Variations in fungal and bacterial microbiome and chemical composition among fermenting Kishu-Narezushi batches.

Kishu-Narezushi is a spontaneously fermented food comprising fish, rice, and salt. During spontaneous fermentation, the microbiome may differ among batches, even when manufactured in the same way. In addition, analyses of changes in the chemical composition of the product are important for clarifying flavor characteristics. We collected basic information on the microbiome and chemical composition of Kishu-Narezushi using multiple batches of fermentation and evaluated whether the microbiome was homogeneous. The fungal microbiome of Kishu-Narezushi was dominated by Saccharomycetales and Trichosporonales. The bacterial microbiome was diverse, although seven specific genera of lactic acid bacteria were identified. Glutamic acid, histidine, and serine levels decreased after ∼10 days of fermentation. Succinic acid, characteristic of Kishu-Narezushi, accumulated upon the consumption of glutamic acid. Though the microbiome was diverse, the chemical composition was similar among the batches.

Amylose-grafted Curdlan: A New Class of Semi-artificial Branched Polysaccharides for Hierarchical Polymeric Superstructures Created by the Action of "Orthogonal" Binding Sites.

The semi-artificial branched-polysaccharides, amylose-grafted curdlans, were synthesized utilizing an enzymatic polymerization. Both a curdlan main chain and amylose side chains on the polysaccharides maintain the original helical structure as well as the molecular binding ability. Thanks to the difference in their molecular recognition properties between ß-1,3-glucan chain and α-1,4-glucan chain, the amylose-grafted curdlans can provide two different orthogonal binding sites within one polymeric system. When a water-soluble polythiophene was mixed with the amylose-grafted curdlan, the polythiophene was twisted in two different modes and therein, fluorescence energy of the polythiophene wrapped by the amylose side chains was successfully transferred to the polythiophene wrapped by the curdlan main chain. We thus concluded that in the dendritic superstructure of this polysaccharide, a self-organized "Janus-type FRET system" was successfully constructed.