Isolation of β-glucan from Eleusine coracana and its antibiofilm, antidiabetic, antioxidant, and biocompatible activities.

Eleusine coracana (Finger millet) has high nutritional value with numerous health benefits and is of low cost. Isolation of beta-glucan (βG) from E. coracana (Ec-βG) has gained increasing research attention. UV-vis spectroscopy used to measure the surface plasmon resonance at 361 nm to confirm the presence of polysaccharides (glucan molecules) in Ec-βG. X-ray diffraction analysis of Ec-βG displayed a crystalline nature and confirmed the presence of the βG molecule. Further, the bioactive compounds of Ec-βG were screened using gas chromatography-mass spectrometry. The antibacterial activity of Ec-βG against both Gram-positive (Lysinibacillus fusiformis, Enterococcus faecalis) and Gram-negative (Proteus vulgaris, Shigella sonnei) bacteria were assessed through minimum inhibitory concentrations <70 μg/ml of Ec-βG. In addition, the antibiofilm activity and bacterial viability of Ec-βG at 100 μg/ml was confirmed by light and confocal laser scanning microscopy. Furthermore, Ec-βG inhibits α-amylase and α-glucosidase at an IC₅₀ -value of 1.23 and 1.42 μg/ml, respectively. Superoxide anion scavenging activity at IC₅₀-1.4 μg/ml and DPPH radical scavenging activity at IC_50-1.2 μg/ml showed that Ec-βG had potential antioxidant property. The in vitro hemolysis assay for biocompatibility of Ec-βG at 200 μg/ml showed 0.06 ± 0.09%. Therefore, Ec-βG has the potential to act as a suggestive agent for antibacterial, antidiabetic, and antioxidant activity.