To improve the color stability of anthocyanins (ACNs) in blueberry fermented beverage, the intermolecular copigmentation between ACNs and 3 different phenolic compounds, including (-)-epigallocatechin gallate (EGCG), ferulic acid (FA), and gallic acid (GA) as copigments, was compared in the model and the real blueberry fermented beverage, respectively. The copigmented ACNs by EGCG presented a high absorbance (0.34 a.u.) and redness (27.09 ± 0.17) in the model blueberry fermented beverage. The copigmentation by the participation of the 3 different phenolic compounds showed all a spontaneous exothermic reaction, and the Gibbs free energy (ΔG°) of the system was lowest (-5.90 kJ/mol) using EGCG as copigment. Furthermore, the molecular docking model verified that binary complexes formed between ACNs and copigments by hydrogen bonds and π-π stacking. There was a high absorbance (1.02 a.u.), percentage polymeric color (PC%, 68.3 %), and good color saturation (C*ab, 43.28) in the real blueberry fermented beverage aged for 90 days, and more malvidin-3-O-glucoside had been preserved in the wine using EGCG as copigment. This finding may guide future industrial production of blueberry fermented beverage with improved color.

An ischemic stroke, one of the leading causes of morbidity and mortality, is caused by ischemia and hemorrhage resulting in impeded blood supply to the brain. According to many studies, blueberries have been shown to have a therapeutic effect in a variety of diseases. Therefore, in this study, we investigated whether blueberry-treated mesenchymal stem cell (MSC)-derived extracellular vesicles (B-EVs) have therapeutic effects in in vitro and in vivo stroke models. We isolated the extracellular vesicles using cryo-TEM and characterized the particles and concentrations using NTA. MSC-derived extracellular vesicles (A-EVs) and B-EVs were round with a lipid bilayer structure and a diameter of ~150 nm. In addition, A-EVs and B-EVs were shown to affect angiogenesis, cell cycle, differentiation, DNA repair, inflammation, and neurogenesis following KEGG pathway and GO analyses. We investigated the protective effects of A-EVs and B-EVs against neuronal cell death in oxygen-glucose deprivation (OGD) cells and a middle cerebral artery occlusion (MCAo) animal model. The results showed that the cell viability was increased with EV treatment in HT22 cells. In the animal, the size of the cerebral infarction was decreased, and the behavioral assessment was improved with EV injections. The levels of NeuN and neurofilament heavy chain (NFH)-positive cells were also increased with EV treatment yet decreased in the MCAo group. In addition, the number of apoptotic cells was decreased with EV treatment compared with ischemic animals following TUNEL and Bax/Bcl-2 staining. These data suggested that EVs, especially B-EVs, had a therapeutic effect and could reduce apoptotic cell death after ischemic injury.

BACKGROUND: The viral main protease (Mpro) of SARS-CoV-2 has been recently proposed as a key target to inhibit virus replication in the host. Therefore, molecules that can bind the catalytic site of Mpro could be considered as potential drug candidates in the treatment of SARS-CoV-2 infections. Here we proposed the application of a state-of-the-art analytical platform which combines metabolomics and protein structure analysis to fish-out potential active compounds deriving from a natural matrix, i.e., a blueberry extract.
METHODS: The experiments focus on finding MS covalent inhibitors of Mpro that contain in their structure a catechol/pyrogallol moiety capable of binding to the nucleophilic amino acids of the enzyme\'s catalytic site.
RESULTS: Among the potential candidates identified, the delphinidin-3-glucoside showed the most promising results. Its antiviral activity has been confirmed in vitro on Vero E6 cells infected with SARS-CoV-2, showing a dose-dependent inhibitory effect almost comparable to the known Mpro inhibitor baicalin. The interaction of delphinidin-3-glucoside with the Mpro pocket observed was also evaluated by computational studies.
CONCLUSIONS: The HRMS analytical platform described proved to be effective in identifying compounds that covalently bind Mpro and are active in the inhibition of SARS-CoV-2 replication, such as delphinidin-3-glucoside.

