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The present study aimed to develop a new bio-nanocomposite film based on gum arabic (GA) reinforced with cellulose nanocrystals (CNC). CNC was successfully fabricated and its microstructure was characterized. Subsequently, the effects of CNC on the rheological, physicochemical and functional properties of GA-based films were systematically evaluated. Results showed that the tensile strength (2.21 MPa) and elongation at break (62.79%) of film incorporated with 4% (w/w) CNC were effectively increased compared with the GA film (1.08 MPa and 42.50%). Additionally, 4% CNC reduced the water vapor and oxygen permeability by 10.61% and 25.30% respectively, while improved the ultraviolet light barrier and thermal stability of film. The well dispersion and filling effect of nanofiller contributed to form a compact and homogeneous film structure. Furthermore, the film containing 4% CNC decreased the weight loss of strawberries by 23.80% compared with the control group, thus delaying the deterioration of strawberry quality during storage.

This study aimed to evaluate the effects of cellulose nanocrystals (CNC) on the basic properties of soy protein isolate films, and especially to propose the corresponding formation mechanism. Tensile strength, barrier properties, and water resistance were effectively improved after the formation of nanocomposite films. Incorporating CNC could restrict water mobility and improve the viscoelastic properties of films. Appropriate content of CNC (0.50% and 0.75%) promoted the construction of a more homogeneous and compact film structure, which may be attributed to the CNC-induced conformational modifications and the enhanced hydrophobic and hydrogen-bond interactions. While excessive CNC (1.00%) was not conducive to the integrity and continuity of film structures, resulting in the weakened functional properties. The obtained films were able to decrease total viable counts and total volatile basic nitrogen of stored pork, and extend the shelf-life of strawberry. This work offers a theoretical basis for the application of CNC in packaging industry.

The active food packaging films prepared in this study used gum arabic (GA)-cellulose nanocrystals (CNC) as the film-forming matrix, and grape skin extract (GSE), pomegranate peel extract (PPE) and red pitaya peel extract (RPPE) as natural antioxidants by solution casting method. The combination of extracts changed the color and microstructure of the films, resulting in a decrease in mechanical strength and water resistance, but their flexibility and light transmittance were improved. Particularly, the PPE film can almost completely block the passage of ultraviolet light (200–400 nm). In addition, the composite films carrying the extracts possessed antioxidant capacity, which can extend the storage period of raspberries. The PPE film with the highest activity prominently reduced total color difference (4.08–2.08), weight loss rate (19.71–5.81%), moisture evaporation (21.29–18.22%) and fluctuation of nutrient content of the fruits in the raspberry preservation test.

Cervical cancer is the second most common type of cancer among women worldwide and a leading cause of mortality in women. Metastases reduce the overall survival rate in patients with cervical cancer. Thus, it is clinically urgent to investigate the molecular mechanism of cervical cancer metastasis. The aim of the present study was to investigate the mechanism of microRNA (miR)‑378 in the metastasis of cervical cancer. In the present study, miR‑378 expression levels were significantly upregulated in cervical cancer tissues and cervical intraepithelial neoplasia III tissues when compared with normal cervix tissues. Re‑expression of miR‑378 significantly promoted tumor migration and invasion in vitro, and metastasis in vivo, while downregulation of miR‑378 suppressed the effect in vitro. Luciferase reporter assay revealed that autophagy‑related protein 12 (ATG12) was a direct target of miR‑378 and its expression was downregulated by miR‑378. In cervical cancer tissues with lymph node metastasis, miR‑378 was upregulated while ATG12 was downregulated when compared with lymph node negative cases. To the best of our knowledge, the present study is the first to provide evidence that miR‑378 may be associated with ATG12. Collectively, the data of the present study suggested that miR‑378 may function as an oncogene by promoting metastasis in cervical cancer. The finding that miR‑378 targets ATG12 indicated that miR‑378 may have a potential role in autophagy. These findings may provide novel insights into the mechanism of metastasis in cervical cancer and a novel therapeutic target for the treatment of cervical cancer.

