Constituents of Formosan Rhamnus Species Part II. Flavonoids from Rhamnus Formosan Matsum

Three crystalline compounds, rhamnetin(1), rhamnocitrin(4), and kaempferol(6) were isolated from the hot methanol extract of leaves of Rhamnus formosana Matsum.     

Isofuranodiene is the main volatile constituent of Smyrnium perfoliatum L. subsp. perfoliatum growing in central Italy

The essential oil hydrodistilled from the aerial parts of Smyrnium perfoliatum subsp. perfoliatum growing in central Italy was analysed by GC-MS. The main peak in the gas chromatogram was given by the furanosesquiterpene curzerene which is the Cope rearrangement product of isofuranodiene formed into injector and column during the gas chromatographic run. A truthful quantification of these compounds was achieved by HPLC-DAD analysis which showed that isofuranodiene is the main volatile component (180.0 mg/g eo) of S. perfoliatum subsp. perfoliatum, while curzerene occurs in small amounts (18.1 mg/g eo).     

A new glucosidic phthalide from Helichrysum microphyllum subsp. tyrrhenicum from La Maddalena Island (Sardinia,Italy)

In this study, we reported the analysis of the medium polarity fraction obtained from an accession of Helichrysum microphyllum subsp. tyrrhenicum from La Maddalena Island. Besides several compounds already evidenced in this species and related genera, i.e. micropyrone (1), arzanol (2), helipyrone (3), acetyl-bitalin derivatives (4, 5), gnaphaliol (6), caffeic acid (7), ursolic acid (8), 7-O-β-(d-glucopyranosyl)-5-methoxy-1(3H)-isobenzofuranone (9), gnaphaliol-9-O-β-d-glucopyranoside (11) and gnaphaliol-3-O-β-d-glucopyranoside (12), the presence of a new glycosidic phthalide, 6-O-β-(d-glucopyranosyl)-4-methoxy-1(3H)-benzofuranone (10), was evidenced for the first time, which resulted in a structural isomer of compound (9). The occurrence of this new benzofuranone derivative is an additional evidence of the deep intraspecific variability expressed by this species, which was also stated for the non-volatile components, and may be a distinctive trait of the population growing on La Maddalena Island.     

长萼小连翘醇提物中黄酮类与金丝桃素类成分的HPLC/DAD-MS联用分析

利用HPLC/DAD-ESI(-)MS联用技术对植物长萼小连翘(Hypericum erectum subsp.longisepalum L.H.Wu et D.P.Yang)中主要化学成分进行了分离分析,初步鉴定出金丝桃素、伪金丝桃素、原伪金丝桃素、绿原酸、芦丁、金丝桃苷、槲皮素等12种黄酮类、酚酸类和金丝桃素类等化学成分.     

Inhibitory Effect of LGS and ODE Isolated from the Twigs of Syringa oblata subsp. dilatata on RANKL-Induced Osteoclastogenesis in Macrophage Cells

Osteoblasts and osteoclasts play a pivotal role in maintaining bone homeostasis, of which excessive bone resorption by osteoclasts can cause osteoporosis and various bone diseases. However, current osteoporosis treatments have many side effects, and research on new treatments that can replace these treatments is ongoing. Therefore, in this study, the roles of ligustroside (LGS) and oleoside dimethylester (ODE), a natural product-derived compound isolated from Syringa oblata subsp. dilatata as a novel, natural product-derived osteoporosis treatments were investigated. In the results of this study, LGS and ODE inhibited the differentiation of receptor activator of nuclear factor kappa-Β ligand (RANKL)-induced RAW264.7 cells into osteoclasts without cytotoxicity, and down-regulated the activity of TRAP, a specific biomarker of osteoclasts. In addition, it inhibited bone resorption and actin ring formation, which are important functions and features of osteoclasts. Also, the effects of LGS and ODE on the mitogen-activated protein kinase (MAPK) and nuclear factor kappa-light-chain-enhancer of activated B (NF-κB) and phosphoinositide 3-kinases (PI3K)/ protein kinase B (Akt)/mechanistic target of rapamycin (mTOR) signaling pathways that play important roles in osteoclast differentiation were evaluated. In the results, LGS and ODE downregulated the phosphorylation of RANKL-induced MAPK and PI3K/Akt/mTOR proteins in a concentration-dependent manner, translocation of NF-κB into the nucleus was inhibited. As a result, the compounds LGS and ODE isolated from S. oblate subsp. dilatata effectively regulated the differentiation of RANKL-induced osteoclasts and inhibited the phosphorylation of signaling pathways that play a pivotal role in osteoclast differentiation. Therefore, these results suggest the possibility of LGS and ODE as new natural product treatments for bone diseases caused by excessive osteoclasts.     

Essential oil composition of aerial parts from Algerian Anacyclus monanthos subsp. cyrtolepidioides (Pomel) Humphries

The chemical composition of the essential oil from the aerial parts of Anacyclus monanthos subsp. cyrtolepidioides (Pomel) Humphries (Asteraceae) growing in a semi-arid region of Algeria was investigated for the first time. The essential oil was obtained by hydrodistillation and fully characterized by gas chromatography-mass spectrometry (GC-MS). A total of 97 compounds were identified. The essential oil was found to be rich in trans-chrysanthenyl acetate (9.8 ± 2.0%), (E)-β-farnesene (7.4 ± 1.5%), germacrene D (6.9 ± 1.3%) and myristicin (4.8 ± 0.8%).     

