Jin Cheol Kim

Alkaloids from Chelidonium majus and their inhibitory effects on LPS-induced NO production in RAW264.7 cells.

A new alkaloid, methyl 2-(7,8-dihydrosanguinarine-8-yl)acetate (1), together with six known alkaloids, stylopine (2), protopine (3), norchelidonine (4), chelidonine (5), berberine (6), and 8-hydroxydihydrosanguinarine (7), were isolated from Chelidonium majus. Their chemical structures were primarily established using 1D and 2D NMR techniques and mass spectrometry. The anti-inflammatory activity of the isolates was examined for their inhibitory effects on LPS-induced NO production in macrophage RAW264.7 cells. Among them, compounds 5 and 7 showed strong inhibitory activities toward the LPS-induced NO production in macrophage RAW264.7 cells with IC(50) values of 7.3 and 4.5 μM, respectively. In addition, compounds 5 and 7 inhibited the inductions of COX-2 and iNOS mRNA in dose-dependent manners, indicating that these compounds attenuated the syntheses of these transcripts at the transcriptional level.

Steroids and triterpenes from the fruit bodies of Ganoderma lucidum and their anti-complement activity.

To determine the anti-complement activity of natural triterpenes, chromatographic separation of the EtOAc-soluble fraction from the fruiting body of Ganoderma lucidum led to the isolation of three steroids and five triterpenoids. They were identified as ergosterol peroxide (1), ergosterol (2), genoderic acid Sz (3), stella sterol (4), ganoderic aic C1 (5), ganoderic acid A (6), methyl ganoderate A (7), and lucidenic acid A (8) based on spectroscopic evidence and physicochemical properties. These compounds were examined for their anti-complement activity against the classical pathway of the complement system. Compounds 2 and 3 showed potent anti-complement activity with IC50 values of 52.0 and 44.6 µM, respectively. Compound 1 exhibited significant inhibitory activity with an IC50 value of 126.8 µM, whereas compounds 4–8 were inactive. Our findings suggested that in addition to the ketone group at C-3, the Δ7(8), Δ9(11)-lanostadiene type triterpene also plays an important role in inhibiting the hemolytic activity of human serum against erythrocytes.

Homoisoflavonoid derivatives from the roots of Ophiopogon japonicus and their in vitro anti-inflammation activity.

Three new homoisoflavonoids (1-3) were isolated from the roots of Ophiopogon japonicus (Liliaceae). The structures of new metabolites were determined on the basis of spectroscopic analyses including 2D NMR. The anti-inflammatory activities of new compounds (1-3) were investigated by their effects on the release of the inflammatory chemokine eotaxin, stimulated by IL-4 and the combination of IL-4 and TNF-alpha in BEAS-2B cells, which mimics the in vivo conditions in bronchial allergic asthma.

Oleanane-Type Triterpenoids from Aceriphyllum rossii and Their Cytotoxic Activity

The hexane-soluble fraction of the roots of Aceriphyllum rossii was used to isolate seven new oleanane-type triterpenoids, aceriphyllic acids C-I (1-7), together with seven known triterpenoids. The structures of aceriphyllic acids C-I were determined as 3alpha-hydroxyolean-12-en-23,29-dioic acid (1), 3beta-hydroxyolean-12-en-23,29-dioic acid (2), 3beta,23-dihydroxyolean-12-en-29-oic acid (3), 3alpha-O-acetylolean-12-en-23,27-dioic acid (4), 3alpha-O-caffeoylolean-12-en-27-oic acid (5), 3alpha-O-acetylolean-12-en-23,29-dioic acid (6), and 3alpha-hydroxyolean-12-en-23-al-27-oic acid (7) by spectroscopic analyses. In the evaluation of the in vitro cytotoxicity of these compounds against the MCF-7 and LLC cancer cell lines, compounds 10 and 13 exhibited cytotoxic activity against the LLC cancer cell line with IC(50) values of 7.63 and 6.56 microM, respectively.

A novel gene, ROA, is required for normal morphogenesis and discharge of ascospores in Gibberella zeae.

ABSTRACT Head blight, caused by Gibberella zeae, is a significant disease among cereal crops, including wheat, barley, and rice, due to contamination of grain with mycotoxins. G. zeae is spread by ascospores forcibly discharged from sexual fruiting bodies forming on crop residues. In this study, we characterized a novel gene, ROA, which is required for normal sexual development. Deletion of ROA (Δroa) resulted in an abnormal size and shape of asci and ascospores but did not affect vegetative growth. The Δroa mutation triggered round ascospores and insufficient cell division after spore delimitation. The asci of the Δroa strain discharged fewer ascospores from the perithecia but achieved a greater dispersal distance than those of the wild-type strain. Turgor pressure within the asci was calculated through the analysis of osmolytes in the epiplasmic fluid. Deletion of the ROA gene appeared to increase turgor pressure in the mutant asci. The higher turgor pressure of the Δroa mutant asci and the mutant spore shape contributed to the longer distance dispersal. When the Δroa mutant was outcrossed with a Δmat1-2 mutant, a strain that contains a green fluorescence protein (GFP) marker in place of the MAT1-2 gene, unusual phenotypic segregation occurred. The ratio of GFP to non-GFP segregation was 1:1; however, all eight spores had the same shape. Taken together, the results of this study suggest that ROA plays multiple roles in maintaining the proper morphology and discharge of ascospores in G. zeae.

