Biological Activity of Chemical Constituents Isolated from Strain Chlamydomonas sp. KSF108 (Chlamydomonadaceae)

This study focused on investigation of the immunosuppressive inhibitory effect through determination of IL-2 production of nine compounds (1 − 9) isolated from Chlamydomonas sp. KSF108. Among them, compounds 1, 5, and 6 displayed moderately inhibitory effects on IL-2 production at a concentration of 100 μM. In addition, the related ones including cytotoxic, anti-inflammatory, and anti-oxidant activities were also elucidated. 6 further displayed cytotoxic activity against the MCF-7 cell line, with an IC50 value of 17.2 μM and 4, 6 − 7, and 9 possessed significant DPPH radical scavenging activity, with IC50 values ranging from 3.1 to 4.4 μM. To the best of our knowledge, this is the first report on the bioactivity of isolated chemical constituents from the genus Chlamydomonas. Compounds 1 and 5 investigated for the first time in the activity of immunosuppressivity and 6 may come to serve as the most important marker in broad-spectrum activities of the secondary metabolites identified from C. sp. KSF108.

Chemical Constituents from the Aerial Parts of Artemisia capillaris Thunb. and Their Anti-allergic and Anti-inflammatory Effects

Artemisia capillaris Thunb. (Compositae) is a traditional medicinal plant with various pharmacological activities. To elucidate new anti-allergic and anti-inflammatory constituents, the aerial parts of A. capillaries were investigated to afford a new compound, (6E,8E)-6-methylundeca-6,8-diene-2,5,10-trione (17) together with 19 known compounds (1 - 16, 18 - 20). The structures of these compounds were determined by extensive spectroscopic analyses including 1D, 2D NMR, HREIMS, and optical rotation [α]D. The absolute configuration of compound 2 was determined to be S form for the first time. All isolates (1 - 20) were tested their inhibitory effects on interleukin 2 (IL-2) expression in T cells and NO production in lipopolysaccharide (LPS)-stimulated RAW246.7. Among them, compounds 10, 11, 19, and 20 reduced IL-2 expression in a dose-dependent manner. In addition, compound 10 also inhibited NO production with an IC50 value of 37.3 ± 0.4 μM.

Anti-inflammatory and Immunosuppressive Effects of Panax notoginseng

Here, we designed to examine the anti-inflammatory effects on RAW264.7 cells and the immunosuppressive effects by evaluating interleukin-2 (IL-2) production in Jurkat T cells using a MeOH extract of Panax notoginseng roots. The results showed that the MeOH extract inhibited the synthesis of nitric oxide (NO) in a dose-dependent manner (IC₅₀ value of 7.08 µg/mL) and displayed effects on T cell activation at a concentration of 400 µg/mL. In efforts to identify the potent compounds, bioactivity-guided fractionation of the MeOH extract and chemical investigation of its active CH₂Cl₂-, EtOAc-, and butanol-soluble fractions led to the successful isolation and identification of eleven compounds, including two polyacetylenes (1, 2), a steroid saponin (3), seven dammarane-type ginsenosides (4 – 10), and an oleanane-type ginsenoside (11). Among them, compound 11 was isolated from this plant for the first time. Compound 2 exhibited potent inhibitory effects on NO synthesis and an immunosuppressive effect with IC₅₀ values of 2.28 and 65.57 µM, respectively.

Cytotoxic Lactones from the Pericarps of Litsea japonica

From the pericarps of Litsea japonica (Thunb.) Jussieu, eighteen butanolide derivatives (1 – 18) were evaluated for their cytotoxic activity against HeLa, HL-60, and MCF-7 cells. Compounds 1 – 9 with 2-alkylidene-3-hydroxy-4-methylbutanolides structure exhibited cytotoxic activities against cancer-cell lines. Among them, compound 8 (litsenolide D₂) exhibited the most potent cytotoxicity against the tested cell lines, including HeLa, HL-60, and MCF-7, with IC₅₀ values of 17.6 ± 1.3, 4.2 ± 0.2, and 12.8 ± 0.0 µM, respectively. Compound 8 induced apoptosis in a dose-dependent manner. Annexin V/Propidium Iodide (PI) double staining confirmed that 8 effectively induced apoptosis in MCF-7 cells. To the best of our knowledge, we have reported cytotoxic activity of butanolides from L. japonica against these cancer-cell lines for the first time.

Cytotoxic Triterpenoids from the Fruits of Ligustrum japonicum

Medicinal plants are potential sources of anticancer agents screening. A large number of phytochemicals, including triterpenoids, have been reported to have significant cytotoxic effects on cancer cells. From the fruits of Ligustrum japonicum Thunb., thirteen triterpenoids (1 – 13) were isolated and evaluated for their cytotoxic activity against Hela and HL-60 cells. As results, 8 (oleanolic acid) showed significant effects on Hela with IC50 values of 5.5 µM, and moderate effects on HL-60 cells with IC₅₀ values of 55.9 µM. Meanwhile, 10 (oleanderic acid) and 11 (3β-acetoxy-urs-12-en-28-oic acid) exhibited moderate inhibitory effects on Hela with IC₅₀ value of 55.0 and 68.8 µM, respectively. Moreover, 10 showed cytotoxic effect on HL-60 cell line with IC₅₀ value of 63.9 µM. To our knowledge, this is the first report that oleanderic acid was isolated from L. japonicum and investigated in cytotoxic effects on Hela and HL-60 cells.