Antimicrobial activities of different solvent extracts from stem and seeds of Peganum Harmala L.

Wild medicinal herbs have been used as folk and traditional medicines all across the world since well before recorded history. This present study was designed to test the antimicrobial activities of five different solvent extracted samples (n-hexane, n-butanol, ethyl acetate, methanol, and water) of Peganum harmala using stems and seeds. Two different strains of Gram-negative bacteria (Escherichia coli and Klebsiella pneumonia), two Gram-positive bacteria (Bacillus subtilus and Staphylococcus aureus), and one fungal strain (Candida albicans) were used. The antimicrobial activities were measured using a disc diffusion assay. Two concentrations of the extracts (1 and 2mgDisc-1) were used. Ethyl acetate fraction was found more affective among the tested solvents and showed maximum activity (zone of inhibition) against S. aureus (65.53 and 81.10%), E. coli (46.22 and 61.29%) while n-butanol and water fractions gave maximum activity against S. aureus (78.86 and 70.00%) and K. pneumonia (57.00 and 61.39%) respectively. Water fraction showed maximum activity against C. albicans (60.00 and 81.88%). In the case of the stem, Ethyl acetate again showed more activity against B. subtilus (38.57 and 42.10%) and S. aureus (36.66 and 46.66%) while n-butanol showed maximum activity against K. pneumonia (24.55 and 32.44%) and E. coli (27.93 and 37.61%). Methanol was found more effective against C. albicans (25.71 and 43.80%). Seed extracted samples were found more effective compared to the stem. Ethyl acetate, butanol, and aqueous extracted samples showed good activity against the tested microbes, so these fractions are recommended for study their mechanism of actions and isolation of bioactive metabolites responsible for antimicrobial activities. The P. harmala should be evaluated for their bioactive compounds to be used in future studies. Our objective is to provide the framework for future study on the roles of P. harmala as traditional medicines.

Mammillaria Species-Polyphenols Studies and Anti-Cancer, Anti-Oxidant, and Anti-Bacterial Activities.

Discovering new natural resources of polyphenols is the aim of many recent studies in the field of natural product research. This study tentatively investigated the polyphenols profile of the stems of seven Mammillaria species (M. rhodantha, M. spinosissima, M. hahniana, M. crucigera, M. candida, M. albilanata, and M. muehlenpfordtii) using high performance liquid chromatography with DAD detector (HPLC-DAD) method. Furthermore, the anti-cancer, anti-oxidant, and anti-bacterial potentials of these extracts as well as major identified phenols were explored. The HPLC-DAD study confirmed the availability of six phenolic acids, including gentisic acid, chlorogenic acid, caffeic acid, protocatechuic acid, sinapic acid, and p-hydroxybenzoic acid. The dominant compounds were: gentisic acid in M. rhodantha and M. spinosissima; chlorogenic acid in M. muehlenpfordtii, M. crucigera, and M. rhodantha; and caffeic acid in M. rhodantha, M. crucigera, and M. spinosissima. Stems of Mammillaria sp. showed antiproliferative effects against HeLa, MCF-7, and Jurkat cells. In HeLa and MCF-7 cells, the best antiproliferative activities were found in the treatments with M. rhodantha, M. spinosissima, and M. muehlenpfordtii. The apoptotic assay of M. rhodantha, M. spinosissima, and M. muehlenpfordtii showed accumulation of necrotic cells in the early and late apoptotic phase. M. rhodantha, M. spinosissima, and M. muehlenpfordtii showed the highest anti-oxidant activities using 2,2-diphenyl-1-picrylhydrazyl (DPPH), ß-carotene bleaching, and ferric reducing anti-oxidant power (FRAP) assays. M. rhodantha was the best source of antioxidants. Mammillaria sp. showed moderate anti-bacterial effects against bacteria and the highest effects were found using the extracts of M. rhodantha, M. spinosissima, M. crucigera and M. muehlenpfordtii against most bacteria. The anti-bacterial activities were attributed to other phenolic compounds (e.g., chlorogenic acid) than gentisic acid, which was not active against most bacteria. Mammillaria sp. could be considered to be an important natural source of phenolic acids with anti-cancer, anti-bacterial, and anti-oxidant activities.

The first initiative of DNA barcoding of ornamental plants from Egypt and potential applications in horticulture industry.

DNA barcoding relies on short and standardized gene regions to identify species. The agricultural and horticultural applications of barcoding such as for marketplace regulation and copyright protection remain poorly explored. This study examines the effectiveness of the standard plant barcode markers (matK and rbcL) for the identification of plant species in private and public nurseries in northern Egypt. These two markers were sequenced from 225 specimens of 161 species and 62 plant families of horticultural importance. The sequence recovery was similar for rbcL (96.4%) and matK (84%), but the number of specimens assigned correctly to the respective genera and species was lower for rbcL (75% and 29%) than matK (85% and 40%). The combination of rbcL and matK brought the number of correct generic and species assignments to 83.4% and 40%, respectively. Individually, the efficiency of both markers varied among different plant families; for example, all palm specimens (Arecaceae) were correctly assigned to species while only one individual of Asteraceae was correctly assigned to species. Further, barcodes reliably assigned ornamental horticultural and medicinal plants correctly to genus while they showed a lower or no success in assigning these plants to species and cultivars. For future, we recommend the combination of a complementary barcode (e.g. ITS or trnH-psbA) with rbcL + matK to increase the performance of taxa identification. By aiding species identification of horticultural crops and ornamental palms, the analysis of the barcode regions will have large impact on horticultural industry.