Spherical curcumin/polyvinylpyrrolidone nanocapsules (CurNC) with the improved water solubility and thermal stability than native curcumin (Cur) were synthesized. Subsequently, soy protein isolate-based pH-sensitive multifunctional packaging films reinforced with cellulose nanocrystals (CNC), CurNC, CNC/CurNC, and CNC/Cur were developed for shrimp freshness detection. It was found that adding the CNC-containing agents improved the tensile strength, hydrogen bond interactions, thermal stability, and crystalline structure of the film and decreased its water solubility and water vapor and oxygen permeability. The Cur-containing agents decreased the L* (lightness/darkness) and a* (redness/greenness) values and increased the b* (yellowness/blueness) and ΔE (total color difference) values of the film. A more dense and uniform matrix of the nanocomposite films was likely responsible for delaying the release of Cur from the film matrix. Interestingly, CNC/CurNC film displayed higher antiradical scavenging activity than CNC/Cur film, as well as remarkable color responsiveness to pH changes and NH3 presence. Moreover, the CNC/CurNC film was able to decrease the total volatile basic nitrogen of stored shrimp and visually monitor shrimp freshness in real-time.

For effectively improving the physical defoaming efficiency in foam fractionation, a new foam breaker with synthetic sponge cylinders was developed and its defoaming mechanism was analyzed. Due to synthetic sponge’s high water absorption ability, it resulted in a large pressure difference inside and outside the liquid film to rapidly collapse the foam. The defoaming efficiency was studied on the basis of the effects of the type and number of synthetic sponge cylinders, SDS concentration, volumetric liquid fraction and volumetric air flowrate. The results show that the synthetic sponge cylinder with 0.23 ± 0.05 mm in mean pore diameter and 70.0 ± 0.5% in mean porosity had the highest defaoming efficiency and a larger number of synthetic sponge cylinders resulted in a higher defoaming percentage. Under suitable conditions, defoaming percentage of the new foam breaker with 4 of the optimal synthetic sponge cylinders reached 100.0%. Furthermore, the synthetic sponge cylinders had much higher defoaming efficiency, lower equipment cost, lower energy consumption and simpler preparation than perforated plates and paddle agitator. So the foam breaker with synthetic sponge cylinders is highly promising in industrial defoaming.

Foam fractionation and resin adsorption were used to recover soybean saponins from the industrial residue of soybean meal. First, a two-stage foam fractionation technology was studied for concentrating soybean saponins from the leaching liquor. Subsequently, resin adsorption was used to purify soybean saponins from the foamate in foam fractionation. The results showed that the enrichment ratio, the recovery percentage, and the purity of soybean saponins by using the two-stage foam fractionation technology could reach 4.45, 74%, and 67%, respectively. After resin adsorption and desorption, the purity of soybean saponins in the freeze-dried powder from the desorption solution was 88.4%.

This study aimed to evaluate the effect of calcium ions (Ca2+) on the thermal gelling properties of cellulose nanocrystals-whey protein isolate composite gels, as well as to propose a corresponding ion-induced gelation mechanism. It was found that the gel strength, viscoelasticity, and thermal stability of the mixed gels gradually improved with an increase in the Ca2+ concentration from 0 M to 0.15 M. The addition of an appropriate Ca2+ could induce the conformational transformation from α-helix to β-sheet, increase the content of tryptophan residues and reactive sulfhydryl groups, and enhance the hydrophobic interactions and the amide II band, which promoted the full unfolding and orderly aggregation of protein molecules to form a stable three-dimensional gel network. However, 0.20 M Ca2+ resulted in the formation of a coarse gel structure with some irregular aggregates, thereby leading to the decreased water holding capacity and gel strength. This research offers a theoretical foundation for the design and development of novel composite food gels with various functional properties.

This study aimed to develop soy protein isolate (SPI)-based active nanocomposite films reinforced with cellulose nanocrystals (CNC), zinc oxide nanoparticles (ZnONP), CNC/ZnONP mixture (physical mixing), or CNC@ZnONP nanohybrids (in situ growth). The tensile strength, oxygen and water vapor barrier properties, water resistance ability, and thermal stability were substantially improved by the incorporation of nano reinforcements, particularly the CNC-containing agents. However, the nanocomposite films displayed a lower elongation at break, surface hydrophobicity, and transmittance compared with the pure SPI-based film. The filling effect of reinforcements and their hydrogen bonds with the film matrix contributed to the formation of a compact and homogeneous film structure. The ZnO-containing films obviously inhibited the growth of foodborne pathogens (Escherichia coli and Staphylococcus aureus) and also reduced the total viable counts and the total volatile basic nitrogen values in a pork sample. Furthermore, the CNC@ZnONP film prevented the migration of zinc from the film into the food system. Therefore, the obtained nanocomposite films have broad application prospects in the field of active food packaging.