Records of Natural Products

Bioassay-guided led to the isolation of five compounds, including a new picrotoxane-type sesquiterpene lactone, aduncin C (1), together with four known ones (2-5) from Dendrobium huoshanense. Their structures were elucidated by means of extensive spectroscopic analysis. Biological evaluation of the isolates against four human cancer cell lines indicated broad-spectrum and cytotoxic activities with IC50 values ranging from 4.08 to 26.75 μM. Among them, α-dihydropicrotoxinin (3) exhibited significant cell proliferation inhibitory activity, especially for HL-60 (IC50 5.81 μM), MCF- 7 (IC50 6.49 μM), SW-480 (IC50 6.80 μM), respectively.

This study investigates the activation of human immune cells (T, B, and NK cells, and granulocytes) by the ethanolic and aqueous extracts of Scutellaria baicalensis root (SBR) and to identify the compounds responsible for such an effect. The cell activation was determined by expression of the cell surface glycoprotein CD69 (cluster of differentiation 69), as measured by flow cytometry. The content of the main flavonoids in SBR extracts was estimated by high performance liquid chromatography with a diode array detector. NK cells were substantially activated by the SBR ethanolic extract (25–200 µg/mL), whereas B cells were activated on a lower scale. NK cells were slightly activated by the SBR aqueous extract (100–200 µg/mL). Wogonoside and baicalin, two major flavonoids present in the SBR extracts, exhibited the highest activation effect on NK cells. The content of baicalin, wogonoside, and baicalein accounted for 201.2, 47.7, and 3.4 mg/g in the ethanolic extract; and for 150.4, 33.6, and 4.6 mg/g in the aqueous extract, respectively. This study shows the immune-stimulating properties of SBR extracts and identifies their active compounds. This data may support the potential utilization of SBR for strengthening the human immune system against bacterial and viral infections.

The genus Cinnamomum belongs to the family Lauraceae and contains about 250 species. Cinnamomum plants have great economic value and have been widely used in the pharmaceutical, chemical, food and cosmetic industries. A great deal of research on the chemical constituents and their various biological activities has been conducted on only 20 species of Cinnamomum. We have already summarized the chemical structures and bioactivities of terpenoids from Cinnamomum. Herein, we give an update on other types of compounds and their biological activities. According to the findings, 380 chemical compounds obtained from Cinnamomum, including lignans, butanolides, flavonoids, phenylpropanoids, alkaloids and other compounds are summarized, and their corresponding unique chemical structures and significant biological activities are introduced in this paper.

The aim of the present study was to evaluate the variations in the phytochemical compositions and the antimicrobial activities of Syzygium grande and Oenanthe javanica leaf extracts against Bacillus sp. The antibacterial activity of the methanol, 70% methanol, ethyl acetate, and hexane extracts of both plant species were examined in vitro, against various Bacillus species. In addition, the 1H Nuclear Magnetic Resonance (1H NMR) spectroscopy-based metabolomics was employed to gain insights into the correlations between the chemical constituents of the bioactive extract to the biological activity. The hexane extract of S. grande leaves and methanolic extract of O. javanica leaves showed more potent anti-Bacillus activity, among the test extracts. Principal component analysis (PCA) successfully differentiated the extracts on the basis of their metabolite profiles.  The results of the Partial Least Square (PLS) analysis showed that the non-polar compounds of the hexane extract of S. grande (alanine, betulin, β-sitosterol, β-caryophyllene, acetic acid and 3-hydroxybutyric acid) were strongly correlated to its anti-Bacillus activity. On the other hand, choline, ellagic acid, and gallic acid, the metabolites present in the methanolic extract of O. javanica, were strongly correlated to its anti-Bacillus activity.  On this basis, it was therefore concluded that these conmpounds could be the potential bioactive constituents, contributing to the anti-Bacillus activity of the individual plant species.  Further in-depth investigations into the potential utilization of the two plants for useful applications in managing and control of Bacillus sp., will help pave the way towards their valorization.