Effects of κ-carrageenan gum on 3D printability and rheological properties of pork pastes

The effects of κ-carrageenan gum (KG) on the 3D printability and rheological properties of pork pastes were investigated in this study. There were five groups with different levels of KG (0, 2, 4, 6, and 8 g/kg) named as KG-0, KG-2, KG-4, KG-6, and KG-8, respectively. The addition of KG increased the yield stress, viscosity, shear stress, recovery percentage, storage modulus, loss modulus, and initial and average flow forces (P < 0.05). The results of low-field nuclear magnetic resonance analysis revealed that addition of KG reduced T₂₁ and T₂₂ (P < 0.05). The best printing parameters were obtained by accuracy and stability results: printing filling percent, 90%; printing speed, 35 mm⋅s^-1; layer height, 2 mm; nozzle diameter, 1.55 mm, and KG addition level, 6 g/kg. KG addition improved the hardness, springiness, chewiness, cohesiveness, adhesiveness, and density, respectively (P < 0.05). The results suggested that KG addition improved the rheological properties and 3D printability of the pork pastes.

Improvement on gel properties of myofibrillar protein from chicken patty with potato dietary fiber: Based on the change in myofibrillar protein structure and water state

Influence of potato dietary fiber (PDF) on myofibrillar protein (MP) structure, aggregation behavior, and gel properties of chicken patty was evaluated. The Raman spectroscopy results indicated that the α-helix content decreased by 21.9 %, while β-sheets content increased by 45.0 % in 3.0 % PDF sample compared with the control (P < 0.05), and aliphatic residues cross-linked. Particle size, turbidity, and the roughness of MP surface morphology increased, whereas the zeta-potential of MPs decreased with PDF increasing. The gelation process of MP with PDF proceeded at a fast rate and their elasticity and viscosity were high as determined by dynamic rheology. Gels with 3.0 % PDF exhibited significantly enhanced gel strength and a high WHC, which increased by 44.20 % and 22.5 %, respectively, compared with the control, PDF inhibited the transformation of immobilized water to free water and eliminated the water channels during heating as well as formed a more uniform and denser microstructure. Therefore, PDF can be a potential ingredient for improving the quality of processed meat products.

Inhibition of Chitosan Ice Coating on the Quality Deterioration of Quick-Frozen Fish Balls during Repeated Freeze-Thaw Cycles

Chitosan ice coating's properties and its inhibitory effect on the quality deterioration of quick-frozen fish balls during repeated freeze-thaw cycles were investigated. When the chitosan (CH) coating concentration increased, the viscosity and ice coating rate increased, while water vapor permeability (WVP), water solubility, and transmittance decreased, and 1.5% CH was regarded as the excellent coating to apply to freeze-thaw quick-frozen fish balls. As the freeze-thaw cycles increased, the frost production, total volatile base nitrogen (TVB-N) values, and free water content of all of the samples increased significantly (p < 0.05), and the whiteness values, textural properties, and water-holding capacity (WHC) decreased. Freeze-thaw cycles expanded the aperture between the muscle fibers and the occurrence of crystallization and recrystallization between cells increased, damaging the original intact tissue structure, which were confirmed by SEM and optical microscopy. Compared with the untreated ones, the frost production, free water, and TVB-N of the samples with 1.5% CH decreased during 1, 3, 5, and 7 cycles, and were reduced by 23.80%, 32.21%, 30.33%, and 52.10% by the 7th cycle. The WHC and texture properties showed an increasing trend during the freeze-thaw cycles. Therefore, the chitosan ice coating effectively inhibited the quality deterioration by reducing water loss, the occurrence of ice crystallization and recrystallization, and the pores of the samples.

The role of mitochondrial fission in intervertebral disc degeneration

Low back pain (LBP) is an extremely common disorder and is a major cause of disability globally. Intervertebral disc degeneration (IVDD) is the main contributor to LBP. Nevertheless, the specific mechanisms underlying the pathogenesis of IVDD remain unclear. Mitochondria are highly dynamic organelles that continuously undergo fusion and fission, known as mitochondrial dynamics. Accumulating evidence has revealed that aberrantly activated mitochondrial fission leads to mitochondrial fragmentation and dysfunction, which are involved in the development and progression of IVDD. To date, research into mitochondrial dynamics in IVDD is at an early stage. The present narrative review aims to summarize the most recent findings about the role of mitochondrial fission in the pathogenesis of IVDD.

Fabrication of bilayer emulsion by ultrasonic emulsification: Effects of chitosan on the interfacial stability of emulsion

In this study, the stable system of bilayer emulsion was fabricated by ultrasonic emulsification. The effect of chitosan (CS) addition (0.05 %-0.4 %, w/v) at pH 5.0 on the stability of rice bran protein hydrolysate-ferulic acid (RBPH-FA) monolayer emulsion was investigated. It was found that the addition of CS (0.3 %) could form a stable bilayer emulsion. The droplet size was 3.38 μm and the absolute ζ-potential value was 31.52 mV. The bilayer emulsion had better storage stability, oxidation stability and environmental stabilities than the monolayer emulsion. The results of in vitro simulations revealed the bilayer emulsion was able to deliver the β-carotene to the small intestine digestive stage stably and the bioaccessibility was increased from 22.34 % to 61.36 % compared with the monolayer emulsion. The research confirmed that the bilayer emulsion prepared by ultrasonic emulsification can be used for the delivery of hydrophobic functional component β-carotene.

