Cellulose nanofibers have been processed from renewable feedstock in particularly from natural fibers, root crops and agro fibers, wherein the pulp was hydrolysed at a moderate temperature of 50 to 90 degree C., one extraction was performed using dilute acid and one extraction using alkali of concentration less than 10%; and residue was cryocrushed using liquid nitrogen, followed by individualization of the cellulose nanofibers using mechanical shear force. The nanofibers manufactured with this technique have diameters in the range of 20-60 nm and much higher aspect ratios than long fibers. Due to its lightweight and high strength its potential applications will be in aerospace industry and due to their biodegradable potential with tremendous stiffness and strength, they find application in the medical field such as blood bags, cardiac devices, valves as a reinforcing biomaterial.