Eucheuma denticulatum is a type of red algae found in the Philippines, tropical Asia, and the western Pacific.
It’s a primary source of iota carrageenan, which is used in various industries such as food and beauty products.
When cultivated, Eucheuma denticulatum is also known as E. spinosum and is found in different colors like brown, green, and red.
How Is Eucheuma denticulatum Cultivated?
The cultivation of Eucheuma denticulatum started in the Philippines in the early 1970s and has since spread to other locations.
There are different methods of cultivating this algae, with one common method being the off-bottom ‘tie-tie’ method.
This involves driving two stakes into the sediment and attaching a rope between them.
Pieces of the seaweed are then tied to the rope at regular intervals and allowed to grow for 6 weeks before harvesting and drying.
What Is the History and Geographic Distribution of Eucheuma denticulatum?
E. denticulatum was first described as Fucus denticulatus in 1768 by Nicolaas Laurens Burman and later transferred to the genus Eucheuma in 1917.
It originally occurred only in the Indian Ocean, South-East Asia, and neighboring parts of the western tropical Pacific.
It has since been distributed further eastward by humans into the Pacific, including Hawaii, Micronesia, and Christmas Island in easternmost Kiribati.
In South-East Asia, E. denticulatum is found in Peninsular Malaysia, Singapore, Indonesia, the Philippines, and Vietnam.
In Indonesia, farming trials before 1984 failed, but now the largest production area is around Bali.
What Are the Uses of Eucheuma denticulatum?
E. denticulatum is mainly used as a source of iota carrageenan, which becomes an ideal type of carrageenan after alkali modification.
Carrageenan is used in industrial food and beauty aid products, pet foods, and various formulations.
E. denticulatum can also be eaten fresh or blanched and mixed with salad garnish, made into ‘Eucheuma candy’ or ‘kue,’ or used as a garnish for other dishes such as fish.
In some areas, E. denticulatum is also used as fertilizer and in controlling heavy metal pollution by absorbing metals like lead and cadmium.
How Is Eucheuma denticulatum Produced and Traded Internationally?
The Philippines and Indonesia are the two main producers of E. denticulatum.
Annual production through phycoculture in the Philippines was about 8173 tons in 1986 and rose to 20,190 tons by 1994 (all wet weights).
In Indonesia, E. denticulatum and Kappaphycus alvarezii are farmed with equal ease.
Most of the E. denticulatum crop is exported as raw material (dried seaweed) to processors in Europe and the United States.
Since 1978, however, carrageenan has also been produced in the Philippines, with Indonesia following in 1988.
What Are the Properties of Eucheuma denticulatum?
Extracts of E. denticulatum have shown antitumor activity against Ehrlich carcinoma with an inhibition rate of 41.2%.
The algae contain various nutrients and minerals, such as crude fat, crude protein, crude iodine, ash, crude fiber, nitrogen, mannitol, potassium, sodium, calcium, magnesium, phosphorus, zinc, copper, iron, and manganese.
E. denticulatum also produces hydrogen peroxide and releases various volatile halocarbons under oxidative stress conditions.
These compounds can be efficient in catalyzing stratospheric ozone removal.
How Does Eucheuma denticulatum Grow and Develop?
The growth of E. denticulatum is initiated by a group of apical cells. The average daily growth rate in open-air phycoculture in the Philippines is 1% to 5%.
Optimal growth conditions include temperatures of 24°C to 30°C, high solar energy levels, a pH of 8, and a salinity of 32%.
Nitrogen and phosphate levels should also be within specific ranges for optimal growth.
Haploid male and female gametophytes are produced from meiospores released by tetrasporophytes, suggesting a genetic determination of sexual phenotypes.
However, most specimens used in phycoculture are sterile and propagate by fragmentation.
What Are the Challenges and Prospects for Eucheuma denticulatum Cultivation?
Challenges for Eucheuma denticulatum cultivation include diseases such as ‘ice-ice,’ which can wipe out entire crops, as well as grazing by fish and invertebrates.
Environmental factors like water temperature, light intensity, and nutrient availability can also affect growth and production.
Despite these challenges, the high demand for iota carrageenan on the world market and the Chinese food market makes E. denticulatum a valuable crop.
Future prospects for this algae include selecting new strains for genetic improvement and addressing the ecological impacts of intensive Eucheuma farming.
Eucheuma denticulatum Characteristics
|Required Lighting:||Moderate High|
|Required Water Flow:||Moderate|
|Maximum Size:||12 in (30.5 cm)|