Coreolanceolins A-E, New Flavanones from the Flowers of Coreopsis lanceolate, and Their Antioxidant and Anti-inflammatory Effects.

(1) Background: Many flavonoids derived from natural sources have been reported to exhibit antioxidant and anti-inflammatory effects. Our preliminary study suggested that Coreopsis lanceolata flowers (CLFs) include high flavonoid content; (2) Methods: CLFs were extracted in 80% (v/v) aqueous methanol and fractionated into ethyl acetate, n-butanol, and water fractions. Repeated column chromatographies for the organic fractions led to the isolation of seven flavanones. Quantitative analysis of the flavanones was carried out using reversed-phase high-performance liquid chromatography. All flavanones were evaluated for their antioxidant and pro-inflammatory inhibition effects; (3) Results: Spectroscopic analyses revealed the chemical structure of five new flavanones, coreolanceolins A-E, and two known ones. The content of the seven flavanones in extracts were determined from 0.8 ± 0.1 to 38.8 ± 0.3 mg/g. All flavanones showed radical scavenging activities (respectively 104.3 ± 1.9 to 20.5 ± 0.3 mg vitamin C equivalents (VCE)/100 mg and 1278.6 ± 26.8 to 325.6 ± 0.2 mg VCE/100 mg) in the DPPH and 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays and recovery activities in Caco-2 (59.7 to 41.1%), RAW264.7 (87.8 to 56.0%), and PC-12 (100.5 to 69.9%) cells against reactive oxygen species. Furthermore, all flavanones suppressed nitric oxide production (99.5% to 37.3%) and reduced iNOS and COX-2 expression in lipopolysaccharide-treated RAW 264.7 cells; (4) Conclusions: Five new and two known flavanones were isolated from CLF, and most of them showed high antioxidant and pro-inflammatory inhibition effects.

Flavonoids from Chionanthus retusus (Oleaceae) Flowers and Their Protective Effects against Glutamate-Induced Cell Toxicity in HT22 Cells.

The dried flowers of Chionanthus retusus were extracted with 80% MeOH, and the concentrate was divided into EtOAc, n-BuOH, and H2O fractions. Repeated SiO2, octadecyl SiO2 (ODS), and Sephadex LH-20 column chromatography of the EtOAc fraction led to the isolation of four flavonols (1-4), three flavones (5-7), four flavanonols (8-11), and one flavanone (12), which were identified based on extensive analysis of various spectroscopic data. Flavonoids 4-6 and 8-11 were isolated from the flowers of C. retusus for the first time in this study. Flavonoids 1, 2, 5, 6, 8, and 10-12 significantly inhibited NO production in RAW 264.7 cells stimulated by lipopolysaccharide (LPS) and glutamate-induced cell toxicity and effectively increased HO-1 protein expression in mouse hippocampal HT22 cells. Flavonoids with significant neuroprotective activity were also found to recover oxidative-stress-induced cell damage by increasing HO-1 protein expression. This article demonstrates that flavonoids from C. retusus flowers have significant potential as therapeutic materials in inflammation and neurodisease.

Synergistic Effect of Two Major Components of Malva verticillata in the Recovery of Alloxan-Damaged Pancreatic Islet Cells in Zebrafish.

Malva verticillata (Chinese mallow) has long been used in traditional medicines and herbal teas in Asia. The n-BuOH fraction (Fr) from M. verticillata promoted significant recovery of alloxan-damaged (AXD) pancreatic islets (PIs) in zebrafish (ZF). Two major components were isolated from M. verticillata through repeated-column chromatography. Based on several spectroscopic methods, including nuclear magnetic resonance (NMR), infrared spectroscopy (IR), and fast atom bombardment-mass spectrometry (FAB-MS), the chemical structures of compounds 1 and 2 were determined. In addition, the quantity of both compounds in the n-BuOH Fr was investigated through high-performance liquid chromatography (HPLC) and the quantities of compounds 1 and 2 in the n-BuOH Fr were determined to be 5.58% ± 0.16% and 2.85% ± 0.13%, respectively. The n-BuOH Fr, compounds 1 and 2, and the mixture of compounds 1 and 2 (MX, 1 and 2, the ratio of both compounds in n-BuOH Fr, 1.96:1) were evaluated for their ability to recover AXD PIs and for their KATP channel-blocking mechanism using diazoxide in ZF. The n-BuOH Fr (10 µg/mL) and compounds 1 and MX (1 µg/mL) exhibited a recovery effect on AXD PIs. The n-BuOH Fr (10 µg/mL) and MX (1 µg/mL) were also confirmed to be useful KATP channel activators. A synergistic effect of MX in the recovery of AXD PIs was first confirmed in ZF, and it was discovered that 2 acted as an insulin sensitivity activator that increased the activity of compound 1.