Analysis of inhibition of guava (Psidium guajava l.) leaf polyphenol on the protein oxidative aggregation of frozen chicken meatballs based on structural changes

This study compared the effects of guava leaf polyphenol (GLP) on the aggregation and structural changes of myofibrillar proteins (MPs) from chicken meatballs, frozen for 6 months, with that of tea polyphenol (TP). The high antioxidation ability of 450 mg/L GLP was manifested by changes in 1, 1-diphenyl-2-picrylhydrazyl (DDPH), 2, 2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity, and the ferric reducing antioxidant power (FRAP) in vitro. Compared with the control, the carbonyl, disulfide bond content, particle size, zeta potential and turbidity of sample with GLP decreased by 25.9 %, 17.7 %, 18.2 %, 11.4 % and 11.7 %, respectively, while the solubility of the sample, after freezing it for 6 months, increased by 14.8 %. Meanwhile, in sustaining the structural stability of MPs, the GLP-treated group exhibited better microstructure (scanning electron microscopy, SEM), lower free amino and sulfhydryl loss, higher α-helix structure and fluorescence intensity than the control. Our results showed that GLP significantly inhibited MP aggregation, and was superior to TP in terms of its particle size, solubility, and turbidity, sulfhydryl content (P < 0.05). Overall, it was demonstrated that GLP has the potential to inhibit protein aggregation and enhance structural stability during frozen storage.

Influence of repeated freeze-thaw treatments on the oxidation and degradation of muscle proteins from mirror carp (Cyprinus carpio L.), based on myofibrillar protein structural changes

The effects of repeated freeze-thaw (F-T) treatments on the oxidation and degradation of muscle proteins from mirror carp (Cyprinus carpio L.) were investigated. The myofibrillar fragmentation index, trichloroacetic acid-soluble peptides, total volatile basic nitrogen, amino nitrogen, and carbonyl content of the samples significantly increased (P < 0.05). However, the samples showed a significant reduction in the fragmentation index, myofibrillar protein (MP) solubility, and total sulfhydryl content after five F-T cycles (P < 0.05). Moreover, the sodium dodecyl sulfate-polyacrylamide gel electrophoresis bands of the MP faded because of the oxidation and degradation of the protein with increasing F-T cycles. By the fifth F-T cycle, the α-helix and β-turn content significantly decreased by 10.41 % and 5.72 %, respectively (P < 0.05), whereas the β-sheet and random coil content significantly rose by 7.66 % and 8.47 %, respectively (P < 0.05). Furthermore, the intrinsic fluorescence of the MP showed a substantial decrease in intensity and a redshift. In summary, iterative F-T cycles destroyed the MP structure and caused the oxidation and degradation of muscle proteins from mirror carp.

The positive contribution of ultrasound technology in muscle food key processing and its mechanism-a review

Traditional processing methods can no longer meet the demands of consumers for high-quality muscle food. As a green and non-thermal processing technology, ultrasound has the advantage of improving processing efficiency and reducing processing costs. Of these, the positive effect of power ultrasound in the processing of muscle foods is noticeable. Based on the action mechanism of ultrasound, the factors affecting the action of ultrasound are analyzed. On this basis, the effect of ultrasound technology on muscle food quality and its action mechanism and application status in processing operations (freezing-thawing, tenderization, marination, sterilization, drying, and extraction) is discussed. The transient and steady-state effects, mechanical effects, thermal effects, and chemical effects can have an impact on processing operations through complex correlations, such as improving the efficiency of mass and heat transfer. Ultrasound technology has been proven to be valuable in muscle food processing, but inappropriate ultrasound treatment can also have adverse effects on muscle foods. In the future, kinetic models are expected to be an effective tool for investigating the application effects of ultrasound in food processing. Additionally, the combination with other processing technologies can facilitate their intensive application on an industrial level to overcome the disadvantages of using ultrasound technology alone.

Testing alternative hypotheses on the origin and speciation of Hawaiian katydids

Background

Hawaiian Islands offer a unique and dynamic evolutionary theatre for studying origin and speciation as the islands themselves sequentially formed by erupting undersea volcanos, which would subsequently become dormant and extinct. Such dynamics have not been used to resolve the controversy surrounding the origin and speciation of Hawaiian katydids in the genus Banza, whose ancestor could be from either the Old-World genera Ruspolia and Euconocephalus, or the New World Neoconocephalus. To address this question, we performed a chronophylogeographic analysis of Banza species together with close relatives from the Old and New Worlds.

