Preparation of Terpenoid-Invasomes with Selective Activity against S. aureus and Characterization by Cryo Transmission Electron Microscopy

Kaltschmidt B, Ennen I, Greiner J, et al. Preparation of Terpenoid-Invasomes with Selective Activity against S. aureus and Characterization by Cryo Transmission Electron Microscopy. Biomedicines. 2020;8(5): 105.Terpenoids are natural plant-derived products that are applied to treat a broad range of human diseases, such as airway infections and inflammation. However, pharmaceutical applications of terpenoids against bacterial infection remain challenging due to their poor water solubility. Here, we produce invasomes encapsulating thymol, menthol, camphor and 1,8-cineol, characterize them via cryo transmission electron microscopy and assess their bactericidal properties. While control- and cineol-invasomes are similarly distributed between unilamellar and bilamellar vesicles, a shift towards unilamellar invasomes is observable after encapsulation of thymol, menthol or camphor. Thymol- and camphor-invasomes show a size reduction, whereas menthol-invasomes are enlarged and cineol-invasomes remain unchanged compared to control. While thymol-invasomes lead to the strongest growth inhibition of S. aureus, camphor- or cineol-invasomes mediate cell death and S. aureus growth is not affected by menthol-invasomes. Flow cytometric analysis validate that invasomes comprising thymol are highly bactericidal to S. aureus. Notably, treatment with thymol-invasomes does not affect survival of Gram-negative E. coli. In summary, we successfully produce terpenoid-invasomes and demonstrate that particularly thymol-invasomes show a strong selective activity against Gram-positive bacteria. Our findings provide a promising approach to increase the bioavailability of terpenoid-based drugs and may be directly applicable for treating severe bacterial infections such as methicillin-resistant S. aureus

Desiccation-tolerant fungal blastospores: From production to application

Dietsch R, Jakobs-Schoenwandt D, Grünberger A, Patel A. Desiccation-tolerant fungal blastospores: From production to application. Current Research in Biotechnology. 2021;3:323-339.Increasingly changing climates and ever-growing population sizes paint a worrisome picture of future food scarcity across the globe. Of the potential ways to combat what in many countries is already a problem today, biological pest control is a sustainable approach to ensure crop safety from pest damage. In the biotechnological process from fermentation, to formulation, to desiccation, and finally to storage of the finished biocontrol product, the low desiccation tolerance and shelf life of the biological component is one of the main challenges to overcome. Entomopathogenic fungi, popular and established biocontrol agents, are no exception to this. In many species, a tradeoff between ease of mass production and the shelf life of fungal propagules takes place. Blastospores are easily produced in high quantities, but the desiccation necessary to ensure a sufficient shelf life of blastospore products has a significant impact on blastospore survival. In comparison with other propagule types, blastospores are especially vulnerable to desiccation, so that measures to increase shelf life for successful commercialization must be taken. Fortunately, the multifaceted production process of blastospore biocontrol agents leaves room for vastly different approaches to do so. This review showcases studies from several approaches and puts them into context with the cellular effects of desiccation. The review also evaluates the given literature to facilitate the identification of impactful studies for future blastospore research

Preparation of Terpenoid-Invasomes with Selective Activity against S. aureus and Characterization by Cryo Transmission Electron Microscopy

Terpenoids are natural plant-derived products that are applied to treat a broad range of human diseases, such as airway infections and inflammation. However, pharmaceutical applications of terpenoids against bacterial infection remain challenging due to their poor water solubility. Here, we produce invasomes encapsulating thymol, menthol, camphor and 1,8-cineol, characterize them via cryo transmission electron microscopy and assess their bactericidal properties. While control- and cineol-invasomes are similarly distributed between unilamellar and bilamellar vesicles, a shift towards unilamellar invasomes is observable after encapsulation of thymol, menthol or camphor. Thymol- and camphor-invasomes show a size reduction, whereas menthol-invasomes are enlarged and cineol-invasomes remain unchanged compared to control. While thymol-invasomes lead to the strongest growth inhibition of S. aureus, camphor- or cineol-invasomes mediate cell death and S. aureus growth is not affected by menthol-invasomes. Flow cytometric analysis validate that invasomes comprising thymol are highly bactericidal to S. aureus. Notably, treatment with thymol-invasomes does not affect survival of Gram-negative E. coli. In summary, we successfully produce terpenoid-invasomes and demonstrate that particularly thymol-invasomes show a strong selective activity against Gram-positive bacteria. Our findings provide a promising approach to increase the bioavailability of terpenoid-based drugs and may be directly applicable for treating severe bacterial infections such as methicillin-resistant S. aureus

The Conservation Social Sciences: What?, How? and Why?

to understanding the relationship between humans and nature and to improving conservation outcomes. Conservation scientists, practitioners and organizations recognize the importance of the conservation social sciences and are increasingly engaging in and funding conservation social science research. Yet conservation organizations and funders often lack a clear understanding of the breadth of the conservation social sciences, the types of questions that each field of conservation social science poses, the methods used by disciplinary specialists, or the potential contribution of each field of conservation social science to improving conservation practice and outcomes. Limited social science capacity and knowledge within conservation organizations may also mean that conservation practitioners and organizations looking to fund conservation social science research do not know where or how to begin defining a social science research agenda