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Two new guaiane-type sesquiterpenes ( 1 and 2 ) together with eight related sesquiterpenoidal constituents ( 3 – 10 ) were isolated from the whole extract of Youngia japonica . The chemical structures of 1 – 10 were established by spectroscopic analyses as 4- epi -isolipidiol ( 1 ), 4′- p -hydroxyphenylacetyl crepiside E ( 2 ), isolipidiol ( 3 ), isoambeboin ( 4 ), grosheimin ( 5 ), annuionone D ( 6 ), loliolide ( 7 ), youngiajaponicoside A ( 8 ), crepiside H ( 9 ), and crepiside E ( 10 ), respectively. Among the isolated components, 5 exhibited a significant inhibitory effect on the proliferation of cultured human tumor cell lines (A549, SK-OV-3, SK-MEL-2, and HCT15).

Ultraviolet B (UVB) irradiation causes skin damage and inflammation by inducing the secretion of various cytokines, which are immune regulators produced by cells. To prevent skin inflammation, keratinocytes that have been irreversibly damaged by UVB must be eliminated through apoptosis. Ixeris dentata (I. dentata) (family Asteraceae) is a perennial medicinal herb indigenous to Korea. It is used in Korea, China and Japan to treat indigestion, pneumonia, diabetes, hepatitis, contusions and tumors. Guaiane-type sesquiterpene lactones were isolated from the whole extract of I. dentata. This led to the isolation of the anti-inflammatory sesquiterpene lactone compound tectroside (TES), which was tested on a human keratinocyte cell line. To determine the anti-inflammatory effects of TES, we examined its influence on UVB-induced pro-inflammatory cytokine production in human keratinocytes (HaCaT cells) by observing these cells in the presence or absence of TES. In the present study, pro-inflammatory cytokine production was determined by performing enzyme-linked immunosorbent assay, reverse transcription-polymerase chain reaction and western blot analysis to evaluate the activation of mitogen-activated protein kinases (MAPKs). TES inhibited UVB-induced production of the pro-inflammatory cytokines interleukin (IL)-6 and IL-8 in a dose-dependent manner. In addition, TES inhibited the expression of cyclooxygenase (COX)-2 and the phosphorylation of c-Jun NH2-terminal kinase (JNK) and extracellular signal-regulated kinase (ERK) MAPKs, suggesting that it inhibits the secretion of the pro-inflammatory cytokines IL-6 and IL-8 and COX-2 expression by blocking MAPK phosphorylation. These results suggest that TES can potentially protect against UVB-induced skin inflammation.

College of Pharmacy, Chungnam National University, Daejeon 305-764, KoreaReceived October 24, 2011, Accepted November 19, 2011Key Words : Amino acid-sesquiterpene lactone conjugates, Ixeris dentata, Asteraceae Ixeris dentata (Asteraceae) is a perennial herb which isused frequently as a Traditional Chinese Medicine for thetreatment of gastroenteric troubles, diabetes, pneumonia,hepatitis and tumor.

This study was conducted to assess the possibility of 5,8-dihydroxy-1,4-naphthoquinone (DHNQ) as a environmental friendly herbicide candidate. Foliar application of DHNQ showed excellent herbicidal effect to the 3 grasses and 5 broad-leaved weeds. Among them, Digitaria sanguinalis and Solanum nigrum were completely controlled by of DHNQ with main symptoms of desiccation or burndown within 24 hours. Aeschynomene indica was also sensitive to DHNQ treatment. All of the eight weed species were controlled by 90~100% at a concentration of . However, soil application of DHNQ to Digitaria sanguinalis did not show any herbicidal symptoms. DHNQ strongly inhibited KAPAS activities in vitro and the was . Cellular leakage from cucumber leaf squares treated with DHNQ increased depending on the concentrations increased from 6.25 to after 24 hours incubation with or without light. However, chlorophyll loss in cucumber leaf squares was negligible. Biotin supplements significantly rescued the inhibition of germination rate of Arabidopsis thaliana seeds previously inhibited by the DHNQ. According to above results, DHNQ is a good natural herbicide candidate having a new target KAPAS, which is involved in biotin biosynthesis pathway, with environmental friendly.

Graduate School of New Drug Discovery and Development, Chungnam National University, Daejeon 305-764, KoreaReceived July 30, 2014, Accepted August 29, 2014Key Words : Lycoris radiata, Amaryllidaceae alkaloids, Acetylcholinesterase inhibitionLycoris radiata (red spider lily) is a bulbous perennialplant in Amaryllidaceae widely distributed in Korea, Japanand China. It is commonly used as an ornamental flower orsometimes as an antidote in Traditional Chinese Medicine(TCM).

A genuine triterpenoid saponin, platyconic acid A (1) was isolated from the roots extract of Platycodon grandiflorum, together with five known saponins: deapioplatycoside E (2), platycoside E (3), platycodin D(3) (4), platycodin D(2) (5) and platycodin D (6). The structure of 1 was determined on the basis of spectral analysis and chemical evidence.

Natural marine products have recently become the focus of increased research interest, due to their potential pharmacological activities. Therefore, we have screened 50 varieties of marine seaweed and determined that the methanolic extracts from Plocamium telfairiae (PTE) exhibited a cytotoxic effect against HT-29 human colon carcinoma cells. In this study, we report on the cytotoxic activity and mechanism of PTE-induced apoptosis in HT-29 cells. The treatment of HT-29 cells with various PTE concentrations resulted in the inhibition of growth and the induction of apoptosis in a dose-dependent manner, as determined by the results of a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide reduction assay, a lactate dehydrogenase release assay, a morphological assay, and a colony formation assay. Interestingly, we also detected apoptotic bodies on Hoechst staining and attempted to determine whether the PTE-induced apoptosis involved the caspase pathway, using a caspase colorimetric assay. The activation of caspases-8, -9, -3, and -7 and the specific proteolytic cleavage of poly(ADP-ribose) polymerase were detected over the course of apoptosis induction. Our results showed that PTE may function as a chemopreventive and/or chemotherapeutic agent in colon carcinoma cells via the reduction of cell viability and the induction of apoptosis.

