Three new iridoids from leaves of Cornus officinalis.

Three new iridoids, cornifins A-C (1-3), together with a known iridoid, were obtained from EtOAc layer of leaves of Cornus officinalis. The structures of new compounds were elucidated on the basis of extensive spectroscopic analyses. Compound 2 showed weak inhibitory activity against lung cancer cell line A-549 with IC50 value of 29.1 µM.

Cytotoxicity of Biodegradable Zinc and Its Alloys: A Systematic Review.

Zinc-based biodegradable metals (BMs) have been developed for biomedical implant materials. However, the cytotoxicity of Zn and its alloys has caused controversy. This work aims to investigate whether Zn and its alloys possess cytotoxic effects and the corresponding influence factors. According to the guidelines of the PRISMA statement, an electronic combined hand search was conducted to retrieve articles published in PubMed, Web of Science, and Scopus (2013.1-2023.2) following the PICOS strategy. Eighty-six eligible articles were included. The quality of the included toxicity studies was assessed utilizing the ToxRTool. Among the included articles, extract tests were performed in 83 studies, and direct contact tests were conducted in 18 studies. According to the results of this review, the cytotoxicity of Zn-based BMs is mainly determined by three factors, namely, Zn-based materials, tested cells, and test system. Notably, Zn and its alloys did not exhibit cytotoxic effects under certain test conditions, but significant heterogeneity existed in the implementation of the cytotoxicity evaluation. Furthermore, there is currently a relatively lower quality of current cytotoxicity evaluation in Zn-based BMs owing to the adoption of nonuniform standards. Establishing a standardized in vitro toxicity assessment system for Zn-based BMs is required for future investigations.

In situ growth of Ca-Zn-P coatings on the Zn-pretreated WE43 Mg alloy to mitigate corrosion and enhance cytocompatibility.

Magnesium (Mg) alloys are potential materials for orthopedic fixation devices but rapid degradation of the materials restricts wider clinical applications. Herein, zinc-incorporated calcium phosphate (Ca-Zn-P) coatings are prepared on the Zn-pretreated WE43 Mg alloy by a hydrothermal technique under relatively stable and favorable conditions. The hydrothermal coating consists of a compact bottom layer of CaZn2(PO4)2∙2 H2O and ZnO granular crystals and a jagged upper layer of CaHPO4. The Zn coating reduces the corrosion current density of WE43 to (3.49 ± 1.60) × 10-5 A cm-2, whereas the Ca-Zn-P/Zn composite coating further reduces it by 3 orders of magnitude in the simulated body fluid (SBF). The charge transfer resistances of the Zn-coated and Ca-Zn-P/Zn-coated alloys increase by 49 and 7176 times to 835 and 1.22 × 105 Ω cm2, respectively. The 7-day immersion results reveal that the Zn coating cannot provide long-term protection to WE43 in SBF because of the formation of galvanic couples between the Zn coating and WE43. In contrast, Ca-Zn-P/Zn-coated WE43 remains intact after soaking for 7 days and furthermore, the Ca-Zn-P coating self-repairs and continues to grow despite dissolution. The compact and adherent Ca-Zn-P bottom layer plays a major role in mitigating corrosion of WE43 by hindering penetration of the aggressive medium and charge transfer of the corrosion reactions resulting in only slight corrosion of the Zn layer. Biologically, the Zn coating reduces attachment and proliferation of MC3T3-E1 pre-osteoblasts on WE43, but the composite coating fosters cell adhesion and proliferation which stems from the good biocompatibility of the hydrothermal layer and relatively stable surface conditions avoiding severe corrosion.

Effects of Vitrinite in Low-Rank Coal on the Structure and Combustion Reactivity of Pyrolysis Chars.

Pyrolysis is a highly promising technology for the efficient utilization of low-rank coal. The structure of coal plays an important role in its utilization. In this paper, the evolution of the char structure during heat treatment (200-800 °C) of Naomaohu coal and its different vitrinite-rich fractions was studied. The functional group structure, aromatic ring structure, and crystallite size of chars were determined by Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, and X-ray diffraction (XRD) spectroscopy, respectively. The results indicated that minerals inhibit the condensation reaction of aromatic rings during pyrolysis. The high vitrinite content in coal is conducive to the formation of larger char crystallite average sizes (L a). The relationship between L a (1.69-3.10 nm) and the Raman band area ratio A (GR+VL+VR)/A D or A D/A all was established. In addition, the combustion performance and kinetics of chars were also investigated. The results showed that the char from high contents of the liptinite fraction has lower combustion reactivity, and demineralization treatment has significantly reduced the combustion reactivity of char.

Characterization of the complete chloroplast genome of Melampyrum roseum.

In this study, the complete chloroplast (cp) genome of Melampyrum roseum was determined through Illumina sequencing method. The complete cp genome of M. roseum was 143,896 bp in length and contained a pair of IR regions (25,210 bp) separated by a small single-copy region (10,292 bp) and a large single-copy region (83,184 bp). The cp genome of M. roseum encoded 117 genes including 78 protein-coding genes, 31 tRNA genes, and 8 rRNA genes. The overall GC content of M. roseum cp genome is 38.1%. By phylogenetic analysis using maximum-likelihood (ML) method, M. roseum was placed in Rhinantheae clade as expected.

Characterization of the complete chloroplast genome of Phtheirospermum japonicum (Rhinantheae).

In this study, we report the complete chloroplast (cp) genome of Phtheirospermum japonicum was determined through Illumina sequencing method. The complete chloroplast genome of Ph. japonicum was 153,397 bp in length and contained a pair of IR regions (25,601 bp) separated by a small single copy region (17,728 bp) and a large single copy region (84,467 bp). The cp genome of Ph. japonicum encoded 125 genes including 86 protein-coding genes, 31 tRNA genes and eight ribosomal RNA genes. The overall GC content of Ph. japonicum cp genome is 38.3%. By phylogenetic analysis using ML method, Ph. japonicum was placed in family Orobanchaceae and showed the closest relationship with Castilleja paramensis.

Two thymol derivatives from the flower buds of Lonicera japonica and their antibacterial activity.

A new monoterpenoid, 7-acetyl-8,9-dihydroxy thymol (1), together with a known one 7,8-dihydroxy-9-buyryl thymol (2), were isolated from the dried flower buds of Lonicera japonica Thunb. Their structures were elucidated on the basis of extensive 1D and 2D NMR spectroscopic data analyses. The potential antibacterial effects of these compounds on Staphylococcus aureus, Escherichia coli, Micrococcus luteus, and Bacillus cereus were evaluated. Interestingly, both compounds 1 and 2 exhibited significant antibacterial activities with IC50 values range from 27.64 ± 2.26 to 128.58 ± 13.26 µg/mL.

One new 19-nor cucurbitane-type triterpenoid from the stems of Momordica charantia.

One new 19-nor cucurbitane-type triterpenoid (3ß,9ß,25-trihydroxy-7ß-methoxy-19-nor-cucurbita-5,23(E)-diene) (1), together with other six known cucurbitane-type triterpenoids (2-7), were isolated from the stems of Momordica charantia L. The chemical structure of 1 was elucidated by extensive 1D NMR and 2D NMR (HSQC, HMBC, COSY and ROESY), MS experiments. Using MTT assay, compound 1 exhibited weak cytotoxicity against HL-60, A-549, and SK-BR-3 cell lines with the IC50 values at 27.3, 32.7 and 26.6 µM, respectively.