Anti-inflammatory and antinociceptive effects, toxicity, and phytochemical analysis of Beaumontia grandiflora Wall.

Preliminary pharmacological studies revealed that the EtOAc fraction (BGEA) might be the main active fraction with anti-inflammatory and antinociceptive effects in Beaumontia grandiflora Wall. Further assays on BGEA at doses of 200, 400, and 800 mg/kg using four animal models showed that it could inhibit the xylene-induced ear edema, carrageenan-induced paw edema, and acetic acid-induced writhing and prolong the latency time in the hot-plate test. ELISA analysis revealed that the anti-inflammatory activity of BGEA might be associated with the decrease of TNF-α, IL-1ß, and IL-6 levels and the increase of the IL-10 level. The acute toxicity test showed that except for the n-BuOH fraction, the LD50 values of the extract and other three fractions were higher than 2000 mg/kg bw. Finally, 14 compounds were identified from BGEA by LC-MS. This research provides some basis for the folk use of B. grandiflora in the treatment of inflammation and pain-related diseases.

Experimental Study on Synergistic Demulsification of Microwave-Magnetic Nanoparticles.

Owing to the difficulty in the demulsification of heavy oil-in-water (O/W) emulsions, the demulsification rules of magnetic nanoparticles, microwave radiation, and magnetic-nanoparticle-assisted microwaves were investigated in this study. The surface potential and droplet size of the emulsion under different demulsification conditions were investigated by using a ζ potentiometer and polarizing microscopy to reveal the mechanism of demulsification. The results showed that γ-Fe2O3 exhibited the best demulsification performance among the six magnetic nanoparticles used for demulsification. With an increase in the concentration of γ-Fe2O3, the water separation of the heavy O/W emulsion first increased and then decreased, and with a decrease in pH, the demulsification performance gradually increased. The experimental results showed that microwave demulsification had an optimal power. The demulsification efficiency was significantly improved at the synergistic action between magnetic nanoparticles and the microwave, proving that magnetic nanoparticles had a promoting effect on microwave demulsification. In addition, the recycling experiment results showed that the magnetic nanoparticles exhibited good recyclability and reusability. Finally, a temperature field model of the emulsion under the synergistic effect of microwaves and magnetic nanoparticles was established and evaluated. Both before and after the addition of the magnetic nanoparticles, the theoretical temperature of the heavy O/W emulsion was consistent with the experimental temperature at different microwave powers and radiation times.

Isolation and Bioinspired Total Synthesis of Rugosiformisin A, A Skeleton-Rearranged Abietane-Type Diterpenoid from Isodon rugosiformis.

Rugosiformisin A, a skeleton-rearranged abietane-type diterpenoid with a spiro[4.5]decane motif, was isolated from Isodon rugosiformis. Its structure was unambiguously established via NMR spectroscopic analysis and single-crystal X-ray diffraction. A bioinspired asymmetric synthesis of rugosiformisin A was achieved in 15 steps with 2.7% overall yield. The synthesis features an iridium-catalyzed asymmetric polyene cyclization and a semipinacol rearrangement.

Creating Highly Specific Chemically Induced Protein Dimerization Systems by Stepwise Phage Selection of a Combinatorial Single-Domain Antibody Library.

Protein dimerization events that occur only in the presence of a small-molecule ligand enable the development of small-molecule biosensors for the dissection and manipulation of biological pathways. Currently, only a limited number of chemically induced dimerization (CID) systems exist and engineering new ones with desired sensitivity and selectivity for specific small-molecule ligands remains a challenge in the field of protein engineering. We here describe a high throughput screening method, combinatorial binders-enabled selection of CID (COMBINES-CID), for the de novo engineering of CID systems applicable to a large variety of ligands. This method uses the two-step selection of a phage-displayed combinatorial nanobody library to obtain 1) "anchor binders" that first bind to a ligand of interest and then 2) "dimerization binders" that only bind to anchor binder-ligand complexes. To select anchor binders, a combinatorial library of over 109 complementarity-determining region (CDR)-randomized nanobodies is screened with a biotinylated ligand and hits are validated with the unlabeled ligand by bio-layer interferometry (BLI). To obtain dimerization binders, the nanobody library is screened with anchor binder-ligand complexes as targets for positive screening and the unbound anchor binders for negative screening. COMBINES-CID is broadly applicable to select CID binders with other immunoglobulin, non-immunoglobulin, or computationally designed scaffolds to create biosensors for in vitro and in vivo detection of drugs, metabolites, signaling molecules, etc.