The antimicrobial substance from Pyrola japonica were extracted and isolated. Eighty percent ethanol extract of dried Pyrola japonica was fractionated to hexane, diethyl ether, ethyl acetate and aqueous layer. The hexane-soluble fraction showed the highest inhibitory activity against Bacillus subtilis. Moreover the hexane layer was fractionated into 5 groups by silica gel column chromatography. From the results, group No. 2 ( fractions) showed the highest antimicrobial activity. The group was re-separated to 10 fractions by preparative thin layer chromatography and the peak I as active fraction was isolated by HPLC.

Bakuchiol (1) is an unique prenylated phenolic meroterpene found exclusively in the seeds of Psoralea corylifolia L. P. corylifolia is an annual plant of the Leguminosae family and distributed over Southeast Asian countries. Numerous biological actions of the whole extract of the plant or purified constituents have been reported as antioxidant, antiinflammatory and antibacterial activities. Compound 1 has been introduced firstly to be isolated from the species by G. Mehta et al. and the chemical structure of 1 was fully determined including the absolute configuration of C-6 as (S)-chirality, even the total synthesis was accomplished in 1973. 1 is the main constituent of the species and reported to exert antidiabetic, antitumor effects, BACE-1 inhibitory activity, and hepatoprotective activities. In the previous study, we had reported that the seeds extract of P. corylifolia exhibited a marked inhibitory effect on the proliferation of cultured human tumor cell lines and the inhibitory effect was mainly ascribed to 1, a major component of the extract. As a trial for optimizing the chemical structure of 1 for improved antitumor activity, several analogues (2-8) of 1 were prepared according to the synthetic routes illustrated in Scheme 1. Briefly, 1 was treated with an equivalent amount of H2O2 and (NH4)2Ce(NO3)6 (ammonium cerium nitrate; CAN) in acetic acid to give 2. It seemed that the Δ double bond of 1 was oxidized to give a corresponding diol, which was further acetylated to produce 2. Compound 3 was prepared by the epoxidation of 1 with m-chloroperbenzoic acid in CH2Cl2 at 0 C. The treatment of

Notes DOI 10.5012/bkcs.2010.31.11.3448 A New Glycoside of Resveratrol Dimer from Stem Bark of Vitis vinifera Chun Whan Choi,†,‡ Yeon Hee Choi,† Mi-Ran Cha,†,‡ Dae Seok Yoo,†,‡ Young Sup Kim,† Gyu hwan Yon,† Sang Un Choi,† Young Ho Kim,‡,* and Shi Yong Ryu†,* †Korea Research Institute of Chemical Technology, Daejeon 305-606, Korea. *E-mail: syryu@krict.re.kr ‡College of Pharmacy Chungnam National University, Daejeon 305-764, Korea. *E-mail: yhk@cnu.ac.kr Received August 16, 2010, Accepted September 15, 2010

Pancreatic cancer cells are sometimes exposed to stressful microenvironments such as glucose deprivation, hypoxia, and starvation of other nutrients. These stresses, which are characteristic of poorly vascularized solid tumors, activate the unfolded protein response (UPR). The UPR is a stress-signaling pathway present in tumor cells that is associated with molecular chaperone GRP78. Induction of GRP78 has been found to increase cell survival and decrease apoptotic potential through genetic alterations. Thus GRP78 may represent a novel target in the development of anticancer drugs. Here we established a novel screening program to identify chaperone modulators that exhibit preferential cytotoxic activity in glucose-deprived pancreatic cancer cells. During the course of our screening, we isolated an active substance, Ponciri Fructus (PF), from an herbal medicine source and identified it as a down-regulator of GRP78. As expected, PF inhibited expression of the GRP78 protein under glucose-deprivation conditions in a dose-dependent manner. Furthermore, it induced selective cytotoxicity against glucose-deprived cancer cells; this effect was not observed under normal growth conditions. We also detected apoptotic bodies on Hoechst staining and attempted to determine whether PF-induced apoptosis involved caspase-3 activation. Our results suggest that the GRP78-inhibitory action of PF was dependent on strict hypoglycemic conditions and that it resulted in the selective death of glucose-deprived pancreatic cancer cells.

Colorectal cancer is the third most common cause of cancer-related deaths in the world. Surgical intervention followed by chemotherapy remains the primary approach to treatment since colon cancers remain refractory to most chemotherapeutic agents. Based on that, we established a program to screen natural products for cytotoxic activity, employing the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reduction assay system utilizing HT-29 human colon cancer cells. During the course of our screening, we found that the methanolic extract of silkworm droppings (SDME) has cytotoxic effects on HT-29 cells. In the present study, we investigated the possible mechanisms by which SDME exerts its antiproliferative activity in HT-29 cells. As expected, SDME inhibited growth of HT-29 cells in a dose-dependent manner as assessed by the MTT reduction assay, the lactate dehydrogenase release assay, and the colony formation assay. We also investigated whether the apoptotic effects induced by SDME involve the caspase pathway using the caspase colorimetric assay. Interestingly, caspase-9 and -3, but not caspase-8, were activated in response to SDME treatment. Taken together, these results clearly indicate that the induction of apoptosis by SDME involves a mitochondrial-mediated pathway and strongly suggest that SDME may potentially be a chemotherapeutic agent for human colon cancer.