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The plant hormone, methyl jasmonate (MeJA), is an orthodox elicitor of secondary metabolites, including terpenoids. Lavandula angustifolia is an important aromatic plant generating, yet few studies have been performed to evaluate the function of MeJA on the biosynthesis of terpenoids in lavender. Five treatments (with concentrations of 0, 0.4, 4, 8, and 16 mM) were set, and the physiological indicators of each group were determined after 0, 6, 12, 24, 48, and 72 h. The results illustrate that (1) MeJA could affect the diurnal rhythm of the emission of volatiles and MeJA acted in a dose-dependent and time-dependent manner; (2) 8 mM MeJA treatment increased the total content of the volatiles, and the contents of monoterpenoids and sesquiterpenoids were up-regulated 0.46- and 0.74- fold than the control at 24 h and 12 h, respectively; (3) after MeJA treatment, all the genes expression analyzed changed to varying degrees, of which 3-carene synthase (La3CARS) gene changed most significantly (7.66- to 38.02- fold than the control); (4) MeJA application was associated with a rise in glandular trichome density. The positive effects of MeJA indicate that the exogenous application of MeJA could be a beneficial mean for studies on the biosynthesis of terpenoids in lavender.

Magnetic agglomeration of CoB nanoparticles in the hydrogen production from the hydrolysis of NaBH4 aqueous solution always degrades their catalytic activity. This work aims at the rational development of robust supported CoB catalyst that is active and stable towards NaBH4 hydrolysis. In this study, PANI nanotubes derived from PS nanofiber templates are firstly synthesized by the polymerization of aniline followed by the template removal. CoB nanoparticles are then decorated into PANI nanotubes via an impregnation and chemical reduction method. It can be found that CoB nanoparticles can be confined into the internal surface of PANI nanotubes which improves the dispersion and anchored stability of CoB nanoparticles. The as-prepared CoB/PANI composite catalyst exhibits a high catalytic performance and recycling stability. The hydrogen production rate as high as 2300 ml. min−1. g − 1 is achieved and the activation energy was calculated to be only 37.75 kJ/mol. Meanwhile, CoB/PANI catalyst displays excellent stability in NaBH4 hydrolysis during five cycles. The experimental results indicated that as-synthesized CoB/PANI composite catalysts are very efficient towards hydrogen production from NaBH4 hydrolysis.

Agglomeration of CoB catalysts is a severe problem in hydrogen generation from NaBH4 hydrolysis. Herein, highly dispersed carbon nanofiber immobilized CoB catalysts (CoB/CN) were synthesized by a combined prereduction and carbonization method, which is used in hydrogen generation from NaBH4 hydrolysis. Morphological evolution of carbon nanofibers, phase structure and elemental distribution of CoB/CN catalysts are explored by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Compared to Co/carbon nanofiber catalysts (Co/CN) without prereduction, CoB/CN catalysts can afford higher CoB dispersity and specific surface area because the migration rate of cobalt species during carbonization is effectively retarded by prereduction. Hence the agglomeration of magnetic CoB nanoparticles can be effectively inhibited. The hydrogen generation experiment shows that CoB/CN catalysts process higher catalytic activity and lower activation energy than Co/CN.

This work focused on fabricating mesoporous bioactive glass nanospheres with large pore (LMBGs) by means of a biphase delamination approach and the self-assembly of the reactants took place at the oil-water interface. The morphology and mesostructure of LMBGs were investigated and the results demonstrated that the well-dispersed LMBGs with a radial mesoporous structure and large pore size could be easily tuned by adjusting the reaction temperature using hexadecyl trimethyl ammonium bromide (CTAB) as a template agent and triethanolamine (TEA) as a hydrolysis catalyst. The special structure and outstanding property of LMBGs probably endowed it with a bright prospect in the application of drug delivery systems.

