and influenza (or flu), worm infestations and even tumors. Currently, a number of research studies investigating these claims and other effects of seaweed on human health.

Some studies have found that seaweeds promote weight loss. For this reason, seaweed extract is used in some diet pills. Other seaweed pills work similar to gastric banding, they will expand in the stomach to make the body feel more full.

Commercially, seaweeds are valued for their colloids or gluey substance, particularly agar, carrageenan, and alginate. Both agar and carrageenan are extracted from red seaweeds, while alginate is extracted from brown seaweeds.

Agar is used in making jellied desserts, as stabilizer in pie fillings, piping gels, icings, cookies, cream shells, and as thickening and gelling agent in poultry, fish and meat canning. In the medical and pharmaceutical industries, agar serves as a laxative, suspending agent for barium sulfate in radiology, ingredient for slow-release capsules and in suppositories and surgical lubricants, and as a disintegrating agent in tablets. It is also used as impression materials to make accurate casts in prosthetic dentistry, criminology and tool manufacturing.

Carrageenan, on the other hand, is used in making ointments, as a stabilizing agent in frozen dairy products, as emulsifying agent in water-insoluble drugs and herbicides, and as texturing agent in toothpaste and powder.

Alginates enjoy many of the same uses as carrageenan, but are also used in production of industrial products such as paper coatings, adhesives, dyes, gels, explosives and in processes such as paper sizing, textile printing, hydro-mulching and drilling. In the biomedicine and pharmaceutical industries, alginates are used in wound dressings, and production of dental moulds and have a host of other applications.