In this paper, titanium dioxide nanosheets (Ti0.91O2 NSs) were incorporated into bacterial cellulose (BC) film for dielectric property tuning while maintaining the flexibility of the resulting composite paper. By taking advantage of the improved dielectric constant, the nanosheets/BC composites were employed as capacitive sensors. The fabricated devices showed the highest sensing performance of ∼2.44 × 10−3 kPa−1 from 0 to 30 N when incorporating as little as 3 vol% of Ti0.91O2 NSs (or ∼2 wt% Ti). Stable operation and high robustness of the sensor were demonstrated, where simple human motions could be efficiently monitored. This study provided a route for preparing flexible and low-cost BC composite paper for capacitive sensor. The strategy for enhancing the dielectric properties as well as sensing performances of the BC demonstrated herein will be essential for the future development of biocompatible, low-cost, and eco-friendly wearable electronics.

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Chitosan oligosaccharide (COS) is a bioactive compound derived from marine by-products. COS consumption has been demonstrated to lower the risk of diabetes. However, there are limited data on the inhibitory effect of low-molecular-weight COSs with different degrees of polymerization (DP) on α-glucosidase. This study investigates the α-glucosidase inhibitory activity of two low-molecular-weight COSs, i.e., S-TU-COS with DP2–4 and L-TU-COS with DP2–5, both of which have different molecular weight distributions. The inhibition constants of the inhibitors binding to free enzymes (Ki) and an enzyme–substrate complex (Kii) were investigated to elucidate the inhibitory mechanism of COSs with different chain lengths. The kinetic inhibition model of S-TU-COS showed non-completive inhibition results which are close to the uncompetitive inhibition results with Ki and Kii values of 3.34 mM and 2.94 mM, respectively. In contrast, L-TU-COS showed uncompetitive inhibition with a Kii value of 5.84 mM. With this behavior, the IC50 values of S-TU-COS and L-TU-COS decreased from 12.54 to 11.84 mM and 20.42 to 17.75 mM, respectively, with an increasing substrate concentration from 0.075 to 0.3 mM. This suggests that S-TU-COS is a more potent inhibitor, and the different DP of COS may cause significantly different inhibition (p < 0.05) on the α-glucosidase activity. This research may provide new insights into the production of a COS with a suitable profile for antidiabetic activity.

This research aims to reduce production capital costs and added value to natural products. The bio-mulching film was prepared by bacterial cellulose (BC) “Acetobacter xylinum”, extracted from three rotten fruits, grape, coconut, and pineapple under standard tests in the laboratory. The analysis from the FTIR technique confirmed to cellulose molecular vibration of BC films. XRD pattern was matched to structure crystallinity of JCPDS standard file which possessed a high percentage of crystallinity. The SEM micrographs were also revealed the 3D nanofiber network structure. The absorption capability of BC films could highly hold water in its structure. In addition, the mechanical properties of BC films came from rotten coconut, given the highest tensile strength (7.2 ± 1.1 MPa) according to nano-fiber symmetric with its dense structure. Nevertheless, the soil burial testing emphasized BC films could reduce soil temperature and increase moisture content in the soil as well. The biodegradation rate of BC films in 30 days was moderately fair. The BC film from rotten coconut had the slowest biodegradation rate (approximately 22.3 4.2%), applicable to biodegradable mulching film.