To enhance the stability of anthocyanins under conditions such as light, temperature, and pH, an apricot polysaccharide hydrogel for anthocyanins encapsulation was prepared in this study. Apricot polysaccharides with different DEs were prepared by an alkaline de-esterification method. A gel was prepared by mixing the apricot polysaccharides with CaCl2 to encapsulate the anthocyanins; the encapsulation efficiency reached 69.52 ± 0.31 %. Additionally, the gel exhibited favorable hardness (144.17 ± 2.33 g) and chewiness (64.13 ± 1.53 g). Fourier transform infrared (FTIR) and X-ray diffractometer (XRD) spectra confirmed that the formation of the hydrogel primarily relied on electrostatic interactions and hydrogen bonding. Compared with free anthocyanins, it was also found that the gel-encapsulated anthocyanins had a higher retention rate (RR) under different temperatures and light.

While spot spraying has gained increasing popularity in recent years, spot application of granule agrochemical has seen little development. Despite the potential for the technology, there currently exists no commercially available granular applicators capable of spot application. Therefore, the goal of this study was to design, build, and lab evaluate a precision applicator for spot applying granular agrochemical in wild blueberry. The design incorporated a John Deere RC2000 with a custom control box, recirculation system, and electrically actuated valves. All components were modified to fit a Valmar 1255 Twin-Roller. The system receives inputs from a predeveloped prescription map and can actuate each of the twelve valves separately to provide individual orifice control. Casoron® G4 was used as the testing agrochemical and in cycling the product pneumatically for 1 hour incurred no significant product degradation (p = 0.110). In lab evaluations, the applicator encountered zero errors in reading prescription maps and actuating the correct valves accordingly. Further, the granule recycling system had zero instances where product built up in the lines or jammed the valves. In all, this project represents the first successful development of a precision granular spot applicator for any cropping system.

The aim of this study was to prepare active intelligent gluten protein films using wheat gluten protein (WG) and apple pectin (AP) as film-forming matrices, and blueberry anthocyanin extract (BAE) as a natural indicator. SEM and FT-IR analyses demonstrated the successful immobilization of BAE in the film matrix by hydrogen bonding interactions and its compatibility with WG and AP. The resultant WG-AP/BAE indicator films demonstrated notable antioxidant activity, color stability, barrier qualities, pH and ammonia response sensitivity, and mechanical properties. Among them, WG-AP/BAE5 exhibited the best mechanical properties (TS: 0.83 MPa and EB: 242.23%) as well as the lowest WVP (3.92 × 10-8 g.m/m2.Pa.s), and displayed high sensitivity to volatile ammonia. In addition, WG-AP/BAE5 showed a color shift from purplish red to green to yellowish green, demonstrating the monitoring of shrimp freshness in real time. Consequently, this study offers a firm scientific foundation for the development of active intelligent gluten protein films and their use in food freshness assessments.

Molecular hydrogen is beneficial for fruits quality improvement. However, the mechanism involved, especially cellular metabolic responses, has not been well established. Here, the integrated widely targeted metabolomics analysis (UPLC-MS/MS) and biochemical evidence revealed that hydrogen-based irrigation could orchestrate, either directly or indirectly, an array of physiological responses in blueberry (Vaccinium spp.) during harvesting stage, especially for the delayed senescence in harvested stage (4 °C for 12 d). The hubs to these changes are wide-ranging metabolic reprogramming and antioxidant machinery. A total of 1208 distinct annotated metabolites were identified, and the characterization of differential accumulated metabolites (DAMs) revealed that the reprogramming, particularly, involves phenolic acids and flavonoids accumulation. These changes were positively matched with the transcriptional profiles of representative genes for their synthesis during the growth stage. Together, our findings open a new window for development of hydrogen-based agriculture that increases the shelf-life of fruits in a smart and sustainable manner.

