Antineoplastic Agents 540. The Indian Gynandropsis gynandra (Capparidaceae)

Isolation and Identification of Flavones Responsible for the Antibacterial Activities of Tillandsia bergeri Extracts

Plants are an everlasting inspiration source of biologically active compounds. Among these medicinal plants, the biological activity of extracts from some species of the Tillandsia genus has been studied, but the phytochemistry of the hardy species Tillandsia bergeri remains unknown. The aim of the present study was to perform the first phytochemical study of T. bergeri and to identify the compounds responsible for the antibacterial activity of T. bergeri extracts. Soxhlet extraction of predried and grinded leaves was first performed using four increasing polarity solvents. A bio-guided fractionation was performed using agar overlay bioautography as a screening method against 12 Gram-positive, Gram-negative, sensitive, and resistant bacterial strains. The results showed the inhibition of Gram-positive methicillin-sensitive Staphylococcus aureus ATCC 29213 (MSSA), methicillin-resistant S. aureus N-SARM-1 (MRSA), and Staphylococcus caprae ATCC 35538 by the dichloromethane fraction. A phytochemical investigation led to the isolation and identification by high-resolution mass spectrometry and nuclear magnetic resonance of the two flavones penduletin and viscosine, responsible for this antibacterial activity. For viscosine, the minimum inhibitory concentration (MIC) value is equal to 128 μg/mL against MSSA and is equal to 256 μg/mL against MRSA and S. caprae. The combination of these compounds with vancomycin and cloxacillin showed a decrease in MICs of the antibiotics. Penduletin showed synergistic activity when combined with vancomycin against MSSA (FICI < 0.258) and S. caprae (FICI < 0.5). Thus, unexplored Tillandsia species may represent a valuable source for potential antibiotics and adjuvants.

Achillea fragrantissima (Forssk.) Sch.Bip. methanolic extract exerts potent antimicrobial activity and causes cancer cell death via induction of caspase-dependent apoptosis and S-phase arrest

This study was done to evaluate the anticancer potential of Achillea fragrantissima (Forssk.) Sch.Bip. leaves methanolic extract in detail for the first time, in addition to investigating its antimicrobial activity. The antimicrobial assay revealed that the extract exerted high activity against P. vulgaris (MIC = 156.25 µg/ml) and C. albicans (MIC = 625 µg/ml), while moderate activity was observed against other microbes. The extract was also screened against HepG2, A549, HCT116 and MCF7 cancer cells and was found to be active across all cells with highest selectivity and cytotoxic activity being observed for A549 cells (IC₅₀ = 1.21 µg/ml). Further mechanistic studies on A549 cells showed that the extract resulted in S-phase arrest and induced apoptosis via activation of caspase-3, p53 and Bax, in addition to downregulation of Bcl-2. HR-LCMS analysis indicated the presence of 3-hydroxycoumarin, quercetin 3,3'-dimethyl ether and skullcapflavone II which might be responsible for the extract's bioactivity.

Integration of medicinal plants into the traditional system of medicine for the treatment of cancer in Sokoto State, Nigeria

This study was designed to explore and record various medicinal plants integrated into the traditional system of medicine for the treatment of cancer. The traditional system of medicine is a routine practiced among the indigenous ethnic groups of Sokoto state. A semi-structured questionnaire was designed and used for data collection around the selected Local Government Areas. A substantial number of plant species were identified, recorded, and collected for preservation. Data collected for each specie was analysed to assess its frequent use among the medicinal plants. A total of 67 species belonging to 31 families have been identified and recorded. Out of the 473 frequency of citation (FC), Acacia nilotica was the most frequently cited specie (32 FC, 64% FC, 0.6 RFC), followed by Guiera senegalensis (27 FC, 54% FC, 0.5 RFC), Erythrina sigmoidea (17 FC, 34% FC, 0.3 RFC), and subsequently Combretum camporum (15 FC, 30% FC, 0.3 RFC). The most common parts of the plants used include the barks (55.2%), the roots (53.2%), and the leaves (41.8%). Additionally, decoction (74.6%), powdered form (49.3%), and maceration (46.3%) are the most frequently used mode of preparation. The historical knowledge of a traditional system of medicine practiced by the native traditional healers of Sokoto for the treatment of cancer has been documented. The present study further provides a baseline for future pharmacological investigations into the beneficial effects of such medicinal plants for the treatment of cancer.

Chemodiversity Studies on Exudate Flavonoids of Cleomaceae species (Brassicales)

Seven species of the genus Cleome were analysed for formation of exudate flavonoids. The majority of structures found were polymethoxyflavonols with 6- and/or 8- O-substitution. A novel compound, isolated from C. felina, was determined to be 5,3′,4′-triOH-3,6,7,5′-tetraOMe-flavone (1), and a further novel compound, 5,3′-diOH-3,7,8,4′,5′-pentaOMe-flavone (3), was isolated from C. viscosa. Flavones with corresponding substitution have primarily been found in C. droserifolia. Rather simple flavanones such as naringenin-7-Me have so far been found only in one accession of C. hassleriana. The flavonoid profiles of the newly studied species and accessions are discussed in relation to phytochemical, taxonomical and pharmacological data.