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The phytochemical investigation of Caralluma quadrangula aerial parts yielded six new pregnane glycosides, quadrangulosides A–F (1–6), in addition to nine known pregnane glycosides and three known flavone glycosides.

Chemical constituents of Raphanus sativus Linn. roots were extracted and tested for their toxicity against adults and second instar nymphs of A. gossypii under laboratory conditions. The most effective fraction against both adults and nymphs was methylene chloride fraction with LC50 values of 386.63 and 309.43 ppm, followed by ethyl acetate fraction with LC50 values of 394.9 and 334.37 ppm then petroleum ether fraction with LC50 values of 636.2 and 424.56 ppm, for adults and nymphs, respectively. Also, the volatile components of each fraction were qualitatively and quantitatively identified and characterized by GC/MS technique. Moreover, the impact of the sub-lethal concentrations of R. sativus roots extracts on transaminases and alkaline phosphatase of A. gossypii was studied. Great inhibition of all tested enzymes activity was observed. This suggested the high potency of R. sativus roots extracts as environmentally friendly alternatives of traditional insecticides. Chemical constituents of Raphanus sativus Linn. roots were extracted and tested for their toxicity against adults and second instar nymphs of A. gossypii under laboratory conditions. The most effective fraction against both adults and nymphs was methylene chloride fraction with LC50 values of 386.63 and 309.43 ppm, followed by ethyl acetate fraction with LC50 values of 394.9 and 334.37 ppm then petroleum ether fraction with LC50 values of 636.2 and 424.56 ppm, for adults and nymphs, respectively. Also, the volatile components of each fraction were qualitatively and quantitatively identified and characterized by GC/MS technique. Moreover, the impact of the sub-lethal concentrations of R. sativus roots extracts on transaminases and alkaline phosphatase of A. gossypii was studied. Great inhibition of all tested enzymes activity was observed. This suggested the high potency of R. sativus roots extracts as environmentally friendly alternatives of traditional insecticides.

Chemical investigation of the whole Fagonia schimperi C. Presl plant yielded a new triterpene saponin, namely 3-O-β- xylopyranosyl-(1→2)-α-L-arabinopyranosyl-27-hydroxyoleanolic acid 28-O-β-glucopyranoside (1), along with five known natural products 2–6. Structures of the isolated compounds were elucidated by intensive spectroscopic methods including Electrospray Ionisation-Mass Spectrometry (ESI-MS) and 1D and 2D-NMR, which matched the literature data. Fagonia schimperi crude saponin fraction, ethyl acetate (EtOAc) fraction, and the new compound (1) were investigated for their biological activities as antibacterial, antioxidant, and cytotoxicity. EtOAc fraction and compound (1) were the most potent agents, wherein they displayed potent antibacterial activity against both Gram-positive (Staphylococcus aureus and Bacillus subtilis) and Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa). Additionally, the EtOAc fraction displayed potent antiproliferative activity against hepatocellular carcinoma and mammary gland with IC50 values of 7.38 ± 0.4 and 4.89 ± 0.3 μg/ml, respectively. Furthermore, compound 1 showed a significant cytotoxic activity against the two cell lines with IC50 values of 19.20 ± 1.4 and 8.18 ± 0.9, μg/ml, respectively. This comes in agreement with the antioxidant activity that was assessed by 2,2,1-diphenyl-1-picrylhydrazyl and SOD-like activity methods in the following order: EtOAc fraction > compound 1 > crude saponin fraction.

During the screening programme for antibiotic produced by actinomycetes, an antibiotic was isolated from the fermentation broth of Streptomyces anulatus NEAE-94. The ethyl acetate extract of S. anulatus NEAE-94 showed high biological activity against Staphylococcus aureus NRRL B-313, multidrug-resistant S. aureus and Bacillus subtilis NRRL B-543. Thin-layer chromatography of the ethyl acetate extract showed one yellowish orange spot with an Rf value of 0.83. The structural elucidation of the isolated compounds was carried out using ultraviolet–visible mass spectrometry (MS), Fourier transform-infrared spectroscopy (FT-IR), proton nuclear magnetic resonance (1H-NMR) and gas chromatography–mass spectrometry (GC–MS) analyses. Characterization of the ethyl acetate extract revealed the presence of 22 compounds, including an unsaturated fatty acid, saturated fatty acids, fatty acid esters, alkanes, alkenes and a triterpene. The antimicrobial efficacy of S. anulatus NEAE-94 might be due to the synergistic effects of the identified compounds.

