Effects Of Various Hydrocolloids And Surfactants On Sphere-like Bacterial Cellulose Produced By Komagataeibacter Nataicola Y19in Agitated Culture

Bacterial Cellulose is a kind of linear polymer of D-glucose in β(1-4) linkage. There are two methods to produce bacterial cellulose, one is stationary culture, which results in the accumulation of a gelatinous membrane of cellulose on the surface of the medium. The gelatinous membrane of cellulose demonstrates unique properties including high mechanical strength, high crystallinity, and high water retention ability which make it a useful material in many industries, such as food, paper manufacturing, and pharmaceutical application.The other method is agitated culture, which will form fibrous suspensions, pellets, irregular masses. Due to its bigger specific surface area and more nanoscale pores than pellicle BC, it shows great potentials as an industrial material in such as bio separation, sewage treatment, immobilization, drug delivery.In this study, various hydrocolloids and surfactants was added to Hestrin-Schramm medium and the effects of them were investigated on sphere-like BC yield, shape uniformity, and structure by Komagataeibacter nataicola Y19in agitated culture. The results show as follow.(1) The kinds of hydrocolloids, concentration of additives, confection of formation and the strains will all affect the yield and size of the sphere-like BC. For a particular hydrophilic colloid, a suitable viscosity can promote to form uniform sphere-like BC.(2)3.610g/L BC was obtained when0.1%xanthan gum was added compared with2.328g/L BC produced from the control. The uniformity of the sphere-like BC was better than the control. The resultant sphere-like BC was analyzed by using scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transforms infrared spectroscopy (FT-IR). The BC by adding0.1%xanthan gum was looser and showed more gaps and holes in the network structure, and the width of cellulose fiber with xanthan gum was broader than the control. The XRD and FT-IR results indicated that more cellulose Ip formed by adding xanthan gum, and the crystallinity and crystal size of the sphere-like BC decreased than the control.(3)3.660g/L BC was obtained when0.15%potato starch was added compared with2.328g/L BC produced from the control. The uniformity of the sphere-like BC was better than the control. The resultant of SEM shows the BC by adding0.1%xanthan gum was looser and showed more gaps and holes in the network structure, and the width of cellulose fiber with xanthan gum was broader than the control. XRD and FT-IR results indicated that more cellulose Ip (29.60%) was formed, in the meantime, it had low crystallinity (79.47%) and crystal size (3.4nm) of the sphere-like BC than the control.(4)0.05%Tween-80can enhance the yield of BC. XRD and FT-IR results indicated that more cellulose Ip (29.46%) was formed. The sphere-like had low crystallinity (78.88%) and crystal size (3.8nm) than control.(5)0.10%Trotin x-100has inhibitory effect on the yield of BC. XRD and FI-TR results show that the BC with0.10%Trotin X-100has smaller crystallinity and crystal size, and more cellulose Iβwas formed.