NICAboard

Aquaculture and Fisheries News => Aquaculture News => ข้อความที่เริ่มโดย: Nicaonline ที่ มกราคม 21, 2007, 03:42:23 PM



หัวข้อ: Is seaweed the solution?
เริ่มหัวข้อโดย: Nicaonline ที่ มกราคม 21, 2007, 03:42:23 PM
Source: Delaware Online  World News    21/01/2007 14:42:42

Deborah Gates

If a global appetite for sushi helped propel nori into a $2 billion annual production, imagine the financial reward from a seaweed that could cure cancer or feed a starving nation.



Madhumi Mitra can. And in a second-floor laboratory at the University of Maryland Eastern Shore, she and a team of research students are dissecting varieties of the slimy sea vegetables for clues to their hidden power. For years scientists have known that seaweeds, a form of macroalgae, aid in the cure of many of the world's medical and environmental woes.



What remains a mystery are the properties and how, to what degree and in what doses edible seaweeds add value.



Mitra, a UMES assistant professor of biology and environmental science in the Department of Natural Sciences, is as sure as anything that beneath the coastal bays of Worcester and Sussex counties lies the answer -- and a potential fortune.



"No one has done a systematic biochemical study on the three species; there have been scattered studies, but no information on seasonal data of their properties, dietary fiber or other nutritional composition," Mitra said this week, slumped over a microscope in the Food Science and Technology building at UMES in Princess Anne. "In Japan, there is testing of HIV with seaweed and in patients there has been some improvement. I can't guarantee that if you start a seaweed harvesting business, you'll become a millionaire. But, the more we discover, the more it would lead to innovations."



She couldn't have chosen a more ideal place than the Eastern Shore to conduct the four-year, seaweed interdisciplinary project: a $300,000 U.S. Department of Agriculture-funded study of the properties of edible seaweeds and their impact on waterways, health, nutrition and aqua-farming. UMES research will be conducted through 2008 by her department in conjunction with the UMES Department of Food Science and Technology, led by Jurgen Schwarz.



Under a rock



Seaweed harvesting as a business could be a way to reduce the abundance of the macroalgae that sucks in oxygen and could lead to fish kills and other environmental problems, said Roman Jesien, science coordinator for the Maryland Coastal Bays.



"If there is an abundance of nutrients in the water, there tends to be more macroalgae," he said. "There used to be a lot less, but we are seeing more nutrients. Aqua-culture could be an alternative way to decrease it."



Methods to control runoff and restore oxygen have sparked political feuds and debates between agricultural and environmental groups over how and where to spread farm manure.



Until now, there have been few, if any, attempts to separate and evaluate the properties of three basic groups of edible seaweeds -- red, brown and green -- to understand exactly what in their composition benefits nature and man, Mitra said.



Matilda Madden combs the depths of the Chincoteague Bay on the Eastern Shore of Virginia off Worcester County and the Indian River Bay in nearby Sussex County in Delaware, collecting varieties of seaweed at different times of year.



Under rocks in the shallows, the UMES graduate student working on a doctorate degree in marine studies wants to examine the "seasonality" of the macroalgae or "how they change with the seasons" for research into the nutritional composition of seaweeds on the Delmarva Peninsula at varying intervals.



"I collect samples from the general population; I hope that globally, seaweeds can be grown as a crop," she said.



Beneath the deep



Chris Havrilla, an undergraduate student in biology education, assists project participants and monitors moisture levels in seaweeds with a contraption similar to a hospital X-ray device. He hopes his contribution helps change the world.



"I wasn't interested necessarily at first, but there are claims of health and medical benefits and I want to know what values there are," said Havrilla, who last spring spent two weeks at Emory University where he tested protein, fat and ketone levels in seaweed samples from the coastal bays on a piece of special laboratory equipment.



"The tests confirmed some speculations about the differences and similarities of some species," Havrilla said.



A 1999 Maryland Department of Resources vegetation study identified up to 25 species of macroalgae in each of Maryland's five coastal bays, Jesien said. The vegetation was in abundance and sucking in oxygen that sustains other sea life, indicating that algae continued to thrive on nutrients seeping into the bays from fertilizers that run off farmland, he said.



"It is a nutrient indicator, a bellwether to see how much nutrients are in the water," Jesien said. "It is telling us there is too much."



Anish Chaudhuri, a marine estuarian environmental science doctorate student, combs the coastal bays for mercury, lead, copper, zinc and other metals. He hopes to determine seaweeds' ability to absorb the elemental sources of water pollution.



Medical wonder?



So far, Chaudhuri has detected that despite the region's recreational boating industry, levels of metal in the waters tested low.



Plentiful in the coastal bays is sea lettuce, a green edible seaweed used, among other things, as a food thickener. However, Jesien says little is known about its nutritional value, if any.



"There is a lot of that in the bays and it's used in a number of cultures for food," he said. "Some people eat it raw, but it's kind of like herbs -- people use it for a variety of things, but what is it?"



A thyroid disorder several years ago piqued Lesley Bensinger's interest in seaweeds. She saw a doctor, but also ingested kelp, a brown edible seaweed used in soap and glass production and as a thickener for ice cream, jelly and toothpaste.



"I was interested in alternative medicine and I knew seaweed had medical value," Bensinger said. "I first ate seaweed as a medicinal alternative; it was a kelp supplement. I improved."



In the UMES project, the marine and estuarian environmental science master's student intends to determine the difference between seaweeds and so-called sea grass, also known as submerged aquatic vegetation, or SAV.



"Seaweed has spores and germinates," she said. "I'm studying the relationship between seaweed and sea grass."



Eventually, farmers would be able to harvest quantities and varieties for specific pharmaceutical and nutritional purposes, or just for the pleasure of eating seaweeds, like the thin sheet of dried seaweed known as nori that wraps a sushi roll, Mitra said. She considered the number of Japanese restaurants when she arrived in Salisbury in 1999.



"There was not a single Japanese restaurant; now there are three or four and they serve sushi," Mitra said. "Seaweeds are the food of the past, present and future. We intend to identify their properties and understand how and why."



The coastal bays is the hot spot to find out, agrees Jesien: "There is so much of it here, we should figure out what to do with it."


Source or related URL: http://www.delawareonline.com