Algae have many economic uses including as a human food, animal feed, fertilizer, and in various industries. Some commonly used foods from algae include nori, kombu, and Irish moss. Algae are also used medicinally as antibacterial and anticoagulant agents. Environmentally, algae help treat sewage through photosynthesis and produce oxygen for animals. Algae products are found in foods, toothpaste, and pharmaceuticals through extraction of substances like carrageenan, alginic acid, and agar.

1. DEPARTMENT OF BOTANY
ALGAE : ECONOMIC IMPORTANCE
DR. RASIKA N. PATIL
ASSISTANT PROFESSOR
DEPARTMENT OF BOTANY
SHRI SHIVAJI COLLEGE OF ARTS COMMERCE AND SCIENCE AKOLA

3. INTRODUCTION
• Algae is a photosynthetic, eukaryotic marine organism. Their size ranges from unicellular
microalgae to giant kelp.
• Algae are characterized by their lack of flowers, formal roots, leaves, or even stems.
• They can grow anywhere such as in the dirt or on rocks, marine water, freshwater, etc.
• Algae are variable in shapes, sizes, and colors.
• There are several economic Importance of algae such as they are used as a food source, a
fodder, in fish farming, as a fertilizer and they also used in medical industries.

5. 1. Economic Importance of Algae in Food
A. As a Human Food
• Algae are used as a food. Most of the European countries such as Ireland, Scotland, France,
Germany, Norway, and Sweden considered algae an important source of nourishment.
• Algae are also used as the main ingredients in some local dishes in China and Japan. In those
countries, algae has become an important part of salad, accompanying meat in a fried dish, as a
topping on oatmeal, or even in liquid form as an extract in a nutritious smoothie.
• Algae is considered as a healthy food because of its nutrient values such as carbohydrates, fats,
proteins, and vitamins A, B, C, and E. Algae also contains minerals such as iron, potassium,
magnesium, calcium, manganese, and zinc.
• Many dairy products such as milk, ice cream, cheese, whipped topping, as well as syrup, icing, fruit
juice, etc. uses algae as an ingredient.

6. Names of Algal Which are used as Foods :
(a). Chlorella
• Chlorella get popularity after use in space research center and nuclear submarine to
generate oxygen.
• It is also famous for it’s nutrient value. It contains 30% carbohydrate, 30% protein, 15%
lipids, and also vitamin B and other nutrients. Which are essential for human beings as
well as animals.
(b). Laminaria
• It has 57% carbohydrate and is mostly used to prepare a popular dish known as ‘Kombu’.
(c). Chondrus
• It is an Irish moss and is cooked with milk and prepared in a popular dish known as
blancmanges.

7. d). Porphyria
• It is a seaweed of Rhodophyceae which contains 45% carbohydrate, 35% protein, and vitamin B.
• It is used to prepare a popular dish in japan named ‘Asakusa-Nori’(Porphyra tenera).
(e) Spirulina
• Spirulina is a blue-green algae that contains 60% protein, vitamin, and unsaturated fatty acid.
• In India Spirulina is available as a tablet.
(f). Spirogyra
• In south India, it is used to prepare a popular dish known as green laver.
• Spirogyra is commercially cultivated in Japan, Korea, and Taiwan, such as Ise Bay.
(g). Ulva
• In Japan, it is used as a salad.
(h). Nostoc
• In China, nostoc is used to prepare soup by boiling it.
(i). Monostroma
• It is a genus of marine green algae (seaweed), in Japan it is used to prepare a common food known
as ‘Aonori’.

8.  Economic Importance of Algae in Medicine
• Antibacterial agent Chlorellin is extracted from Chlorella. This antibacterial agent is
used to control coliforms and other related intestinal bacteria.
• Alaria helps in strengthening the stomach and restoring the appetite after sickness.
• Alginates is also used in the medicine industry for its haemostatic nature.
• The fucoidan and sodium lamanarin sulphate used as a ‘blood anticoagulant’.
• Digenia simplex, a Rhodophycean algae help in production of antihelmnitic drug.
• Extracts from Rhodomela larix and Ascophyllum nodosum are used to control both
gram positive and gram negative bacteria.
• There are present several algae which contain antibiotic or antibacterial properties
such as Halidrys, Pelvetia, Laminaria, Polysiphonia, Nitzschia and Hapalosiphon.

9. Importance of algae in Environment
 Sewage Disposal
• Sewage Disposal can be done by both physical and biological methods. The biological
method is a less expensive and easy way to dispose of sewage. The biological method is
accomplished by the partnership of legend bacteria.
• In sewage water, aerobic bacteria produce simple inorganic substances by breaking down
the complex organic substrates. These simple inorganic compounds are used up by the
photosynthetic algae. As a result, those receive the necessary oxygen for their activity.
• These photosynthetic algae also extract the ammonia from ammoniacal wastes and build
up their protein.
• Algae also increases the alkalinity of water by utilizing the minerals and carbon dioxide as a
result it decreases the percentage of bacteria in water.
• Algae also decreases the percentage of bacteria in sewage water by producing antibacterial
substances or extracellular substances, especially Chlorella.

11. Other Importance
• Photosynthetic algae produces oxygen which is important for
animals.
• Some algae help in the conversation of rocks to soil.

12. Algae Products
Algae is used as a key ingredient in various food products. The substance can either be used as an
additive or can act as a thickener in many types of food products. Algae can also be found in
household products, such as toothpaste and various pharmaceuticals. A type of algae, known as
carrageenan, is often added to dairy products such as cheese and sour cream in order to give
them a denser texture. Alginic acid, which can be found in algae, is used to stabilize foods such as
milkshakes, malts, and mayonnaise. Consumers might also be familiar with the green paper-like
sheets used to wrap sushi. This product, called nori, is actually a leafy form of algae which was
traditionally grown in Japan and contains plenty of healthy nutrients and assorted vitamins.
Gelatin is used in the production of numerous edible products. In fact, this substance is made up
of a type of algae known as agar. Purportedly first used in 17th century China, gelatin acts to
solidify liquids found in such popular products such as pie crusts and fillings.
Purple-colored algae, also known as Porphyra, is commonly used in Japan and is known as nori,
which is used to wrap up sushi rolls. In Korea, this same substance is known as gim. In Wales, this
type of algae is referred to as laverbread, which is traditionally served for breakfast along with
bacon and cockles (a type of mollusk). In Ireland, residents stew or boil the algae, thus making it
into a pink colored jelly.
In the manufacturing of toothpaste, algae is used in order to thicken what would otherwise be a
runny substance and transform it into a partially solid form. This particular form of algae is safe
to consume and dissolves during the tooth brushing process.

16. THANK YOU