Protein tyrosine phosphatase 1B inhibitory by dammaranes from Vietnamese Giao-Co-Lam tea.

ETHNOPHARMACOLOGICAL RELEVANCEnGynostemma pentaphyllum (Thunb.) tea was used in Vietnamese folk medicine as anti-diabetic agent.nnnAIM OF THE STUDYnThis study was aimed to investigate the inhibitory activities of fractions and constituents isolated from Gynostemma pentaphyllum on protein tyrosine phosphatase 1B (PTP1B) since it has been proposed as a treatment therapy for type 2 diabetes and obesity.nnnMATERIALS AND METHODSnThe 70% EtOH extract, CHCl3 fraction, EtOAc fraction, BuOH fraction, and seven isolated dammarane triterpenes were evaluated for their inhibitory activity in protein phosphatase enzymes (PTP1B and VHR).nnnRESULTSnCHCl3-soluble fraction showed a dose-dependent inhibitory activity of the PTP1B enzyme with the IC50 value of 30.5 microg/mL. Among seven tested compounds, compounds 6 showed the most potent PTP1B inhibitory activity with IC50 value of 5.3+/-0.4 microM compared to a range 15.7-28.5 microM for the other six compounds. The inhibition mode of 6 was competitive toward p-NPP with a K(i) value of 2.8 microM.nnnCONCLUSIONnThese study results suggested that the PTP1B inhibitory activity of these dammaranes may enable this plant to play an important role in the treatment of diabetes.

Phenolic glycosides from Alangium salviifolium leaves with inhibitory activity on LPS-induced NO, PGE2, and TNF-α production

Three new phenolic glycosides, salviifosides A-C (13), and three known compounds salicin (4), kaempferol (5), and kaempferol 3-O-beta-d-glucopyranoside (6) were isolated from the leaves of Alangium salviifolium (L.f.) Wangerin (Alangiaceae). The structures of the new metabolites were determined on the basic of spectroscopic analyses including two dimensional NMR. The anti-inflammatory activities of new compounds (1-3) were investigated on lipopolysaccharide (LPS)-induced murine macrophage cells line, RAW 264.7. Salviifoside B (2) potentially inhibits the productions of nitric oxide (NO), prostaglandin E(2) (PGE(2)), and tumor necrosis factor-alpha (TNF-alpha).

Phenolic Compounds from Caesalpinia sappan Heartwood and Their Anti-inflammatory Activity

Four new phenolic compounds, caesalpiniaphenols A-D (1-4), together with eight known compounds were isolated from Caesalpinia sappan heartwood. The chemical structures were established mainly by NMR, MS, ECD, and Moshers method. Compounds 4, 5, and 7 showed weak inhibitory activity against the LPS-induced NO production in macrophage RAW264.7 cells with IC(50) values of 12.2, 3.5, and 5.7 μM, respectively.

Triterpenoids and a sterol from the stem-bark of Styrax japonica and their protein tyrosine phosphatase 1B inhibitory activities

Five pentacyclic triterpenoids (1–5) and a sterol (6) were isolated from the stem‐bark of Styrax japonica. The six compounds, 1–6, were determined to be 3β‐acetoxy‐28‐hydroxyolean‐12‐ene (1), 3β‐acetoxyolean‐12‐en‐28‐acid (2), 3β‐acetoxyolean‐12‐en‐28‐aldehyde (3), 3β‐acetoxy‐17β‐hydroxy‐28‐norolean‐12‐ene (4), taraxerol (5) and stigmasterol (6), respectively, by spectroscopic means, including the 2D‐NMR technique. Compound 4 is a newly discovered natural compound. The protein tyrosine phosphatase 1B (PTP1B) inhibitory activities of the isolated compounds (1–6) were determined in vitro. Among the isolated compounds, 3β‐acetoxyolean‐12‐en‐28‐acid (2) and 3β‐acetoxyolean‐12‐en‐28‐aldehyde (3) had the most potent inhibitory PTP1B activity, with IC50 values of 7.8 and 9.3 µm, respectively. Copyright

Anticomplementary activity of triterpenoids from the whole plant of Aceriphyllum rossii against the classical pathway.

To provide a better understanding of the anti-complement activity of triterpenoids, seven unusual pentacyclic triterpenoids bearing a carboxyl group at C-27 were evaluated for their anticomplement activities against the classical pathway of the complement system. The triterpenoids were isolated from the whole plant of Aceriphyllum rossii of the family Saxifragaceae and were determined to be 3alpha,23-isopropylidenedioxyolean-12-en-27-oic acid (1), 3-oxoolean-12-en-27-oic acid (2), 3alpha-hydroxyolean-12-en-27-oic acid (3), beta-peltoboykinolic acid (4), 3alpha,23-diacetoxyolean-12-en-27-oic acid (5), 23-hydroxy-3-oxoolean-12-en-27-oic acid (6) and aceriphyllic acid A ( 7). Among them, compounds 2, 3, and 5 showed significant anticomplement activity on the classical pathway with IC (50) values of 71.4, 98.5, and 180.7 microM, respectively, whereas compounds 1, 4, 6, and 7 were inactive. Our findings suggest that both the ketone at C-3 and the methyl at C-23 in the oleanane triterpenoids with a carboxyl group at C-27 are important for the anticomplement activity against the classical pathway.