Lanceoleins A-G, hydroxychalcones, from the flowers of Coreopsis lanceolata and their chemopreventive effects against human colon cancer cells.

Seven new chalcones, lanceolein A-G (compounds 5 and 7-12), as well as five known chalcones (1-4 and 6), were isolated from the methanolic extract of Coreopsis lanceolata flowers. The chemical structures of 5 and 7-12 were determined on the basis of spectroscopic data interpretation. All compounds inhibited the production of nitrite oxide (NO) induced by LPS in RAW264.7 macrophage cells. Also, compounds 1-6 showed moderated cytotoxicity against human colon cancer cell lines, while compounds 7-12 hardly showed the cytotoxicity. Especially, compounds 2, 5, and 6 exhibited a little higher cytotoxicity on HCT15 cells, with IC50 values of 43.7 ±â€¯2.17 µM, 35.6 ±â€¯0.24 µM, and 47.9 ±â€¯1.18 µM, respectively. In the Tali assay, compounds 2 and 5 increased the numeral of apoptotic cells. These compounds also significantly promoted the expression of apoptotic proteins including PARP and caspase-3.

Glycerides isolated from the aerial parts of Malva verticillata cause immunomodulation effects via splenocyte function and NK anti-tumor activity.

A preliminary study revealed that a 10 µg/mL n-BuOH fraction of Malva verticillata aerial parts significantly enhanced splenocyte proliferation and induced significant enhancement of natural-killer (NK) cell activity against tumor cells (YAC-1). This study was initiated to identify the principal components that exhibited these activities, and four glycerides were isolated through repeated SiO2 and ODS column chromatography. Structures of compounds 1-4 were determined to be (2S)-1-O-palmitoyl glyceride, (2S)-1-O-stearoyl glyceride, (2S)-1-O-linolenoyl glyceride, and (2S)-1,2-di-O-linoleoyl glyceride, respectively. Compounds 1-3 showed potential immune-enhancing activity in murine splenocyte and natural-killer (NK) cells at 10 µM. In contrast, compound 4 showed weak activity, indicating the monoacyl glycerides (1-3) are more effective than diacyl glyceride (4). Also, the longer the carbon number of the fatty acid in monoacyl glyceride, the better the activity, and the monoacyl glyceride including an unsaturated fatty acid (3) is more effective than the glycerides including the saturated fatty acids (1-2).

Flavonoid 8-O-Glucuronides from the Aerial Parts of Malva verticillata and Their Recovery Effects on Alloxan-Induced Pancreatic Islets in Zebrafish.

Malva verticillata (Cluster mallow), a leafy vegetable that has been popular in East Asia for a long time, has also been used in herbal teas and medicines. The aqueous fraction of the aerial parts of Malva verticillata, exhibiting a very high quantity of flavonoids compared to the EtOAc and n-BuOH fractions, exhibited significant recovery effects on pancreatic islets damaged by alloxan in zebrafish larvae. Thus, the bioactive components responsible for this anti-diabetic activity were investigated. A new flavonoid glucuronide (1) and five known flavonoids were isolated from the aqueous fraction. Based on several spectroscopic methods, compound 1 was identified to be nortangeretin-8-O-ß-D-glucuronide, and was named malvaflavone A. The A-ring of compound 1 had a 5,6,7,8-tetrahydroxy moiety, which rarely occurs in plant systems. Also 8-O-glucuronide attached to the flavonoid moiety was rarely occurred in plant system. Compounds 1, 3, 4, and 6 significantly improved the pancreatic islet size in zebrafish at 0.1 µM, and compounds 1 and 6 were found to block ß-cell K⁺ channels in experiments with diazoxide. In ABTS, ORAC, and SOD assays, compounds 1-5 exhibited high anti-oxidant activities compared with quercetin and BHA (positive controls), indicating that the 8-O-glucuronide attached to the flavonoid moiety is a key structure for the expression of anti-oxidant activity. This is the first report of the isolation of compounds 1-6 from M. verticillata as well evaluated for anti-diabetic and anti-oxidant ativities.

