## 4 Applications of _Chlorella vulgaris_ in Food, Feed, and Medicine
### Applications in Medicine  
Beyond its nutritional benefits, _C. vulgaris_ exhibits significant potential for therapeutic applications, spanning from immune modulation to cancer prevention [9]. Its bioactive compounds, including chlorophyll, carotenoids, and polysaccharides, have been extensively studied for their anti-inflammatory, antioxidant, antiviral, and anticancer properties [4; 123]. In particular, the anti-inflammatory properties of _C. vulgaris_ are crucial, especially considering that inflammation is a key factor in developing chronic diseases like arthritis and cardiovascular diseases. Persistent inflammation can lead to tissue damage and exacerbate disease progression. _C. vulgaris_ offers a potent anti-inflammatory solution by inhibiting pro-inflammatory cytokines, such as TNF-\(\alpha\) and IL-6, and downregulating COX-2 activity. Additionally, it modulates the NF-kB pathway, increasing the production of anti-inflammatory cytokines like IL-10, which aids in tissue repair and reduces inflammation. This comprehensive approach may not only alleviate symptoms but also target the root causes of inflammation, positioning _C. vulgaris_ as a promising candidate for integrative treatment strategies in managing chronic conditions. Another notable medicinal application of _C. vulgaris_ is its ability to support immune health. Studies suggest that regular consumption can enhance innate and adaptive immunity by stimulating the activity of NK cells, macrophages, and T cells. This makes it valuable in preventing infections and supporting immune function, particularly in immunocompromised individuals or those facing chronic illnesses [21]. Additionally, _C. vulgaris_ has demonstrated notable antiviral activity, particularly against enveloped viruses such as herpes simplex virus (HSV), hepatitis C virus, and HIV. Research indicates that sulphated polysaccharides can effectively prevent viral adsorption and replication, thereby blocking the initial stages of viral infection [41; 42]. This mechanism is particularly relevant for enveloped viruses, which rely on specific interactions with host cell receptors for entry. The sulphating of polysaccharides enhances their ability to mimic heparan sulphate, a natural component on cell surfaces that many viruses exploit for attachment [41]. Antiviral activity is often correlated with the degree of sulphating, indicating that modifications to the polysaccharide structure can enhance their efficacy against these viruses [43]. Sulphated polysaccharides isolated from _Chlorella_ have been shown to inhibit viral replication by preventing viruses from penetrating host cells. This antiviral activity highlights _Chlorella_ as a promising candidate for the development of antiviral therapies, especially in an era where emerging viral threats pose global health challenges [4]. In terms of anticancer potential, _C. vulgaris_ compounds like carotenoids and chlorophyll play a key role. These compounds have been shown to induce apoptosis (programmed cell death) in cancer cells and inhibit tumor proliferation. _Chlorella_'s ability to reduce ox idative stress, inhibit angiogenesis (the formation of new blood vessels that feed tumors), and activate pro-apoptotic pathways positions it as a potential adjunct therapy in cancer treatment. Research has shown that these compounds can reduce DNA damage, inhibit tumor growth, and enhance the body's natural defenses against cancer [18]. Furthermore, _C. vulgaris_ has demonstrated significant benefits in managing chronic diseases such as cardiovascular conditions and type 2 diabetes [17]. Its lipid-lowering effects help reduce total cholesterol, LDL cholesterol, and triglycerides while simultaneously increasing HDL cholesterol. These effects, combined with its anti-inflammatory properties, contribute to the prevention of atherosclerosis and promote heart health [3,86]. Additionally, _C. vulgaris_ supplementation has been associated with improved glycemic control in individuals with type 2 diabetes.