COMBINES-CID: An Efficient Method for De Novo Engineering of Highly Specific Chemically Induced Protein Dimerization Systems.

Chemically induced dimerization (CID) systems, in which two proteins dimerize only in the presence of a small molecule ligand, offer versatile tools for small molecule sensing and actuation. However, only a handful of CID systems exist and creating one with the desired sensitivity and specificity for any given ligand is an unsolved problem. Here, we developed a combinatorial binders-enabled selection of CID (COMBINES-CID) method broadly applicable to different ligands. We demonstrated a proof-of-principle by generating nanobody-based heterodimerization systems induced by cannabidiol with high ligand selectivity. We applied the CID system to a sensitive sandwich enzyme-linked immunosorbent assay-like assay of cannabidiol in body fluids with a detection limit of ∼0.25 ng/mL. COMBINES-CID provides an efficient, cost-effective solution for expanding the biosensor toolkit for small molecule detection.

Scopariusols L-T, nine new ent-kaurane diterpenoids isolated from Isodon scoparius.

Nine new ent-kaurane diterpenoids, named scopariusols L-T (1-9), were isolated from the aerial parts of Isodon scoparius. Their structures were characterized mainly by analyzing the NMR and HR-ESI-MS data, and the absolute configuration of 1 was determined by single-crystal X-ray diffraction. Compound 1 was active against five human tumor cell lines (HL-60, SMMC-7721, A-549, MCF-7, and SW-480), and it also inhibited NO production in LPS-stimulated RAW264.7 cells, with an IC50 value of 0.6 µmol·L-1.

Bioactive ent-kaurane diterpenoids from Isodon rubescens.

Seven previously undescribed 7,20-epoxy-ent-kaurane diterpenoids, isojiangrubesins A-G, along with seventeen known ones, were isolated from the aerial parts of Isodon rubescens. Their structures were characterized on the basis of spectroscopic methods and signal-crystal X-ray diffraction. All of these compounds were evaluated for their in vitro cytotoxicity against five human tumor cell lines (HL-60, SMMC-7721, A-549, MCF-7, and SW480). Four isolates exhibited significant inhibitory ability against all cell lines, with IC50 values ranging from 0.5 to 6.5 µM; They also strongly inhibited NO production in LPS-stimulated RAW264.7 cells.

Structurally Diverse Diterpenoids from Isodon scoparius and Their Bioactivity.

Fourteen new diterpenoids (1-14) based on four skeletal types and two known analogues (15 and 16) were isolated from the aerial parts of Isodon scoparius. Compound 2 is the first ent-kaurane diterpenoid featuring a 1,11-ether bridge, and the structures of these new compounds were established mainly by NMR and MS methods. The absolute configurations of 1 and 5 and the relative configuration of 3 were determined using single-crystal X-ray diffraction. The absolute configuration of 14 was determined by comparison of the experimental and calculated electronic circular dichroism spectra. Compounds 1, 4, and 15 were active against five human tumor cell lines (HL-60, SMMC-7721, A-549, MCF-7, and SW-480), and they also inhibited NO production in LPS-stimulated RAW264.7 cells, with IC50 values of 1.0, 3.1, and 1.8 µM, respectively.

Ent-Abietanoids Isolated from Isodon serra.

Four new ent-abietane diterpenoids, along with four known ones were isolated from the aerial parts of Isodon serra, a traditional Chinese folk medicine. The new diterpenoids were named as serrin K (1), xerophilusin XVII (2), and enanderianins Q and R (3 and 4), while the known ones were identified as rubescansin J (5), (3α,14ß)-3,18-[(1-methylethane-1,1-diyl)dioxy]-ent-abieta-7,15(17)-diene-14,16-diol (6), xerophilusin XIV (7), and enanderianin P (8), respectively. Their structures were elucidated by extensive spectroscopic analysis and comparison with the literature. Compound 1 showed remarkable inhibitory activity towards NO production in LPS-stimulated RAW264.7 cells (IC50 = 1.8 µM) and weak cytotoxicity towards five human tumor cell lines (HL-60, SMMC-7721, A-549, MCF-7, SW480).