Glycosyl glycerides from the aerial parts of Malva verticillata and their chemopreventive effects.

A new glycosyl glyceride (5) along with twelve known ones (1-4 and 6-13) including two sulfoquinovosyl glycerides (1 and 2) were isolated from the aerial parts of Malva verticillata. Based on several spectroscopic methods, compound 5 was identified to be (2S)-1-O-ß-d-galactopyranosyl-3-O-isostearoyl glyceride, and named malvaglycolipid A. Compounds 1 and 2 contained a unique sugar, (6-deoxy-6-sulfo)-α-d-glucopyranose, which very rarely occurs in natural sources. This is the first report for the isolation of compounds 1 and 2 from natural sources and the structure determination using NMR experiment. It was also of note that no glycosyl glyceride has previously been isolated from the family of Malvaeae. Most glycosyl glycerides showed cytotoxicity to HepG2, AGS, HCT-15, and A549 human cancer cells. Especially, compounds 1, 2, and 11 exhibited significant cytotoxicity to AGS cells, with IC50 values of 33.7 ±â€¯0.64 µM, 11.1 ±â€¯0.07 µM, and 10.6 ±â€¯0.10 µM, respectively. The n-BuOH fraction and compounds 1, 2, and 11 increased the number of apoptotic cells in the Tali assay and had a significant effect on the levels of proteins related to apoptosis including PARP, caspase-3, Bcl-2, Bax, and ß-actin.

New Lignans from the Flower of Forsythia koreana and Their Suppression Effect on VCAM-1 Expression in MOVAS Cells.

Six lignans including two new lignans were obtained as the principal components of the Forsythia koreana flowers via silica gel (SiO2 ), octadecyl SiO2 (ODS) as well as Sephadex LH-20 column chromatography. In addition to two new lignans, named koreanaside A ((7R,8S,7'R,8'S)-7,7'-diepoxy-5'-hydroxy-3,3'-dimethoxylignan 4-O-ß-d-glucopyranoside) and koreanaside B ((7R,8S,7'S,8'R)-7,9'-epoxy-9,5',7'-trihydroxy-3,3'-dimethoxylignan 4-O-ß-d-glucopyranoside), four known lignans were identified to be (+)-phylligenin, (-)-epipinoresinol, pinoresinol, and tinosposide A. The structures and absolute configurations of koreanasides A and B were established by means of analysis of spectroscopic data (NMR, IR, FAB-MS, and CD), whereas the structures of known lignans were identified by comparison their NMR and MS values with those in the reported literature. Their chemical structures including configuration were established by means of analysis of spectroscopic data (NMR, IR, FAB-MS, and CD) but also comparison of their NMR and MS values with those in the reported literature. This is the first article for isolation of six lignans of F. koreana flowers. Koreanasides A and B showed high radical scavenging activity with oxygen radical absorbance capacity (ORAC) values of 0.97 ± 0.01 and 1.02 ± 0.01, respectively. Koreanaside A also prohibited expressing VCAM-1 in MOVAS cells with 80.5% at 25 mg/mL.

ATP modulates the growth of specific microbial strains.

The regulatory function of extracellular ATP (exATP) in bacteria is unknown, but recent studies have demonstrated exATP induced enhanced secondary metabolite production and morphological differentiation in Streptomyces coelicolor. The growth of Streptomyces coelicolor, however, was unaffected by exATP, although changes in growth are common phenotypes. To identify bacteria whose growth is altered by exATP, we measured exATP-induced population changes in fast-growing microbes and actinomycetes in compost. Compared with the water-treated control, the addition of 10 ml 100 µM ATP to 10 g of compost enhanced the actinomycetes population by 30% and decreased fast-growing microbial numbers by 20%. Eight microbes from each group were selected from the most populated colony, based on appearance. Of the eight isolated fast-growing microbes, the 16S rRNA sequences of three isolates were similar to the plant pathogens Serratia proteamaculans and Sphingomonas melonis, and one was close to a human pathogen, Elizabethkingia meningoseptica. The growth of all fast-growing microbes was inhibited by ATP, which was confirmed in Pseudomonas syringae DC3000, a pathogenic plant bacterium. The growth of six of eight isolated actinomycetes strains, all of which were identified as close to Streptomyces neyagawaensis, was enhanced by ATP treatment. This study suggests that exATP regulates bacterial physiology and that the exATP response system is a target for the control of bacterial ecology.