Integrated Omics Approach: Revealing the Mechanism of Auxenochlorella pyrenoidosa Protein Extract Replacing Fetal Bovine Serum for Fish Muscle Cell Culture.

The process of producing cell-cultured meat involves utilizing a significant amount of culture medium, including fetal bovine serum (FBS), which represents a considerable portion of production expense while also raising environmental and safety concerns. This study demonstrated that supplementation with Auxenochlorella pyrenoidosa protein extract (APE) under low-serum conditions substantially increased Carassius auratus muscle (CAM) cell proliferation and heightened the expression of Myf5 compared to the absence of APE. An integrated intracellular metabolomics and proteomics analysis revealed a total of 13 and 67 differentially expressed metabolites and proteins, respectively, after supplementation with APE in the medium containing 5%FBS, modulating specific metabolism and signaling pathways, which explained the application of APE for passage cell culture under low-serum conditions. Further analysis revealed that the bioactive factors in the APE were protein components. Moreover, CAM cells cultured in reconstructed serum-free media containing APE, l-ascorbic acid, insulin, transferrin, selenium, and ethanolamine exhibited significantly accelerated growth in a scale-up culture. These findings suggest a promising alternative to FBS for fish muscle cell culture that can help reduce production costs and environmental impact in the production of cultured meat.

Investigating the loss of major yolk proteins during the processing of sea cucumber (Apostichopus japonicus) using an MRM-based targeted proteomics strategy.

Major yolk proteins (MYPs), one class of the main abundant proteins in sea cucumber body wall, seem to garner more attention in recent years. Herein, a method using multiple reactions monitoring mass spectrometry (MRM-MS) was deliberatively developed to perform quantification analysis of three MYPs, i.e. BAH79576.1, BAH79577.1 and PIK45784.1. Contents of MYPs in body wall of fresh and dried sea cucumbers as well as in waste liquid of boiling and steaming were determined using their corresponding signature peptides of VDEFTGIVGSLR, KLDMYPPPLAR, LDMYPPPLAR, and SGHGEVMFVDSK. The loss of MYPs in the processing of sea cucumbers was directly verified by quantitation data of MYPs in sea cucumber body wall and the waste liquids. This study not only evidenced the loss of MYPs during the processing of sea cucumbers, but also implicated the potential of recycling MYPs from the processing waste water, providing helpful suggestions in maximizing the value of sea cucumbers.

Differentiation of three commercial tuna species through Q-Exactive Orbitrap mass spectrometry based lipidomics and chemometrics.

Mislabeling and adulteration of tuna are common due to the diminishing of morphological characteristics during processing. The tuna authenticity is now being focused in the seafood supply chain. In this study, the lipid profiles of 3 commercial tuna species (skipjack tuna, bigeye tuna and yellowfin tuna) were investigated via ultra-high performance liquid chromatography coupled with Q-Exactive Orbitrap mass spectrometry (UPLC-Q-Exactive Orbitrap MS). A total of 439 lipid species were identified and semi-quantitated by MS-DIAL. Further biomarkers discovery was carried out by chemometrics, leading to 27 lipids being identified as potential lipid biomarkers. Comparisons to reference standards revealed that lipid biomarkers were effective for discrimination of different tuna species. Interestingly, the proposed lipid biomarkers were all glycerophospholipids, implying that they might be the focus of future study.

Uncovering proteome variations of differently heat-treated sea cucumber (Apostichopus japonicus) by label-free mass spectrometry.

The effects of heat treatment on the proteome of Apostichopus japonicus have been evaluated using label-free quantitative proteomics by ultrahigh performance liquid chromatography-quadrupole/time of flight (UHPLC-Q/TOF) mass spectrometry with sequential window acquisition of all the theoretical fragment ion (SWATH) acquisition mode. Chemometric tools are integrated to reveal proteomic changes by mining the protein quantitation data from fresh and differently heat-treated samples. SWATH allows the quantitation of 548 proteins, of which 24 proteins are significantly sensitive to heat treatment and 13 proteins vary significantly responding to different heat procedures (boiling, steaming, and microwave heating), and 5 of them are sharing proteins. Gene ontology (GO) annotation of the differentiating proteins highlights most of them are relevant to molecular functions. The results can be favorable to evaluate the effects of heat treatment on the nutrition and function of processed sea cucumbers and facilitate the selection of an optimal thermal treatment.

