Quinic acid esters from Erycibe obtusifolia with antioxidant and tyrosinase inhibitory activities.

AbstractA new quinic acid derivative, 3-O-syringoylquinic acid methyl ester (1), along with eight known quinic acid derivatives (2-9), three coumarins (10-12), one phenylpropanoid (13), three feruloyltyramine derivatives (14-16), one lignan (17) and two isoflavones (18-19) were isolated from an ethyl acetate-soluble fraction of the roots and stems of Erycibe obtusifolia. The structure was elucidated on the basis of spectroscopic methods such as 1D and 2D-NMR, including HR-ESI-MS spectrometry. All of these compounds were investigated for their 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and inhibitory effects on mushroom tyrosinase. Compounds 2-9, quinic acid derivatives with caffeoyl moiety, showed significant DPPH radical scavenging activity. Moreover, compounds 2 and 5-10 showed weak mushroom tyrosinase inhibitory effects.

Molecular Identification of Necrophagous Dermestes Species in South Korea Using Cytochrome c Oxidase Subunit I Nucleotide Sequences (Genus Dermestes).

Species identification of necrophagous insects found on a dead body is an essential key in applying medicolegal entomology to the estimation of postmortem interval (PMI). Due to limited morphological identification of insect evidence, several studies have identified species using molecular information such as DNA markers. While considerable cytochrome c oxidase subunit I (COI) gene sequence data of necrophagous fly species have been collected and annotated, those of necrophagous beetle species have not. Since necrophagous beetles such as Dermestes species have a larval period longer than that of flies, beetles are useful in even the late decomposition phase in estimating minimum PMI. To obtain the full-length COI gene sequences of six Dermestes species collected from South Korea, we designed primers for polymerase chain reaction amplification and sequencing. The obtained full COI nucleotide sequences were used for performing phylogenic analysis and comparison with previously reported sequences. The results demonstrated that the COI gene sequences could be used to identify forensically important Dermestes species in South Korea.

Pyranoflavanones and Pyranochalcones from the Fruits of Amomum tsao-ko.

Eight new geranylated and farnesylated pyranoflavanones (1-8) and two new farnesylated pyranochalcones (9 and 10) were isolated from the methanolic extract of the fruits of Amomum tsao-ko. Their structures were elucidated by extensive analysis of the 1D and 2D NMR spectra and from the HRESIMS, combined with experimental ECD data. All compounds were evaluated for their inhibitory effects on the nitric oxide production against lipopolysaccharide-induced RAW 264.7 macrophages and exhibited IC50 values ranging from 10.6 to 41.5 µM.

SNP Typing Using Multiplex Real-Time PCR Assay for Species Identification of Forensically Important Blowflies and Fleshflies Collected in South Korea (Diptera: Calliphoridae and Sarcophagidae).

Medicolegal entomology-a subfield of forensic entomology-is mainly used in medicolegal investigations to estimate the postmortem interval (PMI). The minimum PMI of a corpse invaded by necrophagous immature insects can be estimated because the PMI is near to or earlier than the oviposition time of the larvae that hatched and fed on the corpse. As the growth speeds of larvae differ depending on temperature and species, species-specific growth data are used to estimate the minimum PMI. While morphological identification of adult necrophagous flies can be done by a well-trained entomologist, identification of larvae is relatively difficult. Larvae can only be identified up to the family level and developmental stage by observing the posterior spiracles. For these reasons, the molecular biology method of DNA barcoding has been developed. DNA barcoding that targets the mitochondrial cytochrome c oxidase subunit I (COI) gene is commonly used. COI sequences are currently acquired using polymerase chain reaction (PCR) and Sanger sequencing, which are too time-consuming and complex for practical use in medicolegal investigations. To compensate for these limitations and facilitate the use of entomology for medicolegal investigation, we designed a multiplex real-time PCR system to identify nineteen forensically important species of Calliphoridae and Sarcophagidae flies collected in South Korea. In contrast to the Sanger nucleotide sequencing process, this technology only requires a one-step real-time PCR with melt curve analysis of amplicons generated by primers targeting species-specific single nucleotide polymorphisms (SNPs). Multiplex real-time PCR was performed for twelve species of Calliphoridae (four reactions) and for seven species of Sarcophagidae (three reactions). This assay is expected to make it easier and faster for investigating authorities to identify major species of necrophagous flies at beginning of investigation and to increase the utilization of entomological evidence in forensic investigations.

Lathyrane-Type Diterpenoids from the Seeds of Euphorbia lathyris L. with Inhibitory Effects on NO Production in RAW 264.7 Cells.

Bioactivity-guided fractionation of the methanolic extract from the seeds of Euphorbia lathyris led to the isolation of 18 lathyrane-type diterpenoids including a new one, Euphorbia factor L29 (1). Their chemical structures were elucidated by extensive NMR spectroscopic data including 2D-NMR and HR-ESI-MS as well as CD data. All isolates (1 - 18) were found to inhibit the nitric oxide production in LPS-induced RAW 264.7 macrophages, with their IC50 values in the range of 11.2 - 52.2 µm.

