Nanocomposites of Chitosan/Graphene Oxide/Titanium Dioxide Nanoparticles/Blackberry Waste Extract as Potential Bone Substitutes

New technologies based on nanocomposites of biopolymers and nanoparticles inspired by the nature of bone structure have accelerated their application in regenerative medicine, thanks to the introduction of reinforcing properties. Our research incorporated chitosan (CS) covalently crosslinked with glutaraldehyde (GLA) beads with graphene oxide (GO) nanosheets, titanium dioxide nanoparticles (TiO2), and blackberry processing waste extract (BBE) and evaluated them as partial bone substitutes. Skullbone defects in biomodels filled with the scaffolds showed evidence through light microscopy, scanning electron microscopy, histological studies, soft tissue development with hair recovery, and absence of necrotic areas or aggressive infectious response of the immune system after 90 days of implantation. More interestingly, newly formed bone was evidenced by elemental analysis and Masson trichromacy analysis, which demonstrated a possible osteoinductive effect from the beads using the critical size defect experimental design in the biomodels. The results of this research are auspicious for the development of bone substitutes and evidence that the technologies for tissue regeneration, including chitosan nanocomposites, are beneficial for the adhesion and proliferation of bone cells.

Synthesis of Al(OH)3 nanoparticles from Indonesian bauxite and tomato waste extract as chelating agent for nanofluids applications

This study aimed to determine the effect of calcination time on the properties of Al(OH)3 or gibbsite nanoparticles in the sol-gel process, which was then used as the basic material in the manufacturing of water-Al(OH)3 based nanofluids. Nanofluid is a mixture of basic fluids such as water with solid nanoparticles. Al(OH)3 nanoparticles have been successfully synthesized from Indonesia local mineral bauxite using the sol-gel method by utilizing tomato waste extract as a chelating agent at a calcination temperature of 700ºC for 1 hour, 3 hours, and 5 hours. The obtained calcined powders were characterized using X-ray diffractometer (XRD). The evaluation toward nanofluids application based on theirs stability based on visual observation and zeta potential. Based on XRD analysis, all calcined powders has single Al(OH)3 or gibbsite phase. Increasing the calcined temperature gave impact on crystallinity, crystallite size, and reorientation of crystal. The water-Al(OH)3 nanofluid was relatively less stable with a zeta potential value of -25.2 mV; -26.4 mV; and -17.4 mV for calcination time 1 h, 3 h, and 5 h, respectively.

Characteristics and Valorization Potential of Fermentation Waste of Greengage (Prunus mume)

Greengage wine is gaining increasing attention in Asia for its rich nutritional elements and medicinal value. However, the treatment of the fermentation waste after brewing is a problem that remains unsolved. This work proposed to valorize the fermentation waste extract by a simple centrifugation. The bioactive compounds of the fermentation waste were investigated, including total flavonoids, total phenols, specific phenols and volatile compounds. The antioxidant and antibacterial capacities of the waste extract were also evaluated. The results revealed that the total phenol (1.34 mg GAE/g EPW) and total flavonoid (1.17 mg RE/g EPW) of the fermentation waste extract were still considerable. The fermentation waste also showed high DPPH radical scavenging capacity (5.39 μmol TE/g EPW) and high ABTS radical scavenging capacity (9.80 μmol TE/g EPW). Both GC-MS and LC-MS analysis identified key bioactive compounds, such as linalool, terpineol, β-ionone, neochlorogenic acid and chlorogenic acid, which have high antioxidant capacity and strong, thermal-stable antibacterial capacity. All these characteristics show a promising future for valorized fermentation waste, for example, in food additives or mouthwash.

Neuritogenic Activities of Various Kappaphycus alvarezii Extracts in Hippocampal Neurons

The carrageenophyte Kappaphycus alvarezii seaweed is known to have neuritogenic activities. Post-harvest treatment of seaweed affects its biological activities. Five drying treatments of K. alvarezii, including oven-drying, sun-drying, freeze-drying, shade-drying, and salting followed by shade-drying, were evaluated for their effects on neuritogenic activities. We also evaluated the neuritogenic activity of different parts of K. alvarezii thalli and its carrageenan waste. Neuron cells of the 19th day pregnant rat fetuses were collected from the hippocampus by brain dissection. Neuron cells were isolated by dissociation of the hippocampal tissue. Cells were plated onto poly-DL-lysine-coated glass coverslips in 24-well plates and treated with extracts. All tested extracts were obtained from maceration using 95% ethanol. Freeze and shade-drying extracts exhibited significantly higher neuritogenic activities (p 0.05) compared to that of the vehicle control. Carrageenan waste also significantly promoted the neuritogenic activities (p 0.05) with an optimal dose at 1 µg mL-1. Old and young thalli showed insignificant differences in neuritogenic activities. The carrageenan waste extract retained neuritogenic activities. Thus, the utilization of carrageenan waste for neuritogenic material provides added value to the waste in the carrageenan industry. Freeze and shade dried K. alvarezii can be used as a neuritogenic agent to provide optimum biological activity.