Effects on Surface and Physicochemical Properties of Dielectric Barrier Discharge Plasma-Treated Whey Protein Concentrate/Wheat Cross-Linked Starch Composite Film.

Dielectric barrier discharge (DBD) plasma is a new type of polymer surface modification technology. This study is mainly about the changes in film surface structure and physicochemical properties of whey protein concentrate (WPC)/wheat cross-linked starch (WCS) composite films after DBD plasma treatment with different plasma parameters. The results show that the proper plasma treatment parameters (400 W to 60 s) can increase the surface roughness, tensile strength, barrier properties, and thermal stability of the edible film and decrease elongation at break and the water contact angle. X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and X-ray diffraction showed that DBD plasma treatment could increase the content of oxygen-containing groups on the WPC/WCS film surfaces instead of damaging the internal crystal structure. The results showed that use of proper DBD plasma treatment technology has a positive effect on the mechanical and barrier properties and thermal stability of WPC/WCS films. PRACTICAL APPLICATION: DBD plasma treatment can improve the mechanical, barrier, and thermal properties of WPC/WCS films without generating any pollution. The DBD plasma can be potentially applied in the enhancement of edible film properties. WPC/WCS films are more environmentally friendly than plastics and can be a replacement for traditional plastics.

Acetylated Distarch Phosphate/Chitosan Films Reinforced with Sodium Laurate-Modified Nano-TiO2 : Effects of Sodium Laurate Concentration.

Nano-titanium dioxide (TiO2 ) was modified with the surfactant sodium laurate (SL) via ultrasonic microwave-assisted technology to improve the dispersion of TiO2 in polymer matrices. As revealed by Fourier transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy analyses, SL was well adsorbed onto the TiO2 surface through chemical bonding, resulting in SL-modified TiO2 (TiO2 -SLx). The hydrophobicity and dispersibility of TiO2 -SLx increased significantly compared to unmodified nano-TiO2 . With an increase in the SL concentration from 5% to 15%, the agglomeration of TiO2 -SLx particles decreased considerably, while the particles were more uniform. TiO2 -SLx nanoparticles (3 wt%) were then incorporated into acetylated distarch phosphate/chitosan (ADPS/CS) blended matrices to reinforce the biopolymers. Relative to unmodified TiO2 , TiO2 -SLx exhibited a better dispersion capability. Furthermore, as the SL concentration increased, the tensile strength (TS) of the composite films increased, while the elongation at break (E), water vapor permeability (WVP), and solubility all decreased. The composite film containing TiO2 -SL15 (TiO2 modified with 15% SL; ADPS/CS-TiO2 -SL15 film) displayed the highest TS (31.50 MPa), which was 33.70% higher than that of the pure ADPS/CS film, whereas the ADPS/CS-TiO2 -SL25 film exhibited the lowest E. Further, the ADPS/CS-TiO2 -SL15 film displayed the lowest WVP (0.90 × 10-12 g·cm-1 ·s-1 ·Pa-1 ) and solubility (22.91%), which decreased by 30.23% and 26.03% compared to that of the pure ADPS/CS film, respectively. Therefore, SL modification and the use of ultrasonic microwave-assisted technology are promising for the preparation of nanofillers for biopolymer reinforcement. PRACTICAL APPLICATION: Nano-titanium dioxide (TiO2 ) nanoparticles were modified using the anionic surfactant sodium laurate via ultrasonic-microwave assisted technology, to improve the dispersion of the TiO2 nanoparticles in polymer matrices. Modified TiO2 nanoparticles were incorporated into acetylated di-starch phosphate/Chitosan blend films, causing the tensile strength of the composite film to increase and the water solubility and water vapor permeability of the composite film to decrease, making the films suitable for packaging applications.