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To facilitate the smooth transition of operational modes in self-sustaining micro-thrusters, this study focuses on a device employing semi-passive flapping wings. Transient numerical methods are used to analyze the variation of flap energy acquisition and propulsion characteristics with pitching frequency, and the relationship between the dominant vortex structure and the force characteristics is analyzed by using the integral momentum theorem and the dynamic mode decomposition (DMD) method. The results indicate that, under the investigated operational conditions, with an increase in the pitching frequency, distinct wake evolution characteristics were observed. In the energy harvesting operational regime, the wake patterns manifest as 2P + mS, 2S + mS, and mS types. During the transitional phase from energy harvesting to propulsion, the wake patterns shift from 2S + mS to 2S transitional types, eventually leading to the manifestation of a reverse Karman vortex street (2S RBVK). In the propulsion operational regime, the wake patterns consist of a reverse Karman vortex street and asymmetric reverse Karman vortex street phenomena. Simultaneously, it was observed that the transition of flapping-wing performance from energy harvesting to propulsion conditions delays behind the transformation of vortex street structures. This delay is attributed to the necessity for the flapping-wing device to overcome its own resistance before generating a net effective propulsive force. The contributions of unsteady wake to thrust primarily encompass vortex thrust, thrust due to localized fluid acceleration, induced momentum force, and induced pressure force. As the pitching frequency increases, the influence of wake vortices on propulsion also intensifies. The contribution of wake vortices to flapping-wing propulsion is determined by the spatial distribution of Lamb vectors and localized fluid accelerations. The conclusions drawn from the dynamic modal analysis and reconstructed flow field analysis of wake vortices align with the findings of the investigation of wake vortices based on the integral momentum theorem. [ABSTRACT FROM AUTHOR]

Sugarcane leaves have been extensively consumed as a herbal tea for centuries in China, which is an economically important crop containing multiple health benefits. Here we report the structure and in vitro antitumor activity of a purified sugarcane leaf polysaccharide (SLP70–1). SLP70–1 is a homogeneous heteropolysaccharide made up of mannose, glucose, and galactose with a molar ratio of 1.00: 1.89: 2.83. Additionally, the molecular weight of SLP70–1 was 3.23 kDa. Linkage together with NMR examination demonstrated the structural foundation of SLP70–1 were consisted of →4)- α -D-Gal p -(1→, →4)- α -D-Glc p -(1→, →2)- β -D-Man p -(1→, →3)- β -D-Gal p -(1→, →4,6)- β -D-Gal p -(1→, →6)- α -D-Gal p -(1→, →3,6)- α -D-Glc p -(1→ and α -D-Glc p -(1→，and the side chain was confirmed to be →4)- α -D-Glc p -(1→ and →6)- α -D-Gal p -(1→. According to an in vitro cell experiment, SLP70–1 could markedly decrease the survival ability of cancer cells exhibiting concentration dependence, including the survival rate of cancer cells in the lungs, colon, cervix, kidney, and breast, implying potent antitumor activity. In summary, SLP70–1 exhibits features that qualify it as a promising antitumor adjuvant candidate. • A novel polysaccharide SLP70-1 was obtained from sugarcane leaves. • The glycosidic bond types and linkage patterns were successfully clarified. • SLP70-1 exhibited a certain antitumor effect in vitro. • The underlying structure-function relationship was elucidated. [ABSTRACT FROM AUTHOR]

A novel strategy was devised to synthesize robust nanocarriers by conjugating fish collagen peptides (FCP) with Ampelopsis grossedentata polysaccharide (AGP), culminating in the creation of FCP-AGP nanoparticles (FCAGPs) for advanced drug delivery systems. The innovative approach entailed the systematic investigation of particle size, zeta potential, and surface hydrophobicity alterations in FCAGPs upon varying AGP concentrations. The optimized FCAGP-4 nanoparticles, boasting a precisely engineered AGP content of 2.0 % (w/v) and an average particle diameter finely tuned to 353.2 ± 10.5 nm, demonstrated outstanding characteristics in dispersibility, stability, and emulsifying capacity. Furthermore, the water contact angle of FCAGP nanoparticles notably increased from 46.3 ± 2.8° to 70.2 ± 5.6°, indicating enhanced surface hydrophobicity. The mechanism by which FCAGP nanoparticles were attached to the surface of oil droplets to stabilize the emulsions was elucidated by confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). Significantly, a modified sample pretreatment technique was employed to demonstrate clearly the emulsion phase interface on the SEM.Innovative FCAGP-stabilized Pickering emulsions achieved 65.39 % in DMY bioavailability, facilitating its slow-release and enhanced bioaccessibility during in vitro digestion. Pickering emulsions loaded DMY demonstrated improved stability and sustained release under simulated digestive conditions, bolstering its therapeutic efficacy. Our findings solidify the theoretical basis for green synthesis of propeptide-polysaccharide nanoparticles and introduce a novel strategy for targeted propeptide Pickering emulsions in drug delivery, highlighting the transformative potential of FCAGP nanoparticles in enhancing lipophilic drug bioavailability and pharmacological impact. [Display omitted] • Surface Hydrophobicity: Protein surface hydrophobicity enhanced by Ampelopsis grossedentata polysaccharide modification. • Pickering Emulsion Stability: AGP significantly improves the storage stability of Pickering emulsions. • Interfacial Dynamics Insight: Advanced styrene/V65 technology reveals new details of emulsion phase interfaces. • Enhanced Bioavailability: Pickering emulsions increase dihydromyricetin bioavailability as a delivery system. [ABSTRACT FROM AUTHOR]

