Mulberry Leaves (Morus Rubra)-Derived Blue-Emissive Carbon Dots Fed to Silkworms to Produce Augmented Silk Applicable for the Ratiometric Detection of Dopamine.

Silk fibers (SF) reeled from silkworms are constituted by natural proteins, and their characteristic structural features render them applicable as materials for textiles and packaging. Modification of SF with functional materials can facilitate their applications in additional areas. In this work, the preparation of functional SF embedded with carbon dots (CD) is reported through the direct feeding of a CD-modified diet to silkworms. Fluorescent and mechanically robust SF are obtained from silkworms (Bombyx mori) that are fed on CDs synthesized from the Morus rubra variant of mulberry leaves (MB-CDs). MB-CDs are introduced to silkworms from the third instar by spraying them on the silkworm feed, the mulberry leaves. MB-CDs are synthesized hydrothermally without adding surface passivating agents and are observed to have a quantum yield of 22%. With sizes of ≈4 nm, MB-CDs exhibited blue fluorescence, and they can be used as efficient fluorophores to detect Dopamine (DA) up to the limit of 4.39 nM. The nanostructures and physical characteristics of SF weren't altered when the SF are infused with MB-CDs. Also, a novel DA sensing application based on fluorescence with the MB-CD incorporated SF is demonstrated.

Adhesion and cellsurface properties of wild species of spore formers against enteric pathogens.

OBJECTIVE: To investigate the adhesion potential and cell surface properties against enteric pathogens Salmonella typhi, Salmonella para typhi A and Vibrio cholera. METHODS: Adhesion potentials of spore and vegetative phase were studied separately for the isolates. Hydrophobic nature was measured on the basis of affinity towards the xylene. Autoaggregation and coaggregation were studied on the basis of clumping of cells. In vitro adhesion studies were done on mucous which were prepared from infant child faeces. Biofilm production of superior adhesive isolate was confirmed by SEM analysis. RESULTS: Spore and vegetative phases of isolates possessed a different rate of adhesion potentials on intestinal mucous, which indicated that cell surface properties were involved in adhesion process. Spores showed a higher hydrophobicity than their vegetative cells which remained less or non hydrophobic. Vegetative phases showed capabilities for autoaggregation and coaggregation. Spores were found to be more adhesive on intestinal mucous than vegetative phase. Among enteric pathogens Vibrio cholera registered higher adhesion potentials with supporting cell surface properties. Among the five sporeforming isolates, isolate BM-3 possess superior adhesion than enteric pathogens and also exhibited biofilm formation which enhances colonization potential. CONCLUSIONS: Spore and vegetative cell phases shows differences in adhesion potentials. Cell surface properties and adhesion studies reveals that isolate BM-3 can be selected as superior isolate which is capable for biofilm production. In short, isolate BM-3 possesses an enhanced adhesion potential than enteric pathogens towards intestinal mucous which is a desirable probiotic character.