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Saponin surfactants extracted from plants have significant potential applications in many industries. The interfacial properties of extracts of Alphitonia excelsa, a native Australian plant rich in saponins, have been characterised to assess their suitability as dual-purpose foaming and antibacterial additives. Two sources of the plant (Adelaide Botanic Gardens and homelands of Chuulangun Aboriginal Corporation) were investigated to look for alteration of properties as a result of differences in cultivation and geographic location. Two methods of saponin extraction (water and water/ethanol mixtures) were investigated to determine differences in extraction efficiency and performance. Distinct differences were observed between the traditional analytical analysis (for saponin content) of the extracts based on source and extraction method; however, these differences were not as stark when considering the effect of the extracts on air–water interfacial tension and dilatational rheology, with extraction method proving to be the single biggest factor in extract efficacy. The data obtained point toward the presence of an altered array of surface-active species (different relative amounts of particular saponins in the water/ethanol extracted material) as a function of the extraction method. All extracts presented some antibacterial effect, albeit modest. This work highlights that the extraction method needs to be carefully considered and tailored for a given application. [ABSTRACT FROM AUTHOR]

Bioactivity-guided fraction of an extract of Sophora flavescens to identify antibacterial compounds against Acinetobacter baumannii, led to the isolation of two new compounds, (2″R)-5-methoxy-7-hydroxy-8-lavandulylchromone (13) and (2S,βS)-(-)-sophobiflavonoid CE (19), and 18 known flavonoids, (6aR,11aR)-(-)-maackiain (1), (2S)-(-)-8-prenylnaringenin (2), (2S)-(-)-exiguaflavanone K (3), (2S)-(-)-sophoraflavanone G (4), (2S)-(-)-leachianone A (5), (2S)-(-)-kushenol E (6), (2S)-(-)-leachianone G (7), (±)-kushenol F (8), (2S)-(-)-kurarinone (9), (2S)-(-)-kurarinol (10), (2 R,3R)- (+)-3,7,4'-trihydroxy-5-methoxy-8-prenylflavanone (11), (2S)-(-)-isoxanthohumol (12), (2S)-(-)-2'-methoxykurarinone (14), (2 R,3R)-(+)-kushenol I (15), calycosin (16), kuraridin (17), (2S)-(-)-kushenol A (18), and trifolirhizin (20). Their structures were elucidated based on NMR, MS, and CD spectroscopic analysis. Among them, 1, 2, 5, and 15 exerted modest antibacterial activity against A. baumannii, with MIC95 of 128-256 μg/mL for 2 and 256-512 μg/mL for 1, 5 and 15. [ABSTRACT FROM AUTHOR]

Acinetobacter baumannii is a pathogen with high intrinsic antimicrobial resistance while multidrug resistant (MDR) and extensively drug resistant (XDR) strains of this pathogen are emerging. Treatment options for infections by these strains are very limited, hence new therapies are urgently needed. The bacterial cell division protein, FtsZ, is a promising drug target for the development of novel antimicrobial agents. We have previously reported limited activity of cinnamaldehyde analogs against Escherichia coli. In this study, we have determined the antimicrobial activity of six cinnamaldehyde analogs for antimicrobial activity against A. baumannii. Microscopic analysis was performed to determine if the compounds inhibit cell division. The ontarget effect of the compounds was assessed by analyzing their effect on polymerization and on the GTPase activity of purified FtsZ from A. baumannii. In silico docking was used to assess the binding of cinnamaldehyde analogs. Finally, in vivo and in vitro safety assays were performed. All six compounds displayed antibacterial activity against the critical priority pathogen A. baumannii, with 4-bromophenyl-substituted 4 displaying the most potent antimicrobial activity (MIC 32 mg/mL). Bioactivity was significantly increased in the presence of an efflux pump inhibitor for A. baumannii ATCC 19606 (up to 32-fold) and significantly, for extensively drug resistant UW 5075 (greater than 4-fold), suggesting that efflux contributes to the intrinsic resistance of A. baumannii against these agents. The compounds inhibited cell division in A. baumannii as observed by the elongated phenotype and targeted the FtsZ protein as seen from the inhibition of polymerization and GTPase activity. In silico docking predicted that the compounds bind in the interdomain cleft adjacent to the H7 core helix. Di-chlorinated 6 was devoid of hemolytic activity and cytotoxicity against mammalian cells in vitro, as well as adverse activity in a Caenorhabditis elegans nematode model in vivo. Together, these findings present halogenated analogs 4 and 6 as promising candidates for further development as antimicrobial agents aimed at combating A. baumannii. This is also the first report of FtsZ-targeting compounds with activity against an XDR A. baumannii strain. [ABSTRACT FROM AUTHOR]

