Nutraceuticals provide significant potential in enhancing health and mitigating ailments, rendering them a vital inclusion in the contemporary healthcare domain. Nutraceutical polymers derived from microbes including bacteria, fungi, and microβalgae are one of the versatile and sustainable bioactive compounds with promising healthcare benefits. β-glucan is one of the microbial polymer nutraceuticals belongs to polysaccharides and possesses several advantageous health features, including the ability to prevent and treat specific digestive ailments and enhance the immune system. The biological activity of this chemical is influenced by factors such as its size, molecular weight, conformation, bond frequency, solubility, and structural modifications. β-glucan lowers cholesterol and glucose levels in the bloodstream, hence decreasing the likelihood of developing cardiovascular disease and diabetes. β-glucan not only affects lipid levels and glucose metabolism, but it also has antioxidant capabilities by eliminating reactive oxygen species. This reduces the risk of several illnesses such as atherosclerosis, cardiovascular diseases, neurodegenerative disorders, diabetes, and cancer. However, the widespread use of these polymer nutraceuticals is limited due to limits in their availability and difficulties in extracting them from these microorganisms. This chapter emphasizes the importance of β-glucan as powerful agent for a diverse array of nutraceuticals and their potential in mitigating numerous health problems. The chapter discusses the chemistry, biosynthesis, extraction, and identification of these polymers together with exploring their potential to be used in nutraceuticals and therapeutic applications.