What is Red Algae?

Rhodophyta algae, about 3,000 species. Red algae, most of which are multicellular and very few are single-celled algae. Algae purple, rose red, dark red and other colors. Most of the red algae grow in the ocean and are widely distributed with many species. According to statistics, there are about 558 genera and more than 3740 species. They are divided into two subclasses: Bangioideae and Floridae . Many of them have important economic value. In addition to food, it is also a raw material for medical, textile, food and other industries.

Red algae has important economic value. In addition to eating,

Recently, researchers at the National University of Busan in South Korea discovered that red algae extract (Gelidium amansi extract, GAE) can inhibit high-fat diet-induced obesity. Earlier studies have confirmed that intake of GAE-containing

Not produced in red algae life history

Porphyridium

Belongs to the subclasses Porphyridium. The plant body is single-celled, the cell center or oval. The chromophore is star-shaped, with a central axis, a protein core, and no starch sheath. It often lives on wet ground and corners, and can be used for pure culture.

Porphyra

It belongs to the subclass of Porphyra. The algae are single-layer or two-layer cells, which are purple-red, purple, or purple-blue. The base is fixed to the substrate with anchors. It has no stalks or short stalks. Generally it is 20 30cm, 10-20cm wide. The cells are mononuclear, with 1 or 2 stellar pigment bodies, central axis, and protein nuclei. Algae grow diffusely. Commonly distributed and cultivated laver in our country are sweet laver, cabbage and laver. Take P. tenera as an example to understand the life history of Porphyra. Sweet laver is a hermaphrodite plant. When the water temperature is about 15 , it produces sexual organs. Any one of the vegetative cells of the algal body can be transformed into a sperm sac, and its protoplasts divide to form 64 sperm. The fruit sac is formed by a normal vegetative cell with a slight metamorphosis. One end is slightly bulged and protrudes from the surface of the algal colloid, that is, the fertilized filament. There is an egg in the fruit sac. After the sperm is released, it floats on the fertilized silk with the current, enters the fruit cell and combines with the egg to form a double zygote. The zygote undergoes meiosis and ordinary division to form 8 haploid spores. After the spores mature, they fall on the shell of the clam, oyster, or other mollusk, germinate into the shell, and grow into single-line branched filaments. That is, schizophyllum; schizophyllum produces conchospore, which germinates into small laver in summer, with a diameter of about 3mm. When the water temperature is about 15 ° C, the spore can also directly develop into large laver. In summer, due to the high temperature in the water, it cannot develop into large laver. Small laver produces monospores and develops into small laver. When the water temperature is about 15 in late autumn, the monospores germinate into large laver. Therefore, in the north, the growth period of large laver is from November to May each year.

Polysiphonia

It belongs to the subgenus Eugenia of the genus Rhodophyta. It is the most common algae in seawater. There are about 150 species in this genus. The plant body is a filamentous body with multiple rows of cell branches. Some kinds of filamentous body are differentiated into erect filamentous bodies and filiform bodies. The base is fixed to a rock by the sea with a single cell pseudoroot, about 3-20 cm high. The center of the filament is composed of a row of thicker cells, called the central siphon, and its periphery is surrounded by 4-24 thinner cells, which is called the peripheral siphon.

Plants of the genus Organophyllum include haploid female and male gametophytes, diploid fruit sporophytes, and tetrasporites. The gametophyte and the tetrasporium are identical in appearance, and they are typical homomorphic generations. Sperm sacs are born on the fertile branches of the upper part of the male gametophyte, and fruit cells are born on the fertile filaments of the upper part of the female gametophyte. When the spores are produced, a special peripheral axis cell (also called a support cell) is born next to the central axis cell of the filamentous body. From this cell, 4 cells of carpogonial filaments are produced. The apical cells of mycelium are fruit cells with fertilized filaments. The fruit cell nuclei divide into two, the lower nuclei are fruit nuclei, and the upper nuclei are fertilized nuclei, and this nuclei degenerate later. Sperm enter the fruit cell from the fertilized filament and combine with the egg. At the same time, the supporting cells give birth to several cells called helper cells. The fruit cell is connected to the support cells through the helper cells below it. The zygotic nucleus divides into two, enters the supporter cell, and continues to divide in this cell, with the remaining nuclei degenerating. At this time, many sporulation filaments occurred in the supporting cells, and the nuclei in the supporting cells moved to the sporulation filaments. Fruit sporangia are formed at the end of sporulation silk, and there are 2 nuclei in each sac. At the same time, the supporting cells fuse with surrounding cells to form sporangia clumps, which are collectively called cysts (ie, fruit sporophytes). Fruit spores germinate and form diploid Tetraspores. A tetrasporocyst is formed on the tetraspore body, and after meiosis, 4 haploid spores are formed, which are called tetraspores. The tetraspores germinate to form male and female gametophytes.

Common aquatic species in red algae are Batrachospermum, marine species include Nemalion, Corallina, Ceramium, Rhododoma, and Cauliflower Genus (Gelidium).

Rhodophyta

The economic value of red algae is very high. Among red algae, laver is a kind of edible algae, it is rich in protein, not only rich in nutrition, but also delicious. In addition, Glidium amansii and Gloiopeltis furcata can be eaten. Amaranth (Caloglossa leprieurii) and seaweed (Digenea simples) are common pediatric insect repellents. Agar extracted from plants of the genus Cauliflower, Gracilaria, and Eucheuma is used in the pharmaceutical industry and textile industry, and is widely used as a culture medium.