[Display omitted] • Zein/Sugarcane leaves polyphenols (SGLpZ) covalent nanoparticles were successfully prepared. • Pickering Emulsions stabilized by SGLpZ with ultrasound showed high stability in lipid oxidation during storage. • SGLp modification Pickering emulsions (SZP) exhibited low free fatty acids release in in-vitro digestion. • SZP showed high safety in hemocompatibility and cytotoxicity assays in-vitro. This study firstly used sugarcane leaf polyphenols (SGLp) to modify zein to form covalent nanoparticles (SGLpZ) and used SGLpZ as an emulsifier to stabilize pickering emulsions (SZP) via ultrasonic method. The results showed that the addition of SGLp could alter the physicochemical properties of zein, including improving increasing the hydrophilicity of zein and the antioxidant properties of zein (three basic antioxidant activities test in vitro). SGLpZ could be able to form a dense film on the surface of the pickering emulsions which inhibited lipid oxidation as the concentration of SGLp increased at 4 ℃ for 20 days, thus stabilizing pickering emulsions (SZP). Further assessment of storage stability of pickering emulsions stabilized by SGLp was evaluated via measuring the free fatty acids (FFA) release in vitro gastrointestinal digestion. The results showed that the FFA release of SZP decreased from 20.61 ± 0.10% to 16.14 ± 0.69%. In addition, SGLp gave SZP a yellow color, which inspired that SZP could be used in the food industry to make yellow-colored functional foods. Finally, the safety of SZP initially assessed by in-vitro hemocompatibility and cytotoxicity (MTT) assays. In conclusion, our fingdings were beneficial for the further design and development of SGLp in food fields and enabled the development a new type in functional protein-plant polyphenols food pickering emulsions. [ABSTRACT FROM AUTHOR]

Pickering emulsion have been widely used to encapsulate bioactives with the aim of preventing degradation, improving bioavailability and achieving the effect of slow release. Curcumin (Cur), as a bioactive compound, was famous as its excellent beneficial human health functions. However, the low solubility and susceptibility to environmental influences limit the application of Cur. In our previous study, the covalent nanoparticles (sugarcane leaf polyphenols-zein, SGLpZ) with excellent antioxidant capacity were successfully fabricated. In addition, the pickering emulsion stabilized using SGLpZ with significance storage stability and antioxidant properties, which inspired us for Cur delivery application. Therefore, in this study, SZP (pickering emulsion stabilized by SGLpZ) were prepared and were firstly used to delivery Cur evaluation. Results exhibited that the mechanism of excellent stabilization of SZP may be due to the wide range of O/W phase interfaces with SGLpZ, which could be further used as a delivery system for Cur. An in-vitro simulated digestion suggested that SZP provided better protection to Cur under three different conditions (different Na+ concentration, temperatures and UV exposure times), compared to ZZP (pickering emulsion stabilized by zein nanoparticles alone). SZP was able to achieve a slow release of Cur as well as the high bioaccessibility of Cur during the in-vitro simulated digestion. Finally, Cur, Cur-ZZP and Cur-SZP inhibited respectively by 33.20±1.00%, 53.26±0.94% and 71.59±0.14% (p ＜0.05) at the Cur concentration of 20 μg/mL in the in-vitro inhibition of AAPH-induced erythrocyte hemolysis assay. The study indicated that the pickering emulsion stabilized by SGLpZ was a reliable Cur delivery system and provided a novel idea of food material application for bioacitive substances delivery. [Display omitted] • A green-sustainable pickering emulsion stabilized by Sugarcane leaf polyphenols-Zein nanoparticles was firstly prepared. • Cur-SZP for better results compared with curcumin and Cur-ZZP in three different external environments. • Cur-SZP achieved slow release and improved bioavailability of curcumin in in-vitro digestion. • The inhibitory effect of Cur-SZP on hemolysis of red blood cells was studied. [ABSTRACT FROM AUTHOR]