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An upsurge in global population due to speedy urbanization and industrialization is facing significant challenges such as rising energy-demand, enormous waste-generation and environmental deterioration. The waste-to-energy nexus based on the 5R principle (Reduce, Reuse, Recycle, Recovery, and Restore) is of paramount importance in solving these Gordian knots. This review essentially concentrates on latest advancements in the field of 'simultaneous waste reduction and energy production' technologies. The waste-to-energy approaches (thermal and biochemical) for energy production from the agricultural residues are comprehensively discussed in terms environmental, techno-economic, and policy analysis. The review will assess the loopholes in order to come up with more sophisticated technologies that are not only eco-friendly and cost-effective, but also socially viable. The waste-to-energy nexus as a paradigm for sustainable development of restoring waste is critically discussed considering future advancement plans and agendas of the policy-makers. Image 1 • Waste-to-energy technologies have been comprehensively reviewed. • Thermal route of waste treatment provides char, oil and syngas as products. • Biochemical treatment of waste yields biogas, ethanol and hydrogen energy. • Using agricultural waste to obtain energy can solve 'crop residue burning' issue. • The environmental and techno-economic analysis was briefly discussed. [ABSTRACT FROM AUTHOR]

The global threat of antimicrobial resistant strains calls for innovative strategies to utilize nano drug delivery systems to enhance the delivery of antibiotics, thus reducing the development of resistance. Supramolecular amphiphiles that can self-assemble into nanostructures are one such nano delivery system, that are showing potential for effective drug delivery. The aim of this study was to synthesize and formulate a novel sugar-based cationic amphiphile (BCD-OLA) derivative from a Beta-cyclodextrin (BCD) head and long C18 carbon chain with a terminal amine; oleylamine (OLA), using inclusion complexation for application in antibiotic delivery. A suspension method was used for preparing the BCD-OLA amphiphile, which was then utilized for the formulation of nanovesicles. The complexation of BCD-OLA was confirmed by FTIR, 1H NMR, 2D NMR NOESY spectrum and molecular dynamic (MD) simulations. Thereafter, biosafety was evaluated using the in vitro MTT cytotoxicity assay. Size, zeta potential (ZP), polydispersity index (PDI), entrapment efficiency, in vitro drug release and antimicrobial activity of BCD-OLA-loaded nanovesicles was also evaluated. MD of the BCD-OLA simulation showed that the mechanism responsible for amphiphile formation was through hydrophobic inclusion of OLA in BCD. MTT results showed cell viability of 75–100%, thus affirming biosafety of BCD-OLA complex. TEM images showed the self-assembled structures to be vesicles. The formulated nanovesicles size was shown to be 125.1 ± 8.30 nm with a PDI of 0.231 ± 0.05, and ZP of 19.3 ± 9.20mv. The encapsulation efficiency of vancomycin was 40.2 ± 4.5%. Vancomycin release from the nanovesicles was found to be sustained, with an 80% release over a 48 h period. The in vitro antibacterial test showed that the BCD-OLA had a 2- and 4-fold lower MIC against Staphylococcus aureus (SA) and Methicillin-resistant Staphylococcus aureus (MRSA), respectively, compared to bare vancomycin. Further, intracellular and macrophage studies showed that the system had a 459-fold reduction of intracellular bacteria using infected human embryotic kidney cells (HEK), and an 8-fold reduction in infected macrophages, contrast with bare vancomycin. These discoveries affirmed the potential of the BCD-OLA complex as a promising biosafe effective nanocarrier for antibiotic delivery. [ABSTRACT FROM AUTHOR]