Silver Nanoparticles Impregnated Biocellulose Produced by Sweet Glutinous Rice Fermentation with the Genus Acetobacter

Division of Environmental Sciences and Natural Resources, Faculty of Science and Technology, Rajamangala University of Technology Phra Nakhon, Bangkok, Thailand

^* Corresponding author: duongruitai.n@rmutp.ac.th

Abstract

Bacterial cellulose (BC) is a natural renewable and biodegradable polymer and mostly synthesized from the bacteria genus, Acetobacter. More recent studies on effective biopolymer in various applications have been conducted due to its uniform structure and morphology superior to those of plant cellulose. In this study, the researchers have observed the effectiveness on antimicrobial activity of BC produced by sweet glutinous rice as a raw material instead of cellulosic materials. In the process, sweet glutinous rice fermented by Loog-pang was fermented for alcohol before further making rice vinegar product by inoculating with Gluconacetobacter xylinum TISTR 086, or mixed with indigenous vinegar producers, isolated Acetobacter spp. from our laboratory. Both these two samples gave comparable BC yields and the antimicrobial activity after impregnating with silver nanoparticles and also comparable to the control coconut vinegar medium (2.20 vs 2.00 g/L within 3 days). The optimum conditions for high BC production were pH 4 to 7, temperature approximately 25-30°C, slow agitation (50 to 90 rpm) as well as static cultivation. The remarkable antimicrobial activities of silver nanoparticles impregnated BC products (Ag-BC) showed high tentative in vitro inhibition on common pathogens in contaminated wounds; Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa by agar diffusion test. From this study, Ag-BC produced by fermented sweet glutinous rice (FSR) will therefore be one attractive affordable choice for being biomaterials applied in medical interests, especially skin disinfectant.