Dimeric- and trimeric sesquiterpenes from the flower of Inula japonica.

An undescribed unusual sesquiterpene trimer and three sesquiterpene dimers were isolated from the flowers of Inula japonica. Their structures were elucidated by extensive analysis of 1D and 2D NMR spectroscopic data as well as HRESIMS data. Inulajaponicolide A has an undescribed carbon skeleton comprising of one xanthanolide and two guaianolide units with the linkage mode of C-11/C-3' and C-11'/C-1'' via a Diels-Alder cycloaddition reaction. Inulajaponicolides C and D exhibited moderate cytotoxic activity against A 549 and NCI-H460 human cancer cell lines with IC50 values ranging from 8.5 to 17.8 µM. Inulajaponicolides A-D and lineariifolianoid A possessed significant inhibitory potency against nitric oxide production in LPS-induced RAW264.7 cells with IC50 values ranging from 1.0 to 4.1 µM.

Nitric oxide inhibitory constituents from Siegesbeckia pubescens.

Two new sesquiterpenoids (1 and 2) and a new ent-pimarane type diterpenoid (3), together with eighteen known compounds (4-21), were isolated from the whole plants of Siegesbeckia pubescens. The structures of the new compounds were determined on the basis of 1D-, 2D NMR and HRESIMS data. All compounds were evaluated for their inhibitory effects on LPS-induced nitric oxide production in RAW 264.7 macrophages. Of these, highly oxygenated germacrane type sesquiterpenoids (1-2 and 13-14) showed significant inhibitory effects with IC50 values ranging from 3.9 to 16.8 µM.

Phenolic amides from Tribulus terrestris and their inhibitory effects on nitric oxide production in RAW 264.7 cells.

A new phenolic amide, named cis-terrestriamide (7), together with ten known compounds (1-6, 8-11), were isolated from the methanolic extract of the fruits of Tribulus terrestris. The structure of 7 was elucidated on the basis of extensive analyses of 1D and 2D nuclear magnetic resonance spectroscopic and high resolution mass spectrometry data. Compounds 1, 2, 5, 6, 8, 9, and 11 exhibited inhibitory effects on the lipopolysaccharide-stimulated nitric oxide production in RAW 264.7 cells, with IC50 values of 18.7-49.4 µM.

Chemical Constituents Isolated from Bletilla striata and Their Inhibitory Effects on Nitric Oxide Production in RAW 264.7 Cells.

Bioassay-guided fractionation of the MeOH extract of the tubers of Bletilla striata led to the isolation of two new C-methylated flavan-3-ols, bletillanols A (1) and B (2), along with ten known compounds (3 - 12). Their structures were determined by using extensive spectroscopic analysis including 1D-, 2D-NMR, and circular dichroism data. All of the isolated compounds were tested for their inhibitory potential on the nitric oxide generation in LPS-stimulated RAW 264.7 cells.

Dimeric sesquiterpene and thiophenes from the roots of Echinops latifolius.

Phytochemical investigation of the roots of Echinops latifolius led to the isolation of a new carbon skeleton dimeric sesquiterpene (1) and a new thiophene (2), along with six known compounds (3-8). Their structures and relative stereochemistry were elucidated by spectroscopic and spectrometric methods (1H and 13C NMR, COSY, HSQC, HMBC, ROESY, and MS). All isolates were evaluated for their inhibition of LPS-induced NO production in RAW 264.7 cells. Compounds 4 and 5 exhibited the most potent inhibitory effects on NO production.

Effect of Korean Red Ginseng extraction conditions on antioxidant activity, extraction yield, and ginsenoside Rg1 and phenolic content: optimization using response surface methodology.

BACKGROUND: Extraction conditions greatly affect composition, as well as biological activity. Therefore, optimization is essential for maximum efficacy. METHODS: Korean Red Ginseng (KRG) was extracted under different conditions and antioxidant activity, extraction yield, and ginsenoside Rg1 and phenolic content evaluated. Optimized extraction conditions were suggested using response surface methodology for maximum antioxidant activity and extraction yield. RESULTS: Analysis of KRG extraction conditions using response surface methodology showed a good fit of experimental data as demonstrated by regression analysis. Among extraction factors, such as extraction solvent and extraction time and temperature, ethanol concentration greatly affected antioxidant activity, extraction yield, and ginsenoside Rg1 and phenolic content. The optimal conditions for maximum antioxidant activity and extraction yield were an ethanol concentration of 48.8%, an extraction time 73.3 min, and an extraction temperature of 90°C. The antioxidant activity and extraction yield under optimal conditions were 43.7% and 23.2% of dried KRG, respectively. CONCLUSION: Ethanol concentration is an important extraction factor for KRG antioxidant activity and extraction yield. Optimized extraction conditions provide useful economic advantages in KRG development for functional products.