Essential oil composition and biological activity from Artemisia caerulescens subsp. densiflora (Viv.) Gamisans ex Kerguélen & Lambinon (Asteraceae), an endemic species in the habitat of La Maddalena Archipelago

The purpose of this study was to investigate the composition of the essential oil obtained from a population of Artemisia caerulescens subsp. densiflora growing in Razzoli, an island in the La Maddalena Archipelago (Sardinia, Italy). A. caerulescens sups. densiflora Viv. (Asteraceae), a wild herb, seldom studied in the Mediterranean, represents one of the many rare endemic species growing in North Sardinia. The essential oil composition was analysed by means of GC/MS analysis, which showed davana ethers as the major volatile components, accounting together for 17.5%, followed by (E)-nerolidol (4.5%), β-oplopenone (3.3%), cis-sabinene hydrate (5.2%) and terpinen-4-ol (4.7%). The oil was tested for antioxidant activity by means of DPPH test, inhibition of lipid oxidation test and hypochlorous acid test, which showed a quite interesting scavenger capacity. For the first time, we reported the cytotoxic activity of the essential oil of A. caerulescens subsp. densiflora, against three human tumour cell lines (A375, MDA-MB231 and HCT116), with IC₅₀ values in the range 5.20–7.61 μg/mL, which deserved further studies to support its use as chemopreventive agent. Finally, the antimicrobial activity of the essential oil, displayed on a panel of human pathogens, was very low.     

Bioguided Isolation of Active Compounds from Rhamnus alaternus against Methicillin-Resistant Staphylococcus aureus (MRSA) and Panton-Valentine Leucocidin Positive Strains (MSSA-PVL)

Despite intensified efforts to develop an effective antibiotic, S. aureus is still a major cause of mortality and morbidity worldwide. The multidrug resistance of bacteria has considerably increased the difficulties of scientific research and the concomitant emergence of resistance is to be expected. In this study we have investigated the in vitro activity of 15 ethanol extracts prepared from Moroccan medicinal plants traditionally used for treatment of skin infections. Among the tested species I. viscosa, C. oxyacantha, R. tinctorum, A. herba alba, and B. hispanica showed moderate anti-staphylococcal activity. However, R. alaternus showed promising growth-inhibitory effects against specific pathogenic bacteria especially methicillin-susceptible Staphylococcus aureus Panton-Valentine leucocidin positive (MSSA-PVL) and methicillin-resistant S. aureus (MRSA). The bioguided fractionation of this plant using successive chromatographic separations followed by nuclear magnetic resonance (NMR) and mass spectrometry (MS) including EIMS and HREIMS analysis yielded the emodin (1) and kaempferol (2). Emodin being the most active with MICs ranging between 15.62 and 1.95 µg/mL and showing higher activity against the tested strains in comparison with the crude extract, its mechanism of action and the structure-activity relationship were interestingly discussed. The active compound has not displayed toxicity toward murine macrophage cells. The results obtained in the current study support the traditional uses of R. alaternus and suggest that this species could be a good source for the development of new anti-staphylococcal agents.     

Chemical composition of the essential oil of Jacobaea maritima (L.) Pelser & Meijden and Jacobaea maritima subsp. bicolor (Willd.) B. Nord. & Greuter (Asteraceae) collected wild in Croatia and Sicily,respectively

In this study, the chemical compositions of the essential oils from aerial parts (JmA) and radices (JmR) of Jacobaea maritima (L.) Pelser & Meijden, collected in Croatia, and of Jacobaea maritima subsp. bicolor (Willd.) B. Nord. & Greuter, collected in Sicily, were evaluated by using gas chromatography and gas chromatography–mass spectrometry. The main components of the essential oil from J. maritima, both in JmA and JmR, were pentacosane (15.7%), heptacosane (13.1%) and nonacosane (8.1%) whereas the essential oil from J. maritima subsp. bicolor was characterised by the presence of hexadecanoic acid (14.6%), caryophyllene oxide (9.3%) and hexahydrofarnesylacetone (6.5%). The comparison of the essential oil with other studied oils of the genus Jacobaea is discussed.     

New Biological and Chemical Evidences of Two Lamiaceae Species (Thymbra capitata and Thymus sipyleus subsp. rosulans): In Vitro,In Silico and Ex Vivo Approaches

In this study, the methanolic and infusion extracts of two species, Thymbra capitata and Thymus sipyleus subsp. rosulans, were tested for their chemical composition and biological abilities (antioxidant, enzyme inhibitory and anti-inflammatory effects). The extracts yielded total phenolic and flavonoid contents in the range of 83.43–127.52 mg GAE/g and 9.41–46.34 mg RE/g, respectively. HPLC analysis revealed rosmarinic acid to be a major component of the studied extracts (15.85–26.43%). The best ABTS radical scavenging ability was observed in the methanol extract of T. capitata with 379.11 mg TE/g, followed by in the methanol extract of T. sipylus (360.93 mg TE/g). In the CUPRAC assay, the highest reducing ability was also found in the methanol extract of T. capitata with 802.22 mg TE/g. The phosphomolybdenum ability ranged from 2.39 to 3.61 mmol TE/g. In terms of tyrosinase inhibitory effects, the tested methanol extracts (83.18–89.66 mg KAE/g) were higher than the tested water extracts (18.74–19.11 mg KAE/g). Regarding the BChE inhibitory effects, the methanol extracts were active on the enzyme while the water extracts showed no inhibitory effect on it. Overall, the methanolic extracts showed better enzyme inhibition compared to the infusion extracts. Molecular docking also showed the selected exhibited potential binding affinities with all enzymes, with a preference for cholinesterases. Additionally, the extracts were effective in attenuating the LPS-induced increase in COX-2 and IL-6 gene expression in isolated colon, thus indicating promising anti-inflammatory effects. The preliminary results of this study suggest that these species are good natural sources of antioxidants and also provide some scope as enzyme inhibitors, most likely due to their bioactive contents such as phenolic acids, and thus can be exploited for different applications related to health promotion and disease prevention.