Marine natural products (MNPs) continue to be in the spotlight in the global drug discovery endeavor. Currently, more than 30,000 structurally diverse secondary metabolites from marine sources have been isolated, making MNPs a profound, renewable source to investigate novel drug compounds. Marine sponges of the genus Suberea (family: Aplysinellidae) are recognized as producers of bromotyrosine derivatives, which are considered distinct chemotaxonomic markers for the marine sponges belonging to the order Verongida. This class of compounds exhibits structural diversity, ranging from simple monomeric molecules to more complex molecular scaffolds, displaying a myriad of biological and pharmacological potentialities. In this review, a comprehensive literature survey covering the period of 1998⁻2018, focusing on the chemistry and biological/pharmacological activities of marine natural products from marine sponges of the genus Suberea, with special attention to the biogenesis of the different skeletons of halogenated compounds, is presented.

Pyrroloquinoline and guanidine-derived alkaloids present distinct groups of marine secondary metabolites with structural diversity that displayed potentialities in biological research. A considerable number of these molecular architectures had been recorded from marine sponges belonging to different marine genera, including Batzella, Crambe, Monanchora, Clathria, Ptilocaulis and New Caledonian starfishes Fromia monilis and Celerina heffernani. In this review, we aim to comprehensively cover the chemodiversity and the bioactivities landmarks centered around the chemical constituents exclusively isolated from these three marine genera including Batzella, Crambe and Monanchora over the period 1981–2017, paying a special attention to the polycyclic guanidinic compounds and their proposed biomimetic landmarks. It is concluded that these marine sponge genera represent a rich source of novel compounds with potential applications for cancer and other therapeutic areas.

This review presents the phytochemical constituents of the genus Plectranthus reported up to 1999. Only a tetrameric derivative of caffeic acid was isolated from P. japonicus, but a group of long-chain alkylphenols, of possible taxonomic significance in the genus, was also isolated. As a genus of the subfamily Nepetoideae, Plectranthus is free from iridoid glycosides and rich in essential oil (i.e. > 0.5% volatile oil on a dry weight basis). Diterpenoids are the more common secondary metabolites in Plectranthus. The majority of them are highly modified abietanoids. This seems to be similar to the pattern of diterpenoids observed for Salvia, but no clerodane diterpenoids were found in Plectranthus.

Separation of the extract of the tubers of Scirpus holoschoenus L. (familyCyperaceae), a species easily confused with Juncus plants, afforded 2-prenyl-3,5,4'-trimethoxystilbene, 2-prenyl-3-hydroxy-5,4'-dimethoxystilbene, 2-prenyl-3,4'-dihydroxy-5-methoxy-stilbene and 3,5,4'-trimethoxystilbene, in addition to a new acetophenonederivative. The isolated compounds were identified on the basis of spectral measurements. Keywords: Scirpus holoschoenus , Cyperaceae, stilbene, prenylstilbenes, acetophenonederivative. _________________________________________________________________________________________________ _____________ Introduction Scirpus holoschoenus L. (family Cyperaceae) is a rare, salty-marsh, perennial, ca. 1 meter highgrass-like herb. Morphologically, it could be easily confused with Juncus (rush; family Juncaceae)because it is devoid of the characteristic solid three-angled stem of Scirpus [1], having instead a hollowcylindrical stem.From the phytochemical point of view

Balanites aegyptiaca (L.) Delile (Zygophyllaceae) is a tropical tree that has many folk uses in various countries. The bark extract is used for the control of the fresh water snails that act as intermediary host of Schistosoma.Study the molluscicidal activity and chemical constituents of seed oil and seed glycosides of B. aegyptiaca against Monacha cartusiana and determine the structure-activity relationship.Two bioassay methods (residual film application and the leaf dipping technique) were used to evaluate the toxicity effect of the seed oil and glycosides, in concentrations of 1.000, 0.500, 0.250 and 0.125%. The seed oil was analysed by GC/MS. Acid hydrolysis and chromatographic separation were used to study the seed saponins.The bioassay of B. aegyptiaca against the land snail, M. cartusiana, indicated the activity of the seed oil and the high activity of the seed saponins. The seed glycosides gave 30.0, 53.3, 73.0 and 73.3% mortality for concentrations of 0.125, 0.250, 0.500 and 1.00%, respectively. The LC(50) values were 0.335 and 0.256%, respectively. The seed oil was analysed by GC/MS. Acid hydrolysis of the seed saponins gave a mixture of diosgenin, yamogenin and 3,5-spirostadiene.To study the structure-activity relationship, a triterpenoidal saponin and a triterpenoidal saponins rich extract (of Zygophyllum coccenum) were proven to be inactive. Thus, the activity is associated with the steroidal, not triterpenoidal saponins. Moreover, a spirostane aglycone without sugar moiety, was found to be inactive and attained the activity by glycosidation.