The cellulosic part of rice straw was modified to develop N-halamine 11 derivatives for disinfection. The process involved cross-linking of the cellulosic material 12 with amino/amide/imide containing compounds; cyclic and acyclic. The structures of the 13 prepared materials were identified using FTIR and solid state 13 CNMR. The modified 14 materials were halogenated to form N-halamines and the antimicrobial activity of each 15 evaluated against examples of Gram-positive (Staphylococcus aureus) and Gram-16 negative bacteria (Escherichia coli) using a variety of methods; agar plate, blended agar, 17 stirred flask and in columns. One of the N-halamines achieved a 9 log reduction against 18 both E. coli and S. aureus in 4 hours. In addition, no S. aureus growth was recorded on 19 agar plates blended with 0.5g of this same material. 20

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An N-Halamine biocidal polymer was prepared by co-polymerizing toluene-2,6-diisocyanate with a new heterocyclic uramil-based azo-monomer, followed by halogenation. The mode of action of N-halamine polymers on bacteria was investigated and halogenation conditions (temperature, halogenation time, halogen concentration) were optimized for bactericidal action against E. coli and S. aureus. It was found that the mode of action of this type of polymer is a combination of different factors; contact, release, and through interaction of the polymer with the bacterial medium. The most effective halogenation conditions were stirring 1 g polymer in 10 mL sodium hypochlorite (10 %) for 1 h at ambient temperature (22 C).

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Mutation and selection for increased resistance to cell-wall synthesis inhibitors led to alterations in the hyphal branching rate of Saccharopolyspora erythraea NRRL 2338. Mutants with decreased branching frequency exhibited increased hyphal strength (estimated by in vitro micromanipulation). As the hyphal strength was increased, this led to a greater proportion of hyphal particles in liquid culture with a hyphal fragment diameter of greater than 88 microm. This, in turn, coincided with proportionately increased antibiotic production.