{'fraction_non_alphanumeric': 0.03322259136212625, 'fraction_numerical': 0.008305647840531562, 'mean_word_length': 5.243523316062176, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Facile Preparation of Gradient Structure Bacterial Cellulose Using Potato Starch

Membranes of bacterial cellulose (BC) produced by Gluconacetobacter xylinus combines well-known cellulose properties with the outstanding features of nanoscale materials. As a remarkable benefit of BC, the property-controlling fiber network and pore system formed by self-assembly of the cellulose molecules can be modified in situ using additives during biosynthesis. The addition of potato starch (PS) caused the double-stage morphology of the BC/PS pellicles with an opaque dense upper part and a transparent porous lower part. Moreover, as the starch content went up, the double-stage morphology of BC/PS pellicle could be easily controlled. A gradient cross-section structure could be observed through the scanning electron microscopy (SEM) as potato starch addition level increased. The BC/PS nanocomposite structure was studied using X-ray diffraction and ATR-FTIR spectroscopy, and with the introduction of gelatinized starch, the crystallinity index (CrI) of BC/PS nanocomposite reduced from 82.40 % to 72.15 %. Meanwhile, tensile strength of the freeze-dried sample reached maximum as starch content was 0.5 wt%.