## 4 Industrial Production of Caroenoid
### Carotenoids Function and Uses in Health and Pharmaceutical Industry  
Carotenoids have been widely used in the health industry. Photosynthetic organisms mainly produce carotenoids, which have the primary purpose of capturing light for photosynthesis purposes. Carotenoids, however, have a variety of secondary activities, one of which is to safeguard (photoprotect) photosynthetic organs against radiation damage. This is known as antioxidant activity, and it involves scavenging reactive oxygen species (ROS) such as the hydroxyl radical and hydrogen peroxide. This is the most commonly used biological function in human health [85; 86]. The chemical structure and interaction of substances with biological membranes in organisms provide antioxidant activity. Astaxanthin, fukoxanthin, zeaxanthin, sioxanthin, saproxanthin, myoxol, siphosanthin, and other carotenoid chemicals originating from the ocean have a significant potential to play a role in human health [86]. Astaxanthin produced by marine microalgae has antioxidant activity with various mechanisms, such as inhibiting the production of proinflammatory cytokines (nuclear factor kB, IL-1, IL-6, and TNF-), inhibiting the activity of the renin-angiotensin system, inhibiting the production of TGF-B1, and inhibiting the effect of antimicrobials in the body. Astaxanthin has enzyme targets within the cell in the form of superoxide dismutase (SOD) and catalase (CAT). Both enzymes play a role in reducing radical compounds in the body; SOD converts oxygen radicals (O\({}_{2}\).) to oxygen, and CAT breaks down H\({}_{2}\)O\({}_{2}\) into H\({}_{2}\)O and O\({}_{2}\), reducing the accumulation of harmful radical compounds [87; 88]. Astaxanthin is currently believed to have the potential to lower cancer risk and slow its progression. Astaxanthin has an anticancer impact on transplantable methylcholanthrene-induced fibrosarcoma (Meth-A tumor) cells, according to [PERSON] et al. [89]. Atherosclerosis is one of the diseases that is mediated or influenced by free radicals. Damage to the endothelium and the accumulation of low-density lipoprotein cholesterol (LDL-C) in the arterial walls are the main causes of atherosclerosis, although the inflammatory process is also involved. Inflammation, endothelial dysfunction, and vascular remodeling are all part of the pathophysiology of atherosclerosis. Nitric oxide (NO) inactivation and vascular NO bioavailability are linked to increased ROS. Astaxanthin has been demonstrated to improve endothelial function in resistant arteries, reduce oxidative stress, and increase NO bioavailability. Anti-obesity and immune system stimulation are two further benefits of astaxanthin for health [87; 90]. Fucoxanthin is a xanthophyll found in brown seaweeds (Phaeophyceae) such as _Undaria pinnatifida, Hijikia fusiformis, Laminaria japonica_, and _Sargassum fulvellum_. Because of its molecular structure, which includes allelic bonds, epoxy groups, and conjugated carbonyl groups in the polyene backbone, this pigment is known for its high antioxidant activity. Fucoxanthin were found to be effective in reducing risk factors for cardiovascular disease, including obesity, diabetes, hypertension, chronic inflammation, plasma levels, hepatic triglyceride levels, and cholesterol concentrations [86]. Fucoxanthin has been shown to have antiproliferative properties, suggesting that it could be used to treat cancer. Fucoxanthin induces the apoptotic cascade by promoting caspase cleavage and lowering _Bel-xl_ gene expression. PC-3 proliferation is inhibited by one of fucoxanthin's metabolites, fucoxanthinol. Halocymithiaxanthin, found in Halocyrhia roretzi, is a derivative metabolite of fucoxanthin. After having been proven to have a larger cytotoxic effect on human neuroblastoma cells (GOTO) than fucoxanthin, this metabolite has the potential to be used as an anticancer agent [87; 91]. One of the types of fucoxanthin metabolite is mytiloxanthin; this pigment is found in tunicates and shellfish. The antioxidant activity of this metabolite is higher than that of astaxanthin.