Microalgae

Microalgae, also called microphytes, are tiny microscopic algae that are too small to see with the naked eye. They float in freshwater and marine systems, living either in the water column or in the sediment. These unicellular organisms can exist alone or in chains and range from just a few micrometers to a few hundred micrometers in size.

Through photosynthesis, microalgae play a vital role in our world by producing about half of the oxygen we breathe and using greenhouse gas carbon dioxide to grow. They form the base of the food web, supporting all the trophic levels above them. Because they contain chlorophyll and need sunlight, they often float near the ocean's surface where the sun shines. Microalgae also need nitrates, phosphates, and sulfur, which they turn into important nutrients like carbohydrates, fats, and proteins.

The biodiversity of microalgae is huge, with estimates suggesting between 200,000 and 800,000 species exist, though only about 50,000 have been described. They produce many valuable compounds such as carotenoids, fatty acids, enzymes, and sterols. These compounds can be used in foods, agricultural products, and even as a source for biofuels. Microalgae also show promise in cleaning up the environment through bioremediation. Some types of microalgae have special properties that may help protect health, such as fighting diseases and supporting heart health.

Characteristics and uses

Microalgae are tiny plants that float in water, changing their makeup based on where they live and what is around them. They can adjust their chemistry to survive in different conditions, like when there isn’t enough phosphorus, a type of nutrient.

People use microalgae in many ways, even though most aren’t safe to eat directly. They help make plant food better for growing crops and are used in beauty products that keep skin healthy. In medicine, microalgae help create important compounds that can be used to treat health problems. They also help clean the water by turning carbon into food for other sea creatures and giving us oxygen. Even the omega-3 fats found in fish come from the tiny algae that fish eat.

Cultivation of microalgae

Main article: Culture of microalgae in hatcheries

Microalgae can be grown in both closed systems and open ponds. Open ponds are often chosen because they cost less money. Many types of microalgae are grown in special places called hatcheries and are used for many important things, like food for people, fuel, helping grow fish and plants, making medicines, and creating beauty products.

Scientists study what helps microalgae grow best. They look at the size and shape of the growing space, how much light the algae get, the amount of a gas called carbon dioxide, the nutrients they need, and how the water is mixed.