A dynamic compressed fluid-based separation process combining carbon dioxide and ethanol was explored to isolate portisins previously hemi-synthesized from blueberry surplus anthocyanins. The influence of process parameters such as pressure (100-500 bar), temperature (40-60 °C), and ethanol content in the compressed fluid mixture (20-50 wt%) on extraction yield, portisins yield, and portisins content in the extract was investigated. The two-step isolation process includes (1) a first step at 100 bar, 60 °C, and 20 wt% ethanol content in the compressed fluid mixture to remove the low polarity compounds; and (2) a second step at 500 bar, 40 °C, and 100 wt% ethanol to recover portisins, resulting in a 1.5-fold increase in portisins content. The performance of the two-step separation process was compared to centrifugal partitional chromatography and conventional reverse phase liquid chromatography already reported in terms of portisins content in the extract, process throughput, process efficiency, and total solvent used. The two-step separation process decreased the total solvent used, although with a decrease in the throughput and efficiency. Nevertheless, the choice of the best separation technology depends on the application, as these techniques result in different portisins purities. Overall, this study contributed to a scalable and more sustainable process for natural colorant production, specifically focusing on blue pigments, with several industrial applications.

BACKGROUND: Blueberry fruit exhibit atypical climacteric ripening with a non-auto-catalytic increase in ethylene coincident with initiation of ripening. Further, application of ethephon, an ethylene-releasing plant growth regulator, accelerates ripening by increasing the proportion of ripe (blue) fruit as compared to the control treatment. To investigate the mechanistic role of ethylene in regulating blueberry ripening, we performed transcriptome analysis on fruit treated with ethephon, an ethylene-releasing plant growth regulator.
RESULTS: RNA-Sequencing was performed on two sets of rabbiteye blueberry (\'Powderblue\') fruit: (1) fruit from divergent developmental stages; and (2) fruit treated with ethephon, an ethylene-releasing compound. Differentially expressed genes (DEGs) from divergent developmental stages clustered into nine groups, among which cluster 1 displayed reduction in expression during ripening initiation and was enriched with photosynthesis related genes, while cluster 7 displayed increased expression during ripening and was enriched with aromatic-amino acid family catabolism genes, suggesting stimulation of anthocyanin biosynthesis. More DEGs were apparent at 1 day after ethephon treatment suggesting its early influence during ripening initiation. Overall, a higher number of genes were downregulated in response to ethylene. Many of these overlapped with cluster 1 genes, indicating that ethylene-mediated downregulation of photosynthesis is an important developmental event during the ripening transition. Analyses of DEGs in response to ethylene also indicated interplay among phytohormones. Ethylene positively regulated abscisic acid (ABA), negatively regulated jasmonates (JAs), and influenced auxin (IAA) metabolism and signaling genes. Phytohormone quantification supported these effects of ethylene, indicating coordination of blueberry fruit ripening by ethylene.
CONCLUSIONS: This study provides insights into the role of ethylene in blueberry fruit ripening. Ethylene initiates blueberry ripening by downregulating photosynthesis-related genes. Also, ethylene regulates phytohormone-metabolism and signaling related genes, increases ABA, and decreases JA concentrations. Together, these results indicate that interplay among multiple phytohormones regulates the progression of ripening, and that ethylene is an important coordinator of such interactions during blueberry fruit ripening.

The exopolysaccharide production from blueberry juice fermented were investigated. The highest exopolysaccharide yield of 2.2 ± 0.1 g/L (increase by 32.5 %) was reached under the conditions of temperature 26.5 °C, pH 5.5, inoculated quantity 5.4 %, and glucose addition 9.1 % using the artificial neural network and genetic algorithm. Under the optimal conditions, the viable cell counts and total acids were increased by 2.0 log CFU/mL and 1.6 times, respectively, while the content of phenolics and anthocyanin was decreased by 9.26 % and 7.86 %, respectively. The changes of these components affected the exopolysaccharide biosynthesis. The absorption bands of -OH and -CH associated with the main functional groups of exopolysaccharide were detected by Visible near-infrared spectroscopy. The prediction model based on spectrum results was constructed. Competitive adaptive reweighted sampling and the random forest were used to enhance the model\'s prediction performance with the value of RC = 0.936 and RP = 0.835, indicating a good predictability of exopolysaccharides content during fermentation.