Results

Based on extensive dated phylogeographic analyses of two mitochondrial genes (COX1 and CYTB), we show that our data are consistent with the interpretation that extant Banza species resulted from two colonization events, both by katydids from the Old World rather than from the New World. The first event was by an ancestral lineage of Euconocephalus about 6 million years ago (mya) after the formation of Nihoa about 7.3 mya, giving rise to B. nihoa. The second colonization event was by a sister lineage of Ruspolia dubia. The dating result suggests that this ancestral lineage first colonized an older island in the Hawaiian–Emperor seamount chain before the emergence of Hawaii Islands, but colonized Kauai after its emergence in 5.8 mya. This second colonization gave rise to the rest of the Banza species in two major lineages, one on the older northwestern islands, and the other on the newer southwestern islands.

Conclusion

Chronophylogeographic analyses with well-sampled taxa proved crucial for resolving phylogeographic controversies on the origin and evolution of species colonizing a new environment.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12862-022-02037-2.

The role and mechanisms of long non-coding RNA LINC00662 in promoting the proliferation, migration, and angiogenesis of BGC-823 and HGC-27 cells and the subsequent effect on the progression of gastric cancer

A large body of evidence indicates that long non-coding ribonucleic acid (lncRNA) is widely involved in various cellular processes and tumor progression. LINC00662, an lncRNA, has been reported to play a role in lung cancer. However, the biological function of LINC00662 in gastric cancer (GC) has not yet been explored. This study aimed to investigate the role and mechanisms of LINC00662 in promoting the proliferation, migration, and angiogenesis of BGC-823 and HGC-27 cells and the subsequent effect on the progression of GC. The expression level of LINC00662 in GC tissues and cells was detected by quantitative reverse transcription polymerase chain reaction. Small interfering RNA was used to silence LINC00662 in BGC-823 and HGC-27 GC cells in vitro for an MTT assay, a colony formation assay, and a transwell assay to determine cell proliferation and invasion ability. LINC00662-silenced BGC-823 and HGC-27 cells were also injected into zebrafish to detect the proliferation and invasion ability of the cells. Co-cultures in vitro of human umbilical vein endothelial cells (HUVECs) with silenced LINC00662 and in vivo experiments were also performed. The upregulation of LINC00662 was observed in GC tissues and cell lines. Functional studies in vitro showed that knocking down LINC00662 inhibited the proliferation and invasion of GC cells. In vivo experiments in zebrafish also confirmed that knocked-down LINC00662 inhibited the proliferation and invasion of GC cells, and in vitro angiogenesis experiments showed that the supernatant of GC with knocked-down LINC00662 inhibited the angiogenesis of HUVECs. LINC00662 promoted the proliferation, invasion, and migration of GC cells and promoted angiogenesis. These findings suggest that LINC00662 may be a potential therapeutic target for GC.

Research Progress on the Preparation and Action Mechanism of Natural Deep Eutectic Solvents and Their Application in Food

Natural deep eutectic solvent (NADES) is the eutectic mixture which is formed by hydrogen bond donors (HBDs) and hydrogen bond acceptors (HBAs) with a certain molar ratio through hydrogen bonding. NADES is a liquid with low cost, easy preparation, biodegradability, sustainability and environmental friendliness at room temperature. At present, it is widely used in food, medicine and other areas. First, the composition, preparation and properties of NADES are outlined. Second, the potential mechanism of NADES in freezing preservation, the removal of heavy metals from food and the extraction of phenolic compounds, and its application in cryopreservation, food analysis and food component extraction, and as a food taste enhancer and food film, are summarized. Lastly, the potential and challenges of its application in the food field are reviewed. This review could provide a theoretical basis for the wide application of NADES in food processing and production.

Research progress on quality deterioration mechanism and control technology of frozen muscle foods

Freezing can prolong the shelf life of muscle foods and is widely used in their preservation. However, inevitable quality deterioration can occur during freezing, frozen storage, and thawing. This review explores the eating quality deterioration characteristics (color, water holding capacity, tenderness, and flavor) and mechanisms (irregular ice crystals, oxidation, and hydrolysis of lipids and proteins) of frozen muscle foods. It also summarizes and classifies the novel physical-field-assisted-freezing technologies (high-pressure, ultrasound, and electromagnetic) and bioactive antifreeze (ice nucleation proteins, antifreeze proteins, natural deep eutectic solvents, carbohydrate, polyphenol, phosphate, and protein hydrolysates), regulating the dynamic process from water to ice. Moreover, some novel thermal and nonthermal thawing technologies to resolve the loss of water and nutrients caused by traditional thawing methods were also reviewed. We concluded that the physical damage caused by ice crystals was the primary reason for the deterioration in eating quality, and these novel techniques promoted the eating quality of frozen muscle foods under proper conditions, including appropriate parameters (power, time, and intermittent mode mentioned in ultrasound-assisted techniques; pressure involved in high-pressure-assisted techniques; and field strength involved in electromagnetic-assisted techniques) and the amounts of bioactive antifreeze. To obtain better quality frozen muscle foods, more efficient technologies and substances must be developed. The synergy of novel freezing/thawing technology may be more effective than individual applications. This knowledge may help improve the eating quality of frozen muscle foods.