Microbial biofilm: A matter of grave concern for human health and food industry.

Pathogenic microorganisms have adapted different strategies during the course of time to invade host defense mechanisms and overcome the effect of potent antibiotics. The formation of biofilm on both biotic and abiotic surfaces by microorganisms is one such strategy to resist and survive even in presence of antibiotics and other adverse environmental conditions. Biofilm is a safe home of microorganisms embedded within self-produced extracellular polymeric substances comprising of polysaccharides, extracellular proteins, nucleic acid, and water. It is because of this adaptation strategy that pathogenic microorganisms are taking a heavy toll on the health and life of organisms. In this review, we discuss the colonization of pathogenic microorganisms on tissues and medically implanted devices in human beings. We also focus on food spoilage, disease outbreaks, biofilm-associated deaths, burden on economy, and other major concerns of biofilm-forming pathogenic microorganisms in food industries like dairy, poultry, ready-to-eat food, meat, and aquaculture.

Self-cross-linked starch/chitosan hydrogel as a biocompatible vehicle for controlled release of drug.

A facile one-pot approach was adopted to prepare a polysaccharide-based hydrogel of oxidized starch (OS)-chitosan. The synthetic monomer-free, eco-friendly hydrogel was prepared in an aqueous solution and employed for controlled drug release application. The starch was first oxidized under mild conditions to prepare its bialdehydic derivative. Subsequently, the amino group-containing a modified polysaccharide, "chitosan" was introduced on the backbone of OS via a dynamic Schiff-base reaction. The bio-based hydrogel was obtained via a one-pot in-situ reaction, where functionalized starch acts as a macro-cross-linker that contributes structural stability and integrity to the hydrogel. The introduction of chitosan contributes to stimuli-responsive properties and thus pH-sensitive swelling behavior was obtained. The hydrogel showed its potential as a pH-dependent controlled drug release system and a maximum of 29 h sustained release period was observed for ampicillin sodium salt drug. In vitro studies confirmed that the prepared drug-loaded hydrogels showed excellent antibacterial ability. Most importantly, the hydrogel could find potential use in the biomedical field due to its facile reaction conditions, biocompatibility along with controlled releasing ability of the encapsulated drug.