Lanostane Triterpenoids from the Mushroom <i>Naematoloma fasciculare</i>

In our continuing search for structurally interesting and bioactive metabolites from Korean wild mushrooms, bioassay-guided fractionation and a chemical investigation of the MeOH extracts of the fruiting bodies of the mushroom <i>Naematoloma fasciculare</i> resulted in the isolation of four new lanostane triterpenoids (<b>1</b>–<b>4</b>), together with 11 known compounds (<b>5</b>–<b>15</b>). The structures of <b>1</b>–<b>5</b> were determined by a combination of 1D and 2D NMR and HRMS. The absolute configuration of the 3-hydroxy-3-methylglutaryl group as a side chain in <b>1</b> and <b>2</b> was determined by the alkaline methanolysis method. The full NMR data assignment of the known compound fasciculol G (<b>5</b>) is reported for the first time. Compounds <b>1</b>–<b>15</b> were tested for their antiproliferative activities against four human cancer cell lines (A549, SK-OV-3, SK-MEL-2, and HCT-15) and evaluated for their inhibitory effects on nitric oxide production in a lipopolysaccharide-activated murine microglial cell line

Bioactive Lignans from the Rhizomes of <i>Acorus gramineus</i>

As a part of our ongoing search for bioactive constituents from natural Korean sources, the investigation of rhizomes of <i>Acorus gramineus</i> afforded five new lignans, named ligraminols A–E (<b>1</b>–<b>5</b>), together with seven known ones (<b>6</b>–<b>12</b>). The structures of <b>1</b>–<b>5</b> were determined by a combination of 1D and 2D NMR, HRMS, CD, and enzymatic hydrolysis. Compounds <b>1</b>–<b>12</b> were tested for their antiproliferative activities toward a panel of human-derived normal and cancer cell lines. Moreover, compounds <b>1</b>–<b>12</b> were evaluated for their inhibitory activities on nitric oxide production in an activated murine microglial cell line

Identification of Antitumor Lignans from the Seeds of Morning Glory (<i>Pharbitis nil</i>)

In the search for antitumor compounds from Korean natural resources, activity-guided fractionation and purification processes were used on seeds of morning glory (<i>Pharbitis nil</i>). Air-dried <i>P. nil</i> seeds were extracted with ethanol and separated into <i>n</i>-hexane, chloroform, ethyl acetate, and <i>n</i>-butanol. Four new lignans, pharbilignans A–D (<b>1</b>–<b>4</b>) were isolated from the most active ethyl acetate fraction of the ethanol extract. Their structures were characterized on the basis of spectroscopic methods, including one- and two-dimensional nuclear magnetic resonance (NMR) techniques, high resolution mass spectrometry (HRMS), and circular dichroism (CD) spectroscopy. The cytotoxic activities of the isolates (<b>1</b>–<b>4</b>) were evaluated by determining their inhibitory effects on four human tumor cell lines (A549, SK-OV-3, SK-MEL-2, and HCT15) using a sulforhodamine B (SRB) bioassay. Pharbilignan C (<b>3</b>) showed potent cytotoxicity against A549, SK-OV-3, SK-MEL-2, and HCT-15 cell lines with IC₅₀ values of 1.42, 0.16, 0.20, and 0.14 μM, respectively. On the basis of the expanded understanding that inflammation is a crucial cause in tumor progress, we also evaluated anti-inflammatory activity of the isolates (<b>1</b>–<b>4</b>). Pharbilignan C (<b>3</b>) strongly inhibited nitric oxide (NO) production in the lipopolysaccharide (LPS)-activated BV-2 microglia cell line with an IC₅₀ value of 12.8 μM

Creation of Resveratrol-Enriched Rice for the Treatment of Metabolic Syndrome and Related Diseases

<div><p>Resveratrol has been clinically shown to possess a number of human health benefits. As a result, many attempts have been made to engineer resveratrol production in major cereal grains but have been largely unsuccessful. In this study, we report the creation of a transgenic rice plant that accumulates 1.9 µg resveratrol/g in its grain, surpassing the previously reported anti-metabolic syndrome activity of resveratrol through a synergistic interaction between the transgenic resveratrol and the endogenous properties of the rice. Consumption of our transgenic resveratrol-enriched rice significantly improved all aspects of metabolic syndrome and related diseases in animals fed a high-fat diet. Compared with the control animals, the resveratrol-enriched rice reduced body weight, blood glucose, triglycerides, total cholesterol, and LDL-cholesterol by 24.7%, 22%, 37.4%, 27%, and 59.6%, respectively. The resveratrol-enriched rice from our study may thus provide a safe and convenient means of preventing metabolic syndrome and related diseases without major lifestyle changes or the need for daily medications. These results also suggest that future transgenic plants could be improved if the synergistic interactions of the transgene with endogenous traits of the plant are considered in the experimental design.</p> </div

Molecular characterization of transgenic rice lines expressing <i>AhSTS1</i>.

<p>(A) Southern blot analysis. Genomic DNA in lanes P and RS1 to RS22 were digested with <i>Bam</i>HI (specific to the T-DNA region). The arrow indicates the fragment (1.2 kb) hybridized with the <i>AhSTS1</i> cDNA probe. P, pSB2220 vector; N, non-transgenic wild-type Dongjin; lanes RS1 - RS22, representative transgenic Dongjin lines out of 129 T₁ samples. (B) RT-PCR analysis. Total RNA from leaf samples of the same lines as in (A) was analyzed. <i>OsUBQ5</i> was included as a PCR control.</p

The effects of the resveratrol-enriched rice on blood lipid and glucose levels.

<p>The values represent the means ± SEM (n = 16). CTL, mice fed a HFD (D12451); Resv, mice fed a HFD supplemented with resveratrol; DJ, mice fed a HFD in which the corn starch and sucrose were replaced with Dongjin rice; RS18-half, mice fed a HFD in which half of the corn starch and sucrose were replaced with the resveratrol-enriched rice; RS18, mice fed a HFD in which the corn starch and sucrose were replaced with the resveratrol-enriched rice. Values in a column with a superscripted letter indicate statistical significance as analyzed by an unpaired Student’s t-test;</p>a<p>p<0.05 compared with CTL;</p>b<p>p<0.01 compared with CTL;</p>c<p>p<0.05 compared with DJ;</p>d<p>p<0.01 compared with DJ.</p

Measurement of resveratrol-specific glucosyltransferase activity in rice leaves and grains.

<p>WT, wild-type Dongjin rice; RS18, <i>AhSTS1</i> transgenic Dongjin rice line. Remarkably high resveratrol-specific glucosyltransferase activity was found only in the leaves of the transgenic rice line RS18.</p