beta-Glucan nanoparticles were produced from cereal and fungal sources viz: oats, barley, and yeast using ball milling which is considered as a green technology. The beta-glucan nanoparticles were evaluated using dynamic light scattering (DLS) and Fourier transform infra-spectroscopy (ATR-FTIR). The particle size, zeta potential, polydispersity index, antioxidant, anticancerous, antimicrobial and antihypertensive potential of beta-glucan nanoparticles from different sources were also studied. The experimental results revealed that the average particle size for BN (Barley beta-glucan nanoparticle), ON (Oats beta-glucan nanoparticle), and YN (Yeast beta-glucan nanoparticle) were 90.35, 83.55 and 77.44 nm and zeta potential were in the range of -27 to -6.3 mV. . There was an increase in antioxidant, antihyperglycemic and antihypertensive activity of BN, YN, and ON in comparison to native. Study reported increase in anticancerous activity upon size reduction. Also, antibacterial activity of BNT, ONT, YNT, BN, ON and YN against Gram-negative and Gram-positive (E.coli & Bacillus Subtilis) were studied. It was concluded that the beta-glucan nanoparticles showed enhanced nutraceutical properties that might be due to the nanoreduction using green technology.