Composition of the Fresh Leaves and Stems of <i>Melissa officinalis</i> and Evaluation of Skin Irritation in a Reconstituted Human Epidermis Model

The composition of a centrifuged product obtained from the fresh leaves and stems of Melissa officinalis and skin irritation in the reconstituted human epidermis (Episkin model) have been investigated in comparison to the EtOH−H2O (1:1) extract obtained by Soxhlet from the dried plant. Two new sulfated triterpenes (1 and 2) and two ionol derivatives have been isolated for the first time from Melissa officinalis together with caffeic and rosmarinic acids. The structures of compounds 1 and 2 were established by analysis of their spectroscopic data. Both the centrifuged material and its major constituents neither affected cell viability nor caused the release of pro-inflammatory mediators or the decrease of trans-epithelial electrical resistance (TEER) in the reconstituted human epidermis

Saponins and Polyphenols from <i>Fadogia ancylantha</i> (Makoni Tea)

Three new saponins (1−3) and a known saponin, together with four known polyphenolic compounds, have been isolated from the fermented and dried leaves of Fadogia ancylantha (Makoni tea). The structures of compounds 1−3 were established by analysis of their spectroscopic data. Both an ethanol−water extract of F. ancylantha and its phenolic constituents showed significant free-radical-scavenging and antimicrobial activities. No cytotoxicity, as evaluated by analysis of hypodiploid nuclei in HUVEC cells using propidium iodide staining, was observed for either the plant crude extract or its constituents

Triterpenoid Constituents from the Roots of <i>Paeonia rockii</i> ssp. <i>rockii</i>

An investigation of a chloroform-soluble extract from the roots of Paeonia rockii ssp. rockii yielded three new noroleanane triterpenoids (1–3) together with 19 known compounds. Their structures were established by analysis of the spectroscopic data. The effects of this chloroform-soluble extract and its major constituents on cell proliferation and apoptosis of a panel of human cancer cell lines (melanoma M-14, colon cancer HT-29, breast cancer MCF-7) were evaluated by the MTT bioassay and propidium iodide staining, respectively, in comparison with normal human embryonic kidney cells (HEK-293). Two of the triterpenoids, betulinic acid (4) and oleanolic acid (5), and the crude extract were cytotoxic and induced apoptosis selectively in the M-14 melanoma cell line. This effect was reversed by the caspase-inhibitor z-VAD-fmk, suggesting that such action is mediated by caspase-3 activation

Antioxidant and antiangiogenic activity of <i>Astronium graveolens</i> Jacq. leaves

<div><p>Angiogenesis is involved in many physiological and pathological conditions. Natural compounds with antioxidant activity have also been reported to possess potent antiangiogenic properties by regulating angiogenesis modulators such as vascular endothelial growth factor (VEGF). Based on this, we screened the antioxidant and antiangiogenic activities of <i>Astronium graveolens</i> leaf extracts by a DPPH test and a competitive enzyme-linked immunosorbent assay, respectively. MeOH extract expressed a significant free radical-scavenging activity (EC₅₀ = 37.65 μg/mL) and it was able to inhibit the interaction between placental growth factor (PlGF) (placental growth factor), a VEGF family member, and its receptor Flt-1 by more than 50% at 1 mg/mL. 1,2,3,4,6-Penta-<i>O</i>-galloyl-d-glucopyranose, <b>6</b> is the most active compound of the extract. It exhibited a high potency in scavenging DPPH (EC₅₀ = 2.16 μg/mL) and reduced by 58% the PlGF/Flt-1 interaction at a concentration of 50 μM. Moreover, the known compounds (<b>1</b>–<b>6</b>) have been isolated for the first time in <i>A. graveolens</i>.</p></div

<i>Heliotropium bacciferum</i> Forssk. (Boraginaceae) extracts: chemical constituents, antioxidant activity and cytotoxic effect in human cancer cell lines

