Investigating the impact of ultrasound-assisted treatment on the crafting of mulberry leaf protein and whey isolate complex: A comprehensive analysis of structure and functionality.

Mulberry leaf protein (MLP) is a nutrient-rich protein, but its applicability is limited because of its poor solubility. To address this issue, this study combines MLP with whey protein isolates (WPI), known for the high nutritional value, and subsequently forms composite protein nanoparticles using the ultrasound-assisted pH shifting method. Microscopic observation and SDS-PAGE confirmed the binding between these two proteins. Fluorescence spectra and Fourier Transform infrared spectroscopy (FTIR) analysis supported the involvement of electrostatic interactions, hydrophobic attractions, and hydrogen bonding in the formation of stable complex nanoparticles. The interactions between the proteins became stronger after ultrasound-assisted pH-shifting treatment. Solubility, emulsification capacity, foaming, and antioxidant activity, among other indicators, demonstrate that the prepared composite nanoparticles exhibit favorable functional properties. The study successfully illustrates the creation of protein-based complex nanoparticles through the ultrasound-assisted pH shifting method, with potential applications in the delivery of bioactive compounds.

Effect of various oligosaccharides on casein solubility and other functional properties: Via Maillard reaction.

This study explored the improvement of casein (CN)'s properties by conjugating it with oligosaccharides, namely, fructooligosaccharide (FOS), galactooligosaccharide (GOS), isomaltooligosaccharide (IMO), and xylo-oligosaccharide (XOS) via Maillard reaction to identify the most optimal oligosaccharides and modification conditions. The degree of grafting was 30.5 ± 0.41 % for CN-FOS, 33.7 ± 0.62 % for CN-GOS, 38.9 ± 0.51 % for CN-IMO, and 43.7 ± 0.54 % for CN-XOS. With the degree of grafting rising, more oligosaccharides were conjugated, causing greater changes in CN properties. The CN-XOS underwent significant alterations, as the introduction of oligosaccharides led to a decrease in particle size by around 51 nm. Furthermore, the hydroxyl groups caused a reduction in surface hydrophobicity, which in turn decreased the proportion of hydrophobic groups. The solubility of CN-XOS increased significantly at pH 3, by approximately 30.99 %. Additionally, the conjugation of oligosaccharides substantially boosted the rates of DPPH, ABTS, and -OH radical scavenging by 4.61 times, 2.20 times, and 2.58 times, respectively, and also improved the thermal stability of the modified CN. Moreover, the process lowered the protein digestibility, possibly enhancing its applicability as an active substance transporter. This research offers additional theoretical backing for altering CN with oligosaccharides and implementing it in the food and pharmaceutical sectors.

Electrospun Nanofibrous P(DLLA-CL) Balloons as Calcium Phosphate Cement Filled Containers for Bone Repair: in Vitro and in Vivo Studies.

The spinal surgeon community has expressed significant interest in applying calcium phosphate cement (CPC) for the treatment of vertebral compression fractures (VCFs) and minimizing its disadvantages, such as its water-induced collapsibility and poor mechanical properties, limiting its clinical use. In this work, novel biodegradable electrospun nanofibrous poly(d,l-lactic acid-ϵ-caprolactone) balloons (ENPBs) were prepared, and the separation, pressure, degradation, and new bone formation behaviors of the ENPBs when used as CPC-filled containers in vitro and in vivo were systematically analyzed and compared. CPC could be separated from surrounding bone tissues by ENPBs in vitro and in vivo. ENPB-CPCs (ENPBs serving as CPC-filled containers) exerted pressure on the surrounding bone microenvironment, which was enough to crush trabecular bone. Compared with the CPC implantation, ENPB-CPCs delayed the degradation of CPC (i.e., its water-induced collapsilibity). Finally, possible mechanisms behind the in vivo effects caused by ENPB-CPCs implanted into rabbit thighbones and pig vertebrae were proposed. This work suggests that ENPBs can be potentially applied as CPC-filled containers in vivo and provides an experimental basis for the clinical application of ENPBs for the treatment of VCFs. In addition, this work will be of benefit to the development of polymer-based medical implants in the future.

Self-assembly of regenerated silk fibroin from random coil nanostructures to antiparallel ß-sheet nanostructures.

In this work, we studied the effects of incubation concentration and time on the self-assembly behaviors of regenerated silk fibroin (RSF). Our results showed the assembly ways of RSF were concentration-dependent and there were four self-assembly ways of RSF: (i) At relatively low concentration (≤0.015%), RSF molecules assembled into protofilaments (random coil), and then the thickness decreased and the secondary conformation changed to antiparallel ß-sheet; (ii) at the concentration of 0.015%, RSF molecules assembled into protofilaments (random coil), and then assembled into protofibrils (antiparallel ß-sheet). The protofibrils experienced the appearance and disappearance of phase periodic intervals in turn; (iii) at the concentration of 0.03%, RSF molecules assembled into bead-like oligomers (random coil), and then assembled into protofibrils (antiparallel ß-sheet), and finally the height and phase periodic intervals of RSF protofibrils disappeared in turn; and (iv) at the relatively high concentration (≥0.15%), RSF molecules assembled into protofilaments (random coil), then aggregated into blurry cuboid-like micelles (random coil), and finally self-arranged to form smooth and clear cuboid-like micelles (antiparallel ß-sheet). These results provide useful insights into the process by which the RSF molecules self-assemble into protofilaments, protofibrils and micelles. Furthermore, our work will be beneficial to basic understanding of the nanoscale structure formations in different silk-based biomaterials.

Tip-induced micropatterning of silk fibroin protein using in situ solution atomic force microscopy.

Silk fibroin (SF) is a promising candidate for a variety of application in the fields of tissue engineering, drug delivery, and biomedical optics. Recent research has already begun to explore the construction of nano- and micropatterned SF films under ambient environment. The structure and biocompatibility of SF are dependent on SF state (solution or solid) and the method of drying the SF solution to prepare various biomaterials such as films, sponges, and fibers. Therefore, it is important to explore the construction of SF nano- and micropatterns under aqueous solution. This paper reports a novel application of atomic force microscopy (AFM) under liquid for direct deposition of the relatively hydrophobic protein SF onto hydrophilic mica. We demonstrate that the AFM tip, in either the contact or the tapping mode, can fabricate SF micropatterns on mica with controlled surface topography. We show that the deposition process requires a mechanical force-induced SF sol-gel transition followed by a transfer to the mica surface at the tip-surface contact, and the efficiency of this process depends on not only AFM operation mode but also the SF bulk concentration, the SF amount on mica, and the AFM tip spring constant.