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Objective To explore the effects of prohibitin 2(PHB2) on sensitivity of non-small cell lung cancer cell line A549 to erlotinib (Erl) and its potential mechanisms. Methods RACK1-specific small interfering RNA was transfected in A549 cells for knocking-down of PHB2. The effects of PHB2 inhibition on cell proliferation and apoptosis induced by Erl were observed. The colocalization of microtuble-associated protein light chain 3 alpha (LC3) and mitochondria was visualized by MitoTracker staining and green fluorescent protein-microtuble-associated protein light chain 3 alpha (GFP-LC3) transfection. Cell proliferation was detected by 5-ethynyl-2′-deoxyuridine (EdU) staining. Cell colony formation was evaluated by colony forming assay. Apoptotic index of A549 cells was evaluated by TUNEL. Western blot was used to measure the expressions of PHB2 and LC3Ⅱ. Mitochondrial transmembrane potential, cytochrome c and respiratory chain complex Ⅰ/Ⅱ/Ⅴ activity were analyzed by the commercially available kits. Results Compared with the siPHB2 and siCtrl+Erl group, the EdU-positive A549 cells and the number of cell colonies decreased significantly (P＜0.05), while the TUNEL-positive A549 cells increased significantly(P＜0.05) in the siPHB2+Erl group. In addition, compared with the siPHB2 and siCtrl+Erl group, mitochondrial transmembrane potential and respiratory chain complex Ⅰ/Ⅱ/Ⅴ activity decreased significantly (all P＜0.05) and the levels of cytochrome c increased in mitochondrial fractions (P＜0.05) and decreased in cytosolic fractions(P＜0.05) in the siPHB2+Erl group. Conclusions PHB2 inhibition significantly improves sensitivity of A549 cells to Erl,which may be explained by inhibition of PHB2-mediated mitochondrial autophagy.

Bioactive ingredients such as polyphenols and carotenoids have various health benefits such as anti-cancer and antioxidant activities. However, bioactive components are unstable and easily damaged in the gastrointestinal environment, making them unable to fully exert their functional effects. Proteins and polysaccharides can form complexes via non-covalent or covalent interactions, which have been widely used as encapsulation materials to enhance the stability and activity of bioactive compounds. This review summarizes the types of protein-polysaccharide complexes, and describes the application of the anti-solvent, pH-driven, thermal gelation and emulsification methods for the delivery of bioactive ingredients by protein-polysaccharide complexes. It is anticipated that this review will provide a reference for the research and application of bioactive compounds encapsulated in protein-polysaccharide complexes.

In this study, a composite hydrogel system was constructed by cross-linking of primary network hydrogels of gelatin (GE) and sodium hexametaphosphate (SHMP) by transglutaminase (TGase) after addition of Lactobacillus plantarum in order to improve its viability and bioavailability. The experimental results showed that the modification by SHMP and TGase changed the gel strength, water distribution state, and gel network structure of gelatin, and reduced the gelation rate, so that the three-dimensional network structure of the gel was more stable, and the intermolecular forces of the composite hydrogel was stronger, contributing to the resistance of the encapsulated L. plantarum to adverse environments. The presence of L. plantarum was found to slightly disrupt the ordered structure of the hydrogel by scanning electron microscopy (SEM). Endogenous fluorescence spectroscopy analysis showed that addition of L. plantarum resulted in the exposure of the extended region containing tryptophan within the GE molecule to a more polar environment. The steric effect occurred during the gelling process, delaying the formation of covalent crosslinks and physical interactions between the biopolymer molecules, which led to changes in their microstructure. Simulated gastrointestinal digestion tests and storage tests showed that L. plantarum encapsulated in GE/SHMP/TGase gels had better survival rates and gastrointestinal release properties compared to single GE-based hydrogels. It was confirmed that GE/SHMP/TGase hydrogels had a better protective effect on L. plantarum. In conclusion, this study has explored a new method for preparing GE-based hydrogels as a delivery system for probiotics, which will provide a theoretical basis for the development of probiotic functional foods.

Summary: The current work was carried out to enhance the quality (including product colour, rehydration performance, textural properties, product cracking rate and sensory evaluation) of microwave freeze‐dried prepared taro balls, a popular starch‐based food product, by synergistic addition of guar gum and sodium bicarbonate. The results showed that taro balls with added sodium bicarbonate had the shortest freeze‐drying time (153 min), but the high‐cracking rate (66.67%) was not acceptable to consumers. The addition of guar gum could effectively reduce the cracking rate (17.5%) during freeze‐drying of taro balls, but did not significantly improve sensory evaluation and textural properties. The combination of sodium bicarbonate and guar gum demonstrated satisfactory positive effects in increasing the rehydration rate of freeze‐dried taro balls (53.67%), maintaining the whiteness (WI = 84.52) and reducing the cracking rate (21.67%). Although sodium bicarbonate alone produced the best results in terms of sensory ratings and textural properties, there was no significant difference between the effects of sodium bicarbonate alone and the combination of the two food additives on rehydrated taro balls. Therefore, the combination of sodium bicarbonate and guar gum is an appropriate hybrid strategy for producing high quality freeze‐dried taro balls. [ABSTRACT FROM AUTHOR]