Bioactive ent-kaurane diterpenoids from Isodon serra.

Nine 7,20-epoxy-ent-kaurane diterpenoids (15-acetylmegathyrin B, serrin E, 14ß-hydroxyrabdocoestin A, serrin F, serrin G, 11-epi-rabdocoestin A, serrin H, serrin I, and 15-acetylenanderianin N), along with seven known ones, were isolated from the aerial parts of Isodon serra. Their structures were elucidated by extensive spectroscopic analysis, and the absolute configuration of 15-acetylmegathyrin B was determined by signal-crystal X-ray diffraction. All of these compounds were evaluated for their cytotoxic activities against five human tumor cell lines (HL-60, SMMC-7721, A-549, MCF-7, SW480). Serrin F, rabdocoestin B and 1α,11ß-dihydroxy-1α,11ß-acetonide-7α,20-epoxy-ent-kaur-16-en-15-one showed cytotoxic activities against all cell lines, with IC50 values ranging from 0.7 to 4.6 µM; serrin F also strongly inhibited NO production in LPS-stimulated RAW264.7 cells. Otherwise, 14ß-hydroxyrabdocoestin A, serrins H and I, as well as enanderianin N and megathyrin B, also exhibited inhibitory effects towards NO production, while no cytotoxicity against five cell lines was detected.

Cytotoxic and anti-inflammatory ent-kaurane diterpenoids from Isodon wikstroemioides.

Seven new ent-kaurane diterpenoids, isowikstroemins A-G (1-7), were isolated from EtOAc extracts of the aerial parts of Isodon wikstroemioides. Their structures were elucidated by extensive spectroscopic analysis. The isolates were evaluated for their cytotoxicity against five human tumor cell lines, and compounds 1-4 exhibited significant activity with IC50 values ranging from 0.9 to 7.0 µM. In addition, compounds 1, 2, 3, 4, and 7 exhibited inhibitory activity against nitric oxide (NO) production in LPS-activated RAW264.7 macrophages.

Cytotoxic ent-kaurane diterpenoids from Isodon wikstroemioides.

Phytochemical investigation of EtOAc extracts of the aerial parts of Isodon wikstroemioides afforded 18 new ent-kaurane diterpenoids (wikstroemioidins E-V, 1-18), along with 17 known analogues (19-35). The absolute configurations of 1 and 16 were confirmed by single-crystal X-ray diffraction analysis. The isolates were screened against five human tumor cell lines; compounds 3, 4, 9, 11-13, 23, 25-28, and 33 exhibited significant cytotoxic activity against all five, with IC50 values ranging from 0.4 to 5.1 µM. In addition, 17 of the isolates strongly inhibited nitric oxide production in LPS-activated RAW264.7 macrophages.

Diterpenoids from Isodon sculponeatus.

Phytochemical investigation of the aerial parts of Isodon sculponeatus afforded six new 7,20-epoxy-ent-kauranoids, sculponins U-Z (1-6), and 11 known diterpenoids (7-17). The structures of these new compounds were elucidated primarily by means of extensive spectroscopic analysis, and the absolute configuration of 1 was determined by single crystal X-ray diffraction. Compound 5 exhibited weak cytotoxic activity against HL-60, SMMC-7721, MCF-7, and SW-480 cell lines, and it also inhibited NO production in LPS-stimulated RAW264.7 cells, with IC50 value of 13.8 µM.

Enmein-type 6,7-seco-ent-kauranoids from Isodon sculponeatus.

Fourteen enmein-type 6,7-seco-ent-kaurane diterpenoids, seven new ones (sculponins M-S, 1-7) and seven known compounds (8-14), were isolated from the aerial parts of Isodon sculponeatus . Compound 1 is the first example of an ent-kauranoid, possessing a 11,12-epoxy group, and compounds 6 and 7 have a rare 3,6-epoxy group. The structures were established primarily by NMR and MS methods, and the absolute configurations of 1, 3, and 6 were determined by single-crystal X-ray diffraction. Compound 14 showed significant cytotoxic activity against five human tumor lines, with IC50 values ranging from 1.0 to 3.5 µM, and it also inhibited NO production in LPS-stimulated RAW264.7 cells, with an IC50 value of 2.2 µM.