Potential Biotechnological Applications of Cyanobacterial Exopolysaccharides

Abstract The cyanobacterial exopolysaccharides (EPSs) are considered as one of the important group of biopolymers having significant ecological, industrial, and biotechnological importance. Cyanobacteria are regarded as a very abundant source of structurally diverse, high molecular weight polysaccharides having variable composition and roles according to the organisms and the environmental conditions in which they are produced. Due to their structural complexity, versatility and valuable biological properties, they are now emerging as high-value compounds. They are possessing exceptional properties and thus are being widely explored for various applications like in food and pharmaceutical industries, in bioremediation for removal of heavy metals, for soil conditioning, as biopolymers, bioadhesives, and bioflocculants. However, poor understanding of their complex structural properties, lack of concrete information regarding the genes encoding the proteins involved in the EPS biosynthetic pathways, their process of production and about the associated factors controlling their structural stability, strongly limits their commercialization and applications in the various fields of biotechnology. Owing to the above context, the present review is aimed to organize the available information on applications of cyanobacterial EPSs in the field of biotechnology and to identify the research gaps for improved industrial utilization and commercialization of these biomaterials.

Application of adhesive materials in biomedicine: progress and prospects / 生物工程学报

As an important auxiliary material, adhesive materials have many important applications in various fields including but not limited to industrial packaging, marine engineering, and biomedicine. Naturally occurring adhesives such as mussel foot proteins are usually biocompatible and biodegradable, but their limited sources and poor mechanical properties in physiological conditions have limited their widespread uses in biomedical field. Inspired by the underwater adhesion phenomenon of natural organisms, a series of biomimetic adhesive materials have been developed through chemical or bioengineering approaches. Notably, some of those synthetic adhesives have exhibited great promise for medical applications in terms of their biocompatibility, biodegradability, strong tissue adhesion and many other attractive functional properties. As natural adhesive materials possess distinctive "living" attributes such as environmental responsiveness, self-regeneration and autonomous repairs, the development of various biologically inspired and biomimetic adhesive materials using natural adhesives as blueprints will thus be of keen and continuous interest in the future. The emerging field of synthetic biology will likely provide new opportunities to design living glues that recapitulate the dynamic features of those naturally occurring adhesives.

Cut and paste: A novel method of re-attaching rectus muscles with cyanoacrylate during recessions in strabismus.

Aim: Bio-adhesives like cyanoacrylate offer an alternative to sutures to attach tissues, including in ophthalmology. This prospective trial evaluated the suitability and bio-tolerance of iso-amyl cyanoacrylate in rectus muscle recession surgery for strabismus. Materials and Methods: We randomized one eye in each of 10 cases of bilateral horizontal rectus recessions to 6/0 polyglactin and the other to iso-amyl-cyanoacrylate. We compared time to reattachment (from disinsertion), complications and inflammatory scores (0 to +3: nil, mild, moderate and severe) on Day One, at two and at four to six weeks post surgery. Results: There were no significant group differences in inflammatory scores (Wilcoxon, all values of P>0.05). All attachments held firm. Gluing took significantly longer by 5.24±1.91 min (95% CI for difference: 3.87-6.61). There were no complications. Conclusion: We feel that although it takes marginally longer, iso-amyl cyanoacrylate offers an effective and safe alternative to sutures for muscle recession in strabismus surgery. Since it is cheaper (vs. polyglactin) and offers multi-use possibility it may also prove to be cost-effective.