The aim of this study was to investigate the binding ability of a arginine-glycine-aspartate-serine (RGDS) peptide to dentin and its effect on the dentin remineralization, dentin cohesive strength and intrafibrillar mineralization induced by nanobioactive glass (nBG). The demineralized dentin discs were treated with RGDS and/or nBG and then incubated in stimulated body fluid for 2 weeks. The results of scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction and confocal laser scanning microscopy showed that RGDS could bind to dentin and promote the attachment of nBG. Compared to the nBG group, the RGDS + nBG group induced more apatite formation on the dentin surface and apatite rods inside the dentinal tubules. The results of transmission electron microscopy showed crystal lattice formation in the demineralized dentin matrix treated with nBG or RGDS + nBG, indicating the remineralization of dentin. The RGDS + nBG-treated dentin had the highest dentin cohesive strength in all groups. The self-assembled collagen fibrils exposed to RGDS + nBG exhibited intrafibrillar mineralization. In conclusion, RGDS promoted nBG-induced apatite formation and dentin collagen matrix remineralization, thus enhancing the dentin strength. The results lay a foundation for the wide application of RGDS and nBG in dentin erosion, dentin hypersensitivity, dentin bonding interface improvement, and regenerative dentistry.

The object of this study was to evaluate the effect of bioactive glass (BG) size on mineral formation on dentin surfaces. Totally demineralized dentin discs were treated using BG suspensions with different particle sizes: i.e. , microscale bioactive glass ( m -BG), submicroscale bioactive glass ( sm -BG) and nanoscale bioactive glass ( n -BG). Field-emission scanning electron microscopy and 3D profile measurement laser microscopy were used to observe the surface morphology and roughness. It was found that all BG particles could promoted mineral formation on dentin surfaces, while plug-like depositions were observed on the dentin discs treated by n -BG and they were more acid-resistant. The present results may imply that n -BG has potential clinical application for dentin hypersensitivity treatment.

Introduction This study aimed to evaluate the potential applications of polycaprolactone (PCL)/submicron bioactive glass (smBG) hybrid composites for pulp and dentin tissue regeneration. Methods PCL/smBG hybrid composites were made with novel monodispersive bioactive glass submicrospheres, and pure PCL and bioactive glass samples were used as controls. Surface characteristics were assessed by scanning electron microscopy. Crystalline apatite deposition in vitro was examined after incubation in simulated body fluid. Inductively coupled plasma spectroscopy was used to further analyze the concentration of Si ions released by the scaffolds. Cell adhesion and morphology of human dental pulp cells were observed by immunofluorescence staining. The proliferation and expression of odontogenic-related markers were subsequently investigated using the Cell Counting Kit-8 assay (Beyotime Institute of Biotechnology, Jiangsu, China), Western blotting, and real-time reverse-transcription polymerase chain reaction. Mineralization activity was assessed by alizarin red staining. Results Crystalline apatites were precipitated on the PCL/smBG hybrid and pure bioactive glass surfaces after incubation in vitro , and pure PCL did not exhibit precipitation. Surface deposition on PCL/smBG hybrids presented different topographies and was thicker than on pure bioactive glass scaffolds at a later stage. Human dental pulp cells had a significantly higher proliferation rate on the PCL/smBG hybrid than on the bioactive glass and PCL scaffolds. Furthermore, the integration of smBG into the hybrid scaffold significantly promoted the expression of markers for odontogenic differentiation. More mineralized nodules were generated in the PCL/smBG group than in the other 2 groups. Conclusions PCL/smBG hybrid composites may serve as potential material for pulp repair and dentin regeneration. The physical and chemical properties of the bioactive glass component affect the bioactivity of hybrid composites.

A novel one-pot preparation of chiral N -methyl- N -alkyl Betti bases has been developed involving a highly regioselective N -alkylation of ( S )-(+)-Betti base. The strategy involved formation-cleavage of the oxazine ring and N -methylation with BtCH 2 OH under neutral conditions.

An improved synthesis of homochiral 1-[α-(1-azacycloalkyl)benzyl]-2-naphthols and 1-[α-(2-arylpiperidyl)benzyl]-2-naphthols has been achieved by employing diastereomerically pure α-benzotriazolyl 1-azacycloalka[2,1-b][1,3]oxazines as homochiral precursors, which were obtained by condensation between nonracemic Betti base and dialdehydes in the presence of benzotriazole.