A. Makboul

Chromones and flavans from Pancratium maritimum.

Abstract A new chromone(5,7-dihydroxy-6-methoxy-2,8-dimethyl) and a new flavan (4-hydroxy-5,7-dimethoxy-8-methyl), together with two known chromones and a flavan were isolated from the bulbs of Pancratium maritimum . The two compounds were characterized by spectral analysis.

A new pentacyclic triterpenoid from the leaves of Lantana montevidensis (Spreng.) Briq.

A new pentacyclic triterpenoid, 3β,25-epoxy-3α,22β,23α-trihydroxy-olean-12-en-28-oic acid (1), together with seven known compounds, including five triterpenoids, β-amyrin (2), lantadene B (3), lantanilic acid (4), lantanolic acid (5) and ursolic acid (6) in addition to β-sitosterol (7) and benzoic acid (8) has been isolated from the leaves of Lantana montevidensis. Their chemical structures were elucidated by spectroscopic analysis and by comparison with the literature data and/or authentic samples. Compound 1 showed moderate to weak antibacterial activity against Staphylococcus aureus and Escherichia coli.

Characterisation of the metabolites of an antibacterial endophyte Botryodiplodia theobromae Pat. of Dracaena draco L. by LC–MS/MS

Botryodiplodia theobromae Pat. belongs to the endophytic fungi that live within the tissues of medicinal plants and produce bioactive natural products. The endophyte was isolated from the leaves of Dracaena draco L. The LC–MS-based metabolite fingerprinting of the ethyl acetate extract of B. theobromae with antibacterial activity led to the identification of 13 metabolites pertaining to various classes: dipeptides (maculosin and L,L-cyclo(leucylprolyl), alkaloid (norharman), coumarin and isocoumarins (bergapten, meranzin and monocerin), sesquiterpene (dihydrocumambrin A), aldehyde (formyl indanone), fatty alcohol (halaminol A) and fatty acid amide (palmitoleamide, palmitamide, capsi-amide and oleamide). This study reports for the first time, the LC–MS and LC–MS/MS identification of 13 known bioactive metabolites from the antibacterial ethyl acetate extract of B.theobromae isolated from the leaves of D. draco L.

Investigation of essential oil and biological activities of Lantana montevidensis (Spreng.) Briq. cultivated in Egypt

Background: Lantana montevidensis (L. montevidensis) is native to Brazil, the tea and infusions of the dried leaves have been used in folk medicine. Previous study of L. montevidensis leaves has resulted in the isolation of ten anti-proliferative fl avones. Also, the essential oil of the Brazilian L. montevidensis leaves was investigated for its chemical composition and antimicrobial activity. Furthermore, the ethanolic extracts of the leaves and roots demonstrated anti-bacterial activity. Materials and Methods: The essential oils extracted by hydrodistillation from the Egyptian L. montevidensis leaves and fl owers were investigated for their chemical composition. Also, a qualitative phytochemical analysis of 70% aqueous methanolic extract of L. montevidensis leaves was performed for the detection of alkaloids, tannins, triterpenoids, steroids, fl avonoids, anthraquinones, saponins, iridoids, carbohydrates and/or glycosides. Furthermore, the extracts from the leaves were assessed for their anti-infl ammatory, anti-pyretic, analgesic, antioxidant and antibacterial activities. Results: The composition of the essential oils included large amount of sesquiterpenes, mainly caryophyllene (33.74%), ß-selinene (43.95%), germacrene-D (3.79%) and nerolidol (6.32%) in the oil of the leaves, while caryophyllene (42.38%), γ-terpinene (22.64%), D-germacrene (9.10 %) and nerolidol (7.09%) are major in the oil of the fl owers. Phytochemical screening of 70% aqueous methanolic extract of L. montevidensis leaves revealed the presence of carbohydrates and/or glycosides, unsaturated sterols, triterpenoids and fl avonoids in addition to traces of saponins and iridoids. Furthermore, the extracts from the leaves exhibited anti-infl ammatory, anti-pyretic, analgesic, antioxidant and antibacterial activities. Conclusion: The obtained results may provide a support to explore the plant for isolation of the active constituents accountable for these activities.

Iridoid and phenylpropanoid glycosides from the roots of Lantana montevidensis

A new iridoid glycoside; 6-O-β-D-xylopyranoside-shanzhiside methyl ester (1) along with six known compounds; shanzhiside methyl ester (2), lamalbid (3), geniposidic acid (4), theveside (5), verbascoside (6) and arenarioside (7) were isolated from the roots of Lantana montevidensis. The structures of the compounds were determined through 1D and 2D NMR spectroscopic data analysis, HRESIMS, electronic circular dichorism and UPLC-UV/MS method. The total extract, chloroformic (F1) and aqueous (F2) fractions together with the isolated compounds were tested for their antimicrobial, antiprotozoal, antiplasmodial, anti-inflammatory, monoamine oxidase inhibition and cell viability activities in addition to free radical scavenging activity using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. The phenylpropanoid compounds (6 and 7) resulted in a potent antioxidant activity. Total methanolic extract together with the aqueous fraction (F2) showed decrease in reactive oxidative stress with 57 and 66%, respectively, while the chloroformic fraction (F1), together with the total methanolic extract, showed a decrease in iNOS with IC50 values 5 and 30 μg/mL, respectively. Compounds 1, 2, 3, 6, and 7 showed inhibition in the reactive oxidative stress with values 50, 60, 57, 63, and 52%, respectively. Both F1 and F2 fractions demonstrated measurable inhibition of MCF-7 breast cancer cell growth, with IC50 value 0.3 mg/mL. Compounds 2 and 7 showed mild monoamine oxidase inhibition. None of the tested compounds showed antimicrobial, antiplasmodial or antiprotozoal activity.

Sesquiterpene lactones from Artemisia argentea

Abstract The aerial parts of Artemisia argentea afforded, in addition to arborescin and argentiolides A and B, one new ketopelenolide derivative named deacetylargentiolide B and some previously unreported guaianolides.

LC-MS metabolite fingerprinting and MtSK-based screening of an endophyte Bartalinia pondoensis Marinc of Citrus aurantum L.

An endophyte Bartalinia pondoensis Marinc of Citrus aurantum L. var. dulcis was isolated and studied for its secondary metabolites and for their Mycobacterium tuberculosis shikimate kinase (MtSK) inhibitory activities. Using LC-MS metabolite fingerprinting of the constituents of the methanol extract, 19 compounds pertaining to various classes were identified: amino acids, proto-alkaloids, fatty acid amides and oxazole, aniline derivatives and aromatic compounds. We report here for the first time the presence of the [N-(ethyloxy, hydroxymethyl)phenylethylamine] as a new proto-alkaloid and 18 other known compounds are reported for the first time in the genus of Bartalinia. MtSK inhibitory activities of methanol extract and fractions obtained by solid phase extraction (SPE) at a concentration of 50 μg/mL may be attributed to the presence of aniline and oxazole derivatives present in all fractions in varying concentrations.