In this study, carboxymethyl cellulose (CMC) films containing 1%, 2%, and 3% Chinese fir essential oil (CFEO) were prepared. The mechanical, optical, physical, microstructural, thermal stability and antimicrobial properties of the films were studied. A traditional steam distillation method was applied for CFEO extraction, in which 35 volatile components were identified. The research results showed that the CMC film mixed with 1% CFEO had the highest tensile strength (TS) and elongation at break (EB), whereas the flexibility was decreased under higher concentrations of CFEO. However, the film’s degree of transparency under controlled humidity did not decrease with an increase in CFEO concentration; thus, the sensory evaluation was not adversely effect. Furthermore, the thickness and the water solubility (WS) of film increased after the addition of CFEO. The thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) results indicated that the thermal stability of the CMC-CFEO films improved. Moreover, the composite films showed excellent inhibitory effects toward Gram-positive bacterias and Penicillium citrinum. The treatments of grapes with CMC + 1% CFEO resulted in the best properties during storage. CMC-CFEO film can be a candidate for food packaging due to its excellent performances.

A novel strain, designated WH2-56, was isolated from a slime sample collected from a paper company along the Yangtze River during March, 2018. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain WH2-56 was related to members of the genus Planomicrobium. Cellulolytic activity of the sample was screened and confirmed by Congo red-polysaccharide interactions and examined by broth culture using filter paper (FP) with no starch as the sole carbon source. Field emission scanning electron microscopy (FE-SEM) was used to confirm the delicate morphological changes of FP during bio-degradation. Different cellulosic materials were used to measure biodegradation effects and optimum incubation conditions. The activity of FPase and carboxymethyl cellulase (CMCase) were checked by 3,5-dinitrosalicylic acid (DNS agents) with different carbon sources, which showed a peak at 0.62 U/mL of CMCase on day 4, and at 0.38 U/mL of FPase on day 5.

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