Figure 2.

The red and brown algae macrophytes are abundant sources of biologically active metabolites, including steroids. Here, we highlight some representative examples: (a) Laurencia pacifica (red alga, Rhodophyceae). This species is known for producing halogenated metabolites, such as sesquiterpenes, diterpenes, triterpenes, and C15 acetogenins. (b) Laminaria digitata (brown alga, Phaeophyceae). A commonly consumed brown algae, particularly in coastal regions, with kelp that is rich in terpenoids, essential amino acids, polyunsaturated fatty acids, carbohydrates, vitamins, and minerals such as iron and calcium. (c) Sargassum sp. (brown alga, Fucales). Various species of the Sargassum genus are utilized for human nutrition and serve as a valuable source of steroids, proteins, vitamins, carotenoids, and minerals, and Professor Dembitsky collected the biological material in Southern California, summer 2018. (d) Ulva lactuca (sea lettuce, green alga, Ulvaceae). Cultivated in China, Republic of Korea, and Japan, sea lettuce is consumed by manatees, sea slugs, and shellfish. Extracts of this edible green algae contain bioactive components, including steroids and triterpenoids. (e) Enteromorpha intestinalis (green bait, sea lettuce, green alga, Ulvaceae). This green alga, commonly known as green bait or sea lettuce, produces a wide range of terpenoids, including steroids. (f) Gracilaria pacifica (red spaghetti, red alga). Widely used in the cosmetic industry for shampoos, creams, soaps, and sunscreens, this red alga contains terpenoids and carotenoids and serves as a source of high-quality agar.