<p><i>Heliotropium bacciferum</i> (Boraginaceae) is a perennial herb, growing in the Bechar region of Algeria, where it is traditionally used for skin diseases and tonsillitis. Herein, we report the isolation and characterization of sixteen secondary metabolites from the aerial part extracts. They include a sterol (<b>1</b>), megastigman type nor-isoprenoids (<b>2</b>, <b>3</b>, <b>4</b>, <b>6</b>, <b>8</b>, <b>10</b>), C-11 terpene lactones (<b>5</b> and <b>9</b>), and a monoterpene (<b>7</b>) from the chloroform extract (HB-C); monoterpene glucoside (<b>14</b>), and phenolic compounds (<b>11</b>–<b>13</b>, <b>15</b>, <b>16</b>) from the methanol one (HB-M). Their structures were elucidated by spectroscopic methods including 1D and 2D NMR experiments, and ESIMS analysis. HB-M showed a significant and concentration dependent scavenging activity <i>in vitro</i> against the radicals DPPH and ABTS<i>,</i> related to the phenol derivatives (<b>11</b>–<b>13,</b> and <b>15</b>–<b>16</b>), and HB-C inhibited the growth of colon cancer cell lines, mainly for the presence of the antiproliferative C-11 terpene lactones (<b>5</b> and <b>9</b>).</p

New sesquiterpenes from <i>Asteriscus graveolens</i>

Asteriscus graveolens (Forsk) Less. is a Saharan medicinal plant of Asteraceae family. A new acyclic sesquiterpene [7,12-dihydroxy-6,7-dihydro-5,(6) E-dehydronerolidol (3)] and sesquiterpene germacranolide lactone derivatives [9β-hydroxy-11β,13-dihydroparthenolide-9-O-β-D-glucopyranoside (7) and 9α-hydroxy-11β,13-dihydroparthenolide-9-O-β-D-glucopyranoside (8)] along with eight known compounds were isolated from polar extracts of aerial parts. Their structures were established by the analysis of 1 D- 2 D-NMR and high-resolution mass spectrometry data. A. graveolens extracts and compounds showed a significant (P 50 in a concentration range from 89.4 to 296.0 µg/mL for extracts and from 32.6 to 728.1 µg/mL for compounds. No cytotoxic effects was evidenced in normal Primary Human Dermal Fibroblast (HDFa) up to 0.050 mg/mL for extracts and 1.0 mg/mL for pure compounds.</p

Phytochemical analysis, antioxidant and hypoglycemic activities of a methanol extract from <i>Stachys brachyclada</i> de Noé ex Coss. leaves

Stachys brachyclada de Noé ex Coss. (Lamiaceae) is a quite rare medicinal plant endemic to the Mediterranean basin. In this study, seven secondary metabolites from a methanol extract of its leaves have been isolated and identified by a combination of chromatographic and spectroscopic methods (1D and 2D NMR experiments and ESIMS analysis). They include one ethyl 4-hydroxybenzoate (1), three acylated flavone glycosides (2–4), one diapigenin derivative (5) and two flavone aglycones (6–7). Stachysetin (5) was found the major compound of the extract (74.0 mg/g of dry matter). Moreover, the produced extract showed the ability in inhibiting the α-glucosidase enzyme (IC50 = 13.7 µg/mL), in quenching the radical 1,1-diphenyl-2-picrylhydrazyl (EC50 = 74.6 µg/mL), and in reducing the intracellular oxidative stress level in Human Dermal Fibroblast (64% inhibition at 50 µg/mL).</p

Chemical composition and antioxidant activity of a polar extract of <i>Thymelaea microphylla</i> Coss. et Dur.

<div><p><i>Thymelaea microphylla</i> Coss. et Dur. (Thymelaeaceae) is a rare medicinal plant endemic to Algeria. In order to continue our studies on this species, herein we report the isolation and characterisation of 20 compounds from a hydroalcoholic extract (EtOH–H₂O 7:3) of the aerial parts. They include monoterpene glucosides (<b>1</b>–<b>3</b>), phenolic acid derivatives (<b>4</b>, <b>8</b> and <b>9</b>), phenylpropanoid glucosides (<b>5</b> and <b>6</b>), flavonoids (<b>7</b>, <b>10</b> and <b>11</b>), a benzyl alcohol glucoside (<b>12</b>), ionol glucosides (<b>13</b>–<b>16</b>), lignans (<b>17</b>–<b>19</b>) and a bis-coumarin (<b>20</b>). All the structures were elucidated by spectroscopic methods including 1D and 2D NMR experiments, as well as ESI-MS analysis. Moreover, the extract of <i>T. microphylla</i> showed a significant and concentration-dependent free radical-scavenging activity <i>in vitro</i>, correlated to the presence of phenolic and chlorogenic acid derivatives (<b>8</b>, <b>9</b> and <b>4</b>).</p></div