In vitro antibacterial and cytotoxic activity of leaf extracts of Centella asiatica (L.) Urb, Warburgia salutaris (Bertol. F.) Chiov and Curtisia dentata (Burm. F.) C.A.Sm - medicinal plants used in South Africa

Abstract Background Compounds having both anticancer and antimicrobial activity have promising therapeutic potential due to their selective cytotoxicity and their potential to reduce the occurrence of bacterial and fungal infections in immune-compromised cancer patients. In our quest to find new antimicrobial agents with potent anticancer activity, the biological potential of leaves from the three medicinal plants Centella asiatica, Warburgia salutaris and Curtisia dentata as used by Zulu traditional healers for the treatment of cancer is investigated. Methods Extracts were assayed for antibacterial activity using the agar well diffusion and micro plate dilution assay. In addition, minimum bactericidal concentrations (MBC), lactate dehydrogenase (LDH) release assay and rhodamine 6G intake assay were used to ascertain the antibacterial activity. The cytotoxic effects of the plant extracts were determined using tetrazolium-based colorimetric (MTT) cell proliferation assay against MCF-7, human colorectal carcinoma cells (Caco-2), A549 and HeLa cancerous cell lines. Results The acetone extracts from Waburgia salutaris revealed noteworthy anti-proliferative effect yielding IC50 value of 34.15 μg/ml against MCF-7 cell line, while acetone extract from Curtisia dentata significantly (P ≤ 0.05) revealed promising IC50 values of 41.55, 45.13, 57.35 and 43.24 μg/ml against A549, HeLa, CaCo-2 and MCF-7 cell lines. The extracts further revealed a broad-spectrum antibacterial activity against bacterial strains used in the study. An acetone extract from W. salutaris revealed the highest zone of inhibition and the lowest minimum inhibitory concentration (MIC) of 21.0 mm and 0.16 mg/ml respectively against Staphylococcus aureus. Methanol extract from W. salutaris and ethyl acetate extract from C. dentata revealed 53% inhibition of R6G inside the cell against Staphylococcus aureus and Escherichia coli respectively in a cytosolic lactate dehydrogenase assay, suggesting that the mode of action of such extracts may be through efflux pump. Conclusions Overall, the extracts had good antibacterial activity and anti-proliferative effects against selected cancerous cell lines. Given the good antibacterial activity of the extracts the plants may act as an immune booster and prevent infection in immunosuppressed cancer patients. This is further supported by the plants’ anti-proliferative potential, bacteriostatic, bactericidal properties and also their ability to block bacterial efflux pump systems

Public attitudes, co-production and polycentric governance in energy policy

Highlights • Large-scale survey and comprehensive sampling of all social groups in two regions of Austria. • Results showing attitudes towards renewable energies. • Results showing level of awareness. • Results on willingness to engage into energy policy. • Recommendations on polycentric governance in energy policy

Co-creating Policies on Societal Transformations as a Factor of Resilience of Modern Society

The goals of climate change mitigation or energy security policies might lead to societal transformations due to large-scale deployment of new technologies or changes in relations about generation, distribution and transmission of electricity. The goals are frequently developed at the national governance levels; however, their implementation takes place at the local governance level. The process of energy transition gives crucial importance to the participation of local communities and their positive attitudes. Such a process should include measures for active engagement of inhabitants and local government while providing a chance to participate in decision-making processes that affect the lives of these people. Currently, participatory governance of energy transition takes place mainly within the discussion about details of the projects and criteria for selection of possible alternatives. It does not include discussion about the need for energy transition or preferences for technologies for decarbonization of the electricity sector. This study investigated social factors linked to the transition of the Austrian energy sector towards a higher share of renewable energy sources. The empirical data show factors which influence the level of awareness about climate change mitigation and energy transition as well as differences in patterns of support for renewable energy sources from various social groups

Mental health literacy of school-going adolescents in sub-Saharan Africa: a regional systematic review protocol

Introduction Assessing mental health literacy has implications for the identification and treatment of mental health problems. Adolescents have been identified as a particularly important target group for initiating and improving mental health literacy. However, much of what we know about adolescent mental health literacy comes from high-income countries. This proposed review seeks to synthesise the available published primary evidence from sub-Saharan Africa on the status and measurement of mental health literacy among school-going adolescents. Methods and analysis We will perform a systematic review reported in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement (PRISMA-2020). We will systematically search selected global databases (EMBASE, PsycINFO, PubMed and MEDLINE) and regional electronic databases (African Index Medicus and African Journals OnLine) up to December 2021 for observational and qualitative studies published in English and French. The standard quality assessment criteria for evaluating primary research papers from a variety of fields (QualSyst criteria) will be used to appraise the methodological quality of the included studies. The Petticrew-Roberts 3-step approach to narrative synthesis will be applied to the included studies. Ethics and dissemination We will not seek ethical approval from an institutional review board, as this is a systematic review of available and accessible literature. When completed, the full report of this review will be submitted to a journal for peer-reviewed publication; the key findings will be presented at local and international conferences with—partial or full—focus on (adolescent) mental health (literacy). PROSPERO registration number CRD42021229011

Heterometallic half-sandwich complexes containing a ferrocenyl motif: Synthesis, molecular structure, electrochemistry and antiplasmodial evaluation

The synthesis and characterisation of a series of new half-sandwich ruthenium(II), rhodium(III) and iridium(III) heterometallic complexes containing a ferrocenyl motif is reported. The dinuclear complexes were prepared by reaction of the ferrocenyl–salicylaldimine complex (1) with either [Ru(p-cymene)Cl2]2, [Rh(C5Me5)Cl2]2 or [Ir(C5Me5)Cl2]2 to yield heterobimetallic complexes where complex 1 acts as a bidentate anionic donor to ruthenium, rhodium or iridium via the imine nitrogen and phenolic oxygen atoms. The structures of the compounds have been confirmed using a variety of spectroscopic and analytical techniques, including single crystal X-ray diffraction analysis of complexes 2–4. The electrochemical behaviour of the heterometallic complexes was examined using cyclic voltammetry and a positive shift in the half-wave potential (E1/2) of the ferrocene/ferrocenium couple was observed for the Platinum Group Metal (PGM) complexes, indicating that the ferrocenyl moiety becomes harder to oxidise. The complexes were evaluated for antiplasmodial activity in vitro against the chloroquine-sensitive Plasmodium falciparum strain NF54, yielding IC50 values in the low micromolar range. Further analysis of complexes 1–4 using a β-hematin inhibition assay revealed that these complexes are able to inhibit the formation of synthetic hemozoin