Fresh oil palm frond juice as a novel and alternative fermentation medium for bacterial cellulose production

In this study, fresh oil palm frond (OPF) juice was explored as an alternative fermentation medium for the production of bacterial cellulose (BC) by Acetobacter xylinum 0416. The effect of surface area to volume of fermentation medium (S/V) ratio and nitrogen sources supplementation to OPF juice were investigated to improve the BC production. The S/V ratio of 0.25, 0.50 and 0.75 were initially prepared using Hestrin and Schramm (HS) medium. The medium was inoculated with A. xylinum 0416 and incubated statically at 28 +/- 1 degrees C for 10 days. The yield and properties of BC produced were measured where the highest yield and best properties obtained reflects the optimum S/V ratio. The production of BC from supplemented OPF juice with yeast extract and peptone were carried out at the same fermentation condition and optimum S/V ratio. The thickness and yield of BC obtained were measured while its characteristics were analysed using scanning electron microscopy (SEM), X-ray diffraction (XRD) and tensile strength. Results showed that the lowest S/V ratio at 0.25 gave the highest yield of BC, superior crystallinity and tensile strength as compared to the higher S/V ratio. SEM images of BC samples exhibited a slight difference on the surface morphology of BC network between the three S/V ratios, whilst denser BC network was obtained from OPF juice. The production of BC from OPF juice showed outstanding performance by increasing the yield up to six times higher to that produced in HS medium. Moreover, the BC exhibited superior tensile strength and crystallinity compared to the BC produced from HS medium. Therefore, the findings from this study offer a promising alternative fermentation feedstock from OPF juice for BC production. (C) 2019 Elsevier Ltd. All rights reserved.