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This study involves the generation of gold nanoparticles (Au NPs) via a novel natural/non-toxic methodology using tea and orange-peel extracts. These were then embedded into a novel blend composed of a polyethylene oxide and gelatin (PEO-Gel) fibre mat. The scanning electron microscopy results indicated that the addition of both collagen (COL) and ascorbic acid (AA) into the PEO-Gel system (PEO-Gel-AA-COL system) enhances the Au NP incorporation into nanofibres leading to a diameter of 164.60 ± 20.95 and 192.43 ± 39.14 nm in contrast to the spraying observed with the Au PEO-Gel system alone. Releasing studies conducted over 30 min indicated that the PEO-Gel-AA-COL-orange peel Au (OpAu) system accounts for a higher content of Au release than the green tea Au (GtAu) NP system where a maximum release could be attained within 10–30 min depending on the amount of Au NPs that have been incorporated. Moreover, the transdermal diffusion studies conducted using Strat membrane indicated that Au NPs from both formulations (PEO-Gel-AA-COL-GtAu nanofibre, PEO-Gel-AA-COL-OpAu nanofibre) have diffused through the stratum corneum and trapped in the dermis and epidermis indicating its transdermal deliverability. Additionally, 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay revealed that nanofibres have similar radical scavenging activity like AA standard. Toxicity evaluation on a zebra fish embryo model confirmed that both GtAu NPs and OpAu NPs do not induce any teratogenic activity and are safe to be used in the range of 1.0–167 µg ml −1 .

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The transmembrane protein, ARV1, plays a key role in intracellular sterol homeostasis by controlling sterol distribution and cellular uptake. To date, only the ARV1s from yeast and humans have been characterized to some extent. In this study, the ARV1 of an animal filarial parasite, Setaria digitata (SdARV1), was characterized; its cDNA was 761 bp and encoded a protein of 217 amino acids, with a predicted molecular weight of 25 kDa, containing a highly conserved ARV1 homology domain and three transmembrane domains in the bioinformatic analyses. Information required to cluster members belonging to a particular taxon has been revealed in phylogenetic analyses of ARV1 sequences derived from different organisms. Reverse transcription-polymerase chain reaction (RT-PCR) analyses indicated that SdARV1 was expressed in different developmental stages - microfilariae and adult male and female worms. Experiments carried out with a single copy of the SdARV1 under the control of the PMA-1 promoter in a temperature-sensitive Saccharomyces cerevisiae mutant strain indicated full complementation of the mutant phenotype, with growth at a non-permissive temperature (37°C). Microscopic observations of cellular morphology with Gram staining revealed alteration of the shape from shrunken to oval, in mutant and complemented strains, respectively. Assessment of free sterol levels extracted from mutant yeast and complemented strains indicated that the level of sterol was significantly higher in the former compared to the latter, which had sterol levels similar to those of the wild type. Thus, the results of the current study suggest that SdARV1 is ubiquitously expressed in different developmental stages of S. digitata, and that it is a true functional homologue of mammalian and yeast ARV1s, which have crucial phylogenetic information that follows classical evolutionary trends. Finally, this is the first study to report the biological function of nematode ARV1.