Isolation, structures and biological activities of polysaccharides from Chlorella: A review

Chlorella, a green microalga, has been used as an important ingredient in food and medicine because of its excellent nutritive and functional properties. Polysaccharides, as major active ingredients of Chlorella, have attracted increasing attention due to their various health promotion activities, such as those associated with immunomodulation, antioxidation, anti-hyperlipidemia, antitumor, neuroprotection, and anti-asthmatic effect. The significance of polysaccharides from various species of the Chlorella genus has been extensively reported by the scientific community from the perspectives of extraction, structural features, biological activities, and potential uses, which need to be reviewed to improve the understanding, development and utilization of these species. Therefore, this review aims to comprehensively summarize previous and current references regarding the extraction, purification, structural characterization and biological activities of polysaccharides from Chlorella. Moreover, this review also highlights the challenges of investigation and future considerations for holistic utilization in food and medicine.