Abstract Background A number of surveys have examined use of complementary and alternative medicines (CAM) in Australia. However, there are limited Australian data on use of CAM and over-the-counter (OTC) medicines in the elderly population. The main aims of this study were to examine self-medication practices with CAM and OTC medicines among older Australians and variables associated with their use. Methods The Australian Longitudinal Study of Ageing (ALSA) is an ongoing multidisciplinary prospective study of the older population which commenced in 1992 in South Australia. Data collected in 4 waves of ALSA between 1992 and 2004 were used in this study with a baseline sample of 2087 adults aged 65 years and over, living in the community or residential aged care. OTC medicines were classified according to the World Health Organization Anatomical Therapeutic Chemical (ATC) classification. CAM were classified according a modified version of the classification adopted by the Therapeutics Goods Administration (TGA) in Australia. Results The prevalence of CAM or OTC use ranged from 17.7% in 2000-2001 to 35.5% in 2003-2004. The top classes of CAM and OTC medicines used remained relatively constant over the study period. The most frequent classes of CAM used were vitamins and minerals, herbal medicines and nutritional supplements while the most commonly used OTC were analgesics, laxatives and low dose aspirin. Females and those of younger age were more likely to be CAM users but no variable was associated with OTC use. Conclusion Participants seemed to self-medicate in accordance with approved indications, suggesting they were informed consumers, actively looking after their own health. However, use of analgesics and aspirin are associated with an increased risk of adverse drug events in the elderly. Future work should examine how self-medication contributes to polypharmacy and increases the risk of adverse drug reactions.

Abstract Background Provision of consumer information and patient education are considered an essential part of chronic disease management programmes developed for patients with heart failure. This study aimed to review the quality and availability of consumer information materials for people with heart failure in Australia. Methods The availability of consumer information was assessed through a questionnaire-based survey of the major organisations in Australia known, or thought, to be producing or using consumer materials on heart failure, including hospitals. The questionnaire was designed to explore issues around the use, production and dissemination of consumer materials. Only groups that had produced consumer information on heart failure were asked to complete the totality of the questionnaire. The quality of information booklets was assessed by using a standardised checklist. Results Of 101 organisations which were sent a questionnaire, 33 had produced 61 consumer resources on heart failure including 21 information booklets, 3 videos, 5 reminder fridge magnets, 7 websites, 15 self-management diaries and 10 self-management plans. Questionnaires were completed for 40 separate information resources. Most had been produced by hospitals or health services. Two information booklets had been translated into other languages. There were major gaps in the availability of these resources as more than half of the resources were developed in 2 of the 8 Australian states and territories, New South Wales and Victoria. Quality assessment of 19 information booklets showed that most had good presentation and language. Overall eight high quality booklets were identified. There were gaps in terms of topics covered, provision of references, quantitative information about treatment outcomes and quality and level of scientific evidence to support medical recommendations. In only one case was there evidence that consumers had been involved in the production of the booklets. Conclusion Key findings arising from the study included the need to develop a nationally coordinated approach for increasing the dissemination of information resources on heart failure. While the more recent publication of a booklet by the National Heart Foundation may have improved the situation, dissemination of written information materials may remain sub-optimal, especially among patients who are not enrolled in chronic heart failure management programmes.