Flavonol glycosides from the aerial parts of Gynostemma pentaphyllum and their antioxidant activity.

The phytochemical investigation of the aerial parts of Gynostemma pentaphyllum led to the isolation of a new flavonol glycoside, gynopentaphylloside (1), along with seven known compounds (2-8). The structure of the new compound was determined on the basis of 1D, 2D NMR and HRESIMS data as well as acid hydrolysis. The antioxidant activity of the isolates was evaluated by a 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay.

Jatrophane and ingenane-type diterpenoids from Euphorbia kansui inhibit the LPS-induced NO production in RAW 264.7 cells.

Bioactivity-guided fractionation of the MeOH extract from the roots of Euphorbia kansui resulted in the isolation of two new jatrophane-type diterpenoids, kanesulones A (1) and B (2), together with six known jatrophane-type diterpenoids (3-8) and ten known ingenane-type diterpenoids (9-18). Their chemical structures were elucidated on the basis of spectroscopic data interpretation, especially 1D and 2D NMR such as HMQC, HMBC, COSY and NOESY, and HRESIMS data as well as CD analysis. Compounds 1-8 and 11-18 exhibited the inhibitory effects on LPS-induced nitric oxide production with IC50 values ranging from 0.7 to 46.5µM in RAW 264.7 macrophages.

Sesquiterpenes from Inula japonica with Inhibitory Effects on Nitric Oxide Production in Murine Macrophage RAW 264.7 Cells.

Eight new sesquiterpenes (1-8), along with seven known sesquiterpenes (9-15), were isolated from a methanol extract of the flowers of Inula japonica. Their structures were elucidated by a combination of 1D and 2D NMR spectroscopic and HRESIMS data. All of isolates were evaluated for their inhibitory effects on nitric oxide production in LPS-induced RAW 264.7 cells, with their IC50 values ranging from 1.9 to 15.4 µM.

Sesquiterpenoids from Tussilago farfara inhibit LPS-induced nitric oxide production in macrophage RAW 264.7 cells.

A new oplopane-type sesquiterpenoid tussilagofarin (1) and a new chromone tussilagofarol (2), along with 18 known compounds 3-20, were isolated from the flower buds of Tussilago farfara. The structures of the new compounds were elucidated on the basis of 1D and 2D NMR and HRESIMS data. Of the isolated compounds, oplopane- and bisabolane-type sesquterpenoids 1, 8-12, 15, and 16 were found to inhibit nitric oxide production in LPS-induced RAW 264.7 cells with IC50 values of 3.5-28.5 µM.

Diterpenoids from the Roots of Euphorbia fischeriana with Inhibitory Effects on Nitric Oxide Production.

Bioactivity-guided isolation of a methanolic extract of Euphorbia fischeriana led to the isolation of four new abietane-type diterpenoids, fischeriolides A-D (1-4), together with 11 known diterpenoids. Their structures were elucidated based on the interpretation of 1D and 2D NMR spectroscopic and HRESIMS data. The absolute configuration of compound 3 was determined by single-crystal X-ray diffraction analysis and electronic circular dichroism methods. Compounds 5-9 exhibited inhibitory effects on LPS-induced nitric oxide production in RAW 264.7 macrophages with IC50 values in the range 4.9-12.6 µM.

neo-Clerodane Diterpenoids from Scutellaria barbata and Their Inhibitory Effects on LPS-Induced Nitric Oxide Production.

Three new neo-clerodane diterpenoids (1-3) along with 12 known compounds (4-15) were isolated from a methanol extract of the aerial parts of Scutellaria barbata. The structures of 1-3 were determined by interpretation of their 1D and 2D NMR spectroscopic data as well as HRESIMS values. All isolated compounds were tested for their inhibitory effects on LPS-induced nitric oxide production in RAW 264.7 macrophages. Compounds 1-4, 7, and 10-12 were found to inhibit nitric oxide production with IC50 values ranging from 20.2 to 35.6 µM.

Isolation and Characterization of Dammarane-Type Saponins from Gynostemma pentaphyllum and Their Inhibitory Effects on IL-6-Induced STAT3 Activation.

Five new dammarane-type saponins, gypenosides GD1-GD5 (1-5), along with six known saponins (6-11), were isolated from the aerial parts of Gynostemma pentaphyllum using various chromatographic methods. Their structures were elucidated by a combination of spectroscopic and spectrometric data, including 1D and 2D NMR and HRESIMS. All isolates were tested for their inhibitory effects on IL-6-induced STAT3 promoter activity in Hep3B cells. Compounds 1, 9, and 11 displayed potent inhibitory effects, with IC50 values ranging from 0.27 to 0.59 µM.